Investigating intermolecular forces associated with thrombus initiation using optical tweezers
NASA Astrophysics Data System (ADS)
Arya, Maneesh; Lopez, Jose A.; Romo, Gabriel M.; Dong, Jing-Fei; McIntire, Larry V.; Moake, Joel L.; Anvari, Bahman
2002-05-01
Thrombus formation occurs when a platelet membrane receptor, glycoprotein (GP) Ib-IX-V complex, binds to its ligand, von Willebrand factor (vWf), in the subendothelium or plasma. To determine which GP Ib-IX-V amino acid sequences are critical for bond formation, we have used optical tweezers to measure forces involved in the binding of vWf to GP Ib-IX-V variants. Inasmuch as GP Ib(alpha) subunit is the primary component in human GP Ib-IX-V complex that binds to vWf, and that canine GP Ib(alpha) , on the other hand, does not bind to human vWf, we progressively replaced human GP Ib(alpha) amino acid sequences with canine GP Ib(alpha) sequences to determine the sequences essential for vWf/GP Ib(alpha) binding. After measuring the adhesive forces between optically trapped, vWf-coated beads and GP Ib(alpha) variants expressed on mammalian cells, we determined that leucine- rich repeat 2 of GP Ib(alpha) was necessary for vWf/GP Ib-IX- V bond formation. We also found that deletion of the N- terminal flanking sequence and leucine-rich repeat 1 reduced adhesion strength to vWf but did not abolish binding. While divalent cations are known to influence binding of vWf, addition of 1mM CaCl2 had no effect on measured vWf/GP Ib(alpha) bond strengths.
Cosemans, Judith M. E. M.; Schols, Saskia E. M.; Stefanini, Lucia; de Witt, Susanne; Feijge, Marion A. H.; Hamulyák, Karly; Deckmyn, Hans; Bergmeier, Wolfgang
2011-01-01
A microscopic method was developed to study the role of platelets in fibrin formation. Perfusion of adhered platelets with plasma under coagulating conditions at a low shear rate (250−1) resulted in the assembly of a star-like fibrin network at the platelet surface. The focal fibrin formation on platelets was preceded by rises in cytosolic Ca2+, morphologic changes, and phosphatidylserine exposure. Fibrin formation was slightly affected by αIIbβ3 blockage, but it was greatly delayed and reduced by the following: inhibition of thrombin or platelet activation; interference in the binding of von Willebrand factor (VWF) to glycoprotein Ib/V/IX (GpIb-V-IX); plasma or blood from patients with type 1 von Willebrand disease; and plasma from mice deficient in VWF or the extracellular domain of GpIbα. In this process, the GpIb-binding A1 domain of VWF was similarly effective as full-length VWF. Prestimulation of platelets enhanced the formation of fibrin, which was abrogated by blockage of phosphatidylserine. Together, these results show that, in the presence of thrombin and low shear flow, VWF-induced activation of GpIb-V-IX triggers platelet procoagulant activity and anchorage of a star-like fibrin network. This process can be relevant in hemostasis and the manifestation of von Willebrand disease. PMID:21037087
Platelet Glycoprotein Ib-IX and Malignancy
2010-09-01
provide a unique microenvironment supporting the accumulation of more platelets and the elaboration of a fibrin - rich network produced by coagulation...process and can initiate the formation of a platelet - rich thrombus by tethering the platelet to a thrombogenic surface. Several ligands binding to GP Ib... Platelet Glycoprotein Ib-IX and Malignancy PRINCIPAL INVESTIGATOR: Jerry Ware, Ph.D
Dong, Jing-fei; Moake, Joel L; Nolasco, Leticia; Bernardo, Aubrey; Arceneaux, Wendy; Shrimpton, Corie N; Schade, Alicia J; McIntire, Larry V; Fujikawa, Kazuo; López, José A
2002-12-01
Thrombotic thrombocytopenic purpura (TTP) is a devastating thrombotic disorder caused by widespread microvascular thrombi composed of platelets and von Willebrand factor (VWF). The disorder is associated with a deficiency of the VWF-cleaving metalloprotease, ADAMTS-13, with consequent accumulation of ultralarge (UL) VWF multimers in the plasma. ULVWF multimers, unlike plasma forms of VWF, attach spontaneously to platelet GP Ibalpha, a component of the GP Ib-IX-V complex. We have found that ULVWF multimers secreted from stimulated endothelial cells (ECs) remained anchored to the endothelial surface where platelets and Chinese hamster ovary cells expressing the GP Ib-IX-V complex attached to form long beads-on-a-string structures in the presence of fluid shear stresses in both the venous (2.5 dyne/cm(2)) and arterial (20 and 50 dyne/cm(2)) ranges. Although measurement of the activity of the ADAMTS-13 VWF-cleaving metalloprotease in vitro requires prolonged incubation of the enzyme with VWF under nonphysiologic conditions, EC-derived ULVWF strings with attached platelets were cleaved within seconds to minutes in the presence of normal plasma (containing approximately 100% ADAMTS-13 activity) or in the presence of partially purified ADAMTS-13. By contrast, the strings persisted for the entire period of perfusion (10 minutes) in the presence of plasma from patients with TTP containing 0% to 10% ADAMTS-13 activity. These results suggest that cleavage of EC-derived ULVWF multimers by ADAMTS-13 is a rapid physiologic process that occurs on endothelial cell surfaces.
Platelet Glycoprotein lb-1X and Malignancy
2010-09-01
supporting the accumulation of more platelets and the elaboration of a fibrin - rich network produced by coagulation factors. This paradigm has been...a platelet - rich thrombus by tethering the platelet to a thrombogenic surface. Several ligands binding to GP Ib-IX have been identified, including...08-1-0576 TITLE: Platelet Glycoprotein lb-1X and Malignancy PRINCIPAL INVESTIGATOR: Dr. Jerry Ware
Dimerization of glycoprotein Ibα is not sufficient to induce platelet clearance.
Liang, X; Syed, A K; Russell, S R; Ware, J; Li, R
2016-02-01
ESSENTIALS: Many anti-glycoprotein (GP)Ibα antibodies induce platelet clearance in a dimer-dependent manner. Characterization of monoclonal antibodies that bind the mechanosensitive domain (MSD) of GPIbα. An anti-MSD antibody binds two copies of GPIbα in platelets but does not induce platelet clearance. The prevailing clustering model of GPIbα signaling is incorrect or needs revision. The mechanism of platelet clearance is not clear. Many antibodies binding the membrane-distal ligand-binding domain of glycoprotein (GP)Ibα induce rapid clearance of platelets and acute thrombocytopenia, which requires the bifurcated antibody structure. It was thought that binding of these antibodies induced lateral dimerization or clustering of GPIbα in the plasma membrane, which leads to downstream signaling and platelet clearance. However, many antibodies targeting GPIbβ and GPIX, which are associated with GPIbα in the GPIb-IX complex, do not induce platelet clearance, which is in contradiction to the clustering model. To test whether dimerization or clustering of GPIbα is sufficient to transmit the signal that leads to platelet clearance. We have recently raised several mAbs targeting the mechanosensitive domain (MSD) of GPIbα. Binding of these anti-MSD antibodies was characterized with biochemical methods. Their ability to stimulate platelets and induce platelet clearance in mice was assessed. Infusion of anti-MSD antibodies does not cause thrombocytopenia in mice. These antibodies show no detectable effects on platelet activation and aggregation in vitro. Further biochemical investigation showed that the anti-MSD antibody 3D1 binds two copies of GPIbα on the platelet surface. Therefore, lateral dimerization of GPIbα induced by antibody binding is not sufficient to initiate GPIb-IX signaling and induce platelet clearance. Our results suggest that a factor other than or in addition to clustering of GPIbα is required to induce platelet clearance. © 2015 International Society on Thrombosis and Haemostasis.
Interlandi, Gianluca; Yakovenko, Olga; Tu, An-Yue; Harris, Jeff; Le, Jennie; Chen, Junmei; López, José A; Thomas, Wendy E
2017-11-10
The plasma protein von Willebrand factor (VWF) is essential for hemostasis initiation at sites of vascular injury. The platelet-binding A1 domain of VWF is connected to the VWF N-terminally located D'D3 domain through a relatively unstructured amino acid sequence, called here the N-terminal linker. This region has previously been shown to inhibit the binding of VWF to the platelet surface receptor glycoprotein Ibα (GpIbα). However, the molecular mechanism underlying the inhibitory function of the N-terminal linker has not been elucidated. Here, we show that an aspartate at position 1261 is the most critical residue of the N-terminal linker for inhibiting binding of the VWF A1 domain to GpIbα on platelets in blood flow. Through a combination of molecular dynamics simulations, mutagenesis, and A1-GpIbα binding experiments, we identified a network of salt bridges between Asp 1261 and the rest of A1 that lock the N-terminal linker in place such that it reduces binding to GpIbα. Mutations aimed at disrupting any of these salt bridges activated binding unless the mutated residue also formed a salt bridge with GpIbα, in which case the mutations inhibited the binding. These results show that interactions between charged amino acid residues are important both to directly stabilize the A1-GpIbα complex and to indirectly destabilize the complex through the N-terminal linker. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.
Of von Willebrand factor and platelets.
Bryckaert, Marijke; Rosa, Jean-Philippe; Denis, Cécile V; Lenting, Peter J
2015-01-01
Hemostasis and pathological thrombus formation are dynamic processes that require multiple adhesive receptor-ligand interactions, with blood platelets at the heart of such events. Many studies have contributed to shed light on the importance of von Willebrand factor (VWF) interaction with its platelet receptors, glycoprotein (GP) Ib-IX-V and αIIbβ3 integrin, in promoting primary platelet adhesion and aggregation following vessel injury. This review will recapitulate our current knowledge on the subject from the rheological aspect to the spatio-temporal development of thrombus formation. We will also discuss the signaling events generated by VWF/GPIb-IX-V interaction, leading to platelet activation. Additionally, we will review the growing body of evidence gathered from the recent development of pathological mouse models suggesting that VWF binding to GPIb-IX-V is a promising target in arterial and venous pathological thrombosis. Finally, the pathological aspects of VWF and its impact on platelets will be addressed.
Qiao, Jianlin; Shen, Yang; Shi, Meimei; Lu, Yanrong; Cheng, Jingqiu; Chen, Younan
2014-05-01
Through binding to von Willebrand factor (VWF), platelet glycoprotein (GP) Ibα, the major ligand-binding subunit of the GPIb-IX-V complex, initiates platelet adhesion and aggregation in response to exposed VWF or elevated fluid-shear stress. There is little data regarding non-human primate platelet GPIbα. This study cloned and characterized rhesus monkey (Macaca Mullatta) platelet GPIbα. DNAMAN software was used for sequence analysis and alignment. N/O-glycosylation sites and 3-D structure modelling were predicted by online OGPET v1.0, NetOGlyc 1.0 Server and SWISS-MODEL, respectively. Platelet function was evaluated by ADP- or ristocetin-induced platelet aggregation. Rhesus monkey GPIbα contains 2,268 nucleotides with an open reading frame encoding 755 amino acids. Rhesus monkey GPIbα nucleotide and protein sequences share 93.27% and 89.20% homology respectively, with human. Sequences encoding the leucine-rich repeats of rhesus monkey GPIbα share strong similarity with human, whereas PEST sequences and N/O-glycosylated residues vary. The GPIbα-binding residues for thrombin, filamin A and 14-3-3ζ are highly conserved between rhesus monkey and human. Platelet function analysis revealed monkey and human platelets respond similarly to ADP, but rhesus monkey platelets failed to respond to low doses of ristocetin where human platelets achieved 76% aggregation. However, monkey platelets aggregated in response to higher ristocetin doses. Monkey GPIbα shares strong homology with human GPIbα, however there are some differences in rhesus monkey platelet activation through GPIbα engagement, which need to be considered when using rhesus monkey platelet to investigate platelet GPIbα function. Copyright © 2014 Elsevier Ltd. All rights reserved.
Diem, Vu Thi Kieu; Tyas, Martin J; Ngo, Hien C; Phuong, Lam Hoai; Khanh, Ngo Dong
2014-04-01
The main aim of the study was to compare the clinical performance of the conventional high-powder/liquid ratio glass-ionomer cement (GIC) Fuji IX GP Extra (F IX), Fuji IX GP Extra with a low-viscosity nano-filled resin coating, G-Coat Plus (F IX+GCP), and a resin composite, Solare (S), as a comparison material. Moderate-depth occlusal cavities in the first permanent molars of 91 11-12-year-old children (1-4 restorations per child) were restored with either F IX (87 restorations), F IX+GCP (84 restorations) or S (83 restorations). Direct clinical assessment, photographic assessment and assessment of stone casts of the restorations were carried out at 6 months, 1 year, 2 years and 3 years. The colour match with the tooth of the GIC restorations improved over the 3 years of the study. Marginal staining and marginal adaptation were minimal for all restorations; three restorations exhibited secondary caries at 3 years. From the assessment of the casts, at 2 years, there was significantly less wear of the F IX GP Extra+GCP restorations than the F IX GP Extra restorations (P < 0.005). At 3 years, approximately 37 % of F IX GP Extra restorations showed wear slightly more than the adjacent enamel, compared to 28 % of F IX GP Extra+GCP restorations and 21 % of Solare restorations. Although this was not statistically significant, there was a trend that GCP can protect F IX GP Extra against wear. Although both Fuji IX GP Extra and Fuji IX GP Extra with G-Coat Plus showed acceptable clinical performance in occlusal cavities in children, the application of G-Coat Plus gave some protection against wear. The application of G-Coat Plus to Fuji IX GP Extra glass-ionomer cement may be beneficial in reducing wear in occlusal cavities.
Marchese, Patrizia; Saldívar, Enrique; Ware, Jerry; Ruggeri, Zaverio M.
1999-01-01
We have examined the interaction between the amino-terminal domain of platelet glycoprotein (GP) Ibα and immobilized von Willebrand Factor (vWF) under flow conditions in the absence of other components of the GP Ib–IX–V complex. Latex beads were coated with a recombinant fragment containing GP Ibα residues 1–302, either with normal sequence or with the single G233V substitution that causes enhanced affinity for plasma vWF in platelet-type pseudo-von-Willebrand disease. Beads coated with native fragment adhered to vWF in a manner comparable to platelets, showing surface translocation that reflected the transient nature of the bonds formed. Thus, the GP Ibα extracellular domain is necessary and sufficient for interacting with vWF under high shear stress. Beads coated with the mutated fragment became tethered to vWF in greater number and had lower velocity of translocation than beads coated with the normal counterpart, suggesting that the G233V mutation lowers the rate of bond dissociation. Our findings define an approach for studying the biomechanical properties of the GP Ibα–vWF bond and suggest that this interaction is tightly regulated to allow rapid binding at sites of vascular injury, while permitting the concurrent presence of receptor and ligand in the circulation. PMID:10393908
Platelet interactions in thrombosis.
Andrews, Robert K; Gardiner, Elizabeth E; Shen, Yang; Berndt, Michael C
2004-01-01
Patho/physiological platelet aggregate (thrombus) formation is initiated by engagement of platelet surface receptors, glycoprotein (GP)Ib-IX-V and GPVI that bind von Willebrand factor or collagen. Although beneficial in response to vascular injury by preventing blood loss (haemostasis), platelet aggregation in a sclerotic coronary artery or other diseased blood vessel (thrombosis) can cause thrombotic diseases like heart attack and stroke. At the molecular level, ligand interactions with GPIb-IX-V or GPVI trigger signalling responses, including elevation of cytosolic Ca2+, dissociation of calmodulin from their cytoplasmic domains, cytoskeletal actin-filament rearrangements, activation of src-family kinases or PI 3-kinase, and 'inside-out' activation of the integrin, alphaIIbbeta3 (GPIIb-llla), that binds von Willebrand factor or fibrinogen and mediates platelet aggregation. Furthermore, emerging evidence supports a topographical co-association of these receptors of the leucine-rich repeat family (GPIb-IX-V) and immunoglobulin superfamily (GPVI) in an adhesive cluster or 'adhesosome'. This arrangement may underlie common mechanisms of initiating thrombus formation in haemostasis or thrombotic disease.
Wang, Xiaoshuang; Yang, Liu; Yang, Li; Xing, Faping; Yang, Hua; Qin, Liyue; Lan, Yunyi; Wu, Hui; Zhang, Beibei; Shi, Hailian; Lu, Cheng; Huang, Fei; Wu, Xiaojun; Wang, Zhengtao
2017-12-01
Gypenoside IX (GP IX) is a pure compound isolated from Panax notoginseng. Gypenosides have been implicated to benefit the recovery of enormous neurological disorders. By suppressing the activation of astrocytes, gypenosides can improve the cognitive impairment. However, so far, little is known about whether GP IX could restrain the inflammatory responses in astrocytes or reactive astrogliosis. In present study, the anti-inflammatory effects of GP IX were investigated in reactive astrocytes induced by proinflammatory mediators both in vitro and in vivo. GP IX significantly reduced the production of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) at either protein or mRNA level in glial cell line C6 cells stimulated by lipopolysaccharide (LPS)/TNF-α combination. It also alleviated the astrogliosis and decreased the production of inflammatory mediators in brain cortex of LPS-treated mice. Further study disclosed that GP IX inhibited nuclear translocation of nuclear factor kappa B (NFκB) and reduced its transcriptional activity. Meanwhile, GP IX significantly attenuated the phosphorylation of NFκB, inhibitor of kappa B (IκB), Akt, and p38 mitogen-activated protein kinase (MAPK) under inflammatory conditions both in vitro and in vivo. These findings indicated that GP IX might suppress reactive astrogliosis by suppressing Akt/p38 MAPK/NFκB signaling pathways. And GP IX might be a promising drug candidate or prodrug for the therapy of neuroinflammatory disorders characterized with reactive astrogliosis.
Sanchez, Eladio Flores; Richardson, Michael; Gremski, Luiza Helena; Veiga, Silvio Sanches; Yarleque, Armando; Niland, Stephan; Lima, Augusto Martins; Estevao-Costa, Maria Inácia; Eble, Johannes Andreas
2016-01-01
Initial association of platelets after vascular injury is mediated by glycoprotein (GP)Ib-IX-V binding to von Willebrand factor (vWf) immobilized on exposed collagens and eventually leads to thrombus formation. This article provides data about a new P-I class snake venom metalloproteinase (SVMP), barnettlysin-I (Bar-I), purified from the venom of Bothrops barnetti. This Data in Brief manuscript complements the main research article by providing additional data of the biochemical characterization of Bar-I 10.1016/j.bbagen.2015.12.021[1]. PMID:27222863
DOE Office of Scientific and Technical Information (OSTI.GOV)
Budarf, M.L.; Michaud, D.; Emanuel, B.
Unmasking an autosomal recessive disorder by constitutional hemizygosity is well documented for the embryonal tumors RB and WAGR, where the second hit is a somatic event. Few deletion-mediated recessive conditions have been reported in patients with germline mutations. The major platelet receptor for von Willebrand factor, Glycoprotein Ib (GpIb), is a complex of two plasma membrane glycoproteins, Ib{alpha} and Ib{beta}, covalently linked by disulfide bonds. Defects in this receptor have been associated with the rare congenital autosomal recessive bleeding disorder, Bernard-Soulier syndrome (BSS). BSS is characterized by prolonged bleeding times, thrombocytopenia and very large platelets. The GpIb{beta} gene has beenmore » cloned and we have mapped it within the DGCR. We have identified a patient with phenotypic features of both BSS and VCFS. The patient was referred for 22q11-deletion FISH studies because of a conventricular VSD and mild dysmorphia. FISH with the N25 DiGeorge cosmid demonstrated a deletion in 22q11.2. Western blot analysis of the patient`s platelet proteins demonstrates a complete absence of GpIb{beta}. We suggest that haploinsufficiency for the DGCR in this patient unmasks a mutation in the remaining GpIb{beta} allele, resulting in manifestations of BSS. This mechanism, haploinsufficiency coupled with a mutation of the {open_quotes}normal{close_quotes} chromosome, might explain some of the phenotypic variability seen amongst patients with 22q11.2 microdeletions. These results further suggest that patients with contiguous gene deletion syndromes are at increased risk for autosomal recessive disorders and that they provide the opportunity to {open_quotes}map{close_quotes}disease loci.« less
Sivaraman, Balakrishnan; Latour, Robert A
2011-08-01
Platelet adhesion to adsorbed plasma proteins, such as fibrinogen (Fg), has been conventionally thought to be mediated by the GPIIb/IIIa receptor binding to Arg-Gly-Asp (RGD)-like motifs in the adsorbed protein. In previous studies, we showed that platelet adhesion response to adsorbed Fg and Alb was strongly influenced by the degree of adsorption-induced protein unfolding and that platelet adhesion was only partially blocked by soluble RGD, with RGD-blocked platelets adhering without activation. Based on these results, we hypothesized that in addition to the RGD-specific GPIIb/IIIa receptor, which mediates both adhesion and activation, a non-RGD-specific receptor set likely also plays a role in platelet adhesion (but not activation) to both Fg and albumin (Alb). To identify and elucidate the role of these receptors, in addition to GPIIb/IIIa, we also examined the GPIb-IX-V receptor complex, which has been shown to mediate platelet adhesion (but not activation) in studies by other groups. The platelet suspension was pretreated with either a GPIIb/IIIa-antagonist drug Aggrastat(®) or monoclonal antibodies 6B4 or 24G10 against GPIb-IX-V prior to adhesion on Fg- and Alb-coated OH- and CH(3)-functionalized alkanethiol self-assembled monolayer surfaces. The results revealed that GPIIb/IIIa is the primary receptor set involved in platelet adhesion to adsorbed Fg and Alb irrespective of their degree of adsorption-induced unfolding, while the GPIb-IX-V receptor complex plays an insignificant role. Overall, these studies provide novel insights into the molecular-level mechanisms mediating platelet interactions with adsorbed plasma proteins, thereby assisting the biomaterials field develop potent strategies for inhibiting platelet-protein interactions in the design of more hemocompatible cardiovascular biomaterials and effective anti-thrombotic therapies. Copyright © 2011 Elsevier Ltd. All rights reserved.
Epitope Capsid-Incorporation: New Effective Approach for Vaccine Development for Chagas Disease
Matthews, Qiana L.; Farrow, Anitra L.; Rachakonda, Girish; Gu, Linlin; Nde, Pius; Krendelchtchikov, Alexandre; Pratap, Siddharth; Sakhare, Shruti S.; Sabbaj, Steffanie; Lima, Maria F.; Villalta, Fernando
2016-01-01
Background Previously we reported that a hexon-modified adenovirus (Ad) vector containing the invasive neutralizing epitope of Trypanosoma cruzi (T. cruzi) trypomastigote gp83 (Ad5-gp83) provided immunoprotection against T. cruzi infection. The purpose of this work was to design an improved vaccine for T. cruzi using a novel epitope capsid incorporation strategy. Thus, we evaluated the immunoprotection raised by co-immunization with Ad5-gp83 and an Ad vector containing an epitope (ASP-M) of the T. cruzi amastigote surface protein 2. Methods Protein IX (pIX)-modified Ad vector (Ad5-pIX-ASP-M) was generated, characterized, and validated. C3H/He mice were immunized with Ad5-pIX-ASP-M and Ad5-gp83 and the cell-mediated responses were evaluated by enzyme-linked immunospot (ELISPOT) assay and intracellular staining. Immunized mice were challenged with T. cruzi to evaluate the vaccine efficacy. Results Our findings indicate that Ad5-pIX-ASP-M was viable. Specific CD8+ T-cell mediated responses prior to the challenge show an increase in IFNγ and TNFα production. A single immunization with Ad5-pIX-ASP-M provided protection from T. cruzi infection, but co-immunizations with Ad5-pIX-ASP-M and Ad5-gp83 provided a higher immunoprotection and increased survival rate of mice. Conclusions Overall, these results suggest that the combination of gp83 and ASP-M specific epitopes onto the capsid-incorporated adenoviruses would provide superior protection against Chagas disease as compared with Ad5-gp83 alone. PMID:27709126
De Marco, L; Mazzucato, M; Masotti, A; Ruggeri, Z M
1994-03-04
Glycoprotein (GP) Ib alpha is required for expression of the highest affinity alpha-thrombin-binding site on platelets, possibly contributing to platelet activation through a pathway involving cleavage of a specific receptor. This function may be important for the initiation of hemostasis and may also play a role in the development of pathological vascular occlusion. We have now identified a discrete sequence in the extracytoplasmic domain of GP Ib alpha, including residues 271-284 of the mature protein, which appears to be part of the high affinity alpha-thrombin-binding site. Synthetic peptidyl mimetics of this sequence inhibit alpha-thrombin binding to GP Ib as well as platelet activation and aggregation induced by subnanomolar concentrations of the agonist; they also inhibit alpha-thrombin binding to purified glycocalicin, the isolated extracytoplasmic portion of GP Ib alpha. The inhibitory peptides interfere with the clotting of fibrinogen by alpha-thrombin but not with the amidolytic activity of the enzyme on a small synthetic substrate, a finding compatible with the concept that the identified GP Ib alpha sequence interacts with the anion-binding exosite of alpha-thrombin but not with its active proteolytic site. The crucial structural elements of this sequence necessary for thrombin binding appear to be a cluster of negatively charged residues as well as three tyrosine residues that, in the native protein, may be sulfated. GP Ib alpha has no significant overall sequence homology with the thrombin inhibitor, hirudin, nor with the specific thrombin receptor on platelets; all three molecules, however, possess a distinct region rich in negatively charged residues that appear to be involved in thrombin binding. This may represent a case of convergent evolution of unrelated proteins for high affinity interaction with the same ligand.
Tiefenbacher, S; Bohra, R; Amiral, J; Bowyer, A; Kitchen, S; Lochu, A; Rosén, S; Ezban, M
2017-10-01
Essentials Nonacog beta pegol (N9-GP) is an extended half-life, recombinant human factor IX (FIX). One-stage clotting (OSC) and chromogenic FIX activity assays were assessed for N9-GP recovery. OSC STA ® -Cephascreen ® , ROX FIX and BIOPHEN FIX chromogenic assays were qualified for N9-GP. Other extended half-life factor products should be assessed in a similar way prior to approval. Background Nonacog beta pegol (N9-GP) is an extended half-life, glycoPEGylated recombinant human factor IX that is under development for the prophylaxis and treatment of bleeding episodes in hemophilia B patients. Considerable reagent-dependent variability has been observed when one-stage clotting assays are used to measure the recovery of recombinant FIX products, including N9-GP. Objective To qualify select one-stage clotting and chromogenic FIX activity assays for measuring N9-GP recovery. Methods The accuracy and precision of the one-stage clotting assay (with the STA-Cephascreen activated partial thromboplastin [APTT] reagent) and the ROX Factor IX and BIOPHEN Factor IX chromogenic assays for measuring N9-GP recovery were assessed in N9-GP-spiked hemophilia B plasma samples in a systematic manner at three independent sites, with manufacturer-recommended protocols and/or site-specific assay setups, including different instruments. Results For each of the three FIX activity assays qualified on five different reagent-instrument systems, acceptable intra-assay and interassay accuracy and precision, dilution integrity, reagent robustness and freeze-thaw and short-term sample stabilities were demonstrated. The STA-Cephascreen assay showed a limited reportable range at one of the three qualification sites, and the BIOPHEN Factor IX assay showed suspect low-end sensitivity at one of the three qualification sites. An individual laboratory would account for these limitations by adjusting the assay's reportable range; thus, these findings are not considered to impact the respective assay qualifications. Conclusion The one-stage clotting assay with the STA-Cephascreen APTT reagent, the ROX Factor IX chromogenic assay and the BIOPHEN Factor IX chromogenic assay are considered to be qualified for the measurement of N9-GP in 3.2% (0.109 m) citrated human plasma. © 2017 International Society on Thrombosis and Haemostasis.
Madabhushi, Sri R.; Zhang, Changjie; Kelkar, Anju; Dayananda, Kannayakanahalli M.; Neelamegham, Sriram
2014-01-01
Background Von Willebrand Factor (VWF) A1‐domain binding to platelet receptor GpIbα is an important fluid‐shear dependent interaction that regulates both soluble VWF binding to platelets, and platelet tethering onto immobilized VWF. We evaluated the roles of different structural elements at the N‐terminus of the A1‐domain in regulating shear dependent platelet binding. Specifically, the focus was on the VWF D′D3‐domain, A1‐domain N‐terminal flanking peptide (NFP), and O‐glycans on this peptide. Methods and Results Full‐length dimeric VWF (ΔPro‐VWF), dimeric VWF lacking the D′D3 domain (ΔD′D3‐VWF), and ΔD′D3‐VWF variants lacking either the NFP (ΔD′D3NFP─‐VWF) or just O‐glycans on this peptide (ΔD′D3OG─‐VWF) were expressed. Monomeric VWF‐A1 and D′D3‐A1 were also produced. In ELISA, the apparent dissociation constant (KD) of soluble ΔPro‐VWF binding to immobilized GpIbα (KD≈100 nmol/L) was 50‐ to 100‐fold higher than other proteins lacking the D′D3 domain (KD~0.7 to 2.5 nmol/L). Additionally, in surface plasmon resonance studies, the on‐rate of D′D3‐A1 binding to immobilized GpIbα (kon=1.8±0.4×104 (mol/L)−1·s−1; KD=1.7 μmol/L) was reduced compared with the single VWF‐A1 domain (kon=5.1±0.4×104 (mol/L)−1·s−1; KD=1.2 μmol/L). Thus, VWF‐D′D3 primarily controls soluble VWF binding to GpIbα. In contrast, upon VWF immobilization, all molecular features regulated A1‐GpIbα binding. Here, in ELISA, the number of apparent A1‐domain sites available for binding GpIbα on ΔPro‐VWF was ≈50% that of the ΔD′D3‐VWF variants. In microfluidics based platelet adhesion measurements on immobilized VWF and thrombus formation assays on collagen, human platelet recruitment varied as ΔPro‐VWF<ΔD′D3‐VWF<ΔD′D3NFP─‐VWF<ΔD′D3OG─‐VWF. Conclusions Whereas VWF‐D′D3 is the major regulator of soluble VWF binding to platelet GpIbα, both the D′D3‐domain and N‐terminal peptide regulate platelet translocation and thrombus formation. PMID:25341886
Rekha, C Vishnu; Varma, Balagopal; Jayanthi
2012-07-01
The purpose of this study was to evaluate and compare the tensile bond strength and microleakage of Fuji IX GP, Fuji II LC, and compoglass and to compare bond strength with degree of microleakage exhibited by the same materials. Occlusal surfaces of 96 noncarious primary teeth were ground perpendicular to long axis of the tooth. Preparations were distributed into three groups consisting of Fuji IX GP, Fuji II LC and Compoglass. Specimens were tested for tensile bond strength by mounting them on Instron Universal Testing Machine. Ninety-six primary molars were treated with Fuji IX GP, Fuji II LC, and compoglass on box-only prepared proximal surface. Samples were thermocycled, stained with dye, sectioned, and scored for microleakage under stereomicroscope. ANOVA and Bonferrani correction test were done for comparisons. Pearson Chi-square test and regression analysis were done to assess the association between the parameters. Compoglass showed highest tensile strength and Fuji II LC showed least microleakage. There was a significant difference between the three groups in tensile strength and microleakage levels. The correlation between tensile strength and microleakage level in each group showed that there was a significant negative correlation only in Group 3. Fuji II LC and compoglass can be advocated in primary teeth because of their superior physical properties when compared with Fuji IX GP.
Martinowitz, U; Shapiro, A; Quon, D V; Escobar, M; Kempton, C; Collins, P W; Chowdary, P; Makris, M; Mannucci, P M; Morfini, M; Valentino, L A; Gomperts, E; Lee, M
2012-11-01
IB1001 trenacog alfa is an investigational recombinant factor IX (FIX) for the treatment and prevention of bleeding in individuals with haemophilia B. To compare the pharmacokinetics (PK) of IB1001 with nonacog alfa in individuals with haemophilia B and to assess the relationship between sialylation and PK of IB1001 (NCT00768287). A randomized, double-blind, non-inferiority, cross-over study conducted in participants aged ≥ 12 years weighing ≥ 40 kg, with severe or moderately severe haemophilia B (FIX activity ≤ 2 IU dL (-1) ). PK parameters were derived using observed FIX concentration levels and actual PK sampling times, and repeated in a subset of participants who had received IB1001 prophylaxis for 4-18 months. A retrospective analysis was conducted in subgroups according to the sialylation levels of IB1001 (50.8, 57.8-59.0%, or 71.7%). In the 32 adolescent and adult males evaluated, there were no clinically meaningful differences in PK parameters between those receiving IB1001 75 IU kg(-1) or nonacog alfa. The lower limit of the one-sided 95% confidence interval for the ratio of AUC(0-t) and AUC(0-∞) (IB1001/nonacog alfa) was 0.90, establishing non-inferiority. Terminal phase half-lives were similar (29.7 ± 18.2 h for IB1001 and 33.4 ± 21.2 h for nonacog alfa). The PK results were stable for up to 18 months of IB1001 exposure; the impact of sialylation levels was not clinically meaningful. There were no clinically meaningful PK differences between IB1001 and nonacog alfa. IB1001 was well tolerated and without safety concerns. The non-inferiority of IB1001 to nonacog alfa supports IB1001 becoming a useful alternative recombinant agent for the management of haemophilia B. © 2012 Blackwell Publishing Ltd.
Collins, P W; Quon, D V K; Makris, M; Chowdary, P; Kempton, C L; Apte, S J; Ramanan, M V; Hay, C R M; Drobic, B; Hua, Y; Babinchak, T J; Gomperts, E D
2018-01-01
Trenonacog alfa (IB1001) is a recombinant factor IX (rFIX) manufactured in Chinese hamster ovary (CHO) cells. IB1001 was evaluated in a multicentre clinical trial with haemophilia B patients. The aim was to establish IB1001 pharmacokinetic non-inferiority to comparator rFIX, safety and efficacy in previously treated patients (PTPs) with haemophilia B. Subjects were severe or moderately severe haemophilia B adult and adolescent PTPs with no history of FIX inhibitors. IB1001 PK non-inferiority to comparator rFIX was demonstrated through ratio of AUC 0-∞ in 32 subjects. IB1001 was well tolerated in all 76 treated subjects; the most common adverse drug reaction was headache (2.6% of subjects) and there were no reports of FIX inhibitors. Transient non-inhibitory binding FIX antibodies and anti-CHO cell protein antibodies developed in 21% and 29% of subjects respectively; no safety concerns were associated with development of these antibodies. Prophylaxis (mean duration ± SD: 17.9 ± 9.6 months, mean dose: 55.5 ± 12.9 IU/kg, median 1.0 infusion per week) was effective in preventing bleeds (median annual bleed rate: 1.52, interquartile range: 0.0-3.46). One or two IB1001 infusions resolved 84% of the bleeds, while for 84% of treatments haemostatic efficacy of IB1001 was rated excellent or good. IB1001 haemostatic efficacy for all 19 major surgeries was rated adequate or better than adequate. IB1001 is safe and efficacious for treatment of bleeds, routine prophylaxis and perioperative management in haemophilia B patients. © 2017 The Authors. Haemophilia Published by John Wiley & Sons Ltd.
Honparkhe, M; Singh, Jagir; Dadarwal, D; Dhaliwal, G S; Kumar, Ajeet
2008-12-01
A total of 130 animals (82 cattle, 48 buffaloes) with histories of anestrous 60-90 days post-partum and belonging to different agroclimatic zones of Punjab were subjected to rectal palpation and blood samplings at least three times at weekly intervals. The body condition score (BCS) of each animal was also recorded. The animals were divided into two groups; viz., true anestrous (Gp-I) and subestrus (Gp-II) through rectal palpation of ovaries and plasma progesterone (P4) concentrations. Furthermore, the Gp I and II animals were divided into treatment (Gp Ia, 40 cattle and 16 buffaloes; Gp IIa, 12 cattle and 14 buffaloes) and control groups (Gp Ib, 20 cattle and 8 buffaloes; Gp IIb, 10 cattle and 10 buffaloes). True anestrous animals (Gp Ia) were treated with 3 injections of hydroxyprogesterone caproate (750 mg, i.m.) at 72-hr intervals followed by injection of equine chorionic gonadotropin (eCG; 750 I.U., i.m.) 72 hr after the last progesterone injection. The animals were bred at the first estrus after the induced one. The first service conception rate (FSCR), overall conception rate (OCR), services per conception and pregnancy rate of the true anestrous treated cattle (Gp Ia) were 44.4%, 48.0%, 2.08 and 60.0%, respectively. In the true anestrous control cattle (Gp Ib), only five that were observed to be in estrus failed to conceive. In the anestrous treated buffaloes (Gp Ia), the FSCR, OCR, services per conception and pregnancy rate were 50.0%, 62.5%, 1.6 and 62.5%, respectively. No buffalo amongst true anestrous control (Gp Ib) showed estrus. The subestrus animals (Gp IIa) were administered Prostaglandin F(2alpha) (PGF(2alpha); 25 mg Dinoprost, i.m.) and bred at induced estrus. Amongst the Gp IIa animals, all cattle (100%) and twelve buffaloes (85.7%) responded to treatment. Of these animals, the FSCR and pregnancy rate at induced estrus in the cattle were 50.0% each, whereas they were 66.6% and 57.1%, respectively, in the buffaloes. The subestrus control animals (Gp IIb) remained infertile. In summary, the plasma P(4) profile can be used to differentiate true anestrous and subestrus animals and thus to determine a hormonal therapy. Furthermore, fertile estrus can be induced with hormonal therapy in anestrous and subestrus bovines.
Suva, Larry J.; Hartman, Eric; Dilley, Joshua D.; Russell, Susan; Akel, Nisreen S.; Skinner, Robert A.; Hogue, William R.; Budde, Ulrich; Varughese, Kottayil I.; Kanaji, Taisuke; Ware, Jerry
2008-01-01
The platelet glycoprotein Ib-IX receptor binds surface-bound von Willebrand factor and supports platelet adhesion to damaged vascular surfaces. A limited number of mutations within the glycoprotein Ib-IX complex have been described that permit a structurally altered receptor to interact with soluble von Willebrand factor, and this is the molecular basis of platelet-type von Willebrand disease. We have developed and characterized a mouse model of platelet-type von Willebrand disease (G233V) and have confirmed a platelet phenotype mimicking the human disorder. The mice have a dramatic increase in splenic megakaryocytes and splenomegaly. Recent studies have demonstrated that hematopoetic cells can influence the differentiation of osteogenic cells. Thus, we examined the skeletal phenotype of mice expressing the G233V variant complex. At 6 months of age, G233V mice exhibit a high bone mass phenotype with an approximate doubling of trabecular bone volume in both the tibia and femur. Serum measures of bone resorption were significantly decreased in G233V animals. With decreased bone resorption, cortical thickness was increased, medullary area decreased, and consequently, the mechanical strength of the femur was significantly increased. Using ex vivo bone marrow cultures, osteoclast-specific staining in the G233V mutant marrow was diminished, whereas osteoblastogenesis was unaffected. These studies provide new insights into the relationship between the regulation of megakaryocytopoiesis and bone mass. PMID:18187573
Jeenduang, Nutjaree; Sangkaew, Boonnisa; Chantaracha, Pacharee; Chanchareonsri, Sirada; Plyduang, Thunyaluk; Thitdee, Wanida; Samae, Cathaleeya; Pitumanon, Wacharaporn
2017-03-01
Hibiscus sabdariffa L. (HS) and Gynostemma pentaphyllum Makino (GP) have been used as traditional medicines to treat diabetes and hypercholesterolemia. Nevertheless, there is interindividual variation in the metabolic responses to HS and GP consumption. This may be due to genetic factors. The aim of this study was to investigate the effects of HS and GP tea consumption on anthropometric data, fasting blood glucose (FBG), and lipid concentrations in hypercholesterolemia subjects with different genotypes of the APOE and CETP TaqIB polymorphisms. Forty-eight subjects with hypercholesterolemia were given either HS or GP tea for 30 days. Anthropometric and biochemical variables were determined, and APOE and CETP TaqIB polymorphisms were analyzed using the polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP). E4 (p=0.008) and homozygous B1B1 (p=0.010) carriers had significantly decreased HDL-C concentrations after HS consumption; in addition, B2 carriers who consumed HS showed significantly decreased triglyceride (TG) concentrations (p=0.039). Regarding GP consumption, non-E4 carriers had significantly decreased HDL-C (p=0.009) and FBG (p=0.042) concentrations. Furthermore, B2 carriers had significantly decreased total cholesterol (TC) (p=0.045), HDL-C (p=0.004), and FBG (p=0.026) concentrations. HS consumption may have beneficial effects with respect to TG concentrations in the B2 carriers, but it may adversely affect HDL-C concentrations in homozygous B1B1 and E4 carriers. In contrast, GP consumption may have favorable effects on TC and FBG concentrations but not on HDL-C concentrations for B2 and/or non-E4 carriers.
Bowyer, A E; Hillarp, A; Ezban, M; Persson, P; Kitchen, S
2016-07-01
Essentials Validated assays are required to precisely measure factor IX (FIX) activity in FIX products. N9-GP and two other FIX products were assessed in various coagulation assay systems at two sites. Large variations in FIX activity measurements were observed for N9-GP using some assays. One-stage and chromogenic assays accurately measuring FIX activity for N9-GP were identified. Background Measurement of factor IX activity (FIX:C) with activated partial thromboplastin time-based one-stage clotting assays is associated with a large degree of interlaboratory variation in samples containing glycoPEGylated recombinant FIX (rFIX), i.e. nonacog beta pegol (N9-GP). Validation and qualification of specific assays and conditions are necessary for the accurate assessment of FIX:C in samples containing N9-GP. Objectives To assess the accuracy of various one-stage clotting and chromogenic assays for measuring FIX:C in samples containing N9-GP as compared with samples containing rFIX or plasma-derived FIX (pdFIX) across two laboratory sites. Methods FIX:C, in severe hemophilia B plasma spiked with a range of concentrations (from very low, i.e. 0.03 IU mL(-1) , to high, i.e. 0.90 IU mL(-1) ) of N9-GP, rFIX (BeneFIX), and pdFIX (Mononine), was determined at two laboratory sites with 10 commercially available one-stage clotting assays and two chromogenic FIX:C assays. Assays were performed with a plasma calibrator and different analyzers. Results A high degree of variation in FIX:C measurement was observed for one-stage clotting assays for N9-GP as compared with rFIX or pdFIX. Acceptable N9-GP recovery was observed in the low-concentration to high-concentration samples tested with one-stage clotting assays using SynthAFax or DG Synth, or with chromogenic FIX:C assays. Similar patterns of FIX:C measurement were observed at both laboratory sites, with minor differences probably being attributable to the use of different analyzers. Conclusions These results suggest that, of the reagents tested, FIX:C in N9-GP-containing plasma samples can be most accurately measured with one-stage clotting assays using SynthAFax or DG Synth, or with chromogenic FIX:C assays. © 2016 International Society on Thrombosis and Haemostasis.
Flik, Carla E; Laan, Wijnand; Smout, André J P M; Weusten, Bas L A M; de Wit, Niek J
2015-11-26
Irritable Bowel Syndrome (IBS) is a functional somatic syndrome characterized by patterns of persistent bodily complaints for which a thorough diagnostic workup does not reveal adequate explanatory structural pathology. Detailed insight into disease-specific health-care costs is critical because it co-determines the societal impact of the disease, enables the assessment of cost-effectiveness of existing and new treatments, and facilitates choices in treatment policy. In the present study the aim was, to compare the costs and magnitude of healthcare consumption for patients diagnosed with Irritable Bowel Syndrome (IBS) in primary and secondary care, compare these costs with the average health care expenditure for patients without IBS and describe these costs in further detail. Reimbursement data for patients diagnosed with IBS by a general practitioner (GP) or specialist between 2006 and 2009 were extracted from a healthcare insurance company and compared to an age and gender matched control group of patients without IBS. Using a case-control design, direct medical costs for GP consultations, specialist care and medication prescriptions were calculated. Data of 326 primary care and 9274 secondary care IBS patients were included in the analysis. For primary care patients, the mean total annual health care costs for the three years after diagnosis compared to the three years before diagnosis, increased with 486 Euro after IBS was diagnosed, whereas for secondary care patients, these costs increased with 2328 Euro. Total health care costs remained higher in the three years after the initial diagnosis when the patient is treated in secondary care, compared to primary care. This increase was significant for hospital specialist costs and medications, but not for GP contacts. For controls, there was no significant difference in mean total annual health costs in the three years before and the three years after the diagnosis and also no significant difference in cost increases between both primary- and secondary-care control patients. Total healthcare costs per patient substantially increase after a diagnosis of IBS and IBS related costs are significantly higher when patients are treated in secondary-care compared to primary-care. IBS patients should be treated in primary-care where possible, not only because guidelines recommend this from a quality of care viewpoint, but also to optimize use of health care resources. Referral should be restricted to those patients with alarm symptoms, with ill-matching symptoms, or other cases of diagnostic uncertainty.
Williams, Marianne; Barclay, Yvonne; Benneyworth, Rosie; Gore, Steve; Hamilton, Zoe; Matull, Rudi; Phillips, Iain; Seamark, Leah; Staveley, Kate; Thole, Steve; Greig, Emma
2016-10-01
Irritable bowel syndrome (IBS) costs the National Health Service almost £12 million per annum. Despite national guidelines advising primary care management, these have failed to stem secondary care referrals of patients with likely IBS for unnecessary and costly assessment and investigation without necessarily achieving resolution of their symptoms. In 2011, an integrated team from primary and secondary care developed a business case using baseline data to create a Somerset-wide IBS pathway using Clinical Commissioning Group funding. This provided face-to-face general practitioners (GP) education, developed a diagnostic pathway and funded faecal calprotectin (FC) testing to exclude inflammatory pathology for patients aged 16-45 years with likely IBS and no alarm symptoms. For those with FC≤50 μg/g, we provided a management algorithm and community-based dietetic treatment. Audit results measured usage and outcomes from FC testing, changes in patterns and costs of new patients reviewed in gastroenterology outpatients and dietetic IBS treatment outcomes. The proportion of new patient slots used reduced from 14.3% to 8.7% over 10 months while overall costs reduced by 25% for patients with no alarm symptoms and likely IBS aged 16-45 years. FC results confirmed research findings with no inflammatory pathology, if FC≤50 μg/g over 2 years. 63% of patients had satisfactory control of their IBS after specialist dietetic input with 74% reporting improved quality of life. The combination of GP education, providing diagnosis and management pathways, using FC to exclude inflammatory pathology and providing an effective treatment for patients with likely IBS appeared successful in our pilot. This proved cost-effective, reduced secondary care involvement and improved patient care.
Everitt, Hazel; Moss-Morris, Rona; Sibelli, Alice; Tapp, Laura; Coleman, Nicholas; Yardley, Lucy; Smith, Peter; Little, Paul
2013-04-21
Many patients with IBS suffer on-going symptoms. The evidence base is poor for IBS drugs but they are widely prescribed and advised in Guidelines. Cognitive Behavioural Therapy (CBT) can be helpful, but availability is poor in the NHS. We developed a web-based CBT self-management programme (Regul8) in partnership with patients and trialled it and common IBS medications in an exploratory factorial RCT to test trial procedures and provide information for a larger trial. Patients, 16 to 60 years, with IBS symptoms fulfilling Rome III criteria were recruited via GP practices and randomised to over-encapsulated mebeverine, methylcellulose or placebo for 6 weeks and to 1 of 3 website conditions: Regul8 with a nurse telephone session and email support, Regul8 with minimal email support, or no website. 135 patients recruited from 26 GP practices. Mean IBS SSS score 241.9 (sd 87.7), IBS-QOL 64 (sd 20) at baseline. 91% follow-up at 12 weeks. Mean IBS SSS decreased by 35 points from baseline to 12 weeks. There was no significant difference in IBS SSS or IBS-QOL score between medication or website groups at 12 weeks, or in medication groups at 6 weeks, or IBS-QOL in website groups at 6 weeks. However, IBS SSS at 6 weeks was lower in the No website group than the website groups (IBS SSS no website =162.8 (95% CI 137.4-188.3), website 197.0 (172.4 - 221.7), Website + telephone support 208.0 (183.1-233.0) p = 0.037). This exploratory study demonstrates feasibility and high follow-up rates and provides information for a larger trial. Primary outcomes (IBS SS and IBS QOL) did not reach significance at 6 or 12 weeks, apart from IBS SSS being lower in the no-website group at 6 weeks - this disappeared by 12 weeks. Improved Enablement suggests patients with access to the Regul8 website felt better able to cope with their symptoms than the non-website group. Improved SGA score in the Regul8 groups may indicate some overall improvement not captured on other measures. ClinicalTrials.gov Identifier (NCT number): NCT00934973.
Rubak, Peter; Kristensen, Steen D; Hvas, Anne-Mette
2017-06-01
Immature platelets may contain more platelet enzymes such as cyclooxygenase (COX)-1 and COX-2 than mature platelets. Patients with immune thrombocytopenia (ITP) have a higher fraction of immature platelets and can therefore be utilized as a biological model for investigating COX-1 and COX-2 platelet expression. The aims were to develop flow cytometric assays for platelet COX-1 and COX-2 and to investigate the COX-1 and COX-2 platelet expression, platelet turnover, and platelet glycoproteins in ITP patients (n = 10) compared with healthy individuals (n = 30). Platelet count and platelet turnover parameters (mean platelet volume (MPV), immature platelet fraction (IPF), and immature platelet count (IPC)) were measured by flow cytometry (Sysmex XE-5000). Platelet COX-1, COX-2, and the glycoproteins (GP)IIb, IX, Ib, Ia, and IIIa were all analyzed by flow cytometry (Navios) and expressed as median fluorescence intensity. COX analyses were performed in both whole blood and platelet rich plasma (PRP), whereas platelet glycoproteins were analyzed in whole blood only. ITP patients had significantly lower platelet count (55 × 10 9 /L) than healthy individuals (240 × 10 9 /L, p < 0.01), but a higher MPV (p = 0.03) and IPF (p < 0.01). IPC was similar for the two groups (p = 0.74). PRP had significantly lower MPV (p < 0.01) and significantly higher platelet count and IPC (both p-values <0.03) when compared with whole blood. IPF was similar for PRP and whole blood (p = 0.18). COX-1 expression was 10 times higher and COX-2 expression was 50% higher in PRP than in whole blood (p COX-1 < 0.01, p COX-2 < 0.01). Platelet COX-1 expression was higher in ITP patients than healthy individuals using whole blood (p COX-1 < 0.01) and PRP, though this was nonsignificant in PRP (p COX-1 = 0.17). In ITP patients, positive correlations were found between platelet turnover and COX-1 expression (all p-values <0.01, rho = 0.80-0.94), whereas healthy individuals showed significant though weaker correlations between platelet turnover and COX-1 and COX-2 expressions (all p-values <0.03, rho = 0.44-0.71). GPIIb, IX, and Ib expression was increased in ITP patients compared with healthy individuals (all p-values < 0.03). GPIIb, IX, Ib, and IIIa showed positive correlations with platelet turnover in ITP patients (all p-values <0.02, rho = 0.71-0.94), but weak and nonsignificant correlations in healthy individuals (all p-values >0.14, rho = 0.11-0.28). In conclusion, ITP patients expressed higher COX-1 and platelet glycoprotein levels than healthy individuals. COX-1 and platelet glycoproteins demonstrated positive correlations with platelet turnover in ITP patients. In healthy individuals, COX-1 and COX-2 expression correlated positively with platelet turnover. PRP was more sensitive compared with whole blood as regards determination of COX. Therefore, PRP is the recommended matrix for investigating COX-1 and COX-2 in platelets.
Poon, Man-Chiu; d'Oiron, Roseline
2018-06-07
Glanzmann's thrombasthenia (GT) and Bernard-Soulier's syndrome (BSS) are well-understood congenital bleeding disorders, showing defect/deficiency of platelet glycoprotein (GP) IIb/IIIa (integrin αIIbβ3) and GPIb-IX-V complexes respectively, with relevant clinical, laboratory, biochemical, and genetic features. Following platelet transfusion, affected patients may develop antiplatelet antibodies (to human leukocyte antigen [HLA], and/or αIIbβ3 in GT or GPIb-IX in BSS), which may render future platelet transfusion ineffective. Anti-αIIbβ3 and anti-GPIb-IX may also cross the placenta during pregnancy to cause thrombocytopenia and bleeding in the fetus/neonate. This review will focus particularly on the better studied GT to illustrate the natural history and complications of platelet alloimmunization. BSS will be more briefly discussed. Platelet transfusion, if unavoidable, should be given judiciously with good indications. Patients following platelet transfusion, and women during and after pregnancy, should be monitored for the development of platelet antibodies. There is now a collection of data suggesting the safety and effectiveness of recombinant activated factor VII in the management of affected patients with platelet antibodies. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Williams, Marianne; Barclay, Yvonne; Benneyworth, Rosie; Gore, Steve; Hamilton, Zoe; Matull, Rudi; Phillips, Iain; Seamark, Leah; Staveley, Kate; Thole, Steve; Greig, Emma
2016-01-01
Background Irritable bowel syndrome (IBS) costs the National Health Service almost £12 million per annum. Despite national guidelines advising primary care management, these have failed to stem secondary care referrals of patients with likely IBS for unnecessary and costly assessment and investigation without necessarily achieving resolution of their symptoms. Methods In 2011, an integrated team from primary and secondary care developed a business case using baseline data to create a Somerset-wide IBS pathway using Clinical Commissioning Group funding. This provided face-to-face general practitioners (GP) education, developed a diagnostic pathway and funded faecal calprotectin (FC) testing to exclude inflammatory pathology for patients aged 16–45 years with likely IBS and no alarm symptoms. For those with FC≤50 μg/g, we provided a management algorithm and community-based dietetic treatment. Audit results measured usage and outcomes from FC testing, changes in patterns and costs of new patients reviewed in gastroenterology outpatients and dietetic IBS treatment outcomes. Results The proportion of new patient slots used reduced from 14.3% to 8.7% over 10 months while overall costs reduced by 25% for patients with no alarm symptoms and likely IBS aged 16–45 years. FC results confirmed research findings with no inflammatory pathology, if FC≤50 μg/g over 2 years. 63% of patients had satisfactory control of their IBS after specialist dietetic input with 74% reporting improved quality of life. Conclusions The combination of GP education, providing diagnosis and management pathways, using FC to exclude inflammatory pathology and providing an effective treatment for patients with likely IBS appeared successful in our pilot. This proved cost-effective, reduced secondary care involvement and improved patient care. PMID:27761233
Bayer, Wibke; Tenbusch, Matthias; Lietz, Ruth; Johrden, Lena; Schimmer, Simone; Uberla, Klaus; Dittmer, Ulf; Wildner, Oliver
2010-02-01
We present a new type of adenoviral vector that both encodes and displays a vaccine antigen on the capsid, thus combining in itself gene-based and protein vaccination; this vector resulted in an improved vaccination outcome in the Friend virus (FV) model. For presentation of the envelope protein gp70 of Friend murine leukemia virus on the adenoviral capsid, gp70 was fused to the adenovirus capsid protein IX. When compared to vaccination with conventional FV Env- and Gag-encoding adenoviral vectors, vaccination with the adenoviral vector that encodes and displays pIX-gp70 combined with an FV Gag-encoding vector resulted in significantly improved protection against systemic FV challenge infection, with highly controlled viral loads in plasma and spleen. This improved protection correlated with improved neutralizing antibody titers and stronger CD4(+) T-cell responses. Using a vector that displays gp70 without encoding it, we found that while the antigen display on the capsid alone was sufficient to induce high levels of binding antibodies, in vivo expression was necessary for the induction of neutralizing antibodies. This new type of adenovirus-based vaccine could be a valuable tool for vaccination.
Triflavin, an Arg‐Gly‐Asp‐containing Peptide, Inhibits Tumor Cell‐induced Platelet Aggregation
Sheu, Joen R.; Lin, Chao H.; Peng, Hui C.; Teng, Che M.
1993-01-01
In this study, we examined the effect of triflavin, an Arg‐Gly‐Asp (RGD)‐containing snake venom peptide, on human cervical carcinoma (HeLa) cell‐ and B16‐F10 mouse melanoma cell‐induced platelet aggregation (TCIPA) in heparinized platelet‐rich plasma. TCIPA appears to play an important role in the development of certain experimental tumor metastases. Two ADP‐scavenging agents, apyrase (10 U/ml) and creatine phosphate (CP) (5 mM)/creatine phosphokinase (CPK) (5 U/ml) completely inhibited B16‐F10 TCIPA, but hirudin (5 U/ml) had no effect. In contrast, apyrase and CP/CPK did not inhibit HeLa TCIPA while hirudin completely inhibited it. Furthermore, HeLa cells initially induced platelet aggregation and then blood coagulation at a later stage. In addition, HeLa cells shortened, in a concentration‐dependent manner, the recalcification time of normal as well as factor VIII‐ and IX‐deficient human plasma, but did not affect the recalciflcation time of factor VII‐deficient plasma. This suggests that HeLa TCIPA occurs via activation of the extrinsic pathway, probably owing to tumor cell expression of tissue factor‐like activity. HeLa cell‐induced thrombin generation was confirmed by detection of amidolytic activity towards a chromogenic substrate, S‐2238 (H‐D‐Phe‐Pip‐Arg‐p‐NA). Triflavin and GRGDS inhibited, in a dose‐dependent manner, TCIPA caused by either cell line. On a molar basis, triflavin was 10,000–30,000 times more potent than GRGDS in this regard. Moreover, monoclonal antibodies raised against glycoprotein (GP) IIb/IIIa complex (i.e., 7E3 and AP2) and against GP Ib (i.e., AP1) completely inhibited HeLa TCIPA. 7E3 and AP2 inhibited B16‐F10 TCIPA by up to 80% whereas AP1 showed only 30% inhibition of B16‐F10 TCIPA. In conclusion, the inhibitory effect of triflavin on HeLa and B16‐F10 TCIPA may be mediated principally by the binding of triflavin to the fibrinogen receptor associated with GP IIb/IIIa complex on the platelet surface. However, GP Ib is also involved in HeLa TCIPA as thrombin formation is the key factor in triggering platelet aggregation caused by HeLa cells. PMID:8226281
Dionysopoulos, Dimitrios; Koliniotou-Koumpia, Eugenia; Helvatzoglou-Antoniades, Maria; Kotsanos, Nikolaos
2016-01-01
To determine the ability of 5 contemporary fluoride-releasing restoratives and 3 fluoride-releasing adhesives to inhibit enamel demineralisation surrounding restorations, and the associations between inhibition and the levels of fluoride released from these materials. Five fluoride-releasing restoratives (Fuji IX GP, Ketac N100, Dyract Extra, Beautifil II and Wave) and 3 fluoride-releasing adhesives (Stae, Prime & Bond NT and Fluoro Bond II) were investigated. Eight disks of each material were prepared. Fluoride release was measured daily using a fluoride-ion-selective electrode for 15 days. Twenty-four cavities for each group were restored with a restorative and an adhesive. Specimens were subjected to thermal stress and stored for 30 days in saline solution. After a 15-day pH-cycling regimen, two 150-μm-thick sections were derived from each specimen. Enamel lesion depth was measured at 0, 100, and 200 μm from each restoration's margin via polarised light microscopy. Of the restoratives investigated, Fuji IX GP released the most fluoride. The fluoride-releasing restoratives tested exhibited shallower enamel lesions than did the control group at all distances tested (p < 0.05). Fuji IX GP yielded significantly lower enamel lesion depth than did the other experimental materials. The depths of enamel lesions did not differ significantly when comparing restoratives applied with a fluoride-releasing adhesive with those applied with a non-fluoride-releasing adhesive. The fluoride-releasing materials tested reduced enamel demineralisation but to different extents, depending on their levels of fluoride release. Fluoride-releasing adhesives did not influence enamel lesion formation.
Daifalla, Lamia E; Mobarak, Enas H
2015-11-01
This study was conducted to evaluate the effect of ultrasound application on the surface microhardness (VHN) and diametral tensile strength (DTS) of three high viscous glass-ionomer restorative materials (HVGIRMs). For each test (VHN and DTS), a total of 180 specimens were prepared from three HVGIRMs (Ketac-Molar Aplicap, Fuji IX GP Fast, and ChemFil Rock). Specimens of each material (n = 60) were further subdivided into three subgroups (n = 20) according to the setting modality whether ultrasound (20 or 40 s) was applied during setting or not (control). Specimens within each subgroup were then equally divided (n = 10) and tested at 24 h or 28 days. For the VHN measurement, five indentations, with a 200 g load and a dwell time for 20 s, were made on the top surface of each specimen. The DTS test was done using Lloyd Testing machine at a cross-head speed of 0.5 mm/min. Ultrasound application had no significant effect on the VHN. Fuji IX GP Fast revealed the highest VHN value, followed by Ketac-Molar Aplicap, and the least was recorded for ChemFil Rock. Fuji IX GP Fast and Ketac-Molar Aplicap VHN values were significantly increased by time. ChemFil Rock recorded the highest DTS value at 24 h and was the only material that showed significant improvement with both US application times. However, this improvement did not sustain till 28 days. The ultrasound did not enhance the surface microhardness, but its positive effect on the diametral tensile strength values was material and time dependent.
Daifalla, Lamia E.; Mobarak, Enas H.
2014-01-01
This study was conducted to evaluate the effect of ultrasound application on the surface microhardness (VHN) and diametral tensile strength (DTS) of three high viscous glass-ionomer restorative materials (HVGIRMs). For each test (VHN and DTS), a total of 180 specimens were prepared from three HVGIRMs (Ketac-Molar Aplicap, Fuji IX GP Fast, and ChemFil Rock). Specimens of each material (n = 60) were further subdivided into three subgroups (n = 20) according to the setting modality whether ultrasound (20 or 40 s) was applied during setting or not (control). Specimens within each subgroup were then equally divided (n = 10) and tested at 24 h or 28 days. For the VHN measurement, five indentations, with a 200 g load and a dwell time for 20 s, were made on the top surface of each specimen. The DTS test was done using Lloyd Testing machine at a cross-head speed of 0.5 mm/min. Ultrasound application had no significant effect on the VHN. Fuji IX GP Fast revealed the highest VHN value, followed by Ketac-Molar Aplicap, and the least was recorded for ChemFil Rock. Fuji IX GP Fast and Ketac-Molar Aplicap VHN values were significantly increased by time. ChemFil Rock recorded the highest DTS value at 24 h and was the only material that showed significant improvement with both US application times. However, this improvement did not sustain till 28 days. The ultrasound did not enhance the surface microhardness, but its positive effect on the diametral tensile strength values was material and time dependent. PMID:26644916
Johansson, Per A; Farup, Per G; Bracco, Andrea; Vandvik, Per O
2010-03-17
Irritable bowel syndrome (IBS) is associated with other disorders (comorbidity), reduced quality of life and increased use of health resources. We aimed to explore the impact of comorbidity on cost of health care in patients with IBS in general practice. In this cohort study 208 consecutive patients with IBS (Rome II) were recruited. Sociodemographic data, IBS symptoms, and comorbidity (somatic symptoms, organic diseases and psychiatric disorders) were assessed at baseline. Based on a follow up interview after 6-9 months and use of medical records, IBS and non-IBS related health resource use were measured as consultations, hospitalisations, use of medications and alternative health care products and sick leave days. Costs were calculated by national tariffs and reported in Norwegian Kroner (NOK, 1 EURO equals 8 NOK). Multivariate analyses were performed to identify predictors of costs. A total of 164 patients (mean age 52 years, 69% female, median duration of IBS 17 years) were available at follow up, 143 patients (88%) had consulted their GP of whom 31 (19%) had consulted for IBS. Mean number of sick- leave days for IBS and comorbidity were 1.7 and 16.3 respectively (p < 0.01), costs related to IBS and comorbidity were 954 NOK and 14854 NOK respectively (p < 0.001). Age, organic diseases and somatic symptoms, but not IBS severity, were significant predictors for total costs. Costs for health resource use among patients with IBS in general practice were largely explained by comorbidity, which generated ten times the costs for IBS.
2010-01-01
Background Irritable bowel syndrome (IBS) is associated with other disorders (comorbidity), reduced quality of life and increased use of health resources. We aimed to explore the impact of comorbidity on cost of health care in patients with IBS in general practice. Methods In this cohort study 208 consecutive patients with IBS (Rome II) were recruited. Sociodemographic data, IBS symptoms, and comorbidity (somatic symptoms, organic diseases and psychiatric disorders) were assessed at baseline. Based on a follow up interview after 6-9 months and use of medical records, IBS and non-IBS related health resource use were measured as consultations, hospitalisations, use of medications and alternative health care products and sick leave days. Costs were calculated by national tariffs and reported in Norwegian Kroner (NOK, 1 EURO equals 8 NOK). Multivariate analyses were performed to identify predictors of costs. Results A total of 164 patients (mean age 52 years, 69% female, median duration of IBS 17 years) were available at follow up, 143 patients (88%) had consulted their GP of whom 31 (19%) had consulted for IBS. Mean number of sick- leave days for IBS and comorbidity were 1.7 and 16.3 respectively (p < 0.01), costs related to IBS and comorbidity were 954 NOK and 14854 NOK respectively (p < 0.001). Age, organic diseases and somatic symptoms, but not IBS severity, were significant predictors for total costs. Conclusion Costs for health resource use among patients with IBS in general practice were largely explained by comorbidity, which generated ten times the costs for IBS. PMID:20233451
Everitt, Hazel A; Moss-Morris, Rona E; Sibelli, Alice; Tapp, Laura; Coleman, Nicholas S; Yardley, Lucy; Smith, Peter W; Little, Paul S
2010-11-18
IBS affects 10-22% of the UK population. Abdominal pain, bloating and altered bowel habit affect quality of life, social functioning and time off work. Current GP treatment relies on a positive diagnosis, reassurance, lifestyle advice and drug therapies, but many suffer ongoing symptoms.A recent Cochrane review highlighted the lack of research evidence for IBS drugs. Neither GPs, nor patients have good evidence to inform prescribing decisions. However, IBS drugs are widely used: In 2005 the NHS costs were nearly £10 million for mebeverine and over £8 million for fibre-based bulking agents. CBT and self-management can be helpful, but poor availability in the NHS restricts their use. We have developed a web-based CBT self-management programme, Regul8, based on an existing evidence based self-management manual and in partnership with patients. This could increase access with minimal increased costs. The aim is to undertake a feasibility factorial RCT to assess the effectiveness of the commonly prescribed medications in UK general practice for IBS: mebeverine (anti-spasmodic) and methylcellulose (bulking-agent) and Regul8, the CBT based self-management website.135 patients aged 16 to 60 years with IBS symptoms fulfilling Rome III criteria, recruited via GP practices, will be randomised to 1 of 3 levels of the drug condition: mebeverine, methylcellulose or placebo for 6 weeks and to 1 of 3 levels of the website condition, Regul8 with a nurse telephone session and email support, Regul8 with minimal email support, or no website, thus creating 9 groups. Irritable bowel symptom severity scale and IBS-QOL will be measured at baseline, 6 and 12 weeks as the primary outcomes. An intention to treat analysis will be undertaken by ANCOVA for a factorial trial. This pilot will provide valuable information for a larger trial. Determining the effectiveness of commonly used drug treatments will help patients and doctors make informed treatment decisions regarding drug management of IBS symptoms, enabling better targeting of treatment. A web-based self-management CBT programme for IBS developed in partnership with patients has the potential to benefit large numbers of patients with low cost to the NHS. Assessment of the amount of email or therapist support required for the website will enable economic analysis to be undertaken.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vijayasaradhi, S.; Doskoch, P.M.; Houghton, A.N.
1991-10-01
A 75-kDa melanosomal glycoprotein (gp75) is the product of a gene that maps to the b (brown) locus, a genetic locus that determines coat color in the mouse. The b locus is conserved (88% identity) between mouse and human. The mouse monoclonal antibody TA99 was used to study the biosynthesis and processing of gp75. gp75 was synthesized as a 55-kDa polypeptide, glycosylated by addition and processing of five or more Asn-linked carbohydrate chains through the cis and trans Golgi, and transported to melanosomes as a mature 75-kDa form. Synthesis and processing of gp75 was rapid (T{sub 1/2} < 30 min),more » and early steps in processing were required for efficient export of gp75 was quite stable in the melanosome. Studies with inhibitors of steps in oligosaccharide processing showed that alternative forms of gp75 were generated during trimming reactions by mannosidase IA/IB and that further maturation resulted in the two mature forms of gp75. The authors purpose that the kinetics of biosynthesis and processing reflect events in the biogenesis and maturation of melanosomes.« less
Dobbin, A; Dobbin, J; Ross, S C; Graham, C; Ford, M J
2013-01-01
Irritable bowel syndrome (IBS) is a common disorder associated with profoundly impaired quality of life and emotional distress. The management of refractory IBS symptoms remains challenging and non-pharmacological therapeutic approaches have been shown to be effective. We compared brief interventions with biofeedback and hypnotherapy in women referred by their GP with refractory IBS symptoms. Patients were randomised to one of two treatment groups, biofeedback or hypnotherapy, delivered as three one-hour sessions over 12 weeks. Symptom assessments were undertaken using validated, self-administered questionnaires. Two of the 128 consecutive IBS patients suitable for the study declined to consider nonpharmacological therapy and 29 patients did not attend beyond the first session. Of the 97 patients randomised into the study, 21 failed to attend the therapy session; 15 of 76 patients who attended for therapy dropped out before week 12 post-therapy. The mean (SD) change in IBS symptom severity score 12 weeks post-treatment in the biofeedback group was -116.8 (99.3) and in the hypnotherapy group -58.0 (101.1), a statistically significant difference between groups (difference=-58.8, 95% confidence interval [CI] for difference [-111.6, -6.1], p=0.029). In 61 patients with refractory IBS, biofeedback and hypnotherapy were equally effective at improving IBS symptom severity scores, total non-gastrointestinal symptom scores and anxiety and depression ratings during 24 weeks follow-up. Biofeedback may prove to be the more cost-effective option as it requires less expertise.
Coating glass-ionomer cements with a nanofilled resin.
Bonifácio, Clarissa Calil; Werner, Arie; Kleverlaan, Cornelis Johanes
2012-12-01
The objective of this study was to investigate the effect of a nanofilled resin coat on the flexural strength (FS) and the early wear (after 50,000 and 200,000 cycles) of the glass-ionomer cements Fuji IX GP Extra (FIXE) and Ketac Molar Aplicap (KM). Specimens were prepared and half of them were coated with G-Coat plus. The uncoated specimens were used as controls. Flexural strength (n = 10) was evaluated after 24 h using a 3-point bending test on a universal testing machine (ISO 9917-2). Wear (n = 20) was evaluated after 50,000 and 200,000 cycles using the ACTA wear machine. One-way, two-way ANOVA and Tukey post-hoc tests were used to analyze differences in FS and wear. For FIXE the coat significantly increased the FS and the wear along the two time spans. KM did not show a significant difference in FS with the coat. Improvements in wear were observed only after 50,000 cycles. Based on these laboratory results, it is concluded that G-coat Plus is indicated in association with GP IX Extra with the aim to improve the mechanical properties of the former. However, this study is limited to a short-term observation.
Eberhard, D; Tora, L; Egly, J M; Grummt, I
1993-09-11
TIF-IB is a transcription factor which interacts with the mouse ribosomal gene promoter and nucleates the formation of an initiation complex containing RNA polymerase I (Pol I). We have purified this factor to near homogeneity and demonstrate that TIF-IB is a large complex (< 200 kDa) which contains several polypeptides. One of the subunits present in this protein complex is the TATA-binding protein (TBP) as revealed by copurification of TIF-IB activity and TBP over different chromatographic steps including immunoaffinity purification. In addition to TBP, three tightly associated proteins (TAFs-I) with apparent molecular weights of 95, 68, and 48 kDa are contained in this multimeric complex. This subunit composition is similar--but not identical--to the analogous human factor SL1. Depletion of TBP from TIF-IB-containing fractions by immunoprecipitation eliminates TIF-IB activity. Neither TBP alone nor fractions containing other TBP complexes are capable of substituting for TIF-IB activity. Therefore, TIF-IB is a unique complex with Pol I-specific TAFs distinct from other TBP-containing complexes. The identification of TBP as an integral part of the murine rDNA promoter-specific transcription initiation factor extends the previously noted similarity of transcriptional initiation by the three nuclear RNA polymerases and underscores the importance of TAFs in determining promoter specificity.
Eberhard, D; Tora, L; Egly, J M; Grummt, I
1993-01-01
TIF-IB is a transcription factor which interacts with the mouse ribosomal gene promoter and nucleates the formation of an initiation complex containing RNA polymerase I (Pol I). We have purified this factor to near homogeneity and demonstrate that TIF-IB is a large complex (< 200 kDa) which contains several polypeptides. One of the subunits present in this protein complex is the TATA-binding protein (TBP) as revealed by copurification of TIF-IB activity and TBP over different chromatographic steps including immunoaffinity purification. In addition to TBP, three tightly associated proteins (TAFs-I) with apparent molecular weights of 95, 68, and 48 kDa are contained in this multimeric complex. This subunit composition is similar--but not identical--to the analogous human factor SL1. Depletion of TBP from TIF-IB-containing fractions by immunoprecipitation eliminates TIF-IB activity. Neither TBP alone nor fractions containing other TBP complexes are capable of substituting for TIF-IB activity. Therefore, TIF-IB is a unique complex with Pol I-specific TAFs distinct from other TBP-containing complexes. The identification of TBP as an integral part of the murine rDNA promoter-specific transcription initiation factor extends the previously noted similarity of transcriptional initiation by the three nuclear RNA polymerases and underscores the importance of TAFs in determining promoter specificity. Images PMID:8414971
2013-01-01
Background Estimates of the prevalence of irritable bowel syndrome (IBS) vary widely, and a large proportion of patients report having consulted their general practitioner (GP). In patients with new onset gastrointestinal symptoms in primary care it might be possible to predict those at risk of persistent symptoms. However, one of the difficulties is identifying patients within primary care. GPs use a variety of Read Codes to describe patients presenting with IBS. Furthermore, in a qualitative study, exploring GPs’ attitudes and approaches to defining patients with IBS, GPs appeared reluctant to add the IBS Read Code to the patient record until more serious conditions were ruled out. Consequently, symptom codes such as 'abdominal pain’, 'diarrhoea’ or 'constipation’ are used. The aim of the current study was to investigate the prevalence of recorded consultations for IBS and to explore the symptom profile of patients with IBS using data from the Salford Integrated Record (SIR). Methods This was a database study using the SIR, a local patient sharing record system integrating primary, community and secondary care information. Records were obtained for a cohort of patients with gastrointestinal disorders from January 2002 to December 2011. Prevalence rates, symptom recording, medication prescribing and referral patterns were compared for three patient groups (IBS, abdominal pain (AP) and Inflammatory Bowel Disease (IBD)). Results The prevalence of IBS (age standardised rate: 616 per year per 100,000 population) was much lower than expected compared with that reported in the literature. The majority of patients (69%) had no gastrointestinal symptoms recorded in the year prior to their IBS. However a proportion of these (22%) were likely to have been prescribed NICE guideline recommended medications for IBS in that year. The findings for AP and IBD were similar. Conclusions Using Read Codes to identify patients with IBS may lead to a large underestimate of the community prevalence. The IBS diagnostic Read Code was rarely applied in practice. There are similarities with many other medically unexplained symptoms which are typically difficult to diagnose in clinical practice. PMID:24295337
Harkness, Elaine F; Grant, Laura; O'Brien, Sarah J; Chew-Graham, Carolyn A; Thompson, David G
2013-12-02
Estimates of the prevalence of irritable bowel syndrome (IBS) vary widely, and a large proportion of patients report having consulted their general practitioner (GP). In patients with new onset gastrointestinal symptoms in primary care it might be possible to predict those at risk of persistent symptoms. However, one of the difficulties is identifying patients within primary care. GPs use a variety of Read Codes to describe patients presenting with IBS. Furthermore, in a qualitative study, exploring GPs' attitudes and approaches to defining patients with IBS, GPs appeared reluctant to add the IBS Read Code to the patient record until more serious conditions were ruled out. Consequently, symptom codes such as 'abdominal pain', 'diarrhoea' or 'constipation' are used. The aim of the current study was to investigate the prevalence of recorded consultations for IBS and to explore the symptom profile of patients with IBS using data from the Salford Integrated Record (SIR). This was a database study using the SIR, a local patient sharing record system integrating primary, community and secondary care information. Records were obtained for a cohort of patients with gastrointestinal disorders from January 2002 to December 2011. Prevalence rates, symptom recording, medication prescribing and referral patterns were compared for three patient groups (IBS, abdominal pain (AP) and Inflammatory Bowel Disease (IBD)). The prevalence of IBS (age standardised rate: 616 per year per 100,000 population) was much lower than expected compared with that reported in the literature. The majority of patients (69%) had no gastrointestinal symptoms recorded in the year prior to their IBS. However a proportion of these (22%) were likely to have been prescribed NICE guideline recommended medications for IBS in that year. The findings for AP and IBD were similar. Using Read Codes to identify patients with IBS may lead to a large underestimate of the community prevalence. The IBS diagnostic Read Code was rarely applied in practice. There are similarities with many other medically unexplained symptoms which are typically difficult to diagnose in clinical practice.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hinerman, Jennifer M.; Dignam, J. David; Mueser, Timothy C.
2012-04-05
The bacteriophage T4 gp59 helicase assembly protein (gp59) is required for loading of gp41 replicative helicase onto DNA protected by gp32 single-stranded DNA-binding protein. The gp59 protein recognizes branched DNA structures found at replication and recombination sites. Binding of gp32 protein (full-length and deletion constructs) to gp59 protein measured by isothermal titration calorimetry demonstrates that the gp32 protein C-terminal A-domain is essential for protein-protein interaction in the absence of DNA. Sedimentation velocity experiments with gp59 protein and gp32ΔB protein (an N-terminal B-domain deletion) show that these proteins are monomers but form a 1:1 complex with a dissociation constant comparable withmore » that determined by isothermal titration calorimetry. Small angle x-ray scattering (SAXS) studies indicate that the gp59 protein is a prolate monomer, consistent with the crystal structure and hydrodynamic properties determined from sedimentation velocity experiments. SAXS experiments also demonstrate that gp32ΔB protein is a prolate monomer with an elongated A-domain protruding from the core. Moreover, fitting structures of gp59 protein and the gp32 core into the SAXS-derived molecular envelope supports a model for the gp59 protein-gp32ΔB protein complex. Our earlier work demonstrated that gp59 protein attracts full-length gp32 protein to pseudo-Y junctions. A model of the gp59 protein-DNA complex, modified to accommodate new SAXS data for the binary complex together with mutational analysis of gp59 protein, is presented in the accompanying article (Dolezal, D., Jones, C. E., Lai, X., Brister, J. R., Mueser, T. C., Nossal, N. G., and Hinton, D. M. (2012) J. Biol. Chem. 287, 18596–18607).« less
Singla, Teena; Pandit, I.K.; Srivastava, Nikhil; Gugnani, Neeraj; Gupta, Monika
2011-01-01
Aim To evaluate the microleakage of recently available glass ionomer based restorative materials (GC Fuji IX GP, GC Fuji VII, and Dyract) and compare their microleakage with the previously existing glass ionomer restorative materials (GC Fuji II LC) in primary and permanent teeth. Method One hundred and fifty (75 + 75) non-carious deciduous and permanent teeth were restored with glass ionomer based restorative materials after making class I cavities. Samples were subjected to thermocycling after storing in distilled water for 24 h. Two coats of nail polish were applied 1 mm short of restorative margins and samples sectioned buccolingually after storing in methylene blue dye for 24 h. Microleakage was assessed using stereomicroscope. Result Significant differences (P < 0.05) were found when inter group comparisons were done. Except when GC Fuji VII (Group III) was compared with GC Fuji II LC (Group II) and Dyract (Group IV), non-significant differences (P > 0.05) were observed. It was found that there was no statistically significant difference when the means of microleakage of primary teeth were compared with those of permanent teeth. Conclusions GC Fuji IX GP showed maximum microleakage and GC Fuji VII showed least microleakage. PMID:23960526
Gu, Linlin; Krendelchtchikova, Valentina; Krendelchtchikov, Alexandre; Farrow, Anitra L; Derdeyn, Cynthia A; Matthews, Qiana L
2016-01-01
Adenoviral (Ad) vectors in combination with the "Antigen Capsid-Incorporation" strategy have been applied in developing HIV-1 vaccines, due to the vectors׳ abilities in incorporating and inducing immunity of capsid-incorporated antigens. Variable loop 2 (V2)-specific antibodies were suggested in the RV144 trial to correlate with reduced HIV-1 acquisition, which highlights the importance of developing novel HIV-1 vaccines by targeting the V2 loop. Therefore, the V2 loop of HIV-1 has been incorporated into the Ad capsid protein. We generated adenovirus serotype 5 (Ad5) vectors displaying variable loop 2 (V2) of HIV-1 gp120, with the "Antigen Capsid-Incorporation" strategy. To assess the incorporation capabilities on hexon hypervariable region1 (HVR1) and protein IX (pIX), 20aa or full length (43aa) of V2 and V1V2 (67aa) were incorporated, respectively. Immunizations with the recombinant vectors significantly generated antibodies against both linear and discontinuous V2 epitopes. The immunizations generated durable humoral immunity against V2. This study will lead to more stringent development of various serotypes of adenovirus-vectored V2 vaccine candidates, based on breakthroughs regarding the immunogenicity of V2. Copyright © 2015. Published by Elsevier Inc.
NASA Astrophysics Data System (ADS)
Saurabh, Suman; Sahoo, Anil Kumar; Maiti, Prabal K.
2016-10-01
Experiments and computational studies have established that de-protonated dendrimers (SPL7013 and PAMAM) act as entry-inhibitors of HIV. SPL7013 based Vivagel is currently under clinical development. The dendrimer binds to gp120 in the gp120-CD4 complex, destabilizes it by breaking key contacts between gp120 and CD4 and prevents viral entry into target cells. In this work, we provide molecular details and energetics of the formation of the SPL7013-gp120-CD4 ternary complex and decipher modes of action of the dendrimer in preventing viral entry. It is also known from experiments that the dendrimer binds weakly to gp120 that is not bound to CD4. It binds even more weakly to the CD4-binding region of gp120 and thus cannot directly block gp120-CD4 complexation. In this work, we examine the feasibility of dendrimer binding to the gp120-binding region of CD4 and directly blocking gp120-CD4 complex formation. We find that the process of the dendrimer binding to CD4 can compete with gp120-CD4 binding due to comparable free energy change for the two processes, thus creating a possibility for the dendrimer to directly block gp120-CD4 complexation by binding to the gp120-binding region of CD4.
Geiss, G K; Radebaugh, C A; Paule, M R
1997-11-14
Acanthamoeba castellanii transcription initiation factor-IB (TIF-IB) is the TATA-binding protein-containing transcription factor that binds the rRNA promoter to form the committed complex. Minor groove-specific drugs inhibit TIF-IB binding, with higher concentrations needed to disrupt preformed complexes because of drug exclusion by bound TIF-IB. TIF-IB/DNA interactions were mapped by hydroxyl radical and uranyl nitrate footprinting. TIF-IB contacts four minor grooves in its binding site. TIF-IB and DNA wrap around each other in a right-handed superhelix of high pitch, so the upstream and downstream contacts are on opposite faces of the helix. Dimethyl sulfate protection assays revealed limited contact with a few guanines in the major groove. This detailed analysis suggests significant DNA conformation dependence of the interaction.
Sato, R; Oshio, H; Koike, H; Inoue, Y; Yoshida, S; Takahashi, N
1991-06-01
Porphyrin accumulation in excised cucumber cotyledons (Cucumis sativus L.) treated with a N-phenylimide S-23142 (N-[4-chloro-2-fluoro-5-propargyloxyphenyl]-3,4,5,6- tetrahydrophthalimide) and a diphenylether acifluorfen-ethyl (ethyl-5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitro benzoic acid) was studied. Most of the accumulated porphyrins were found in the membrane fractions of 6,000g and 30,000g pellets, forming a complex with a membrane polypeptide. The complex was solubilized with 1% n-dodecyl beta-d-maltoside and its molecular mass was estimated to be 63,000 and 66,000 daltons by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel permeation high performance liquid chromatography (HPLC), respectively. The polypeptide also existed in untreated cotyledons but had little protoporphyrin IX. The complex was also formed in vitro by mixing the 30,000g pellets from untreated cotyledons and authentic protoporphyrin IX. However, protoporphyrin IX formed the complex specifically with the 63,000 dalton polypeptide and not with the other proteins both in vivo and in vitro. At least four fluorescent porphyrins, including protoporphyrin IX, were found in the acetone extract of the cotyledons by HPLC using a reversed phase column. Protoporphyrin IX was one of the two porphyrins that formed the complex. These results suggest that S-23142 and acifluorfenethyl enhance the accumulation of protoporphyrin IX, which forms the complex with the membrane protein.
Salústio, P J; Cabral-Marques, H M; Costa, P C; Pinto, J F
2011-05-01
Mixtures containing ibuprofen (IB) complexed with β-cyclodextrin (βCD) obtained by two complexation methods [suspension/solution (with water removed by air stream, spray- and freeze-drying) and kneading technique] were processed into pharmaceutical dosage forms (minitablets and capsules). Powders (IB, βCD and IBβCD) were characterized for moisture content, densities (true and bulk), angle of repose and Carr's index, X-ray and NMR. From physical mixtures and IBβCD complexes without other excipients were prepared 2.5-mm-diameter minitablets and capsules. Minitablets were characterized for the energy of compaction, tensile strength, friability, density and IB release (at pH 1.0 and 7.2), whereby capsules were characterized for IB release. The results from the release of IB were analyzed using different parameters, namely, the similarity factor (f(2)), the dissolution efficiency (DE) and the amounts released at a certain time (30, 60 and 180 min) and compared statistically (α=0.05). The release of IB from the minitablets showed no dependency on the amount of water used in the formation of the complexes. Differences were due to the compaction force used or the presence of a shell for the capsules. The differences observed were mostly due to the characteristics of the particles (dependent on the method considered on the formation of the complexes) and neither to the dosage form nor to the complex of the IB. Copyright © 2011 Elsevier B.V. All rights reserved.
Intracellular Trafficking of Clostridium perfringens Iota-Toxin b
Umezaki, Mariko; Tashiro, Ryo; Oda, Masataka; Kobayashi, Keiko; Shibutani, Masahiro; Takagishi, Teruhisa; Ishidoh, Kazumi; Fukuda, Mitsunori; Sakurai, Jun
2012-01-01
Clostridium perfringens iota-toxin is composed of an enzymatic component (Ia) and a binding component (Ib). Ib binds to a cell surface receptor, undergoes oligomerization in lipid rafts, and binds Ia. The resulting complex is then endocytosed. Here, we show the intracellular trafficking of iota-toxin. After the binding of the Ib monomer with cells at 4°C, oligomers of Ib formed at 37°C and later disappeared. Immunofluorescence staining of Ib revealed that the internalized Ib was transported to early endosomes. Some Ib was returned to the plasma membrane through recycling endosomes, whereas the rest was transported to late endosomes and lysosomes for degradation. Degraded Ib was delivered to the plasma membrane by an increase in the intracellular Ca2+ concentration caused by Ib. Bafilomycin A1, an endosomal acidification inhibitor, caused the accumulation of Ib in endosomes, and both nocodazole and colchicine, microtubule-disrupting agents, restricted Ib's movement in the cytosol. These results indicated that an internalized Ia and Ib complex was delivered to early endosomes and that subsequent delivery of Ia to the cytoplasm occurs mainly in early endosomes. Ib was either sent back to the plasma membranes through recycling endosomes or transported to late endosomes and lysosomes for degradation. Degraded Ib was transported to plasma membranes. PMID:22825447
The MYStIX Infrared-Excess Source Catalog
NASA Astrophysics Data System (ADS)
Povich, Matthew S.; Kuhn, Michael A.; Getman, Konstantin V.; Busk, Heather A.; Feigelson, Eric D.; Broos, Patrick S.; Townsley, Leisa K.; King, Robert R.; Naylor, Tim
2013-12-01
The Massive Young Star-Forming Complex Study in Infrared and X-rays (MYStIX) project provides a comparative study of 20 Galactic massive star-forming complexes (d = 0.4-3.6 kpc). Probable stellar members in each target complex are identified using X-ray and/or infrared data via two pathways: (1) X-ray detections of young/massive stars with coronal activity/strong winds or (2) infrared excess (IRE) selection of young stellar objects (YSOs) with circumstellar disks and/or protostellar envelopes. We present the methodology for the second pathway using Spitzer/IRAC, 2MASS, and UKIRT imaging and photometry. Although IRE selection of YSOs is well-trodden territory, MYStIX presents unique challenges. The target complexes range from relatively nearby clouds in uncrowded fields located toward the outer Galaxy (e.g., NGC 2264, the Flame Nebula) to more distant, massive complexes situated along complicated, inner Galaxy sightlines (e.g., NGC 6357, M17). We combine IR spectral energy distribution (SED) fitting with IR color cuts and spatial clustering analysis to identify IRE sources and isolate probable YSO members in each MYStIX target field from the myriad types of contaminating sources that can resemble YSOs: extragalactic sources, evolved stars, nebular knots, and even unassociated foreground/background YSOs. Applying our methodology consistently across 18 of the target complexes, we produce the MYStIX IRE Source (MIRES) Catalog comprising 20,719 sources, including 8686 probable stellar members of the MYStIX target complexes. We also classify the SEDs of 9365 IR counterparts to MYStIX X-ray sources to assist the first pathway, the identification of X-ray-detected stellar members. The MIRES Catalog provides a foundation for follow-up studies of diverse phenomena related to massive star cluster formation, including protostellar outflows, circumstellar disks, and sequential star formation triggered by massive star feedback processes.
Structures of Ebola virus GP and sGP in complex with therapeutic antibodies.
Pallesen, Jesper; Murin, Charles D; de Val, Natalia; Cottrell, Christopher A; Hastie, Kathryn M; Turner, Hannah L; Fusco, Marnie L; Flyak, Andrew I; Zeitlin, Larry; Crowe, James E; Andersen, Kristian G; Saphire, Erica Ollmann; Ward, Andrew B
2016-08-08
The Ebola virus (EBOV) GP gene encodes two glycoproteins. The major product is a soluble, dimeric glycoprotein (sGP) that is secreted abundantly. Despite the abundance of sGP during infection, little is known regarding its structure or functional role. A minor product, resulting from transcriptional editing, is the transmembrane-anchored, trimeric viral surface glycoprotein (GP). GP mediates attachment to and entry into host cells, and is the intended target of antibody therapeutics. Because large portions of sequence are shared between GP and sGP, it has been hypothesized that sGP may potentially subvert the immune response or may contribute to pathogenicity. In this study, we present cryo-electron microscopy structures of GP and sGP in complex with GP-specific and GP/sGP cross-reactive antibodies undergoing human clinical trials. The structure of the sGP dimer presented here, in complex with both an sGP-specific antibody and a GP/sGP cross-reactive antibody, permits us to unambiguously assign the oligomeric arrangement of sGP and compare its structure and epitope presentation to those of GP. We also provide biophysical evaluation of naturally occurring GP/sGP mutations that fall within the footprints identified by our high-resolution structures. Taken together, our data provide a detailed and more complete picture of the accessible Ebolavirus glycoprotein landscape and a structural basis to evaluate patient and vaccine antibody responses towards differently structured products of the GP gene.
Mutant botrocetin-2 inhibits von Willebrand factor-induced platelet agglutination.
Matsui, T; Hori, A; Hamako, J; Matsushita, F; Ozeki, Y; Sakurai, Y; Hayakawa, M; Matsumoto, M; Fujimura, Y
2017-03-01
Essentials Botrocetin-2 (Bot2) binds to von Willebrand factor (VWF) and induces platelet agglutination. We identified Bot2 residues that are required for binding to VWF and glycoprotein (GP) Ib. We produced a mutant Bot2 that binds to VWF but inhibits platelet agglutination. Mutant Bot2 could be used as a potential anti-thrombotic reagent to block VWF-GPIb interaction. Background Botrocetin-2 (Bot2) is a botrocetin-like protein composed of α and β subunits that have been cloned from the snake Bothrops jararaca. Bot2 binds specifically to von Willebrand factor (VWF), and the complex induces glycoprotein (GP) Ib-dependent platelet agglutination. Objectives To exploit Bot2's VWF-binding capacity in order to attempt to create a mutant Bot2 that binds to VWF but inhibits platelet agglutination. Methods and Results Several point mutations were introduced into Bot2 cDNA, and the recombinant protein (recombinant Bot2 [rBot2]) was purified on an anti-botrocetin column. The mutant rBot2 with either Ala at Asp70 in the β subunit (Aspβ70Ala), or Argβ115Ala and Lysβ117Ala, showed reduced platelet agglutination-inducing activity. rBot2 with Aspβ70Ala showed little binding activity towards immobilized VWF on an ELISA plate, whereas rBot2 with Argβ115Ala/Lysβ117Ala showed reduced binding activity towards GPIb (glycocalicin) after forming a complex with VWF. rBot2 point-mutated to oppositely charged Glu at both Argβ115 and Lysβ117 showed normal binding activity towards VWF but no platelet-agglutinating activity. Furthermore, this doubly mutated protein inhibited ristocetin-induced or high shear stress-induced platelet aggregation, and restrained thrombus formation under flow conditions. Conclusions Asp70 in the β subunit of botrocetin is important for VWF binding, and Arg115 and Lys117 in the β subunit are essential for interaction with GPIb. Doubly mutated rBot2, with Argβ115Glu and Lysβ117Glu, repels GPIb and might have potential as an antithrombotic reagent that specifically blocks VWF function. This is the first report on an artificial botrocetin that can inhibit the VWF-GPIb interaction. © 2017 International Society on Thrombosis and Haemostasis.
Folding of a salivary intrinsically disordered protein upon binding to tannins.
Canon, Francis; Ballivian, Renaud; Chirot, Fabien; Antoine, Rodolphe; Sarni-Manchado, Pascale; Lemoine, Jérôme; Dugourd, Philippe
2011-05-25
We used ion mobility spectrometry to explore conformational adaptability of intrinsically disordered proteins bound to their targets in complex mixtures. We investigated the interactions between a human salivary proline-rich protein IB5 and a model of wine and tea tannin: epigallocatechin gallate (EgCG). Collisional cross sections of naked IB5 and IB5 complexed with N = 1-15 tannins were recorded. The data demonstrate that IB5 undergoes an unfolded to folded structural transition upon binding with EgCG.
Effects of dentin surface treatments on shear bond strength of glass-ionomer cements
Poggio, Claudio; Beltrami, Riccardo; Scribante, Andrea; Colombo, Marco; Lombardini, Marco
2014-01-01
Summary Aim The aim of this in vitro study was to evaluate the effect of different surface treatments on shear bond strength of a conventional glass-ionomer cement (GIC) and a resin-modified glass-ionomer cement (RMGIC) to dentin. Materials and methods 80 bovine permanent incisors were used. 40 cylindrical specimens of a GIC (Fuji IX GP Extra) and 40 cylindrical specimens of a RMGIC (Fuji II LC) were attached to the dentin. The teeth were then randomly assigned to 8 groups of equal size (n=10), 4 for every type of glass-ionomer cement, corresponding to type of dentin surface treatments. Group 1: GC Cavity Conditioner; Group 2: 37% phosphoric acid gel; Group 3: Clearfil SE Bond; Group 4: no dentin conditioning (control). The specimens were placed in a universal testing machine (Model 3343, Instron Corp., Canton, Mass., USA) and subsequently tested for shear bond strength (MPa). Results ANOVA showed the presence of significant differences among the various groups. Post hoc Tukey test showed different values of shear bond strength for Fuji IX GP Extra and for Fuji II LC. The different conditioners variably influence the adhesion of the glass-ionomer cements tested. Conclusions. RMGIC shear bond to dentin was higher than GIC. The use of a Self-etch adhesive system improved the shear bond strength values of RMGIC and lowered the shear bond strength values of GIC significantly. PMID:24753797
Al-Khouri, Anna Maria; Paule, Marvin R.
2002-01-01
In the small, free-living amoeba Acanthamoeba castellanii, rRNA transcription requires, in addition to RNA polymerase I, a single DNA-binding factor, transcription initiation factor IB (TIF-IB). TIF-IB is a multimeric protein that contains TATA-binding protein (TBP) and four TBP-associated factors that are specific for polymerase I transcription. TIF-IB is required for accurate and promoter-specific initiation of rRNA transcription, recruiting and positioning the polymerase on the start site by protein-protein interaction. In A. castellanii, partially purified TIF-IB can form a persistent complex with the ribosomal DNA (rDNA) promoter while homogeneous TIF-IB cannot. An additional factor, TIF-IE, is required along with homogeneous TIF-IB for the formation of a stable complex on the rDNA core promoter. We show that TIF-IE by itself, however, does not bind to the rDNA promoter and thus differs in its mechanism from the upstream binding factor and upstream activating factor, which carry out similar complex-stabilizing functions in vertebrates and yeast, respectively. In addition to its presence in impure TIF-IB, TIF-IE is found in highly purified fractions of polymerase I, with which it associates. Renaturation of polypeptides excised from sodium dodecyl sulfate-polyacrylamide gels showed that a 141-kDa polypeptide possesses all the known activities of TIF-IE. PMID:11784852
Al-Khouri, Anna Maria; Paule, Marvin R
2002-02-01
In the small, free-living amoeba Acanthamoeba castellanii, rRNA transcription requires, in addition to RNA polymerase I, a single DNA-binding factor, transcription initiation factor IB (TIF-IB). TIF-IB is a multimeric protein that contains TATA-binding protein (TBP) and four TBP-associated factors that are specific for polymerase I transcription. TIF-IB is required for accurate and promoter-specific initiation of rRNA transcription, recruiting and positioning the polymerase on the start site by protein-protein interaction. In A. castellanii, partially purified TIF-IB can form a persistent complex with the ribosomal DNA (rDNA) promoter while homogeneous TIF-IB cannot. An additional factor, TIF-IE, is required along with homogeneous TIF-IB for the formation of a stable complex on the rDNA core promoter. We show that TIF-IE by itself, however, does not bind to the rDNA promoter and thus differs in its mechanism from the upstream binding factor and upstream activating factor, which carry out similar complex-stabilizing functions in vertebrates and yeast, respectively. In addition to its presence in impure TIF-IB, TIF-IE is found in highly purified fractions of polymerase I, with which it associates. Renaturation of polypeptides excised from sodium dodecyl sulfate-polyacrylamide gels showed that a 141-kDa polypeptide possesses all the known activities of TIF-IE.
Zhao, Pengkun; Liu, Hongyu; Deng, Hongbing; Xiao, Ling; Qin, Caiqin; Du, Yumin; Shi, Xiaowen
2014-11-01
In this study, the complex pH and electro responsive system made of chitosan hydrogel with embedded mesoporous silica nanoparticles (MSNs) was evaluated as a tunable drug release system. As a model drug, ibuprofen (IB) was used; its adsorption in MSNs was evidenced by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and thermogravimetric analysis (TG). In order to prepare the complex drug release system, the loaded particles IB-MSNs were dispersed in chitosan solution and then the complex IB-MSNs/chitosan film of 2mm thickness was deposited as a hydrogel on the titanium electrode. The codeposition of components was performed under a negative biasing of the titanium electrode at -0.75 mA/cm2 current density during 30 min. The IB release from the IB-MSNs/chitosan hydrogel film was studied as dependent on pH of the release media and electrical conditions applied to the titanium plate. When incubating the complex hydrogel film in buffers with different pH, the IB release followed a near zero-order profile, though its kinetics varied. Compared to the spontaneous IB release from the hydrogel in 0.9% NaCl solution (at 0 V), the application of negative biases to the coated titanium plate had profound effluences on the release behavior. The release was retarded when -1.0 V was applied, but a faster kinetics was observed at -5.0 V. These results imply that a rapid, mild and facile electrical process for covering titanium implants by complex IB-MSNs/chitosan hydrogel films can be used for controlled drug delivery applications. Copyright © 2014 Elsevier B.V. All rights reserved.
Psychosocial factors at work and in every day life are associated with irritable bowel syndrome.
Faresjö, Ashild; Grodzinsky, Ewa; Johansson, Saga; Wallander, Mari-Ann; Timpka, Toomas; Akerlind, Ingemar
2007-01-01
The etiology of irritable bowel syndrome (IBS) tends to be complex and multi-factorial and there is still a lack of understanding of how different psychosocial factors are associated with the syndrome. Our aim was to examine the occurrence of psychosocial and behavioural factors among patients diagnosed with IBS in primary care. The study had an epidemiological population-based case-control design comparing 347 IBS cases to 1041 age and sex matched controls from the general population. A survey was directed to cases and controls based on validated questions asking for mood status, job strain, family history of IBS, and sleeping habits as well as education, nutritional and exercise habits and medication. In multivariate analyses, independent associations were found between IBS and lack of influence on work planning, a family history of IBS, anxiety, and sleeping disturbances. Important factors associated with IBS diagnosis among females were anxiety as well as family history of IBS and lack of co-determination at work. For males, only lack of influence on working pace and family history of IBS remained independently associated with an IBS diagnosis. The causal associations of the complex risk factor panorama for IBS warrants further study. This study indicates that there should be a special focus on investigating the psychosocial working conditions and their associations to IBS.
Molecular mechanism of transcription inhibition by phage T7 gp2 protein.
Mekler, Vladimir; Minakhin, Leonid; Sheppard, Carol; Wigneshweraraj, Sivaramesh; Severinov, Konstantin
2011-11-11
Escherichia coli T7 bacteriophage gp2 protein is a potent inhibitor of host RNA polymerase (RNAP). gp2 inhibits formation of open promoter complex by binding to the β' jaw, an RNAP domain that interacts with downstream promoter DNA. Here, we used an engineered promoter with an optimized sequence to obtain and characterize a specific promoter complex containing RNAP and gp2. In this complex, localized melting of promoter DNA is initiated but does not propagate to include the point of the transcription start. As a result, the complex is transcriptionally inactive. Using a highly sensitive RNAP beacon assay, we performed quantitative real-time measurements of specific binding of the RNAP-gp2 complex to promoter DNA and various promoter fragments. In this way, the effect of gp2 on RNAP interaction with promoters was dissected. As expected, gp2 greatly decreased RNAP affinity to downstream promoter duplex. However, gp2 also inhibited RNAP binding to promoter fragments that lacked downstream promoter DNA that interacts with the β' jaw. The inhibition was caused by gp2-mediated decrease of the RNAP binding affinity to template and non-template strand segments of the transcription bubble downstream of the -10 promoter element. The inhibition of RNAP interactions with single-stranded segments of the transcription bubble by gp2 is a novel effect, which may occur via allosteric mechanism that is set in motion by the gp2 binding to the β' jaw. Copyright © 2011 Elsevier Ltd. All rights reserved.
Radebaugh, C A; Kubaska, W M; Hoffman, L H; Stiffler, K; Paule, M R
1998-10-16
The fundamental transcription initiation factor (TIF) for ribosomal RNA expression by eukaryotic RNA polymerase I, TIF-IB, has been purified to near homogeneity from Acanthamoeba castellanii using standard techniques. The purified factor consists of the TATA-binding protein and four TATA-binding protein-associated factors with relative molecular weights of 145,000, 99,000, 96,000, and 91,000. This yields a calculated native molecular weight of 460, 000, which compares well with its mass determined by scanning transmission electron microscopy (493,000) and its sedimentation rate, which is close to RNA polymerase I (515,000). Both impure and nearly homogeneous TIF-IB exhibit an apparent equilibrium dissociation constant of 56 +/- 3 pM. However, although impure TIF-IB can form a promoter-DNA complex resistant to challenge by other promoter-containing DNAs, near homogeneous TIF-IB cannot do so. An additional transcription factor, dubbed TIF-IE, restores the ability of near homogeneous TIF-IB to sequester DNA into a committed complex.
Intracellular Mannose Binding Lectin Mediates Subcellular Trafficking of HIV-1 gp120 in Neurons
Teodorof, C; Divakar, S; Soontornniyomkij, B; Achim, CL; Kaul, M; Singh, KK
2014-01-01
Human immunodeficiency virus -1 (HIV-1) enters the brain early during infection and leads to severe neuronal damage and central nervous system impairment. HIV-1 envelope glycoprotein 120 (gp120), a neurotoxin, undergoes intracellular trafficking and transport across neurons; however mechanisms of gp120 trafficking in neurons are unclear. Our results show that mannose binding lectin (MBL) that binds to the N-linked mannose residues on gp120, participates in intravesicular packaging of gp120 in neuronal subcellular organelles and also in subcellular trafficking of these vesicles in neuronal cells. Perinuclear MBL:gp120 vesicular complexes were observed and MBL facilitated the subcellular trafficking of gp120 via the endoplasmic reticulum (ER) and Golgi vesicles. The functional carbohydrate recognition domain of MBL was required for perinuclear organization, distribution and subcellular trafficking of MBL:gp120 vesicular complexes. Nocodazole, an agent that depolymerizes the microtubule network, abolished the trafficking of MBL:gp120 vesicles, suggesting that these vesicular complexes were transported along the microtubule network. Live cell imaging confirmed the association of the MBL:gp120 complexes with dynamic subcellular vesicles that underwent trafficking in neuronal soma and along the neurites. Thus, our findings suggest that intracellular MBL mediates subcellular trafficking and transport of viral glycoproteins in a microtubule-dependent mechanism in the neurons. PMID:24825317
Intracellular mannose binding lectin mediates subcellular trafficking of HIV-1 gp120 in neurons.
Teodorof, C; Divakar, S; Soontornniyomkij, B; Achim, C L; Kaul, M; Singh, K K
2014-09-01
Human immunodeficiency virus-1 (HIV-1) enters the brain early during infection and leads to severe neuronal damage and central nervous system impairment. HIV-1 envelope glycoprotein 120 (gp120), a neurotoxin, undergoes intracellular trafficking and transport across neurons; however mechanisms of gp120 trafficking in neurons are unclear. Our results show that mannose binding lectin (MBL) that binds to the N-linked mannose residues on gp120, participates in intravesicular packaging of gp120 in neuronal subcellular organelles and also in subcellular trafficking of these vesicles in neuronal cells. Perinuclear MBL:gp120 vesicular complexes were observed and MBL facilitated the subcellular trafficking of gp120 via the endoplasmic reticulum (ER) and Golgi vesicles. The functional carbohydrate recognition domain of MBL was required for perinuclear organization, distribution and subcellular trafficking of MBL:gp120 vesicular complexes. Nocodazole, an agent that depolymerizes the microtubule network, abolished the trafficking of MBL:gp120 vesicles, suggesting that these vesicular complexes were transported along the microtubule network. Live cell imaging confirmed the association of the MBL:gp120 complexes with dynamic subcellular vesicles that underwent trafficking in neuronal soma and along the neurites. Thus, our findings suggest that intracellular MBL mediates subcellular trafficking and transport of viral glycoproteins in a microtubule-dependent mechanism in the neurons. Published by Elsevier Inc.
Wong, Connie H. Y.; Jenne, Craig N.; Petri, Björn; Chrobok, Navina L.; Kubes, Paul
2016-01-01
Using intravital imaging of the liver, we unveil a collaborative role for platelets with Kupffer cells (KCs) in eradicating bloodborne bacterial infections. Under basal conditions, platelets via glycoprotein Ib (GPIb) formed transient “touch-and-go” interactions with von Willebrand factor (vWF) constitutively expressed on KCs. Bacteria, such as Bacillus cereus and Methicillin-resistant Staphylococcus aureus (MRSA), were rapidly caught by KCs and triggered platelets to switch from “touch-and-go” to sustained GPIIb-mediated adhesion on the KC surface to encase the bacterium. Infected GpIbα−/− mice demonstrated increased endothelial and KC damage, leading to increased fluid leakage, significant polycythemia and rapid mortality. This study identifies a novel surveillance mechanism of intravascular macrophage by platelets that rapidly converts to a critical host response against bloodborne bacteria. PMID:23770641
Yap, Adrian U J; Ng, J J; Yap, S H; Teo, C K
2004-01-01
This study investigated the surface finish of resin-modified (Fuji II LC, GC) and highly viscous (Fuji IX GP Fast, GC) glass ionomer cements after treatment with three one-step finishing/polishing systems (One-Gloss [OG], Shofu; Pogo [PG], Dentsply; Sof-Lex Brush [SB], 3M-ESPE). The surface roughness obtained was compared to that using a matrix strip [MS], a two-step rubber abrasive (CompoSite [CS], Shofu) and a graded abrasive disk (Super Snap [SS], Shofu) system. Eight specimens (3-mm long x 3-mm wide x 2-mm deep) of each material were made for the various treatment groups. With the exception of the MS group, all groups were roughened with 320 grit grinding paper using a lapping device prior to finishing/polishing with the different systems. The mean surface roughness (microm) was measured with a profilometer. Data was subjected to ANOVA/Scheffe's tests at significance level 0.05. Mean Ra ranged from 0.13 to 1.04 microm for Fuji II LC and 0.14 to 0.81 for Fuji IX GP. For both materials, the smoothest surface was obtained with MS and the roughest with OG. Depending on the materials, the surface finish produced by PG and SB was superior or comparable to that obtained with CS and SS. The effectiveness of one-step systems, when used to finish/polish resin-modified and highly viscous glass ionomer cements, is product dependent.
Rincheval, Vincent; Lelek, Mickael; Gault, Elyanne; Bouillier, Camille; Sitterlin, Delphine; Blouquit-Laye, Sabine; Galloux, Marie; Zimmer, Christophe; Eleouet, Jean-François; Rameix-Welti, Marie-Anne
2017-09-15
Infection of cells by respiratory syncytial virus induces the formation of cytoplasmic inclusion bodies (IBs) where all the components of the viral RNA polymerase complex are concentrated. However, the exact organization and function of these IBs remain unclear. In this study, we use conventional and super-resolution imaging to dissect the internal structure of IBs. We observe that newly synthetized viral mRNA and the viral transcription anti-terminator M2-1 concentrate in IB sub-compartments, which we term "IB-associated granules" (IBAGs). In contrast, viral genomic RNA, the nucleoprotein, the L polymerase and its cofactor P are excluded from IBAGs. Live imaging reveals that IBAGs are highly dynamic structures. Our data show that IBs are the main site of viral RNA synthesis. They further suggest that shortly after synthesis in IBs, viral mRNAs and M2-1 transiently concentrate in IBAGs before reaching the cytosol and suggest a novel post-transcriptional function for M2-1.Respiratory syncytial virus (RSV) induces formation of inclusion bodies (IBs) sheltering viral RNA synthesis. Here, Rincheval et al. identify highly dynamic IB-associated granules (IBAGs) that accumulate newly synthetized viral mRNA and the viral M2-1 protein but exclude viral genomic RNA and RNA polymerase complexes.
Koehler, Anson V; Haydon, Shane R; Jex, Aaron R; Gasser, Robin B
2016-06-01
In a long-term program to monitor pathogens in water catchments serving the City of Melbourne in the State of Victoria in Australia, we detected and genetically characterised Cryptosporidium and Giardia in faecal samples from various animals in nine water reservoir areas over a period of 4 years (July 2011 to November 2015). This work was conducted using PCR-based single-strand conformation polymorphism (SSCP) and phylogenetic analyses of portions of the small subunit of ribosomal RNA (SSU) and 60 kDa glycoprotein (gp60) genes for Cryptosporidium, and triose-phosphate isomerase (tpi) gene for Giardia. The prevalence of Cryptosporidium was 1.62 % (69 of 4,256 samples); 25 distinct sequence types were defined for pSSU, and six for gp60 which represented C. hominis (genotype Ib - subgenotype IbA10G2), C. cuniculus (genotype Vb - subgenotypes VbA26, and VbA25), and C. canis, C. fayeri, C. macropodum, C. parvum, C. ryanae, Cryptosporidium sp. "duck" genotype, C. suis and C. ubiquitum as well as 12 novel SSU sequence types. The prevalence of Giardia was 0.31 % (13 of 4,256 samples); all three distinct tpi sequence types defined represented assemblage A of G. duodenalis. Of the 34 sequence types (genotypes) characterized here, five and one have been recorded previously for Cryptosporidium and Giardia, respectively, from humans. Novel genotypes of Cryptosporidium and Giardia were recorded for SSU (n = 12), gp60 (n = 4) and tpi (n = 1); the zoonotic potential of these novel genotypes is presently unknown. Future work will continue to monitor the prevalence of Cryptosporidium and Giardia genotypes in animals in these catchments, and expand investigations to humans. Nucleotide sequences reported in this paper are available in the GenBank database under accession nos. KU531647-KU531718.
Wu, Shasha; Kunhi Veedu, Hari Prasad; Lhatoo, Samden D; Koubeissi, Mohamad Z; Miller, Jonathan P; Lüders, Hans O
2014-05-01
To assess the role of ictal baseline shifts (IBS) and ictal high-frequency oscillations (iHFOs) in intracranial electroencephalography (EEG) presurgical evaluation by analysis of the spatial and temporal relationship of IBS, iHFOs with ictal conventional stereo-electroencephalography (icEEG) in mesial temporal lobe seizures (MTLS). We studied 15 adult patients with medically refractory MTLS who underwent monitoring with depth electrodes. Seventy-five ictal EEG recordings at 1,000 Hz sampling rate were studied. Visual comparison of icEEG, IBS, and iHFOs were performed using Nihon-Kohden Neurofax systems (acquisition range 0.016-300 Hz). Each recorded ictal EEG was analyzed with settings appropriate for displaying icEEG, IBS, and iHFOs. IBS and iHFOs were observed in all patients and in 91% and 81% of intracranial seizures, respectively. IBS occurred before (22%), at (57%), or after (21%) icEEG onset. In contrast, iHFOs occurred at (30%) or after (70%) icEEG onset. The onset of iHFOs was 11.5 s later than IBS onset (p < 0.0001). All of the earliest onset of IBS and 70% of the onset of iHFOs overlapped with the ictal onset zone (IOZ). Compared with iHFOs, interictal HFOs (itHFOs) were less correlated with IOZ. In contrast to icEEG, IBS and iHFOs had smaller spatial distributions in 70% and 100% of the seizures, respectively. An IBS dipole was observed in 66% of the seizures. Eighty-seven percent of the dipoles had a negative pole at the anterior/medial part of amygdala/hippocampus complex (A-H complex) and a positive pole at the posterior/lateral part of the A-H complex. The results suggest that evaluation of IBS and iHFOs, in addition to routine icEEG, helps in more accurately defining the IOZ. This study also shows that the onset and the spatial distribution of icEEG, IBS, and iHFOs do not overlap, suggesting that they reflect different cellular or network dynamics. Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.
1990-09-01
231 Harry L. Frisch PART V: IONOMERS/STRUCTURE SMALL ANGLE X - RAY SCATTERING ON POLY(ETHYLENE-METHACRYLIC ACID) LEAD AND LEAD SULFIDE IONOMERS 237...E.J. Kramer, R.J. Composto, R.S. Stein, T.P. Russell, G.P. Felcher, A. Mansour, and A. Karim * td:tt Papet Vil X - RAY REFLECTIVITY AND FLUORESCENCE...Sammann DETERMINATION OF PARTICLE SIZE OF A DISPERSED PHASE BY SMALL-ANGLE X - RAY SCATTERING 413 Frank C. Wilson *Invited Paper ix SYNTHESIS AND
Constellation's First Flight Test: Ares I-X
NASA Technical Reports Server (NTRS)
Davis, Stephan R.; Askins, Bruce R.
2010-01-01
On October 28, 2009, NASA launched Ares I-X, the first flight test of the Constellation Program that will send human beings to the Moon and beyond. This successful test is the culmination of a three-and-a-half-year, multi-center effort to design, build, and fly the first demonstration vehicle of the Ares I crew launch vehicle, the successor vehicle to the Space Shuttle. The suborbital mission was designed to evaluate the atmospheric flight characteristics of a vehicle dynamically similar to Ares I; perform a first stage separation and evaluate its effects; characterize and control roll torque; stack, fly, and recover a solid-motor first stage testing the Ares I parachutes; characterize ground, flight, and reentry environments; and develop and execute new ground hardware and procedures. Built from existing flight and new simulator hardware, Ares I-X integrated a Shuttle-heritage four-segment solid rocket booster for first stage propulsion, a spacer segment to simulate a five-segment booster, Peacekeeper axial engines for roll control, and Atlas V avionics, as well as simulators for the upper stage, crew module, and launch abort system. The mission leveraged existing logistical and ground support equipment while also developing new ones to accommodate the first in-line rocket for flying astronauts since the Saturn IB last flew from Kennedy Space Center (KSC) in 1975. This paper will describe the development and integration of the various vehicle and ground elements, from conception to stacking in KSC s Vehicle Assembly Building; hardware performance prior to, during, and after the launch; and preliminary lessons and data gathered from the flight. While the Constellation Program is currently under review, Ares I-X has and will continue to provide vital lessons for NASA personnel in taking a vehicle concept from design to flight.
Arenavirus Stable Signal Peptide Is the Keystone Subunit for Glycoprotein Complex Organization
Bederka, Lydia H.; Bonhomme, Cyrille J.; Ling, Emily L.
2014-01-01
ABSTRACT The rodent arenavirus glycoprotein complex encodes a stable signal peptide (SSP) that is an essential structural component of mature virions. The SSP, GP1, and GP2 subunits of the trimeric glycoprotein complex noncovalently interact to stud the surface of virions and initiate arenavirus infectivity. Nascent glycoprotein production undergoes two proteolytic cleavage events: first within the endoplasmic reticulum (ER) to cleave SSP from the remaining precursor GP1/2 (glycoprotein complex [GPC]) glycoprotein and second within the Golgi stacks by the cellular SKI-1/S1P for GP1/2 processing to yield GP1 and GP2 subunits. Cleaved SSP is not degraded but retained as an essential glycoprotein subunit. Here, we defined functions of the 58-amino-acid lymphocytic choriomeningitis virus (LCMV) SSP in regard to glycoprotein complex processing and maturation. Using molecular biology techniques, confocal microscopy, and flow cytometry, we detected SSP at the plasma membrane of transfected cells. Further, we identified a sorting signal (FLLL) near the carboxyl terminus of SSP that is required for glycoprotein maturation and trafficking. In the absence of SSP, the glycoprotein accumulated within the ER and was unable to undergo processing by SKI-1/S1P. Mutation of this highly conserved FLLL motif showed impaired glycoprotein processing and secretory pathway trafficking, as well as defective surface expression and pH-dependent membrane fusion. Immunoprecipitation of SSP confirmed an interaction between the signal peptide and the GP2 subunit; however, mutations within this FLLL motif disrupted the association of the GP1 subunit with the remaining glycoprotein complex. PMID:25352624
Bonding of contemporary glass ionomer cements to dentin.
Yip, H K; Tay, F R; Ngo, H C; Smales, R J; Pashley, D H
2001-09-01
The objective of this study was to investigate the microtensile bond strength (microTBS) of contemporary glass ionomer cements (GIC) to sound coronal dentin. Three specimen teeth were prepared for each material tested: Fuji IX GP (GC), ChemFlex (Dentsply) and Ketac-Molar Aplicap (ESPE). GIC buildups were made according to the manufacturers' instructions. After being stored at 37 degrees C, 100% humidity for 24h, the teeth were vertically sectioned into 1x1mm beams for microTBS evaluation. Representative fractured beams were prepared for scanning (SEM) and transmission electron microscopic (TEM) examination. Results of the microTBS test were: Fuji IX GP (12.4+/-8.6MPa), ChemFlex (15.0+/-9.3MPa) and Ketac-Molar Aplicap (11.4+/-7.7MPa). One-way ANOVA and a multiple comparison test showed that ChemFlex had a statistically higher microTBS (p<0.05). SEM fractographic analysis showed that the predominant failure modes were interfacial and mixed failures. The GIC side of the fractured beams revealed dehydration cracks, a high level of porosity, and voids with an eggshell-like crust. TEM analysis of the demineralized dentin sides of the fractured beams revealed the presence of an intermediate layer along the GIC-dentin interface. This zone was present on the fractured dentin surface in the case of interfacial failure, and beneath GIC remnants in specimens that exhibited a mixed failure mode. The findings suggest that the bonding of GIC to dentin is not weak and that the microTBS values probably represent the weak yield strengths of GICs under tension.
Selimović-Dragaš, Mediha; Hasić-Branković, Lajla; Korać, Fehim; Đapo, Nermin; Huseinbegović, Amina; Kobašlija, Sedin; Lekić, Meliha; Hatibović-Kofman, Šahza
2013-08-01
Fluoride release is important characteristic of glass-ionomer cements. Quantity of fluoride ions released from the glass-ionomer cements has major importance in definition of their biological activity. The objectives of this study were to define the quantity of fluoride ions released from the experimental glass-ionomer cements and to define the effect of fluoride ions released from the experimental glass-ionomer cements on their cytotoxicity. Concentrations of the fluoride ions released in the evaluated glass-ionomer cements were measured indirectly, by the fluoride-selective WTW, F500 electrode potential, combined with reference R503/D electrode. Statistical analyses of F-ion concentrations released by all glass-ionomers evaluated at two time points, after 8 and after 24 hours, show statistically higher fluoride releases from RMGICs: Vitrebond, Fuji II LC and Fuji Plus, when compared to conventional glass-ionomer cements: Fuji Triage, Fuji IX GP Fast and Ketac Silver, both after 8 and after 24 hours. Correlation coefficient between concentrations of fluoride ion released by evaluated glass-ionomer cements and cytotoxic response of UMR-106 osteoblast cell-line are relatively high, but do not reach levels of biological significance. Correlation between concentrations of fluoride ion released and cytotoxic response of NIH3T3 mouse fibroblast cell line after 8 hours is high, positive and statistically significant for conventional GICs, Fuji Triage and Fuji IX GP Fast, and RMGIC, Fuji II LC. Statistically significant Correlation coefficient between concentrations of fluoride ion released and cytotoxic response of NIH3T3 cell line after 24 hours is defined for RMGIC Fuji II LC only.
Identification of a major polypeptide of the nuclear pore complex
1982-01-01
The nuclear pore complex is a prominent structural component of the nuclear envelope that appears to regulate nucleoplasmic molecular movement. Up to now, none of its polypeptides have been defined. To identify possible pore complex proteins, we fractionated rat liver nuclear envelopes and microsomal membranes with strong protein perturbants into peripheral and intrinsic membrane proteins, and compared these fractions on SDS gels. From this analysis, we identified a prominent 190-kilodalton intrinsic membrane polypeptide that occurs specifically in nuclear envelopes. Lectin binding studies indicate that this polypeptide (gp 190) is the major nuclear envelope glycoprotein. Upon treatment of nuclear envelopes with Triton X-100, gp 190 remains associated with a protein substructure of the nuclear envelope consisting of pore complexes and nuclear lamina. We prepared monospecific antibodies to gp 190 for immunocytochemical localization. Immunofluorescence staining of tissue culture cells suggests that gp 190 occurs exclusively in the nucleus during interphase. This polypeptide becomes dispersed throughout the cell in mitotic prophase when the nuclear envelope is disassembled, and subsequently returns to the nuclear surfaces during telophase when the nuclear envelope is reconstructed. Immunoferritin labeling of Triton-treated rat liver nuclei demonstrates that gp 190 occurs exclusively in the nuclear pore complex, in the regions of the cytoplasmic (and possibly nucleoplasmic) pore complex annuli. A polypeptide that cross-reacts with gp 190 is present in diverse vertebrate species, as shown by antibody labeling of nitrocellulose SDS gel transfers. On the basis of its biochemical characteristics, we suggest that gp 190 may be involved in anchoring the pore complex to nuclear envelope membranes. PMID:7153248
2009-10-23
CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights illuminate the pad and the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
2009-10-23
CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights illuminate the pad and the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
2009-10-23
CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights illuminate the pad and the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
2009-10-23
CAPE CANAVERAL, Fla. - As night settles over Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
2009-10-23
CAPE CANAVERAL, Fla. - As night settles over Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
2009-10-23
CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
2009-10-23
CAPE CANAVERAL, Fla. - As night settles over Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
2009-10-23
CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights illuminate the pad and the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
2009-10-23
CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights illuminate the pad and the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
2009-10-23
CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
2009-10-23
CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
2009-10-23
CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
2009-10-23
CAPE CANAVERAL, Fla. - As night settles over Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
2009-10-23
CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
2009-10-23
CAPE CANAVERAL, Fla. - As night settles over Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
Molecular Characterization of Cryptosporidium spp. in Children from Mexico
Valenzuela, Olivia; González-Díaz, Mariana; Garibay-Escobar, Adriana; Burgara-Estrella, Alexel; Cano, Manuel; Durazo, María; Bernal, Rosa M.; Hernandez, Jesús; Xiao, Lihua
2014-01-01
Cryptosporidiosis is a parasitic disease caused by Cryptosporidium spp. In immunocompetent individuals, it usually causes an acute and self-limited diarrhea; in infants, infection with Cryptosporidium spp. can cause malnutrition and growth retardation, and declined cognitive ability. In this study, we described for the first time the distribution of C. parvum and C. hominis subtypes in 12 children in Mexico by sequence characterization of the 60-kDa glycoprotein (GP60) gene of Cryptosporidium. Altogether, 7 subtypes belonging to 4 subtype families of C. hominis (Ia, Ib, Id and Ie) and 1 subtype family of C. parvum (IIa) were detected, including IaA14R3, IaA15R3, IbA10G2, IdA17, IeA11G3T3, IIaA15G2R1 and IIaA16G1R1. The frequency of the subtype families and subtypes in the samples analyzed in this study differed from what was observed in other countries. PMID:24755606
Molecular characterization of Cryptosporidium spp. in children from Mexico.
Valenzuela, Olivia; González-Díaz, Mariana; Garibay-Escobar, Adriana; Burgara-Estrella, Alexel; Cano, Manuel; Durazo, María; Bernal, Rosa M; Hernandez, Jesús; Xiao, Lihua
2014-01-01
Cryptosporidiosis is a parasitic disease caused by Cryptosporidium spp. In immunocompetent individuals, it usually causes an acute and self-limited diarrhea; in infants, infection with Cryptosporidium spp. can cause malnutrition and growth retardation, and declined cognitive ability. In this study, we described for the first time the distribution of C. parvum and C. hominis subtypes in 12 children in Mexico by sequence characterization of the 60-kDa glycoprotein (GP60) gene of Cryptosporidium. Altogether, 7 subtypes belonging to 4 subtype families of C. hominis (Ia, Ib, Id and Ie) and 1 subtype family of C. parvum (IIa) were detected, including IaA14R3, IaA15R3, IbA10G2, IdA17, IeA11G3T3, IIaA15G2R1 and IIaA16G1R1. The frequency of the subtype families and subtypes in the samples analyzed in this study differed from what was observed in other countries.
Characterization of Symptoms in Irritable Bowel Syndrome with Mixed Bowel Habit Pattern
Su, Andrew; Shih, Wendy; Presson, Angela P.; Chang, Lin
2013-01-01
Background Irritable bowel syndrome (IBS) with mixed bowel habits (IBS-M) is a heterogeneous subtype with varying symptoms of constipation and diarrhea, and has not been well characterized. We aimed to characterize gastrointestinal (GI) and non-GI symptoms in IBS-M patients from a U.S. community, and to compare them with IBS with constipation (IBS-C) and diarrhea (IBS-D). Methods Subjects answering community advertisements and meeting Rome III criteria for IBS completed symptom questionnaires. Key Results Of the initial 289 IBS patients identified, one-third (n=51, 32.5%) who met Rome III criteria for IBS-M endorsed having either loose stools or hard stools due to medication. These patients had more severe symptoms and longer duration of flares compared to the rest of the IBS-M group (p = 0.014, p = 0.005). Excluding IBS-M patients with medication-related extremes in stool form who could not be reclassified by medical history, 247 IBS patients were assessed. IBS-M was the most common (44.1%), followed by IBS-C (27.9%), IBS-D (26.3%), and IBS-U (unsubtyped, 1.6%). IBS-M shared symptoms with both IBS-C and IBS-D (p-value range: <0.001–0.002). IBS-M patients reported most bothersome symptoms more similarly to IBS-D, with the most common being irregular bowel habits (27.5%), bloating (26.6%), and abdominal pain (20.2%). There were no differences in non-GI symptoms between subtypes. Conclusions & Inferences IBS-M is a heterogeneous symptom group and thus requires that subclassification criteria be better defined. Use of laxative/anti-diarrheal medications adds to the diagnostic complexity in a potentially more severe subset of IBS-M and should be assessed for accurate subclassification. PMID:23991913
A Search for New Fuel Components in Explosive Mixtures with Ammonium Nitrate
1981-04-30
i AP-PENIMY A. rol~our Tnd#Ix entrl-s for dyes tested for euatecticmixture form7ation with wnmoniua.i nitrate 12010 C.!. Snivent tR.. d 3...lirainhto. %k ith sodium hydroide itnd sodium ýhlnrate l1r6nner, BP 739 182 o d )r nitrate (GP I1S52q) lh-lftier, Gi’ 3628P 9 (1’. 1, 308) (it) Iaat...K -__ __ __ __ _ R___ __ _ __ LEVEL... 0 Final Report A SEARCH FOR NEW FUEL COMPONENTS IN EXPLOSIVE MIXTURES WITH AMMONIUM NITRATE -m i Dr. Maurice C
Characteristics of alpha-glycerophosphate-evoked H2O2 generation in brain mitochondria.
Tretter, Laszlo; Takacs, Katalin; Hegedus, Vera; Adam-Vizi, Vera
2007-02-01
Characteristics of reactive oxygen species (ROS) production in isolated guinea-pig brain mitochondria respiring on alpha-glycerophosphate (alpha-GP) were investigated and compared with those supported by succinate. Mitochondria established a membrane potential (DeltaPsi(m)) and released H(2)O(2) in parallel with an increase in NAD(P)H fluorescence in the presence of alpha-GP (5-40 mm). H(2)O(2) formation and the increase in NAD(P)H level were inhibited by rotenone, ADP or FCCP, respectively, being consistent with a reverse electron transfer (RET). The residual H(2)O(2) formation in the presence of FCCP was stimulated by myxothiazol in mitochondria supported by alpha-GP, but not by succinate. ROS under these conditions are most likely to be derived from alpha-GP-dehydrogenase. In addition, huge ROS formation could be provoked by antimycin in alpha-GP-supported mitochondria, which was prevented by myxothiazol, pointing to the generation of ROS at the quinol-oxidizing center (Q(o)) site of complex III. FCCP further stimulated the production of ROS to the highest rate that we observed in this study. We suggest that the metabolism of alpha-GP leads to ROS generation primarily by complex I in RET, and in addition a significant ROS formation could be ascribed to alpha-GP-dehydrogenase in mammalian brain mitochondria. ROS generation by alpha-GP at complex III is evident only when this complex is inhibited by antimycin.
Selimović-Dragaš, Mediha; Hasić-Branković, Lajla; Korać, Fehim; Đapo, Nermin; Huseinbegović, Amina; Kobašlija, Sedin; Lekić, Meliha; Hatibović-Kofman, Šahza
2013-01-01
Fluoride release is important characteristic of glass-ionomer cements. Quantity of fluoride ions released from the glass-ionomer cements has major importance in definition of their biological activity. The objectives of this study were to define the quantity of fluoride ions released from the experimental glass-ionomer cements and to define the effect of fluoride ions released from the experimental glass-ionomer cements on their cytotoxicity. Concentrations of the fluoride ions released in the evaluated glass-ionomer cements were measured indirectly, by the fluoride-selective WTW, F500 electrode potential, combined with reference R503/D electrode. Statistical analyses of F-ion concentrations released by all glass-ionomers evaluated at two time points, after 8 and after 24 hours, show statistically higher fluoride releases from RMGICs: Vitrebond, Fuji II LC and Fuji Plus, when compared to conventional glass-ionomer cements: Fuji Triage, Fuji IX GP Fast and Ketac Silver, both after 8 and after 24 hours. Correlation coefficient between concentrations of fluoride ion released by evaluated glass-ionomer cements and cytotoxic response of UMR-106 osteoblast cell-line are relatively high, but do not reach levels of biological significance. Correlation between concentrations of fluoride ion released and cytotoxic response of NIH3T3 mouse fibroblast cell line after 8 hours is high, positive and statistically significant for conventional GICs, Fuji Triage and Fuji IX GP Fast, and RMGIC, Fuji II LC. Statistically significant Correlation coefficient between concentrations of fluoride ion released and cytotoxic response of NIH3T3 cell line after 24 hours is defined for RMGIC Fuji II LC only. PMID:23988173
A comparison of the in vitro cytotoxicity of conventional and resin modified glass ionomer cements
Selimović-Dragaš, Mediha; Huseinbegović, Amina; Kobašlija, Sedin; Hatibović-Kofman, Šahza
2012-01-01
To evaluate cytotoxicity of experimental conventional and resin modified glass-ionomer cements on UMR-106 osteoblast cell cultures and cell cultures of NIH3T3 mouse fibroblasts specimens were prepared for every experimental material and divided into: group 1. Conventional glass-ionomer cements: GC Fuji IX GP Fast, GC Fuji Triage and Ketac Silver; group 2. Resin modified glass-ionomer cements: GC Fuji II LC, GC Fuji Plus and Vitrebond; group 3. Positive control was presented by specimens of composite Vit-l-ecence® and negative control-group 4. was presented by α-minimum essential medium for UMR-106 – osteoblast-like cells and Dulbecco’s Modified Eagle’s Medium for NIH3T3 mouse fibroblast cells. Both cell cultures were exposed to 10% of eluate of each single specimen of each experimental material. Experimental dishes were incubated for 24 h. Cell metabolism was evaluated using methyltetrazolium assay. Kruskal-Wallis test and Tukey-Kramer post hoc test for the materials evaluated on NIH3T3 mouse fibroblast cells, as well as UMR-106 osteoblast-like cells showed significantly more cytotoxicity of RMGICs, predominantly Vitrebond to both GICs and composite-Vit-l-ecence®. The lowest influence on cell’s metabolism on UMR-106 osteoblas-like cells was shown by Ketac Silver and the lowest influence on cell’s metabolism on NIH3T3 mouse fibroblast cells was shown by Fuji IX GP Fast. Statistical evaluation of sensitivity of cell lines UMR-106 osteoblast-like cells and NIH3T3 mouse fibroblast cells, using Mann-Whitney test, showed that NIH3T3 mouse fibroblast cells were more sensitive for the evaluation of cytotoxicity of dental materials. PMID:23198945
ERIC Educational Resources Information Center
Bunnell, Tristan
2011-01-01
The International Baccalaureate[R] (IB) world, known as "the IB World," is doubling in size every five years. The IB has become a complex educational product, but offers high levels of consistency and reliability in terms of delivery and assessment. However, since late 2008, a number of concerns have been raised about the quality and manageability…
Regulation of the serotonin transporter in the pathogenesis of irritable bowel syndrome.
Jin, Duo-Chen; Cao, Hai-Long; Xu, Meng-Que; Wang, Si-Nan; Wang, Yu-Ming; Yan, Fang; Wang, Bang-Mao
2016-09-28
Serotonin (5-HT) and the serotonin transporter (SERT) have earned a tremendous amount of attention regarding the pathogenesis of irritable bowel syndrome (IBS). Considering that enteric 5-HT is responsible for the secretion, motility and perception of the bowel, the involvement of altered enteric 5-HT metabolism in the pathogenesis of IBS has been elucidated. Higher 5-HT availability is commonly associated with depressed SERT mRNA in patients with IBS compared with healthy controls. The expression difference of SERT between IBS patients and healthy controls might suggest that SERT plays an essential role in IBS pathogenesis, and SERT was expected to be a novel therapeutic target for IBS. Progress in this area has begun to illuminate the complex regulatory mechanisms of SERT in the etiology of IBS. In this article, current insights regarding the regulation of SERT in IBS are provided, including aspects of SERT gene polymorphisms, microRNAs, immunity and inflammation, gut microbiota, growth factors, among others. Potential SERT-directed therapies for IBS are also described. The potential regulators of SERT are of clinical importance and are important for better understanding IBS pathophysiology and therapeutic strategies.
Direct interaction of the bacteriophage SPP1 packaging ATPase with the portal protein.
Oliveira, Leonor; Cuervo, Ana; Tavares, Paulo
2010-03-05
DNA packaging in tailed bacteriophages and other viruses requires assembly of a complex molecular machine at a specific vertex of the procapsid. This machine is composed of the portal protein that provides a tunnel for DNA entry, an ATPase that fuels DNA translocation (large terminase subunit), and most frequently, a small terminase subunit. Here we characterized the interaction between the terminase ATPase subunit of bacteriophage SPP1 (gp2) and the procapsid portal vertex. We found, by affinity pulldown assays with purified proteins, that gp2 interacts with the portal protein, gp6, independently of the terminase small subunit gp1, DNA, or ATP. The gp2-procapsid interaction via the portal protein depends on gp2 concentration and requires the presence of divalent cations. Competition experiments showed that isolated gp6 can only inhibit gp2-procapsid interactions and DNA packaging at gp6:procapsid molar ratios above 10-fold. Assays with gp6 carrying mutations in distinct regions of its structure that affect the portal-induced stimulation of ATPase and DNA packaging revealed that none of these mutations impedes gp2-gp6 binding. Our results demonstrate that the SPP1 packaging ATPase binds directly to the portal and that the interaction is stronger with the portal embedded in procapsids. Identification of mutations in gp6 that allow for assembly of the ATPase-portal complex but impair DNA packaging support an intricate cross-talk between the two proteins for activity of the DNA translocation motor.
Merkle, R K; Helland, D E; Welles, J L; Shilatifard, A; Haseltine, W A; Cummings, R D
1991-10-01
The envelope glycoprotein of HIV-I in infected, cultured human T cells is synthesized as a precursor of apparent Mr 160 kDa (gp160) and is cleaved to two glycoproteins, gp120 and gp41, which are the mature envelope glycoproteins in the virus. Neither the temporal and spatial features of glycosylation nor the oligosaccharide processing and proteolytic cleavage of the envelope glycoprotein are well understood. To understand more about these events, we investigated the glycosylation and cleavage of the envelope glycoproteins in the CD4+ human cell line, Molt-3, persistently infected with HIV-I (HTLV IIIB). The carbohydrate analysis of gp160 and gp120 and the behavior of the glycoproteins and glycopeptides derived from them on immobilized lectins demonstrate that both of these glycoproteins contain complex- and high-mannose-type Asn-linked oligosaccharides. In addition, the N-glycanase-resistant oligosaccharides of gp120 were found to contain N-acetyl-galactosamine, a common constituent of Ser/Thr-linked oligosaccharides. Pulse-chase analysis of the conversion of [35S]cysteine-labeled gp160 showed that in Molt-3 cells it takes about 2 h for gp120 to arise with a half-time of conversion of about 5 h. At its earliest detectable occurrence, gp120 was found to contain complex-type Asn-linked oligosaccharides. Taken together, these results indicate that proteolytic cleavage of gp160 to gp120 and gp41 occurs either within the trans-Golgi or in a distal compartment.
A Bipartite Signal Regulates the Faithful Delivery of Apical Domain Marker Podocalyxin/Gp135
Yu, Chun-Ying; Chen, Jen-Yau; Lin, Yu-Yu; Shen, Kuo-Fang; Lin, Wei-Ling; Chien, Chung-Liang; ter Beest, Martin B.A.
2007-01-01
Podocalyxin/Gp135 was recently demonstrated to participate in the formation of a preapical complex to set up initial polarity in MDCK cells, a function presumably depending on the apical targeting of Gp135. We show that correct apical sorting of Gp135 depends on a bipartite signal composed of an extracellular O-glycosylation–rich region and the intracellular PDZ domain–binding motif. The function of this PDZ-binding motif could be substituted with a fusion construct of Gp135 with Ezrin-binding phosphoprotein 50 (EBP50). In accordance with this observation, EBP50 binds to newly synthesized Gp135 at the Golgi apparatus and facilitates oligomerization and sorting of Gp135 into a clustering complex. A defective connection between Gp135 and EBP50 or EBP50 knockdown results in a delayed exit from the detergent-resistant microdomain, failure of oligomerization, and basolateral missorting of Gp135. Furthermore, the basolaterally missorted EBP50-binding defective mutant of Gp135 was rapidly retrieved via a PKC-dependent mechanism. According to these findings, we propose a model by which a highly negative charged transmembrane protein could be packed into an apical sorting platform with the aid of its cytoplasmic partner EBP50. PMID:17332505
Structural Plasticity and Conformational Transitions of HIV Envelope Glycoprotein gp120
Korkut, Anil; Hendrickson, Wayne A.
2012-01-01
HIV envelope glycoproteins undergo large-scale conformational changes as they interact with cellular receptors to cause the fusion of viral and cellular membranes that permits viral entry to infect targeted cells. Conformational dynamics in HIV gp120 are also important in masking conserved receptor epitopes from being detected for effective neutralization by the human immune system. Crystal structures of HIV gp120 and its complexes with receptors and antibody fragments provide high-resolution pictures of selected conformational states accessible to gp120. Here we describe systematic computational analyses of HIV gp120 plasticity in such complexes with CD4 binding fragments, CD4 mimetic proteins, and various antibody fragments. We used three computational approaches: an isotropic elastic network analysis of conformational plasticity, a full atomic normal mode analysis, and simulation of conformational transitions with our coarse-grained virtual atom molecular mechanics (VAMM) potential function. We observe collective sub-domain motions about hinge points that coordinate those motions, correlated local fluctuations at the interfacial cavity formed when gp120 binds to CD4, and concerted changes in structural elements that form at the CD4 interface during large-scale conformational transitions to the CD4-bound state from the deformed states of gp120 in certain antibody complexes. PMID:23300605
Lukito, P; Wong, A; Jing, J; Arthur, J F; Marasco, S F; Murphy, D A; Bergin, P J; Shaw, J A; Collecutt, M; Andrews, R K; Gardiner, E E; Davis, A K
2016-11-01
Essentials Relationship of acquired von Willebrand disease (VWD) and platelet dysfunction is explored. Patients with ventricular assist devices and on extracorporeal membrane oxygenation are investigated. Acquired VWD and platelet receptor shedding is demonstrated in the majority of patients. Loss of platelet adhesion receptors glycoprotein (GP) Ibα and GPVI may increase bleeding risk. Background Ventricular assist devices (VADs) and extracorporeal membrane oxygenation (ECMO) are associated with bleeding that is not fully explained by anticoagulant or antiplatelet use. Exposure of platelets to elevated shear in vitro leads to increased shedding. Objectives To investigate whether loss of platelet receptors occurs in vivo, and the relationship with acquired von Willebrand syndrome (AVWS). Methods Platelet counts, coagulation tests and von Willebrand factor (VWF) analyses were performed on samples from 21 continuous flow VAD (CF-VAD), 20 ECMO, 12 heart failure and seven aortic stenosis patients. Levels of platelet receptors were measured by flow cytometry or ELISA. Results The loss of high molecular weight VWF multimers was observed in 18 of 19 CF-VAD and 14 of 20 ECMO patients, consistent with AVWS. Platelet receptor shedding was demonstrated by elevated soluble glycoprotein (GP) VI levels in plasma and significantly reduced surface GPIbα and GPVI levels in CF-VAD and ECMO patients as compared with healthy donors. Platelet receptor levels were also significantly reduced in heart failure patients. Conclusions These data link AVWS and increased platelet receptor shedding in patients with CF-VADs or ECMO for the first time. Loss of the platelet surface receptors GPIbα and GPVI in heart failure, CF-VAD and ECMO patients may contribute to ablated platelet adhesion/activation, and limit thrombus formation under high/pathologic shear conditions. © 2016 International Society on Thrombosis and Haemostasis.
Leav, Brett A.; Mackay, Malanie R.; Anyanwu, Akudo; O' Connor, Roberta M.; Cevallos, Ana Maria; Kindra, Gurpreet; Rollins, Nigel C.; Bennish, Michael L.; Nelson, Richard G.; Ward, Honorine D.
2002-01-01
Cryptosporidium sp. is a significant cause of diarrheal disease, particularly in human immunodeficiency virus (HIV)-infected patients in developing countries. We recently cloned and sequenced several alleles of the highly polymorphic single-copy Cryptosporidium parvum gene Cpgp40/15. This gene encodes a precursor protein that is proteolytically cleaved to yield mature cell surface glycoproteins gp40 and gp15, which are implicated in zoite attachment to and invasion of enterocytes. The most-striking feature of the Cpgp40/15 alleles and proteins is their unprecedented degree of sequence polymorphism, which is far greater than that observed for any other gene or protein studied in C. parvum to date. In this study we analyzed nucleic acid and amino acid sequence polymorphism at the Cpgp40/15 locus of 20 C. parvum isolates from HIV-infected South African children. Fifteen isolates exhibited one of four previously identified genotype I alleles at the Cpgp40/15 locus (Ia, Ib, Ic, and Id), while five displayed a novel set of polymorphisms that defined a new Cpgp40/15 genotype I allele, designated genotype Ie. Surprisingly, only 15 of these isolates exhibited concordant type I alleles at the thrombospondin-related adhesive protein of Cryptosporidium and Cryptosporidium oocyst wall protein loci, while five isolates (all of which displayed Cpgp40/15 genotype Ic alleles) displayed genotype II alleles at these loci. Furthermore, the last five isolates also manifested chimeric genotype Ic/Ib or Ic/II alleles at the Cpgp40/15 locus, raising the possibility of sexual recombination within and between prototypal parasite genotypes. Lastly, children infected with isolates having genotype Ic alleles were significantly older than those infected with isolates displaying other genotype I alleles. PMID:12065532
DOE Office of Scientific and Technical Information (OSTI.GOV)
Almus, F.E.; Rao, L.V.; Fleck, R.A.
An umbilical vein model was designed in which washed vein segments are filled with a reaction mixture containing factor VIIa, Ca(+)+, and a substrate, either 3H-factor IX or 3H-factor X. The vein wall provides the tissue factor (TF) for factor VIIa/TF complexes that activate the substrates as measured by activation peptide release. The model was developed to study TF induced on venous endothelium in situ. However, unlike previous studies with TF expressed on cultured umbilical vein endothelial cells, factors IX and X were activated without first having to expose the vein wall to a perturbing stimulus. Histologic studies revealed thatmore » washing the vein and mixing the reaction mixture before subsampling had disrupted the endothelium. Immunostaining with anti-TF antibodies revealed no staining of endothelium but intense staining in extensions of Wharton's jelly penetrating fenestrations of the muscularis media of the vein. Thus, the model provided data on factor VIIa/TF formed, not on endothelium, but within the mucoid connective tissue of Wharton's jelly. It is known that factor VIIa/TF formed with TF in suspension or with TF expressed on the surface of cultured cells activates factor X more rapidly than factor IX. In contrast, in the umbilical vein model, when each substrate was present in an 88 nmol/L concentration, factors IX and X were activated at equivalent rates (mean activation rate for factor IX, 18.8 +/- 3.6 nmol/L/h; for factor X, 17.8 +/- 2.9 nmol/L/h; n = 9 paired vein segments). These data strengthen the evidence that factor VIIa/TF activation of factor IX represents a key initial reaction of coagulation in tissues. These results also show that data obtained with factor VIIa/TF complexes formed on the surface of cultured cells need not hold for factor VIIa/TF complexes formed in extracellular matrix.« less
Tokuda, Haruhiko; Kuroyanagi, Gen; Onuma, Takashi; Enomoto, Yukiko; Doi, Tomoaki; Iida, Hiroki; Otsuka, Takanobu; Ogura, Shinji; Iwama, Toru; Kojima, Kumi; Kozawa, Osamu
2018-04-01
It has been previously reported that HSP27 is released from platelets in type 2 diabetes mellitus (DM) patients according to phosphorylation. In the present study, we investigated the effect of ristocetin, a glycoprotein (GP)Ib/IX/V activator, on the release of HSP27 and the effect of anti-platelet agents, such as acetylsalicylic acid (ASA), on this release. Forty-six patients with type 2 DM were recruited, and classified into two groups depending on administration of anti-platelet agents, resulting in 31 patients without these agents (control group) and 15 patients with them (anti-platelet group). Ristocetin potently induced the aggregation of platelets in the two groups. Ristocetin-induced changes of the area under the curve of light transmittance and the ratio of the size of platelet aggregates in the anti-platelet group were slightly different from those in the control group. On the other hand, the levels of phosphorylated-HSP27 induced by ristocetin in the platelets from a patient of the anti-platelet group taking ASA were significantly lower than those from a patient of the control group. The levels of HSP27 release from the ristocetin-stimulated platelets were significantly correlated with the levels of phosphorylated-HSP27 in the platelets from patients in the two groups. The levels of HSP27 release and those of platelet-derived growth factor-AB (PDGF-AB) secretion stimulated by ristocetin in the anti-platelet group were lower than those in the control group. In addition, the levels of HSP27 release and those of PDGF-AB secretion stimulated by ADP in the anti-platelet group were lower than those in the control group. These results strongly suggest that anti-platelet agents inhibit the HSP27 release from platelets stimulated by ristocetin but not the aggregation in type 2 DM patients.
Phenotyping of subjects for large scale studies on patients with IBS.
Boeckxstaens, G E; Drug, V; Dumitrascu, D; Farmer, A D; Hammer, J; Hausken, T; Niesler, B; Pohl, D; Pojskic, L; Polster, A; Simren, M; Goebel-Stengel, M; Van Oudenhove, L; Vassallo, M; Wensaas, K-A; Aziz, Q; Houghton, L A
2016-08-01
Irritable bowel syndrome (IBS) is a complex condition with multiple factors contributing to its aetiology and pathophysiology. Aetiologically these include genetics, life-time events and environment, and physiologically, changes in motility, central processing, visceral sensitivity, immunity, epithelial permeability and gastrointestinal microflora. Such complexity means there is currently no specific reliable biomarker for IBS, and thus IBS continues to be diagnosed and classified according to symptom based criteria, the Rome Criteria. Carefully phenotyping and characterisation of a 'large' pool of IBS patients across Europe and even the world however, might help identify sub-populations with accuracy and consistency. This will not only aid future research but improve tailoring of treatment and health care of IBS patients. The aim of this position paper is to discuss the requirements necessary to standardize the process of selecting and phenotyping IBS patients and how to organise the collection and storage of patient information/samples in such a large multi-centre pan European/global study. We include information on general demographics, gastrointestinal symptom assessment, psychological factors, quality of life, physiological evaluation, genetic/epigenetic and microbiota analysis, biopsy/blood sampling, together with discussion on the organisational, ethical and language issues associated with implementing such a study. The proposed approach and documents selected to be used in such a study was the result of a thoughtful and thorough four-year dialogue amongst experts associated with the European COST action BM1106 GENIEUR (www.GENIEUR.eu). © 2016 John Wiley & Sons Ltd.
Choe, Jong Kwon; Mehnert, Michelle H; Guest, Jeremy S; Strathmann, Timothy J; Werth, Charles J
2013-05-07
Environmental impacts of conventional and emerging perchlorate drinking water treatment technologies were assessed using life cycle assessment (LCA). Comparison of two ion exchange (IX) technologies (i.e., nonselective IX with periodic regeneration using brines and perchlorate-selective IX without regeneration) at an existing plant shows that brine is the dominant contributor for nonselective IX, which shows higher impact than perchlorate-selective IX. Resource consumption during the operational phase comprises >80% of the total impacts. Having identified consumables as the driving force behind environmental impacts, the relative environmental sustainability of IX, biological treatment, and catalytic reduction technologies are compared more generally using consumable inputs. The analysis indicates that the environmental impacts of heterotrophic biological treatment are 2-5 times more sensitive to influent conditions (i.e., nitrate/oxygen concentration) and are 3-14 times higher compared to IX. However, autotrophic biological treatment is most environmentally beneficial among all. Catalytic treatment using carbon-supported Re-Pd has a higher (ca. 4600 times) impact than others, but is within 0.9-30 times the impact of IX with a newly developed ligand-complexed Re-Pd catalyst formulation. This suggests catalytic reduction can be competitive with increased activity. Our assessment shows that while IX is an environmentally competitive, emerging technologies also show great promise from an environmental sustainability perspective.
Pinard, Melissa A.; Aggarwal, Mayank; Mahon, Brian P.; ...
2015-09-23
Human carbonic anhydrase (CA; EC 4.2.1.1) isoform IX (CA IX) is an extracellular zinc metalloenzyme that catalyzes the reversible hydration of CO 2to HCO 3 $-$, thereby playing a role in pH regulation. The majority of normal functioning cells exhibit low-level expression of CA IX. However, in cancer cells CA IX is upregulated as a consequence of a metabolic transition known as the Warburg effect. The upregulation of CA IX for cancer progression has drawn interest in it being a potential therapeutic target. CA IX is a transmembrane protein, and its purification, yield and crystallization have proven challenging to structure-basedmore » drug design, whereas the closely related cytosolic soluble isoform CA II can be expressed and crystallized with ease. Therefore, we have utilized structural alignments and site-directed mutagenesis to engineer a CA II that mimics the active site of CA IX. In this paper, the X-ray crystal structure of this CA IX mimic in complex with sucrose is presented and has been refined to a resolution of 1.5 Å, anR cryst of 18.0% and anR free of 21.2%. Finally, the binding of sucrose at the entrance to the active site of the CA IX mimic, and not CA II, in a non-inhibitory mechanism provides a novel carbohydrate moiety binding site that could be further exploited to design isoform-specific inhibitors of CA IX.« less
Bastepe, Murat; Altug-Teber, Ozge; Agarwal, Chhavi; Oberfield, Sharon E; Bonin, Michael; Jüppner, Harald
2011-03-01
Pseudohypoparathyoridism type Ib (PHP-Ib) typically defines the presence of end-organ resistance to parathyroid hormone in the absence of Albright's hereditary osteodystrophy. Patients affected by this disorder present with imprinting defects in the complex GNAS locus. Microdeletions within STX16 or GNAS have been identified in familial cases with PHP-Ib, but the molecular cause of the GNAS imprinting defects in sporadic PHP-Ib cases remains poorly defined. We now report a case with sporadic PHP-Ib for whom a SNPlex analysis revealed loss of the maternal GNAS allele. Further analysis of the entire genome with a 100K SNP chip identified a paternal uniparental isodisomy affecting the entire chromosome 20 without evidence for another chromosomal abnormality. Our findings explain the observed GNAS methylation changes and the patient's hormone resistance, and furthermore suggest that chromosome 20 harbors, besides GNAS, no additional imprinted region that contributes to the clinical and laboratory phenotype. Copyright © 2010 Elsevier Inc. All rights reserved.
Irritable Bowel Syndrome: Clinical Manifestations, Dietary Influences, and Management
Ikechi, Ronald; Fischer, Bradford D.; DeSipio, Joshua; Phadtare, Sangita
2017-01-01
Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder that is characterized by symptoms of chronic abdominal pain and altered bowel habits in the absence of an overtly identifiable cause. It is the most commonly diagnosed functional gastrointestinal disorder, accounting for about one third of gastroenterology visits. It generally presents as a complex of symptoms, including psychological dysfunction. Hypersensitivity to certain foods, especially foods that contain high amounts of fructose, plays a role in the pathophysiology of IBS. Elevated consumption of high-fructose corn syrup (HFCS) has been discussed in this aspect. The treatment options for IBS are challenging and varied. In addition to dietary restrictions for HFCS-induced IBS, such as low-FODMAP (Fermentable Oligosaccharides, Disaccharide, Monosaccharides, and Polyols) diets, existing drug therapies are administered based on the predominant symptoms and IBS-subtype. Patients with IBS are likely to suffer from issues, such as anxiety, depression, and post-traumatic-stress disorder. Biopsychosocial factors particularly socioeconomic status, sex, and race should, thus, be considered for diagnostic evaluation of patients with IBS. PMID:28445436
Acid Sphingomyelinase Promotes Cellular Internalization of Clostridium perfringens Iota-Toxin.
Nagahama, Masahiro; Takehara, Masaya; Miyamoto, Kazuaki; Ishidoh, Kazumi; Kobayashi, Keiko
2018-05-20
Clostridium perfringens iota-toxin is a binary actin-ADP-ribosylating toxin composed of the enzymatic component Ia and receptor binding component Ib. Ib binds to a cell surface receptor, forms Ib oligomer in lipid rafts, and associates with Ia. The Ia-Ib complex then internalizes by endocytosis. Here, we showed that acid sphingomyelinase (ASMase) facilitates the cellular uptake of iota-toxin. Inhibitions of ASMase and lysosomal exocytosis by respective blockers depressed cell rounding induced by iota-toxin. The cytotoxicity of the toxin increased in the presence of Ca 2+ in extracellular fluids. Ib entered target cells in the presence but not the absence of Ca 2+ . Ib induced the extracellular release of ASMase in the presence of Ca 2+ . ASMase siRNA prevented the cell rounding induced by iota-toxin. Furthermore, treatment of the cells with Ib resulted in the production of ceramide in cytoplasmic vesicles. These observations showed that ASMase promotes the internalization of iota-toxin into target cells.
Acid Sphingomyelinase Promotes Cellular Internalization of Clostridium perfringens Iota-Toxin
Nagahama, Masahiro; Takehara, Masaya; Miyamoto, Kazuaki; Ishidoh, Kazumi; Kobayashi, Keiko
2018-01-01
Clostridium perfringens iota-toxin is a binary actin-ADP-ribosylating toxin composed of the enzymatic component Ia and receptor binding component Ib. Ib binds to a cell surface receptor, forms Ib oligomer in lipid rafts, and associates with Ia. The Ia-Ib complex then internalizes by endocytosis. Here, we showed that acid sphingomyelinase (ASMase) facilitates the cellular uptake of iota-toxin. Inhibitions of ASMase and lysosomal exocytosis by respective blockers depressed cell rounding induced by iota-toxin. The cytotoxicity of the toxin increased in the presence of Ca2+ in extracellular fluids. Ib entered target cells in the presence but not the absence of Ca2+. Ib induced the extracellular release of ASMase in the presence of Ca2+. ASMase siRNA prevented the cell rounding induced by iota-toxin. Furthermore, treatment of the cells with Ib resulted in the production of ceramide in cytoplasmic vesicles. These observations showed that ASMase promotes the internalization of iota-toxin into target cells. PMID:29783772
Lee, Wonbae; Gillies, John P.; Jose, Davis; Israels, Brett A.; von Hippel, Peter H.; Marcus, Andrew H.
2016-01-01
Gene 32 protein (gp32) is the single-stranded (ss) DNA binding protein of the bacteriophage T4. It binds transiently and cooperatively to ssDNA sequences exposed during the DNA replication process and regulates the interactions of the other sub-assemblies of the replication complex during the replication cycle. We here use single-molecule FRET techniques to build on previous thermodynamic studies of gp32 binding to initiate studies of the dynamics of the isolated and cooperative binding of gp32 molecules within the replication complex. DNA primer/template (p/t) constructs are used as models to determine the effects of ssDNA lattice length, gp32 concentration, salt concentration, binding cooperativity and binding polarity at p/t junctions. Hidden Markov models (HMMs) and transition density plots (TDPs) are used to characterize the dynamics of the multi-step assembly pathway of gp32 at p/t junctions of differing polarity, and show that isolated gp32 molecules bind to their ssDNA targets weakly and dissociate quickly, while cooperatively bound dimeric or trimeric clusters of gp32 bind much more tightly, can ‘slide’ on ssDNA sequences, and exhibit binding dynamics that depend on p/t junction polarities. The potential relationships of these binding dynamics to interactions with other components of the T4 DNA replication complex are discussed. PMID:27694621
Statistical Aspects of Ice Gouging on the Alaskan Shelf of the Beaufort Sea,
1983-09-01
ici 1)N I’ao’ ofciv i1111 da t Cl t it:c) dcc iiiiik i onIII ol l % I IIouI ile as~ d a 1c’ iiici of ,ic dcli al\\2 Not1. I % .. ol I lOt ii title...Ccii hilial dclisl to fileicll of a p-ii peline lot a IX1 (X)-. Miid 10-\\Cat McUMr 1crOd .31 .... v STATISTICAL ASPECTS OF ICE GOUGING ON THE ALASKAN...dlata obtained hetceni 19-2 and -l aw etcnatr’’ib (I-). I Ilti, v, ’Icletriiutted 1 9,9 (ele cl iug 1 974) \\ -ere CL Ird in the pr~ mI. a~ctag ing tile
Probiotics and irritable bowel syndrome.
Dai, Cong; Zheng, Chang-Qing; Jiang, Min; Ma, Xiao-Yu; Jiang, Li-Juan
2013-09-28
Irritable bowel syndrome (IBS) is common gastrointestinal problems. It is characterized by abdominal pain or discomfort, and is associated with changes in stool frequency and/or consistency. The etiopathogenesis of IBS may be multifactorial, as is the pathophysiology, which is attributed to alterations in gastrointestinal motility, visceral hypersensitivity, intestinal microbiota, gut epithelium and immune function, dysfunction of the brain-gut axis or certain psychosocial factors. Current therapeutic strategies are often unsatisfactory. There is now increasing evidence linking alterations in the gastrointestinal microbiota and IBS. Probiotics are living organisms which, when ingested in certain numbers, exert health benefits beyond inherent basic nutrition. Probiotics have numerous positive effects in the gastrointestinal tract. Recently, many studies have suggested that probiotics are effective in the treatment of IBS. The mechanisms of probiotics in IBS are very complex. The purpose of this review is to summarize the evidence and mechanisms for the use of probiotics in the treatment of IBS.
Post-traumatic Stress Disorder Is Associated With Irritable Bowel Syndrome in African Americans.
Iorio, Natalya; Makipour, Kian; Palit, Amiya; Friedenberg, Frank K
2014-10-30
Psychosocial stressors likely play an important role in irritable bowel syndrome (IBS). The association between IBS and post-trau-matic stress disorder (PTSD) in non-minorities has been described. Our aim was to investigate the potential association between IBS and PTSD in an urban African American population. Our institution maintains a longitudinal population-based survey of African Americans (AA). The survey utilizes a complex, stratified sampling design. The study group consisted of adult AA meeting Rome III criteria for IBS of any subtype. The 4-item Primary Care PTSD screener was administered; score of≥ 3 (range, 0-4) was considered positive for PTSD. Depression (Public Health Questionnaire-9 depression) and anxiety (generalized anxiety disorder-7) levels were measured using standardized scales. To assess quality of life, norm-based physical and mental component summary scores from the short-form 36 health survey ver-sion 2 were obtained. Descriptive and inferential statistics were calculated using Complex Sample Module of SPSS after weight-ing of the study sample. Four hundred nineteen subjects included corresponded to a weighted 21,264 (95% CI, 19,777-22,751) individuals. The preva-lence of IBS in our sample of urban AA was 8.2%. In multivariate regression analysis, female gender, age > 40, higher educa-tional attainment and divorce were independently associated with IBS. Those with IBS were considerably more likely to suffer from PTSD (OR, 4.54; 95% CI, 4.07-5.06). PTSD was independently associated with depression, anxiety, harmful drinking and substance abuse. In AA, PTSD is independently associated with IBS. PTSD has a significantly negative impact on physical and mental self-assess-ment of quality of life. Evaluation of minorities presenting with functional gastrointestinal disorders should include screening for PTSD.(J Neurogastroenterol Motil 2014;20:523-530).
Insights into Brain Glycogen Metabolism
Mathieu, Cécile; de la Sierra-Gallay, Ines Li; Duval, Romain; Xu, Ximing; Cocaign, Angélique; Léger, Thibaut; Woffendin, Gary; Camadro, Jean-Michel; Etchebest, Catherine; Haouz, Ahmed; Dupret, Jean-Marie; Rodrigues-Lima, Fernando
2016-01-01
Brain glycogen metabolism plays a critical role in major brain functions such as learning or memory consolidation. However, alteration of glycogen metabolism and glycogen accumulation in the brain contributes to neurodegeneration as observed in Lafora disease. Glycogen phosphorylase (GP), a key enzyme in glycogen metabolism, catalyzes the rate-limiting step of glycogen mobilization. Moreover, the allosteric regulation of the three GP isozymes (muscle, liver, and brain) by metabolites and phosphorylation, in response to hormonal signaling, fine-tunes glycogenolysis to fulfill energetic and metabolic requirements. Whereas the structures of muscle and liver GPs have been known for decades, the structure of brain GP (bGP) has remained elusive despite its critical role in brain glycogen metabolism. Here, we report the crystal structure of human bGP in complex with PEG 400 (2.5 Å) and in complex with its allosteric activator AMP (3.4 Å). These structures demonstrate that bGP has a closer structural relationship with muscle GP, which is also activated by AMP, contrary to liver GP, which is not. Importantly, despite the structural similarities between human bGP and the two other mammalian isozymes, the bGP structures reveal molecular features unique to the brain isozyme that provide a deeper understanding of the differences in the activation properties of these allosteric enzymes by the allosteric effector AMP. Overall, our study further supports that the distinct structural and regulatory properties of GP isozymes contribute to the different functions of muscle, liver, and brain glycogen. PMID:27402852
Cardamone, Francesca; Pizzi, Simone; Iacovelli, Federico; Falconi, Mattia; Desideri, Alessandro
2017-01-01
Human topoisomerase IB is an important target in cancer therapy and drugs selectively stabilizing the topoisomerase IB-DNA covalent complex are in clinical use for several cancer types. Tyrosyl- DNA phosphodiesterase 1 is involved in the DNA repair resolving the topoisomerase IB-DNA covalent complex that is extremely dangerous for the survival of the cells since it produces an irreversible DNA damage. Given the close biological relationship between these two enzymes, the development of synergistic inhibitors, called dual-inhibitors, is an important challenge in cancer therapy and computer-aided drug design may help in the identification of the best compounds. In this review, an overview of the compounds inhibiting one of the two enzymes or acting as dual inhibitors is provided. Moreover, the general procedures of the virtual screening approach, providing a description of two widely used opensource programs, namely AutoDock4 and AutoDock Vina, are described. Finally, an application of the two programs on a selected number of dual inhibitors for tyrosyl-DNA phosphodiesterase 1 and topoisomerase IB and their performance is briefly discussed. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Coleman, Stewart; Choi, K Yeon; Root, Matthew; McGregor, Alistair
2016-07-01
In human cytomegalovirus (HCMV), tropism to epithelial and endothelial cells is dependent upon a pentameric complex (PC). Given the structure of the placenta, the PC is potentially an important neutralizing antibody target antigen against congenital infection. The guinea pig is the only small animal model for congenital CMV. Guinea pig cytomegalovirus (GPCMV) potentially encodes a UL128-131 HCMV PC homolog locus (GP128-GP133). In transient expression studies, GPCMV gH and gL glycoproteins interacted with UL128, UL130 and UL131 homolog proteins (designated GP129 and GP131 and GP133 respectively) to form PC or subcomplexes which were determined by immunoprecipitation reactions directed to gH or gL. A natural GP129 C-terminal deletion mutant (aa 107-179) and a chimeric HCMV UL128 C-terminal domain swap GP129 mutant failed to form PC with other components. GPCMV infection of a newly established guinea pig epithelial cell line required a complete PC and a GP129 mutant virus lacked epithelial tropism and was attenuated in the guinea pig for pathogenicity and had a low congenital transmission rate. Individual knockout of GP131 or 133 genes resulted in loss of viral epithelial tropism. A GP128 mutant virus retained epithelial tropism and GP128 was determined not to be a PC component. A series of GPCMV mutants demonstrated that gO was not strictly essential for epithelial infection whereas gB and the PC were essential. Ectopic expression of a GP129 cDNA in a GP129 mutant virus restored epithelial tropism, pathogenicity and congenital infection. Overall, GPCMV forms a PC similar to HCMV which enables evaluation of PC based vaccine strategies in the guinea pig model.
McGregor, Alistair
2016-01-01
In human cytomegalovirus (HCMV), tropism to epithelial and endothelial cells is dependent upon a pentameric complex (PC). Given the structure of the placenta, the PC is potentially an important neutralizing antibody target antigen against congenital infection. The guinea pig is the only small animal model for congenital CMV. Guinea pig cytomegalovirus (GPCMV) potentially encodes a UL128-131 HCMV PC homolog locus (GP128-GP133). In transient expression studies, GPCMV gH and gL glycoproteins interacted with UL128, UL130 and UL131 homolog proteins (designated GP129 and GP131 and GP133 respectively) to form PC or subcomplexes which were determined by immunoprecipitation reactions directed to gH or gL. A natural GP129 C-terminal deletion mutant (aa 107–179) and a chimeric HCMV UL128 C-terminal domain swap GP129 mutant failed to form PC with other components. GPCMV infection of a newly established guinea pig epithelial cell line required a complete PC and a GP129 mutant virus lacked epithelial tropism and was attenuated in the guinea pig for pathogenicity and had a low congenital transmission rate. Individual knockout of GP131 or 133 genes resulted in loss of viral epithelial tropism. A GP128 mutant virus retained epithelial tropism and GP128 was determined not to be a PC component. A series of GPCMV mutants demonstrated that gO was not strictly essential for epithelial infection whereas gB and the PC were essential. Ectopic expression of a GP129 cDNA in a GP129 mutant virus restored epithelial tropism, pathogenicity and congenital infection. Overall, GPCMV forms a PC similar to HCMV which enables evaluation of PC based vaccine strategies in the guinea pig model. PMID:27387220
2008-12-23
glycoprotein precursor (GPC) signal peptide (SP) or human IgG signal sequences (s.s.). GP2 was secreted from cells only when (1) the transmembrane (TM) domain... peptide (SP) or human IgG signal sequences (s.s.). GP2 was secreted from cells only when (1) the transmembrane (TM) domain was deleted, the...terminal signal peptide (SP), which directs the precursor to the endoplasmic retic- ulum (ER) for further processing [11]. The SP, which has been
2008-12-23
glycoprotein precursor (GPC) signal peptide (SP) or human IgG signal sequences (s.s.). GP2 was secreted from cells only when (1) the transmembrane (TM) domain...consistent with viral TM fusion proteins [9,10]. GPC con- tains a 58 residue hydrophobic N-terminal signal peptide (SP), which directs the precursor to the...including GPC, GP1, and GP2. Various signal peptides , purification tags, and modifications to internal domains were employed for the generation and
Riemann, Anne; Güttler, Antje; Haupt, Verena; Wichmann, Henri; Reime, Sarah; Bache, Matthias; Vordermark, Dirk; Thews, Oliver
2018-03-05
Carbonic anhydrase (CA) IX has emerged as a promising target for cancer therapy. It is highly upregulated in hypoxic regions and mediates pH regulation critical for tumor cell survival as well as extracellular acidification of the tumor microenvironment, which promotes tumor aggressiveness via various mechanisms, such as augmenting metastatic potential. Therefore, the aim of this study was to analyze the complex interdependency between CA IX and the tumor microenvironment in prostate tumor cells with regard to potential therapeutic implications. CA IX was upregulated by hypoxia as well as acidosis in prostate cancer cells. This induction did not modulate intracellular pH but led to extracellular acidification. Pharmacological inhibition of CA IX activity by U104 (SLC-0111) resulted in a reduction in tumor cell growth and an increase in apoptotic cell death. Intracellular pH was reduced under normoxic and even more so under hypoxic conditions when CA IX level was high. However, although intracellular pH regulation was disturbed, targeting CA IX in combination with daunorubicin or cisplatin did not intensify apoptotic tumor cell death. Hence, targeting CA IX in prostate cancer cells can lead to intracellular pH dysregulation and, consequently, can reduce cellular growth and elevate apoptotic cell death. Attenuation of extracellular acidification by blocking CA IX might additionally impede tumor progression and metastasis. However, no beneficial effect was seen when targeting CA IX in combination with chemotherapeutic drugs.
van Gerven, Joop; Cohen, Adam
2018-01-30
The first administration of a new compound in humans is an important milestone. A major source of information for the researcher is the investigator's brochure (IB). Such a document, has a size of several hundred pages. The IB should enable investigators or regulators to independently assess the risk-benefit of the proposed trial but the size and complexity makes this difficult. This article offers a practical tool for the integration and subsequent communication of the complex information from the IB or other relevant data sources. This paper is accompanied by an accessible software tool to construct a single page colour-coded overview of preclinical and clinical data. © 2018 The British Pharmacological Society.
Blanco, María A; Montoya, Ana; Iborra, Asunción; Fuentes, Isabel
2014-09-01
Cryptosporidium spp. are enteric parasites that infect humans and animals. In immunocompromised patients infection can be fatal. This study was conducted to identify sub-populations of Cryptosporidium hominis and C. parvum isolates from HIV-seropositive patients in Equatorial Guinea. In a previous study conducted in Equatorial Guinea, faecal samples from 171 HIV patients with gastrointestinal symptoms were analyzed. Of these, 13 and 17 were positive for C. hominis and C. parvum, respectively. The isolates were characterized using gp60 gene analysis. The gp60 gene could only be detected in 57% (17/30) of cases (10 C. parvum and 7 C. hominis). Three C. hominis (Ia, Ib and Id) and two C. parvum (IIc and IIe) subtype families were detected, including several subtypes. The study identified a high diversity of Cryptosporidium subtypes, suggesting that anthroponotic transmission plays an important role in the epidemiology of Cryptosporidium spp. in HIV-seropositive patients in Equatorial Guinea. © The Author 2014. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Llewellyn, Martin S; Messenger, Louisa A; Luquetti, Alejandro O; Garcia, Lineth; Torrico, Faustino; Tavares, Suelene B N; Cheaib, Bachar; Derome, Nicolas; Delepine, Marc; Baulard, Céline; Deleuze, Jean-Francois; Sauer, Sascha; Miles, Michael A
2015-04-01
Chagas disease results from infection with the diploid protozoan parasite Trypanosoma cruzi. T. cruzi is highly genetically diverse, and multiclonal infections in individual hosts are common, but little studied. In this study, we explore T. cruzi infection multiclonality in the context of age, sex and clinical profile among a cohort of chronic patients, as well as paired congenital cases from Cochabamba, Bolivia and Goias, Brazil using amplicon deep sequencing technology. A 450bp fragment of the trypomastigote TcGP63I surface protease gene was amplified and sequenced across 70 chronic and 22 congenital cases on the Illumina MiSeq platform. In addition, a second, mitochondrial target--ND5--was sequenced across the same cohort of cases. Several million reads were generated, and sequencing read depths were normalized within patient cohorts (Goias chronic, n = 43, Goias congenital n = 2, Bolivia chronic, n = 27; Bolivia congenital, n = 20), Among chronic cases, analyses of variance indicated no clear correlation between intra-host sequence diversity and age, sex or symptoms, while principal coordinate analyses showed no clustering by symptoms between patients. Between congenital pairs, we found evidence for the transmission of multiple sequence types from mother to infant, as well as widespread instances of novel genotypes in infants. Finally, non-synonymous to synonymous (dn:ds) nucleotide substitution ratios among sequences of TcGP63Ia and TcGP63Ib subfamilies within each cohort provided powerful evidence of strong diversifying selection at this locus. Our results shed light on the diversity of parasite DTUs within each patient, as well as the extent to which parasite strains pass between mother and foetus in congenital cases. Although we were unable to find any evidence that parasite diversity accumulates with age in our study cohorts, putative diversifying selection within members of the TcGP63I gene family suggests a link between genetic diversity within this gene family and survival in the mammalian host.
2016-01-01
Tolerance and dependence associated with chronic opioid exposure result from molecular, cellular, and neural network adaptations. Such adaptations concern opioid and nonopioid systems, including α2-adrenoceptors (α2-ARs) and I1- and I2-imidazoline binding sites (IBS). Agmatine, one of the hypothesized endogenous ligands of IBS, targeting several systems including α2-ARs and IBS, proved to be able to regulate opioid-induced analgesia and to attenuate the development of tolerance and dependence. Interested in the complex pharmacological profile of agmatine and considering the nature of its targets, we evaluated two series of imidazolines, rationally designed to simultaneously interact with I1-/I2-IBS or I1-/I2-IBS/α2-ARs. The compounds showing the highest affinities for I1-/I2-IBS or I1-/I2-IBS/α2-ARs have been selected for their in vivo evaluation on opiate withdrawal syndrome. Interestingly, 9, displaying I1-/I2-IBS/α2-ARs interaction profile, appears more effective in reducing expression and acquisition of morphine dependence and, therefore, might be considered a promising tool in managing opioid addiction. PMID:27774136
Jose, Davis; Weitzel, Steven E.; Baase, Walter A.; Michael, Miya M.; von Hippel, Peter H.
2015-01-01
We here use our site-specific base analog mapping approach to study the interactions and binding equilibria of cooperatively-bound clusters of the single-stranded DNA binding protein (gp32) of the T4 DNA replication complex with longer ssDNA (and dsDNA) lattices. We show that in cooperatively bound clusters the binding free energy appears to be equi-partitioned between the gp32 monomers of the cluster, so that all bind to the ssDNA lattice with comparable affinity, but also that the outer domains of the gp32 monomers at the ends of the cluster can fluctuate on and off the lattice and that the clusters of gp32 monomers can slide along the ssDNA. We also show that at very low binding densities gp32 monomers bind to the ssDNA lattice at random, but that cooperatively bound gp32 clusters bind preferentially at the 5′-end of the ssDNA lattice. We use these results and the gp32 monomer-binding results of the companion paper to propose a detailed model for how gp32 might bind to and interact with ssDNA lattices in its various binding modes, and also consider how these clusters might interact with other components of the T4 DNA replication complex. PMID:26275774
Luo, Quan; Hiessl, Sebastian; Poehlein, Anja
2013-01-01
Nocardia nova SH22a, a bacterium capable of degrading gutta-percha (GP) and natural rubber (NR), was used to investigate the GP degradation mechanism and the relations between the GP and NR degradation pathways. For this strain, a protocol of electroporation was systematically optimized, and an efficiency of up to 4.3 × 107 CFU per μg of plasmid DNA was achieved. By applying this optimized protocol to N. nova SH22a, a Tn5096-based transposon mutagenesis library of this bacterium was constructed. Among about 12,000 apramycin-resistant transformants, we identified 76 stable mutants defective in GP or NR utilization. Whereas 10 mutants were specifically defective in GP utilization, the growth of the other 66 mutants was affected on both GP and NR. This indicated that the two degradation pathways are quite similar and share many common steps. The larger number of GP-degrading defective mutants could be explained in one of two ways: either (i) the GP pathway is more complex and harbors more specific steps or (ii) the steps for both pathways are almost identical, but in the case of GP degradation there are fewer enzymes involved in each step. The analysis of transposition loci and genetic studies on interesting genes confirmed the crucial role of an α-methylacyl-coenzyme A racemase in the degradation of both GP and NR. We also demonstrated the probable involvement of enzymes participating in oxidoreduction reactions, β-oxidation, and the synthesis of complex cell envelope lipids in the degradation of GP. PMID:23220954
Insights into Brain Glycogen Metabolism: THE STRUCTURE OF HUMAN BRAIN GLYCOGEN PHOSPHORYLASE.
Mathieu, Cécile; Li de la Sierra-Gallay, Ines; Duval, Romain; Xu, Ximing; Cocaign, Angélique; Léger, Thibaut; Woffendin, Gary; Camadro, Jean-Michel; Etchebest, Catherine; Haouz, Ahmed; Dupret, Jean-Marie; Rodrigues-Lima, Fernando
2016-08-26
Brain glycogen metabolism plays a critical role in major brain functions such as learning or memory consolidation. However, alteration of glycogen metabolism and glycogen accumulation in the brain contributes to neurodegeneration as observed in Lafora disease. Glycogen phosphorylase (GP), a key enzyme in glycogen metabolism, catalyzes the rate-limiting step of glycogen mobilization. Moreover, the allosteric regulation of the three GP isozymes (muscle, liver, and brain) by metabolites and phosphorylation, in response to hormonal signaling, fine-tunes glycogenolysis to fulfill energetic and metabolic requirements. Whereas the structures of muscle and liver GPs have been known for decades, the structure of brain GP (bGP) has remained elusive despite its critical role in brain glycogen metabolism. Here, we report the crystal structure of human bGP in complex with PEG 400 (2.5 Å) and in complex with its allosteric activator AMP (3.4 Å). These structures demonstrate that bGP has a closer structural relationship with muscle GP, which is also activated by AMP, contrary to liver GP, which is not. Importantly, despite the structural similarities between human bGP and the two other mammalian isozymes, the bGP structures reveal molecular features unique to the brain isozyme that provide a deeper understanding of the differences in the activation properties of these allosteric enzymes by the allosteric effector AMP. Overall, our study further supports that the distinct structural and regulatory properties of GP isozymes contribute to the different functions of muscle, liver, and brain glycogen. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.
Toremifene interacts with and destabilizes the Ebola virus glycoprotein.
Zhao, Yuguang; Ren, Jingshan; Harlos, Karl; Jones, Daniel M; Zeltina, Antra; Bowden, Thomas A; Padilla-Parra, Sergi; Fry, Elizabeth E; Stuart, David I
2016-07-07
Ebola viruses (EBOVs) are responsible for repeated outbreaks of fatal infections, including the recent deadly epidemic in West Africa. There are currently no approved therapeutic drugs or vaccines for the disease. EBOV has a membrane envelope decorated by trimers of a glycoprotein (GP, cleaved by furin to form GP1 and GP2 subunits), which is solely responsible for host cell attachment, endosomal entry and membrane fusion. GP is thus a primary target for the development of antiviral drugs. Here we report the first, to our knowledge, unliganded structure of EBOV GP, and high-resolution complexes of GP with the anticancer drug toremifene and the painkiller ibuprofen. The high-resolution apo structure gives a more complete and accurate picture of the molecule, and allows conformational changes introduced by antibody and receptor binding to be deciphered. Unexpectedly, both toremifene and ibuprofen bind in a cavity between the attachment (GP1) and fusion (GP2) subunits at the entrance to a large tunnel that links with equivalent tunnels from the other monomers of the trimer at the three-fold axis. Protein–drug interactions with both GP1 and GP2 are predominately hydrophobic. Residues lining the binding site are highly conserved among filoviruses except Marburg virus (MARV), suggesting that MARV may not bind these drugs. Thermal shift assays show up to a 14 °C decrease in the protein melting temperature after toremifene binding, while ibuprofen has only a marginal effect and is a less potent inhibitor. These results suggest that inhibitor binding destabilizes GP and triggers premature release of GP2, thereby preventing fusion between the viral and endosome membranes. Thus, these complex structures reveal the mechanism of inhibition and may guide the development of more powerful anti-EBOV drugs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, W.-J.
2008-05-02
Agglucetin, a platelet glycoprotein (GP)Ib binding protein from Formosan Agkistrodon acutus (A. acutus) venom, could sustain human umbilical vein endothelial cell (HUVEC) proliferation and HUVEC adhering to immobilized agglucetin showed extensive spreading, which was strongly abrogated by integrin antagonists 7E3 and triflavin. Flow cytometric analyses confirmed the expression of GPIb complex on HUVEC is absent and fluorescein isothiocyanate (FITC)-agglucetin binds to HUVEC in a dose-dependent and saturable manner. Furthermore, native agglucetin specifically and dose-dependently inhibited the binding of FITC-23C6, an anti-{alpha}v{beta}3 monoclonal antibody (mAb), but not antibodies against {alpha}2 and {alpha}5, toward HUVEC and purified {alpha}v{beta}3 also bound to immobilizedmore » agglucetin-{beta} in a dose-dependent manner. Moreover, agglucetin exhibited a pro-angiogenic effect in vitro, as well as the focal adhesion kinase (FAK)-associated signaling molecules responsible for HUVEC activation were initiated by agglucetin. In conclusion, agglucetin, acting as a survival factor, promotes endothelial adhesion and angiogenesis by triggering {alpha}v{beta}3 signaling through FAK/phosphatidylinositol 3-kinase (PI3K)/Akt pathway.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sathiyamoorthy, Karthik; Hu, Yao Xiong; Möhl, Britta S.
Herpesvirus entry into host cells is mediated by multiple virally encoded receptor binding and membrane fusion glycoproteins. Despite their importance in host cell tropism and associated disease pathology, the underlying and essential interactions between these viral glycoproteins remain poorly understood. For Epstein–Barr virus (EBV), gHgL/gp42 complexes bind HLA class II to activate membrane fusion with B cells, but gp42 inhibits fusion and entry into epithelial cells. To clarify the mechanism by which gp42 controls the cell specificity of EBV infection, in this paper we determined the structure of gHgL/gp42 complex bound to an anti-gHgL antibody (E1D1). The critical regulator ofmore » EBV tropism is the gp42 N-terminal domain, which tethers the HLA-binding domain to gHgL by wrapping around the exterior of three gH domains. Both the gp42 N-terminal domain and E1D1 selectively inhibit epithelial-cell fusion; however, they engage distinct surfaces of gHgL. Finally, these observations clarify key determinants of EBV host cell tropism.« less
Sathiyamoorthy, Karthik; Hu, Yao Xiong; Möhl, Britta S.; ...
2016-12-08
Herpesvirus entry into host cells is mediated by multiple virally encoded receptor binding and membrane fusion glycoproteins. Despite their importance in host cell tropism and associated disease pathology, the underlying and essential interactions between these viral glycoproteins remain poorly understood. For Epstein–Barr virus (EBV), gHgL/gp42 complexes bind HLA class II to activate membrane fusion with B cells, but gp42 inhibits fusion and entry into epithelial cells. To clarify the mechanism by which gp42 controls the cell specificity of EBV infection, in this paper we determined the structure of gHgL/gp42 complex bound to an anti-gHgL antibody (E1D1). The critical regulator ofmore » EBV tropism is the gp42 N-terminal domain, which tethers the HLA-binding domain to gHgL by wrapping around the exterior of three gH domains. Both the gp42 N-terminal domain and E1D1 selectively inhibit epithelial-cell fusion; however, they engage distinct surfaces of gHgL. Finally, these observations clarify key determinants of EBV host cell tropism.« less
Integrating Experiential Learning and Cases in International Business
ERIC Educational Resources Information Center
Ramburuth, Prem; Daniel, Shirley
2011-01-01
In no other discipline is experiential learning more important than in the complex field of International Business (IB), which aims to prepare students to work and manage across political, economic, national, and sociocultural boundaries. This paper discusses various types of experiential learning activities and approaches to IB teaching, and…
Mathieu, Cécile; Dupret, Jean-Marie; Rodrigues Lima, Fernando
2017-02-01
Glycogen phosphorylase (GP) is the key enzyme that regulates glycogen mobilization in cells. GP is a complex allosteric enzyme that comprises a family of three isozymes: muscle GP (mGP), liver GP (lGP), and brain GP (bGP). Although the three isozymes display high similarity and catalyze the same reaction, they differ in their sensitivity to the allosteric activator adenosine monophosphate (AMP). Moreover, inactivating mutations in mGP and lGP have been known to be associated with glycogen storage diseases (McArdle and Hers disease, respectively). The determination, decades ago, of the structure of mGP and lGP have allowed to better understand the allosteric regulation of these two isoforms and the development of specific inhibitors. Despite its important role in brain glycogen metabolism, the structure of the brain GP had remained elusive. Here, we provide an overview of the human brain GP structure and its relationship with the two other members of this key family of the metabolic enzymes. We also summarize how this structure provides valuable information to understand the regulation of bGP and to design specific ligands of potential pharmacological interest. © 2016 Federation of European Biochemical Societies.
Immunomodulation of enteric neural function in irritable bowel syndrome.
O'Malley, Dervla
2015-06-28
Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder which is characterised by symptoms such as bloating, altered bowel habit and visceral pain. It's generally accepted that miscommunication between the brain and gut underlies the changes in motility, absorpto-secretory function and pain sensitivity associated with IBS. However, partly due to the lack of disease-defining biomarkers, understanding the aetiology of this complex and multifactorial disease remains elusive. Anecdotally, IBS patients have noted that periods of stress can result in symptom flares and many patients exhibit co-morbid stress-related mood disorders such as anxiety and depression. However, in addition to psychosocial stressors, infection-related stress has also been linked with the initiation, persistence and severity of symptom flares. Indeed, prior gastrointestinal infection is one of the strongest predictors of developing IBS. Despite a lack of overt morphological inflammation, the importance of immune factors in the pathophysiology of IBS is gaining acceptance. Subtle changes in the numbers of mucosal immune cell infiltrates and elevated levels of circulating pro-inflammatory cytokines have been reproducibly demonstrated in IBS populations. Moreover, these immune mediators directly affect neural signalling. An exciting new area of research is the role of luminal microbiota in the modulation of neuro-immune signalling, resulting in local changes in gastrointestinal function and alterations in central neural functioning. Progress in this area has begun to unravel some of the complexities of neuroimmune and neuroendocrine interactions and how these molecular exchanges contribute to GI dysfunction.
Kapeller, Johannes; Houghton, Lesley A; Mönnikes, Hubert; Walstab, Jutta; Möller, Dorothee; Bönisch, Heinz; Burwinkel, Barbara; Autschbach, Frank; Funke, Benjamin; Lasitschka, Felix; Gassler, Nikolaus; Fischer, Christine; Whorwell, Peter J; Atkinson, Wendy; Fell, Catherine; Büchner, Karl J; Schmidtmann, Marco; van der Voort, Ivo; Wisser, Anna-Sophia; Berg, Thomas; Rappold, Gudrun; Niesler, Beate
2008-10-01
Diarrhea predominant irritable bowel syndrome (IBS-D) is a complex disorder related to dysfunctions in the serotonergic system. As cis-regulatory variants can play a role in the etiology of complex conditions, we investigated the untranslated regions (UTRs) of the serotonin receptor type 3 subunit genes HTR3A and HTR3E. Mutation analysis was carried out in a pilot sample of 200 IBS patients and 100 healthy controls from the UK. The novel HTR3E 3'-UTR variant c.*76G>A (rs62625044) was associated with female IBS-D (P = 0.033, OR = 8.53). This association was confirmed in a replication study, including 119 IBS-D patients and 195 controls from Germany (P = 0.0046, OR = 4.92). Pooled analysis resulted in a highly significant association of c.*76G>A with female IBS-D (P = 0.0002, OR = 5.39). In a reporter assay, c.*76G>A affected binding of miR-510 to the HTR3E 3'-UTR and caused elevated luciferase expression. HTR3E and miR-510 co-localize in enterocytes of the gut epithelium as shown by in situ hybridization and RT-PCR. This is the first example indicating micro RNA-related expression regulation of a serotonin receptor gene with a cis-regulatory variant affecting this regulation and appearing to be associated with female IBS-D.
Saha, Sourav; Mukherjee, Tulika; Chowdhury, Sayan; Mishra, Amartya; Chowdhury, Somenath Roy; Jaisankar, Parasuraman; Mukhopadhyay, Sibabrata; Majumder, Hemanta K
2013-12-15
Lignans are diphenyl propanoids with vast range of biological activities. The present study provides an important insight into the anti-leishmanial activities of two lignan glycosides, viz. lyoniside and saracoside. These compounds inhibit catalytic activities of topoisomerase IB (LdTopIB) of Leishmania donovani in non-competitive manner and stabilize the LdTopIB mediated cleavage complex formation both in vitro and in Leishmania promastigotes and subsequently inhibit the religation of cleaved strand. These two compounds not only poison LdTopIB but also can interact with the free enzyme LdTopIB. We have also shown that lyoniside and saracoside are cytotoxic to promastigotes and intracellular amastigotes. The protein-DNA complex formation leads to double strand breaks in DNA which ultimately triggers apoptosis-like cell death in the parasite. Along with their cytotoxicity towards sodium antimony gluconate (SAG) sensitive AG83 strain, their ability to kill SAG resistant GE1 strain makes these two compounds potential anti-leishmanial candidates. Not only they effectively kill L. donovani amastigotes inside macrophages in vitro, lyoniside and saracoside demonstrated strong anti-leishmanial efficacies in BALB/c mice model of leishmaniasis. Treatment with these lignan glycosides produce nitric oxide and reactive oxygen species which result in almost complete clearance of the liver and splenic parasite burden. These compounds do not inhibit human topoisomerase IB upto 200μM concentrations and had poor cytotoxic effect on uninfected cultured murine peritoneal macrophages upto 100μM concentrations. Taken together it can be concluded that these compounds can be developed into excellent therapeutic agent against deadly disease leishmaniasis. Copyright © 2013 Elsevier Inc. All rights reserved.
Inclusion bodies as potential vehicles for recombinant protein delivery into epithelial cells
2012-01-01
Background We present the potential of inclusion bodies (IBs) as a protein delivery method for polymeric filamentous proteins. We used as cell factory a strain of E. coli, a conventional host organism, and keratin 14 (K14) as an example of a complex protein. Keratins build the intermediate filament cytoskeleton of all epithelial cells. In order to build filaments, monomeric K14 needs first to dimerize with its binding partner (keratin 5, K5), which is then followed by heterodimer assembly into filaments. Results K14 IBs were electroporated into SW13 cells grown in culture together with a “reporter” plasmid containing EYFP labeled keratin 5 (K5) cDNA. As SW13 cells do not normally express keratins, and keratin filaments are built exclusively of keratin heterodimers (i.e. K5/K14), the short filamentous structures we obtained in this study can only be the result of: a) if both IBs and plasmid DNA are transfected simultaneously into the cell(s); b) once inside the cells, K14 protein is being released from IBs; c) released K14 is functional, able to form heterodimers with EYFP-K5. Conclusions Soluble IBs may be also developed for complex cytoskeletal proteins and used as nanoparticles for their delivery into epithelial cells. PMID:22624805
Pseudohypoparathyroidism type Ib associated with novel duplications in the GNAS locus.
Perez-Nanclares, Gustavo; Velayos, Teresa; Vela, Amaya; Muñoz-Torres, Manuel; Castaño, Luis
2015-01-01
Pseudohypoparathyroidism type 1b (PHP-Ib) is characterized by renal resistance to PTH (and, sometimes, a mild resistance to TSH) and absence of any features of Albright's hereditary osteodystrophy. Patients with PHP-Ib suffer of defects in the methylation pattern of the complex GNAS locus. PHP-Ib can be either sporadic or inherited in an autosomal dominant pattern. Whereas familial PHP-Ib is well characterized at the molecular level, the genetic cause of sporadic PHP-Ib cases remains elusive, although some molecular mechanisms have been associated with this subtype. The aim of the study was to investigate the molecular and imprinting defects in the GNAS locus in two unrelated patients with PHP-Ib. We have analyzed the GNAS locus by direct sequencing, Methylation-Specific Multiplex Ligation-dependent Probe Amplification, microsatellites, Quantitative Multiplex PCR of Short Fluorescent fragments and array-Comparative Genomic Hybridization studies in order to characterize two unrelated families with clinical features of PHP-Ib. We identified two duplications in the GNAS region in two patients with PHP-Ib: one of them, comprising ∼ 320 kb, occurred 'de novo' in the patient, whereas the other one, of ∼ 179 kb in length, was inherited from the maternal allele. In both cases, no other known genetic cause was observed. In this article, we describe the to-our-knowledge biggest duplications reported so far in the GNAS region. Both are associated to PHP-Ib, one of them occurring 'de novo' and the other one being maternally inherited.
Specificity of interactions among the DNA-packaging machine components of T4-related bacteriophages.
Gao, Song; Rao, Venigalla B
2011-02-04
Tailed bacteriophages use powerful molecular motors to package the viral genome into a preformed capsid. Packaging at a rate of up to ∼2000 bp/s and generating a power density twice that of an automobile engine, the phage T4 motor is the fastest and most powerful reported to date. Central to DNA packaging are dynamic interactions among the packaging components, capsid (gp23), portal (gp20), motor (gp17, large "terminase"), and regulator (gp16, small terminase), leading to precise orchestration of the packaging process, but the mechanisms are poorly understood. Here we analyzed the interactions between small and large terminases of T4-related phages. Our results show that the gp17 packaging ATPase is maximally stimulated by homologous, but not heterologous, gp16. Multiple interaction sites are identified in both gp16 and gp17. The specificity determinants in gp16 are clustered in the diverged N- and C-terminal domains (regions I-III). Swapping of diverged region(s), such as replacing C-terminal RB49 region III with that of T4, switched ATPase stimulation specificity. Two specificity regions, amino acids 37-52 and 290-315, are identified in or near the gp17-ATPase "transmission" subdomain II. gp16 binding at these sites might cause a conformational change positioning the ATPase-coupling residues into the catalytic pocket, triggering ATP hydrolysis. These results lead to a model in which multiple weak interactions between motor and regulator allow dynamic assembly and disassembly of various packaging complexes, depending on the functional state of the packaging machine. This might be a general mechanism for regulation of the phage packaging machine and other complex molecular machines.
Solubility of (+/-)-ibuprofen and S (+)-ibuprofen in the presence of cosolvents and cyclodextrins.
Nerurkar, Jayanti; Beach, J W; Park, M O; Jun, H W
2005-01-01
Aqueous solubility is an important parameter for the development of liquid formulations and in the determination of bioavailability of oral dosage forms. Ibuprofen (IB), a nonsteroidal anti-inflammatory drug, is a chiral molecule and is currently used clinically as a racemate (racIB). However, the S form of ibuprofen or S(+)-ibuprofen (SIB) is the biologically active isomer and is primarily responsible for the antiinflammatory activity. Phase solubility studies were carried out to compare the saturation solubilities of racIB and SIB in the presence of common pharmaceutical solvents such as glycerol, sorbitol solution, propylene glycol (PG), and polyethylene glycol (PEG 300) over the range of 20% to 80% v/v in aqueous based systems. The solubilities of the two compounds were also compared in the presence of cyclodextrins such as beta cyclodextrin (CD), hydroxypropyl beta cyclodextrin (HPCD), and beta cyclodextrin sulfobutyl ether sodium salt (CDSB) over the range of 5% to 25% w/v. Solubility determinations were carried at 25 degrees C and 37 degrees C. Cosolvents exponentially increased the solubility of both SIB and racIB, especially in the presence of PG and PEG 300. Glycerol was not very effective in increasing the aqueous solubilities of both compounds, whereas sorbitol solution had a minimal effect on their solubility. PG and PEG 300 increased the solubility of SIB by 400-fold and 1500-fold, respectively, whereas the rise in solubility for racIB was 193-fold and 700-fold, respectively, at 25 degrees C for the highest concentration of the cosolvents used (80% v/v). Of the two compounds studied, higher equilibrium solubilities were observed for SIB as compared with racIB. The derivatized cyclodextrins increased the aqueous solubility of racIB and SIB in a concentration-dependent manner giving AL type of phase diagrams. The phase solubility diagrams indicated the formation of soluble inclusion complexes between the drugs and HPCD and CDSB, which was of 1:1 stoichiometry. The addition of underivatized CD reduced the solubility of racIB and SIB via the formation of an insoluble complex. The S form formed more stable complexes with HPCD and CDSB as compared with raclB. The solubilization process is discussed in terms of solvent polarity and differential solid-state structure of raclB and SIB. The thermodynamic parameters for the solubilization process are presented.
Saha, Sourav; Acharya, Chiranjit; Pal, Uttam; Chowdhury, Somenath Roy; Sarkar, Kahini; Maiti, Nakul C.
2016-01-01
Visceral leishmaniasis is a fatal parasitic disease, and there is an emergent need for development of effective drugs against this neglected tropical disease. We report here the development of a novel spirooxindole derivative, N-benzyl-2,2′α-3,3′,5′,6′,7′,7α,α′-octahydro-2methoxycarbonyl-spiro[indole-3,3′-pyrrolizidine]-2-one (compound 4c), which inhibits Leishmania donovani topoisomerase IB (LdTopIB) and kills the wild type as well as drug-resistant parasite strains. This compound inhibits catalytic activity of LdTopIB in a competitive manner. Unlike camptothecin (CPT), the compound does not stabilize the DNA-topoisomerase IB cleavage complex; rather, it hinders drug-DNA-enzyme covalent complex formation. Fluorescence studies show that the stoichiometry of this compound binding to LdTopIB is 2:1 (mole/mole), with a dissociation constant of 6.65 μM. Molecular docking with LdTopIB using the stereoisomers of compound 4c produced two probable hits for the binding site, one in the small subunit and the other in the hinge region of the large subunit of LdTopIB. This spirooxindole is highly cytotoxic to promastigotes of L. donovani and also induces apoptosis-like cell death in the parasite. Treatment with compound 4c causes depolarization of mitochondrial membrane potential, formation of reactive oxygen species inside parasites, and ultimately fragmentation of nuclear DNA. Compound 4c also effectively clears amastigote forms of wild-type and drug-resistant parasites from infected mouse peritoneal macrophages but has less of an effect on host macrophages. Moreover, compound 4c showed strong antileishmanial efficacies in the BALB/c mouse model of leishmaniasis. This compound potentially can be used as a lead for developing excellent antileishmanial agents against emerging drug-resistant strains of the parasite. PMID:27503653
Characterization and standardization of tissue-simulating protoporphyrin IX optical phantoms
NASA Astrophysics Data System (ADS)
Marois, Mikael; Bravo, Jaime; Davis, Scott C.; Kanick, Stephen Chad
2016-03-01
Optical devices for measuring protoporphryin IX (PpIX) fluorescence in tissue are routinely validated by measurements in optical phantoms. Yet there exists limited data to form a consensus on the recipe for phantoms that both mimic the optical properties found in tissue and yield a reliable and stable relationship between PpIX concentration and the fluorescence remission intensity. This study characterizes the influence of multiple phantom components on PpIX fluorescence emission intensity, using Intralipid as the scattering source, bovine whole blood as the background absorber, and Tween as a surfactant to prevent PpIX aggregation. Optical measurements showed a linear proportionality (r>0.99) between fluorescence intensity and PpIX concentration (0.1 to 10 μg/mL) over a range of Intralipid (1 to 2%) and whole blood (0.5 to 3%) for phantoms containing low surfactant (≤0.1%), with fluorescence intensities and scattering and absorption properties stable for 5 h after mixing. The role of surfactant in PpIX phantoms was found to be complex, as aggregation was evident in aqueous nonturbid phantoms with no surfactant (0% Tween), and avoided in phantoms containing Intralipid as the scattering source with no additional or low amounts of added surfactant (≤0.1% Tween). Conversely, phantoms containing higher surfactant content (>0.1% Tween) and whole blood showed interactions that distorted the fluorescence emissions.
Novel and unexpected clearance mechanisms for cold platelets
Rumjantseva, Viktoria; Hoffmeister, Karin M.
2015-01-01
Storage at room temperature is limited to 5 days because of the risk of bacterial growth and loss of platelet functionality. Platelet refrigeration remains impossible, because once chilled, platelets are rapidly removed from circulation. Chilling platelets (<4 h) clusters glycoprotein (GP) Ibα receptors, and β2 integrins on hepatic macrophages recognize clustered βGlcNAc residues leading to rapid clearance of acutely chilled platelets. Prolonged refrigeration increases the exposure of galactose residues such that, unexpectedly, hepatocytes remove platelets using their asialoglycoprotein receptors. Here we review current knowledge of the mechanisms of platelet removal, the existing knowledge of refrigerated platelet function, and methods to preserve platelet concentrates long-term for transfusion. PMID:19932055
Dual roles for hepatic lectin receptors in the clearance of chilled platelets
Rumjantseva, Viktoria; Grewal, Prabhjit K.; Wandall, Hans H.; Josefsson, Emma C.; Sørensen, Anne Louise; Larson, Göran; Marth, Jamey D.; Hartwig, John H.; Hoffmeister, Karin M.
2015-01-01
Chilling rapidly (<4 h) clusters Glycoprotein - (GP)Ib receptors on blood platelets, and ß2-integrins of hepatic macrophages bind ßGlcNAc residues in the clusters leading to rapid clearance of acutely chilled platelets following transfusion. Although capping the ßGlcNAc moieties by galactosylation prevents clearance, this strategy is ineffective after prolonged (>24 h) refrigeration. We report here that prolonged refrigeration increases the density/concentration of exposed galactose residues such that hepatocytes become increasingly involved in the removal of platelets using their Ashwell-Morell receptors. Macrophages always rapidly remove a large fraction of transfused platelets (~40%). With platelet cooling, hepatocyte-dependent clearance further diminishes their recoveries following transfusion. PMID:19783995
TssA forms a gp6-like ring attached to the type VI secretion sheath.
Planamente, Sara; Salih, Osman; Manoli, Eleni; Albesa-Jové, David; Freemont, Paul S; Filloux, Alain
2016-08-01
The type VI secretion system (T6SS) is a supra-molecular bacterial complex that resembles phage tails. It is a killing machine which fires toxins into target cells upon contraction of its TssBC sheath. Here, we show that TssA1 is a T6SS component forming dodecameric ring structures whose dimensions match those of the TssBC sheath and which can accommodate the inner Hcp tube. The TssA1 ring complex binds the T6SS sheath and impacts its behaviour in vivo In the phage, the first disc of the gp18 sheath sits on a baseplate wherein gp6 is a dodecameric ring. We found remarkable sequence and structural similarities between TssA1 and gp6 C-termini, and propose that TssA1 could be a baseplate component of the T6SS Furthermore, we identified similarities between TssK1 and gp8, the former interacting with TssA1 while the latter is found in the outer radius of the gp6 ring. These observations, combined with similarities between TssF and gp6N-terminus or TssG and gp53, lead us to propose a comparative model between the phage baseplate and the T6SS. © 2016 The Authors. Published under the terms of the CC BY 4.0 license.
Brachvogel, Bent; Zaucke, Frank; Dave, Keyur; Norris, Emma L.; Stermann, Jacek; Dayakli, Münire; Koch, Manuel; Gorman, Jeffrey J.; Bateman, John F.; Wilson, Richard
2013-01-01
The cartilage extracellular matrix is essential for endochondral bone development and joint function. In addition to the major aggrecan/collagen II framework, the interacting complex of collagen IX, matrilin-3, and cartilage oligomeric matrix protein (COMP) is essential for cartilage matrix stability, as mutations in Col9a1, Col9a2, Col9a3, Comp, and Matn3 genes cause multiple epiphyseal dysplasia, in which patients develop early onset osteoarthritis. In mice, collagen IX ablation results in severely disturbed growth plate organization, hypocellular regions, and abnormal chondrocyte shape. This abnormal differentiation is likely to involve altered cell-matrix interactions but the mechanism is not known. To investigate the molecular basis of the collagen IX null phenotype we analyzed global differences in protein abundance between wild-type and knock-out femoral head cartilage by capillary HPLC tandem mass spectrometry. We identified 297 proteins in 3-day cartilage and 397 proteins in 21-day cartilage. Components that were differentially abundant between wild-type and collagen IX-deficient cartilage included 15 extracellular matrix proteins. Collagen IX ablation was associated with dramatically reduced COMP and matrilin-3, consistent with known interactions. Matrilin-1, matrilin-4, epiphycan, and thrombospondin-4 levels were reduced in collagen IX null cartilage, providing the first in vivo evidence for these proteins belonging to the collagen IX interactome. Thrombospondin-4 expression was reduced at the mRNA level, whereas matrilin-4 was verified as a novel collagen IX-binding protein. Furthermore, changes in TGFβ-induced protein βig-h3 and fibronectin abundance were found in the collagen IX knock-out but not associated with COMP ablation, indicating specific involvement in the abnormal collagen IX null cartilage. In addition, the more widespread expression of collagen XII in the collagen IX-deficient cartilage suggests an attempted compensatory response to the absence of collagen IX. Our differential proteomic analysis of cartilage is a novel approach to identify candidate matrix protein interactions in vivo, underpinning further analysis of mutant cartilage lacking other matrix components or harboring disease-causing mutations. PMID:23530037
Designing Curriculum for Real-World International Business Needs
ERIC Educational Resources Information Center
Wolf, Bernard M.; Wright, Lorna
2014-01-01
Economies continue to become more integrated through international trade and foreign investment, as well as by more, and more, complex global supply changes. With the expansion in the level and scope of international business (IB), it becomes all the more important that university graduates seeking careers in IB be able to "successfully hit…
[Synthesis of exo-β-glucosaminidase BY FUNGUS Penicillium sp. IB-37-2].
Aktuganov, G E; Galimzyanova, N F; Teregulova, G A; Melentjev, A I
2016-01-01
A new strain Penicillium sp. IB-37-2, which actively hydrolyzes chitosan (SD ∼80–85%) but possesses low activity against colloidal chitin, was isolated. The fungus was observed to have a high level chitosanase biosynthesis (1.5–3.0 U/mL) during submerged cultivation at 28°C, with a pH of 3.5–7.0 and 220 rpm in nutrient media containing chitosan or chitin from shells of crabs. Purification of the chitosanase enzyme complex from Penicillium sp. IB-37-2 by ultrafiltration and hydrophobic chromatography, followed by denaturing electrophoresis, revealed two predominant proteins with molecular weights of 89 and 41 kDa. The purified enzyme complex demonstrated maximal activity (maximal rate of hydrolysis of dissolved chitosan) and stability at 50–55°C and a pH of 3.5–4.0. The enzyme preparation also hydrolyzed laminarin, β-(1,3)-(1,4)-glycan, and colloidal chitin. Exohydrolysis of chitosan by the preparation isolated from Penicillium sp. IB-37-2 resulted in the formation of single product, D-glucosamine.
In vitro fatigue resistance of glass ionomer cements used in post-and-core applications.
Gateau, P; Sabek, M; Dailey, B
2001-08-01
New glass ionomer cements exhibit better mechanical properties than their older counterparts. However, there is concern about their use as a core material in post-and-core applications. This in vitro study evaluated the fatigue resistance of 2 new glass ionomer cements, Shofu Hi-Dense and Fuji IX GP, and compared their mechanical behavior as a core material under masticatory load with a silver-reinforced glass ionomer (ESPE Ketac-Silver) and a silver amalgam (Cavex Avaloy LC). A total of 100 commercial plastic teeth were divided into 4 groups of 25 specimens each. Titanium posts were placed in the prepared root canals, and cores were built up in amalgam, silver-reinforced glass ionomer cement, and the 2 new glass ionomer cements. The post-and-core specimens were prepared for full cast metal crowns, which were fabricated and cemented with glass ionomer cement. Twenty specimens from each group were placed in a mastication simulator and cyclically loaded with a 400 N force for 1.5 million cycles. The 5 remaining specimens were used as controls. The specimens were sectioned and observed macroscopically and microscopically to determine the number of defects (alterations) in each material. Observed defects were verified with the Kruskal-Wallis test, and the 4 core materials were ranked with the Tukey multiple comparisons test. The mean rank sum values of the defects were as follows: Cavex Avaloy LC Amalgam (16.75), Fuji IX GP (38.50), Shofu Hi-Dense (39.53), and ESPE Ketac-Silver (67.22). The amalgam alloy was significantly different (P< .05) from the others. Under the conditions of this study, the 2 new glass ionomer cements used as core materials showed a higher number of defects than amalgam. These results suggest that their fatigue resistance may be inadequate for post-and-core applications.
Distribution of Cryptosporidium subtypes in humans and domestic and wild ruminants in Portugal.
Alves, Margarida; Xiao, Lihua; Antunes, Francisco; Matos, Olga
2006-08-01
To investigate the transmission of cryptosporidiosis in Portugal, Cryptosporidium hominis and Cryptosporidium parvum from HIV-infected patients, cattle, and wild ruminants were characterized by sequence analysis of the 60-kDa glycoprotein (GP60) gene. Fourteen subtypes within nine subtype families were identified, and three of the subtype families (If, IIb, and IId) were restricted or largely limited to Portugal. Parasites from cattle from various regions in Portugal and wild ruminants in Lisbon showed limited genetic heterogeneity (only two subtype families). All wild ruminants had the same subtype, which was also the predominant subtype in cattle all over Portugal and was found in nine HIV-infected patients in Lisbon. Two other C. parvum subtypes were only restricted to limited locations. In contrast, human parasites displayed 13 subtypes in nine subtype families, with most of the infections caused by parasites in Ib, IIa, IIc, and IId families. Two of the C. parvum subtype families (IIc and IIb) had only been found in humans. The high overall parasite diversity and high percentage of C. hominis infections attributable to Ib and C. parvum infections to IId represent unique characteristics of Cryptosporidium transmission in humans in Portugal.
Sâmia, Luciana B P; Parrilha, Gabrieli L; Da Silva, Jeferson G; Ramos, Jonas P; Souza-Fagundes, Elaine M; Castelli, Silvia; Vutey, Venn; Desideri, Alessandro; Beraldo, Heloisa
2016-06-01
Complexes [Au(PyCT4BrPh)Cl]Cl (1), [Pt(PyCT4BrPh)Cl]0.5KCl (2), and [Pd(PyCT4BrPh)Cl]KCl (3) were obtained with 3-(4-bromophenyl)-1-pyridin-2-ylprop-2-en-1-one thiosemicarbazone (HPyCT4BrPh). Although complexes (2) and (3) did not exhibit potent cytotoxic activity, HPyCT4BrPh and its gold(III) complex (1) proved to be highly cytotoxic against HL-60 (human promyelocytic leukemia) and THP-1 (human monocytic leukemia) cells, and against MDA-MB 231 and MCF-7 (human breast adenocarcinoma) solid tumor cells. Except for HL-60 cells, upon coordination to gold(III) a 2- to 3-fold increase in the cytotoxic effect was observed. An investigation on the possible biological targets of the gold(III) complex was carried out. Complex (1) but not the free thiosemicarbazone inhibits the enzymatic activity of thioredoxin reductase (TrxR). The affinity of 1 for TrxR suggests metal binding to a selenol residue in the active site of the enzyme. While HPyCT4BrPh was inactive, 1 was able to inhibit topoisomerase IB (Topo IB) activity. Hence, inhibition of TrxR and Topo IB could contribute to the mechanism of cytotoxic action of complex (1).
Atzei, A; Luchetti, R; Garagnani, L
2017-05-01
The classical definition of 'Palmer Type IB' triangular fibrocartilage complex tear, includes a spectrum of clinical conditions. This review highlights the clinical and arthroscopic criteria that enable us to categorize five classes on a treatment-oriented classification system of triangular fibrocartilage complex peripheral tears. Class 1 lesions represent isolated tears of the distal triangular fibrocartilage complex without distal radio-ulnar joint instability and are amenable to arthroscopic suture. Class 2 tears include rupture of both the distal triangular fibrocartilage complex and proximal attachments of the triangular fibrocartilage complex to the fovea. Class 3 tears constitute isolated ruptures of the proximal attachment of the triangular fibrocartilage complex to the fovea; they are not visible at radio-carpal arthroscopy. Both Class 2 and Class 3 tears are diagnosed with a positive hook test and are typically associated with distal radio-ulnar joint instability. If required, treatment is through reattachment of the distal radio-ulnar ligament insertions to the fovea. Class 4 lesions are irreparable tears due to the size of the defect or to poor tissue quality and, if required, treatment is through distal radio-ulnar ligament reconstruction with tendon graft. Class 5 tears are associated with distal radio-ulnar joint arthritis and can only be treated with salvage procedures. This subdivision of type IB triangular fibrocartilage complex tear provides more insights in the pathomechanics and treatment strategies. II.
Brachvogel, Bent; Zaucke, Frank; Dave, Keyur; Norris, Emma L; Stermann, Jacek; Dayakli, Münire; Koch, Manuel; Gorman, Jeffrey J; Bateman, John F; Wilson, Richard
2013-05-10
Collagen IX is an integral cartilage extracellular matrix component important in skeletal development and joint function. Proteomic analysis and validation studies revealed novel alterations in collagen IX null cartilage. Matrilin-4, collagen XII, thrombospondin-4, fibronectin, βig-h3, and epiphycan are components of the in vivo collagen IX interactome. We applied a proteomics approach to advance our understanding of collagen IX ablation in cartilage. The cartilage extracellular matrix is essential for endochondral bone development and joint function. In addition to the major aggrecan/collagen II framework, the interacting complex of collagen IX, matrilin-3, and cartilage oligomeric matrix protein (COMP) is essential for cartilage matrix stability, as mutations in Col9a1, Col9a2, Col9a3, Comp, and Matn3 genes cause multiple epiphyseal dysplasia, in which patients develop early onset osteoarthritis. In mice, collagen IX ablation results in severely disturbed growth plate organization, hypocellular regions, and abnormal chondrocyte shape. This abnormal differentiation is likely to involve altered cell-matrix interactions but the mechanism is not known. To investigate the molecular basis of the collagen IX null phenotype we analyzed global differences in protein abundance between wild-type and knock-out femoral head cartilage by capillary HPLC tandem mass spectrometry. We identified 297 proteins in 3-day cartilage and 397 proteins in 21-day cartilage. Components that were differentially abundant between wild-type and collagen IX-deficient cartilage included 15 extracellular matrix proteins. Collagen IX ablation was associated with dramatically reduced COMP and matrilin-3, consistent with known interactions. Matrilin-1, matrilin-4, epiphycan, and thrombospondin-4 levels were reduced in collagen IX null cartilage, providing the first in vivo evidence for these proteins belonging to the collagen IX interactome. Thrombospondin-4 expression was reduced at the mRNA level, whereas matrilin-4 was verified as a novel collagen IX-binding protein. Furthermore, changes in TGFβ-induced protein βig-h3 and fibronectin abundance were found in the collagen IX knock-out but not associated with COMP ablation, indicating specific involvement in the abnormal collagen IX null cartilage. In addition, the more widespread expression of collagen XII in the collagen IX-deficient cartilage suggests an attempted compensatory response to the absence of collagen IX. Our differential proteomic analysis of cartilage is a novel approach to identify candidate matrix protein interactions in vivo, underpinning further analysis of mutant cartilage lacking other matrix components or harboring disease-causing mutations.
Kropp, Laura E.; Garg, Manish; Binder, Robert J.
2010-01-01
Cellular peptides generated by proteasomal degradation of proteins in the cytosol and destined for presentation by MHC I are associated with several chaperones. Hsp70, hsp90 and the TCP1-ring complex have been implicated as important cytosolic players for chaperoning these peptides. In this study we report that gp96 and calreticulin are essential for chaperoning peptides in the endoplasmic reticulum. Importantly we demonstrate that cellular peptides are transferred sequentially from gp96 to calreticulin and then to MHC I forming a relay line. Disruption of this relay line by removal of gp96 or calreticulin prevents the binding of peptides by MHC I and hence presentation of the MHC I-peptide complex on the cell surface. Our results are important for understanding how peptides are processed and trafficked within the endoplasmic reticulum before exiting in association with MHC I heavy chains and β2-microglobulin as a trimolecular complex. PMID:20410492
Growth stimulation of Porphyromonas endodontalis by hemoglobin and protoporphyrin IX.
Zerr, M A; Cox, C D; Johnson, W T; Drake, D R
2000-12-01
Porphyromonas endodontalis, like other Porphyromonas species, has a complex set of nutritional requirements. In addition to being an obligate anaerobe, the bacterium must be grown in a complex medium consisting of amino acids, reducing agents and heme compounds. P. endodontalis accumulates high concentrations of heme pigments to the extent that colonies appear black on blood agar. This accumulation of heme and the need for these compounds has been characterized as iron requirements by these species. However, in our studies, P. endodontalis demonstrated growth dependence on hemoglobin or protoporphyrin IX but not on free iron. Iron added to other heme compounds actually decreased growth stimulation by porphyrin-containing compounds. P. endodontalis actively transported free iron, but this process did not appear to be critical for growth. The maximum stimulation of growth by protoporphyrin IX, under conditions of iron deprivation, suggests that P. endodontalis requires the porphyrin moiety as a growth factor.
Robinson, James E.; Hastie, Kathryn M.; Cross, Robert W.; Yenni, Rachael E.; Elliott, Deborah H.; Rouelle, Julie A.; Kannadka, Chandrika B.; Smira, Ashley A.; Garry, Courtney E.; Bradley, Benjamin T.; Yu, Haini; Shaffer, Jeffrey G.; Boisen, Matt L.; Hartnett, Jessica N.; Zandonatti, Michelle A.; Rowland, Megan M.; Heinrich, Megan L.; Martínez-Sobrido, Luis; Cheng, Benson; de la Torre, Juan C.; Andersen, Kristian G.; Goba, Augustine; Momoh, Mambu; Fullah, Mohamed; Gbakie, Michael; Kanneh, Lansana; Koroma, Veronica J.; Fonnie, Richard; Jalloh, Simbirie C.; Kargbo, Brima; Vandi, Mohamed A.; Gbetuwa, Momoh; Ikponmwosa, Odia; Asogun, Danny A.; Okokhere, Peter O.; Follarin, Onikepe A.; Schieffelin, John S.; Pitts, Kelly R.; Geisbert, Joan B.; Kulakoski, Peter C.; Wilson, Russell B.; Happi, Christian T.; Sabeti, Pardis C.; Gevao, Sahr M.; Khan, S. Humarr; Grant, Donald S.; Geisbert, Thomas W.; Saphire, Erica Ollmann; Branco, Luis M.; Garry, Robert F.
2016-01-01
Lassa fever is a severe multisystem disease that often has haemorrhagic manifestations. The epitopes of the Lassa virus (LASV) surface glycoproteins recognized by naturally infected human hosts have not been identified or characterized. Here we have cloned 113 human monoclonal antibodies (mAbs) specific for LASV glycoproteins from memory B cells of Lassa fever survivors from West Africa. One-half bind the GP2 fusion subunit, one-fourth recognize the GP1 receptor-binding subunit and the remaining fourth are specific for the assembled glycoprotein complex, requiring both GP1 and GP2 subunits for recognition. Notably, of the 16 mAbs that neutralize LASV, 13 require the assembled glycoprotein complex for binding, while the remaining 3 require GP1 only. Compared with non-neutralizing mAbs, neutralizing mAbs have higher binding affinities and greater divergence from germline progenitors. Some mAbs potently neutralize all four LASV lineages. These insights from LASV human mAb characterization will guide strategies for immunotherapeutic development and vaccine design. PMID:27161536
Irritable bowel syndrome: A clinical review
Soares, Rosa LS
2014-01-01
Irritable bowel syndrome (IBS) remains a clinical challenge in the 21st century. It’s the most commonly diagnosed gastrointestinal condition and also the most common reason for referral to gastroenterology clinics. Its can affect up to one in five people at some point in their lives, and has a significantly impact of life quality and health care utilization. The prevalence varies according to country and criteria used to define IBS. Various mechanisms and theories have been proposed about its etiology, but the biopsychosocial model is the most currently accepted for IBS. The complex of symptoms would be the result of the interaction between psychological, behavioral, psychosocial and environmental factors. The diagnosis of IBS is not confirmed by a specific test or structural abnormality. It is made using criteria based on clinical symptoms such as Rome criteria, unless the symptoms are thought to be atypical. Today the Rome Criteria III is the current gold-standard for the diagnoses of IBS. Secure positive evidence of IBS by means of specific disease marker is currently not possible and cannot be currently recommended for routine diagnosis. There is still no clinical evidence to recommend the use of biomarkers in blood to diagnose IBS. However, a number of different changes in IBS patients were demonstrated in recent years, some of which can be used in the future as a diagnostic support. IBS has no definitive treatment but could be controlled by non-pharmacologic management eliminating of some exacerbating factors such certain drugs, stressor conditions and changes in dietary habits.The traditional pharmacologic management of IBS has been symptom based and several drugs have been used. However, the cornerstone of its therapy is a solid patient physician relationship. This review will provide a summary of pathophysiology, diagnostic criteria and current and emerging therapies for IBS. PMID:25232249
Bower, Joseph F; Green, Thomas D; Ross, Ted M
2004-10-25
DNA vaccines expressing the envelope (Env) of the human immunodeficiency virus type 1 (HIV-1) have been relatively ineffective at generating high-titer, long-lasting, neutralizing antibodies in a variety of animal models. In this study, DNA vaccines were constructed to express a fusion protein of the soluble human CD4 (sCD4) and the gp120 subunit of the HIV-1 envelope. To enhance the immunogenicity of the expressed fusion protein, three copies of the murine C3d (mC3d3) were added to the carboxyl terminus of the complex. Monoclonal antibodies that recognize CD4-induced epitopes on gp120 efficiently bound to sCD4-gp120 or sCD4-gp120-mC3d3. In addition, both sCD4-gp120 and sCD4-gp120-mC3d3 bound to cells expressing appropriate coreceptors in the absence of cell surface hCD4. Mice (BALB/c) vaccinated with DNA vaccines expressing either gp120-mC3d3 or sCD4-gp120-mC3d3 elicited antibodies that neutralized homologous virus infection. However, the use of sCD4-gp120-mC3d3-DNA elicited the highest titers of neutralizing antibodies that persisted after depletion of anti-hCD4 antibodies. Interestingly, only mice vaccinated with DNA expressing sCD4-gp120-mC3d3 had antibodies that elicited cross-protective neutralizing antibodies. The fusion of sCD4 to the HIV-1 envelope exposes neutralizing epitopes that elicit broad protective immunity when the fusion complex is coupled with the molecular adjuvant, C3d.
Trujillo, Logan T.; Stanfield, Candice T.; Vela, Ruben D.
2017-01-01
Converging evidence suggests that human cognition and behavior emerge from functional brain networks interacting on local and global scales. We investigated two information-theoretic measures of functional brain segregation and integration—interaction complexity CI(X), and integration I(X)—as applied to electroencephalographic (EEG) signals and how these measures are affected by choice of EEG reference. CI(X) is a statistical measure of the system entropy accounted for by interactions among its elements, whereas I(X) indexes the overall deviation from statistical independence of the individual elements of a system. We recorded 72 channels of scalp EEG from human participants who sat in a wakeful resting state (interleaved counterbalanced eyes-open and eyes-closed blocks). CI(X) and I(X) of the EEG signals were computed using four different EEG references: linked-mastoids (LM) reference, average (AVG) reference, a Laplacian (LAP) “reference-free” transformation, and an infinity (INF) reference estimated via the Reference Electrode Standardization Technique (REST). Fourier-based power spectral density (PSD), a standard measure of resting state activity, was computed for comparison and as a check of data integrity and quality. We also performed dipole source modeling in order to assess the accuracy of neural source CI(X) and I(X) estimates obtained from scalp-level EEG signals. CI(X) was largest for the LAP transformation, smallest for the LM reference, and at intermediate values for the AVG and INF references. I(X) was smallest for the LAP transformation, largest for the LM reference, and at intermediate values for the AVG and INF references. Furthermore, across all references, CI(X) and I(X) reliably distinguished between resting-state conditions (larger values for eyes-open vs. eyes-closed). These findings occurred in the context of the overall expected pattern of resting state PSD. Dipole modeling showed that simulated scalp EEG-level CI(X) and I(X) reflected changes in underlying neural source dependencies, but only for higher levels of integration and with highest accuracy for the LAP transformation. Our observations suggest that the Laplacian-transformation should be preferred for the computation of scalp-level CI(X) and I(X) due to its positive impact on EEG signal quality and statistics, reduction of volume-conduction, and the higher accuracy this provides when estimating scalp-level EEG complexity and integration. PMID:28790884
Shrivastava, Indira; LaLonde, Judith M.
2012-01-01
HIV infection is initiated by binding of the viral glycoprotein gp120, to the cellular receptor CD4. Upon CD4 binding, gp120 undergoes conformational change, permitting binding to the chemokine receptor. Crystal structures of gp120 ternary complex reveal the CD4 bound conformation of gp120. We report here the application of Gaussian Network Model (GNM) to the crystal structures of gp120 bound to CD4 or CD4 mimic and 17b, to study the collective motions of the gp120 core and determine the communication propensities of the residue network. The GNM fluctuation profiles identify residues in the inner domain and outer domain that may facilitate conformational change or stability, respectively. Communication propensities delineate a residue network that is topologically suited for signal propagation from the Phe43 cavity throughout the gp120 outer domain. . These results provide a new context for interpreting gp120 core envelope structure-function relationships. PMID:20718047
DOE Office of Scientific and Technical Information (OSTI.GOV)
York, Joanne; Nunberg, Jack H.
2007-03-01
The arenavirus envelope glycoprotein (GP-C) retains a cleaved and stable signal peptide (SSP) as an essential subunit of the mature complex. This 58-amino-acid residue peptide serves as a signal sequence and is additionally required to enable transit of the assembled GP-C complex to the Golgi, and for pH-dependent membrane fusion activity. We have investigated the C-terminal region of the Junin virus SSP to study the role of the cellular signal peptidase (SPase) in generating SSP. Site-directed mutagenesis at the cleavage site (positions - 1 and - 3) reveals a pattern of side-chain preferences consistent with those of SPase. Although positionmore » - 2 is degenerate for SPase cleavage, this residue in the arenavirus SSP is invariably a cysteine. In the Junin virus, this cysteine is not involved in disulfide bonding. We show that replacement with alanine or serine is tolerated for SPase cleavage but prevents the mutant SSP from associating with GP-C and enabling transport to the cell surface. Conversely, an arginine mutation at position - 1 that prevents SPase cleavage is fully compatible with GP-C-mediated membrane fusion activity when the mutant SSP is provided in trans. These results point to distinct roles of SSP sequences in SPase cleavage and GP-C biogenesis. Further studies of the unique structural organization of the GP-C complex will be important in identifying novel opportunities for antiviral intervention against arenaviral hemorrhagic disease.« less
NASA Astrophysics Data System (ADS)
Getman, Konstantin V.; Feigelson, Eric; Kuhn, Michael A.; Broos, Patrick S; Townsley, Leisa K.; Naylor, Tim; Povich, Matthew S.; Luhman, Kevin; Garmire, Gordon
2014-08-01
The MYStIX (Massive Young Star-Forming Complex Study in Infrared and X-ray) project seeks to characterize 20 OB-dominated young star forming regions (SFRs) at distances <4 kpc using photometric catalogs from the Chandra X-ray Observatory, Spitzer Space Telescope, UKIRT and 2MASS surveys. As part of the MYStIX project, we developed a new stellar chronometer that employs near-infrared and X-ray photometry data, AgeJX. Computing AgeJX averaged over MYStIX (sub)clusters reveals previously unknown age gradients across most of the MYStIX regions as well as within some individual rich clusters. Within the SFRs, the inferred AgeJX ages are youngest in obscured locations in molecular clouds, intermediate in revealed stellar clusters, and oldest in distributed stellar populations. Noticeable intra-cluster gradients are seen in the NGC 2024 (Flame Nebula) star cluster and the Orion Nebula Cluster (ONC): stars in cluster cores appear younger and thus were formed later than stars in cluster halos. The latter result has two important implications for the formation of young stellar clusters. Clusters likely form slowly: they do not arise from a single nearly-instantaneous burst of star formation. The simple models where clusters form inside-out are likely incorrect, and more complex models are needed. We provide several star formation scenarios that alone or in combination may lead to the observed core-halo age gradients.
Zhang, Yan; Niu, Yuzhen; Tian, Jiaqi; Liu, Xuewei; Yao, Xiaojun; Liu, Huanxiang
2017-12-01
N-linked glycans such as 234 and 276 gp 120 glycans are vital components of HIV evasion from humoral immunity and important for HIV-1 neutralization of many broadly neutralizing antibodies (bNAbs). However, it is unknown the action mechanism of two glycans. To investigate the roles of the glycans on the interactions of gp120 with CD4 and antibody, molecular dynamic simulations based on gp120-CD4-8ANC195 complex with 234 and 276 gp 120 glycans, 234 gp 120 glycan, 276 gp 120 glycan, and without glycan were performed. Our results reveal that 276 gp 120 glycan can enhance gp120-CD4 and gp120-antibody interactions through the formation of hydrogen bonds of the glycan with CD4 and antibody and make the binding interface of gp120, CD4 and antibody stable; 234 gp 120 glycan primarily reinforces gp120-antibody interactions and weakly affects gp120-CD4 interactions as it mainly lies between gp120 and antibody. The co-operating of two glycans can enhance gp120-CD4 and gp120-antibody associations. Through the structural analysis, it can be seen that 234 gp 120 glycan leads to moving upward of two glycans and the variable region of heavy chain, which is favorable for the interactions of gp120 with CD4 and antibody. The information obtained in this study can provide the guidance for design vaccines and small molecule inhibitors. © 2017 John Wiley & Sons A/S.
Hydrogen-bond formation between isoindolo[2,1-a]indol-6-one and aliphatic alcohols in n-hexane.
Demeter, Attila; Bérces, Tibor
2005-03-17
The spectroscopic, kinetic, and equilibrium properties of isoindolo[2,1-a]indol-6-one (I) were studied in n-hexane in the presence and absence of alcohols (X). Hydrogen-bonded-complex formation was found to occur between the alcohol and the ground state as well as the excited state of the I molecule. The spectra of I and its singly complexed derivative (IX) are similar; however, that of IX is red shifted. The extent of red shift increases with the hydrogen-bonding ability of the alcohol. Equilibrium constant measurements were made to determine the hydrogen-bond basicity (beta(2)(H)) for I and the singlet excited (1)I. The beta(2)(H) value for (1)I is found to be about twice that of the ground-state I. Time-resolved fluorescence decay measurements indicate that the reaction of singlet excited I with fluorinated alcohols is diffusion controlled, while the rate of complexation with nonfluorinated (weaker hydrogen bonding) aliphatic alcohols depends on the Gibbs energy change in the complexation reaction. The quantitative correlation between the rate coefficient of complexation of (1)I with alcohols and the Gibbs energy change in the complexation process allowed us to estimate the rate coefficient for the complexation of the ground-state I with alcohols. The formation of the singlet excited hydrogen-bonded complex is irreversible; (1)IX disappears in a first order and an alcohol induced second order reaction. The first order decay is predominantly due to internal conversion to the ground state, the rate of which depends on the ionization energy of the complexing alcohol.
A Model of Airflow and Diffusion in Complex Terrain (MADICT).
1985-11-01
104 , 784-792. Ludwig, F.L. 1982: "Effect of a Change in Atmospheric Stability on the Growth Rate of Puffs Used in Plume Simulation Models," J. Appl...INPUTS C IF (NOPUF.EQ.0)THEN DO 2305 K=1, NFUNCT DOTX (1, K) =DOTX (0, K) 2305 CONTINUE IHOUR=N I-IHOUR+1)NOPUF=NOPUFF +1 ""- END IF RETURN END 104 ...CM) C DO 100 IX-0,INDX DO 100 IY0.,INDY RHB (IXIyl)I = (XRuAS (IXIY’l MTIN /10.0 RHS1 (IX, IY 2)= (XCR1S (IX, IY, 2) -Z4IN /100. 0 IF(RHS (IXI,2
Lin, H; Rao, V B; Black, L W
1999-06-04
Bacteriophage DNA packaging results from an ATP-driven translocation of concatemeric DNA into the prohead by the phage terminase complexed with the portal vertex dodecamer of the prohead. Functional domains of the bacteriophage T4 terminase and portal gene 20 product (gp20) were determined by mutant analysis and sequence localization within the structural genes. Interaction regions of the portal vertex and large terminase subunit (gp17) were determined by genetic (terminase-portal intergenic suppressor mutations), biochemical (column retention of gp17 and inhibition of in vitro DNA packaging by gp20 peptides), and immunological (co-immunoprecipitation of polymerized gp20 peptide and gp17) studies. The specificity of the interaction was tested by means of a phage T4 HOC (highly antigenicoutercapsid protein) display system in which wild-type, cs20, and scrambled portal peptide sequences were displayed on the HOC protein of phage T4. Binding affinities of these recombinant phages as determined by the retention of these phages by a His-tag immobilized gp17 column, and by co-immunoprecipitation with purified terminase supported the specific nature of the portal protein and terminase interaction sites. In further support of specificity, a gp20 peptide corresponding to a portion of the identified site inhibited packaging whereas the scrambled sequence peptide did not block DNA packaging in vitro. The portal interaction site is localized to 28 residues in the central portion of the linear sequence of gp20 (524 residues). As judged by two pairs of intergenic portal-terminase suppressor mutations, two separate regions of the terminase large subunit gp17 (central and COOH-terminal) interact through hydrophobic contacts at the portal site. Although the terminase apparently interacts with this gp20 portal peptide, polyclonal antibody against the portal peptide appears unable to access it in the native structure, suggesting intimate association of gp20 and gp17 possibly internalizes terminase regions within the portal in the packasome complex. Both similarities and differences are seen in comparison to analogous sites which have been identified in phages T3 and lambda. Copyright 1999 Academic Press.
Cryopreservation alters the membrane and cytoskeletal protein profile of platelet microparticles.
Raynel, Sarah; Padula, Matthew P; Marks, Denese C; Johnson, Lacey
2015-10-01
Cryopreservation of platelets (PLTs) in dimethyl sulfoxide (DMSO) and storage at -80 °C extends the PLT shelf life to at least 2 years, allowing greater accessibility in military and rural environments. While cryopreserved PLTs have been extensively characterized, the microparticles formed as a result of cryopreservation are yet to be fully described. Apheresis PLTs were cryopreserved at -80 °C with 5% DMSO and sampled before freezing and after thawing. Microparticle number, size, surface receptor phenotype, and function were assessed by microscopy, flow cytometry, dynamic light scattering, and thrombin-generating capacity. Proteomic changes were examined using two-dimensional gel electrophoresis and Western blotting. PLT cryopreservation resulted in a 15-fold increase in the number of microparticles compared to fresh PLTs. The surface receptor phenotype of these microparticles differed to microparticles from fresh PLTs, with more microparticles expressing glycoprotein (GP)IV, GPIIb, and the GPIb-V-IX complex. Cryopreservation drastically altered the abundance of many cytoskeletal proteins in the PLT microparticles, including actin, filamin, gelsolin, and tropomyosin. Despite these changes, PLT microparticles were functional and contributed to phosphatidylserine- and tissue factor- induced thrombin generation. This study demonstrates that PLT microparticles formed by cryopreservation are phenotypically distinct from those present before freezing. These differences may be associated with the procoagulant properties of cryopreserved PLTs. © 2015 AABB.
Just, Sarah
2017-02-01
von Willebrand disease (VWD) was first described nearly a century ago in 1924 by Erik Adolf von Willebrand. Diagnostic testing at the time was very limited and it was not until the mid to late 1900s that more tests became available to assist with the diagnosis and classification of VWD. Two of these tests are based on ristocetin, one being ristocetin-induced platelet aggregation (RIPA) and the other the von Willebrand factor (VWF) ristocetin cofactor assay (VWF:RCo). The VWF:RCo assay provides functional assessment of in vitro VWF binding to the platelet glycoprotein (Gp) complex, GPIb-IX-V. Despite some advancements and newer technologies utilizing the principles of the original VWF:RCo assay, the original assay is still referred to as the gold standard for measurement of VWF activity. This article will review the history of VWD diagnostic assays, including RIPA and VWF:RCo over the past 40 years, as well as the newer assays that measure platelet binding with or without ristocetin, and which have been developed with the aim to potentially replace platelet-based ristocetin-dependent assays. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Insights from the structure of a smallpox virus topoisomerase-DNA transition state mimic
Perry, Kay; Hwang, Young; Bushman, Frederic D.; Van Duyne, Gregory D.
2010-01-01
Summary Poxviruses encode their own type IB topoisomerases (TopIBs) which release superhelical tension generated by replication and transcription of their genomes. To investigate the reaction catalyzed viral TopIBs, we have determined the structure of a variola virus topoisomerase-DNA complex trapped as a vanadate transition state mimic. The structure reveals how the viral TopIB enzymes are likely to position the DNA duplex for ligation following relaxation of supercoils and identifies the sources of friction observed in single molecule experiments that argue against free rotation. The structure also identifies a conformational change in the leaving group sugar that must occur prior to cleavage and reveals a mechanism for promoting ligation following relaxation of supercoils that involves a novel Asp-minor groove interaction. Overall, the new structural data support a common catalytic mechanism for the TopIB superfamily but indicate distinct methods for controlling duplex rotation in the small vs. large enzyme subfamilies. PMID:20152159
Kwong, Peter D.; Wyatt, Richard; Robinson, James; Sweet, Raymond W.; Sodroski, Joseph; Hendrickson, Wayne A.
2017-01-01
The entry of human immunodeficiency virus (HIV) into cells requires the sequential interaction of the viral exterior envelope glycoprotein, gp120, with the CD4 glycoprotein and a chemokine receptor on the cell surface. These interactions initiate a fusion of the viral and cellular membranes. Although gpl20 can elicit virus-neutralizing antibodies, HIV eludes the immune system. We have solved the X-ray crystal structure at 2.5 Å resolution of an HIV-1 gp120 core complexed with a two-domain fragment of human CD4 and an antigen-binding fragment of a neutralizing antibody that blocks chemokine-receptor binding. The structure reveals a cavity-laden CD4-gp120 interface, a conserved binding site for the chemokine receptor, evidence for a conformational change upon CD4 binding, the nature of a CD4-induced antibody epitope, and specific mechanisms for immune evasion. Our results provide a framework for understanding the complex biology of HIV entry into cells and should guide efforts to intervene. PMID:9641677
Llewellyn, Martin S.; Messenger, Louisa A.; Luquetti, Alejandro O.; Garcia, Lineth; Torrico, Faustino; Tavares, Suelene B. N.; Cheaib, Bachar; Derome, Nicolas; Delepine, Marc; Baulard, Céline; Deleuze, Jean-Francois; Sauer, Sascha; Miles, Michael A.
2015-01-01
Background Chagas disease results from infection with the diploid protozoan parasite Trypanosoma cruzi. T. cruzi is highly genetically diverse, and multiclonal infections in individual hosts are common, but little studied. In this study, we explore T. cruzi infection multiclonality in the context of age, sex and clinical profile among a cohort of chronic patients, as well as paired congenital cases from Cochabamba, Bolivia and Goias, Brazil using amplicon deep sequencing technology. Methodology/ Principal Findings A 450bp fragment of the trypomastigote TcGP63I surface protease gene was amplified and sequenced across 70 chronic and 22 congenital cases on the Illumina MiSeq platform. In addition, a second, mitochondrial target—ND5—was sequenced across the same cohort of cases. Several million reads were generated, and sequencing read depths were normalized within patient cohorts (Goias chronic, n = 43, Goias congenital n = 2, Bolivia chronic, n = 27; Bolivia congenital, n = 20), Among chronic cases, analyses of variance indicated no clear correlation between intra-host sequence diversity and age, sex or symptoms, while principal coordinate analyses showed no clustering by symptoms between patients. Between congenital pairs, we found evidence for the transmission of multiple sequence types from mother to infant, as well as widespread instances of novel genotypes in infants. Finally, non-synonymous to synonymous (dn:ds) nucleotide substitution ratios among sequences of TcGP63Ia and TcGP63Ib subfamilies within each cohort provided powerful evidence of strong diversifying selection at this locus. Conclusions/Significance Our results shed light on the diversity of parasite DTUs within each patient, as well as the extent to which parasite strains pass between mother and foetus in congenital cases. Although we were unable to find any evidence that parasite diversity accumulates with age in our study cohorts, putative diversifying selection within members of the TcGP63I gene family suggests a link between genetic diversity within this gene family and survival in the mammalian host. PMID:25849488
Tsang, S.W.; Auyeung, K.K.W.; Bian, Z.X.; Ko, J.K.S.
2016-01-01
Background Although the precise pathophysiology of irritable bowel syndrome (IBS) remains unknown, it is generally considered to be a disorder of the brain-gut axis, representing the disruption of communication between the brain and the digestive system. The present review describes advances in understanding the pathophysiology and experimental approaches in studying IBS, as well as providing an update of the therapies targeting brain-gut axis in the treatment of the disease. Methods Causal factors of IBS are reviewed. Following this, the preclinical experimental models of IBS will be introduced. Besides, both current and future therapeutic approaches of IBS will be discussed. Results When signal of the brain-gut axis becomes misinterpreted, it may lead to dysregulation of both central and enteric nervous systems, altered intestinal motility, increased visceral sensitivity and consequently contributing to the development of IBS. Interference of the brain-gut axis can be modulated by various psychological and environmental factors. Although there is no existing animal experiment that can represent this complex multifactorial disease, these in vivo models are clinically relevant readouts of gastrointestinal functions being essential to the identification of effective treatments of IBS symptoms as well as their molecular targets. Understanding the brain-gut axis is essential in developing the effective therapy for IBS. Therapies include improvement of GI motor functions, relief of visceral hypersensitivity and pain, attenuation of autonomic dysfunctions and suppression of mucosal immune activation. Conclusion Target-oriented therapies that provide symptomatic, psychological and physiological benefits could surely help to improve the quality of life of IBS patients. PMID:27009115
Introduction to Data Acquisition 3.Let’s Acquire Data!
NASA Astrophysics Data System (ADS)
Nakanishi, Hideya; Okumura, Haruhiko
In fusion experiments, diagnostic control and logging devices are usually connected through the field bus, e.g. GP-IB. Internet technologies are often applied for their remote operation. All equipment and digitizers are driven by pre-programmed sequences, in which clocks and triggers give the essential timing for data acquisition. Data production rate and amount must be checked in comparison with the transfer and store rates. To store binary raw data safely, journaling file systems are preferably used with redundant disks (RAID) or mirroring mechanism, such as “rsync”. A proper choice of the data compression method not only reduces the storage size but also improves the I/O throughputs. DBMS is even applicable to quick search or security around the table data.
Platelet receptors as therapeutic targets: Past, present and future.
Jamasbi, Janina; Ayabe, Keng; Goto, Shinya; Nieswandt, Bernhard; Peter, Karlheinz; Siess, Wolfgang
2017-06-28
Anti-platelet drugs reduce arterial thrombosis after plaque rupture and erosion, prevent stent thrombosis and are used to prevent and treat myocardial infarction and ischaemic stroke. Some of them may also be helpful in treating less frequent diseases such as thrombotic thrombocytopenic purpura. The present concise review aims to cover current and future developments of anti-platelet drugs interfering with the interaction of von Willebrand factor (VWF) with glycoprotein (GP) Ibα, and directed against GPVI, GPIIb/IIIa (integrin α IIb β 3 ), the thrombin receptor PAR-1, and the ADP receptor P2Y 12 . The high expectations of having novel antiplatelet drugs which selectively inhibit arterial thrombosis without interfering with normal haemostasis could possibly be met in the near future.
Liebold, D
2008-02-01
Since April 1, 2007 medical rehabilitation is a standard insurance benefit of the statutory health insurance scheme (covered by the SGB V, book 5 of the German social code), with the right of the beneficiary to comply especially with the intentions, the principles and the preconditions of the benefits as stipulated in the SGB IX (book 9 of the German social code covering rehabilitation and participation of persons with disabilities). In claiming benefits the applicable rules primarily are those of the SGB IX, as long as the SGB V does not contain different rules. In light of the demands of the SGB IX, the prevailing case law of the Federal Social Court concerning technical aids and assistive devices cannot persist any longer. The so-called "basic-compensation" is contradictory to the specifications of the SGB IX. Medical rehabilitation does not only consist of complex benefits, but every single benefit pursuant to section sign 26 Abs. 2, Abs. 3 SGB IX is a medical rehabilitation benefit if its priority intention is to achieve the beneficiary's participation in society.
Pontier, Dominique; Albrieux, Catherine; Joyard, Jacques; Lagrange, Thierry; Block, Maryse
2007-01-01
Protoporphyrin IX is the last common intermediate between the haem and chlorophyll biosynthesis pathways. The addition of Mg directs this molecule toward chlorophyll biosynthesis. The first step downstream from the branchpoint is catalyzed by the Mg chelatase and is a highly regulated process. The corresponding product, Mg protoporphyrin IX, has been proposed to play an important role as a signaling molecule implicated in plastid-to-nucleus communication. In order to get more information on the chlorophyll biosynthesis pathway and on Mg protoporphyrin IX derivative functions, we have identified an Mg protoporphyrin IX methyltransferase (CHLM) knock-out mutant in Arabidopsis in which the mutation induces a blockage downstream from Mg protoporphyrin IX and an accumulation of this chlorophyll biosynthesis intermediate. Our results demonstrate that the CHLM gene is essential for the formation of chlorophyll and subsequently for the formation of photosystems I and II and cyt b6f complexes. Analysis of gene expression in the chlm mutant provides an independent indication that Mg protoporphyrin IX is a negative effector of nuclear photosynthetic gene expression, as previously reported. Moreover, it suggests the possible implication of Mg protoporphyrin IX methylester, the product of CHLM, in chloroplast-to-nucleus signaling. Finally, post-transcriptional up-regulation of the level of the CHLH subunit of the Mg chelatase has been detected in the chlm mutant and most likely corresponds to specific accumulation of this protein inside plastids. This result suggests that the CHLH subunit might play an important regulatory role when the chlorophyll biosynthetic pathway is disrupted at this particular step. PMID:17135235
DOE Office of Scientific and Technical Information (OSTI.GOV)
Burri, Dominique J.; Pasquato, Antonella; Ramos da Palma, Joel
2013-02-05
Maturation of the arenavirus GP precursor (GPC) involves proteolytic processing by cellular signal peptidase and the proprotein convertase subtilisin kexin isozyme 1 (SKI-1)/site 1 protease (S1P), yielding a tripartite complex comprised of a stable signal peptide (SSP), the receptor-binding GP1, and the fusion-active transmembrane GP2. Here we investigated the roles of SKI-1/S1P processing and SSP in the biosynthesis of the recombinant GP ectodomains of lymphocytic choriomeningitis virus (LCMV) and Lassa virus (LASV). When expressed in mammalian cells, the LCMV and LASV GP ectodomains underwent processing by SKI-1/S1P, followed by dissociation of GP1 from GP2. The GP2 ectodomain spontaneously formed trimersmore » as revealed by chemical cross-linking. The endogenous SSP, known to be crucial for maturation and transport of full-length arenavirus GPC was dispensable for processing and secretion of the soluble GP ectodomain, suggesting a specific role of SSP in the stable prefusion conformation and transport of full-length GPC.« less
SU-E-T-647: Quality Assurance of VMAT by Gamma Analysis Dependence On Low-Dose Threshold
DOE Office of Scientific and Technical Information (OSTI.GOV)
Song, J; Kim, M; Lee, S
2015-06-15
Purpose: The AAPM TG-119 instructed institutions to use low-dose threshold (LDT) of 10% or a ROI determined by the jaw when they collected gamma analysis QA data of planar dose distribution. Also, based on a survey by Nelms and Simon, more than 70% of institutions use a LDT between 0% and 10% for gamma analysis. However, there are no clinical data to quantitatively demonstrate the impact of the LDT on the gamma index. Therefore, we performed a gamma analysis with LDTs of 0% to 15% according to both global and local normalization and different acceptance criteria: 3%/3 mm, 2%/2 mm,more » and 1%/1 mm. Methods: A total of 30 treatment plans—10 head and neck, 10 brain, and 10 prostate cancer cases—were randomly selected from the Varian Eclipse TPS, retrospectively. For the gamma analysis, a predicted portal image was acquired through a portal dose calculation algorithm in the Eclipse TPS, and a measured portal image was obtained using a Varian Clinac iX and an EPID. Then, the gamma analysis was performed using the Portal Dosimetry software. Results: For the global normalization, the gamma passing rate (%GP) decreased as the LDT increased, and all cases of low-dose thresholds exhibited a %GP above 95% for both the 3%/3 mm and 2%/2 mm criteria. However, for local normalization, the %GP increased as LDT increased. The gamma passing rate with LDT of 10% increased by 6.86%, 9.22% and 6.14% compared with the 0% in the case of the head and neck, brain and prostate for 3%/3 mm criteria, respectively. Conclusion: Applying the LDT in the global normalization does not have critical impact to judge patient-specific QA results. However, LDT for the local normalization should be carefully selected because applying the LDT could affect the average of the %GP to increase rapidly.« less
Canon, Francis; Paté, Franck; Meudec, Emmanuelle; Marlin, Thérèse; Cheynier, Véronique; Giuliani, Alexandre; Sarni-Manchado, Pascale
2009-12-01
Numerous protein-polyphenol interactions occur in biological and food domains particularly involving proline-rich proteins, which are representative of the intrinsically unstructured protein group (IUP). Noncovalent protein-ligand complexes are readily detected by electrospray ionization mass spectrometry (ESI-MS), which also gives access to ligand binding stoichiometry. Surprisingly, the study of interactions between polyphenolic molecules and proteins is still an area where ESI-MS has poorly benefited, whereas it has been extensively applied to the detection of noncovalent complexes. Electrospray ionization mass spectrometry has been applied to the detection and the characterization of the complexes formed between tannins and a human salivary proline-rich protein (PRP), namely IB5. The study of the complex stability was achieved by low-energy collision-induced dissociation (CID) measurements, which are commonly implemented using triple quadrupole, hybrid quadrupole time-of-flight, or ion trap instruments. Complexes composed of IB5 bound to a model polyphenol EgCG have been detected by ESI-MS and further analyzed by MS/MS. Mild ESI interface conditions allowed us to observe intact noncovalent PRP-tannin complexes with stoichiometries ranging from 1:1 to 1:5. Thus, ESI-MS shows its efficiency for (1) the study of PRP-tannin interactions, (2) the determination of stoichiometry, and (3) the study of complex stability. We were able to establish unambiguously both their stoichiometries and their overall subunit architecture via tandem mass spectrometry and solution disruption experiments. Our results prove that IB5.EgCG complexes are maintained intact in the gas phase.
Nishigaki, Kazuo; Thompson, Delores; Hanson, Charlotte; Yugawa, Takashi; Ruscetti, Sandra
2001-01-01
The Friend spleen focus-forming virus (SFFV) encodes a unique envelope glycoprotein, gp55, which allows erythroid cells to proliferate and differentiate in the absence of erythropoietin (Epo). SFFV gp55 has been shown to interact with the Epo receptor complex, causing constitutive activation of various signal-transducing molecules. When injected into adult mice, SFFV induces a rapid erythroleukemia, with susceptibility being determined by the host gene Fv-2, which was recently shown to be identical to the gene encoding the receptor tyrosine kinase Stk/Ron. Susceptible, but not resistant, mice encode not only full-length Stk but also a truncated form of the kinase, sf-Stk, which may mediate the biological effects of SFFV infection. To determine whether expression of SFFV gp55 leads to the activation of sf-Stk, we expressed sf-Stk, with or without SFFV gp55, in hematopoietic cells expressing the Epo receptor. Our data indicate that sf-Stk interacts with SFFV gp55 as well as gp55P, the biologically active form of the viral glycoprotein, forming disulfide-linked complexes. This covalent interaction, as well as noncovalent interactions with SFFV gp55, results in constitutive tyrosine phosphorylation of sf-Stk and its association with multiple tyrosine-phosphorylated signal-transducing molecules. In contrast, neither Epo stimulation in the absence of SFFV gp55 expression nor expression of a mutant of SFFV that cannot interact with sf-Stk was able to induce tyrosine phosphorylation of sf-Stk or its association with any signal-transducing molecules. Covalent interaction of sf-Stk with SFFV gp55 and constitutive tyrosine phosphorylation of sf-Stk can also be detected in an erythroleukemia cell line derived from an SFFV-infected mouse. Our results suggest that SFFV gp55 may mediate its biological effects in vivo by interacting with and activating a truncated form of the receptor tyrosine kinase Stk. PMID:11483734
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bower, Joseph F.; Green, Thomas D.; Ross, Ted M.
2004-10-25
DNA vaccines expressing the envelope (Env) of the human immunodeficiency virus type 1 (HIV-1) have been relatively ineffective at generating high-titer, long-lasting, neutralizing antibodies in a variety of animal models. In this study, DNA vaccines were constructed to express a fusion protein of the soluble human CD4 (sCD4) and the gp120 subunit of the HIV-1 envelope. To enhance the immunogenicity of the expressed fusion protein, three copies of the murine C3d (mC3d{sub 3}) were added to the carboxyl terminus of the complex. Monoclonal antibodies that recognize CD4-induced epitopes on gp120 efficiently bound to sCD4-gp120 or sCD4-gp120-mC3d{sub 3}. In addition, bothmore » sCD4-gp120 and sCD4-gp120-mC3d{sub 3} bound to cells expressing appropriate coreceptors in the absence of cell surface hCD4. Mice (BALB/c) vaccinated with DNA vaccines expressing either gp120-mC3d{sub 3} or sCD4-gp120-mC3d{sub 3} elicited antibodies that neutralized homologous virus infection. However, the use of sCD4-gp120-mC3d{sub 3}-DNA elicited the highest titers of neutralizing antibodies that persisted after depletion of anti-hCD4 antibodies. Interestingly, only mice vaccinated with DNA expressing sCD4-gp120-mC3d{sub 3} had antibodies that elicited cross-protective neutralizing antibodies. The fusion of sCD4 to the HIV-1 envelope exposes neutralizing epitopes that elicit broad protective immunity when the fusion complex is coupled with the molecular adjuvant, C3d.« less
Mechanism of human antibody-mediated neutralization of Marburg virus.
Flyak, Andrew I; Ilinykh, Philipp A; Murin, Charles D; Garron, Tania; Shen, Xiaoli; Fusco, Marnie L; Hashiguchi, Takao; Bornholdt, Zachary A; Slaughter, James C; Sapparapu, Gopal; Klages, Curtis; Ksiazek, Thomas G; Ward, Andrew B; Saphire, Erica Ollmann; Bukreyev, Alexander; Crowe, James E
2015-02-26
The mechanisms by which neutralizing antibodies inhibit Marburg virus (MARV) are not known. We isolated a panel of neutralizing antibodies from a human MARV survivor that bind to MARV glycoprotein (GP) and compete for binding to a single major antigenic site. Remarkably, several of the antibodies also bind to Ebola virus (EBOV) GP. Single-particle EM structures of antibody-GP complexes reveal that all of the neutralizing antibodies bind to MARV GP at or near the predicted region of the receptor-binding site. The presence of the glycan cap or mucin-like domain blocks binding of neutralizing antibodies to EBOV GP, but not to MARV GP. The data suggest that MARV-neutralizing antibodies inhibit virus by binding to infectious virions at the exposed MARV receptor-binding site, revealing a mechanism of filovirus inhibition. Copyright © 2015 Elsevier Inc. All rights reserved.
Gurbel, Paul A; Cummings, Charles C; Bell, Christopher R; Alford, Amanda B; Meister, Andrew F; Serebruany, Victor L
2003-02-01
Despite the common practice of clopidogrel loading for coronary stenting, the time dependence and degree of platelet inhibition after this therapy are not well defined. We sought to establish an optimal clopidogrel dosing regimen for sustained platelet inhibition in stented patients. Platelets were assessed by conventional aggregation with 5 micromol/L adenosine diphosphate (ADP), 1 microg/mL collagen (COLL), and 750 micromol/L arachidonic acid; whole blood aggregation by 1 microg/mL collagen (WBA); shear-induced closure time (CT); contractile force (CF); and expression of 9 surface receptors by flow cytometry in 100 patients undergoing elective stent placement without glycoprotein (GP) IIb/IIIa receptor antagonists. Blood was obtained at baseline and serially over 5 days poststenting after different clopidogrel loading regimens: 300 mg 24 hours before (Group A), 12 hours before (Group B), 3 to 6 hours before (Group C), and 75 mg at the time of intervention (Group D). Before stenting, ADP, COLL, CT, and WBA were reduced by clopidogrel loading (P <.05). CF was not affected by clopidogrel. Before stenting, GP IIb/IIIa expression increased in groups A through C (P <.05), whereas PECAM-1 and CD107a were reduced (P <.05). At 2 hours and 2 days poststenting, platelets, in general, exhibited an increase in activity that was most inhibited by clopidogrel loading. Clopidogrel inhibited GP Ib, platelet/endothelial cell adhesion molecule-1, CD 107a, CD 151, and GP IIb/IIIa expression at day 5 poststenting. A 300 mg clopidogrel load given 3 to 24 hours before stenting inhibits platelets at the time of the procedure and reduces poststent activity more than a 75 mg dose given at the time of the procedure. The inhibition of adhesive molecule expression may also contribute an antithrombotic effect. Poststent activation of platelets may warrant higher periprocedural dosing.
Chen, Zengsheng; Koenig, Steven C; Slaughter, Mark S; Griffith, Bartley P; Wu, Zhongjun J
2017-11-07
The structural integrity of platelet receptors is essential for platelets to play the normal hemostatic function. The high non-physiologic shear stress (NPSS) commonly exists in blood-contacting medical devices and has been shown to cause platelet receptor shedding. The loss of platelet receptors may impair the normal hemostatic function of platelets. The aim of this study was to quantify NPSS-induced shedding of three key receptors on the platelet surface. Human blood was subjected to the matrix of well-defined shear stresses and exposure times, generated by using a custom-designed blood-shearing device. The expression of three key platelet receptors, glycoprotein (GP) Ibα, GPVI, and GPIIb/IIIa, in sheared blood was quantified using flow cytometry. The quantitative relationship between the loss of each of the three receptors on the platelet surface and shear condition (shear stress level and exposure time) was explored. It was found that these relationships followed well the power law functional form. The coefficients of the power law models for the shear-induced shedding of these platelet receptors were derived with coefficients of determination (R) of 0.77, 0.73, and 0.78, respectively. The power law models with these coefficients may be potentially used to predict the shear-induced platelet receptor shedding of human blood.
Application of an E. coli signal sequence as a versatile inclusion body tag.
Jong, Wouter S P; Vikström, David; Houben, Diane; van den Berg van Saparoea, H Bart; de Gier, Jan-Willem; Luirink, Joen
2017-03-21
Heterologous protein production in Escherichia coli often suffers from bottlenecks such as proteolytic degradation, complex purification procedures and toxicity towards the expression host. Production of proteins in an insoluble form in inclusion bodies (IBs) can alleviate these problems. Unfortunately, the propensity of heterologous proteins to form IBs is variable and difficult to predict. Hence, fusing the target protein to an aggregation prone polypeptide or IB-tag is a useful strategy to produce difficult-to-express proteins in an insoluble form. When screening for signal sequences that mediate optimal targeting of heterologous proteins to the periplasmic space of E. coli, we observed that fusion to the 39 amino acid signal sequence of E. coli TorA (ssTorA) did not promote targeting but rather directed high-level expression of the human proteins hEGF, Pla2 and IL-3 in IBs. Further analysis revealed that ssTorA even mediated IB formation of the highly soluble endogenous E. coli proteins TrxA and MBP. The ssTorA also induced aggregation when fused to the C-terminus of target proteins and appeared functional as IB-tag in E. coli K-12 as well as B strains. An additive effect on IB-formation was observed upon fusion of multiple ssTorA sequences in tandem, provoking almost complete aggregation of TrxA and MBP. The ssTorA-moiety was successfully used to produce the intrinsically unstable hEGF and the toxic fusion partner SymE, demonstrating its applicability as an IB-tag for difficult-to-express and toxic proteins. We present proof-of-concept for the use of ssTorA as a small, versatile tag for robust E. coli-based expression of heterologous proteins in IBs.
Hallée, Stéphanie; Thériault, Catherine; Gagnon, Dominic; Kehrer, Jessica; Frischknecht, Friedrich; Mair, Gunnar R; Richard, Dave
2018-03-26
Compared with other eukaryotic cell types, malaria parasites appear to possess a more rudimentary Golgi apparatus being composed of dispersed, unstacked cis and trans-cisternae. Despite playing a central role in the secretory pathway of the parasite, few Plasmodium Golgi resident proteins have been characterised. We had previously identified a new Golgi resident protein of unknown function, which we had named Golgi Protein 1, and now show that it forms a complex with a previously uncharacterised transmembrane protein (Golgi Protein 2, GP2). The Golgi Protein complex localises to the cis-Golgi throughout the erythrocytic cycle and potentially also during the mosquito stages. Analysis of parasite strains where GP1 expression is conditionally repressed and/or the GP2 gene is inactivated reveals that though the Golgi protein complex is not essential at any stage of the parasite life cycle, it is important for optimal asexual development in the blood stages. © 2018 John Wiley & Sons Ltd.
Yamamoto, N; Schneider, J; Hinuma, Y; Hunsmann, G
1982-01-01
A glycoprotein of an apparent molecular mass of 46,000, gp 46, was enriched by affinity chromatography from the virus- and cell-free culture medium of adult T-cell leukemia virus (ATLV) infected cells. gp 46 was specifically precipitated with sera from patients with adult T-cell leukemia associated antigen (ATLA). Thus, gp 46 is a novel component of the ATLA antigen complex.
Induction of human immunodeficiency virus neutralizing antibodies using fusion complexes.
Zipeto, Donato; Matucci, Andrea; Ripamonti, Chiara; Scarlatti, Gabriella; Rossolillo, Paola; Turci, Marco; Sartoris, Silvia; Tridente, Giuseppe; Bertazzoni, Umberto
2006-05-01
Human immunodeficiency virus-1 (HIV-1) infects cells by membrane fusion that is mediated by the envelope proteins gp120/gp41 and the cellular receptors CD4 and CCR5. During this process, some conserved viral epitopes are temporarily exposed and may induce a neutralizing antibody response when fixed in the fusogenic conformation. These transient structures are conserved and may be effective antigens for use in an anti-HIV-1 vaccine. In this study we tested different conditions of preparation of fusion complexes inducing neutralizing antibodies against both R5 and X4 tropic HIV-1 strains. Cell lines expressing HIV-1 gp120/gp41 and CD4-CCR5 were prepared and conditions for producing fusion complexes were tested. Complexes produced at different temperature and fixative combinations were used to immunize mice. Results indicated that (a) fusion complexes prepared at either 21 degrees C, 30 degrees C or 37 degrees C were immunogenic and induced neutralizing antibodies against both R5 and X4 HIV-1 heterologous isolates; (b) after extensive purification of antibodies there was no cytotoxic effect; (c) complexes prepared at 37 degrees C were more immunogenic and induced higher titers of neutralizing antibodies than complexes prepared at either 21 degrees C or 30 degrees C; (d) the fixative used did not affect the titer of neutralizing antibodies except for glutaraldehyde which was ineffective; (e) the neutralizing activity was retained after CD4-CCR5 antibody removal. The production of higher titers of neutralizing antibody with fusion complexes prepared at 37 degrees C, as compared to lower temperatures, may be related to the induction of antibodies against many different conformation intermediates that subsequently act synergistically at different steps in the fusion process.
Gustchina, Elena; Li, Mi; Ghirlando, Rodolfo; Schuck, Peter; Louis, John M.; Pierson, Jason; Rao, Prashant; Subramaniam, Sriram; Gustchina, Alla; Clore, G. Marius; Wlodawer, Alexander
2013-01-01
A series of mini-antibodies (monovalent and bivalent Fabs) targeting the conserved internal trimeric coiled-coil of the N-heptad repeat (N-HR) of HIV-1 gp41 has been previously constructed and reported. Crystal structures of two closely related monovalent Fabs, one (Fab 8066) broadly neutralizing across a wide panel of HIV-1 subtype B and C viruses, and the other (Fab 8062) non-neutralizing, representing the extremes of this series, were previously solved as complexes with 5-Helix, a gp41 pre-hairpin intermediate mimetic. Binding of these Fabs to covalently stabilized chimeric trimers of N-peptides of HIV-1 gp41 (named (CCIZN36)3 or 3-H) has now been investigated using X-ray crystallography, cryo-electron microscopy, and a variety of biophysical methods. Crystal structures of the complexes between 3-H and Fab 8066 and Fab 8062 were determined at 2.8 and 3.0 Å resolution, respectively. Although the structures of the complexes with the neutralizing Fab 8066 and its non-neutralizing counterpart Fab 8062 were generally similar, small differences between them could be correlated with the biological properties of these antibodies. The conformations of the corresponding CDRs of each antibody in the complexes with 3-H and 5-Helix are very similar. The adaptation to a different target upon complex formation is predominantly achieved by changes in the structure of the trimer of N-HR helices, as well as by adjustment of the orientation of the Fab molecule relative to the N-HR in the complex, via rigid-body movement. The structural data presented here indicate that binding of three Fabs 8062 with high affinity requires more significant changes in the structure of the N-HR trimer compared to binding of Fab 8066. A comparative analysis of the structures of Fabs complexed to different gp41 intermediate mimetics allows further evaluation of biological relevance for generation of neutralizing antibodies, as well as provides novel structural insights into immunogen design. PMID:24244293
Management of functional abdominal pain and irritable bowel syndrome in children and adolescents.
Chiou, Eric; Nurko, Samuel
2010-06-01
Functional abdominal pain (FAP) and irritable bowel syndrome (IBS) are among the most commonly diagnosed medical problems in pediatrics. Symptom-based Rome III criteria for FAP and IBS have been validated and help the clinician in making a positive diagnosis. The majority of patients with mild complaints improve with reassurance and time. For a distinct subset of patients with more severe and disabling illness, finding effective treatment for these disorders remains a challenge. Over the years, a wide range of therapies have been proposed and studied. The lack of a single, proven intervention highlights the complex interplay of biopsychosocial factors probably involved in the development of childhood FAP and IBS, and the need for a multidisciplinary, integrated approach. This article reviews the current literature on the efficacy of pharmacologic, dietary and psychosocial interventions for FAP and IBS in children and adolescents.
Functional abdominal pain and irritable bowel syndrome in children and adolescents
Chiou, Eric; Nurko, Samuel
2011-01-01
Functional abdominal pain (FAP) and irritable bowel syndrome (IBS) are both associated with recurrent abdominal pain and are among the most commonly diagnosed medical problems in pediatrics. The majority of patients with mild complaints improve with reassurance and time. For a distinct subset of patients with more severe and disabling illness, finding effective treatment for these disorders remains a challenge. Based on the biopsychosocial model of functional disease, the Rome III criteria have helped frame FAP and IBS in terms of being a positive diagnosis and not a diagnosis of exclusion. However, the lack of a single, proven intervention highlights the complex interplay of pathologic mechanisms likely involved in the development of childhood FAP and IBS and the need for a multidisciplinary, integrated approach. This article discusses the epidemiology, proposed mechanisms, clinical approach and therapeutic options for the management of FAP and IBS in children and adolescents. PMID:21731470
NASA Astrophysics Data System (ADS)
Ivanov, Andrei V.; Gradyushko, A. T.; Laptev, V. P.; Panferova, N. G.; Varlamov, V. P.; Klyashchitsky, B. A.; Reshetnickov, Andrei V.; Ponomarev, Gelii V.
1996-01-01
The kinetics of photosensitizer distribution and elimination have been studied using fluorescent methods in organs and tumors of A/Snell mice with embriocarcinoma inoculated into their thigh muscles for the porphyrin compound 2,4-di((alpha) -methoxyethyl)deuteroporphyrin-- IX (DMH, `Dimehin') and its complex with polysaccharide chitosan. DMH fluorescence differs in samples of liver and faeces which follows from the spectra comparison. DMH is metabolizable upon passing through liver into a form eliminated by the gastrointestinal tract as our pharmacokinetic data have shown. DMH has been found to be a short-term highly photodynamically efficient photosensitizer judging by combined analysis of our toxicological, pharmacokinetic and photodynamic research data. DMH-chitosan uptake and distribution studies have shown the complex's long-term persistence in blood circulation, high level accumulation in spleen and lungs, whereas there was no complex registered in tumors and other tissues following i.v. administration.
Schnapp, A; Clos, J; Hädelt, W; Schreck, R; Cvekl, A; Grummt, I
1990-03-25
The murine ribosomal gene promoter contains two cis-acting control elements which operate in concert to promote efficient and accurate transcription initiation by RNA polymerase I. The start site proximal core element which is indispensable for promoter recognition by RNA polymerase I (pol I) encompasses sequences from position -39 to -1. An upstream control element (UCE) which is located between nucleotides -142 and -112 stimulates the efficiency of transcription initiation both in vivo and in vitro. Here we report the isolation and functional characterization of a specific rDNA binding protein, the transcription initiation factor TIF-IB, which specifically interacts with the core region of the mouse ribosomal RNA gene promoter. Highly purified TIF-IB complements transcriptional activity in the presence of two other essential initiation factors TIF-IA and TIF-IC. We demonstrate that the binding efficiency of purified TIF-IB to the core promoter is strongly enhanced by the presence in cis of the UCE. This positive effect of upstream sequences on TIF-IB binding is observed throughout the purification procedure suggesting that the synergistic action of the two distant promoter elements is not mediated by a protein different from TIF-IB. Increasing the distance between both control elements still facilitates stable factor binding but eliminates transcriptional activation. The results demonstrate that TIF-IB binding to the rDNA promoter is an essential early step in the assembly of a functional transcription initiation complex. The subsequent interaction of TIF-IB with other auxiliary transcription initiation factors, however, requires the correct spacing between the UCE and the core promoter element.
Inhibition of EBV-mediated membrane fusion by anti-gHgL antibodies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sathiyamoorthy, Karthik; Jiang, Jiansen; Mohl, Britta S.
Herpesvirus entry into cells requires the coordinated action of multiple virus envelope glycoproteins, including gH, gL, and gB. For EBV, the gp42 protein assembles into complexes with gHgL heterodimers and binds HLA class II to activate gB-mediated membrane fusion with B cells. EBV tropism is dictated by gp42 levels in the virion, as it inhibits entry into epithelial cells while promoting entry into B cells. The gHgL and gB proteins are targets of neutralizing antibodies and potential candidates for subunit vaccine development, but our understanding of their neutralizing epitopes and the mechanisms of inhibition remain relatively unexplored. Here we studiedmore » the structures and mechanisms of two anti-gHgL antibodies, CL40 and CL59, that block membrane fusion with both B cells and epithelial cells. We determined the structures of the CL40 and CL59 complexes with gHgL using X-ray crystallography and EM to identify their epitope locations. CL59 binds to the C-terminal domain IV of gH, while CL40 binds to a site occupied by the gp42 receptor binding domain. CL40 binding to gHgL/gp42 complexes is not blocked by gp42 and does not interfere with gp42 binding to HLA class II, indicating that its ability to block membrane fusion with B cells represents a defect in gB activation. Furthermore, these data indicate that anti-gHgL neutralizing antibodies can block gHgL-mediated activation of gB through different surface epitopes and mechanisms.« less
Inhibition of EBV-mediated membrane fusion by anti-gHgL antibodies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sathiyamoorthy, Karthik; Jiang, Jiansen; Möhl, Britta S.
Herpesvirus entry into cells requires the coordinated action of multiple virus envelope glycoproteins, including gH, gL, and gB. For EBV, the gp42 protein assembles into complexes with gHgL heterodimers and binds HLA class II to activate gB-mediated membrane fusion with B cells. EBV tropism is dictated by gp42 levels in the virion, as it inhibits entry into epithelial cells while promoting entry into B cells. The gHgL and gB proteins are targets of neutralizing antibodies and potential candidates for subunit vaccine development, but our understanding of their neutralizing epitopes and the mechanisms of inhibition remain relatively unexplored. Here we studiedmore » the structures and mechanisms of two anti-gHgL antibodies, CL40 and CL59, that block membrane fusion with both B cells and epithelial cells. We determined the structures of the CL40 and CL59 complexes with gHgL using X-ray crystallography and EM to identify their epitope locations. CL59 binds to the C-terminal domain IV of gH, while CL40 binds to a site occupied by the gp42 receptor binding domain. CL40 binding to gHgL/gp42 complexes is not blocked by gp42 and does not interfere with gp42 binding to HLA class II, indicating that its ability to block membrane fusion with B cells represents a defect in gB activation. These data indicate that anti-gHgL neutralizing antibodies can block gHgL-mediated activation of gB through different surface epitopes and mechanisms.« less
Inhibition of EBV-mediated membrane fusion by anti-gHgL antibodies
Sathiyamoorthy, Karthik; Jiang, Jiansen; Mohl, Britta S.; ...
2017-09-22
Herpesvirus entry into cells requires the coordinated action of multiple virus envelope glycoproteins, including gH, gL, and gB. For EBV, the gp42 protein assembles into complexes with gHgL heterodimers and binds HLA class II to activate gB-mediated membrane fusion with B cells. EBV tropism is dictated by gp42 levels in the virion, as it inhibits entry into epithelial cells while promoting entry into B cells. The gHgL and gB proteins are targets of neutralizing antibodies and potential candidates for subunit vaccine development, but our understanding of their neutralizing epitopes and the mechanisms of inhibition remain relatively unexplored. Here we studiedmore » the structures and mechanisms of two anti-gHgL antibodies, CL40 and CL59, that block membrane fusion with both B cells and epithelial cells. We determined the structures of the CL40 and CL59 complexes with gHgL using X-ray crystallography and EM to identify their epitope locations. CL59 binds to the C-terminal domain IV of gH, while CL40 binds to a site occupied by the gp42 receptor binding domain. CL40 binding to gHgL/gp42 complexes is not blocked by gp42 and does not interfere with gp42 binding to HLA class II, indicating that its ability to block membrane fusion with B cells represents a defect in gB activation. Furthermore, these data indicate that anti-gHgL neutralizing antibodies can block gHgL-mediated activation of gB through different surface epitopes and mechanisms.« less
Dey, Antu K.; Burke, Brian; Sun, Yide; Sirokman, Klara; Nandi, Avishek; Hartog, Karin; Lian, Ying; Geonnotti, Anthony R.; Montefiori, David; Franti, Michael; Martin, Grégoire; Carfi, Andrea; Kessler, Pascal; Martin, Loïc; Srivastava, Indresh K.; Barnett, Susan W.
2012-01-01
The identification of HIV-1 envelope glycoprotein (Env) structures that can generate broadly neutralizing antibodies (BNAbs) is pivotal to the development of a successful vaccine against HIV-1 aimed at eliciting effective humoral immune responses. To that end, the production of novel Env structure(s) that might induce BNAbs by presentation of conserved epitopes, which are otherwise occluded, is critical. Here, we focus on a structure that stabilizes Env in a conformation representative of its primary (CD4) receptor-bound state, thereby exposing highly conserved “CD4 induced” (CD4i) epitope(s) known to be important for co-receptor binding and subsequent virus infection. A CD4-mimetic miniprotein, miniCD4 (M64U1-SH), was produced and covalently complexed to recombinant, trimeric gp140 envelope glycoprotein (gp140) using site-specific disulfide linkages. The resulting gp140-miniCD4 (gp140-S-S-M64U1) complex was recognized by CD4i antibodies and the HIV-1 co-receptor, CCR5. The gp140-miniCD4 complex elicited the highest titers of CD4i binding antibodies as well as enhanced neutralizing antibodies against Tier 1 viruses as compared to gp140 protein alone following immunization of rabbits. Neutralization against HIV-27312/V434M and additional serum mapping confirm the specific elicitation of antibodies directed to the CD4i epitope(s). These results demonstrate the utility of structure-based approach in improving immunogenic response against specific region, such as the CD4i epitope(s) here, and its potential role in vaccine application. PMID:22291921
Genetic programming approach to evaluate complexity of texture images
NASA Astrophysics Data System (ADS)
Ciocca, Gianluigi; Corchs, Silvia; Gasparini, Francesca
2016-11-01
We adopt genetic programming (GP) to define a measure that can predict complexity perception of texture images. We perform psychophysical experiments on three different datasets to collect data on the perceived complexity. The subjective data are used for training, validation, and test of the proposed measure. These data are also used to evaluate several possible candidate measures of texture complexity related to both low level and high level image features. We select four of them (namely roughness, number of regions, chroma variance, and memorability) to be combined in a GP framework. This approach allows a nonlinear combination of the measures and could give hints on how the related image features interact in complexity perception. The proposed complexity measure M exhibits Pearson correlation coefficients of 0.890 on the training set, 0.728 on the validation set, and 0.724 on the test set. M outperforms each of all the single measures considered. From the statistical analysis of different GP candidate solutions, we found that the roughness measure evaluated on the gray level image is the most dominant one, followed by the memorability, the number of regions, and finally the chroma variance.
Rivera, C E; Villagra, J; Riordan, M; Williams, S; Lindstrom, K J; Rick, M E
2001-01-01
We describe a new mutation in glycoprotein IX (GPIX) in a patient with Bernard-Soulier syndrome (BSS). Sequencing of GPIX revealed a homozygous (T-->C) transition at nucleotide 1717 (GenBank/HUMGPIX/M80478), resulting in a Cys(8) (TGT)-->Arg (CGT) replacement in the mature peptide. DNA restriction enzyme analysis using BsaAI revealed that the patient was homozygous and that his parents were heterozygous for the defect. This mutation disrupts a putative disulphide bond between the Cys(8) and Cys(12) that would alter the secondary structure of GPIX and which probably accounts for the absence of the GPIb/IX/V complex from the platelet surface in this patient.
Reddy, Vijay S
2017-09-01
Adenoviruses are respiratory, ocular and enteric pathogens that form complex capsids, which are assembled from seven different structural proteins and composed of several core proteins that closely interact with the packaged dsDNA genome. The recent near-atomic resolution structures revealed that the interlacing continuous hexagonal network formed by the protein IX molecules is conserved among different human adenoviruses (HAdVs), but not in non-HAdVs. In this report, we propose a distinct role for the hexon protein as a "molecular mold" in enabling the formation of such hexagonal protein IX network that has been shown to preserve the stability and infectivity of HAdVs. Copyright © 2017 Elsevier Ltd. All rights reserved.
Automation technology and sense of control: a window on human agency.
Berberian, Bruno; Sarrazin, Jean-Christophe; Le Blaye, Patrick; Haggard, Patrick
2012-01-01
Previous studies have shown that the perceived times of voluntary actions and their effects are perceived as shifted towards each other, so that the interval between action and outcome seems shortened. This has been referred to as 'intentional binding' (IB). However, the generality of this effect remains unclear. Here we demonstrate that Intentional Binding also occurs in complex control situations. Using an aircraft supervision task with different autopilot settings, our results first indicated a strong relation between measures of IB and different levels of system automation. Second, measures of IB were related to explicit agency judgement in this applied setting. We discuss the implications for the underlying mechanisms, and for sense of agency in automated environments.
A Critical Role of Platelet Adhesion in the Initiation of Atherosclerotic Lesion Formation
Massberg, Steffen; Brand, Korbinian; Grüner, Sabine; Page, Sharon; Müller, Elke; Müller, Iris; Bergmeier, Wolfgang; Richter, Thomas; Lorenz, Michael; Konrad, Ildiko; Nieswandt, Bernhard; Gawaz, Meinrad
2002-01-01
The contribution of platelets to the process of atherosclerosis remains unclear. Here, we show in vivo that platelets adhere to the vascular endothelium of the carotid artery in ApoE − / − mice before the development of manifest atherosclerotic lesions. Platelet–endothelial cell interaction involved both platelet glycoprotein (GP)Ibα and GPIIb-IIIa. Platelet adhesion to the endothelium coincides with inflammatory gene expression and preceded atherosclerotic plaque invasion by leukocytes. Prolonged blockade of platelet adhesion in ApoE − / − mice profoundly reduced leukocyte accumulation in the arterial intima and attenuated atherosclerotic lesion formation in the carotid artery bifurcation, the aortic sinus, and the coronary arteries. These findings establish the platelet as a major player in initiation of the atherogenetic process. PMID:12370251
2009-10-28
CAPE CANAVERAL, Fla. - Almost twice as tall as Disney's Cinderella Castle, the Constellation Program's 327-foot-tall Ares I-X test rocket races off Launch Complex 39B at NASA's Kennedy Space Center in Florida. The rocket produces 2.96 million pounds of thrust at liftoff and reaches a speed of 100 mph in eight seconds. Liftoff of the 6-minute flight test was at 11:30 a.m. EDT Oct. 28. This was the first launch from Kennedy's pads of a vehicle other than the space shuttle since the Apollo Program's Saturn rockets were retired. The parts used to make the Ares I-X booster flew on 30 different shuttle missions ranging from STS-29 in 1989 to STS-106 in 2000. The data returned from more than 700 sensors throughout the rocket will be used to refine the design of future launch vehicles and bring NASA one step closer to reaching its exploration goals. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo courtesy of Scott Andrews
2009-10-28
CAPE CANAVERAL, Fla. - Almost twice as tall as Disney's Cinderella Castle, NASA's 327-foot-tall Ares I-X test rocket lifts off from Launch Complex 39B at NASA's Kennedy Space Center in Florida. The rocket produces 2.96 million pounds of thrust at liftoff and reaches a speed of 100 mph in eight seconds. Liftoff of the 6-minute flight test was at 11:30 a.m. EDT Oct. 28. This was the first launch from Kennedy's pads of a vehicle other than the space shuttle since the Apollo Program's Saturn rockets were retired. The parts used to make the Ares I-X booster flew on 30 different shuttle missions ranging from STS-29 in 1989 to STS-106 in 2000. The data returned from more than 700 sensors throughout the rocket will be used to refine the design of future launch vehicles and bring NASA one step closer to reaching its exploration goals. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Carl Winebarger
2009-10-28
CAPE CANAVERAL, Fla. - Almost twice as tall as Disney's Cinderella Castle, the Constellation Program's 327-foot-tall Ares I-X test rocket lifts off from Launch Complex 39B at NASA's Kennedy Space Center in Florida. The rocket produces 2.96 million pounds of thrust at liftoff and reaches a speed of 100 mph in eight seconds. Liftoff of the 6-minute flight test was at 11:30 a.m. EDT Oct. 28. This was the first launch from Kennedy's pads of a vehicle other than the space shuttle since the Apollo Program's Saturn rockets were retired. The parts used to make the Ares I-X booster flew on 30 different shuttle missions ranging from STS-29 in 1989 to STS-106 in 2000. The data returned from more than 700 sensors throughout the rocket will be used to refine the design of future launch vehicles and bring NASA one step closer to reaching its exploration goals. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Jack Pfaller
2009-10-28
CAPE CANAVERAL, Fla. - Almost twice as tall as Disney's Cinderella Castle, the Constellation Program's 327-foot-tall Ares I-X test rocket races off Launch Complex 39B at NASA's Kennedy Space Center in Florida. The rocket produces 2.96 million pounds of thrust at liftoff and reaches a speed of 100 mph in eight seconds. Liftoff of the 6-minute flight test was at 11:30 a.m. EDT Oct. 28. This was the first launch from Kennedy's pads of a vehicle other than the space shuttle since the Apollo Program's Saturn rockets were retired. The parts used to make the Ares I-X booster flew on 30 different shuttle missions ranging from STS-29 in 1989 to STS-106 in 2000. The data returned from more than 700 sensors throughout the rocket will be used to refine the design of future launch vehicles and bring NASA one step closer to reaching its exploration goals. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
2009-10-28
CAPE CANAVERAL, Fla. - Nearly twice as tall as the space shuttle, the Constellation Program's 327-foot-tall Ares I-X test rocket races off Launch Complex 39B at NASA's Kennedy Space Center in Florida. The rocket produces 2.96 million pounds of thrust at liftoff and reaches a speed of 100 mph in eight seconds. Liftoff of the 6-minute flight test was at 11:30 a.m. EDT Oct. 28. This was the first launch from Kennedy's pads of a vehicle other than the space shuttle since the Apollo Program's Saturn rockets were retired. The parts used to make the Ares I-X booster flew on 30 different shuttle missions ranging from STS-29 in 1989 to STS-106 in 2000. The data returned from more than 700 sensors throughout the rocket will be used to refine the design of future launch vehicles and bring NASA one step closer to reaching its exploration goals. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo courtesy of Scott Andrews
2009-10-28
CAPE CANAVERAL, Fla. - With more than 23 times the power output of the Hoover Dam, the Constellation Program's Ares I-X test rocket zooms off Launch Complex 39B at NASA's Kennedy Space Center in Florida. The rocket produces 2.96 million pounds of thrust at liftoff and reaches a speed of 100 mph in eight seconds. Liftoff of the 6-minute flight test was at 11:30 a.m. EDT Oct. 28. This was the first launch from Kennedy's pads of a vehicle other than the space shuttle since the Apollo Program's Saturn rockets were retired. The parts used to make the Ares I-X booster flew on 30 different shuttle missions ranging from STS-29 in 1989 to STS-106 in 2000. The data returned from more than 700 sensors throughout the rocket will be used to refine the design of future launch vehicles and bring NASA one step closer to reaching its exploration goals. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett
2009-10-28
CAPE CANAVERAL, Fla. - With more than 23 times the power output of the Hoover Dam, the Constellation Program's Ares I-X test rocket zooms off Launch Complex 39B at NASA's Kennedy Space Center in Florida. The rocket produces 2.96 million pounds of thrust at liftoff and reaches a speed of 100 mph in eight seconds. Liftoff of the 6-minute flight test was at 11:30 a.m. EDT Oct. 28. This was the first launch from Kennedy's pads of a vehicle other than the space shuttle since the Apollo Program's Saturn rockets were retired. The parts used to make the Ares I-X booster flew on 30 different shuttle missions ranging from STS-29 in 1989 to STS-106 in 2000. The data returned from more than 700 sensors throughout the rocket will be used to refine the design of future launch vehicles and bring NASA one step closer to reaching its exploration goals. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Jack Pfaller
2009-10-28
CAPE CANAVERAL, Fla. - With more than 23 times the power output of the Hoover Dam, NASA's Ares I-X test rocket zooms off Launch Complex 39B at NASA's Kennedy Space Center in Florida. The rocket produces 2.96 million pounds of thrust at liftoff and reaches a speed of 100 mph in eight seconds. Liftoff of the 6-minute flight test was at 11:30 a.m. EDT Oct. 28. This was the first launch from Kennedy's pads of a vehicle other than the space shuttle since the Apollo Program's Saturn rockets were retired. The parts used to make the Ares I-X booster flew on 30 different shuttle missions ranging from STS-29 in 1989 to STS-106 in 2000. The data returned from more than 700 sensors throughout the rocket will be used to refine the design of future launch vehicles and bring NASA one step closer to reaching its exploration goals. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Carl Winebarger
Kong, Leopold; Wilson, Ian A.; Kwong, Peter D.
2014-12-26
The crystal structure of a fully glycosylated HIV-1 gp120 core in complex with CD4 receptor and Fab 17b at 4.5-Å resolution reveals 9 of the 15 N-linked glycans of core gp120 to be partially ordered. The glycan at position Asn262 had the most extensive and well-ordered electron density, and a GlcNAc 2Man 7 was modeled. Lastly, the GlcNAc stem of this glycan is largely buried in a cleft in gp120, suggesting a role in gp120 folding and stability. Its arms interact with the stems of neighboring glycans from the oligomannose patch, which is a major target for broadly neutralizing antibodies.
Gorseta, Kristina; Borzabadi-Farahani, Ali; Moshaverinia, Alireza; Glavina, Domagoj; Lynch, Edward
2017-07-01
Whether polymerization lights can be used for heating glass ionomer cements (GICs) or glass carbomer (GCP) to improve their mechanical properties is not well established. The purpose of this in vitro study was to assess the effect of thermo-light polymerization on the flexural strength (FS) of 2 GICs (Fuji IX GP Fast, Ketac Molar) and a GCP. Specimens (n=10) were prepared in stainless steel molds (2×2×25 mm), compressed, exposed to 3 polymerization lights (500, 1000, 1200 mW/cm 2 ) for 2 cycles of 40 seconds on each side, and stored in petroleum jelly (37°C, 24 hours). Significant FS differences were detected among groups after different thermo-light polymerization regimens (F=50.926, df=11, P<.001). GCP showed the highest mean FS (∼5 times, P<.001) after thermo-light polymerization with power outputs of 1000 (127.1 ±25.8 MPa) and 1200 mW/cm 2 (117.4 ±18.5 MPa), with no significance difference between them (P=.98), compared with 500 mW/cm 2 (24.1 ±1.7 MPa). For Ketac Molar, compared with autopolymerization setting (15.5 ±3.1 MPa), a significant increase in mean FS (∼2.5 times) was only observed in specimens treated with 1200 mW/cm 2 polymerization light (P=.03). For Fuji IX GP Fast, only the light with 1000 mW/cm 2 output significantly increased the FS (98.9 ±23.4 MPa, P<.001) compared with the autopolymerization setting (34.9 ±6.4 MPa). Thermo-light polymerization accelerated the development of FS in the tested GICs, potentially protecting against saliva contamination during the first 3 to 4 minutes after mixing GIC. Thermo-light polymerization of the glass carbomer with power outputs of 1000 and 1200 mW/cm 2 also substantially increased FS. The clinical advantages of the findings should be validated by in vivo studies. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.
van der Wal, Dianne E.; Gitz, Eelo; Du, Vivian X.; Lo, Kimberly S.L.; Koekman, Cornelis A.; Versteeg, Sabine; Akkerman, Jan Willem N.
2012-01-01
Background Cold storage of platelets reduces bacterial growth and preserves their hemostatic properties better than current procedures do. However, storage at 0°C induces [14-3-3ζ-glycoprotein Ibα] association, 14-3-3ζ release from phospho-Bad, Bad activation and apoptosis. Design and Methods We investigated whether arachidonic acid, which also binds 14-3-3ζ, contributes to coldinduced apoptosis. Results Cold storage activated P38-mitogen-activated protein kinase and released arachidonic acid, which accumulated due to cold inactivation of cyclooxygenase-1/thromboxane synthase. Accumulated arachidonic acid released 14-3-3ζ from phospho-Bad and decreased the mitochondrial membrane potential, which are steps in the induction of apoptosis. Addition of arachidonic acid did the same and its depletion made platelets resistant to cold-induced apoptosis. Incubation with biotin-arachidonic acid revealed formation of an [arachidonic acid-14-3-3ζ-glycoprotein Ibα] complex. Indomethacin promoted complex formation by accumulating arachidonic acid and released 14-3-3ζ from cyclo-oxygenase-1. Arachidonic acid depletion prevented the cold-induced reduction of platelet survival in mice. Conclusions We conclude that cold storage induced apoptosis through an [arachidonic acid-14-3-3ζ-glycoprotein Ibα] complex, which released 14-3-3ζ from Bad in an arachidonic acid-dependent manner. Although arachidonic acid depletion reduced agonist-induced thromboxane A2 formation and aggregation, arachidonic acid repletion restored these functions, opening ways to reduce apoptosis during storage without compromising hemostatic functions post-transfusion. PMID:22371179
Targeting HIV-1 gp41-induced fusion and pathogenesis for anti-viral therapy.
Garg, Himanshu; Viard, Mathias; Jacobs, Amy; Blumenthal, Robert
2011-12-01
HIV gp41 is a metastable protein whose native conformation is maintained in the form of a heterodimer with gp120. The non-covalently associated gp41/gp120 complex forms a trimer on the virus surface. As gp120 engages with HIV's receptor, CD4, and coreceptor, CXCR4 or CCR5, gp41 undergoes several conformational changes resulting in fusion between the viral and cellular membranes. Several lipophilic and amphiphilic domains have been shown to be critical in that process. While the obvious function of gp41 in viral entry is well-established its role in cellular membrane fusion and the link with pathogenesis are only now beginning to appear. Recent targeting of gp41 via fusion inhibitors has revealed an important role of this protein not only in viral entry but also in bystander apoptosis and HIV pathogenesis. Studies by our group and others have shown that the phenomenon of gp41-mediated hemifusion initiates apoptosis in bystander cells and correlates with virus pathogenesis. More interestingly, recent clinical evidence suggests that gp41 mutants arising after Enfuvirtide therapy are associated with CD4 cell increase and immunological benefits. This has in turn been correlated to a decrease in bystander apoptosis in our in vitro as well as in vivo assays. Although a great deal of work has been done to unravel HIV-1 gp41-mediated fusion mechanisms, the factors that regulate gp41-mediated fusion versus hemifusion and the mechanism by which hemifusion initiates bystander apoptosis are not fully understood. Further insight into these issues will open new avenues for drug development making gp41 a critical anti-HIV target both for neutralization and virus attenuation.
Novel Small Molecules Disabling the IL-6/IL-6R/GP130 Heterohexamer Complex
2012-10-01
fluctuations over 20 ns MD simulation. The HFI unit of MDL-A showed instability in the gp130 D1-domain binding pocket, whereas the hydrophobic tail...compound containing only an HFI unit was not capable of inhibiting gp130 homodimerization. Our MDLs MD simulation studies showed consistent results...chain attached to the HFI unit which is designed to take advantage of interactions with the “additional” subpockets surrounding the MDL-A binding site
Endocrine cells in the oxyntic mucosa of the stomach in patients with irritable bowel syndrome
El-Salhy, Magdy; Gilja, Odd Helge; Gundersen, Doris; Hausken, Trygve
2014-01-01
AIM: To study the different endocrine cell types in the oxyntic mucosa of patients with irritable bowel syndrome (IBS). METHODS: Seventy-six patients with IBS were included in the study (62 females and 14 males; mean age 32 years, range 18-55 years), of which 40 also fulfilled the Rome III criteria for functional dyspepsia (FDP). Of the entire IBS cohort, 26 had diarrhea as the predominant symptom (IBS-D), 21 had a mixture of diarrhea and constipation (IBS-M), and 29 had constipation as the predominant symptom (IBS-C). Forty-three age and sex-matched healthy volunteers without any gastrointestinal complaints served as controls. The patients were asked to complete the Birmingham IBS symptom questionnaire. Both the patients and controls underwent a standard gastroscopy, during which three biopsy samples were taken from the corpus. Sections from these biopsy samples were immunostained using the avidin-biotin complex (ABC) method, for ghrelin, serotonin, somatostatin and histamine. The densities of these cell types and immunoreactivity intensities were quantified using computerized image analysis with Olympus cellSens imaging software (version 1.7). RESULTS: The densities of the ghrelin cells in the control, IBS-total, IBS-D, IBS-M and IBS-C groups were 389 (320, 771), 359 (130, 966), 966 (529, 1154), 358 (120, 966) and 126 (0, 262) cells/mm2, respectively. There was a significant difference between the tested groups (P < 0.0001). Dunn’s multiple comparison test showed that the ghrelin cell density was significantly higher in IBS-D and lower in IBS-C than in the controls (P = 0.03 and 0.0008, respectively). The ghrelin cell density in patients with both IBS and FDP was 489 (130, 966), and in those with IBS only 490 (130, 956). There was no statistical significant difference between these 2 groups of patients (P = 0.9). The immunoreactivity intensity did not differ between any of the groups (P = 0.6). The diarrhea score of the Birmingham IBS symptom questionnaire was significantly positively correlated with ghrelin cell density (r = 0.65; P < 0.0001) and significantly inversely correlated with that of constipation (r = 90.69; P < 0.0001). The densities of the serotonin cells were 63 (51, 82), 51 (25, 115), 120 (69, 128), 74 (46, 123) and 40 (0, 46) cells/mm2 in the control, IBS-total, IBS-D, IBS-M and IBS-C groups, respectively. A statistically significant difference was found between the tested groups (P < 0.0001). Posttest revealed that serotonin cell density was significantly higher in IBS-D and lower in IBS-C than in controls (P = 0.02 and 0.004, respectively), but did not differ in the IBS-total and IBS-M groups from that in controls (P = 0.5 and 0.4, respectively). The serotonin cell density in patients with both IBS and FDP was 62 (25, 115) and in those with IBS only 65 (25, 123). There was no statistically significant difference between these 2 groups of patients (P = 1). The immunoreactivity intensity of serotonin did not differ significantly between any of the groups (P = 0.0.9). The serotonin cell density was significantly positively correlated with the diarrhea score of the Birmingham IBS symptom questionnaire (r = 0.56; P < 0.0001) and significantly inversely correlated with that of constipation (r = 0.51; P < 0.0001). The densities of the somatostatin cells were 97 (72, 126), 72 (0, 206), 29 (0, 80), 46 (0, 103) and 206 (194, 314) cells/mm2 in the control, IBS-total, IBS-D, IBS-M and IBS-C groups, respectively (Figures 7 and 8). There was a statistically significant difference between the controls and the IBS subgroups (P < 0.0001). The density of somatostatin cells was significantly lower in the IBS-D and IBS-M groups but higher in IBS-C patients than in the controls (P < 0.01, P = 0.02, and P = 0.0008, respectively). The somatostatin cell density in patients with both IBS and FDP was 86 (0-194), and in those with IBS only 110 (0-206). There was no statistically significant difference between these 2 groups of patients (P = 0.6). There was no significant difference in somatostatin immunoreactivity intensity between the controls. The diarrhea score of the Birmingham IBS symptom questionnaire was inversely correlated with somatostatin cell density (r = 0.38; P = 0.0007) and was positively correlated with that of constipation (r = 0.64; P < 0.0001). CONCLUSION: The finding of abnormal endocrine cells in the oxyntic mucosa shows that the endocrine cell disturbances in IBS are not restricted to the intestine. Furthermore, it appears that ghrelin, serotonin and somatostatin in the oxyntic mucosa of the stomach may play an important role in the changing stool habits in IBS through their effects on intestinal motility. PMID:24891930
NASA Astrophysics Data System (ADS)
Chichibu, Shigefusa F.; Ishikawa, Youichi; Kominami, Hiroko; Hara, Kazuhiko
2018-02-01
The radiative performance of hexagonal boron nitride (h-BN) was assessed by the spatio-time-resolved luminescence measurements on its microcrystals (MCs) annealed in an O2 gas ambient. The MCs exhibited distinct deep ultraviolet luminescence peaks higher than 5.7 eV, although h-BN is an indirect bandgap semiconductor. The result indicates a strong interaction between the indirect excitons (iXs) and LO/TO (and LA/TA) phonons at T points of the Brillouin zone. Such phonon replicas of free iXs and a luminescence band at 4.0 eV showed negligible thermal quenching, most probably assisted by the strong excitonic effect, enhanced phonon scattering, and formation of a surface BxOy layer that prevents excitons from surface recombination by the thermal excitation. Conversely, the luminescence band between 5.1 and 5.7 eV, which seems to consist of LO/TO phonon replicas of iXs localized at a certain structural singularity that are further scattered by multiple TO phonons at K points and another two emission peaks that originate from the singularity, showed the thermal quenching. In analogy with GaN and AlGaN, cation vacancy complexes most likely act as native nonradiative recombination centers (NRCs). In the present case, vacancy complexes that contain a boron vacancy (VB), such as divacancies with a nitrogen vacancy (VN), VBVN, are certain to act as NRCs. In this instance, iXs delocalized from the singularity are likely either captured by NRCs or the origin of the 4.0 eV-band; the latter is assigned to originate from a carbon on the N site or a complex between VB and an oxygen on the N site.
Al-Sahaf, Harith; Zhang, Mengjie; Johnston, Mark
2016-01-01
In the computer vision and pattern recognition fields, image classification represents an important yet difficult task. It is a challenge to build effective computer models to replicate the remarkable ability of the human visual system, which relies on only one or a few instances to learn a completely new class or an object of a class. Recently we proposed two genetic programming (GP) methods, one-shot GP and compound-GP, that aim to evolve a program for the task of binary classification in images. The two methods are designed to use only one or a few instances per class to evolve the model. In this study, we investigate these two methods in terms of performance, robustness, and complexity of the evolved programs. We use ten data sets that vary in difficulty to evaluate these two methods. We also compare them with two other GP and six non-GP methods. The results show that one-shot GP and compound-GP outperform or achieve results comparable to competitor methods. Moreover, the features extracted by these two methods improve the performance of other classifiers with handcrafted features and those extracted by a recently developed GP-based method in most cases.
Structure-affinity relationships for the binding of actinomycin D to DNA
NASA Astrophysics Data System (ADS)
Gallego, José; Ortiz, Angel R.; de Pascual-Teresa, Beatriz; Gago, Federico
1997-03-01
Molecular models of the complexes between actinomycin D and 14 different DNA hexamers were built based on the X-ray crystal structure of the actinomycin-d(GAAGCTTC)2 complex. The DNA sequences included the canonical GpC binding step flanked by different base pairs, nonclassical binding sites such as GpG and GpT, and sites containing 2,6-diamino- purine. A good correlation was found between the intermolecular interaction energies calculated for the refined complexes and the relative preferences of actinomycin binding to standard and modified DNA. A detailed energy decomposition into van der Waals and electrostatic components for the interactions between the DNA base pairs and either the chromophore or the peptidic part of the antibiotic was performed for each complex. The resulting energy matrix was then subjected to principal component analysis, which showed that actinomycin D discriminates among different DNA sequences by an interplay of hydrogen bonding and stacking interactions. The structure-affinity relationships for this important antitumor drug are thus rationalized and may be used to advantage in the design of novel sequence-specific DNA-binding agents.
Blattner, Claudia; Lee, Jeong Hyun; Sliepen, Kwinten; Derking, Ronald; Falkowska, Emilia; de la Peña, Alba Torrents; Cupo, Albert; Julien, Jean-Philippe; van Gils, Marit; Lee, Peter S; Peng, Wenjie; Paulson, James C; Poignard, Pascal; Burton, Dennis R; Moore, John P; Sanders, Rogier W; Wilson, Ian A; Ward, Andrew B
2014-05-15
All previously characterized broadly neutralizing antibodies to the HIV-1 envelope glycoprotein (Env) target one of four major sites of vulnerability. Here, we define and structurally characterize a unique epitope on Env that is recognized by a recently discovered family of human monoclonal antibodies (PGT151-PGT158). The PGT151 epitope is comprised of residues and glycans at the interface of gp41 and gp120 within a single protomer and glycans from both subunits of a second protomer and represents a neutralizing epitope that is dependent on both gp120 and gp41. Because PGT151 binds only to properly formed, cleaved trimers, this distinctive property, and its ability to stabilize Env trimers, has enabled the successful purification of mature, cleaved Env trimers from the cell surface as a complex with PGT151. Here we compare the structural and functional properties of membrane-extracted Env trimers from several clades with those of the soluble, cleaved SOSIP gp140 trimer. Copyright © 2014 Elsevier Inc. All rights reserved.
Zoonotic Cryptosporidium Species in Animals Inhabiting Sydney Water Catchments
Zahedi, Alireza; Monis, Paul; Aucote, Sarah; King, Brendon; Paparini, Andrea; Jian, Fuchun; Yang, Rongchang; Oskam, Charlotte; Ball, Andrew; Robertson, Ian; Ryan, Una
2016-01-01
Cryptosporidium is one of the most common zoonotic waterborne parasitic diseases worldwide and represents a major public health concern of water utilities in developed nations. As animals in catchments can shed human-infectious Cryptosporidium oocysts, determining the potential role of animals in dissemination of zoonotic Cryptosporidium to drinking water sources is crucial. In the present study, a total of 952 animal faecal samples from four dominant species (kangaroos, rabbits, cattle and sheep) inhabiting Sydney’s drinking water catchments were screened for the presence of Cryptosporidium using a quantitative PCR (qPCR) and positives sequenced at multiple loci. Cryptosporidium species were detected in 3.6% (21/576) of kangaroos, 7.0% (10/142) of cattle, 2.3% (3/128) of sheep and 13.2% (14/106) of rabbit samples screened. Sequence analysis of a region of the 18S rRNA locus identified C. macropodum and C. hominis in 4 and 17 isolates from kangaroos respectively, C. hominis and C. parvum in 6 and 4 isolates respectively each from cattle, C. ubiquitum in 3 isolates from sheep and C. cuniculus in 14 isolates from rabbits. All the Cryptosporidium species identified were zoonotic species with the exception of C. macropodum. Subtyping using the 5’ half of gp60 identified C. hominis IbA10G2 (n = 12) and IdA15G1 (n = 2) in kangaroo faecal samples; C. hominis IbA10G2 (n = 4) and C. parvum IIaA18G3R1 (n = 4) in cattle faecal samples, C. ubiquitum subtype XIIa (n = 1) in sheep and C. cuniculus VbA23 (n = 9) in rabbits. Additional analysis of a subset of samples using primers targeting conserved regions of the MIC1 gene and the 3’ end of gp60 suggests that the C. hominis detected in these animals represent substantial variants that failed to amplify as expected. The significance of this finding requires further investigation but might be reflective of the ability of this C. hominis variant to infect animals. The finding of zoonotic Cryptosporidium species in these animals may have important implications for the management of drinking water catchments to minimize risk to public health. PMID:27973572
Multilocus typing of Cryptosporidium spp. and Giardia duodenalis from non-human primates in China.
Karim, Md Robiul; Zhang, Sumei; Jian, Fuchun; Li, Jiacheng; Zhou, Chunxiang; Zhang, Longxian; Sun, Mingfei; Yang, Guangyou; Zou, Fengcai; Dong, Haiju; Li, Jian; Rume, Farzana Islam; Qi, Meng; Wang, Rongjun; Ning, Changshen; Xiao, Lihua
2014-11-01
Non-human primates (NHPs) are commonly infected with Cryptosporidium spp. and Giardia duodenalis. However, molecular characterisation of these pathogens from NHPs remains scarce. In this study, 2,660 specimens from 26 NHP species in China were examined and characterised by PCR amplification of 18S rRNA, 70kDa heat shock protein (hsp70) and 60kDa glycoprotein (gp60) gene loci for Cryptosporidium; and 1,386 of the specimens by ssrRNA, triosephosphate isomerase (tpi) and glutamate dehydrogenase (gdh) gene loci for Giardia. Cryptosporidium was detected in 0.7% (19/2660) specimens of four NHP species including rhesus macaques (0.7%), cynomolgus monkeys (1.0%), slow lorises (10.0%) and Francois' leaf monkeys (6.7%), belonging to Cryptosporidium hominis (14/19) and Cryptosporidium muris (5/19). Two C. hominis gp60 subtypes, IbA12G3 and IiA17 were observed. Based on the tpi locus, G. duodenalis was identified in 2.2% (30/1,386) of specimens including 2.1% in rhesus macaques, 33.3% in Japanese macaques, 16.7% in Assam macaques, 0.7% in white-headed langurs, 1.6% in cynomolgus monkeys and 16.7% in olive baboons. Sequence analysis of the three targets indicated that all of the Giardia-positive specimens belonged to the zoonotic assemblage B. Highest sequence polymorphism was observed at the tpi locus, including 11 subtypes: three known and eight new ones. Phylogenetic analysis of the subtypes showed that most of them were close to the so-called subtype BIV. Intragenotypic variations at the gdh locus revealed six types of sequences (three known and three new), all of which belonged to so-called subtype BIV. Three specimens had co-infection with C. hominis (IbA12G3) and G. duodenalis (BIV). The presence of zoonotic genotypes and subtypes of Cryptosporidium spp. and G. duodenalis in NHPs suggests that these animals can potentially contribute to the transmission of human cryptosporidiosis and giardiasis. Copyright © 2014 Australian Society for Parasitology Inc. All rights reserved.
Wind Tunnel Investigation of Ground Wind Loads for Ares Launch Vehicle
NASA Technical Reports Server (NTRS)
Keller, Donald F.; Ivanco, Thomas G.
2010-01-01
A three year program was conducted at the NASA Langley Research Center (LaRC) Aeroelasticity Branch (AB) and Transonic Dynamics Tunnel (TDT) with the primary objective to acquire scaled steady and dynamic ground-wind loads (GWL) wind-tunnel data for rollout, on-pad stay, and on-pad launch configurations for the Ares I-X Flight Test Vehicle (FTV). The experimental effort was conducted to obtain an understanding of the coupling of aerodynamic and structural characteristics that can result in large sustained wind-induced oscillations (WIO) on such a tall and slender launch vehicle and to generate a unique database for development and evaluation of analytical methods for predicting steady and dynamic GWL, especially those caused by vortex shedding, and resulting in significant WIO. This paper summarizes the wind-tunnel test program that employed two dynamically-aeroelastically scaled GWL models based on the Ares I-X Flight Test Vehicle. The first model tested, the GWL Checkout Model (CM), was a relatively simple model with a secondary objective of restoration and development of processes and methods for design, fabrication, testing, and data analysis of a representative ground wind loads model. In addition, parametric variations in surface roughness, Reynolds number, and protuberances (on/off) were investigated to determine effects on GWL characteristics. The second windtunnel model, the Ares I-X GWL Model, was significantly more complex and representative of the Ares I-X FTV and included the addition of simplified rigid geometrically-scaled models of the Kennedy Space Center (KSC) Mobile Launch Platform (MLP) and Launch Complex 39B primary structures. Steady and dynamic base bending moment as well as model response and steady and unsteady pressure data was acquired during the testing of both models. During wind-tunnel testing of each model, flow conditions (speed and azimuth) where significant WIO occurred, were identified and thoroughly investigated. Scaled data from the Ares I-X GWL model test was used in the determination of worst-case loads for the analysis of Ares I-X FTV design wind conditions. Finally, this paper includes a brief discussion of the limited full-scale GWL data acquired during the rollout and on-pad stay of the Ares I-X FTV that was launched from KSC on October 28, 2009.
Kroy, Daniela C; Hebing, Lisa; Sander, Leif E; Gassler, Nikolaus; Erschfeld, Stephanie; Sackett, Sara; Galm, Oliver; Trautwein, Christian; Streetz, Konrad L
2012-01-01
Bone marrow transplantation (BMT) is a complex process regulated by different cytokines and growth factors. The pleiotropic cytokine IL-6 (Interleukin-6) and related cytokines of the same family acting on the common signal transducer gp130 are known to play a key role in bone marrow (BM) engraftment. In contrast, the exact signalling events that control IL-6/gp130-driven haematopoietic stem cell development during BMT remain unresolved. Conditional gp130 knockout and knockin mice were used to delete gp130 expression (gp130(ΔMx)), or to selectively disrupt gp130-dependent Ras (gp130(ΔMxRas)) or STAT signalling (gp130(ΔMxSTAT)) in BM cells. BM derived from the respective strains was transplanted into irradiated wildtype hosts and repopulation of various haematopoietic lineages was monitored by flow cytometry. BM derived from gp130 deficient donor mice (gp130(ΔMx)) displayed a delayed engraftment, as evidenced by reduced total white blood cells (WBC), marked thrombocytopenia and anaemia in the early phase after BMT. Lineage analysis unravelled a restricted development of CD4(+) and CD8(+) T-cells, CD19(+) B-cells and CD11b(+) myeloid cells after transplantation of gp130-deficient BM grafts. To further delineate the two major gp130-induced signalling cascades, Ras-MAPK and STAT1/3-signalling respectively, we used gp130(ΔMxRas) and gp130(ΔMxSTAT) donor BM. BMT of gp130(ΔMxSTAT) cells significantly impaired engraftment of CD4(+), CD8(+), CD19(+) and CD11b(+) cells, whereas gp130(ΔMxRas) BM displayed a selective impairment in early thrombopoiesis. Importantly, gp130-STAT1/3 signalling deficiency in BM grafts severely impaired survival of transplanted mice, thus demonstrating a pivotal role for this pathway in BM graft survival and function. Our data unravel a vital function of IL-6/gp130-STAT1/3 signals for BM engraftment and haematopoiesis, as well as for host survival after transplantation. STAT1/3 and ras-dependent pathways thereby exert distinct functions on individual bone-marrow-lineages.
Osheroff, Neil
2006-10-01
Smallpox is a serious and highly contagious disease that is caused by the variola virus. It is one of the most severe infectious human diseases known, with mortality rates as high as 30%. A successful worldwide vaccination program led to the eradication of smallpox in 1980. However, the high transmission rate of variola virus, coupled with the deadly nature of smallpox, makes this virus a potentially devastating weapon for bioterrorism. Currently, there is no specific treatment for smallpox. However, a recent article on the structure of a variola topoisomerase IB-DNA complex provides an intriguing starting point for the rational design of drugs with potential activity against smallpox.
Automation Technology and Sense of Control: A Window on Human Agency
Berberian, Bruno; Sarrazin, Jean-Christophe; Le Blaye, Patrick; Haggard, Patrick
2012-01-01
Previous studies have shown that the perceived times of voluntary actions and their effects are perceived as shifted towards each other, so that the interval between action and outcome seems shortened. This has been referred to as ‘intentional binding’ (IB). However, the generality of this effect remains unclear. Here we demonstrate that Intentional Binding also occurs in complex control situations. Using an aircraft supervision task with different autopilot settings, our results first indicated a strong relation between measures of IB and different levels of system automation. Second, measures of IB were related to explicit agency judgement in this applied setting. We discuss the implications for the underlying mechanisms, and for sense of agency in automated environments. PMID:22479528
Xu, Yuqun; Miyakawa, Takuya; Nakamura, Hidemitsu; Nakamura, Akira; Imamura, Yusaku; Asami, Tadao; Tanokura, Masaru
2016-08-10
The perception of two plant germination inducers, karrikins and strigolactones, are mediated by the proteins KAI2 and D14. Recently, KAI2-type proteins from parasitic weeds, which are possibly related to seed germination induced by strigolactone, have been classified into three clades characterized by different responses to karrikin/strigolactone. Here we characterized a karrikin-binding protein in Striga (ShKAI2iB) that belongs to intermediate-evolving KAI2 and provided the structural bases for its karrikin-binding specificity. Binding assays showed that ShKAI2iB bound karrikins but not strigolactone, differing from other KAI2 and D14. The crystal structures of ShKAI2iB and ShKAI2iB-karrikin complex revealed obvious structural differences in a helix located at the entry of its ligand-binding cavity. This results in a smaller closed pocket, which is also the major cause of ShKAI2iB's specificity of binding karrikin. Our structural study also revealed that a few non-conserved amino acids led to the distinct ligand-binding profile of ShKAI2iB, suggesting that the evolution of KAI2 resulted in its diverse functions.
The communication in industrialised building system (IBS) construction project: Virtual environment
NASA Astrophysics Data System (ADS)
Pozin, Mohd Affendi Ahmad; Nawi, Mohd Nasrun Mohd
2017-10-01
Large portion of numbers team organization in the IBS construction sector is known are being fragmented. That is contributed from a segregation of construction activity thus create team working in virtually. Virtual team are the nature when teams are working in distributed area, across culture and time. Therefore, teams can be respond to the task without relocating to the site project and settle down a problem through information and communication technology (ICT). The emergence of virtual team are carry out by advancements in communication technologies as a medium to improve project team communication in project delivery process on IBS construction. Based on literature review from previous study and data collected from interviewing, this paper aim to identified communication challenges among project team members according to current project development practices in IBS construction project. Hence, in attempt to develop effective communication through the advantages of virtual team approach for IBS construction project. In order to ensure the data is gathered comprehensively and accurately, the data was collected from project managers by using semi structured interview method. It was found that virtual team approach could be enable competitive challenges on complexity in the construction project management process.
A Review of Microbiota and Irritable Bowel Syndrome: Future in Therapies.
Rodiño-Janeiro, Bruno K; Vicario, María; Alonso-Cotoner, Carmen; Pascua-García, Roberto; Santos, Javier
2018-03-01
Irritable bowel syndrome (IBS), one of the most frequent digestive disorders, is characterized by chronic and recurrent abdominal pain and altered bowel habit. The origin seems to be multifactorial and is still not well defined for the different subtypes. Genetic, epigenetic and sex-related modifications of the functioning of the nervous and immune-endocrine supersystems and regulation of brain-gut physiology and bile acid production and absorption are certainly involved. Acquired predisposition may act in conjunction with infectious, toxic, dietary and life event-related factors to enhance epithelial permeability and elicit mucosal microinflammation, immune activation and dysbiosis. Notably, strong evidence supports the role of bacterial, viral and parasitic infections in triggering IBS, and targeting microbiota seems promising in view of the positive response to microbiota-related therapies in some patients. However, the lack of highly predictive diagnostic biomarkers and the complexity and heterogeneity of IBS patients make management difficult and unsatisfactory in many cases, reducing patient health-related quality of life and increasing the sanitary burden. This article reviews specific alterations and interventions targeting the gut microbiota in IBS, including prebiotics, probiotics, synbiotics, non-absorbable antibiotics, diets, fecal transplantation and other potential future approaches useful for the diagnosis, prevention and treatment of IBS.
Sato, Katsuhiko; Kodama, Daisuke; Naka, Yukihisa; Anzai, Jun-ichi
2006-12-01
A layer-by-layer assembly composed of avidin and 2-iminobiotin-labeled poly(ethyleneimine) (ib-PEI) was prepared on the surface of a platinum (Pt) film-coated quartz resonator, and an electrochemically induced disintegration of the avidin-ib-PEI assembly was studied using a quartz crystal microbalance. The resonance frequency of a five-bilayer (avidin-ib-PEI)5 film-coated quartz resonator was increased upon application of an electric potential to the Pt layer of the quartz resonator, suggesting that the mass on the quartz resonator was decreased as a result of disintegration of the (avidin-ib-PEI)5 film, due to a pH change in the vicinity of the surface of the Pt-coated quartz resonator. It may be that the (avidin-ib-PEI)5 film assembly was decomposed by acidification of the local pH on the surface of the Pt layer, which in turn was induced through electrolysis of water on Pt, because ib-PEI forms complexes with avidin only in basic media. In pH 9 solution, the (avidin-ib-PEI)5 film was decomposed under the influence of an applied potential of 0.6-1.0 V versus Ag/AgCl. The (avidin-ib-PEI)5 film was decomposed almost completely within a minute in a low concentration buffer (1 mM, pH 9), while the decomposition was slower in 10 and 100 mM buffer solutions at the same pH. The decomposition of the assembly was rapid when the electrode potential was applied in pH 9 solutions, while the response was relatively slow in pH 10 and 11 solutions. All the results are rationalized on the basis of an electrochemically induced acidification of the local environment around the (avidin-ib-PEI)5 film on the Pt layer.
dela Peña, Aileen; Leclercq, Isabelle A; Williams, Jacqueline; Farrell, Geoffrey C
2007-02-01
Hepatic oxidative stress is a key feature of metabolic forms of steatohepatitis, but the sources of pro-oxidants are unclear. The NADPH oxidase complex is critical for ROS generation in inflammatory cells; loss of any one component (e.g., gp91phox) renders NADPH oxidase inactive. We tested whether activated inflammatory cells contribute to oxidant stress in steatohepatitis. gp91phox-/- and wildtype (wt) mice were fed a methionine and choline-deficient (MCD) diet. Serum ALT, hepatic triglycerides, histopathology, lipid peroxidation, activation of NF-kappaB, expression of NF-kappaB-regulated genes and macrophage chemokines were measured. After 10 days of MCD dietary feeding, gp91phox-/- and wt mice displayed equivalent hepatocellular injury. After 8 weeks, there were fewer activated macrophages in livers of gp91phox-/- mice than controls, despite similar mRNA levels for MCP and MIP chemokines, but fibrosis was similar. NF-kappaB activation and increased expression of ICAM-1, TNF-alpha and COX-2 mRNA were evident in both genotypes, but in gp91phox-/- mice, expression of these genes was confined to hepatocytes. A functional NADPH oxidase complex does not contribute importantly to oxidative stress in this model and therefore is not obligatory for induction or perpetuation of dietary steatohepatitis.
Gastroparesis Updates on Pathogenesis and Management
Liu, Nanlong; Abell, Thomas
2017-01-01
Gastroparesis (Gp) is a chronic disease that presents with clinical symptoms of early satiety, bloating, nausea, vomiting, and abdominal pain. Along with these symptoms, an objective finding of delayed gastric emptying, along with a documented absence of gastric outlet obstruction, are required for diagnosis. This article focuses on updates in the pathogenesis and management of Gp. Recent studies on full thickness biopsies of Gp patients have shed light on the complex interactions of the central, autonomic, and enteric nervous systems, which all play key roles in maintaining normal gut motility. The management of Gp has evolved beyond prokinetics and antiemetics with the use of gastric electrical stimulators (GES). In addition, this review aims to introduce the concept of gastroparesis-like syndrome (GLS). GLS helps groups of patients who have the cardinal symptoms of Gp but have a normal or rapid emptying test. Recent tests have shown that patients with Gp and GLS have similar pathophysiology, benefit greatly from GES placement, and likely should be treated in a similar manner. PMID:28535580
Domicevica, Laura; Koldsø, Heidi; Biggin, Philip C
2018-03-01
P-glycoprotein (P-gp) can transport a wide range of very different hydrophobic organic molecules across the membrane. Its ability to extrude molecules from the cell creates delivery problems for drugs that target proteins in the central nervous system (CNS) and also causes drug-resistance in many forms of cancer. Whether a drug will be susceptible to export by P-gp is difficult to predict and currently this is usually assessed with empirical and/or animal models. Thus, there is a need to better understand how P-gp works at the molecular level in order to fulfil the 3Rs: Refinement, reduction and replacement of animals in research. As structural information increasingly becomes available, our understanding at the molecular level improves. Proteins like P-gp are however very dynamic entities and thus one of the most appropriate ways to study them is with molecular dynamics simulations, especially as this can capture the influence of the surrounding environment. Recent parameterization developments have meant that it is now possible to simulate lipid bilayers that more closely resemble in vivo membranes in terms of their composition. In this report we construct a complex lipid bilayer that mimics the composition of brain epithelial cells and examine the interactions of it with P-gp. We find that the negatively charged phosphatidylserine lipids in the inner leaflet of the membrane tend to form an annulus around P-gp. We also observed the interaction of cholesterol with three distinct areas of the P-gp. Potential of mean force (PMF) calculations suggest that a crevice between transmembrane helices 10 and 12 has particularly favourable interaction energy for cholesterol. Copyright © 2018 Elsevier Inc. All rights reserved.
Domicevica, Laura; Koldsø, Heidi; Biggin, Philip C
2017-09-02
P-glycoprotein (P-gp) can transport a wide range of very different hydrophobic organic molecules across the membrane. Its ability to extrude molecules from the cell creates delivery problems for drugs that target proteins in the central nervous system (CNS) and also causes drug-resistance in many forms of cancer. Whether a drug will be susceptible to export by P-gp is difficult to predict and currently this is usually assessed with empirical and/or animal models. Thus, there is a need to better understand how P-gp works at the molecular level in order to fulfil the 3Rs: Refinement, reduction and replacement of animals in research. As structural information increasingly becomes available, our understanding at the molecular level improves. Proteins like P-gp are however very dynamic entities and thus one of the most appropriate ways to study them is with molecular dynamics simulations, especially as this can capture the influence of the surrounding environment. Recent parameterization developments have meant that it is now possible to simulate lipid bilayers that more closely resemble in vivo membranes in terms of their composition. In this report we construct a complex lipid bilayer that mimics the composition of brain epithelial cells and examine the interactions of it with P-gp. We find that the negatively charged phosphatidylserine lipids in the inner leaflet of the membrane tend to form an annulus around P-gp. We also observed the interaction of cholesterol with three distinct areas of the P-gp. Potential of mean force (PMF) calculations suggest that a crevice between transmembrane helices 10 and 12 has particularly favourable interaction energy for cholesterol. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
Making sense of change: patients' views of diabetes and GP-led integrated diabetes care.
Burridge, Letitia H; Foster, Michele M; Donald, Maria; Zhang, Jianzhen; Russell, Anthony W; Jackson, Claire L
2016-02-01
Health system reform is directed towards better management of diabetes. However, change can be difficult, and patients' perspectives are a key aspect of implementing change. This study investigated patients' perceptions and experiences of type 2 diabetes (T2DM), self-care and engagement with GP-led integrated diabetes care. Qualitative interviews were conducted with purposively selected patients with T2DM following their initial medical appointment in the new model of care. Normalization process theory was used to orientate the thematic analysis, to explain the work of implementing change. Two specialist GP-based complex diabetes services in primary care in Brisbane, Australia. Intervention group patients (n = 30) in a randomized controlled trial to evaluate a model of GP-led integrated care for complex T2DM. Participants' experiences and perceptions of diabetes management and a GP-led model of care. Three themes were identified: sensibility of change, 'diabetic life' and diabetes care alliance. The imperative of change made sense, but some participants experienced dissonance between this rational view and their lived reality. Diabetes invaded life, revealing incongruities between participants' values and living with diabetes. They appreciated a flexible and personalized approach to care. Participants responded to advice in ways that seemed rational within the complexities of their life context. Their diabetes partnerships with health professionals coupled providers' biomedical expertise with patients' contextual expertise. Learning to manage relationships with various health professionals adds to patients' diabetes-related work. Providers need to adopt a flexible, interactive approach and foster trust, to enable better diabetes care. © 2015 John Wiley & Sons Ltd.
Structure of a Complex Phosphoglycan Epitope from gp72 of Trypanosoma cruzi *
Allen, Simon; Richardson, Julia M.; Mehlert, Angela; Ferguson, Michael A. J.
2013-01-01
The parasitic protozoan organism Trypanosoma cruzi is the causative agent of Chagas disease. The insect vector-dwelling epimastigote form of the organism expresses a low abundance glycoprotein associated with the flagellum adhesion zone, called gp72. The gp72 glycoprotein was first identified with an anti-carbohydrate IgG3 monoclonal antibody called WIC29.26 and has been shown to have an unusual sugar composition. Here, we describe a new way to isolate the WIC29.26 carbohydrate epitope of gp72. Using 1H NMR and mass spectrometry before and after derivatization, we provide an almost complete primary chemical structure for the epitope, which is that of a complex phosphosaccharide: Galfβ1–4Rhapα1–2Fucpα1-4(Galpβ1–3)(Galpα1–2)Xylpβ1–4Xylpβ1–3(Xylpβ1–2Galpα1-4(Galpβ1–3)(Rhapα1–2)Fucpα1–4)GlcNAcp, with phosphate attached to one or other of the two Galp terminal residues and in which all residues are of the d-absolute configuration, except for fucose and rhamnose which are l. Combined with previous data (Haynes, P. A., Ferguson, M. A., and Cross, G. A. (1996) Glycobiology 6, 869–878), we postulate that this complex structure and its variants lacking one or more residues are linked to Thr and Ser residues in gp72 via a phosphodiester linkage (GlcNAcpα1-P-Thr/Ser) and that these units may form phosphosaccharide repeats through GlcNAcpα1-P-Galp linkages. The gp72 glycoprotein is associated with the flagellum adhesion zone on the parasite surface, and its ligation has been implicated in inhibiting parasite differentiation from the epimastigote to the metacyclic trypomastigote stage. The detailed structure of the unique phosphosaccharide component of gp72 reported here provides a template for future biosynthetic and functional studies. PMID:23436655
Structure and Function Study of Phi29 DNA packaging motor
NASA Astrophysics Data System (ADS)
Fang, Huaming
A powerful nanomotor is employed by the tailed dsDNA virus to package the genome into a preformed protein shell during the process of replication. The bacteriophage phi29 is an excellent model for investigating the viral DNA packaging mechanism. The phi29 DNA packaging motor is composed of three ring structures: the dodecameric connector ring, the hexameric pRNA ring and the hexameric ATPase gp16 ring. The connector is the central hub for the DNA to enter and to exit. There are four positively charged lysine rings scattered inside the highly negatively charged connector channel. It is speculated that these positive charged lysine rings may play active roles during DNA packaging in many models. To test this prevalent view, the basic lysine residues were mutated to neutral alanines and the pH environment was altered. Amazingly, the results were beyond expectation. Neither the DNA translocation nor the one-way traffic property of the channel were measurably influenced by the alteration of the charge of lysine residues when the basic lysine residues mutated to neutral alanines or the pH environment changed to acid or basic. The ATPase or the terminase is the central part of the viral DNA packaging motor. The phi29 ATPase is highly hydrophobic and tends to aggregate in solution. A green fluorescent protein tag (eGFP) fused to the N-terminus of gp16 enhanced its solubility and stability. The eGFP-gp16 showed similar activity to wild type gp16 and was easily detected by fluorescent instruments. The interaction between eGFP-gp16 and DNA in the various conditions were investigated by electrophoretic mobility shift assay, FRET and sucrose gradient. gamma-S-ATP dramatically increased gp16 binding affinity to DNA and ATP, ADP, phosphate could release gp16 from gp16-DNA-gamma-S-ATP complex. The sliding of gp16 out of the gp16-DNA-gamma-S-ATP complex could be blocked by addition of Steptavidin to ends of dsDNA which is conjugated with biotins. Also, we found that six eGFP-gp16 molecules were required to bind to one short dsDNA molecule. The inhibitive curve of Walker B mutant gp16 analyzed by binomial distribution model showed that one inactive mutant gp16 in the gp16 ring could block the function of the motor and the stoichiometry of gp16 was six. These findings facilitate our understanding of the molecular mechanism of viral DNA packaging: a novel viral DNA packaging model "push through a one-way valve" was proposed. In this model, the connector functioned as a valve to allow DNA to enter but prevented it from sliding out during DNA packaging; the six subunits in the gp16 ring acted sequentially to push DNA into the connector channel. ATP binding of gp16 induced a conformation change with a high affinity for dsDNA. Then, the ATP was hydrolyzed which resulted in the movement of subdomains in this individual gp16 subunit and DNA was pushed forward, followed by the double helix of dsDNA being brought forward to the adjacent subunit in the gp16 ring. The elucidation of the viral DNA packaging mechanism holds great potential for developing artificial motors for delivering drugs and other molecular cargos.
Chan, Vera S. F.; Chung, Nancy P. Y.; Wang, Shu-Rong; Li, Zhongye; Ma, Jing; Lin, Chia-Wei; Hsieh, Ya-Ju; Chang, Kao-Ping; Kung, Sui-Sum; Wu, Yi-Chia; Chu, Cheng-Wei; Tai, Hsiao-Ting; Gao, George F.; Zheng, Bojian; Yokoyama, Kazunari K.; Austyn, Jonathan M.; Lin, Chen-Lung S.
2013-01-01
During disease progression to AIDS, HIV-1 infected individuals become increasingly immunosuppressed and susceptible to opportunistic infections. It has also been demonstrated that multiple subsets of dendritic cells (DC), including DC-SIGN(+) cells, become significantly depleted in the blood and lymphoid tissues of AIDS patients, which may contribute to the failure in initiating effective host immune responses. The mechanism for DC depletion, however, is unclear. It is also known that vast quantities of viral envelope protein gp120 are shed from maturing HIV-1 virions and form circulating immune complexes in the serum of HIV-1-infected individuals, but the pathological role of gp120 in HIV-1 pathogenesis remains elusive. Here we describe a previously unrecognized mechanism of DC death in chronic HIV-1 infection, in which ligation of DC-SIGN by gp120 sensitizes DC to undergo accelerated apoptosis in response to a variety of activation stimuli. The cultured monocyte-derived DC and also freshly-isolated DC-SIGN(+) blood DC that were exposed to either cross-linked recombinant gp120 or immune-complex gp120 in HIV(+) serum underwent considerable apoptosis after CD40 ligation or exposure to bacterial lipopolysaccharide (LPS) or pro-inflammatory cytokines such as TNFα and IL-1β. Furthermore, circulating DC-SIGN(+) DC that were isolated directly from HIV-1(+) individuals had actually been pre-sensitized by serum gp120 for activation-induced exorbitant apoptosis. In all cases the DC apoptosis was substantially inhibited by DC-SIGN blockade. Finally, we showed that accelerated DC apoptosis was a direct consequence of excessive activation of the pro-apoptotic molecule ASK-1 and transfection of siRNA against ASK-1 significantly prevented the activation-induced excessive DC death. Our study discloses a previously unknown mechanism of immune modulation by envelope protein gp120, provides new insights into HIV immunopathogenesis, and suggests potential therapeutic approaches to prevent DC depletion in chronic HIV infection. PMID:23382671
Isnard, Amandine; Christian, Jan G.; Kodiha, Mohamed; Stochaj, Ursula; McMaster, W. Robert; Olivier, Martin
2015-01-01
The protease GP63 is an important virulence factor of Leishmania parasites. We previously showed that GP63 reaches the perinuclear area of host macrophages and that it directly modifies nuclear translocation of the transcription factors NF-κB and AP-1. Here we describe for the first time, using molecular biology and in-depth proteomic analyses, that GP63 alters the host macrophage nuclear envelope, and impacts on nuclear processes. Our results suggest that GP63 does not appear to use a classical nuclear localization signal common between Leishmania species for import, but degrades nucleoporins, and is responsible for nuclear transport alterations. In the nucleoplasm, GP63 activity accounts for the degradation and mislocalization of proteins involved amongst others in gene expression and in translation. Collectively, our data indicates that Leishmania infection strongly affects nuclear physiology, suggesting that targeting of nuclear physiology may be a strategy beneficial for virulent Leishmania parasites. PMID:25826301
Isolation of potent neutralizing antibodies from a survivor of the 2014 Ebola virus outbreak.
Bornholdt, Zachary A; Turner, Hannah L; Murin, Charles D; Li, Wen; Sok, Devin; Souders, Colby A; Piper, Ashley E; Goff, Arthur; Shamblin, Joshua D; Wollen, Suzanne E; Sprague, Thomas R; Fusco, Marnie L; Pommert, Kathleen B J; Cavacini, Lisa A; Smith, Heidi L; Klempner, Mark; Reimann, Keith A; Krauland, Eric; Gerngross, Tillman U; Wittrup, Karl D; Saphire, Erica Ollmann; Burton, Dennis R; Glass, Pamela J; Ward, Andrew B; Walker, Laura M
2016-03-04
Antibodies targeting the Ebola virus surface glycoprotein (EBOV GP) are implicated in protection against lethal disease, but the characteristics of the human antibody response to EBOV GP remain poorly understood. We isolated and characterized 349 GP-specific monoclonal antibodies (mAbs) from the peripheral B cells of a convalescent donor who survived the 2014 EBOV Zaire outbreak. Remarkably, 77% of the mAbs neutralize live EBOV, and several mAbs exhibit unprecedented potency. Structures of selected mAbs in complex with GP reveal a site of vulnerability located in the GP stalk region proximal to the viral membrane. Neutralizing antibodies targeting this site show potent therapeutic efficacy against lethal EBOV challenge in mice. The results provide a framework for the design of new EBOV vaccine candidates and immunotherapies. Copyright © 2016, American Association for the Advancement of Science.
McEneny-King, Alanna; Edginton, Andrea N; Rao, Praveen P N
2015-01-15
The anti-Alzheimer's agent donepezil is known to bind to the hepatic enzyme CYP3A4, but its relationship with the efflux transporter P-glycoprotein (P-gp) is not as well elucidated. We conducted in vitro inhibition studies of donepezil using human recombinant CYP3A4 and P-gp. These studies show that donepezil is a weak inhibitor of CYP3A4 (IC50=54.68±1.00μM) whereas the reference agent ketoconazole exhibited potent inhibition (CYP3A4 IC50=0.20±0.01μM). P-gp inhibition studies indicate that donepezil exhibits better inhibition relative to CYP3A4 (P-gp EC50=34.85±4.63μM) although it was less potent compared to ketoconazole (P-gp EC50=9.74±1.23μM). At higher concentrations, donepezil exhibited significant inhibition of CYP3A4 (69%, 84% and 87% inhibition at 100, 250 and 500μM, respectively). This indicates its potential to cause drug-drug interactions with other CYP3A4 substrates upon co-administration; however, this scenario is unlikely in vivo due to the low therapeutic concentrations of donepezil. Similarly, donepezil co-administration with P-gp substrates or inhibitors is unlikely to result in beneficial or adverse drug interactions. The molecular docking studies show that the 5,6-dimethoxyindan-1-one moiety of donepezil was oriented closer to the heme center in CYP3A4 whereas in the P-gp binding site, the protonated benzylpiperidine pharmacophore of donepezil played a major role in its binding ability. Energy parameters indicate that donepezil complex with both CYP3A4 and P-gp was less stable (CDOCKER energies=-15.05 and -4.91kcal/mol, respectively) compared to the ketoconazole-CYP3A4 and P-gp complex (CDOCKER energies=-41.89 and -20.03kcal/mol, respectively). Copyright © 2014 Elsevier Ltd. All rights reserved.
2009-10-28
CAPE CANAVERAL, Fla. - Almost twice as tall as Disney's Cinderella Castle, the Constellation Program's 327-foot-tall Ares I-X test rocket races off Launch Complex 39B at NASA's Kennedy Space Center in Florida. The rocket produces 2.96 million pounds of thrust at liftoff and reaches a speed of 100 mph in eight seconds. Liftoff of the 6-minute flight test was at 11:30 a.m. EDT Oct. 28. This was the first launch from Kennedy's pads of a vehicle other than the space shuttle since the Apollo Program's Saturn rockets were retired. The parts used to make the Ares I-X booster flew on 30 different shuttle missions ranging from STS-29 in 1989 to STS-106 in 2000. The data returned from more than 700 sensors throughout the rocket will be used to refine the design of future launch vehicles and bring NASA one step closer to reaching its exploration goals. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Sandra Joseph and Kevin O'Connell
2009-10-28
CAPE CANAVERAL, Fla. - Almost twice as tall as Disney's Cinderella Castle, the Constellation Program's 327-foot-tall Ares I-X test rocket lifts off from Launch Complex 39B at NASA's Kennedy Space Center in Florida. The rocket produces 2.96 million pounds of thrust at liftoff and reaches a speed of 100 mph in eight seconds. Liftoff of the 6-minute flight test was at 11:30 a.m. EDT Oct. 28. This was the first launch from Kennedy's pads of a vehicle other than the space shuttle since the Apollo Program's Saturn rockets were retired. The parts used to make the Ares I-X booster flew on 30 different shuttle missions ranging from STS-29 in 1989 to STS-106 in 2000. The data returned from more than 700 sensors throughout the rocket will be used to refine the design of future launch vehicles and bring NASA one step closer to reaching its exploration goals. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo courtesy of Scott Andrews, Canon
2009-10-28
CAPE CANAVERAL, Fla. - About the length of eight school buses stacked end to end, the Constellation Program's 327-foot-tall Ares I-X test rocket races off Launch Complex 39B at NASA's Kennedy Space Center in Florida. The rocket produces 2.96 million pounds of thrust at liftoff and reaches a speed of 100 mph in eight seconds. Liftoff of the 6-minute flight test was at 11:30 a.m. EDT Oct. 28. This was the first launch from Kennedy's pads of a vehicle other than the space shuttle since the Apollo Program's Saturn rockets were retired. The parts used to make the Ares I-X booster flew on 30 different shuttle missions ranging from STS-29 in 1989 to STS-106 in 2000. The data returned from more than 700 sensors throughout the rocket will be used to refine the design of future launch vehicles and bring NASA one step closer to reaching its exploration goals. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo courtesy of Scott Andrews
2009-10-28
CAPE CANAVERAL, Fla. - With more than 23 times the power output of the Hoover Dam, the Constellation Program's Ares I-X test rocket zooms off Launch Complex 39B at NASA's Kennedy Space Center in Florida. The rocket produces 2.96 million pounds of thrust at liftoff and reaches a speed of 100 mph in eight seconds. Liftoff of the 6-minute flight test was at 11:30 a.m. EDT Oct. 28. This was the first launch from Kennedy's pads of a vehicle other than the space shuttle since the Apollo Program's Saturn rockets were retired. The parts used to make the Ares I-X booster flew on 30 different shuttle missions ranging from STS-29 in 1989 to STS-106 in 2000. The data returned from more than 700 sensors throughout the rocket will be used to refine the design of future launch vehicles and bring NASA one step closer to reaching its exploration goals. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo courtesy of Scott Andrews, Canon
Tap, Julien; Derrien, Muriel; Törnblom, Hans; Brazeilles, Rémi; Cools-Portier, Stéphanie; Doré, Joël; Störsrud, Stine; Le Nevé, Boris; Öhman, Lena; Simrén, Magnus
2017-01-01
We have limited knowledge about the association between the composition of the intestinal microbiota and clinical features of irritable bowel syndrome (IBS). We collected information on the fecal and mucosa-associated microbiota of patients with IBS and evaluated whether these were associated with symptoms. We collected fecal and mucosal samples from adult patients who met the Rome III criteria for IBS at a secondary/tertiary care outpatient clinics in Sweden, as well as from healthy subjects. The exploratory set comprised 149 subjects (110 with IBS and 39 healthy subjects); 232 fecal samples and 59 mucosal biopsy samples were collected and analyzed by 16S ribosomal RNA targeted pyrosequencing. The validation set comprised 46 subjects (29 with IBS and 17 healthy subjects); 46 fecal samples, but no mucosal samples, were collected and analyzed. For each subject, we measured exhaled H 2 and CH 4 , oro-anal transit time, and the severity of psychological and gastrointestinal symptoms. Fecal methanogens were measured by quantitative polymerase chain reaction. Numerical ecology analyses and a machine learning procedure were used to analyze the data. Fecal microbiota showed covariation with mucosal adherent microbiota. By using classic approaches, we found no differences in fecal microbiota abundance or composition between patients with IBS vs healthy patients. A machine learning procedure, a computational statistical technique, allowed us to reduce the 16S ribosomal RNA data complexity into a microbial signature for severe IBS, consisting of 90 bacterial operational taxonomic units. We confirmed the robustness of the intestinal microbial signature for severe IBS in the validation set. The signature was able to discriminate between patients with severe symptoms, patients with mild/moderate symptoms, and healthy subjects. By using this intestinal microbiota signature, we found IBS symptom severity to be associated negatively with microbial richness, exhaled CH 4 , presence of methanogens, and enterotypes enriched with Clostridiales or Prevotella species. This microbiota signature could not be explained by differences in diet or use of medications. In analyzing fecal and mucosal microbiota from patients with IBS and healthy individuals, we identified an intestinal microbiota profile that is associated with the severity of IBS symptoms. NCT01252550. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.
Geographic profiling applied to testing models of bumble-bee foraging.
Raine, Nigel E; Rossmo, D Kim; Le Comber, Steven C
2009-03-06
Geographic profiling (GP) was originally developed as a statistical tool to help police forces prioritize lists of suspects in investigations of serial crimes. GP uses the location of related crime sites to make inferences about where the offender is most likely to live, and has been extremely successful in criminology. Here, we show how GP is applicable to experimental studies of animal foraging, using the bumble-bee Bombus terrestris. GP techniques enable us to simplify complex patterns of spatial data down to a small number of parameters (2-3) for rigorous hypothesis testing. Combining computer model simulations and experimental observation of foraging bumble-bees, we demonstrate that GP can be used to discriminate between foraging patterns resulting from (i) different hypothetical foraging algorithms and (ii) different food item (flower) densities. We also demonstrate that combining experimental and simulated data can be used to elucidate animal foraging strategies: specifically that the foraging patterns of real bumble-bees can be reliably discriminated from three out of nine hypothetical foraging algorithms. We suggest that experimental systems, like foraging bees, could be used to test and refine GP model predictions, and that GP offers a useful technique to analyse spatial animal behaviour data in both the laboratory and field.
Interactive Voice/Web Response System in clinical research
Ruikar, Vrishabhsagar
2016-01-01
Emerging technologies in computer and telecommunication industry has eased the access to computer through telephone. An Interactive Voice/Web Response System (IxRS) is one of the user friendly systems for end users, with complex and tailored programs at its backend. The backend programs are specially tailored for easy understanding of users. Clinical research industry has experienced revolution in methodologies of data capture with time. Different systems have evolved toward emerging modern technologies and tools in couple of decades from past, for example, Electronic Data Capture, IxRS, electronic patient reported outcomes, etc. PMID:26952178
Interactive Voice/Web Response System in clinical research.
Ruikar, Vrishabhsagar
2016-01-01
Emerging technologies in computer and telecommunication industry has eased the access to computer through telephone. An Interactive Voice/Web Response System (IxRS) is one of the user friendly systems for end users, with complex and tailored programs at its backend. The backend programs are specially tailored for easy understanding of users. Clinical research industry has experienced revolution in methodologies of data capture with time. Different systems have evolved toward emerging modern technologies and tools in couple of decades from past, for example, Electronic Data Capture, IxRS, electronic patient reported outcomes, etc.
Poot, Antonius J.; den Elzen, Wendy P. J.; Blom, Jeanet W.; Gussekloo, Jacobijn
2014-01-01
Background Satisfaction is widely used to evaluate and direct delivery of medical care; a complicated relationship exists between patient satisfaction, morbidity and age. This study investigates the relationships between complexity of health problems and level of patient satisfaction of older persons with their general practitioner (GP) and practice. Methods and Findings This study is embedded in the ISCOPE (Integrated Systematic Care for Older Persons) study. Enlisted patients aged ≥75 years from 59 practices received a written questionnaire to screen for complex health problems (somatic, functional, psychological and social). For 2664 randomly chosen respondents (median age 82 years; 68% female) information was collected on level of satisfaction (satisfied, neutral, dissatisfied) with their GP and general practice, and demographic and clinical characteristics including complexity of health problems. Of all participants, 4% was dissatisfied with their GP care, 59% neutral and 37% satisfied. Between these three categories no differences were observed in age, gender, country of birth or education level. The percentage of participants dissatisfied with their GP care increased from 0.4% in those with 0 problem domains to 8% in those with 4 domains, i.e. having complex health problems (p<0.001). Per additional health domain with problems, the risk of being dissatisfied increased 1.7 times (95% CI 1.4–2.14; p<0.001). This was independent of age, gender, and demographic and clinical parameters (adjusted OR 1.4, 95% CI 1.1–1.8; p = 0.021). Conclusion In older persons, dissatisfaction with general practice is strongly correlated with rising complexity of health problems, independent of age, demographic and clinical parameters. It remains unclear whether complexity of health problems is a patient characteristic influencing the perception of care, or whether the care is unable to handle the demands of these patients. Prospective studies are needed to investigate the causal associations between care organization, patient characteristics, indicators of quality, and patient perceptions. PMID:24710557
Poot, Antonius J; den Elzen, Wendy P J; Blom, Jeanet W; Gussekloo, Jacobijn
2014-01-01
Satisfaction is widely used to evaluate and direct delivery of medical care; a complicated relationship exists between patient satisfaction, morbidity and age. This study investigates the relationships between complexity of health problems and level of patient satisfaction of older persons with their general practitioner (GP) and practice. This study is embedded in the ISCOPE (Integrated Systematic Care for Older Persons) study. Enlisted patients aged ≥75 years from 59 practices received a written questionnaire to screen for complex health problems (somatic, functional, psychological and social). For 2664 randomly chosen respondents (median age 82 years; 68% female) information was collected on level of satisfaction (satisfied, neutral, dissatisfied) with their GP and general practice, and demographic and clinical characteristics including complexity of health problems. Of all participants, 4% was dissatisfied with their GP care, 59% neutral and 37% satisfied. Between these three categories no differences were observed in age, gender, country of birth or education level. The percentage of participants dissatisfied with their GP care increased from 0.4% in those with 0 problem domains to 8% in those with 4 domains, i.e. having complex health problems (p<0.001). Per additional health domain with problems, the risk of being dissatisfied increased 1.7 times (95% CI 1.4-2.14; p<0.001). This was independent of age, gender, and demographic and clinical parameters (adjusted OR 1.4, 95% CI 1.1-1.8; p = 0.021). In older persons, dissatisfaction with general practice is strongly correlated with rising complexity of health problems, independent of age, demographic and clinical parameters. It remains unclear whether complexity of health problems is a patient characteristic influencing the perception of care, or whether the care is unable to handle the demands of these patients. Prospective studies are needed to investigate the causal associations between care organization, patient characteristics, indicators of quality, and patient perceptions.
NASA Astrophysics Data System (ADS)
Stone, Michael
The following sections are included: * Introduction * Free Fermi Fields * Free Bosons * The Bosonization Rules * A Quantum Pythagoras Theorem * Appendix 1A. Complex Coordinates * Appendix IB. Conformal Symmetry * References
Schaper, F; Gendo, C; Eck, M; Schmitz, J; Grimm, C; Anhuf, D; Kerr, I M; Heinrich, P C
1998-11-01
Stimulation of the interleukin-6 (IL-6) signalling pathway occurs via the IL-6 receptor-glycoprotein 130 (IL-6R-gp130) receptor complex and results in the regulation of acute-phase protein genes in liver cells. Ligand binding to the receptor complex leads to tyrosine phosphorylation and activation of Janus kinases (Jak), phosphorylation of the signal transducing subunit gp130, followed by recruitment and phosphorylation of the signal transducer and activator of transcription factors STAT3 and STAT1 and the src homology domain (SH2)-containing protein tyrosine phosphatase (SHP2). The tyrosine phosphorylated STAT factors dissociate from the receptor, dimerize and translocate to the nucleus where they bind to enhancer sequences of IL-6 target genes. Phosphorylated SHP2 is able to bind growth factor receptor bound protein (grb2) and thus might link the Jak/STAT pathway to the ras/raf/mitogen-activated protein kinase pathway. Here we present data on the dose-dependence, kinetics and kinase requirements for SHP2 phosphorylation after the activation of the signal transducer, gp130, of the IL-6-type family receptor complex. When human fibrosarcoma cell lines deficient in Jak1, Jak2 or tyrosine kinase 2 (Tyk2) were stimulated with IL-6-soluble IL-6R complexes it was found that only in Jak1-, but not in Jak 2- or Tyk2-deficient cells, SHP2 activation was greatly impaired. It is concluded that Jak1 is required for the tyrosine phosphorylation of SHP2. This phosphorylation depends on Tyr-759 in the cytoplasmatic domain of gp130, since a Tyr-759-->Phe exchange abrogates SHP2 activation and in turn leads to elevated and prolonged STAT3 and STAT1 activation as well as enhanced acute-phase protein gene induction. Therefore, SHP2 plays an important role in acute-phase gene regulation.
Flanagan, Emma C; Lagarde, Julien; Hahn, Valérie; Guichart-Gomez, Elodie; Sarazin, Marie; Hornberger, Michael; Bertoux, Maxime
2018-05-01
Environmental dependency syndrome (EDS), including utilization (UB) and imitation (IB) behaviors, is often reported in behavioral variant frontotemporal dementia (bvFTD). These behaviors are commonly attributed to executive dysfunction. However, inconsistent associations between EDS and poor executive performance has led to an alternative "social hypothesis," instead implicating patients' misinterpretation of the examiner's intention. We investigated the possible explanatory cognitive mechanisms of EDS in bvFTD by relating UB and IB to performance on tests of executive functioning and theory of mind (ToM). This study analyzed retrospective data of 32 bvFTD patients. Data included scores of UB and IB, various executive measures, and ToM assessment using the faux pas test, from which we extracted a mental attribution score. Of the patients, 15.6% and 40.6% exhibited UB and IB, respectively. We conducted an automatic linear modeling analysis with executive and mental attribution measures as predictor variables, and UB and IB sequentially considered as target variables. ToM mental attribution score, visual abstraction and flexibility measures from the Wisconsin Card Sorting Test, and motor sequence performance significantly (corrected ps < .05) predicted IB. No executive or ToM measures significantly predicted UB. These findings reveal a complex interaction between executive dysfunction and mental attribution deficits influencing the prevalence of EDS in bvFTD. Further investigation is required to improve our understanding of the mechanisms underlying these behaviors. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
2010-01-01
Changes to the glycosylation profile on HIV gp120 can influence viral pathogenesis and alter AIDS disease progression. The characterization of glycosylation differences at the sequence level is inadequate as the placement of carbohydrates is structurally complex. However, no structural framework is available to date for the study of HIV disease progression. In this study, we propose a novel machine-learning based framework for the prediction of AIDS disease progression in three stages (RP, SP, and LTNP) using the HIV structural gp120 profile. This new intelligent framework proves to be accurate and provides an important benchmark for predicting AIDS disease progression computationally. The model is trained using a novel HIV gp120 glycosylation structural profile to detect possible stages of AIDS disease progression for the target sequences of HIV+ individuals. The performance of the proposed model was compared to seven existing different machine-learning models on newly proposed gp120-Benchmark_1 dataset in terms of error-rate (MSE), accuracy (CCI), stability (STD), and complexity (TBM). The novel framework showed better predictive performance with 67.82% CCI, 30.21 MSE, 0.8 STD, and 2.62 TBM on the three stages of AIDS disease progression of 50 HIV+ individuals. This framework is an invaluable bioinformatics tool that will be useful to the clinical assessment of viral pathogenesis. PMID:21143806
Characterization of Clostridium perfringens iota-toxin genes and expression in Escherichia coli.
Perelle, S; Gibert, M; Boquet, P; Popoff, M R
1993-12-01
The iota toxin which is produced by Clostridium perfringens type E, is a binary toxin consisting of two independent polypeptides: Ia, which is an ADP-ribosyltransferase, and Ib, which is involved in the binding and internalization of the toxin into the cell. Two degenerate oligonucleotide probes deduced from partial amino acid sequence of each component of C. spiroforme toxin, which is closely related to the iota toxin, were used to clone three overlapping DNA fragments containing the iota-toxin genes from C. perfringens type E plasmid DNA. Two genes, in the same orientation, coding for Ia (387 amino acids) and Ib (875 amino acids) and separated by 243 noncoding nucleotides were identified. A predicted signal peptide was found for each component, and the secreted Ib displays two domains, the propeptide (172 amino acids) and the mature protein (664 amino acids). The Ia gene has been expressed in Escherichia coli and C. perfringens, under the control of its own promoter. The recombinant polypeptide obtained was recognized by Ia antibodies and ADP-ribosylated actin. The expression of the Ib gene was obtained in E. coli harboring a recombinant plasmid encompassing the putative promoter upstream of the Ia gene and the Ia and Ib genes. Two residues which have been found to be involved in the NAD+ binding site of diphtheria and pseudomonas toxins are conserved in the predicted Ia sequence (Glu-14 and Trp-19). The predicted amino acid Ib sequence shows 33.9% identity with and 54.4% similarity to the protective antigen of the anthrax toxin complex. In particular, the central region of Ib, which contains a predicted transmembrane segment (Leu-292 to Ser-308), presents 45% identity with the corresponding protective antigen sequence which is involved in the translocation of the toxin across the cell membrane.
Coletta, Andrea; Desideri, Alessandro
2013-01-01
Camptothecin (CPT) is a topoisomerase IB (TopIB) selective inhibitor whose derivatives are currently used in cancer therapy. TopIB cleaves DNA at any sequence, but in the presence of CPT the only stabilized protein–DNA covalent complex is the one having a thymine in position −1 with respect to the cleavage site. A metadynamics simulation of two TopIB–DNA–CPT ternary complexes differing for the presence of a thymine or a cytosine in position −1 indicates the occurrence of two different drug’s unbinding pathways. The free-energy difference between the bound state and the transition state is large when a thymine is present in position −1 and is strongly reduced in presence of a cytosine, in line with the different drug stabilization properties of the two systems. Such a difference is strictly related to the changes in the hydrogen bond network between the protein, the DNA and the drug in the two systems, indicating a direct role of the protein in determining the specificity of the cleavage site sequence stabilized by the CPT. Calculations carried out in presence of one compound of the indenoisoquinoline family (NSC314622) indicate a comparable energy difference between the bound and the transition state independently of the presence of a thymine or a cytosine in position −1, in line with the experimental results. PMID:24003027
The Structure of Gene Product 6 of Bacteriophage T4, the Hinge-Pin of the Baseplate
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aksyuk, Anastasia A.; Leiman, Petr G.; Shneider, Mikhail M.
2009-07-21
The baseplate of bacteriophage T4 is a multicomponent protein complex, which controls phage attachment to the host. It assembles from six wedges and a central hub. During infection the baseplate undergoes a large conformational change from a dome-shaped to a flat, star-shaped structure. We report the crystal structure of the C-terminal half of gene product (gp) 6 and investigate its motion with respect to the other proteins during the baseplate rearrangement. Six gp6 dimers interdigitate, forming a ring that maintains the integrity of the baseplate in both conformations. One baseplate wedge contains an N-terminal dimer of gp6, whereas neighboring wedgesmore » are tied together through the C-terminal dimer of gp6. The dimeric interactions are preserved throughout the rearrangement of the baseplate. However, the hinge angle between the N- and C-terminal parts of gp6 changes by {approx}15{sup o}, accounting for a 10 {angstrom} radial increase in the diameter of the gp6 ring.« less
Abal-Fabeiro, J L; Maside, X; Llovo, J; Bello, X; Torres, M; Treviño, M; Moldes, L; Muñoz, A; Carracedo, A; Bartolomé, C
2014-04-01
The epidemiological study of human cryptosporidiosis requires the characterization of species and subtypes involved in human disease in large sample collections. Molecular genotyping is costly and time-consuming, making the implementation of low-cost, highly efficient technologies increasingly necessary. Here, we designed a protocol based on MALDI-TOF mass spectrometry for the high-throughput genotyping of a panel of 55 single nucleotide variants (SNVs) selected as markers for the identification of common gp60 subtypes of four Cryptosporidium species that infect humans. The method was applied to a panel of 608 human and 63 bovine isolates and the results were compared with control samples typed by Sanger sequencing. The method allowed the identification of species in 610 specimens (90·9%) and gp60 subtype in 605 (90·2%). It displayed excellent performance, with sensitivity and specificity values of 87·3 and 98·0%, respectively. Up to nine genotypes from four different Cryptosporidium species (C. hominis, C. parvum, C. meleagridis and C. felis) were detected in humans; the most common ones were C. hominis subtype Ib, and C. parvum IIa (61·3 and 28·3%, respectively). 96·5% of the bovine samples were typed as IIa. The method performs as well as the widely used Sanger sequencing and is more cost-effective and less time consuming.
Tauber, R; Schenck, I; Josić, D; Gross, V; Heinrich, P C; Gerok, W; Reutter, W
1986-09-01
Rat liver synthesizes a glycoprotein with Mr of 80.000 (gp 80) which is partly inserted into the plasma membrane and partly secreted into the serum. The membrane-integrated and the secretory form of this glycoprotein have an identical peptide pattern, but different N-linked glycans. Whereas gp 80 from the serum is glycosylated with complex-type oligosaccharides, gp 80 from the plasma membrane has high mannose glycans. Phase separation with Triton X-114 showed that membrane-integrated gp 80 contains hydrophobic portions, whereas secretory gp 80 has hydrophilic properties. Intracellular transport and oligosaccharide processing of gp 80 were studied in vivo in the endoplasmic reticulum, the Golgi apparatus and plasma membranes of rat liver and in serum using pulse-chase labeling with L-[35S]methionine and immunoprecipitation. Peak labeling of gp 80 was reached in the endoplasmic reticulum 10 min after the pulse, in the Golgi apparatus 20 min later, and in the plasma membrane after 2 h; in the serum the specific radioactivity was steadily increasing during the experiment. Gp 80 of the endoplasmic reticulum was completely sensitive to endo-beta-N-glucosaminidase H (endo H), but simultaneously occurred in the Golgi apparatus in an endo H-sensitive and endo H-resistant form. The endo H-sensitive form was transported to the plasma membrane, the endo H-resistant species secreted into the serum. Conversion from the endo H-sensitive to the endo H-resistant form was completed within 10 min after transfer of gp 80 to the Golgi apparatus.(ABSTRACT TRUNCATED AT 250 WORDS)
You, Jun; Zhou, Jinping; Li, Qian; Zhang, Lina
2012-03-20
As a weak base, β-glycerophosphate (β-GP) was used to spontaneously initiate gelation of quaternized cellulose (QC) solutions at body temperature. The QC/β-GP solutions are flowable below or at room temperature but gel rapidly under physiological conditions. In order to clarify the sol-gel transition process of the QC/β-GP systems, the complex was investigated by dynamic viscoelastic measurements. The shear storage modulus (G') and loss modulus (G″) as a function of (1) concentration of β-GP (c(β-GP)), (2) concentration of QC (c(QC)), (3) degree of substitution (DS; i.e., the average number of substituted hydroxyl groups in the anhydroglucose unit) of QC, (4) viscosity-average molecular weight (M(η)) of QC, and (5) solvent medium were studied by the oscillatory rheology. The sol-gel transition temperature of QC/β-GP solutions decreased with an increase of c(QC) and c(β-GP), the M(η) of QC, and a decrease of the DS of QC and pH of the solvent. The sol-gel transition temperature and time could be easily controlled by adjusting the concentrations of QC and β-GP, M(η) and DS of QC, and the solvent medium. Gels formed after heating were irreversible; i.e., after cooling to lower temperature they could not be dissolved to become liquid again. The aggregation and entanglement of QC chains, electrostatic interaction, and hydrogen bonding between QC and β-GP were the main factors responsible for the irreversible sol-gel transition behavior of QC/β-GP systems.
Model of a ternary complex between activated factor VII, tissue factor and factor IX.
Chen, Shu-wen W; Pellequer, Jean-Luc; Schved, Jean-François; Giansily-Blaizot, Muriel
2002-07-01
Upon binding to tissue factor, FVIIa triggers coagulation by activating vitamin K-dependent zymogens, factor IX (FIX) and factor X (FX). To understand recognition mechanisms in the initiation step of the coagulation cascade, we present a three-dimensional model of the ternary complex between FVIIa:TF:FIX. This model was built using a full-space search algorithm in combination with computational graphics. With the known crystallographic complex FVIIa:TF kept fixed, the FIX docking was performed first with FIX Gla-EGF1 domains, followed by the FIX protease/EGF2 domains. Because the FIXa crystal structure lacks electron density for the Gla domain, we constructed a chimeric FIX molecule that contains the Gla-EGF1 domains of FVIIa and the EGF2-protease domains of FIXa. The FVIIa:TF:FIX complex has been extensively challenged against experimental data including site-directed mutagenesis, inhibitory peptide data, haemophilia B database mutations, inhibitor antibodies and a novel exosite binding inhibitor peptide. This FVIIa:TF:FIX complex provides a powerful tool to study the regulation of FVIIa production and presents new avenues for developing therapeutic inhibitory compounds of FVIIa:TF:substrate complex.
Shiozawa, Maho; Takahashi, Hidekazu; Iwasaki, Naohiko; Uo, Motohiro
2013-01-01
The objective of this study was to evaluate the effect of the concentration of calcium chloride (CaCl2) solution on the surface hardness of restorative glass ionomer cements (GICs). Two high-viscosity GICs, Fuji IX GP and GlasIonomer FX-II, were immersed in several concentrations of CaCl2 solution for 1 day and 1 week. The immersed specimen surfaces were evaluated using microhardness testing, grazing incidence X-ray diffraction, and energy-dispersive X-ray spectroscopy. Immersion in a higher concentration of CaCl2 solution produced a greater increase in the surface hardness. No crystalline substance was observed on the immersed surface. Calcium ions were selectively absorbed in the matrix of the GIC surface after immersion. They reacted with the non-reacted carboxylic acid groups remaining in the cement matrix. These reactions were considered to cause an increase in the surface hardness of the GICs.
Ha, Ninh Thi; Harris, Mark; Preen, David; Robinson, Suzanne; Moorin, Rachael
2018-04-01
We aimed to characterise use of general practitioners (GP) simultaneously across multiple attributes in people with diabetes and examine its impact on diabetes related potentially preventable hospitalisations (PPHs). Five-years of panel data from 40,625 adults with diabetes were sourced from Western Australian administrative health records. Cluster analysis (CA) was used to group individuals with similar patterns of GP utilisation characterised by frequency and recency of services. The relationship between GP utilisation cluster and the risk of PPHs was examined using multivariable random-effects negative binomial regression. CA categorised GP utilisation into three clusters: moderate; high and very high usage, having distinct patient characteristics. After adjusting for potential confounders, the rate of PPHs was significantly lower across all GP usage clusters compared with those with no GP usage; IRR = 0.67 (95%CI: 0.62-0.71) among the moderate, IRR = 0.70 (95%CI 0.66-0.73) high and IRR = 0.76 (95%CI 0.72-0.80) very high GP usage clusters. Combination of temporal factors with measures of frequency of use of GP services revealed patterns of primary health care utilisation associated with different underlying patient characteristics. Incorporation of multiple attributes, that go beyond frequency-based approaches may better characterise the complex relationship between use of GP services and diabetes-related hospitalisation. Copyright © 2018 Elsevier B.V. All rights reserved.
Konduru, Krishnamurthy; Bradfute, Steven B.; Jacques, Jerome; Manangeeswaran, Mohanraj; Nakamura, Siham; Morshed, Sufi; Wood, Steven C.; Bavari, Sina
2011-01-01
Ebola virus is a Filoviridae that causes hemorrhagic fever in humans and induces high morbidity and mortality rates. Filoviruses are classified as "Category A bioterrorism agents", and currently there are no licensed therapeutics or vaccines to treat and prevent infection. The Filovirus glycoprotein (GP) is sufficient to protect individuals against infection, and several vaccines based on GP are under development including recombinant adenovirus, parainfluenza virus, Venezuelan equine encephalitis virus, vesicular stomatitis virus (VSV) and virus-like particles. Here we describe the development of a GP Fc fusion protein as a vaccine candidate. We expressed the extracellular domain of the Zaire Ebola virus (ZEBOV) GP fused to the Fc fragment of human IgG1 (ZEBOVGP-Fc) in mammalian cells and showed that GP undergoes the complex furin cleavage and processing observed in the native membrane-bound GP. Mice immunized with ZEBOVGP-Fc developed T-cell immunity against ZEBOV GP and neutralizing antibodies against replication-competent VSV-G deleted recombinant VSV containing ZEBOV GP. The ZEBOVGP-Fc vaccinated mice were protected against challenge with a lethal dose of ZEBOV. These results show that vaccination with the ZEBOVGP-Fc fusion protein alone without the need of a viral vector or assembly into virus-like particles is sufficient to induce protective immunity against ZEBOV in mice. Our data suggested that Filovirus GP Fc fusion proteins could be developed as a simple, safe, efficacious, and cost effective vaccine against Filovirus infection for human use. PMID:21329775
Uchtenhagen, Hannes; Abualrous, Esam T; Stahl, Evi; Allerbring, Eva B; Sluijter, Marjolein; Zacharias, Martin; Sandalova, Tatyana; van Hall, Thorbald; Springer, Sebastian; Nygren, Per-Åke; Achour, Adnane
2013-11-01
The immunogenicity of H-2D(b) (D(b)) restricted epitopes can be significantly increased by substituting peptide position 3 to a proline (p3P). The p3P modification enhances MHC stability without altering the conformation of the modified epitope allowing for T-cell cross-reactivity with the native peptide. The present study reveals how specific interactions between p3P and the highly conserved MHC heavy chain residue Y159 increase the stability of D(b) in complex with an optimized version of the melanoma-associated epitope gp10025-33 . Furthermore, the p3P modification directly increased the affinity of the D(b)/gp10025-33 -specific T-cell receptor (TCR) pMel. Surprisingly, the enhanced TCR binding was independent from the observed increased stability of the optimized D(b)/gp10025-33 complex and from the interactions formed between p3P and Y159, indicating a direct effect of the p3P modification on TCR recognition. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Artificial light-regulation of an allosteric bi-enzyme complex by a photosensitive ligand.
Kneuttinger, Andrea C; Winter, Martin; Simeth, Nadja A; Heyn, Kristina; Merkl, Rainer; König, Burkhard; Sterner, Reinhard
2018-05-29
The artificial regulation of proteins by light is an emerging sub-discipline of synthetic biology. Here, we used this concept in order to photo-control both catalysis and allostery within the heterodimeric enzyme complex imidazole glycerol phosphate synthase (ImGP-S). The ImGP-S consists of the cyclase subunit HisF and the glutaminase subunit HisH, which is allosterically stimulated by substrate binding to HisF. We show that a light-sensitive diarylethene (DTE)-based competitive inhibitor in its ring-open state binds with low micromolar affinity to the cyclase subunit and displaces its substrate from the active site. As a consequence, catalysis by HisF and allosteric stimulation of HisH are impaired. Following UV-light irradiation, the DTE-ligand adopts its ring-closed state and loses affinity for HisF, restoring activity and allostery. Our approach allows for the switching of ImGP-S activity and allostery during catalysis and appears to be generally applicable for the light-regulation of other multi-enzyme complexes. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Bonfiglio, Ferdinando; Zheng, Tenghao; Garcia-Etxebarria, Koldo; Hadizadeh, Fatemeh; Bujanda, Luis; Bresso, Francesca; Agreus, Lars; Andreasson, Anna; Dlugosz, Aldona; Lindberg, Greger; Schmidt, Peter T; Karling, Pontus; Ohlsson, Bodil; Simren, Magnus; Walter, Susanna; Nardone, Gerardo; Cuomo, Rosario; Usai-Satta, Paolo; Galeazzi, Francesca; Neri, Matteo; Portincasa, Piero; Bellini, Massimo; Barbara, Giovanni; Latiano, Anna; Hübenthal, Matthias; Thijs, Vincent; Netea, Mihai G; Jonkers, Daisy; Chang, Lin; Mayer, Emeran A; Wouters, Mira M; Boeckxstaens, Guy; Camilleri, Michael; Franke, Andre; Zhernakova, Alexandra; D'Amato, Mauro
2018-04-04
Genetic factors are believed to affect risk for irritable bowel syndrome (IBS), but there have been no sufficiently powered and adequately sized studies. To identify DNA variants associated with IBS risk, we performed a genome-wide association study (GWAS) of the large UK Biobank population-based cohort, which includes genotype and health data from 500,000 participants. We studied 7,287,191 high-quality single-nucleotide polymorphisms in individuals who self-reported a doctor's diagnosis of IBS (cases; m=9576) compared to the remainder of the cohort (controls; n=336,499) (mean age of study subjects, 40-69 years). Genome-wide significant findings were further investigated in 2045 patients with IBS from tertiary centers and 7955 population controls from Europe and the United States, and a small general population sample from Sweden (n=249). Functional annotation of GWAS results was carried out by integrating data from multiple biorepositories, to obtain biological insights from the observed associations. We identified a genome-wide significant association on chromosome 9q31.2 (SNP rs10512344; P=3.57×10 -8 ), in a region previously linked to age at menarche, and 13 additional loci of suggestive significance (P<5.0×10 -6 ). Sex-stratified analyses revealed that the variants at 9q32.1 affect risk of IBS in only women (P=4.29×10 -10 in UK Biobank) and also associate with constipation-predominant IBS in women (P=.015 in the tertiary cohort) and harder stools in women (P=.0012 in the population-based sample). Functional annotation of the 9q32.1 locus identified 8 candidate genes, including the elongator complex protein 1 gene (ELP1 or IKBKAP), which is mutated in patients with familial dysautonomia. In a sufficiently powered GWAS of IBS, we associated variants at the locus 9q32.1 with risk of IBS in women. This observation may provide additional rationale for investigating the role of sex hormones and autonomic dysfunction in IBS. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Brown, A.; Ayres, T. R.; Harper, G. M.; Osten, R. A.; Linsky, J. L.; Dupree, A. K.; Jordan, C.
2000-05-01
Yellow supergiants with spectral types F-G show a complex pattern of outer atmospheric structure with stellar wind and activity indicators varying significantly for stars with similar positions in the H-R diagram. The efficiency of the processes driving their stellar winds and heating their atmospheres is critically dependent on the evolutionary position and surface gravity of each star. We present high-resolution ultraviolet HST/STIS and HST/GHRS spectra for a range of intermediate mass F and G supergiants, including Alpha Car (F0 Ib), Beta Cam (G0 Ib), Beta Dra (G2 Ib), and Epsilon Gem (G8 Ib), and compare the atmospheric properties of these stars with lower luminosity giants and bright giants. We provide a systematic overview of the supergiant atmospheric properties dealing particularly with activity levels, the presence of hot ``transition region'' plasma, signatures of wind outflow, and the role of overlying cool absorbing plasma that becomes increasingly prominent for the cooler stars like Epsilon Gem. This work is supported by HST grants for program GO-08280 and by NASA grant NAG5-3226.
Signatures of Pacific-type orogeny in Lleyn and Anglesey areas, northwest Wales
NASA Astrophysics Data System (ADS)
Asanuma, H.; Okada, Y.; Sawaki, Y.; Yamamoto, S.; Hirata, T.; Maruyama, S.
2014-12-01
The orogeny is a fundamental process of plate tectonics, and its record is useful for understanding of ancient plate motion. Geotectonic history of British isles has been explained by collision-type orogeny accompanied by closure of Iapetus ocean. High pressure metamorphic rocks such as blueschist and eclogite characterizing Pacific-type orogeny occur in some places, but have not attracted much interests because of their smallness. The subduction-related (Pacific-type) orogeny is characterized by contemporaneous formation of a batholith belt, a regional metamorphic belt (high P/T type) and an accretionary complex. Late Proterozoic-Cambrian (677-498 Ma) calc-alkaline volcano-plutonic complexes crop out in Lleyn and Anglesey areas, northwest Wales. The metamorphic age of high-P/T metamorphic belt in eastern Anglesey was constrained by Ar-Ar isochron age of 560-550 Ma. However, depositional age of the rocks composing accretionary complex wasn't fully constrained due to the limited zircon U-Pb age data and vague microfossil records. Monian Supergroup at Lleyn and Anglesey areas includes three groups; South Stack Group (Gp), New Harbour Gp and Gwna Gp. The Gwna Gp is located at the structural top and includes typical rocks of an ocean plate stratigraphy (OPS), a fundamental unit composing of an accretionary complex. We described detailed geological map and reconstructed the OPSs at some localities with careful attention to layer-parallel thrust. In order to constrain the sedimentary ages of each OPS, we collected sandstones from individual OPSs. We determined U-Pb ages of detrital zircons from the sandstones with LA-ICP-MS at Kyoto University. We adopted the youngest age of the detrital zircons as a constraint of sedimentary age. The results indicate that sediments in Gwna Gp deposited from 623 ± 17 Ma to 535 ± 14 Ma. These are contemporary with the ages of both batholith belt and regional metamorphic belt. In addition, it became evident that structurally upper level is older than lower level. This structurally downward-younging polarity is one of the characteristics of accretionary complex. Therefore, we concluded that the accretionary complex at northwestern Wales was formed between 623 ± 17 Ma and 535 ± 14 Ma, and the subduction-related Pacific-type orogeny had formed a part of British Isles.
A Zn-porphyrin complex contributes to bright red color in Parma ham.
Wakamatsu, J; Nishimura, T; Hattori, A
2004-05-01
The Italian traditional dry-cured ham (Parma ham) shows a stable bright red color that is achieved without the use of nitrite and/or nitrate. In this study we examined the pigment spectroscopically, fluoroscopically and by using HPLC and ESI-HR-MASS analysis. Porphyrin derivative other than acid hematin were contained in the HCl-containing acetone extract from Parma ham. A strong fluorescence peak at 588 nm and a weak fluorescence peak at 641 nm were observed. By HPLC analysis the acetone extract of Parma ham was observed at the single peak, which eluted at the same time as Zn-protoporphyrin IX and emitted fluorescence. The results of ESI-HR-MS analysis showed both agreement with the molecular weight of Zn-protoporphyrin IX and the characteristic isotope pattern caused by Zn isotopes. These results suggest that the bright red color in Parma ham is caused by Zn-protoporphyrin IX.
VizieR Online Data Catalog: Candidate X-ray OB stars in MYStIX regions (Povich+, 2017)
NASA Astrophysics Data System (ADS)
Povich, M. S.; Busk, H. A.; Feigelson, E. D.; Townsley, L. K.; Kuhn, M. A.
2017-10-01
X-ray point source catalogs for the 18 Massive Young Star-forming Complex Study in Infrared and X-Rays (MYStIX) regions studied here were produced by Kuhn+ (2010, J/ApJ/725/2485 and 2013, J/ApJS/209/27) and Townsley (2014+, J/ApJS/213/1) from archival Chandra Advanced CCD Imaging Camera (ACIS) observations. MYStIX JHKs NIR photometry was obtained from images taken with the United Kingdom Infrared Telescope (UKIRT) Wide-field Camera or from the Two-Micron All-Sky Survey (2MASS). See section 2 for further details. Spitzer MIR photometry at 3.6, 4.5, 5.8, and 8.0um was provided either by the Galactic Legacy Mid-Plane Survey Extraordinaire (GLIMPSE; Benjamin+ 2003PASP..115..953B) or by Kuhn+ (2013, J/ApJS/209/29). (4 data files).
Star Formation in Nearby Clusters (SFiNCs)
NASA Astrophysics Data System (ADS)
Getman, Konstantin
Most stars form in clusters that rapidly disperse, yet we have a poor understanding of the processes of cluster formation and early evolution. Do clusters form `top-down', rapidly in a dense molecular cloud core? Or, since clouds are turbulent, do clusters form `bottomup' by merging subclusters produced in small kinematically-distinct molecular structures? Do clusters principally form in elongated molecular structures such as Infrared Dark Clouds and Herschel filaments? One of the central reasons for slow progress in resolving these questions is the lack of homogeneous and reliable census of stellar members (both disk-bearing and disk-free) for a wide range of star forming environments. To address these issues we are now completing our major effort, called MYStIX (Massive Young Star-Forming Complex Study in Infrared and X-ray). It combines the Chandra archive with UKIRT+2MASS near-infrared and Spitzer mid-infrared surveys to identify young stellar objects in a wide range of evolutionary stages, from protostars to disk-free pre-main sequence stars, in 20 star forming regions at distances from 0.4 to 3.6 kpc. Each MYStIX region was chosen to have a rich OB-dominated cluster. Started in 2009 with NASA/ADAP and NSF funding, MYStIX has emerged with 8 technical/catalog and the first 4 of a series of science papers (http://astro.psu.edu/mystix). Early MYStIX results include: demonstration of diverse morphologies of young clusters from simple ellipsoids to elongated, clumpy substructures; demonstration of spatio-age gradients across star formation regions; the discovery of core-halo age gradients within two rich nearby MYStIX clusters; and the discovery of important astrophysically empirical correlations among different subcluster properties such as age, absorption, core radius, central stellar density, and total intrinsic population. The early MYStIX result provide new observational evidence for subcluster merging and cluster expansion following gas dissipation. We propose here to extend the MYStIX effort to an archive study of 19 nearer and smaller star forming regions where the stellar clusters are dominated by a single late-OB star rather than numerous O stars as in the MYStIX fields. We call this project `Star Formation in Nearby Clusters' or SFiNCs (homophonic with `sphinx'). With a homogeneous analysis of the Chandra, 2MASS, Spitzer and Herschel archives, we expect to identify and characterize over 50 SFiNCs subclusters. The inferred empirical correlations among different cluster properties for nearly 200 SFiNCs+MYStIX subclusters with 30-3000 detected stars on scales of 0.1-20 pc will allow, for the first time, direct comparison with the results of theoretical simulations of cluster formation to seek deeper answers to the fundamental questions posed above. It is possible, for example, that smaller molecular clouds have less turbulence and thus produce small clusters in a single event rather than through subcluster mergers. Models based on meteoritic isotopes suggest that our Solar System formed in a complex of SFiNCs/MYStIX-like clusters (Gounelle & Meynet 2012, A&A, 545, 4). This project addresses NASA SMD Strategic Subgoals 3C (Advance scientific knowledge of the origin and history of the solar system) and 3D.3 (Understand how individual stars form and how those processes ultimately affect the formation of planetary systems). It lies in the `Star formation and pre-main sequence stars' Research Area of the Astrophysics Data Analysis program.
NASA Technical Reports Server (NTRS)
Askins, B. R.; Davis, S. R.; Heitzman, K. S.; Olsen, R. A.
2011-01-01
On October 28, 2009 the Ares I-X flight test rocket launched from Kennedy Space Center and flew its suborbital trajectory as designed. The mission was successfully completed as data from the test, and associated development activities were analyzed, transferred to stakeholders, and well documented. A positive lesson learned from Ares I-X was that the application of lean thinking principles and kaizen practices was very effective in streamlining development activities. Ares I-X, like other historical rocket development projects, was hampered by technical, cost, and schedule challenges and if not addressed boldly could have resulted in cancellation of the test. The mission management team conducted nine major meetings, referred to as lean events, across its elements to assess plans, procedures, processes, requirements, controls, culture, organization, use of resources, and anything that could be changed to optimize schedule or reduce risk. The preeminent aspect of the lean events was the focus on value added activities and the removal or at least reduction in non-value added activities. Trained Lean Six Sigma facilitators assisted the Ares I-X developers in conducting the lean events. They indirectly helped formulate the mission s own unique methodology for assessing schedule. A core team was selected to lead the events and report to the mission manager. Each activity leveraged specialized participants to analyze the subject matter and its related processes and then recommended alternatives and solutions. Stakeholders were the event champions. They empowered and encouraged the team to succeed. The keys to success were thorough preparation, honest dialog, small groups, adherence to the Ares I-X ground rules, and accountability through disciplined reporting and tracking of actions. This lean event formula was game-changing as demonstrated by Ares I-X. It is highly recommended as a management tool to help develop other complex systems efficiently. The key benefits for Ares I-X were obtaining unambiguous schedule margin, defining enabling options for risk reduction, and most importantly a stronger more unified team.
NASA Technical Reports Server (NTRS)
Askins, B. R.; Davis, S. R.; Heitzman, K. S.; Olsen, R. A.
2011-01-01
On October 28, 2009 the Ares I-X flight test rocket launched from Kennedy Space Center and flew its suborbital trajectory as designed. The mission was successfully completed as data from the test, and associated development activities were analyzed, transferred to stakeholders, and well documented. Positive lessons learned from Ares I-X were that the application of lean thinking principles and kaizen practices are effective in streamlining development activities. Ares I-X, like other historical rocket development projects, was hampered by technical, cost, and schedule challenges and if not addressed boldly could have resulted in cancellation of the test. The mission management team conducted nine major meetings, referred to as lean events, across its elements to assess plans, procedures, processes, requirements, controls, culture, organization, use of resources, and anything that could be changed to optimize schedule or reduce risk. The preeminent aspect of the lean events was the focus on value added activities and the removal or at least reduction in non-value activities. Trained Lean Six Sigma facilitators assisted the Ares I-X developers in conducting the lean events. They indirectly helped formulate the mission s own unique methodology for assessing schedule. A core team was selected to lead the events and report to the mission manager. Each activity leveraged specialized participants to analyze the subject matter and its related processes and then recommended alternatives and solutions. Stakeholders were the event champions. They empowered and encouraged the team to succeed. The keys to success were thorough preparation, honest dialog, small groups, adherence to the Ares I-X ground rules, and accountability through disciplined reporting and tracking of actions. This lean event formula was game-changing as demonstrated by the success of Ares I-X. It is highly recommended as a management tool to help develop other complex systems efficiently. The key benefits for Ares I-X were obtaining unambiguous schedule margin, defining enabling options for risk reduction, and most importantly a stronger more unified team.
Structural Basis of Immune Evasion at the Site of CD4 Attachment on HIV-1 gp120
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Lei; Kwon, Young Do; Zhou, Tongqing
2010-01-13
The site on HIV-1 gp120 that binds to the CD4 receptor is vulnerable to antibodies. However, most antibodies that interact with this site cannot neutralize HIV-1. To understand the basis of this resistance, we determined co-crystal structures for two poorly neutralizing, CD4-binding site (CD4BS) antibodies, F105 and b13, in complexes with gp120. Both antibodies exhibited approach angles to gp120 similar to those of CD4 and a rare, broadly neutralizing CD4BS antibody, b12. Slight differences in recognition, however, resulted in substantial differences in F105- and b13-bound conformations relative to b12-bound gp120. Modeling and binding experiments revealed these conformations to be poorlymore » compatible with the viral spike. This incompatibility, the consequence of slight differences in CD4BS recognition, renders HIV-1 resistant to all but the most accurately targeted antibodies.« less
Maternal dazap2 Regulates Germ Granules by Counteracting Dynein in Zebrafish Primordial Germ Cells.
Forbes, Meredyth M; Rothhämel, Sophie; Jenny, Andreas; Marlow, Florence L
2015-07-07
Primordial germ cells (PGCs) are the stem cells of the germline. Generally, germline induction occurs via zygotic factors or the inheritance of maternal determinants called germ plasm (GP). GP is packaged into ribonucleoprotein complexes within oocytes and later promotes the germline fate in embryos. Once PGCs are specified by either mechanism, GP components localize to perinuclear granular-like structures. Although components of zebrafish PGC germ granules have been studied, the maternal factors regulating their assembly and contribution to germ cell development are unknown. Here, we show that the scaffold protein Dazap2 binds to Bucky ball, an essential regulator of oocyte polarity and GP assembly, and colocalizes with the GP in oocytes and in PGCs. Mutational analysis revealed a requirement for maternal Dazap2 (MDazap2) in germ-granule maintenance. Through molecular epistasis analyses, we show that MDazap2 is epistatic to Tdrd7 and maintains germ granules in the embryonic germline by counteracting Dynein activity. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.
Genetic Programming Transforms in Linear Regression Situations
NASA Astrophysics Data System (ADS)
Castillo, Flor; Kordon, Arthur; Villa, Carlos
The chapter summarizes the use of Genetic Programming (GP) inMultiple Linear Regression (MLR) to address multicollinearity and Lack of Fit (LOF). The basis of the proposed method is applying appropriate input transforms (model respecification) that deal with these issues while preserving the information content of the original variables. The transforms are selected from symbolic regression models with optimal trade-off between accuracy of prediction and expressional complexity, generated by multiobjective Pareto-front GP. The chapter includes a comparative study of the GP-generated transforms with Ridge Regression, a variant of ordinary Multiple Linear Regression, which has been a useful and commonly employed approach for reducing multicollinearity. The advantages of GP-generated model respecification are clearly defined and demonstrated. Some recommendations for transforms selection are given as well. The application benefits of the proposed approach are illustrated with a real industrial application in one of the broadest empirical modeling areas in manufacturing - robust inferential sensors. The chapter contributes to increasing the awareness of the potential of GP in statistical model building by MLR.
The roles of ebolavirus glycoproteins in viral pathogenesis.
Ning, Yun-Jia; Deng, Fei; Hu, Zhihong; Wang, Hualin
2017-02-01
Ebolaviruses are highly dangerous pathogens exhibiting extreme virulence in humans and nonhuman primates. The majority of ebolavirus species, most notably Zaire ebolavirus, can cause Ebola virus disease (EVD), formerly known as Ebola hemorrhagic fever, in humans. EVD is associated with case-fatality rates as high as 90%, and there is currently no specific treatment or licensed vaccine available against EVD. Understanding the molecular biology and pathogenesis of ebolaviruses is important for the development of antiviral therapeutics. Ebolavirus encodes several forms of glycoproteins (GPs), which have some interesting characteristics, including the transcriptional editing coding strategy and extensive O-glycosylation modification, clustered in the mucin-like domain of GP1, full-length GP (GP 1,2 ), and shed GP. In addition to the canonical role of the spike protein, GP 1,2 , in viral entry, ebolavirus GPs appear to have multiple additional functions, likely contributing to the complex pathogenesis of the virus. Here, we review the roles of ebolavirus GPs in viral pathogenesis.
Fragmentation of the CRISPR-Cas Type I-B signature protein Cas8b.
Richter, Hagen; Rompf, Judith; Wiegel, Julia; Rau, Kristina; Randau, Lennart
2017-11-01
CRISPR arrays are transcribed into long precursor RNA species, which are further processed into mature CRISPR RNAs (crRNAs). Cas proteins utilize these crRNAs, which contain spacer sequences that can be derived from mobile genetic elements, to mediate immunity during a reoccurring virus infection. Type I CRISPR-Cas systems are defined by the presence of different Cascade interference complexes containing large and small subunits that play major roles during target DNA selection. Here, we produce the protein and crRNA components of the Type I-B CRISPR-Cas complex of Clostridium thermocellum and Methanococcus maripaludis. The C. thermocellum Cascade complexes were reconstituted and analyzed via size-exclusion chromatography. Activity of the heterologous M. maripaludis CRISPR-Cas system was followed using phage lambda plaques assays. The reconstituted Type-I-B Cascade complex contains Cas7, Cas5, Cas6b and the large subunit Cas8b. Cas6b can be omitted from the reconstitution protocol. The large subunit Cas8b was found to be represented by two tightly associated protein fragments and a small C-terminal Cas8b segment was identified in recombinant complexes and C. thermocellum cell lysate. Production of Cas8b generates a small C-terminal fragment, which is suggested to fulfill the role of the missing small subunit. A heterologous, synthetic M. maripaludis Type I-B system is active in E. coli against phage lambda, highlighting a potential for genome editing using endogenous Type-I-B CRISPR-Cas machineries. This article is part of a Special Issue entitled "Biochemistry of Synthetic Biology - Recent Developments" Guest Editor: Dr. Ilka Heinemann and Dr. Patrick O'Donoghue. Copyright © 2017 Elsevier B.V. All rights reserved.
Wyke, Sally; Hunt, Kate
2008-01-01
Background. Frequent consulting is associated with multiple and complex social and health conditions. It is not known how the impact of multiple conditions, the ability to self-manage and patient perception of the GP consultation combines to influence consulting frequency. Objective. To investigate reasons for frequent consultation among people with multiple morbidity but contrasting consulting rates. Methods. Qualitative study with in-depth interviews in the west of Scotland. Participants were 23 men and women aged about 50 years with four or more chronic illnesses; 11 reported consulting seven or more times in the last year [the frequent consulters (FCs)] and 12, three or fewer times [the less frequent consulters (LFCs)]. The main outcome measures were the participants’ accounts of their symptoms, self-management strategies and reasons for consulting a GP. Results. All participants used multiple self-management strategies. FCs described: more disruptive symptoms, which were resistant to self-management strategies; less access to fewer treatments and resources and more medical monitoring, for unstable conditions and drug regimens. The LFCs reported: less severe and more containable symptoms; accessing more efficacious self-management strategies and infrequent GP monitoring for stable conditions and routine drug regimens. All participants conveyed consulting as a ‘last resort’. However, the GP was seen as ‘ally’, for the FCs, and as ‘innocent bystander’, for the LFCs. Conclusions. This qualitative investigation into the combined significance of multiple morbidities and self-management on the GP consultation suggests that current models of self-management might have limited potential to reduce utilization rates among this vulnerable group. Severity of symptoms, stability of condition and complexity of drug regimens combine to influence the availability of effective resources and influence frequency of GP consultations. PMID:18448858
Mavilio, Alberto; Sisto, Dario; Ferreri, Paolo; Cardascia, Nicola; Alessio, Giovanni
2017-01-01
A significant variability of the second harmonic (2ndH) phase of steady-state pattern electroretinogram (SS-PERG) in intrasession retest has been recently described in glaucoma patients (GP), which has not been found in healthy subjects. To evaluate the reliability of phase variability in retest (a procedure called RE-PERG or REPERG) in the presence of cataract, which is known to affect standard PERG, we tested this procedure in GP, normal controls (NC), and cataract patients (CP). The procedure was performed on 50 GP, 35 NC, and 27 CP. All subjects were examined with RE-PERG and SS-PERG and also with spectral domain optical coherence tomography and standard automated perimetry. Standard deviation of phase and amplitude value of 2ndH were correlated by means of one-way analysis of variance and Pearson correlation, with the mean deviation and pattern standard deviation assessed by standard automated perimetry and retinal nerve fiber layer and the ganglion cell complex thickness assessed by spectral domain optical coherence tomography. Receiver operating characteristics were calculated in cohort populations with and without cataract. Standard deviation of phase of 2ndH was significantly higher in GP with respect to NC ( P <0.001) and CP ( P <0.001), and it correlated with retinal nerve fiber layer ( r =-0.5, P <0.001) and ganglion cell complex ( r =-0.6, P <0.001) defects in GP. Receiver operating characteristic evaluation showed higher specificity of RE-PERG (86.4%; area under the curve 0.93) with respect to SS-PERG (54.5%; area under the curve 0.68) in CP. RE-PERG may improve the specificity of SS-PERG in clinical practice in the discrimination of GP.
Surgical anatomy of the styloid muscles and the extracranial glossopharyngeal nerve.
Prades, J M; Gavid, M; Asanau, A; Timoshenko, A P; Richard, C; Martin, C H
2014-03-01
The purpose of the study was to determine the relationships between the extracranial glossopharyngeal (IX) nerve and the muscles of the styloid diaphragm. In humans, the IX nerve is a hidden retrostyloid nerve which plays a critical role notably in swallowing and has to be preserved during infratemporal fossa and parapharyngeal spaces surgical procedures. In ten adult heads from cadavers (20 sides) fixed in formalin, dissection of the extracranial IX nerve was performed under operating microscope with special attention given to the relationships between this nerve and the styloid muscles of the styloid diaphragm. The three styloid muscles delimit three triangular intermuscular intervals which were each thoroughly explored. Different osseous landmarks were investigated for easy nerve location. The styloid process (SP) is the main superior osseous landmark for the three muscles of the styloid diaphragm. The stylohyoid muscle (SHM) is anteromedially located to the posterior belly of the digastric muscle. The styloglossus muscle (SGM) is medial and anterior to the SHM. The stylopharyngeal muscle (SPM) is the most vertical and medial of the three styloid muscles. It courses from the medial surface of the SP in a deep plane hidden between the SHM and the SGM. The extracranial IX nerve turns around the SPM superiorly with a vertical segment posterior to the SPM and inferiorly with a horizontal segment lateral to the SPM. The meeting point of the two segments of the IX nerve is about 10 mm anteriorly located from the transverse process of the atlas. The external carotid artery and some of its branches lie in contact with the lateral side of the IX nerve. Such relationships between the extracranial IX nerve, the styloid muscles and the transverse process of the atlas should be appreciated by clinician who treats patients with stylohyoid complex syndromes and by the surgeon for the parapharyngeal spaces approach.
García Durán, Marga; Costa, Sofia; Sarraseca, Javier; de la Roja, Nuria; García, Julia; García, Isabel; Rodríguez, Maria José
2016-10-01
The causative agent of Porcine Reproductive and Respiratory Syndrome (PRRS) is an enveloped ssRNA (+) virus belonging to the Arteriviridae family. Gp5 and M proteins form disulfide-linked heterodimers that constitute the major components of PRRSV envelope. Gp2, Gp3, Gp4 and E are the minor structural proteins, being the first three incorporated as multimeric complexes in the virus surface. The disease has become one of the most important causes of economic losses in the swine industry. Despite efforts to design an effective vaccine, the available ones allow only partial protection. In the last years, VLPs have become good vaccine alternatives because of safety issues and their potential to activate both branches of the immunological response. The characteristics of recombinant baculoviruses as heterologous expression system have been exploited for the production of VLPs of a wide variety of viruses. In this work, two multiple baculovirus expression vectors (BEVs) with PRRS virus envelope proteins were engineered in order to generate PRRS VLPs: on the one hand, Gp5 and M cDNAs were cloned to generate the pBAC-Gp5M vector; on the other hand, Gp2, Gp3, Gp4 and E cDNAs have been cloned to generate the pBAC-Gp234E vector. The corresponding recombinant baculoviruses BAC-Gp5M and BAC-Gp234E were employed to produce two types of VLPs: basic Gp5M VLPs, by the simultaneous expression of Gp5 and M proteins; and complete VLPs, by the co-expression of the six PRRS proteins after co-infection. The characterization of VLPs by Western blot confirmed the presence of the recombinant proteins using the available specific antibodies (Abs). The analysis by Electron microscopy showed that the two types of VLPs were indistinguishable between them, being similar in shape and size to the native PRRS virus. This system represents a potential alternative for vaccine development and a useful tool to study the implication of specific PRRS proteins in the response against the virus. Copyright © 2016 Elsevier B.V. All rights reserved.
2009-10-28
CAPE CANAVERAL, Fla. - With more than 23 times the power output of the Hoover Dam, the Constellation Program's Ares I-X test rocket zooms off Launch Complex 39B at NASA's Kennedy Space Center in Florida. The rocket produces 2.96 million pounds of thrust at liftoff and reaches a speed of 100 mph in eight seconds. At right is space shuttle Atlantis, poised on Launch Pad 39A for liftoff, targeted for Nov. 16. Liftoff of the 6-minute flight test was at 11:30 a.m. EDT Oct. 28. This was the first launch from Kennedy's pads of a vehicle other than the space shuttle since the Apollo Program's Saturn rockets were retired. The parts used to make the Ares I-X booster flew on 30 different shuttle missions ranging from STS-29 in 1989 to STS-106 in 2000. The data returned from more than 700 sensors throughout the rocket will be used to refine the design of future launch vehicles and bring NASA one step closer to reaching its exploration goals. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo courtesy of Scott Andrews
ERIC Educational Resources Information Center
Marcovitz, Alan B., Ed.
Described is the use of an analog/hybrid computer installation to study those physical phenomena that can be described through the evaluation of an algebraic function of a complex variable. This is an alternative way to study such phenomena on an interactive graphics terminal. The typical problem used, involving complex variables, is that of…
Vincent, Maxence S.; Canestrari, Mickaël J.; Leone, Philippe; Stathopulos, Julien; Ize, Bérengère; Zoued, Abdelrahim; Cambillau, Christian; Kellenberger, Christine; Roussel, Alain
2017-01-01
The transport of proteins at the cell surface of Bacteroidetes depends on a secretory apparatus known as type IX secretion system (T9SS). This machine is responsible for the cell surface exposition of various proteins, such as adhesins, required for gliding motility in Flavobacterium, S-layer components in Tannerella forsythia, and tooth tissue-degrading enzymes in the oral pathogen Porphyromonas gingivalis. Although a number of subunits of the T9SS have been identified, we lack details on the architecture of this secretion apparatus. Here we provide evidence that five of the genes encoding the core complex of the T9SS are co-transcribed and that the gene products are distributed in the cell envelope. Protein-protein interaction studies then revealed that these proteins oligomerize and interact through a dense network of contacts. PMID:28057754
Analysis of the N-glycans of recombinant human Factor IX purified from transgenic pig milk
Gil, Geun-Cheol; Velander, William H; Van Cott, Kevin E
2008-01-01
Glycosylation of recombinant proteins is of particular importance because it can play significant roles in the clinical properties of the glycoprotein. In this work, the N-glycan structures of recombinant human Factor IX (tg-FIX) produced in the transgenic pig mammary gland were determined. The majority of the N-glycans of transgenic pig-derived Factor IX (tg-FIX) are complex, bi-antennary with one or two terminal N-acetylneuraminic acid (Neu5Ac) moieties. We also found that the N-glycan structures of tg-FIX produced in the porcine mammary epithelial cells differed with respect to N-glycans from glycoproteins produced in other porcine tissues. tg-FIX contains no detectable Neu5Gc, the sialic acid commonly found in porcine glycoproteins produced in other tissues. Additionally, we were unable to detect glycans in tg-FIX that have a terminal Galα(1,3)Gal disaccharide sequence, which is strongly antigenic in humans. The N-glycan structures of tg-FIX are also compared to the published N-glycan structures of recombinant human glycoproteins produced in other transgenic animal species. While tg-FIX contains only complex structures, antithrombin III (goat), C1 inhibitor (rabbit), and lactoferrin (cow) have both high mannose and complex structures. Collectively, these data represent a beginning point for the future investigation of species-specific and tissue/cell-specific differences in N-glycan structures among animals used for transgenic animal bioreactors. PMID:18456721
Terkelsen, Thilde; Haakensen, Vilde D; Saldova, Radka; Gromov, Pavel; Hansen, Merete Kjaer; Stöckmann, Henning; Lingjaerde, Ole Christian; Børresen-Dale, Anne-Lise; Papaleo, Elena; Helland, Åslaug; Rudd, Pauline M; Gromova, Irina
2018-06-01
Particular N-glycan structures are known to be associated with breast malignancies by coordinating various regulatory events within the tumor and corresponding microenvironment, thus implying that N-glycan patterns may be used for cancer stratification and as predictive or prognostic biomarkers. However, the association between N-glycans secreted by breast tumor and corresponding clinical relevance remain to be elucidated. We profiled N-glycans by HILIC UPLC across a discovery dataset composed of tumor interstitial fluids (TIF, n = 85), paired normal interstitial fluids (NIF, n = 54) and serum samples (n = 28) followed by independent evaluation, with the ultimate goal of identifying tumor-related N-glycan patterns in blood of patients with breast cancer. The segregation of N-linked oligosaccharides revealed 33 compositions, which exhibited differential abundances between TIF and NIF. TIFs were depleted of bisecting N-glycans, which are known to play essential roles in tumor suppression. An increased level of simple high mannose N-glycans in TIF strongly correlated with the presence of tumor infiltrating lymphocytes within tumor. At the same time, a low level of highly complex N-glycans in TIF inversely correlated with the presence of infiltrating lymphocytes within tumor. Survival analysis showed that patients exhibiting increased TIF abundance of GP24 had better outcomes, whereas low levels of GP10, GP23, GP38, and coreF were associated with poor prognosis. Levels of GP1, GP8, GP9, GP14, GP23, GP28, GP37, GP38, and coreF were significantly correlated between TIF and paired serum samples. Cross-validation analysis using an independent serum dataset supported the observed correlation between TIF and serum, for five of nine N-glycan groups: GP8, GP9, GP14, GP23, and coreF. Collectively, our results imply that profiling of N-glycans from proximal breast tumor fluids is a promising strategy for determining tumor-derived glyco-signature(s) in the blood. N-glycans structures validated in our study may serve as novel biomarkers to improve the diagnostic and prognostic stratification of patients with breast cancer. © 2018 The Authors. Published by FEBS Press and John Wiley & Sons Ltd.
Geometric multigrid for an implicit-time immersed boundary method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guy, Robert D.; Philip, Bobby; Griffith, Boyce E.
2014-10-12
The immersed boundary (IB) method is an approach to fluid-structure interaction that uses Lagrangian variables to describe the deformations and resulting forces of the structure and Eulerian variables to describe the motion and forces of the fluid. Explicit time stepping schemes for the IB method require solvers only for Eulerian equations, for which fast Cartesian grid solution methods are available. Such methods are relatively straightforward to develop and are widely used in practice but often require very small time steps to maintain stability. Implicit-time IB methods permit the stable use of large time steps, but efficient implementations of such methodsmore » require significantly more complex solvers that effectively treat both Lagrangian and Eulerian variables simultaneously. Moreover, several different approaches to solving the coupled Lagrangian-Eulerian equations have been proposed, but a complete understanding of this problem is still emerging. This paper presents a geometric multigrid method for an implicit-time discretization of the IB equations. This multigrid scheme uses a generalization of box relaxation that is shown to handle problems in which the physical stiffness of the structure is very large. Numerical examples are provided to illustrate the effectiveness and efficiency of the algorithms described herein. Finally, these tests show that using multigrid as a preconditioner for a Krylov method yields improvements in both robustness and efficiency as compared to using multigrid as a solver. They also demonstrate that with a time step 100–1000 times larger than that permitted by an explicit IB method, the multigrid-preconditioned implicit IB method is approximately 50–200 times more efficient than the explicit method.« less
Salústio, P J; Feio, G; Figueirinhas, J L; Pinto, J F; Cabral Marques, H M
2009-02-01
The work aims to prove the complexation of two model drugs (ibuprofen, IB and indomethacin, IN) by beta-cyclodextrin (betaCD), and the effect of water in such a process, and makes a comparison of their complexation yields. Two methods were considered: kneading of a binary mixture of the drug, betaCD, and inclusion of either IB or IN in aqueous solutions of betaCD. In the latter method water was removed by air stream, spray-drying and freeze-drying. To prove the formation of complexes in final products, optical microscopy, UV spectroscopy, IR spectroscopy, DSC, X-ray and NMR were considered. Each powder was added to an acidic solution (pH=2) to quantify the concentration of the drug inside betaCD cavity. Other media (pH=5 and 7) were used to prove the existence of drug not complexed in each powder, as the drugs solubility increases with the pH. It was observed that complexation occurred in all powders, and that the fraction of drug inside the betaCD did not depend neither on the method of complexation nor on the processes of drying considered.
Acciani, Marissa; Alston, Jacob T; Zhao, Guohui; Reynolds, Hayley; Ali, Afroze M; Xu, Brian; Brindley, Melinda A
2017-09-15
Lassa virus (LASV) is an enveloped RNA virus endemic to West Africa and responsible for severe cases of hemorrhagic fever. Virus entry is mediated by the glycoprotein complex consisting of a stable-signal peptide, a receptor-binding subunit, GP1, and a viral-host membrane fusion subunit, GP2. Several cellular receptors can interact with the GP1 subunit and mediate viral entry, including alpha-dystroglycan (αDG) and lysosome-associated membrane protein 1 (LAMP1). In order to define the regions within GP1 that interact with the cellular receptors, we implemented insertional mutagenesis, carbohydrate shielding, and alanine scanning mutagenesis. Eighty GP constructs were engineered and evaluated for GP1-GP2 processing, surface expression, and the ability to mediate cell-to-cell fusion after low-pH exposure. To examine virus-to-cell entry, 49 constructs were incorporated onto vesicular stomatitis virus (VSV) pseudoparticles and transduction efficiencies were monitored in HAP1 and HAP1-ΔDAG1 cells that differentially produce the αDG cell surface receptor. Seven constructs retained efficient transduction in HAP1-ΔDAG1 cells yet poorly transduced HAP1 cells, suggesting that they are involved in αDG utilization. Residues H141, N146, F147, and Y150 cluster at the predicted central core of the trimeric interface and are important for GP-αDG interaction. Additionally, H92A-H93A, 150HA, 172HA, and 230HA displayed reduced transduction in both HAP1 and HAP1-ΔDAG1 cells, despite efficient cell-to-cell fusion activity. These mutations may interfere with interactions with the endosomal receptor LAMP1 or interfere at another stage in entry that is common to both cell lines. Insight gained from these data can aid in the development of more-effective entry inhibitors by blocking receptor interactions. IMPORTANCE Countries in which Lassa virus is endemic, such as Nigeria, Sierra Leone, Guinea, and Liberia, usually experience a seasonal outbreak of the virus from December to March. Currently, there is neither a preventative vaccine nor a therapeutic available to effectively treat severe Lassa fever. One way to thwart virus infection is to inhibit interaction with cellular receptors. It is known that the GP1 subunit of the Lassa glycoprotein complex plays a critical role in receptor recognition. Our results highlight a region within the Lassa virus GP1 protein that interacts with the cellular receptor alpha-dystroglycan. This information may be used for future development of new Lassa virus antivirals. Copyright © 2017 American Society for Microbiology.
Brouillette, Rachel B.; Phillips, Elisabeth K.; Ayithan, Natarajan
2017-01-01
ABSTRACT The glycoprotein complex (GPC) of arenaviruses, composed of stable signal peptide, GP1, and GP2, is the only antigen correlated with antibody-mediated neutralization. However, despite strong cross-reactivity of convalescent antisera between related arenavirus species, weak or no cross-neutralization occurs. Two closely related clade B viruses, Machupo virus (MACV) and Junín virus (JUNV), have nearly identical overall GPC architecture and share a host receptor, transferrin receptor 1 (TfR1). Given structural and functional similarities of the GP1 receptor binding site (RBS) of these viruses and the recent demonstration that the RBS is an important target for neutralizing antibodies, it is not clear how these viruses avoid cross-neutralization. To address this, MACV/JUNV chimeric GPCs were assessed for interaction with a group of α-JUNV GPC monoclonal antibodies (MAbs) and mouse antisera against JUNV or MACV GPC. All six MAbs targeted GP1, with those that neutralized JUNV GPC-pseudovirions competing with each other for RBS binding. However, these MAbs were unable to bind to a chimeric GPC composed of JUNV GP1 containing a small disulfide bonded loop (loop 10) unique to MACV GPC, suggesting that this loop may block MAbs interaction with the GP1 RBS. Consistent with this loop causing interference, mouse anti-JUNV GPC antisera that solely neutralized pseudovirions bearing autologous GP1 provided enhanced neutralization of MACV GPC when this loop was removed. Our studies provide evidence that loop 10, which is unique to MACV GP1, is an important impediment to binding of neutralizing antibodies and contributes to the poor cross-neutralization of α-JUNV antisera against MACV. IMPORTANCE Multiple New World arenaviruses can cause severe disease in humans, and some geographic overlap exists among these viruses. A vaccine that protects against a broad range of New World arenaviruses is desirable for purposes of simplicity, cost, and broad protection against multiple National Institute of Allergy and Infectious Disease-assigned category A priority pathogens. In this study, we sought to better understand how closely related arenaviruses elude cross-species neutralization by investigating the structural bases of antibody binding and avoidance. In our studies, we found that neutralizing antibodies against two New World arenaviruses, Machupo virus (MACV) and Junín virus (JUNV), bound to the envelope glycoprotein 1 (GP1) with JUNV monoclonal antibodies targeting the receptor binding site (RBS). We further show that altered structures surrounding the RBS pocket in MACV GP1 impede access of JUNV-elicited antibodies. PMID:28100617
Brouillette, Rachel B; Phillips, Elisabeth K; Ayithan, Natarajan; Maury, Wendy
2017-04-01
The glycoprotein complex (GPC) of arenaviruses, composed of stable signal peptide, GP1, and GP2, is the only antigen correlated with antibody-mediated neutralization. However, despite strong cross-reactivity of convalescent antisera between related arenavirus species, weak or no cross-neutralization occurs. Two closely related clade B viruses, Machupo virus (MACV) and Junín virus (JUNV), have nearly identical overall GPC architecture and share a host receptor, transferrin receptor 1 (TfR1). Given structural and functional similarities of the GP1 receptor binding site (RBS) of these viruses and the recent demonstration that the RBS is an important target for neutralizing antibodies, it is not clear how these viruses avoid cross-neutralization. To address this, MACV/JUNV chimeric GPCs were assessed for interaction with a group of α-JUNV GPC monoclonal antibodies (MAbs) and mouse antisera against JUNV or MACV GPC. All six MAbs targeted GP1, with those that neutralized JUNV GPC-pseudovirions competing with each other for RBS binding. However, these MAbs were unable to bind to a chimeric GPC composed of JUNV GP1 containing a small disulfide bonded loop (loop 10) unique to MACV GPC, suggesting that this loop may block MAbs interaction with the GP1 RBS. Consistent with this loop causing interference, mouse anti-JUNV GPC antisera that solely neutralized pseudovirions bearing autologous GP1 provided enhanced neutralization of MACV GPC when this loop was removed. Our studies provide evidence that loop 10, which is unique to MACV GP1, is an important impediment to binding of neutralizing antibodies and contributes to the poor cross-neutralization of α-JUNV antisera against MACV. IMPORTANCE Multiple New World arenaviruses can cause severe disease in humans, and some geographic overlap exists among these viruses. A vaccine that protects against a broad range of New World arenaviruses is desirable for purposes of simplicity, cost, and broad protection against multiple National Institute of Allergy and Infectious Disease-assigned category A priority pathogens. In this study, we sought to better understand how closely related arenaviruses elude cross-species neutralization by investigating the structural bases of antibody binding and avoidance. In our studies, we found that neutralizing antibodies against two New World arenaviruses, Machupo virus (MACV) and Junín virus (JUNV), bound to the envelope glycoprotein 1 (GP1) with JUNV monoclonal antibodies targeting the receptor binding site (RBS). We further show that altered structures surrounding the RBS pocket in MACV GP1 impede access of JUNV-elicited antibodies. Copyright © 2017 American Society for Microbiology.
Kistanguri, Gaurav; McCrae, Keith R.
2013-01-01
Immune thrombocytopenia (ITP) is a common hematologic disorder characterized by isolated thrombocytopenia. ITP presents as a primary form characterized by isolated thrombocytopenia (platelet count < 100 × 109/L) in the absence of other causes or disorders that may be associated with thrombocytopenia, or a secondary form in which immune thrombocytopenia develops in association with another disorder that is usually immune or infectious. ITP may affect individuals of all ages, with peaks during childhood and in the elderly, in whom the age specific incidence of ITP is greatest. Bleeding is the most common clinical manifestation of ITP, with the risk of bleeding and related morbidity increased in elderly patients. The pathogenesis of ITP is complex, involving alterations in humoral and cellular immunity. Thrombocytopenia is caused by antibodies that react with glycoproteins expressed on platelets and megakaryocytes (glycoprotein IIb/IIIa, Ib/IX and others), causing shortened survival of circulating platelets and impairing platelet production. Diminished numbers and function of regulatory T cells, as well as the effects of cytotoxic T cells also contribute to the pathogenesis of ITP. Corticosteroids remain the most common first line therapy for ITP, occasionally in conjunction with intravenous immunoglobulin (IVIg) and anti-Rh(D). However, these agents do not lead to durable remissions in the majority of adults with ITP, and considerable heterogeneity exists in the use of second line approaches, which may include splenectomy, Rituximab, or thrombopoietin receptor agonists (TRAs). This review summarizes the classification and diagnosis of primary and secondary ITP, as well as the pathogenesis and options for treatment. Remarkable advances in the understanding and management of ITP have been achieved over the last decade, though many questions remain. PMID:23714309
Genomic Selection in Plant Breeding: Methods, Models, and Perspectives.
Crossa, José; Pérez-Rodríguez, Paulino; Cuevas, Jaime; Montesinos-López, Osval; Jarquín, Diego; de Los Campos, Gustavo; Burgueño, Juan; González-Camacho, Juan M; Pérez-Elizalde, Sergio; Beyene, Yoseph; Dreisigacker, Susanne; Singh, Ravi; Zhang, Xuecai; Gowda, Manje; Roorkiwal, Manish; Rutkoski, Jessica; Varshney, Rajeev K
2017-11-01
Genomic selection (GS) facilitates the rapid selection of superior genotypes and accelerates the breeding cycle. In this review, we discuss the history, principles, and basis of GS and genomic-enabled prediction (GP) as well as the genetics and statistical complexities of GP models, including genomic genotype×environment (G×E) interactions. We also examine the accuracy of GP models and methods for two cereal crops and two legume crops based on random cross-validation. GS applied to maize breeding has shown tangible genetic gains. Based on GP results, we speculate how GS in germplasm enhancement (i.e., prebreeding) programs could accelerate the flow of genes from gene bank accessions to elite lines. Recent advances in hyperspectral image technology could be combined with GS and pedigree-assisted breeding. Copyright © 2017 Elsevier Ltd. All rights reserved.
Expression of an immunogenic Ebola immune complex in Nicotiana benthamiana
Bhoo, Seong Hee; Lai, Huafang; Ma, Julian; Arntzen, Charles J.; Chen, Qiang; Mason, Hugh S.
2014-01-01
Summary Filoviruses (Ebola and Marburg viruses) cause severe and often fatal hemorrhagic fever in humans and non-human primates. The US Centers for Disease Control identify Ebola and Marburg viruses as “category A” pathogens (defined as posing a risk to national security as bioterrorism agents), which has lead to a search for vaccines that could prevent the disease. Because the use of such vaccines would be in the service of public health, the cost of production is an important component of their development. The use of plant biotechnology is one possible way to cost-effectively produce subunit vaccines. In this work, a geminiviral replicon system was used to produce an Ebola immune complex (EIC) in Nicotiana benthamiana. Ebola glycoprotein (GP1) was fused at the C-terminus of the heavy chain of humanized 6D8 IgG monoclonal antibody, which specifically binds to a linear epitope on GP1. Co-expression of the GP1-heavy chain fusion and the 6D8 light chain using a geminiviral vector in leaves of Nicotiana benthamiana produced assembled immunoglobulin, which was purified by ammonium sulfate precipitation and protein G affinity chromatography. Immune complex formation was confirmed by assays to show that the recombinant protein bound the complement factor C1q. Size measurements of purified recombinant protein by dynamic light scattering and size exclusion chromatography also indicated complex formation. Subcutaneous immunization of BALB/C mice with purified EIC resulted in anti-Ebola virus antibody production at levels comparable to those obtained with a GP1 virus-like particle. These results show excellent potential for a plant-expressed EIC as a human vaccine. PMID:21281425
Expression of an immunogenic Ebola immune complex in Nicotiana benthamiana.
Phoolcharoen, Waranyoo; Bhoo, Seong H; Lai, Huafang; Ma, Julian; Arntzen, Charles J; Chen, Qiang; Mason, Hugh S
2011-09-01
Filoviruses (Ebola and Marburg viruses) cause severe and often fatal haemorrhagic fever in humans and non-human primates. The US Centers for Disease Control identifies Ebola and Marburg viruses as 'category A' pathogens (defined as posing a risk to national security as bioterrorism agents), which has lead to a search for vaccines that could prevent the disease. Because the use of such vaccines would be in the service of public health, the cost of production is an important component of their development. The use of plant biotechnology is one possible way to cost-effectively produce subunit vaccines. In this work, a geminiviral replicon system was used to produce an Ebola immune complex (EIC) in Nicotiana benthamiana. Ebola glycoprotein (GP1) was fused at the C-terminus of the heavy chain of humanized 6D8 IgG monoclonal antibody, which specifically binds to a linear epitope on GP1. Co-expression of the GP1-heavy chain fusion and the 6D8 light chain using a geminiviral vector in leaves of N. benthamiana produced assembled immunoglobulin, which was purified by ammonium sulphate precipitation and protein G affinity chromatography. Immune complex formation was confirmed by assays to show that the recombinant protein bound the complement factor C1q. Size measurements of purified recombinant protein by dynamic light scattering and size-exclusion chromatography also indicated complex formation. Subcutaneous immunization of BALB/C mice with purified EIC resulted in anti-Ebola virus antibody production at levels comparable to those obtained with a GP1 virus-like particle. These results show excellent potential for a plant-expressed EIC as a human vaccine. © 2011 The Authors. Plant Biotechnology Journal © 2011 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.
Landis, E.D.; Purcell, M.K.; Thorgaard, G.H.; Wheeler, P.A.; Hansen, J.D.
2008-01-01
Major histocompatibility complex (MHC) molecules are important mediators of cell-mediated immunity in vertebrates. MHC class IA molecules are important for host anti-viral immunity as they present intracellular antigens and regulate natural killer cell (NK) activity. MHC class Ib molecules on the other hand are less understood and have demonstrated diverse immune and non-immune functions in mammals. Rainbow trout possess a single classical MHC IA locus (Onmy-UBA) that is believed to function similar to that of mammalian MHC class Ia. Numerous MHC class Ib genes with undetermined functions have also been described in trout. Here we utilize quantitative reverse transcriptase PCR (qRT-PCR) techniques to survey the levels of basal and inducible transcription for selected trout MHC class Ib genes, sIgM and sentinels of IFN induction in response to viral infection. Basal transcription of all the class Ib genes examined in this study was lower than Onmy-UBA in nai??ve fish. UBA, along with all of the non-classical genes were induced in fish infected with virus but not in control fish. Our results support a non-classical designation for the majority of the class IB genes surveyed in this study based upon expression levels while also indicating that they may play an important role in anti-viral immunity in trout.
Lindfors, Perjohan; Törnblom, Hans; Sadik, Riadh; Björnsson, Einar S; Abrahamsson, Hasse; Simrén, Magnus
2012-12-01
Gut-directed hypnotherapy is an effective treatment in irritable bowel syndrome (IBS) but little is known about the mechanisms of action. In this study we aimed to investigate the effects on gastrointestinal motility when treating IBS with gut-directed hypnotherapy. We randomized 90 patients with IBS, refractory to standard management to receive gut-directed hypnotherapy 1 h/week for 12 weeks or supportive treatment for the same time period. Eighty-one subjects (40 hypnotherapy, 41 controls) could be evaluated by one or more of the following investigations, both before and after the intervention: gastric emptying time, small bowel transit time, colonic transit time, and antroduodenojejunal manometry. No significant differences in gastric emptying time, small bowel transit time, or colonic transit time was found when comparing the baseline and post-intervention measurements in the hypnotherapy group or in the control group. The same was true concerning the results of the antroduodenojejunal manometry. However, there was a numerical trend toward a higher number of migrating motor complexes at manometry and an accelerated gastric emptying time after hypnotherapy that did not reach statistical significance. In this study, we were not able to find evidence for long-standing effects on gastrointestinal motility as a mediator of the effects on IBS when treating the condition with gut-directed hypnotherapy. Further research to understand the mechanism of action is needed.
Landis, Eric D.; Purcell, Maureen K.; Thorgaard, Gary H.; Wheeler , Paul A.; Hansen, John D.
2008-01-01
Major histocompatibility complex (MHC) molecules are important mediators of cell-mediated immunity in vertebrates. MHC class IA molecules are important for host anti-viral immunity as they present intracellular antigens and regulate natural killer cell (NK) activity. MHC class Ib molecules on the other hand are less understood and have demonstrated diverse immune and non-immune functions in mammals. Rainbow trout possess a single classical MHC IA locus (Onmy-UBA) that is believed to function similar to that of mammalian MHC class Ia. Numerous MHC class Ib genes with undetermined functions have also been described in trout. Here we utilize quantitative reverse transcriptase PCR (qRT-PCR) techniques to survey the levels of basal and inducible transcription for selected trout MHC class Ib genes, sIgM and sentinels of IFN induction in response to viral infection. Basal transcription of all the class Ib genes examined in this study was lower than Onmy-UBA in naïve fish. UBA, along with all of the non-classical genes were induced in fish infected with virus but not in control fish. Our results support a non-classical designation for the majority of the class IB genes surveyed in this study based upon expression levels while also indicating that they may play an important role in anti-viral immunity in trout.
Human alpha-defensin-1 protects cells from intoxication with Clostridium perfringens iota toxin.
Fischer, Stephan; Popoff, Michel R; Barth, Holger
2018-03-01
Iota toxin is produced by Clostridium perfringens type E strains and associated with diarrhea in cattle and lambs. This binary protein toxin comprises the enzyme component iota a (Ia), which ADP-ribosylates G-actin, and the separate transport component iota b (Ib), which delivers Ia into the cytosol of target cells. Ib binds to cell receptors and forms biologically active toxin complexes with Ia, which cause rounding of adherent cells due to the destruction of the actin cytoskeleton. Here, we report that the human peptide α-defensin-1 protects cultured cells including human colon cells from intoxication with iota toxin. In contrast, the related ß-defensin-1 had no effect, indicating a specific mode of action. The α-defensin-1 did not inhibit ADP-ribosylation of actin by Ia in vitro. Pretreatment of Ib with α-defensin-1 prior to addition of Ia prevented intoxication. Additionally, α-defensin-1 protected cells from cytotoxic effects mediated by Ib in the absence of Ia, implicating that α-defensin-1 interacts with Ib to prevent the formation of biologically active iota toxin on cells. In conclusion, the findings contribute to a better understanding of the functions of α-defensin-1 and suggest that this human peptide might be an attractive starting point to develop novel pharmacological options to treat/prevent diseases associated with iota toxin-producing Clostridium perfringens strains.
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NASA Astrophysics Data System (ADS)
Liu, Jia-Wei; Yang, Ting; Ma, Lin-Yu; Chen, Xu-Wei; Wang, Jian-Hua
2013-12-01
Nickel nanoparticle decorated graphene (GP-Ni) is prepared by one-pot hydrothermal reduction of graphene oxide and nickel cations by hydrazine hydrate in the presence of poly(sodium-p-styrenesulfonate) (PSS). The GP-Ni hybrid is characterized by XRD, TEM, SEM, XPS, Raman and FT-IR spectra, demonstrating the formation of poly-dispersed nickel nanoparticles with an average size of 83 nm attached on the surface of graphene sheets. The GP-Ni hybrid exhibits ferromagnetic behavior with a magnetization saturation of 31.1 emu g-1 at 10 000 Oersted (Oe). The GP-Ni also possesses favorable stability in aqueous medium and rapid magnetic response to an external magnetic field. These make it a novel magnetic adsorbent for the separation/isolation of His6-tagged recombinant proteins from a complex sample matrix (cell lysate). The targeted protein species is captured onto the surface of the GP-Ni hybrid via specific metal affinity force between polyhistidine groups and nickel nanoparticles. The SDS-PAGE assay indicates highly selective separation of His6-tagged Smt A from cell lysate. The GP-Ni hybrid displays favorable performance on the separation/isolation of His6-tagged recombinant proteins with respect to the commercial NTA-Ni2+ column.
Computation-Guided Backbone Grafting of a Discontinuous Motif onto a Protein Scaffold
DOE Office of Scientific and Technical Information (OSTI.GOV)
Azoitei, Mihai L.; Correia, Bruno E.; Ban, Yih-En Andrew
2012-02-07
The manipulation of protein backbone structure to control interaction and function is a challenge for protein engineering. We integrated computational design with experimental selection for grafting the backbone and side chains of a two-segment HIV gp120 epitope, targeted by the cross-neutralizing antibody b12, onto an unrelated scaffold protein. The final scaffolds bound b12 with high specificity and with affinity similar to that of gp120, and crystallographic analysis of a scaffold bound to b12 revealed high structural mimicry of the gp120-b12 complex structure. The method can be generalized to design other functional proteins through backbone grafting.
Marine Natural Products with P-Glycoprotein Inhibitor Properties
Lopez, Dioxelis; Martinez-Luis, Sergio
2014-01-01
P-glycoprotein (P-gp) is a protein belonging to the ATP-binding cassette (ABC) transporters superfamily that has clinical relevance due to its role in drug metabolism and multi-drug resistance (MDR) in several human pathogens and diseases. P-gp is a major cause of drug resistance in cancer, parasitic diseases, epilepsy and other disorders. This review article aims to summarize the research findings on the marine natural products with P-glycoprotein inhibitor properties. Natural compounds that modulate P-gp offer great possibilities for semi-synthetic modification to create new drugs and are valuable research tools to understand the function of complex ABC transporters. PMID:24451193
Ares I-X Flight Evaluation Tasks in Support of Ares I Development
NASA Technical Reports Server (NTRS)
Huebner, Lawrence D.; Richards, James S.; Coates, Ralph H., III; Cruit, Wendy D.; Ramsey, Matthew N.
2010-01-01
NASA s Constellation Program successfully launched the Ares I-X Flight Test Vehicle on October 28, 2009. The Ares I-X flight was a development flight test that offered a unique opportunity for early engineering data to impact the design and development of the Ares I crew launch vehicle. As the primary customer for flight data from the Ares I-X mission, the Ares Projects Office established a set of 33 flight evaluation tasks to correlate fight results with prospective design assumptions and models. Included within these tasks were direct comparisons of flight data with pre-flight predictions and post-flight assessments utilizing models and modeling techniques being applied to design and develop Ares I. A discussion of the similarities and differences in those comparisons and the need for discipline-level model updates based upon those comparisons form the substance of this paper. The benefits of development flight testing were made evident by implementing these tasks that used Ares I-X data to partially validate tools and methodologies in technical disciplines that will ultimately influence the design and development of Ares I and future launch vehicles. The areas in which partial validation from the flight test was most significant included flight control system algorithms to predict liftoff clearance, ascent, and stage separation; structural models from rollout to separation; thermal models that have been updated based on these data; pyroshock attenuation; and the ability to predict complex flow fields during time-varying conditions including plume interactions.
O'Malley, Dervla
2016-11-01
Irritable bowel syndrome (IBS) is a common disorder characterized by recurrent abdominal pain, bloating, and disturbed bowel habit, symptoms that impact the quality of life of sufferers. The pathophysiological changes underlying this multifactorial condition are complex and include increased sensitivity to luminal and mucosal factors, resulting in altered colonic transit and visceral pain. Moreover, dysfunctional communication in the bidirectional signaling axis between the brain and the gut, which involves efferent and afferent branches of the peripheral nervous system, circulating endocrine hormones, and local paracrine and neurocrine factors, including immune and perhaps even microbial signaling molecules, has a role to play in this disorder. This minireview will examine recent advances in our understanding of the pathophysiology of IBS and assess how cross talk between hormones, immune, and microbe-derived factors and their neuromodulatory effects on peripheral nerves may underlie IBS symptomatology. Copyright © 2016 the American Physiological Society.
Radebaugh, C A; Matthews, J L; Geiss, G K; Liu, F; Wong, J M; Bateman, E; Camier, S; Sentenac, A; Paule, M R
1994-01-01
The role of the Acanthamoeba castellanii TATA-binding protein (TBP) in transcription was examined. Specific antibodies against the nonconserved N-terminal domain of TBP were used to verify the presence of TBP in the fundamental transcription initiation factor for RNA polymerase I, TIF-IB, and to demonstrate that TBP is part of the committed initiation complex on the rRNA promoter. The same antibodies inhibit transcription in all three polymerase systems, but they do so differentially. Oligonucleotide competitors were used to evaluate the accessibility of the TATA-binding site in TIF-IB, TFIID, and TFIIIB. The results suggest that insertion of TBP into the polymerase II and III factors is more similar than insertion into the polymerase I factor.
... IBS Patients' Experience and Unmet Needs IBS and Holidays Personal Stories IBS Awareness Month IBS Awareness Month ... IBS Patients' Experience and Unmet Needs IBS and Holidays Personal Stories IBS Awareness Month IBS Awareness Month ...
... IBS Patients' Experience and Unmet Needs IBS and Holidays Personal Stories IBS Awareness Month IBS Awareness Month ... IBS Patients' Experience and Unmet Needs IBS and Holidays Personal Stories IBS Awareness Month IBS Awareness Month ...
Relaxation Techniques to Manage IBS Symptoms
... IBS Patients' Experience and Unmet Needs IBS and Holidays Personal Stories IBS Awareness Month IBS Awareness Month ... IBS Patients' Experience and Unmet Needs IBS and Holidays Personal Stories IBS Awareness Month IBS Awareness Month ...
1994-01-01
Unlike the highly polymorphic major histocompatibility complex (MHC) class Ia molecules, which present a wide variety of peptides to T cells, it is generally assumed that the nonpolymorphic MHC class Ib molecules may have evolved to function as highly specialized receptors for the presentation of structurally unique peptides. However, a thorough biochemical analysis of one class Ib molecule, the soluble isoform of Qa-2 antigen (H-2SQ7b), has revealed that it binds a diverse array of structurally similar peptides derived from intracellular proteins in much the same manner as the classical antigen-presenting molecules. Specifically, we find that SQ7b molecules are heterodimers of heavy and light chains complexed with nonameric peptides in a 1:1:1 ratio. These peptides contain a conserved hydrophobic residue at the COOH terminus and a combination of one or more conserved residue(s) at P7 (histidine), P2 (glutamine/leucine), and/or P3 (leucine/asparagine) as anchors for binding SQ7b. 2 of 18 sequenced peptides matched cytosolic proteins (cofilin and L19 ribosomal protein), suggesting an intracellular source of the SQ7b ligands. Minimal estimates of the peptide repertoire revealed that at least 200 different naturally processed self-peptides can bind SQ7b molecules. Since Qa-2 molecules associate with a diverse array of peptides, we suggest that they function as effective presenting molecules of endogenously synthesized proteins like the class Ia molecules. PMID:8294869
Characterization of Clostridium perfringens iota-toxin genes and expression in Escherichia coli.
Perelle, S; Gibert, M; Boquet, P; Popoff, M R
1993-01-01
The iota toxin which is produced by Clostridium perfringens type E, is a binary toxin consisting of two independent polypeptides: Ia, which is an ADP-ribosyltransferase, and Ib, which is involved in the binding and internalization of the toxin into the cell. Two degenerate oligonucleotide probes deduced from partial amino acid sequence of each component of C. spiroforme toxin, which is closely related to the iota toxin, were used to clone three overlapping DNA fragments containing the iota-toxin genes from C. perfringens type E plasmid DNA. Two genes, in the same orientation, coding for Ia (387 amino acids) and Ib (875 amino acids) and separated by 243 noncoding nucleotides were identified. A predicted signal peptide was found for each component, and the secreted Ib displays two domains, the propeptide (172 amino acids) and the mature protein (664 amino acids). The Ia gene has been expressed in Escherichia coli and C. perfringens, under the control of its own promoter. The recombinant polypeptide obtained was recognized by Ia antibodies and ADP-ribosylated actin. The expression of the Ib gene was obtained in E. coli harboring a recombinant plasmid encompassing the putative promoter upstream of the Ia gene and the Ia and Ib genes. Two residues which have been found to be involved in the NAD+ binding site of diphtheria and pseudomonas toxins are conserved in the predicted Ia sequence (Glu-14 and Trp-19). The predicted amino acid Ib sequence shows 33.9% identity with and 54.4% similarity to the protective antigen of the anthrax toxin complex. In particular, the central region of Ib, which contains a predicted transmembrane segment (Leu-292 to Ser-308), presents 45% identity with the corresponding protective antigen sequence which is involved in the translocation of the toxin across the cell membrane. Images PMID:8225592
Ali, Ather; Weiss, Theresa R; McKee, Douglas; Scherban, Alisa; Khan, Sumiya; Fields, Maxine R; Apollo, Damian; Mehal, Wajahat Z
2017-01-01
Patients with irritable bowel syndrome (IBS) are often placed on diets guided by food intolerance assays, although these have not been validated. We assessed the effects of individualised diets in patients with IBS guided by a leucocyte activation test. This is a parallel-group, double-blind, randomised controlled trial of 58 adults with IBS seen at an academic health centre in Northeast USA. Peripheral venous blood was analysed using a leucocyte activation test; individual foods were reported to produce positive or negative results. Participants were randomised to a 4-week diet with either individualised guidance to eliminate foods with positive assay results and allow foods with negative assay results (intervention), or with individualised guidance, matched in rigour and complexity, to eliminate foods with negative assay results and allow foods with positive assay results (comparison). The primary outcome was between-group differences in the IBS Global Improvement Scale (GIS). Secondary outcomes included reductions in IBS Symptom Severity Scale (SSS) scores and increases in IBS Adequate Relief (AR) and Quality of Life (QOL) scores. An aptamer-based proteomic analysis was conducted in strong responders. The intervention group had significantly greater increases in mean GIS score after 4 weeks (0.86 vs comparison; 95% CI 0.05 to 1.67; p=0.04) and 8 weeks (1.22 vs comparison; 95% CI 0.22 to 2.22; p=0.02). The intervention group also had significantly greater reductions in mean SSS score at 4 weeks (-61.78 vs comparison; 95% CI -4.43 to -119.14; p=0.04) and 8 weeks (-66.42 vs comparison; 95% CI -5.75 to -127.09; p=0.03). There were no significant differences between intervention and comparison groups in mean AR or QOL scores. A reduction in neutrophil elastase concentration was associated with reduced symptoms. Elimination diets guided by leucocyte activation tests reduced symptoms. These findings could lead to insights into the pathophysiology of IBS. NCT02186743.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Robertson, Amy N.; Wendt, Fabian; Jonkman, Jason M.
This paper summarizes the findings from Phase Ib of the Offshore Code Comparison, Collaboration, Continued with Correlation (OC5) project. OC5 is a project run under the International Energy Agency (IEA) Wind Research Task 30, and is focused on validating the tools used for modelling offshore wind systems through the comparison of simulated responses of select offshore wind systems (and components) to physical test data. For Phase Ib of the project, simulated hydrodynamic loads on a flexible cylinder fixed to a sloped bed were validated against test measurements made in the shallow water basin at the Danish Hydraulic Institute (DHI) withmore » support from the Technical University of Denmark (DTU). The first phase of OC5 examined two simple cylinder structures (Phase Ia and Ib) to focus on validation of hydrodynamic models used in the various tools before moving on to more complex offshore wind systems and the associated coupled physics. As a result, verification and validation activities such as these lead to improvement of offshore wind modelling tools, which will enable the development of more innovative and cost-effective offshore wind designs.« less
Robertson, Amy N.; Wendt, Fabian; Jonkman, Jason M.; ...
2016-10-13
This paper summarizes the findings from Phase Ib of the Offshore Code Comparison, Collaboration, Continued with Correlation (OC5) project. OC5 is a project run under the International Energy Agency (IEA) Wind Research Task 30, and is focused on validating the tools used for modelling offshore wind systems through the comparison of simulated responses of select offshore wind systems (and components) to physical test data. For Phase Ib of the project, simulated hydrodynamic loads on a flexible cylinder fixed to a sloped bed were validated against test measurements made in the shallow water basin at the Danish Hydraulic Institute (DHI) withmore » support from the Technical University of Denmark (DTU). The first phase of OC5 examined two simple cylinder structures (Phase Ia and Ib) to focus on validation of hydrodynamic models used in the various tools before moving on to more complex offshore wind systems and the associated coupled physics. As a result, verification and validation activities such as these lead to improvement of offshore wind modelling tools, which will enable the development of more innovative and cost-effective offshore wind designs.« less
Watier, Alain; Rigaud, Jérôme; Labat, Jean-Jacques
2010-11-01
To define functional gastrointestinal pain, irritable bowel syndrome (IBS), levator ani syndrome, proctalgia fugax, the pathophysiology of these syndromes and the treatments that can be proposed. Review of articles published on the theme based on a Medline (PubMed) search and consensus conferences selected according to their scientific relevance. IBS is very common. Patients report abdominal pain and/or discomfort, bloating, and abnormal bowel habit (diarrhoea, constipation or both), in the absence of any structural or biochemical abnormalities. IBS has a complex, multifactorial pathophysiology, involving biological and psychosocial interactions resulting in dysregulation of the brain-gut axis associated with disorders of intestinal motility, hyperalgesia, immune disorders and disorders of the intestinal bacterial microflora and autonomic and hormonal dysfunction. Many treatments have been proposed, ranging from diet to pharmacology and psychotherapy. Patients with various types of chronic pelvic and perineal pain, especially those seen in urology departments, very often report associated IBS. This syndrome is also part of a global and integrated concept of pelviperineal dysfunction, avoiding a rigorous distinction between the posterior segment and the midline and anterior segments of the perineum. Copyright © 2010 Elsevier Masson SAS. All rights reserved.
Park, Bo-Kyung; Chun, Eunho; Choi, Jeong June; Shin, Younmin; Kho, Young Tak; Oh, Seung Hyun; Kim, Sun Yeou; Lee, Taek Hwan; Kim, Tae-Wan; Shin, Eunju; Do, Seon-Gil; Jin, Mirim
2017-05-01
Irritable bowel syndrome (IBS) is a functional gastrointestinal disease with complex pathophysiology involving the brain-gut axis. To assess the effects of Wasabia koreana (WK) on IBS, we employed a mouse model of colonic zymosan injection presenting with diarrhea-predominant IBS-like symptoms. Oral WK administration significantly diminished stool score, suppressed colon length and weight change, and minimized body weight loss without affecting food intake. In WK-treated mice, the submucosal thickening and epithelial lining of the colon were inhibited and were similar to those of naïve mice. Infiltration of mast cells into the colon and serum tumor necrosis factor-α levels were markedly suppressed. These effects were comparable to those of sulfasalazine, an anti-inflammatory drug. Furthermore, the number of visceral pain-related behaviors was significantly decreased, and locomotion activities measured in the elevated plus maze and open field tests were significantly increased by WK in a dose-dependent manner compared with amitriptyline, an antidepressant. These changes were accompanied by reduced FosB2 expression in the brain. Taken together, these data suggest that WK may have potential as a medicinal food for IBS by acting on inflammatory diarrhea and neural activity.
Semantic Web meets Integrative Biology: a survey.
Chen, Huajun; Yu, Tong; Chen, Jake Y
2013-01-01
Integrative Biology (IB) uses experimental or computational quantitative technologies to characterize biological systems at the molecular, cellular, tissue and population levels. IB typically involves the integration of the data, knowledge and capabilities across disciplinary boundaries in order to solve complex problems. We identify a series of bioinformatics problems posed by interdisciplinary integration: (i) data integration that interconnects structured data across related biomedical domains; (ii) ontology integration that brings jargons, terminologies and taxonomies from various disciplines into a unified network of ontologies; (iii) knowledge integration that integrates disparate knowledge elements from multiple sources; (iv) service integration that build applications out of services provided by different vendors. We argue that IB can benefit significantly from the integration solutions enabled by Semantic Web (SW) technologies. The SW enables scientists to share content beyond the boundaries of applications and websites, resulting into a web of data that is meaningful and understandable to any computers. In this review, we provide insight into how SW technologies can be used to build open, standardized and interoperable solutions for interdisciplinary integration on a global basis. We present a rich set of case studies in system biology, integrative neuroscience, bio-pharmaceutics and translational medicine, to highlight the technical features and benefits of SW applications in IB.
Elements of a nitrogen budget for a stream collector. Appendix IX
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1979-01-01
A simple diagram of a preliminary nitrogen budget for a generalized collector-gatherer is presented. The internal anatomy of chironomus sp. indicates its potential for fairly complex physiological processes. 26 refs., 2 figs.
Heix, J; Zomerdijk, J C; Ravanpay, A; Tjian, R; Grummt, I
1997-03-04
Promoter selectivity for all three classes of eukaryotic RNA polymerases is brought about by multimeric protein complexes containing TATA box binding protein (TBP) and specific TBP-associated factors (TAFs). Unlike class II- and III-specific TBP-TAF complexes, the corresponding murine and human class I-specific transcription initiation factor TIF-IB/SL1 exhibits a pronounced selectivity for its homologous promoter. As a first step toward understanding the molecular basis of species-specific promoter recognition, we cloned the cDNAs encoding the three mouse pol I-specific TBP-associated factors (TAFIs) and compared the amino acid sequences of the murine TAFIs with their human counterparts. The four subunits from either species can form stable chimeric complexes that contain stoichiometric amounts of TBP and TAFIs, demonstrating that differences in the primary structure of human and mouse TAFIs do not dramatically alter the network of protein-protein contacts responsible for assembly of the multimeric complex. Thus, primate vs. rodent promoter selectivity mediated by the TBP-TAFI complex is likely to be the result of cumulative subtle differences between individual subunits that lead to species-specific properties of RNA polymerase I transcription.
A Role for Small Antibody Fragments to Bind and Neutralize HIV | Center for Cancer Research
The surface of the Human Immunodeficiency Virus (HIV) is studded with numerous copies of the glycoprotein Env. Each Env spike is composed of three copies of the proteins gp41, which sits in the viral membrane, and gp120, which rests on top of each gp41 molecule. Env is essential for HIV-mediated infection because the binding of gp120 to the T cell surface receptor CD4 initiates a conformational change in Env exposing the fusion peptide, which inserts into the T cell membrane and helps fuse the T cell and virus together. This makes Env an attractive target for designing therapeutic inhibitory antibodies. However, the complexities of the HIV surface proteins and the tight association of the virus and T cell during infection have hampered the identification of full-length antibodies with effective HIV neutralizing activity.
Texture segmentation by genetic programming.
Song, Andy; Ciesielski, Vic
2008-01-01
This paper describes a texture segmentation method using genetic programming (GP), which is one of the most powerful evolutionary computation algorithms. By choosing an appropriate representation texture, classifiers can be evolved without computing texture features. Due to the absence of time-consuming feature extraction, the evolved classifiers enable the development of the proposed texture segmentation algorithm. This GP based method can achieve a segmentation speed that is significantly higher than that of conventional methods. This method does not require a human expert to manually construct models for texture feature extraction. In an analysis of the evolved classifiers, it can be seen that these GP classifiers are not arbitrary. Certain textural regularities are captured by these classifiers to discriminate different textures. GP has been shown in this study as a feasible and a powerful approach for texture classification and segmentation, which are generally considered as complex vision tasks.
Lossi, Nadine S.; Manoli, Eleni; Förster, Andreas; Dajani, Rana; Pape, Tillmann; Freemont, Paul; Filloux, Alain
2013-01-01
Protein secretion systems in Gram-negative bacteria evolved into a variety of molecular nanomachines. They are related to cell envelope complexes, which are involved in assembly of surface appendages or transport of solutes. They are classified as types, the most recent addition being the type VI secretion system (T6SS). The T6SS displays similarities to bacteriophage tail, which drives DNA injection into bacteria. The Hcp protein is related to the T4 bacteriophage tail tube protein gp19, whereas VgrG proteins structurally resemble the gp27/gp5 puncturing device of the phage. The tube and spike of the phage are pushed through the bacterial envelope upon contraction of a tail sheath composed of gp18. In Vibrio cholerae it was proposed that VipA and VipB assemble into a tail sheathlike structure. Here we confirm these previous data by showing that HsiB1 and HsiC1 of the Pseudomonas aeruginosa H1-T6SS assemble into tubules resulting from stacking of cogwheel-like structures showing predominantly 12-fold symmetry. The internal diameter of the cogwheels is ∼100 Å, which is large enough to accommodate an Hcp tube whose external diameter has been reported to be 85 Å. The N-terminal 212 residues of HsiC1 are sufficient to form a stable complex with HsiB1, but the C terminus of HsiC1 is essential for the formation of the tubelike structure. Bioinformatics analysis suggests that HsiC1 displays similarities to gp18-like proteins in its C-terminal region. In conclusion, we provide further structural and mechanistic insights into the T6SS and show that a phage sheathlike structure is likely to be a conserved element across all T6SSs. PMID:23341461
NASA Astrophysics Data System (ADS)
Hudson, R. E.; Holder, A. J.; Hawkins, K. M.; Williams, P. R.; Curtis, D. J.
2017-12-01
The rheological characterisation of viscoelastic materials undergoing a sol-gel transition at the Gel Point (GP) has important applications in a wide range of industrial, biological, and clinical environments and can provide information regarding both kinetic and microstructural aspects of gelation. The most rigorous basis for identifying the GP involves exploiting the frequency dependence of the real and imaginary parts of the complex shear modulus of the critical gel (the system at the GP) measured under small amplitude oscillatory shear conditions. This approach to GP identification requires that rheological data be obtained over a range of oscillatory shear frequencies. Such measurements are limited by sample mutation considerations (at low frequencies) and, when experiments are conducted using combined motor-transducer (CMT) rheometers, by instrument inertia considerations (at high frequencies). Together, sample mutation and inertia induced artefacts can lead to significant errors in the determination of the GP. Overcoming such artefacts is important, however, as the extension of the range of frequencies available to the experimentalist promises both more accurate GP determination and the ability to study rapidly gelling samples. Herein, we exploit the frequency independent viscoelastic properties of the critical gel to develop and evaluate an enhanced rheometer inertia correction procedure. The procedure allows acquisition of valid GP data at previously inaccessible frequencies (using CMT rheometers) and is applied in a study of the concentration dependence of bovine gelatin gelation GP parameters. A previously unreported concentration dependence of the stress relaxation exponent (α) for critical gelatin gels has been identified, which approaches a limiting value (α = 0.7) at low gelatin concentrations, this being in agreement with previous studies and theoretical predictions for percolating systems at the GP.
Distinct Stabilities of the Structurally Homologous Heptameric Co-Chaperonins GroES and gp31
NASA Astrophysics Data System (ADS)
Dyachenko, Andrey; Tamara, Sem; Heck, Albert J. R.
2018-05-01
The GroES heptamer is the molecular co-chaperonin that partners with the tetradecamer chaperonin GroEL, which assists in the folding of various nonnative polypeptide chains in Escherichia coli. Gp31 is a structural and functional analogue of GroES encoded by the bacteriophage T4, becoming highly expressed in T4-infected E. coli, taking over the role of GroES, favoring the folding of bacteriophage proteins. Despite being slightly larger, gp31 is quite homologous to GroES in terms of its tertiary and quaternary structure, as well as in its function and mode of interaction with the chaperonin GroEL. Here, we performed a side-by-side comparison of GroES and gp31 heptamer complexes by (ion mobility) tandem mass spectrometry. Surprisingly, we observed quite distinct fragmentation mechanisms for the GroES and gp31 heptamers, whereby GroES displays a unique and unusual bimodal charge distribution in its released monomers. Not only the gas-phase dissociation but also the gas-phase unfolding of GroES and gp31 were found to be very distinct. We rationalize these observations with the similar discrepancies we observed in the thermal unfolding characteristics and surface contacts within GroES and gp31 in the solution. From our data, we propose a model that explains the observed simultaneous dissociation pathways of GroES and the differences between GroES and gp31 gas-phase dissociation and unfolding. We conclude that, although GroES and gp31 exhibit high homology in tertiary and quaternary structure, they are quite distinct in their solution and gas-phase (un)folding characteristics and stability. [Figure not available: see fulltext.
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Ortega, Angel L; Carretero, Julian; Obrador, Elena; Gambini, Juan; Asensi, Miguel; Rodilla, Vicente; Estrela, José M
2003-04-18
High GSH content associates with high metastatic activity in B16-F10 melanoma cells cultured to low density (LD B16M). GSH homeostasis was investigated in LD B16M cells that survive after adhesion to the hepatic sinusoidal endothelium (HSE). Invasive B16M (iB16M) cells were isolated using anti-Met-72 monoclonal antibodies and flow cytometry-coupled cell sorting. HSE-derived NO and H(2)O(2) caused GSH depletion and a decrease in gamma-glutamylcysteine synthetase activity in iB16M cells. Overexpression of gamma-glutamylcysteine synthetase heavy and light subunits led to a rapid recovery of cytosolic GSH, whereas mitochondrial GSH (mtGSH) further decreased during the first 18 h of culture. NO and H(2)O(2) damaged the mitochondrial system for GSH uptake (rates in iB16M were approximately 75% lower than in LD B16M cells). iB16M cells also showed a decreased activity of mitochondrial complexes II, III, and IV, less O(2) consumption, lower ATP levels, higher O(2) and H(2)O(2) production, and lower mitochondrial membrane potential. In vitro growing iB16M cells maintained high viability (>98%) and repaired HSE-induced mitochondrial damages within 48 h. However, iB16M cells with low mtGSH levels were highly susceptible to TNF-alpha-induced oxidative stress and death. Therefore depletion of mtGSH levels may represent a critical target to challenge survival of invasive cancer cells.
Aspects of the non-pharmacological treatment of irritable bowel syndrome
Eriksson, Elsa Maria; Andrén, Kristina Ingrid; Kurlberg, Göran Karl; Eriksson, Henry Ture
2015-01-01
Irritable bowel syndrome (IBS) is one of the most commonly diagnosed gastrointestinal conditions. It represents a significant healthcare burden and remains a clinical challenge. Over the years IBS has been described from a variety of different perspectives; from a strict illness of the gastrointestinal tract (medical model) to a more complex multi-symptomatic disorder of the brain-gut axis (biopsychosocial/psychosomatic model). In this article we present aspects of the pathophysiology and the non-pharmacological treatment of IBS based on current knowledge. Effects of conditioned stress and/or traumatic influences on the emotional system (top-down) as well as effects on the intestine through stressors, infection, inflammation, food and dysbiosis (bottom-up) can affect brain-gut communication and result in dysregulation of the autonomic nervous system (ANS), playing an important role in the pathophysiology of IBS. Conditioned stress together with dysregulation of the autonomic nervous system and the emotional system may involve reactions in which the distress inside the body is not recognized due to low body awareness. This may explain why patients have difficulty identifying their symptoms despite dysfunction in muscle tension, movement patterns, and posture and biochemical functions in addition to gastrointestinal symptoms. IBS shares many features with other idiopathic conditions, such as fibromyalgia, chronic fatigue syndrome and somatoform disorders. The key to effective treatment is a thorough examination, including a gastroenterological examination to exclude other diseases along with an assessment of body awareness by a body-mind therapist. The literature suggests that early interdisciplinary diagnostic co-operation between gastroenterologists and body-mind therapists is necessary. Re-establishing balance in the ANS is an important component of IBS treatment. This article discusses the current knowledge of body-mind treatment, addressing the topic from a practical point of view. PMID:26523108
Gudleski, Gregory D; Satchidanand, Nikhil; Dunlap, Laura J; Tahiliani, Varnita; Li, Xiaohua; Keefer, Laurie; Lackner, Jeffrey M
2017-01-01
Because health care demand among IBS patients imposes a heavy economic burden, identifying high utilizers has potential for improving quality and efficiency of care. Previous research has not identified reliable predictors of utilization of IBS patients. We sought to identify factors predictive of health care utilization among severe IBS patients. 291 IBS patients completed testing whose content mapped onto the Andersen model of health care utilization. 2-stage hurdle models were used to determine predictors of health care use (probability and frequency). Separate analyses were conducted for mental health and medical services. Whether patients used any medical care was predicted by diet and insurance status. Tobacco use, education, and health insurance predicted the probability of using mental health care. The frequency of medical care was associated with alcohol use and physical health status, while frequency of mental health services was associated with marital status, tobacco use, education, distress, stress, and control beliefs over IBS symptoms. For IBS patients, the demand for health care involves a complex decision-making process influenced by many factors. Particularly strong determinants include predisposing characteristics (e.g., dietary pattern, tobacco use) and enabling factors (e.g., insurance coverage) that impede or facilitate demand. Which factors impact use depends on whether the focus is on the decision to use care or how much care is used. Decisions to use medical and mental health care are not simply influenced by symptom-specific factors but by a variety of lifestyle (e.g., dietary pattern, education, smoking) and economic (e.g., insurance coverage) factors. Copyright © 2016 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kirschner, Austin N.; Sorem, Jessica; Longnecker, Richard
Epstein-Barr virus requires glycoproteins gH/gL, gB, and gp42 to fuse its lipid envelope with B cells. Gp42 is a type II membrane protein consisting of a flexible N-terminal region, which binds gH/gL, and a C-terminal lectin-like domain that binds to the B-cell entry receptor human leukocyte antigen (HLA) class II. Gp42 triggers membrane fusion after HLA binding, a process that requires simultaneous binding to gH/gL and a functional hydrophobic pocket in the lectin domain adjacent to the HLA binding site. Here we present the structure of gp42 in its unbound form. Comparisons to the previously determined structure of a gp42:HLAmore » complex reveals additional N-terminal residues forming part of the gH/gL binding site and structural changes in the receptor binding domain. Although the core of the lectin domain remains similar, significant shifts in two loops and an {alpha} helix bordering the essential hydrophobic pocket suggest a structural mechanism for triggering fusion.« less
Convergent immunological solutions to Argentine hemorrhagic fever virus neutralization.
Zeltina, Antra; Krumm, Stefanie A; Sahin, Mehmet; Struwe, Weston B; Harlos, Karl; Nunberg, Jack H; Crispin, Max; Pinschewer, Daniel D; Doores, Katie J; Bowden, Thomas A
2017-07-03
Transmission of hemorrhagic fever New World arenaviruses from their rodent reservoirs to human populations poses substantial public health and economic dangers. These zoonotic events are enabled by the specific interaction between the New World arenaviral attachment glycoprotein, GP1, and cell surface human transferrin receptor (hTfR1). Here, we present the structural basis for how a mouse-derived neutralizing antibody (nAb), OD01, disrupts this interaction by targeting the receptor-binding surface of the GP1 glycoprotein from Junín virus (JUNV), a hemorrhagic fever arenavirus endemic in central Argentina. Comparison of our structure with that of a previously reported nAb complex (JUNV GP1-GD01) reveals largely overlapping epitopes but highly distinct antibody-binding modes. Despite differences in GP1 recognition, we find that both antibodies present a key tyrosine residue, albeit on different chains, that inserts into a central pocket on JUNV GP1 and effectively mimics the contacts made by the host TfR1. These data provide a molecular-level description of how antibodies derived from different germline origins arrive at equivalent immunological solutions to virus neutralization.
Pregnancy and Irritable Bowel Syndrome
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Sleep and Irritable Bowel Syndrome
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Morandi, Fabio; Airoldi, Irma; Pistoia, Vito
2014-01-01
HLA-G and HLA-E are HLA-Ib molecules with several immunoregulatory properties. Their cell surface expression can be modulated by different cytokines. Since IL-27 and IL-30 may either stimulate or regulate immune responses, we have here tested whether these cytokines may modulate HLA-G and -E expression and function on human monocytes. Monocytes expressed gp130 and WSX-1, the two chains of IL27 receptor (R), and IL6Rα (that serves as IL-30R, in combination with gp130). However, only IL27R appeared to be functional, as witnessed by IL-27 driven STAT1/ STAT3 phosphorylation. IL-27, but not IL-30, significantly upregulated HLA-E (but not HLA-G) expression on monocytes. IFN-γ; secretion by activated NK cells was dampened when the latter cells were cocultured with IL-27 pretreated autologous monocytes. Such effect was not achieved using untreated or IL-30 pretreated monocytes, thus indicating that IL-27 driven HLA-E upregulation might be involved, possibly through the interaction of this molecule with CD94/NKG2A inhibitory receptor on NK cells. In contrast, cytotoxic granules release by NK cell in response to K562 cells was unaffected in the presence of IL-27 pretreated monocytes. In conclusion, we delineated a novel immunoregulatory function of IL-27 involving HLA-E upregulation on monocytes that might in turn indirectly impair some NK cell functions.
Free energy landscapes of RNA/RNA complexes: with applications to snRNA complexes in spliceosomes.
Cao, Song; Chen, Shi-Jie
2006-03-17
We develop a statistical mechanical model for RNA/RNA complexes with both intramolecular and intermolecular interactions. As an application of the model, we compute the free energy landscapes, which give the full distribution for all the possible conformations, for U4/U6 and U2/U6 in major spliceosome and U4atac/U6atac and U12/U6atac in minor spliceosome. Different snRNA experiments found contrasting structures, our free energy landscape theory shows why these structures emerge and how they compete with each other. For yeast U2/U6, the model predicts that the two distinct experimental structures, the four-helix junction structure and the helix Ib-containing structure, can actually coexist and specifically compete with each other. In addition, the energy landscapes suggest possible mechanisms for the conformational switches in splicing. For instance, our calculation shows that coaxial stacking is essential for stabilizing the four-helix junction in yeast U2/U6. Therefore, inhibition of the coaxial stacking possibly by protein-binding may activate the conformational switch from the four-helix junction to the helix Ib-containing structure. Moreover, the change of the energy landscape shape gives information about the conformational changes. We find multiple (native-like and misfolded) intermediates formed through base-pairing rearrangements in snRNA complexes. For example, the unfolding of the U2/U6 undergoes a transition to a misfolded state which is functional, while in the unfolding of U12/U6atac, the functional helix Ib is found to be the last one to unfold and is thus the most stable structural component. Furthermore, the energy landscape gives the stabilities of all the possible (functional) intermediates and such information is directly related to splicing efficiency.
Kim, Kyungho; Li, Jing; Barazia, Andrew; Tseng, Alan; Youn, Seock-Won; Abbadessa, Giovanni; Yu, Yi; Schwartz, Brian; Andrews, Robert K.; Gordeuk, Victor R.; Cho, Jaehyung
2017-01-01
Previous studies identified the Ser/Thr protein kinase, AKT, as a therapeutic target in thrombo-inflammatory diseases. Here we report that specific inhibition of AKT with ARQ 092, an orally-available AKT inhibitor currently in phase Ib clinical trials as an anti-cancer drug, attenuates the adhesive function of neutrophils and platelets from sickle cell disease patients in vitro and cell-cell interactions in a mouse model of sickle cell disease. Studies using neutrophils and platelets isolated from sickle cell disease patients revealed that treatment with 50–500 nM ARQ 092 significantly blocks αMβ2 integrin function in neutrophils and reduces P-selectin exposure and glycoprotein Ib/IX/V-mediated agglutination in platelets. Treatment of isolated platelets and neutrophils with ARQ 092 inhibited heterotypic cell-cell aggregation under shear conditions. Intravital microscopic studies demonstrated that short-term oral administration of ARQ 092 or hydroxyurea, a major therapy for sickle cell disease, diminishes heterotypic cell-cell interactions in venules of sickle cell disease mice challenged with tumor necrosis factor-α. Co-administration of hydroxyurea and ARQ 092 further reduced the adhesive function of neutrophils in venules and neutrophil transmigration into alveoli, inhibited expression of E-selectin and intercellular adhesion molecule-1 in cremaster vessels, and improved survival in these mice. Ex vivo studies in sickle cell disease mice suggested that co-administration of hydroxyurea and ARQ 092 efficiently blocks neutrophil and platelet activation and that the beneficial effect of hydroxyurea results from nitric oxide production. Our results provide important evidence that ARQ 092 could be a novel drug for the prevention and treatment of acute vaso-occlusive complications in patients with sickle cell disease. PMID:27758820
Kibune Nagasako, Cristiane; Garcia Montes, Ciro; Silva Lorena, Sônia Letícia; Mesquita, Maria Aparecida
2016-02-01
Irritable bowel syndrome (IBS) is classified into subtypes according to bowel habit. To investigate whether there are differences in clinical features, comorbidities, anxiety, depression and body mass index (BMI) among IBS subtypes. The study group included 113 consecutive patients (mean age: 48 ± 11 years; females: 94) with the diagnosis of IBS. All of them answered a structured questionnaire for demographic and clinical data and underwent upper endoscopy. Anxiety and depression were assessed by the Hospital Anxiety and Depression scale (HAD). The distribution of subtypes was: IBS-diarrhea (IBS-D), 46%; IBS-constipation (IBS-C), 32%, and mixed IBS (IBS-M), 22%. IBS overlap with gastroesophageal reflux disease (GERD), functional dyspepsia, chronic headache and fibromyalgia occurred in 65.5%, 48.7%, 40.7% and 22.1% of patients, respectively. Anxiety and/or depression were found in 81.5%. Comparisons among subgroups showed that bloating was significantly associated with IBS-M compared to IBS-D (odds ratio-OR-5.6). Straining was more likely to be reported by IBS-M (OR 15.3) and IBS-C (OR 12.0) compared to IBS-D patients, while urgency was associated with both IBS-M (OR 19.7) and IBS-D (OR 14.2) compared to IBS-C. In addition, IBS-M patients were more likely to present GERD than IBS-D (OR 6.7) and higher scores for anxiety than IBS-C patients (OR 1.2). BMI values did not differ between IBS-D and IBS-C. IBS-M is characterized by symptoms frequently reported by both IBS-C (straining) and IBS-D (urgency), higher levels of anxiety, and high prevalence of comorbidities. These features should be considered in the clinical management of this subgroup.
Young Stellar Populations in MYStIX Star-forming Regions: Candidate Protostars
NASA Astrophysics Data System (ADS)
Romine, Gregory; Feigelson, Eric D.; Getman, Konstantin V.; Kuhn, Michael A.; Povich, Matthew S.
2016-12-01
The Massive Young Star-Forming Complex in Infrared and X-ray (MYStIX) project provides a new census on stellar members of massive star-forming regions within 4 kpc. Here the MYStIX Infrared Excess catalog and Chandra-based X-ray photometric catalogs are mined to obtain high-quality samples of Class I protostars using criteria designed to reduce extragalactic and Galactic field star contamination. A total of 1109 MYStIX Candidate Protostars (MCPs) are found in 14 star-forming regions. Most are selected from protoplanetary disk infrared excess emission, but 20% are found from their ultrahard X-ray spectra from heavily absorbed magnetospheric flare emission. Two-thirds of the MCP sample is newly reported here. The resulting samples are strongly spatially associated with molecular cores and filaments on Herschel far-infrared maps. This spatial agreement and other evidence indicate that the MCP sample has high reliability with relatively few “false positives” from contaminating populations. But the limited sensitivity and sparse overlap among the infrared and X-ray subsamples indicate that the sample is very incomplete with many “false negatives.” Maps, tables, and source descriptions are provided to guide further study of star formation in these regions. In particular, the nature of ultrahard X-ray protostellar candidates without known infrared counterparts needs to be elucidated.
Němeček, Daniel; Gilcrease, Eddie B.; Kang, Sebyung; Prevelige, Peter E.; Casjens, Sherwood; Thomas, George J.
2007-01-01
Bacteriophage P22, a podovirus infecting strains of Salmonella typhimurium, packages a 42 kbp genome using a headful mechanism. DNA translocation is accomplished by the phage terminase, a powerful molecular motor consisting of large and small subunits. Although many of the structural proteins of the P22 virion have been well characterized, little is known about the terminase subunits and their molecular mechanism of DNA translocation. We report here structural and assembly properties of ectopically expressed and highly purified terminase large and small subunits. The large subunit (gp2), which contains the nuclease and ATPase activities of terminase, exists as a stable monomer with an α/β fold. The small subunit (gp3), which recognizes DNA for packaging and may regulate gp2 activity, exhibits a highly α-helical secondary structure and self-associates to form a stable oligomeric ring in solution. For wildtype gp3, the ring contains nine subunits, as demonstrated by hydrodynamic measurements, electron microscopy and native mass spectrometry. We have also characterized a gp3 mutant (Ala 112 → Thr) that forms a ten subunit ring, despite a subunit fold indistinguishable from wildtype. Both the nonameric and decameric gp3 rings exhibit nonspecific DNA binding activity, and gp2 is able to bind strongly to the DNA/gp3 complex but not to DNA alone. We propose a scheme for the roles of P22 terminase large and small subunits in the recruitment and packaging of viral DNA and discuss the model in relation to proposals for terminase-driven DNA translocation in other phages. PMID:17945256
DOE Office of Scientific and Technical Information (OSTI.GOV)
Steiner, B.; Cousot, D.; Trzeciak, A.
The platelet glycoprotein IIb-IIIa complex (GP IIb-IIIa) is a member of the integrin receptor family that recognizes adhesive proteins containing the Arg-Gly-Asp (RGD) sequence. In the present study the binding characteristics of the synthetic hexapeptide Tyr-Asn-Arg-Gly-Asp-Ser (YNRGDS, a sequence present in the fibrinogen alpha-chain at position 570-575) to purified GP IIb-IIIa were determined by equilibrium dialysis. The binding of 125I-YNRGDS to GP IIb-IIIa was specific, saturable, and reversible. The apparent dissociation constant was 1.0 +/- 0.2 microM, and the maximal binding capacity was 0.92 +/- 0.02 mol of 125I-YNRGDS/mol of GP IIb-IIIa, indicating that GP IIb-IIIa contains a single bindingmore » site for RGD peptides. The binding of 125I-YNRGDS to purified GP IIb-IIIa showed many of the characteristics of fibrinogen binding to activated platelets: the binding was inhibited by fibrinogen, by the monoclonal antibody A2A9, and by the dodecapeptide from the C terminus of the fibrinogen gamma-chain. In addition, the binding of 125I-YNRGDS to GP IIb-IIIa was divalent cation-dependent. Our data suggest that two divalent cation binding sites must be occupied for YNRGDS to bind: one site is specific for calcium and is saturated at 1 microM free Ca2+, whereas the other site is less specific and reaches saturation at millimolar concentrations of either Ca2+ or Mg2+. The results of the present study support the hypothesis that the RGD domains within the adhesive proteins are responsible for their binding to GP IIb-IIIa.« less
Buijs, Peter C; van Dijk, Frank J H; Evers, Marÿe; vd Klink, Jacques J L; Anema, Han
2007-01-01
Increasingly, workers have psychological work-related complaints, endangering their work ability and causing considerable economic losses. Many employees consult their general practitioner (GP). He, however, often pays insufficient attention to work-relatedness or to coordination with occupational physicians (OPs). Appropriate guidelines are missing. Consequently, we developed a GP guideline to handle these problems in coordination with OPs, and tested it in a pilot, using an explorative, evaluative study design. 23 GPs were trained to include employed patients and to test the guideline. Patients received questionnaires after 0, 4, 10 and 30 wk, GPs after 4 and 30 wk. The result was a new guideline, regarding problem orientation, diagnosis and advice, meant to avoid contradictory GP-OP advice and to activate patient responsibility. It included a GP-OP-patient communication form concerning information exchange and harmonization of insight/advice. Implementing GPs concluded that the guideline promotes recovery and work resumption and OP-GP contact benefits patients, prevents conflicting advice and promotes agreement on task division. They judged guideline efficiency and OP commitment less positively. Patients were positive, especially about GP-OP contact. Accordingly, an improved guideline, when tested for its effectiveness in a Randomized Controlled Trial, can help GPs to cope with a growing, complex problem, in collaboration with their occupational colleagues.
A Methodology to Compare Insulin Dosing Recommendations in Real-Life Settings.
Groat, Danielle; Grando, Maria A; Thompson, Bithika; Neto, Pedro; Soni, Hiral; Boyle, Mary E; Bailey, Marilyn; Cook, Curtiss B
2017-11-01
We propose a methodology to analyze complex real-life glucose data in insulin pump users. Patients with type 1 diabetes (T1D) on insulin pumps were recruited from an academic endocrinology practice. Glucose data, insulin bolus (IB) amounts, and self-reported alcohol consumption and exercise events were collected for 30 days. Rules were developed to retrospectively compare IB recommendations from the insulin pump bolus calculator (IPBC) against recommendations from a proposed decision aid (PDA) and for assessing the PDA's recommendation for exercise and alcohol. Data from 15 participants were analyzed. When considering instances where glucose was below target, the PDA recommended a smaller dose in 14%, but a larger dose in 13% and an equivalent IB in 73%. For glucose levels at target, the PDA suggested an equivalent IB in 58% compared to the subject's IPBC, but higher doses in 20% and lower in 22%. In events where postprandial glucose was higher than target, the PDA suggested higher doses in 25%, lower doses in 13%, and equivalent doses in 62%. In 64% of all alcohol events the PDA would have provided appropriate advice. In 75% of exercise events, the PDA appropriately advised an IB, a carbohydrate snack, or neither. This study provides a methodology to systematically analyze real-life data generated by insulin pumps and allowed a preliminary analysis of the performance of the PDA for insulin dosing. Further testing of the methodological approach in a broader diabetes population and prospective testing of the PDA are needed.
Irritable bowel syndrome in children: Pathogenesis, diagnosis and evidence-based treatment
Sandhu, Bhupinder Kaur; Paul, Siba Prosad
2014-01-01
Irritable bowel syndrome (IBS) is the commonest cause of recurrent abdominal pain (RAP) in children in both more developed and developing parts of the world. It is defined by the Rome III criteria for functional gastrointestinal disorders. It is characterized by abdominal pain that is improved by defecation and whose onset is associated with a change in stool form and or frequency and is not explained by structural or biochemical abnormalities. It is estimated that 10%-15% of older children and adolescents suffer from IBS. IBS can be considered to be a brain-gut disorder possibly due to complex interaction between environmental and hereditary factors. The diagnosis of IBS is made based on the Rome III criteria together with ruling out organic causes of RAP in children such as inflammatory bowel disease and celiac disease. Once the diagnosis of IBS is made, it is important to explain to the parents (and children) that there is no serious underlying disease. This reassurance may be effective treatment in a large number of cases. Lifestyle modifications, stress management, dietary interventions and probiotics may be beneficial in some cases. Although there is limited evidence for efficacy of pharmacological therapies such as antispasmodics and antidiarrheals; these have a role in severe cases. Biopsychosocial therapies have shown encouraging results in initial trials but are beset by limited availability. Further research is necessary to understand the pathophysiology and provide specific focused therapies. PMID:24876724
de Lucio, Aida; Merino, Francisco J; Martínez-Ruiz, Rocío; Bailo, Begoña; Aguilera, María; Fuentes, Isabel; Carmena, David
2016-01-01
Infections by members of the protozoan genus Cryptosporidium are among the most common causes of human gastrointestinal illness worldwide. In Spain cryptosporidiosis is not a compulsory notifiable disease, so the actual burden of the infection in both clinical and general populations remains largely unknown. We present here data on the diversity and frequency of the Cryptosporidium species and sub-genotypes identified in symptomatic individuals seeking medical care in two major hospitals in Madrid, Spain, between December 2013 and January 2015. Initial detection of the parasite was conducted on a total of 122 stool samples collected from 120 patients by microscopy with modified Ziehl-Neelsen and/or immunochromatographic tests. We used immunofluorescence, PCR-based methods and sequence analyses of the 60-kDa (GP60) glycoprotein and the small subunit ribosomal RNA (SSU rRNA) genes for confirmatory purposes and to characterize Cryptosporidium isolates. A total of 110 patients were confirmed with cryptosporidiosis. Overall, 101 isolates were successfully sub-genotyped at the GP60 locus, and an additional seven at the SSU rRNA locus. The analyses of all amplicons defined 10 distinct sequence types representing the GP60 family sub-genotypes IbA10G2 (78.7%), IeA11G3T3 (3.7%) of C. hominis, and the GP60 family sub-types IIaA15G2R1 (5.6%), IIaA18G6R1 (0.9%), IIcA5G3a (0.9%), IIdA18G1 (0.9%), IIdA19G1 (0.9%), IIdA21G1 (0.9%), and IIdA22G1 (0.9%) of C. parvum. A single isolate was assigned to C. felis (0.9%), two C. parvum isolates (1.9%) could not be characterized at the sub-genotype level and an additional four isolates (3.7%) were not typable. These results strongly suggest that transmission of cryptosporidiosis is mostly anthroponotic in origin in the clinical sample under study. We expect that our molecular epidemiological data will make a significant contribution to unravel the actual epidemiological situation of cryptosporidiosis in Spain, providing health care and policy makers with solid baseline information to unavoidably improve the national surveillance system and allocate additional resources to research, diagnosis, and treatment of cryptosporidiosis.
NASA Astrophysics Data System (ADS)
Migliori, Amy; Arya, Gaurav; Smith, Douglas E.
2012-10-01
Bacteriophage T4 is a double stranded DNA virus that infects E.coli by injecting the viral genome through the cellular wall of a host cell. The T4 genome must be ejected from the viral capsid with sufficient force to ensure infection. To generate high ejection forces, the genome is packaged to high density within the viral capsid. A DNA translocation motor, in which the protein gp17 hydrolyzes ATP and binds to the DNA, is responsible for translocating the genome into the capsid during viral maturation of T4. This motor generates forces in excess of 60 pN and packages DNA at rates exceeding 2000 base pairs/second (bp/s)1. Understanding these small yet powerful motors is important, as they have many potential applications. Though much is known about the activity of these motors from bulk and single molecule biophysical techniques, little is known about their detailed molecular mechanism. Recently, two structures of gp17 have been obtained: a high-resolution X-ray crystallographic structure showing a monomeric compacted form of the enzyme, and a cryo-electron microscopic structure of the extended form of gp17 in complex with actively packaging prohead complexes. Comparison of these two structures indicates several key differences, and a model has been proposed to explain the translocation action of the motor2. Key to this model are a set of residues forming ion pairs across two domains of the gp17 molecule that are proposed to be involved in force generation by causing the collapse of the extended form of gp17. Using a dual optical trap to measure the rates of DNA packaging and the generated forces, we present preliminary mutational data showing that these several of these ion pairs are important to motor function. We have also performed preliminary free energy calculations on the extended and collapsed state of gp17, to confirm that these interdomain ion pairs have large contributions to the change in free energy that occurs upon the collapse of gp17 during the proposed ratcheting mechanism.
Control of Bacteriophage T4 Tail Lysozyme Activity During the Infection Process
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kanamaru, Shuji; Ishiwata, Yasutaka; Suzuki, Toshiharu
2010-07-19
Bacteriophage T4 has an efficient mechanism for injecting the host Escherichia coli cell with genomic DNA. Its gene product 5 (gp5) has a needle-like structure attached to the end of a tube through which the DNA passes on its way out of the head and into the host. The gp5 needle punctures the outer cell membrane and then digests the peptidoglycan cell wall in the periplasmic space. gp5 is normally post-translationally cleaved between residues 351 and 352. The function of this process in controlling the lysozyme activity of gp5 has now been investigated. When gp5 is over-expressed in E. coli,more » two mutants (S351H and S351A) showed a reduction of cleavage products and five other mutants (S351L, S351K, S351Y, S351Q, and S351T) showed no cleavage. Furthermore, in a complementation assay at 20 C, the mutants that had no cleavage of gp5 produced a reduced number of plaques compared to wild-type T4. The crystal structure of the non-cleavage phenotype mutant of gp5, S351L, complexed with gene product 27, showed that the 18 residues in the vicinity of the potential cleavage site (disordered in the wild-type structure) had visible electron density. The polypeptide around the potential cleavage site is exposed, thus allowing access for an E. coli protease. The lysozyme activity is inhibited in the wild-type structure by a loop from the adjacent gp5 monomer that binds into the substrate-binding site. The same inhibition is apparent in the mutant structure, showing that the lysozyme is inhibited before gp5 is cleaved and, presumably, the lysozyme is activated only after gp5 has penetrated the outer membrane.« less
The anti-tumor effect and mechanisms of action of penta-acetyl geniposide.
Peng, C H; Huang, C N; Wang, C J
2005-06-01
Gardenia, the fruit of Gardenia jasminoides Ellis, has been widely used to treat liver and gall bladder disorders in Chinese medicine. It has been shown recently that geniposide, the main ingredient of Gardenia Fructus, exhibits the anti-tumor effect. In this review, we discuss the anti-tumor effect and possible mechanisms of a derivative from Gardenia Fructus, penta-acetyl geniposide ((Ac)5GP). It has been demonstrated that (Ac)5GP plays more potent roles than geniposide in chemoprevention. (Ac)5GP decreased DNA damage and hepatocarcinogenesis induced by aflatoxin B1 (AFB1) by activating the phase II enzymes glutathione S-transferase (GST) and GSH peroxidase (GSH-Px). It reduced the growth and development of inoculated C6 glioma cells especially in pre-treated rats. In addition to the preventive effect, (Ac)5GP exerts its actions on apoptosis and growth arrest. Treatment of (Ac)5GP caused DNA fragmentation of glioma cells. (Ac)5GP induced sub- G1 peak through the activation of apoptotic cascades PKCdelta/JNK/Fas/caspase8 and caspase 3. Besides, p53/Bax signaling was suggested to be involved in (Ac)5GP-induced apoptosis, though its downstream cascades needs further clarified. (Ac)5GP has also been shown to inhibit DNA synthesis of tumor cells. It arrested cell cycle at G0/ G1 by inducing the expression of p21, thus suppressing the cyclin D1/cdk4 complex formation and the phosphorylation of E2F. The phosphorylation status of p53 on serine 392 correlated with the process of growth arrest. Evidences from the in vivo experiments showed that (Ac)5GP is not harmful to liver, heart and kidney. In conclusion, (Ac)5GP is highly suggested to be an anti-tumor agent for development in the future.
Mdm2 mediates FMRP- and Gp1 mGluR-dependent protein translation and neural network activity.
Liu, Dai-Chi; Seimetz, Joseph; Lee, Kwan Young; Kalsotra, Auinash; Chung, Hee Jung; Lu, Hua; Tsai, Nien-Pei
2017-10-15
Activating Group 1 (Gp1) metabotropic glutamate receptors (mGluRs), including mGluR1 and mGluR5, elicits translation-dependent neural plasticity mechanisms that are crucial to animal behavior and circuit development. Dysregulated Gp1 mGluR signaling has been observed in numerous neurological and psychiatric disorders. However, the molecular pathways underlying Gp1 mGluR-dependent plasticity mechanisms are complex and have been elusive. In this study, we identified a novel mechanism through which Gp1 mGluR mediates protein translation and neural plasticity. Using a multi-electrode array (MEA) recording system, we showed that activating Gp1 mGluR elevates neural network activity, as demonstrated by increased spontaneous spike frequency and burst activity. Importantly, we validated that elevating neural network activity requires protein translation and is dependent on fragile X mental retardation protein (FMRP), the protein that is deficient in the most common inherited form of mental retardation and autism, fragile X syndrome (FXS). In an effort to determine the mechanism by which FMRP mediates protein translation and neural network activity, we demonstrated that a ubiquitin E3 ligase, murine double minute-2 (Mdm2), is required for Gp1 mGluR-induced translation and neural network activity. Our data showed that Mdm2 acts as a translation suppressor, and FMRP is required for its ubiquitination and down-regulation upon Gp1 mGluR activation. These data revealed a novel mechanism by which Gp1 mGluR and FMRP mediate protein translation and neural network activity, potentially through de-repressing Mdm2. Our results also introduce an alternative way for understanding altered protein translation and brain circuit excitability associated with Gp1 mGluR in neurological diseases such as FXS. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kwon, Young Do; Finzi, Andrés; Wu, Xueling
2013-03-04
The HIV-1 envelope (Env) spike (gp120{sub 3}/gp41{sub 3}) undergoes considerable structural rearrangements to mediate virus entry into cells and to evade the host immune response. Engagement of CD4, the primary human receptor, fixes a particular conformation and primes Env for entry. The CD4-bound state, however, is prone to spontaneous inactivation and susceptible to antibody neutralization. How does unliganded HIV-1 maintain CD4-binding capacity and regulate transitions to the CD4-bound state? To define this mechanistically, we determined crystal structures of unliganded core gp120 from HIV-1 clades B, C, and E. Notably, all of these unliganded HIV-1 structures resembled the CD4-bound state. Conformationalmore » fixation with ligand selection and thermodynamic analysis of full-length and core gp120 interactions revealed that the tendency of HIV-1 gp120 to adopt the CD4-bound conformation was restrained by the V1/V2- and V3-variable loops. In parallel, we determined the structure of core gp120 in complex with the small molecule, NBD-556, which specifically recognizes the CD4-bound conformation of gp120. Neutralization by NBD-556 indicated that Env spikes on primary isolates rarely assume the CD4-bound conformation spontaneously, although they could do so when quaternary restraints were loosened. Together, the results suggest that the CD4-bound conformation represents a 'ground state' for the gp120 core, with variable loop and quaternary interactions restraining unliganded gp120 from 'snapping' into this conformation. A mechanism of control involving deformations in unliganded structure from a functionally critical state (e.g., the CD4-bound state) provides advantages in terms of HIV-1 Env structural diversity and resistance to antibodies and inhibitors, while maintaining elements essential for entry.« less
Iikuni, Shimpei; Ono, Masahiro; Watanabe, Hiroyuki; Shimizu, Yoichi; Sano, Kohei; Saji, Hideo
2018-01-01
Hypoxic cells dynamically translocate during tumor growth and after radiotherapy. The most desirable direction for therapy targeting hypoxic cells is combining imaging and therapy (theranostics), which may help realize personalized medicine. Here, we conducted cancer radiotheranostics targeting carbonic anhydrase-IX (CA-IX), which is overexpressed in many kinds of hypoxic cancer cells, using low-molecular-weight 111In and 90Y complexes with a bivalent ureidosulfonamide scaffold as the CA-IX-binding moiety ([111In/90Y]US2). Methods: The targeting ability of [111In]US2 was evaluated by in vivo biodistribution study in CA-IX high-expressing (HT-29) tumor-bearing mice. In vivo imaging of HT-29 tumors was carried out using single photon emission computed tomography (SPECT). [90Y]US2 was administered to HT-29 tumor-bearing mice to evaluate cancer therapeutic effects. Results: [111In]US2 highly and selectively accumulated within HT-29 tumors (4.57% injected dose/g tumor at 1 h postinjection), was rapidly cleared from the blood pool and muscle after 4 h based on a biodistribution study, and visualized HT-29 tumor xenografts in mice at 4 h postinjection with SPECT. Radionuclide-based therapy with [90Y]US2 significantly delayed HT-29 tumor growth compared with that of untreated mice (P = 0.02 on day 28, Student's t-test), without any critical hematological toxicity due to its rapid pharmacokinetics. Conclusion: These results indicate that cancer radiotheranostics with [111In/90Y]US2 provides a novel strategy of theranostics for cancer hypoxia.
Bru, T; Vila, R; Cabana, M; Geerligs, H J
2017-02-01
Infectious bronchitis virus (IBV) is a coronavirus which affects chickens of all ages. IBV mainly causes respiratory disease but can also result in reduced weight gain, reduced egg production, increased frequency of abnormal eggs and increased rates of mortality. Vaccination is the most important way to control the disease. Nevertheless, novel strains of infectious bronchitis (IB) continue to emerge in the field. In order to respond promptly, combinations of existing IB vaccines are frequently tested to see whether they can provide cross-protection. The efficacy of a combination of vaccines based on Massachusetts, Dutch and QX-like IB strains against emerging IB Israel variant 2 and IB 793B strains was assessed by means of four challenge studies. At least 80% of the birds vaccinated with IB H120 (Mass type) combined with IB D274 (Dutch type) followed by a QX-like IB vaccine booster or vaccinated with a combination of IB H120, IB D274 and QX-like IB were protected against a challenge with IB 793B. In addition, IB 1263 (Mass type) boosted by QX-like IB showed an 85% protection following challenge with IB 793B. A combination of IB H120 and IB D274 boosted by QX-like IB vaccine conferred 70% protection whilst H120 and IB D274 combination on its own showed 61.1% protection against Israel variant 2 challenge. IB 1263 boosted by a QX-like IB vaccine showed 50% protection against IB Israel variant 2. Therefore, it can be concluded that a combination of the IB H120, IB D274 and QX-like IB confers broad protection against different non-related virulent IB strains.
A nanovehicle developed for treating deep-seated bacteria using low-dose X-ray.
Pan, Chien-Lin; Chen, Ming-Hong; Tung, Fu-I; Liu, Tse-Ying
2017-01-01
Many non-antibiotic strategies, such as photocatalysis and photodynamic therapy, have been proposed to inhibit and/or kill bacteria. However, these approaches still have drawbacks such as insufficient bacterial specificity and the limited penetration depth of ultraviolet and near-infrared light. To overcome these limitations, we developed a bacteria-specific anti-bacterial technique via using low-dose X-ray. Graphene oxide quantum dots (GQDs, a multifunctional vehicle) conjugated with vancomycin (Van, a bacteria-targeting ligand) were assembled with Protoporphyrin IX (PpIX, a photo/radiation sensitizer) to yield a novel Van-GQDs/PpIX complex that specifically attached to Escherichia coli and efficiently generated intracellular reactive oxygen species following X-ray activation. Delivery using GQDs increased the PpIX/Van ratio in the target bacterial cell, damaged bacterial cell wall, and enhanced X-ray-induced PpIX activation. Hence, this approach allowed for the use of a low-dose X-ray to efficiently activate the Van-GQDs/PpIX complex to exert its bactericidal effects on Escherichia coli without damaging normal cells. Furthermore, the E. coli did not develop resistance to the proposed approach for at least 7 rounds of repeated administration during one week. Thus, this proposed vehicle exhibiting bacteria-specific X-ray-triggered toxicity is a promising alternative to antibiotics for treating serious bacterial infections occurring in deep-seated tissues/organs (e.g., osteomyelitis and peritonitis). Administration of antibiotics is the most common treatment modality for bacterial infections. However, in some cases, patient attributes such as age, health, tolerance to antibiotics do not allow for the use of high-dose antibiotics. In addition, some bacteria develop resistance to antibiotics because of improper and long-term use of these agents. Therefore, non-antibiotic strategies to treat deeply situated bacterial infections, such as osteomyelitis, are urgently needed for avoiding amputation. To date, several non-antibiotic approaches, such as Ag nanoparticles, graphene-based materials, photocatalysis, and photodynamic therapy have been proposed to inhibit and/or kill bacteria. However, the major challenges of photochemical strategies, specificity and limited penetration depth of light source, still remain for treating the deep-seated bacteria. To overcome these problems, we developed a novel nanovehicle that exerted toxic effects specifically on bacteria following activation by a deeply penetrative low-dose X-ray, without damaging normal cells. As such, it realizes a deeply photochemical route for treating the deep-seated bacteria. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Ares I-X Flight Test Development Challenges and Success Factors
NASA Technical Reports Server (NTRS)
Askins, Bruce; Davis, Steve; Olsen, Ronald; Taylor, James
2010-01-01
The NASA Constellation Program's Ares I-X rocket launched successfully on October 28, 2009 collecting valuable data and providing risk reduction for the Ares I project. The Ares I-X mission was formulated and implemented in less than four years commencing with the Exploration Systems Architecture Study in 2005. The test configuration was founded upon assets and processes from other rocket programs including Space Shuttle, Atlas, and Peacekeeper. For example, the test vehicle's propulsion element was a Shuttle Solid Rocket Motor. The Ares I-X rocket comprised a motor assembly, mass and outer mold line simulators of the Ares I Upper Stage, Orion Spacecraft and Launch Abort System, a roll control system, avionics, and other miscellaneous components. The vehicle was 327 feet tall and weighed approximately 1,800,000 pounds. During flight the rocket reached a maximum speed of Mach 4.8 and an altitude of 150,000 feet. The vehicle demonstrated staging at 130,000 feet, tested parachutes for recovery of the motor, and utilized approximately 900 sensors for data collection. Developing a new launch system and preparing for a safe flight presented many challenges. Specific challenges included designing a system to withstand the environments, manufacturing large structures, and re-qualifying heritage hardware. These and other challenges, if not mitigated, may have resulted in test cancellation. Ares I-X succeeded because the mission was founded on carefully derived objectives, led by decisive and flexible management, implemented by an exceptionally talented and dedicated workforce, and supported by a thorough independent review team. Other major success factors include the use of proven heritage hardware, a robust System Integration Laboratory, multi-NASA center and contractor team, concurrent operations, efficient vehicle assembly, effective risk management, and decentralized element development with a centralized control board. Ares I-X was a technically complex test that required creative thinking, risk taking, and a passion to succeed.
Singh, Prashant; Staller, Kyle; Barshop, Kenneth; Dai, Elaine; Newman, Jennifer; Yoon, Sonia; Castel, Shahar; Kuo, Braden
2015-01-01
AIM: To determine effect of irritable bowel syndrome (IBS) subtype on IBS-specific quality of life (QOL) questionnaire and its subscales. METHODS: We studied IBS patients visiting our functional gastroenterology disorder clinic at a tertiary care center of Unites States. IBS and IBS subtype were diagnosed using Rome-III questionnaire. QOL was assessed using IBS-QOL questionnaire. IBS-QOL assesses quality of life along eight subscales: dysphoria, interference with activities, body image, health worry, food avoidance, social reactions, sexual health, and effect on relationships. IBS-QOL and its subscales were both scored on a range of 0-100 with higher scores suggestive of better QOL. Results of overall IBS-QOL scores and subscale scores are expressed as means with 95%CI. We compared mean IBS-QOL score and its subscales among various IBS-subtypes. Analysis of variance (ANOVA) was used to compare the mean difference between more than two groups after controlling for age and gender. A post-hoc analysis using Bonferroni correction was used only when P value for ANOVA was less than 0.05. RESULTS: Of 542 patients screened, 243 had IBS as per Rome-III criteria. IBS-mixed (IBS-M) was the most common IBS subtype (121 patients, 49.8%) followed by IBS- diarrhea (IBS-D) (56 patients, 23.1%), IBS-constipation (IBS-C) (54 patients, 22.2%) and IBS-unspecified (IBS-U) (12 patients, 4.9%). Overall IBS-QOL scores were significantly different among various IBS-subtypes (P = 0.01). IBS-QOL of patients with IBS-D (61.6, 95%CI: 54.0-69.1) and IBS-M (63.0, 95%CI: 58.1-68.0) was significantly lower than patients with IBS-C (74.5, 95%CI: 66.9-82.1) (P = 0.03 and 0.02 respectively). IBS-D patients scored significantly lower than IBS-C on food avoidance (45.0, 95%CI: 34.8-55.2 vs 61.1, 95%CI: 50.8-71.3, P = 0.04) and interference with activity (59.6, 95%CI: 51.4-67.7 vs 82.3, 95%CI: 74.1-90.6, P < 0.001). IBS-M patients had more interference in their activities (61.6, 95%CI: 56.3-66.9 vs 82.3, 95%CI: 74.1-90.6, P = 0.001) and greater impact on their relationships (73.3, 95%CI: 68.4-78.2 vs 84.7, 95%CI: 77.2-92.2, P = 0.02) than IBS-C patients. Patients with IBS-M also scored significantly lower than IBS-C on food avoidance (47.2, 95%CI: 40.7-53.7 vs 61.1, 95%CI: 50.8-71.3, P = 0.04) and social reaction (66.1, 95%CI: 61.1-71.1 vs 80.0, 95%CI: 72.1-87.7, P = 0.005). CONCLUSION: IBS-D and IBS-M patients have lower IBS-QOL than IBS-C patients. Clinicians should recognize food avoidance, effects on daily activities and relationship problems in these patients. PMID:26185382
Jiang, Yunbo; Xiao, Shaobo; Fang, Liurong; Yu, Xiaolan; Song, Yunfeng; Niu, Chuanshuang; Chen, Huanchun
2006-04-05
The two major membrane-associated proteins of porcine reproductive and respiratory syndrome virus (PRRSV), GP5 and M (encoded by ORF5 and ORF6 genes, respectively), are associated as disulfide-linked heterodimers (GP5/M) in the virus particle. In the present study, three different DNA vaccine constructs, expressing GP5 alone (pCI-ORF5), M alone (pCI-ORF6) or GP5 and M proteins simultaneously (pCI-ORF5/ORF6), were constructed. In vitro, the co-expressed GP5 and M proteins could form heterodimeric complexes in transfected cells and heterodimerization altered the subcellular localization of GP5. The immunogenicities of these DNA vaccine constructs were firstly investigated in a mouse model. Mice inoculated with pCI-ORF5/ORF6 developed PRRSV-specific neutralizing antibodies at 6 and 8 weeks after primary immunization. However, only some mice developed low levels of neutralizing antibodies in groups immunized with pCI-ORF5 or pCI-ORF6. The highest lymphocyte proliferation responses were also observed in mice immunized with pCI-ORF5/ORF6. Interestingly, significantly enhanced GP5-specific ELISA antibody could be detected in mice immunized with pCI-ORF5/ORF6 compared to mice immunized with pCI-ORF5. The immunogenicities of pCI-ORF5/ORF6 were further evaluated in piglets (the natural host) and all immunized piglets developed neutralizing antibodies at 10 weeks after primary immunization, whereas there was no detectable neutralizing antibodies in piglets immunized with pCI-ORF5. These results indicate that the formation of GP5/M heterodimers may be involved in post-translational modification and transport of GP5 and may play an important role in immune responses against PRRSV infection. More importantly, co-expression of GP5 and M protein in heterodimers can significantly improve the potency of DNA vaccination and could be used as a strategy to develop a new generation of vaccines against PRRSV.
Butyric acid in irritable bowel syndrome.
Załęski, Andrzej; Banaszkiewicz, Aleksandra; Walkowiak, Jarosław
2013-01-01
Butyric acid (butanoic acid) belongs to a group of short-chain fatty acids and is thought to play several beneficial roles in the gastrointestinal tract. Butyric anion is easily absorbed by enteric cells and used as a main source of energy. Moreover, butyric acid is an important regulator of colonocyte proliferation and apoptosis, gastrointestinal tract motility and bacterial microflora composition in addition to its involvement in many other processes including immunoregulation and anti-inflammatory activity. The pathogenesis of irritable bowel syndrome (IBS), the most commonly diagnosed functional gastrointestinal condition, is complex, and its precise mechanisms are still unclear. This article describes the potential benefits of butyric acid in IBS.
Structure and mechanism of the phage T4 recombination mediator protein UvsY
Gajewski, Stefan; Waddell, Michael Brett; Vaithiyalingam, Sivaraja; ...
2016-03-07
The UvsY recombination mediator protein is critical for efficient homologous recombination in bacteriophage T4 and is the functional analog of the eukaryotic Rad52 protein. During T4 homologous recombination, the UvsX recombinase has to compete with the prebound gp32 single-stranded binding protein for DNA-binding sites and UvsY stimulates this filament nucleation event. We report here the crystal structure of UvsY in four similar open-barrel heptameric assemblies and provide structural and biophysical insights into its function. The UvsY heptamer was confirmed in solution by centrifugation and light scattering, and thermodynamic analyses revealed that the UvsY–ssDNA interaction occurs within the assembly via twomore » distinct binding modes. Using surface plasmon resonance, we also examined the binding of UvsY to both ssDNA and the ssDNA–gp32 complex. These analyses confirmed that ssDNA can bind UvsY and gp32 independently and also as a ternary complex. They also showed that residues located on the rim of the heptamer are required for optimal binding to ssDNA, thus identifying the putative ssDNA-binding surface. We propose a model in which UvsY promotes a helical ssDNA conformation that disfavors the binding of gp32 and initiates the assembly of the ssDNA–UvsX filament.« less
2014-01-01
Background The trimeric envelope glycoproteins (Env) on the surface of HIV-1 virions are the targets for neutralizing antibodies (NAbs). No candidate HIV-1 immunogen has yet induced potent, broadly active NAbs (bNAbs). Part of the explanation may be that previously tested Env proteins inadequately mimic the functional, native Env complex. Trimerization and the proteolytic processing of Env precursors into gp120 and gp41 profoundly alter antigenicity, but soluble cleaved trimers are too unstable to serve as immunogens. By introducing stabilizing mutations (SOSIP), we constructed soluble, cleaved Env trimers derived from the HIV-1 subtype A isolate BG505 that resemble native Env spikes on virions both structurally and antigenically. Results We used surface plasmon resonance (SPR) to quantify antibody binding to different forms of BG505 Env: the proteolytically cleaved SOSIP.664 trimers, cleaved gp120-gp41ECTO protomers, and gp120 monomers. Non-NAbs to the CD4-binding site bound only marginally to the trimers but equally well to gp120-gp41ECTO protomers and gp120 monomers, whereas the bNAb VRC01, directed to the CD4bs, bound to all three forms. In contrast, bNAbs to V1V2 glycan-dependent epitopes bound preferentially (PG9 and PG16) or exclusively (PGT145) to trimers. We also explored the antigenic consequences of three different features of SOSIP.664 gp140 trimers: the engineered inter-subunit disulfide bond, the trimer-stabilizing I559P change in gp41ECTO, and proteolytic cleavage at the gp120-gp41ECTO junction. Each of these three features incrementally promoted native-like trimer antigenicity. We compared Fab and IgG versions of bNAbs and validated a bivalent model of IgG binding. The NAbs showed widely divergent binding kinetics and degrees of binding to native-like BG505 SOSIP.664. High off-rate constants and low stoichiometric estimates of NAb binding were associated with large amounts of residual infectivity after NAb neutralization of the corresponding BG505.T332N pseudovirus. Conclusions The antigenicity and structural integrity of cleaved BG505 SOSIP.664 trimers render these proteins good mimics of functional Env spikes on virions. In contrast, uncleaved gp140s antigenically resemble individual gp120-gp41ECTO protomers and gp120 monomers, but not native trimers. Although NAb binding to functional trimers may thus be both necessary and sufficient for neutralization, the kinetics and stoichiometry of the interaction influence the neutralizing efficacy of individual NAbs. PMID:24884783
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lundquist, K A
Mesoscale models, such as the Weather Research and Forecasting (WRF) model, are increasingly used for high resolution simulations, particularly in complex terrain, but errors associated with terrain-following coordinates degrade the accuracy of the solution. Use of an alternative Cartesian gridding technique, known as an immersed boundary method (IBM), alleviates coordinate transformation errors and eliminates restrictions on terrain slope which currently limit mesoscale models to slowly varying terrain. In this dissertation, an immersed boundary method is developed for use in numerical weather prediction. Use of the method facilitates explicit resolution of complex terrain, even urban terrain, in the WRF mesoscale model.more » First, the errors that arise in the WRF model when complex terrain is present are presented. This is accomplished using a scalar advection test case, and comparing the numerical solution to the analytical solution. Results are presented for different orders of advection schemes, grid resolutions and aspect ratios, as well as various degrees of terrain slope. For comparison, results from the same simulation are presented using the IBM. Both two-dimensional and three-dimensional immersed boundary methods are then described, along with details that are specific to the implementation of IBM in the WRF code. Our IBM is capable of imposing both Dirichlet and Neumann boundary conditions. Additionally, a method for coupling atmospheric physics parameterizations at the immersed boundary is presented, making IB methods much more functional in the context of numerical weather prediction models. The two-dimensional IB method is verified through comparisons of solutions for gentle terrain slopes when using IBM and terrain-following grids. The canonical case of flow over a Witch of Agnesi hill provides validation of the basic no-slip and zero gradient boundary conditions. Specified diurnal heating in a valley, producing anabatic winds, is used to validate the use of flux (non-zero) boundary conditions. This anabatic flow set-up is further coupled to atmospheric physics parameterizations, which calculate surface fluxes, demonstrating that the IBM can be coupled to various land-surface parameterizations in atmospheric models. Additionally, the IB method is extended to three dimensions, using both trilinear and inverse distance weighted interpolations. Results are presented for geostrophic flow over a three-dimensional hill. It is found that while the IB method using trilinear interpolation works well for simple three-dimensional geometries, a more flexible and robust method is needed for extremely complex geometries, as found in three-dimensional urban environments. A second, more flexible, immersed boundary method is devised using inverse distance weighting, and results are compared to the first IBM approach. Additionally, the functionality to nest a domain with resolved complex geometry inside of a parent domain without resolved complex geometry is described. The new IBM approach is used to model urban terrain from Oklahoma City in a one-way nested configuration, where lateral boundary conditions are provided by the parent domain. Finally, the IB method is extended to include wall model parameterizations for rough surfaces. Two possible implementations are presented, one which uses the log law to reconstruct velocities exterior to the solid domain, and one which reconstructs shear stress at the immersed boundary, rather than velocity. These methods are tested on the three-dimensional canonical case of neutral atmospheric boundary layer flow over flat terrain.« less
Inhibitors of the entry of HIV into host cells.
Meanwell, Nicholas A; Kadow, John F
2003-07-01
The development of mechanistic insight into the process by which HIV enters host cells has revealed a panoply of targets that offer considerable potential as sites for pharmacological intervention. The gp120/gp41 protein complex, expressed on the virion surface, mediates HIV entry by a process initiated by the engagement of the host cell receptor CD4. Subtle conformational changes triggered by this interaction expose elements of gp120 to the seven-transmembrane, G protein-coupled chemokine receptors CCR5 or CXCR4 expressed on host cells, a contact that relieves constraints imposed on gp41 by gp120. This leads to a major conformational rearrangement of gp41, which results in the insertion of the fusion peptide into the host cell membrane and the assembly of the amino terminus heptad repeat into a trimeric form that is subsequently recognized by the carboxy terminal heptad repeat. The latter process leads to juxtaposition of the viral and host cell membranes, a prelude to fusion. The most prominent strategies and targets that are actively being exploited as drug discovery opportunities are inhibition of the attachment of HIV to host cells, blockade of chemokine receptors and interference with the function of gp41. Inhibitors of each of these steps in the HIV entry process with potential clinical relevance are reviewed in the context of their status in the drug development process. The most significant entity to emerge from this area of research to date is enfuvirtide, a 36-amino acid derivative that interferes with the function of gp41. Enfuvirtide is the first HIV entry inhibitor to be granted a license for marketing (it was approved in the US and Europe in March 2003), and its introduction portends the beginning of what promises to be an exciting new era of HIV therapy.
2015-01-01
Envelope protein gp120 of human immunodeficiency virus (HIV) is armored with a dense glycan shield, which plays critical roles in envelope folding, immune-evasion, infectivity, and immunogenicity. Site-specific glycosylation profiling of recombinant gp120 is very challenging. Therefore, glycoproteomic analysis of native viral gp120 is still formidable to date. This challenge promoted us to employ a Q-Exactive mass spectrometer to identify low abundant glycopeptides from virion-associated gp120. To search the HCD-MS data for glycopeptides, a novel spectral-aligning strategy was developed. This strategy depends on the observation that glycopeptides and the corresponding deglycosylated peptides share very similar MS/MS pattern in terms of b- and y-ions that do not contain the site of glycosylation. Moreover, glycopeptides with an identical peptide backbone show nearly resembling spectra regardless of the attached glycan structures. For the recombinant gp120, this “copy–paste” spectral pattern of glycopeptides facilitated identification of 2224 spectra using only 18 spectral templates, and after precursor mass correction, 1268 (57%) spectra were assigned to 460 unique glycopeptides accommodating 19 N-linked and one O-linked glycosylation sites (glycosites). Strikingly, we were able to observe five N- and one O-linked glycosites in native gp120. We further revealed that except for Asn276 in the C2 region, glycans were processed to contain both high mannose and hybrid/complex glycans; an additional four N-linked glycosites were decorated with high mannose type. Core 1 O-linked glycan Gal1GalNAc1 was seen for the O-linked glycosite at Thr499. This direct observation of site-specific glycosylation of virion-derived gp120 has implications in HIV glycobiology and vaccine design. PMID:24941220
Response Surface Analysis of Stochastic Network Performance
1988-12-01
Bl5/32768/, B16 /65536/,P/2147483647/ XHI-IX/B 16 XALO=(IX-XHI* Bl6 )*A LEFTLO=XALO/ Bl6 FHI=XHI*A+LEFTLO IC=FHI/B1 5 IX-(((XALO-LEFTLO* Bl6 )-P)4(FHI-K*Bl5...ELSE GO TO 50 END IF GO TO 50 100 END D-5 * RANDOM NUMBER GENERATOR FUNCTION RANDOM( IX) INTEGER AP, IX,B15, B16 ,XHI ,XALOI,LEFTLO,FHI ,K DATA A/16807... Bl6 )+K IF(IX.LT.O) IX=IX+P RANDOM-FLOAT( IX) *4.656612875E-1O RETURN END * NETWORK ENTRY and * PATHSET AND CUTSET GENERATION SUBROUTINE SUBROUTINE
McVoy, Michael A; Wang, Jian Ben; Dittmer, Dirk P; Bierle, Craig J; Swanson, Elizabeth C; Fernández-Alarcón, Claudia; Hernandez-Alvarado, Nelmary; Zabeli, Jason C; Schleiss, Mark R
2016-09-01
Guinea pig cytomegalovirus (GPCMV) provides a valuable model for congenital cytomegalovirus transmission. Salivary gland (SG)-passaged stocks of GPCMV are pathogenic, while tissue culture (TC) passage in fibroblasts results in attenuation. Nonpathogenic TC-derived virus N13R10 (cloned as a bacterial artificial chromosome [BAC]) has a 4-bp deletion that disrupts GP129, which encodes a subunit of the GPCMV pentameric complex (PC) believed to govern viral entry into select cell types, and GP130, an overlapping open reading frame (ORF) of unknown function. To determine if this deletion contributes to attenuation of N13R10, markerless gene transfer in Escherichia coli was used to construct virus r129, a variant of N13R10 in which the 4-bp deletion is repaired. Virions from r129 were found to contain GP129 as well as two other PC subunit proteins, GP131 and GP133, whereas these three PC subunits were absent from N13R10 virions. Replication of r129 in fibroblasts appeared unaltered compared to that of N13R10. However, following experimental challenge of immunocompromised guinea pigs, r129 induced significant weight loss, longer duration of viremia, and dramatically higher (up to 1.5 × 10(6)-fold) viral loads in blood and end organs compared to N13R10. In pregnant guinea pigs, challenge with doses of r129 virus of ≥5 × 10(6) PFU resulted in levels of maternal viremia, congenital transmission, pup viral loads, intrauterine growth restriction, and pup mortality comparable to that induced by pathogenic SG virus, although higher doses of r129 were required. These results suggest that the GP129-GP130 mutation is a significant contributor to attenuation of N13R10, likely by abrogating expression of a functional PC. Tissue culture adaptation of cytomegaloviruses rapidly selects for mutations, deletions, and rearrangements in the genome, particularly for viruses passaged in fibroblast cells. Some of these mutations are focused in the region of the genome encoding components of the pentameric complex (PC), in particular homologs of human cytomegalovirus (HCMV) proteins UL128, UL130, and UL131A. These mutations can attenuate the course of infection when the virus is reintroduced into animals for vaccine and pathogenesis studies. This study demonstrates that a deletion that arose during the process of tissue culture passage can be repaired, with subsequent restoration of pathogenicity, using BAC-based mutagenesis. Restoration of pathogenicity by repair of a frameshift mutation in GPCMV gene GP129 using this approach provides a valuable genetic platform for future studies using the guinea pig model of congenital CMV infection. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
Xu, Yuqun; Miyakawa, Takuya; Nakamura, Hidemitsu; Nakamura, Akira; Imamura, Yusaku; Asami, Tadao; Tanokura, Masaru
2016-01-01
The perception of two plant germination inducers, karrikins and strigolactones, are mediated by the proteins KAI2 and D14. Recently, KAI2-type proteins from parasitic weeds, which are possibly related to seed germination induced by strigolactone, have been classified into three clades characterized by different responses to karrikin/strigolactone. Here we characterized a karrikin-binding protein in Striga (ShKAI2iB) that belongs to intermediate-evolving KAI2 and provided the structural bases for its karrikin-binding specificity. Binding assays showed that ShKAI2iB bound karrikins but not strigolactone, differing from other KAI2 and D14. The crystal structures of ShKAI2iB and ShKAI2iB-karrikin complex revealed obvious structural differences in a helix located at the entry of its ligand-binding cavity. This results in a smaller closed pocket, which is also the major cause of ShKAI2iB’s specificity of binding karrikin. Our structural study also revealed that a few non-conserved amino acids led to the distinct ligand-binding profile of ShKAI2iB, suggesting that the evolution of KAI2 resulted in its diverse functions. PMID:27507097
Pusceddu, M M; Murray, K; Gareau, M G
2018-03-01
The crosstalk between the gut and the brain has revealed a complex communication system responsible for maintaining a proper gastrointestinal homeostasis as well as affect emotional mood and cognitive functions. Recent research has revealed that beneficial manipulation of the microbiota by probiotics and prebiotics represent an emerging and novel strategy for the treatment of a large spectrum of diseases ranging from visceral pain to mood disorders. The review critically evaluates current knowledge of the effects exerted by both probiotics and prebiotics in irritable bowel syndrome (IBS) and mood disorders such as anxiety and depression. Relevant literature was identified through a search of MEDLINE via PubMed using the following words, "probiotics", "prebiotics", "microbiota", and "gut-brain axis" in combination with "stress", "depression", "IBS", and "anxiety". A number of trials have shown efficacy of probiotics and prebiotics in ameliorating both IBS related symptoms and emotional states. However, limitations have been found especially due to the small number of clinical studies, studies design, patient sample size, and placebo effect. Nonetheless, current finding supports the view that beneficial manipulation of the microbiota through both probiotics and prebiotics intake represents a novel attractive strategy to treat gut-brain axis disorders such as IBS and depression.
Advancements in drug development for diarrhea-predominant irritable bowel syndrome.
Dothel, Giovanni; Barbaro, Maria Raffaella; Raschi, Emanuel; Barbara, Giovanni; De Ponti, Fabrizio
2018-03-01
Diarrhea-predominant irritable bowel syndrome (IBS-D) is a common disorder characterized by a complex pathophysiology hampering optimal targeted drug development. Recent advances in our understanding of key underlying mechanisms prompted novel therapeutics including novel pharmacological approaches. Areas covered: This review summarizes the latest advancements in the pipeline of IBS-D drugs focusing on new pharmacological targets, efficacy and safety of medicinal products considering the recent harmonization of regulatory requirements by the FDA and the EMA. Expert opinion: The new 5-HT 3 receptor antagonist ramosetron appears a promising therapeutic approach devoid of significant adverse events, although it is presently unavailable in Western countries, most likely because of the precautionary approach taken by regulatory agencies with this drug class. New pharmacological concepts on full agonists/antagonists, mixed-receptor activity and novel drug targets may streamline the present drug pipeline along with the adherence on new regulatory guidelines on outcome measures. Eluxadoline can be taken as an example of this paradigm shift. It has now been granted marketing authorization for IBS-D on both sides of the Atlantic, but it is still considered as a second-line agent by the NICE. There is still much work to be done to fully cover clinical needs of patients with IBS-D.
Long, Yi; Du, Zhi-Jiang; Chen, Chao-Feng; Dong, Wei; Wang, Wei-Dong
2017-07-01
The most important step for lower extremity exoskeleton is to infer human motion intent (HMI), which contributes to achieve human exoskeleton collaboration. Since the user is in the control loop, the relationship between human robot interaction (HRI) information and HMI is nonlinear and complicated, which is difficult to be modeled by using mathematical approaches. The nonlinear approximation can be learned by using machine learning approaches. Gaussian Process (GP) regression is suitable for high-dimensional and small-sample nonlinear regression problems. GP regression is restrictive for large data sets due to its computation complexity. In this paper, an online sparse GP algorithm is constructed to learn the HMI. The original training dataset is collected when the user wears the exoskeleton system with friction compensation to perform unconstrained movement as far as possible. The dataset has two kinds of data, i.e., (1) physical HRI, which is collected by torque sensors placed at the interaction cuffs for the active joints, i.e., knee joints; (2) joint angular position, which is measured by optical position sensors. To reduce the computation complexity of GP, grey relational analysis (GRA) is utilized to specify the original dataset and provide the final training dataset. Those hyper-parameters are optimized offline by maximizing marginal likelihood and will be applied into online GP regression algorithm. The HMI, i.e., angular position of human joints, will be regarded as the reference trajectory for the mechanical legs. To verify the effectiveness of the proposed algorithm, experiments are performed on a subject at a natural speed. The experimental results show the HMI can be obtained in real time, which can be extended and employed in the similar exoskeleton systems.
A transcriptomic approach to search for novel phenotypic regulators in McArdle disease.
Nogales-Gadea, Gisela; Consuegra-García, Inés; Rubio, Juan C; Arenas, Joaquin; Cuadros, Marc; Camara, Yolanda; Torres-Torronteras, Javier; Fiuza-Luces, Carmen; Lucia, Alejandro; Martín, Miguel A; García-Arumí, Elena; Andreu, Antoni L
2012-01-01
McArdle disease is caused by lack of glycogen phosphorylase (GP) activity in skeletal muscle. Patients experience exercise intolerance, presenting as early fatigue and contractures. In this study, we investigated the effects produced by a lack of GP on several genes and proteins of skeletal muscle in McArdle patients. Muscle tissue of 35 patients and 7 healthy controls were used to identify abnormalities in the patients' transcriptomic profile using low-density arrays. Gene expression was analyzed for the influence of variables such as sex and clinical severity. Differences in protein expression were studied by immunoblotting and 2D electrophoresis analysis, and protein complexes were examined by two-dimensional, blue native gel electrophoresis (BN-PAGE). A number of genes including those encoding acetyl-coA carboxylase beta, m-cadherin, calpain III, creatine kinase, glycogen synthase (GS), and sarcoplasmic reticulum calcium ATPase 1 (SERCA1), were found to be downregulated in patients. Specifically, compared to controls, GS and SERCA1 proteins were reduced by 50% and 75% respectively; also, unphosphorylated GS and SERCA1 were highly downregulated. On BN-PAGE analysis, GP was present with GS in two muscle protein complexes. Our findings revealed some issues that could be important in understanding the physiological consequences of McArdle disease: (i) SERCA1 downregulation in patients could result in impaired calcium transport in type II (fast-twitch) muscle fibers, leading to early fatigability during exercise tasks involving type II fibers (which mostly use glycolytic metabolism), i.e. isometric exercise, lifting weights or intense dynamic exercise (stair climbing, bicycling, walking at a very brisk pace), (ii) GP and GS were found together in two protein complexes, which suggests a new regulatory mechanism in the activity of these glycogen enzymes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kind, Barbara, E-mail: barbara.kind@uniklinikum-dresden.de; Koehler, Katrin, E-mail: katrin.koehler@uniklinikum-dresden.de; Lorenz, Mike, E-mail: mlorenz@mpi-cbg.de
2009-12-11
The nuclear pore complex (NPC) consists of {approx}30 different proteins and provides the only sites for macromolecular transport between cytoplasm and nucleus. ALADIN was discovered as a new member of the NPC. Mutations in ALADIN are known to cause triple A syndrome, a rare autosomal recessive disorder characterized by adrenal insufficiency, alacrima, and achalasia. The function and exact location of the nucleoporin ALADIN within the NPC multiprotein complex is still unclear. Using a siRNA-based approach we downregulated the three known membrane integrated nucleoporins NDC1, GP210, and POM121 in stably expressing GFP-ALADIN HeLa cells. We identified NDC1 but not GP210 andmore » POM121 as the main anchor of ALADIN within the NPC. Solely the depletion of NDC1 caused mislocalization of ALADIN. Vice versa, the depletion of ALADIN led also to disappearance of NDC1 at the NPC. However, the downregulation of two further membrane-integral nucleoporins GP210 and POM121 had no effect on ALADIN localization. Furthermore, we could show a direct association of NDC1 and ALADIN in NPCs by fluorescence resonance energy transfer (FRET) measurements. Based on our findings we conclude that ALADIN is anchored in the nuclear envelope via NDC1 and that this interaction gets lost, if ALADIN is mutated. The loss of integration of ALADIN in the NPC is a main pathogenetic aspect for the development of the triple A syndrome and suggests that the interaction between ALADIN and NDC1 may be involved in the pathogenesis of the disease.« less
Reconnaissance In Megacities: Lessons From The Past
2016-05-26
Operations: Visualizing the Elephant (Santa Monica: RAND, 2004), ix. 49 prevented a coordinated and decisive response. In Fallujah and Sadr City, air and...Monica: RAND, 2000. ———. Managing Complexity During Military Operations: Visualizing the Elephant . Santa Monica: RAND, 2004. Glenn, Russell W
Wilcz-Villega, E; McClean, S; O'Sullivan, M
2014-03-01
Increased intestinal permeability and altered expression of tight junction (TJ) proteins may be implicated in the pathogenesis of irritable bowel syndrome (IBS). This study aimed to investigate the expression of adherens junction (AJ) protein E-cadherin and TJ proteins zonula occludens (ZO)-1 and claudin (CLD)-1 and associations with IBS symptoms. Junctional proteins were immunostained in cecal biopsy tissue of Rome II IBS patients (n = 34) comprising both alternating (IBS-A) and diarrhea predominant (IBS-D) subtypes, and controls (n = 12). IBS symptom duration, abdominal pain severity and stool frequency were assessed for IBS patients. Protein expression was determined by immunofluorescence. E-cadherin and ZO-1 protein expression was significantly lower (p = 0.03 and p = 0.016, respectively) in the cecal surface epithelium of the IBS group comprising both IBS-A and IBS-D subtypes. CLD-1 expression was not significantly altered compared with controls. On subtype analysis, ZO-1 expression was significantly reduced in both IBS-A and IBS-D compared with controls, whereas E-cadherin was reduced only in IBS-A. Lower E-cadherin expression was associated with longer symptoms duration specifically in IBS-A patients (rs = -0.76, p = 0.004). Reduced E-cadherin associated with abdominal pain severity in the overall IBS group (rs = -0.36, p = 0.041), but this association was unrelated to IBS subtype. E-cadherin protein expression in the cecum was significantly lower in IBS-A compared with controls and associated with longstanding symptoms. E-cadherin was further associated with abdominal pain severity in the IBS group overall, but unrelated to IBS subtype. Altered E-cadherin expression may provide novel insights into mechanisms underlying intestinal barrier dysfunction in IBS. © 2013 John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Gibbs, Summer L.; O'Hara, Julia A.; Hoopes, P. Jack; Pogue, Brian W.
2007-02-01
The Aminolevulinic Acid (ALA) - Protoporphyrin IX (PpIX) system is unique in the world of photosensitizers in that the prodrug ALA is enzymatically transformed via the tissue of interest into fluorescently detectable levels of PpIX. This system can be used to monitor cellular metabolism of tumor tissue for applications such as therapy monitoring. Detecting PpIX fluorescence noninvasively has proven difficult due to the high levels of PpIX produced in the skin compared to other tissue both with and without ALA administration. In the current study, methods to decrease skin PpIX autofluorescence and skin PpIX fluorescence following ALA administration have been examined. Use of a purified diet is found to decrease both skin PpIX autofluorescence and skin PpIX fluorescence following ALA administration, while addition of a broad spectrum antibiotic to the water shows little effect. Following ALA administration, improved brain tumor detection is seen when skin PpIX fluorescence is photobleached via blue light prior to transmission spectroscopic measurements of tumor bearing and control animals. Both of these methods to decrease skin PpIX autofluorescence and skin PpIX fluorescence following ALA administration are shown to have a large effect on the ability to detect tumor tissue PpIX fluorescence noninvasively in vivo.
Identification of a D-amino acid decapeptide HIV-1 entry inhibitor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Boggiano, Cesar; Jiang Shibo; Lu Hong
2006-09-08
Entry of human immunodeficiency virus type 1 (HIV-1) virion into host cells involves three major steps, each being a potential target for the development of entry inhibitors: gp120 binding to CD4, gp120-CD4 complex interacting with a coreceptor, and gp41 refolding to form a six-helix bundle. Using a D-amino acid decapeptide combinatorial library, we identified peptide DC13 as having potent HIV-1 fusion inhibitory activity, and effectively inhibiting infection by several laboratory-adapted and primary HIV-1 strains. While DC13 did not block binding of gp120 to CD4, nor disrupt the gp41 six-helix bundle formation, it effectively blocked the binding of an anti-CXCR4 monoclonalmore » antibody and chemokine SDF-1{alpha} to CXCR4-expressing cells. However, because R5-using primary viruses were also neutralized, the antiviral activity of DC13 implies additional mode(s) of action. These results suggest that DC13 is a useful HIV-1 coreceptor antagonist for CXCR4 and, due to its biostability and simplicity, may be of value for developing a new class of HIV-1 entry inhibitors.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huang, Chih-chin; Stricher, Francois; Martin, Loic
The binding surface on CD4 for the HIV-1 gp120 envelope glycoprotein has been transplanted previously onto a scorpion-toxin scaffold. Here, we use X-ray crystallography to characterize atomic-level details of gp120 with this transplant, CD4M33. Despite known envelope flexibility, the conformation of gp120 induced by CD4M33 was so similar to that induced by CD4 that localized measures were required to distinguish ligand-induced differences from lattice variation. To investigate relationships between structure, function, and mimicry, an F23 analog of CD4M33 was devised. Structural and thermodynamic analyses showed F23 to be a better molecular mimic of CD4 than CD4M33. F23 also showed increasedmore » neutralization breadth, against diverse isolates of HIV-1, HIV-2, and SIVcpz. Our results lend insight into the stability of the CD4 bound conformation of gp120, define measures that quantify molecular mimicry as a function of evolutionary distance, and suggest how such evaluations might be useful in developing mimetic antagonists with increased neutralization breadth.« less
Heix, Jutta; Zomerdijk, Joost C. B. M.; Ravanpay, Ali; Tjian, Robert; Grummt, Ingrid
1997-01-01
Promoter selectivity for all three classes of eukaryotic RNA polymerases is brought about by multimeric protein complexes containing TATA box binding protein (TBP) and specific TBP-associated factors (TAFs). Unlike class II- and III-specific TBP–TAF complexes, the corresponding murine and human class I-specific transcription initiation factor TIF-IB/SL1 exhibits a pronounced selectivity for its homologous promoter. As a first step toward understanding the molecular basis of species-specific promoter recognition, we cloned the cDNAs encoding the three mouse pol I-specific TBP-associated factors (TAFIs) and compared the amino acid sequences of the murine TAFIs with their human counterparts. The four subunits from either species can form stable chimeric complexes that contain stoichiometric amounts of TBP and TAFIs, demonstrating that differences in the primary structure of human and mouse TAFIs do not dramatically alter the network of protein–protein contacts responsible for assembly of the multimeric complex. Thus, primate vs. rodent promoter selectivity mediated by the TBP–TAFI complex is likely to be the result of cumulative subtle differences between individual subunits that lead to species-specific properties of RNA polymerase I transcription. PMID:9050847
Structural Basis for Marburg Virus Neutralization by a Cross-Reactive Human Antibody
Hashiguchi, Takao; Fusco, Marnie L.; Bornholdt, Zachary A.; ...
2015-02-26
The filoviruses, including Marburg and Ebola, express a single glycoprotein on their surface, termed GP, which is responsible for attachment and entry of target cells. Filovirus GPs differ by up to 70% in protein sequence, and no antibodies are yet described that cross-react among them. Here, we present the 3.6 Å crystal structure of Marburg virus GP in complex with a cross-reactive antibody from a human survivor, and a lower resolution structure of the antibody bound to Ebola virus GP. The antibody, MR78, recognizes a GP1 epitope conserved across the filovirus family, which likely represents the binding site of theirmore » NPC1 receptor. Indeed, MR78 blocks binding of the essential NPC1 domain C. We find that these structures and additional small-angle X-ray scattering of mucin-containing MARV and EBOV GPs suggest why such antibodies were not previously elicited in studies of Ebola virus, and provide critical templates for development of immunotherapeutics and inhibitors of entry.« less
Structural basis for Marburg virus neutralization by a cross-reactive human antibody.
Hashiguchi, Takao; Fusco, Marnie L; Bornholdt, Zachary A; Lee, Jeffrey E; Flyak, Andrew I; Matsuoka, Rei; Kohda, Daisuke; Yanagi, Yusuke; Hammel, Michal; Crowe, James E; Saphire, Erica Ollmann
2015-02-26
The filoviruses, including Marburg and Ebola, express a single glycoprotein on their surface, termed GP, which is responsible for attachment and entry of target cells. Filovirus GPs differ by up to 70% in protein sequence, and no antibodies are yet described that cross-react among them. Here, we present the 3.6 Å crystal structure of Marburg virus GP in complex with a cross-reactive antibody from a human survivor, and a lower resolution structure of the antibody bound to Ebola virus GP. The antibody, MR78, recognizes a GP1 epitope conserved across the filovirus family, which likely represents the binding site of their NPC1 receptor. Indeed, MR78 blocks binding of the essential NPC1 domain C. These structures and additional small-angle X-ray scattering of mucin-containing MARV and EBOV GPs suggest why such antibodies were not previously elicited in studies of Ebola virus, and provide critical templates for development of immunotherapeutics and inhibitors of entry. Copyright © 2015 Elsevier Inc. All rights reserved.
Uterine Deletion of Gp130 or Stat3 Shows Implantation Failure with Increased Estrogenic Responses
Sun, Xiaofei; Bartos, Amanda; Whitsett, Jeffrey A.
2013-01-01
Leukemia inhibitory factor (LIF), a downstream target of estrogen, is essential for implantation in mice. LIF function is thought to be mediated by its binding to LIF receptor (LIFR) and recruitment of coreceptor GP130 (glycoprotein 130), and this receptor complex then activates signal transducer and activator of transcription (STAT)1/3. However, the importance of LIFR and GP130 acting via STAT3 in implantation remains uncertain, because constitutive inactivation of Lifr, Gp130, or Stat3 shows embryonic lethality in mice. To address this issue, we generated mice with conditional deletion of uterine Gp130 or Stat3 and show that both GP130 and STAT3 are critical for uterine receptivity and implantation. Implantation failure in these deleted mice is associated with higher uterine estrogenic responses prior to the time of implantation. These heightened estrogenic responses are not due to changes in ovarian hormone levels or expression of their nuclear receptors. In the deleted mice, estrogen-responsive gene, Lactoferrin (Ltf), and Mucin 1 protein, were up-regulated in the uterus. In addition, progesterone-responsive genes, Hoxa10 and Indian hedgehog (Ihh), were markedly down-regulated in STAT3-inactivated uteri. These changes in uteri of deleted mice were reflected by the failure of differentiation of the luminal epithelium, which is essential for blastocyst attachment. PMID:23885093
DOE Office of Scientific and Technical Information (OSTI.GOV)
Getman, Konstantin V.; Feigelson, Eric D.; Kuhn, Michael A.
2014-06-01
A major impediment to understanding star formation in massive star-forming regions (MSFRs) is the absence of a reliable stellar chronometer to unravel their complex star formation histories. We present a new estimation of stellar ages using a new method that employs near-infrared (NIR) and X-ray photometry, Age {sub JX} . Stellar masses are derived from X-ray luminosities using the L{sub X} -M relation from the Taurus cloud. J-band luminosities are compared to mass-dependent pre-main-sequence (PMS) evolutionary models to estimate ages. Age {sub JX} is sensitive to a wide range of evolutionary stages, from disk-bearing stars embedded in a cloud tomore » widely dispersed older PMS stars. The Massive Young Star-Forming Complex Study in Infrared and X-ray (MYStIX) project characterizes 20 OB-dominated MSFRs using X-ray, mid-infrared, and NIR catalogs. The Age {sub JX} method has been applied to 5525 out of 31,784 MYStIX Probable Complex Members. We provide a homogeneous set of median ages for over 100 subclusters in 15 MSFRs; median subcluster ages range between 0.5 Myr and 5 Myr. The important science result is the discovery of age gradients across MYStIX regions. The wide MSFR age distribution appears as spatially segregated structures with different ages. The Age {sub JX} ages are youngest in obscured locations in molecular clouds, intermediate in revealed stellar clusters, and oldest in distributed populations. The NIR color index J – H, a surrogate measure of extinction, can serve as an approximate age predictor for young embedded clusters.« less
NASA Astrophysics Data System (ADS)
Anand, Sanjay; Hasan, Tayyaba; Maytin, Edward V.
2013-03-01
Photodynamic therapy (PDT) with aminolevulinate (ALA) is widely accepted as an effective treatment for superficial carcinomas and pre-cancers. However, PDT is still suboptimal for deeper tumors, mainly due to inadequate ALA penetration and subsequent conversion to PpIX. We are interested in improving the effectiveness of photodynamic therapy (PDT) for deep tumors, using a combination approach (cPDT) in which target protoporphyrin (PpIX) levels are significantly enhanced by differentiation caused by giving Vitamin D or methotrexate (MTX) for 3 days prior to ALAPDT. In LNCaP and MEL cells, a strong correlation between inducible differentiation and expression of C/EBP transcription factors, as well as between differentiation and mRNA levels of CPO (a key heme-synthetic enzyme), indicates the possibility of CPO transcriptional regulation by the C/EBPs. Sequence analysis of the first 1300 base pairs of the murine CPO upstream region revealed 15 consensus C/EBP binding sites. Electrophoretic Mobility Shift Assays (EMSA) proved that these sites form specific complexes that have strong, moderate or weak affinities for C/EBPs. However, in the context of the full-length CPO promoter, inactivation of any type of site (strong or weak) reduced CPO promoter activity (luciferase assay) to nearly the same extent, suggesting cooperative interactions. A comparative analysis of murine and human CPO promoters revealed possible protein-protein interactions between C/EBPs and several neighboring transcription factors such as NFkB, Sp1, AP-1, CBP/p300 and CREB (an enhanceosome complex). Overall, these results confirm that C/EBP's are important for CPO expression via complex mechanisms which upregulate PpIX and enhance the outcome of cPDT.
Sulaberidze, G; Okujava, M; Liluashvili, K; Tughushi, M; Abramashvili, M
2017-03-01
The causes of motility disorder of gastrointestinal tract and in particular Irritable Bowel Syndrome IBS are multifold, leading to complexity of treatment and requirement of more precise investigation of different pharmacological and non-pharmacological approaches. The aim of the study was investigation and comparison of the dietary fiber intake among women with constipation-predominant irritable bowel syndrome (IBS-C) and without, improvement of the dietary fiber intake using interventions with less rough changes of food related behavior and study of its effects on the bowel function, general wellbeing and compliance of patients. In total 100 healthy women, without any clinical signs of gastrointestinal disorders and 98 women who met Rome III criteria of IBS-C were enrolled in the dietary fiber intake assessment survey. The dietary habits of all participants, as well as bowel function, digestive feelings and general wellbeing of patients at baseline, on the 7th and 14th day of dietary intervention was assessed by the means of adopted questionnaires. The dietary supplementation was provided during the breakfast with fiber enriched food - bread and muesli. Research data reviled significantly lower daily intake of dietary fiber among patients with IBS-C compared with healthy group. The main source of dietary fiber in IBS-C group was bread and cereals, therefore introduction of dietary fiber rich bread and muesli in the breakfast didn't affect diet-related habits and determined high compliance of patients. Two week long intervention significantly improved the bowel function and irritation related complains, the feeling of general wellbeing was considerably better on the endpoint as well.
The Overlap between Irritable Bowel Syndrome and Non-Celiac Gluten Sensitivity: A Clinical Dilemma.
Makharia, Archita; Catassi, Carlo; Makharia, Govind K
2015-12-10
The spectrum of gluten-related disorders has widened in recent times and includes celiac disease, non-celiac gluten sensitivity, and wheat allergy. The complex of symptoms associated with these diseases, such as diarrhea, constipation or abdominal pain may overlap for the gluten related diseases, and furthermore they can be similar to those caused by various other intestinal diseases, such as irritable bowel syndrome (IBS). The mechanisms underlying symptom generation are diverse for all these diseases. Some patients with celiac disease may remain asymptomatic or have only mild gastrointestinal symptoms and thus may qualify for the diagnosis of IBS in the general clinical practice. Similarly, the overlap of symptoms between IBS and non-celiac gluten sensitivity (NCGS) often creates a dilemma for clinicians. While the treatment of NCGS is exclusion of gluten from the diet, some, but not all, of the patients with IBS also improve on a gluten-free diet. Both IBS and NCGS are common in the general population and both can coexist with each other independently without necessarily sharing a common pathophysiological basis. Although the pathogenesis of NCGS is not well understood, it is likely to be heterogeneous with possible contributing factors such as low-grade intestinal inflammation, increased intestinal barrier function and changes in the intestinal microbiota. Innate immunity may also play a pivotal role. One possible inducer of innate immune response has recently been reported to be amylase-trypsin inhibitor, a protein present in wheat endosperm and the source of flour, along with the gluten proteins.
The Overlap between Irritable Bowel Syndrome and Non-Celiac Gluten Sensitivity: A Clinical Dilemma
Makharia, Archita; Catassi, Carlo; Makharia, Govind K.
2015-01-01
The spectrum of gluten-related disorders has widened in recent times and includes celiac disease, non-celiac gluten sensitivity, and wheat allergy. The complex of symptoms associated with these diseases, such as diarrhea, constipation or abdominal pain may overlap for the gluten related diseases, and furthermore they can be similar to those caused by various other intestinal diseases, such as irritable bowel syndrome (IBS). The mechanisms underlying symptom generation are diverse for all these diseases. Some patients with celiac disease may remain asymptomatic or have only mild gastrointestinal symptoms and thus may qualify for the diagnosis of IBS in the general clinical practice. Similarly, the overlap of symptoms between IBS and non-celiac gluten sensitivity (NCGS) often creates a dilemma for clinicians. While the treatment of NCGS is exclusion of gluten from the diet, some, but not all, of the patients with IBS also improve on a gluten-free diet. Both IBS and NCGS are common in the general population and both can coexist with each other independently without necessarily sharing a common pathophysiological basis. Although the pathogenesis of NCGS is not well understood, it is likely to be heterogeneous with possible contributing factors such as low-grade intestinal inflammation, increased intestinal barrier function and changes in the intestinal microbiota. Innate immunity may also play a pivotal role. One possible inducer of innate immune response has recently been reported to be amylase-trypsin inhibitor, a protein present in wheat endosperm and the source of flour, along with the gluten proteins. PMID:26690475
Johnson, Nathan A; Vallejo, Roger L; Silverstein, Jeffrey T; Welch, Timothy J; Wiens, Gregory D; Hallerman, Eric M; Palti, Yniv
2008-01-01
Genes within the major histocompatibility complex (MHC) are important for both innate and adaptive immune responses in mammals; however, much less is known regarding their contribution in teleost fishes. We examined the involvement of four major histocompatibility (MH) genomic regions in rainbow trout in resistance to the causative agent of bacterial coldwater disease (BCWD), Flavobacterium psychrophilum. Fish from the 2005 NCCCWA brood-year (71 full-sib families) were challenged with F. psychrophilum strain CSF 259-93. The overall mortality rate was 70%, with large variation in mortality between families. Disease resistance was quantified as post-challenge days to death. Phenotypic variation and additive genetic variation were estimated using mixed models of survival analysis. To examine association, eight microsatellite markers were isolated from MH gene-containing BAC clones and mapped onto the rainbow trout genetic linkage map. The parents and grandparents of the 2005 brood-year families were genotyped with these eight markers and another two markers tightly linked to the MH-IB region to assess the extent of linkage disequilibrium (LD) of MH genomic regions MH-IA, MH-IB, TAP1, and MH-II with survival post-challenge. MH-IB and MH-II markers were linked to BCWD survivability when data were analyzed by family. Tests for disease association at the population level substantiated the involvement of MH-IB, but not MH-II, with disease resistance. The impact of selective breeding for disease resistance on MH sequence variation is discussed in the context of aquaculture production.
Charbonneau, Duane; Gibb, Roger D.; Quigley, Eamonn M.M.
2013-01-01
Certain randomized, placebo-controlled trials of oral supplementation with B. infantis 35624 have demonstrated the amelioration of symptoms of irritable bowel syndrome. Potential GI colonization by B. infantis 35624 or effects of supplementation on resident GI microbiota may pertain to these clinical observations. In this study, fecal excretion of B. infantis 35624 before, during and after 8 weeks of daily treatment was compared in subjects with IBS who received either the encapsulated oral supplement (n = 39) or placebo (n = 37) and in healthy subjects who received the supplement (n = 41). Secondarily, changes in assessed fecal microbiota and IBS symptoms were determined. Supplementation significantly increased fecal B. infantis 35624 excretion vs. placebo in IBS subjects; excretion in healthy subjects receiving supplement was quantitatively similar. Fecal levels of the probiotic declined and approached baseline once dosing ceased, documenting that colonization is transient. Although supplementation increased numbers of B infantis 35624 within the GI tract, limited changes in 10 other fecal taxa were observed either in healthy subjects or those with IBS. No impact on IBS symptoms was observed. Detection of bacterial DNA in fecal samples suggests that the probiotic is able to survive transit through the GI tract, although strain selective culture techniques were not performed to confirm viability of B. infantis 35624 in the feces. Continuous probiotic administration was necessary to maintain steady-state transit. Given the complex spectrum of GI microbiota, however, monitoring perturbations in selected taxa may not be not a useful indicator of probiotic function. PMID:23549409
Ali, Ather; Weiss, Theresa R; McKee, Douglas; Scherban, Alisa; Khan, Sumiya; Fields, Maxine R; Apollo, Damian; Mehal, Wajahat Z
2017-01-01
Background Patients with irritable bowel syndrome (IBS) are often placed on diets guided by food intolerance assays, although these have not been validated. We assessed the effects of individualised diets in patients with IBS guided by a leucocyte activation test. Methods This is a parallel-group, double-blind, randomised controlled trial of 58 adults with IBS seen at an academic health centre in Northeast USA. Peripheral venous blood was analysed using a leucocyte activation test; individual foods were reported to produce positive or negative results. Participants were randomised to a 4-week diet with either individualised guidance to eliminate foods with positive assay results and allow foods with negative assay results (intervention), or with individualised guidance, matched in rigour and complexity, to eliminate foods with negative assay results and allow foods with positive assay results (comparison). The primary outcome was between-group differences in the IBS Global Improvement Scale (GIS). Secondary outcomes included reductions in IBS Symptom Severity Scale (SSS) scores and increases in IBS Adequate Relief (AR) and Quality of Life (QOL) scores. An aptamer-based proteomic analysis was conducted in strong responders. Results The intervention group had significantly greater increases in mean GIS score after 4 weeks (0.86 vs comparison; 95% CI 0.05 to 1.67; p=0.04) and 8 weeks (1.22 vs comparison; 95% CI 0.22 to 2.22; p=0.02). The intervention group also had significantly greater reductions in mean SSS score at 4 weeks (–61.78 vs comparison; 95% CI –4.43 to –119.14; p=0.04) and 8 weeks (–66.42 vs comparison; 95% CI –5.75 to –127.09; p=0.03). There were no significant differences between intervention and comparison groups in mean AR or QOL scores. A reduction in neutrophil elastase concentration was associated with reduced symptoms. Conclusions Elimination diets guided by leucocyte activation tests reduced symptoms. These findings could lead to insights into the pathophysiology of IBS. Trial registration number NCT02186743. PMID:29018540
Kanazawa, M; Palsson, O S; van Tilburg, M A L; Gangarosa, L M; Fukudo, S; Whitehead, W E
2014-05-01
Acute intestinal infection leads to persistent intestinal smooth muscle hypercontractility and pain hypersensitivity after resolution of the infection in animal models. We investigated whether postinfectious irritable bowel syndrome (PI-IBS) is associated with abnormalities in phasic contractions of the colon, smooth muscle tone, and pain sensitivity compared to non-PI-IBS (NI-IBS) or healthy controls (HC). Two hundred and eighteen Rome III-positive IBS patients and 43 HC participated. IBS patients were designated PI-IBS, if their IBS symptoms began following an episode of gastroenteritis characterized by two or more of: fever, vomiting, or diarrhea. Pain threshold to phasic distentions of the descending colon was assessed using a barostat. Colonic motility was assessed with the barostat bag minimally inflated to the individual operating pressure (IOP), at 20 mmHg above the IOP, and following a test meal. IBS symptom severity and psychological symptoms were assessed by the IBS Severity Scale (IBS-SS) and the Brief Symptom Inventory-18 (BSI-18). Twenty two (10.1%) met criteria for PI-IBS. Both IBS and HC groups showed a significant increase in motility index during intraluminal distention and following meals. The magnitude of the response to distention above (orad to) the balloon was significantly greater in PI-IBS compared with NI-IBS (p < 0.05) or HC (p < 0.01). Differences between PI-IBS and NI-IBS were not significant for IBS symptom severity, pain threshold, barostat bag volumes, or any psychological score on the BSI-18. Patients with PI-IBS have greater colonic hypercontractility than NI-IBS. We speculate that sustained mild mucosal inflammation may cause this colonic irritability. © 2014 John Wiley & Sons Ltd.
Kanazawa, Motoyori; Palsson, Olafur S.; van Tilburg, Miranda A.L.; Gangarosa, Lisa M.; Fukudo, Shin; Whitehead., William E.
2015-01-01
Background Acute intestinal infection leads to persistent intestinal smooth muscle hypercontractility and pain hypersensitivity after resolution of the infection in animal models. We investigated whether post-infectious irritable bowel syndrome (PI-IBS) is associated with abnormalities in phasic contractions of the colon, smooth muscle tone and pain sensitivity compared to non-PI-IBS (NI-IBS) or healthy controls (HC). Methods 218 Rome III positive IBS patients and 43 healthy controls participated. IBS patients were designated PI-IBS if their IBS symptoms began following an episode of gastroenteritis characterized by 2 or more of: fever, vomiting, or diarrhea. Pain threshold to phasic distentions of the descending colon was assessed using a barostat. Colonic motility was assessed with the barostat bag minimally inflated to the individual operating pressure (IOP), at 20 mmHg above the IOP, and following a test meal. IBS symptom severity and psychological symptoms were assessed by the IBS Severity Scale (IBS-SS) and the Brief Symptom Inventory-18 (BSI-18). Key Results Twenty-two (10.1%) met criteria for PI-IBS. Both IBS and HC groups showed a significant increase in motility index during intraluminal distention and following meals. The magnitude of the response to distention above (orad to) the balloon was significantly greater in PI-IBS compared with NI-IBS (p<0.05) or HC (p<0.01). Differences between PI-IBS and NI-IBS were not significant for IBS symptom severity, pain threshold, barostat bag volumes, or any psychological score on the BSI-18. Conclusions & Inferences Patients with PI-IBS have greater colonic hypercontractility than NI-IBS. We speculate that sustained mild mucosal inflammation may cause this colonic irritability. PMID:24602083
NASA Astrophysics Data System (ADS)
Fakhar-E-Alam, Muhammad; Akram, M. Waseem; Iqbal, Seemab; Alimgeer, K. S.; Atif, M.; Sultana, K.; Willander, M.; Wang, Zhiming M.
2017-04-01
Carcinogenesis is a complex molecular process starting with genetic and epigenetic alterations, mutation stimulation, and DNA modification, which leads to proteomic adaptation ending with an uncontrolled proliferation mechanism. The current research focused on the empirical modelling of the physiological response of human melanoma cells (FM55P) and human foreskin fibroblasts cells (AG01518) to the multilayer zinc oxide (ZnO) nanomaterials under UV-A exposure. To validate this experimental scheme, multilayer ZnO nanomaterials were grown on a femtotip silver capillary and conjugated with protoporphyrin IX (PpIX). Furthermore, PpIX-conjugated ZnO nanomaterials grown on the probe were inserted into human melanoma (FM55P) and foreskin fibroblasts cells (AG01518) under UV-A light exposure. Interestingly, significant cell necrosis was observed because of a loss in mitochondrial membrane potential just after insertion of the femtotip tool. Intense reactive oxygen species (ROS) fluorescence was observed after exposure to the ZnO NWs conjugated with PpIX femtotip model under UV exposure. Results were verified by applying several experimental techniques, e.g., ROS detection, MTT assay, and fluorescence spectroscopy. The present work reports experimental modelling of cell necrosis in normal human skin as well as a cancerous tissue. These obtained results pave the way for a more rational strategy for biomedical and clinical applications.
Taylor, C; Duffy, L K; Plumley, F G; Bowyer, R T
2000-09-01
A spectrofluorometric method (B. Grandchamp et al., 1980, Biochem. Biophys. Acta 629, 577-586) developed for the determination of amounts of uroporphyrin I (Uro I), coproporphyrin III (Copro III), and protoporphyrin IX (Proto IX) in skin fibroblasts was compared with a high-performance liquid chromatography (HPLC) method for the analysis of porphyrins in fecal samples of river otters (Lutra canadensis). Heptacarboxylate porphyrin I and coproporphyrin I, two porphyrins determined to be critical in defining the porphyrin profile in fecal samples of river otters with the HPLC method, contributed substantially to the calculation of the concentrations of Uro I and Copro III, respectively, in standard solutions of porphyrins with the spectrofluorometric method. Fluorescent components of the fecal matrix complicated the determination of the concentrations of Uro I, Copro III, and Proto IX with the spectrofluorometric method and resulted in erroneous values for the concentrations of these porphyrins compared with values determined with the HPLC method. These results indicate that the complexity of the sample, particularly with regard to the potential presence of interfering fluorescent compounds, as well as porphyrins additional to Uro I, Copro III, and Proto IX, should be considered prior to the application of the spectrofluorometric method. An alternative HPLC method developed for the rapid characterization of porphyrin profiles in fecal samples of river otters is described. Copyright 2000 Academic Press.
YOUNG STELLAR POPULATIONS IN MYStIX STAR-FORMING REGIONS: CANDIDATE PROTOSTARS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Romine, Gregory; Feigelson, Eric D.; Getman, Konstantin V.
The Massive Young Star-Forming Complex in Infrared and X-ray (MYStIX) project provides a new census on stellar members of massive star-forming regions within 4 kpc. Here the MYStIX Infrared Excess catalog and Chandra -based X-ray photometric catalogs are mined to obtain high-quality samples of Class I protostars using criteria designed to reduce extragalactic and Galactic field star contamination. A total of 1109 MYStIX Candidate Protostars (MCPs) are found in 14 star-forming regions. Most are selected from protoplanetary disk infrared excess emission, but 20% are found from their ultrahard X-ray spectra from heavily absorbed magnetospheric flare emission. Two-thirds of the MCP sample ismore » newly reported here. The resulting samples are strongly spatially associated with molecular cores and filaments on Herschel far-infrared maps. This spatial agreement and other evidence indicate that the MCP sample has high reliability with relatively few “false positives” from contaminating populations. But the limited sensitivity and sparse overlap among the infrared and X-ray subsamples indicate that the sample is very incomplete with many “false negatives.” Maps, tables, and source descriptions are provided to guide further study of star formation in these regions. In particular, the nature of ultrahard X-ray protostellar candidates without known infrared counterparts needs to be elucidated.« less
Comprehensive functional analysis of N-linked glycans on Ebola virus GP1.
Lennemann, Nicholas J; Rhein, Bethany A; Ndungo, Esther; Chandran, Kartik; Qiu, Xiangguo; Maury, Wendy
2014-01-28
Ebola virus (EBOV) entry requires the virion surface-associated glycoprotein (GP) that is composed of a trimer of heterodimers (GP1/GP2). The GP1 subunit contains two heavily glycosylated domains, the glycan cap and the mucin-like domain (MLD). The glycan cap contains only N-linked glycans, whereas the MLD contains both N- and O-linked glycans. Site-directed mutagenesis was performed on EBOV GP1 to systematically disrupt N-linked glycan sites to gain an understanding of their role in GP structure and function. All 15 N-glycosylation sites of EBOV GP1 could be removed without compromising the expression of GP. The loss of these 15 glycosylation sites significantly enhanced pseudovirion transduction in Vero cells, which correlated with an increase in protease sensitivity. Interestingly, exposing the receptor-binding domain (RBD) by removing the glycan shield did not allow interaction with the endosomal receptor, NPC1, indicating that the glycan cap/MLD domains mask RBD residues required for binding. The effects of the loss of GP1 N-linked glycans on Ca(2+)-dependent (C-type) lectin (CLEC)-dependent transduction were complex, and the effect was unique for each of the CLECs tested. Surprisingly, EBOV entry into murine peritoneal macrophages was independent of GP1 N-glycans, suggesting that CLEC-GP1 N-glycan interactions are not required for entry into this important primary cell. Finally, the removal of all GP1 N-glycans outside the MLD enhanced antiserum and antibody sensitivity. In total, our results provide evidence that the conserved N-linked glycans on the EBOV GP1 core protect GP from antibody neutralization despite the negative impact the glycans have on viral entry efficiency. Filovirus outbreaks occur sporadically throughout central Africa, causing high fatality rates among the general public and health care workers. These unpredictable hemorrhagic fever outbreaks are caused by multiple species of Ebola viruses, as well as Marburg virus. While filovirus vaccines and therapeutics are being developed, there are no licensed products. The sole viral envelope glycoprotein, which is a principal immunogenic target, contains a heavy shield of glycans surrounding the conserved receptor-binding domain. We find that disruption of this shield through targeted mutagenesis leads to an increase in cell entry, protease sensitivity, and antiserum/antibody sensitivity but is not sufficient to allow virion binding to the intracellular receptor NPC1. Therefore, our studies provide evidence that filoviruses maintain glycoprotein glycosylation to protect against proteases and antibody neutralization at the expense of efficient entry. Our results unveil interesting insights into the unique entry process of filoviruses and potential immune evasion tactics of the virus.
Mohammadi, Mojgan; Tahmasebi Abdar, Hossein; Mollaei, Hamid Reza; Hajghani, Hossein; Baneshi, Mohammad Reza; Hayatbakhsh, Mohammad Mahdi
2017-01-01
BACKGROUND Irritable bowel syndrome (IBS) is a digestive system disorder with an unknown etiology. Serotonin has a key role in the secretion and motility of the intestine. Polymorphism in serotonin re-uptake transporter (SERT or SLC6A4) gene may have a functional role in the gut of patients with IBS. The aims of the present study were to investigate the association between SLC6A4 gene polymorphism and IBS and to detect the correlation between rectal serotonin levels and IBS sub-types. METHODS SLC6A4 gene polymorphism in 131 patients with IBS and 211 healthy controls were analysed using the quantitative polymerase chain reaction high-resolution melting (qPCR-HRM) curve technique. Serotonin was measured in rectal biopsies of patients with IBS using the enzyme-linked immunosorbent assay (ELISA) method. RESULTS The patients were categorized into three groups: IBS with diarrhoea (IBS-D): 70 patients, IBS with constipation (IBS-C): 18 patients, and IBS with mixed symptoms (IBS-M): 43 patients. The frequency of SLC6A4 s/s and l/s genotypes was significantly higher in IBS-C than IBS-D, IBS-M, and controls (p=0.036). Serotonin levels were similar in IBS sub-types. CONCLUSION SLC6A4 polymorphism is a possible candidate gene associated with the pathogenesis of IBS-C. Although serotonin levels did not differ in rectal biopsies of IBS sub-types, further investigation is recommended. PMID:28316763
NASA Astrophysics Data System (ADS)
Makhadmeh, Ghaseb N.; Aziz, Azlan Abdul; Razak, Khairunisak Abdul; Al-Akhras, M.-Ali H.
2018-02-01
This study involves the synthesis of Protoporphyrin IX (PpIX) encapsulated with Silica Nanoparticles (SiNPs) as an application for Photodynamic therapy. Semi-rigid artificial tissues with optical features similar to human tissue were used as sample materials to ascertain the efficacy of PpIX encapsulated with SiNPs. The disparity in optical characteristics (transmittance, reflectance, scattering, and absorption) of tissues treated with encapsulated PpIX and naked PpIX under light exposure (Intensity at 408 nm ~1.19 mW/cm2) was explored. The optimal exposure times required for naked PpIX and SiNPs encapsulated PpIX to engulf Red Blood Cells (RBCs) in the artificial tissue were subsequently measured. Comparative analysis showed that the encapsulated PpIX has a 91.5 % higher efficacy than naked PpIX. The results prove the applicability of PpIX encapsulated with SiNP on artificial tissue and possible use on human tissue.
Chung, K S; Madar, D A; Goldsmith, J C; Kingdon, H S; Roberts, H R
1978-01-01
Human Factor IX (Christmas factor) was isolated from the plasma of a patient with mild hemophilia B. The patient's plasma contained 5% Factor IX clotting activity but 100% Factor IX antigenic activity as determined by immunological assays, which included inhibitor neutralization and a radioimmunoassay for Factor IX. This abnormal Factor IX is called Factor IX Chapel Hill (Factor IXCH). Both normal Factor IX and Factor IXCH have tyrosine as the NH2-terminal amino acid. The two proteins have a similar molecular weight, a similar amino acid analysis, the same number of gamma-carboxyglutamic acid residues (10 gamma-carboxyglutamic acid residues), and a similar carbohydrate content. Both exist as a single-chain glycoprotein in plasma. The major difference between normal Factor IX and Factor IXCH is that the latter exhibits delayed activation to Factor IXa in the presence of Factor XIa and Ca2+. Thus, Factor IXCH differs from other previously described abnormal Factor IX molecules. Images PMID:711853
Salas-Cortes, Laura; Ye, Fei; Tenza, Danièle; Wilhelm, Claire; Theos, Alexander; Louvard, Daniel; Raposo, Graça; Coudrier, Evelyne
2005-10-15
Members of at least four classes of myosin (I, II, V and VI) have been implicated in the dynamics of a large variety of organelles. Despite their common motor domain structure, some of these myosins, however, are non processive and cannot move organelles along the actin tracks. Here, we demonstrate in the human pigmented MNT-1 cell line that, (1) the overexpression of one of these myosins, myosin 1b, or the addition of cytochalasin D affects the morphology of the sorting multivesicular endosomes; (2) the overexpression of myosin 1b delays the processing of Pmel17 (the product of murine silver locus also named GP100), which occurs in these multivesicular endosomes; (3) myosin 1b associated with endosomes coimmunoprecipitates with Pmel17. All together, these observations suggest that myosin 1b controls the traffic of protein cargo in multivesicular endosomes most probably through its ability to modulate with actin the morphology of these sorting endosomes.
The role of lectins and glycans in platelet clearance
Hoffmeister, Karin M.
2015-01-01
Summary In recent years, it has become increasingly apparent that the life span of transfused platelets in circulation is regulated, at least in part, by glycan-lectin mediated mechanisms. There is clear evidence that refrigerated platelets are cleared by glycan-lectin mediated clearance mechanisms. Acute platelet cooling clusters glycoprotein (GP) Ibα receptors bearing uncovered N-acetylglucosamine (GlcNAc), and αMβ2 integrins on hepatic macrophages recognise clustered GlcNAc to rapidly clear these platelets from circulation. With prolonged refrigeration GPIbα clustering bearing uncovered galactose increases, which mediates the removal of long-term refrigerated platelets via hepatic Ashwell-Morell receptors (AMR), originally named as asialoglycoprotein receptors. In contrast, little is known about the molecular mechanisms of transfused room temperature platelet clearance. This review examines the role of glycan-lectin mediated clearance of exogenous, i.e. transfused chilled platelet clearance and briefly addresses the current knowledge of stored platelet function, degradation and its relation to platelet clearance. PMID:21781240
Nutritional advice for community patients: insights from a panel discussion.
Thomas, Linda V; Jenkins, Gill; Belton, Julie; Clements, Suzie; Jacob, Ciara; Johnson, Naomi; Joy, Deirdre; Low, Jennifer; Munson, Eileen; Sheppard, Jessica
2016-03-01
This article describes the conclusions of an expert panel that discussed four case studies; these were examples of patients typically encountered by nurses working in the community. The panel considered the nutritional and lifestyle advice that could be given by nurses relating to conditions such as irritable bowel syndrome (IBS), depression, chronic fatigue syndrome, vulnerability to common infections, elderly care, recurrent urinary tract infection, antibiotic use, and risk of type 2 diabetes. A general conclusion was the importance of motivational interviewing techniques in achieving full understanding of patients' concerns and to determine the best health strategy. As well as specific guidance appropriate for each disorder, a range of information sources for both health professionals and patients are listed in the paper. The panel noted that, although general nutritional advice can be given by nurses working at GP surgeries and in the community, patients should always be referred to registered dietitians or nutritionists if significant dietary changes are considered.
Genetics Home Reference: glycogen storage disease type IX
... Health Conditions Glycogen storage disease type IX Glycogen storage disease type IX Printable PDF Open All Close ... to view the expand/collapse boxes. Description Glycogen storage disease type IX (also known as GSD IX) ...
Castro, Rafaela A.; Kubitschek-Barreira, Paula H.; Teixeira, Pedro A. C.; Sanches, Glenda F.; Teixeira, Marcus M.; Quintella, Leonardo P.; Almeida, Sandro R.; Costa, Rosane O.; Camargo, Zoilo P.; Felipe, Maria S. S.; de Souza, Wanderley; Lopes-Bezerra, Leila M.
2013-01-01
Sporotrichosis is a chronic infectious disease affecting both humans and animals. For many years, this subcutaneous mycosis had been attributed to a single etiological agent; however, it is now known that this taxon consists of a complex of at least four pathogenic species, including Sporothrix schenckii and Sporothrix brasiliensis. Gp70 was previously shown to be an important antigen and adhesin expressed on the fungal cell surface and may have a key role in immunomodulation and host response. The aim of this work was to study the virulence, morphometry, cell surface topology and gp70 expression of clinical isolates of S. brasiliensis compared with two reference strains of S. schenckii. Several clinical isolates related to severe human cases or associated with the Brazilian zoonotic outbreak of sporotrichosis were genotyped and clustered as S. brasiliensis. Interestingly, in a murine subcutaneous model of sporotrichosis, these isolates showed a higher virulence profile compared with S. schenckii. A single S. brasiliensis isolate from an HIV-positive patient not only showed lower virulence but also presented differences in cell morphometry, cell wall topography and abundant gp70 expression compared with the virulent isolates. In contrast, the highly virulent S. brasiliensis isolates showed reduced levels of cell wall gp70. These observations were confirmed by the topographical location of the gp70 antigen using immunoelectromicroscopy in both species. In addition, the gp70 molecule was sequenced and identified using mass spectrometry, and the sequenced peptides were aligned into predicted proteins using Blastp with the S. schenckii and S. brasiliensis genomes. PMID:24116065
Moshaverinia, Alireza; Chee, Winston W; Brantley, William A; Schricker, Scott R
2011-03-01
N-vinylcaprolactam (NVC)-containing glass ionomers are promising dental restorative materials with improved mechanical properties; however, little information is available on other physical characteristics of these types of modified glass ionomers, especially their surface properties. Understanding the surface characteristics and behavior of glass ionomers is important for understanding their clinical behavior and predictability as dental restorative materials. The purpose of this study was to investigate the effect of NVC-containing terpolymers on the surface properties and bond strength to dentin of GIC (glass-ionomer cement), and to evaluate the effect of NVC-containing terpolymer as a dentin conditioner. The terpolymer of acrylic acid (AA)-itaconic acid (IA)-N-vinylcaprolactam (NVC) with a molar ratio of 8:1:1 (AA:IA:NVC) was synthesized by free radical polymerization and characterized using nuclear magnetic resonance ((1)H-NMR) and Fourier transform infrared spectroscopy (FTIR). The synthesized terpolymer was used in glass-ionomer cement formulations (Fuji IX GP). Ten disc-shaped specimens (12 × 1 mm) were mixed and fabricated at room temperature. Surface properties (wettability) of modified cements were studied by contact angle measurements as a function of time. Work of adhesion values of different surfaces were also determined. The effect of NVC-modified polyacid on the bond strength of glass-ionomer cement to dentin was investigated. The mean data obtained from contact angle and bonding strength measurements were subjected to t test and 2-way ANOVA (α=.05). NVC-modified glass-ionomer cements showed significantly (P<.05) lower contact angles (46 degrees) and higher work of adhesion (W(A)=60.33 erg/cm(2)) in comparison to commercially available Fuji IX GP (57 degrees and W(A)=53.01 erg/cm(2)). The wettability of dentin surfaces conditioned with NVC-containing terpolymer was significantly higher (P<.05) (22 degrees, WA=73.77 erg/cm(2)) than dentin conditioned with GC dentin conditioner (29 degrees, W(A)=70.52 erg/cm(2)). The experimental cement also showed significantly higher values for shear bond strength to dentin (8.7 ±0.15 MPa after 1 month) when compared to the control group (8.4 ±0.13 MPa after 1 month). NVC-containing terpolymers may enhance the surface properties of GICs and increase their bond strength to the dentin. Furthermore, NVC-containing polyelectrolytes are better dentin conditioners than a commercially available dentin conditioner (GC dentin conditioner). Copyright © 2011 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.
Makhadmeh, Ghaseb Naser; Abdul Aziz, Azlan; Abdul Razak, Khairunisak; Abu Noqta, Osama
2015-12-01
This study analysed the physical effects of Cichorium Pumilum (CP), as a natural photosensitizer (PS), and Protoporphyrin IX (PpIX), as a synthetic PS, encapsulated with silica nanoparticles (SiNPs) in photodynamic therapy. The optimum concentrations of CP and PpIX, needed to destroy Red Blood Cells (RBC), were determined and the efficacy of encapsulated CP and PpIX were compared with naked CP and PpIX was verified. The results confirmed the applicability of CP and PpIX encapsulated in SiNPs on RBCs, and established a relationship between the encapsulated CP and PpIX concentration and the time required to rupture 50% of the RBCs (t50). The CP and PpIX encapsulated in SiNPs exhibited higher efficacy compared with that of naked CP and PpIX, respectively, and CP had less efficacy compared with PpIX.
Systemic delivery of factor IX messenger RNA for protein replacement therapy
Ramaswamy, Suvasini; Tonnu, Nina; Tachikawa, Kiyoshi; Limphong, Pattraranee; Vega, Jerel B.; Karmali, Priya P.; Chivukula, Pad; Verma, Inder M.
2017-01-01
Safe and efficient delivery of messenger RNAs for protein replacement therapies offers great promise but remains challenging. In this report, we demonstrate systemic, in vivo, nonviral mRNA delivery through lipid nanoparticles (LNPs) to treat a Factor IX (FIX)-deficient mouse model of hemophilia B. Delivery of human FIX (hFIX) mRNA encapsulated in our LUNAR LNPs results in a rapid pulse of FIX protein (within 4–6 h) that remains stable for up to 4–6 d and is therapeutically effective, like the recombinant human factor IX protein (rhFIX) that is the current standard of care. Extensive cytokine and liver enzyme profiling showed that repeated administration of the mRNA–LUNAR complex does not cause any adverse innate or adaptive immune responses in immune-competent, hemophilic mice. The levels of hFIX protein that were produced also remained consistent during repeated administrations. These results suggest that delivery of long mRNAs is a viable therapeutic alternative for many clotting disorders and for other hepatic diseases where recombinant proteins may be unaffordable or unsuitable. PMID:28202722
A quasi-atomic model of human adenovirus type 5 capsid
Fabry, Céline M S; Rosa-Calatrava, Manuel; Conway, James F; Zubieta, Chloé; Cusack, Stephen; Ruigrok, Rob W H; Schoehn, Guy
2005-01-01
Adenoviruses infect a wide range of vertebrates including humans. Their icosahedral capsids are composed of three major proteins: the trimeric hexon forms the facets and the penton, a noncovalent complex of the pentameric penton base and trimeric fibre proteins, is located at the 12 capsid vertices. Several proteins (IIIa, VI, VIII and IX) stabilise the capsid. We have obtained a 10 Å resolution map of the human adenovirus 5 by image analysis from cryo-electron micrographs (cryoEMs). This map, in combination with the X-ray structures of the penton base and hexon, was used to build a quasi-atomic model of the arrangement of the two major capsid components and to analyse the hexon–hexon and hexon–penton interactions. The secondary proteins, notably VIII, were located by comparing cryoEM maps of native and pIX deletion mutant virions. Minor proteins IX and IIIa are located on the outside of the capsid, whereas protein VIII is organised with a T=2 lattice on the inner face of the capsid. The capsid organisation is compared with the known X-ray structure of bacteriophage PRD1. PMID:15861131
Effects of two natural medicine formulations on irritable bowel syndrome symptoms: a pilot study.
Hawrelak, Jason A; Myers, Stephen P
2010-10-01
The study objective was to assess the effects and tolerability of two novel natural medicine formulations in improving bowel habit and abdominal symptoms in patients with irritable bowel syndrome (IBS). The DA-IBS formula was designed to treat diarrhea-predominant and alternating bowel habit IBS, and the C-IBS formula was designed to treat constipation-predominant IBS. This was a two arm, open-label, uncontrolled pilot study. Subjects were recruited from the greater Lismore area (NSW, Australia) in 2001. The study included 31 patients who fulfilled the Rome II criteria for IBS. Twenty-one (21) patients were classified as suffering from diarrhea-predominant or alternating bowel habit IBS and 10 patients were classified with constipation-predominant IBS. The DA-IBS formula consisted of a mixture of dried, powdered bilberry fruit, slippery elm bark, agrimony aerial parts, and cinnamon quills. The C-IBS formula consisted of a mixture of dried powdered slippery elm bark, lactulose, oat bran, and licorice root. The aim of each formula was to normalize stool frequency and stool consistency. Ingestion of the DA-IBS formula was associated with a small, but significant increase in bowel movement frequency (p = 0.027). Subjects in the DA-IBS group also experienced reductions in straining (p = 0.004), abdominal pain (p = 0.006), bloating (p < 0.0001), flatulence (p = 0.0001), and global IBS symptoms (p = 0.002) during the treatment phase of the trial. Subjects in the C-IBS group experienced a 20% increase in bowel movement frequency (p = 0.016) and significant reductions in straining (p < 0.0001), abdominal pain (p = 0.032), bloating (p = 0.034), and global IBS symptom severity (p = 0.0005), as well as improvements in stool consistency (p < 0.0001). Both formulas were well-tolerated. The DA-IBS formula was not effective in improving bowel habit in individuals with diarrhea-predominant or alternating bowel habit IBS, although it did significantly improve a number of IBS symptoms. The C-IBS formula significantly improved both bowel habit and IBS symptoms in patients with constipation-predominant IBS. Further research is warranted on C-IBS, as a potentially useful therapeutic formula.
Ma, Hongyan; Darmawan, Erica T.; Zhang, Min; Zhange, Lei; Bryers, James D.
2013-01-01
Traditional antibiotic therapy to control medical device-based infections typically fails to clear biofilm infections and may even promote the evolution of antibiotic resistant species. We report here the development of two novel antibiofilm agents; gallium (Ga) or zinc (Zn) complexed with protoporphyrin IX (PP) or mesoprotoporphyrin IX (MP) that are both highly effective in negating suspended bacterial growth and biofilm formation. These chelated gallium or zinc complexes act as iron siderophore analogs, surplanting the natural iron uptake of most bacteria. Poly (ether urethane) (PEU; Biospan®) polymer films were fabricated for the controlled sustained release of the Ga- or Zn-complexes, using an incorporated pore-forming agent, poly (ethylene glycol) (PEG). An optimum formulation containing 8% PEG (MW=1450) in the PEU polymer effectively sustained drug release for at least 3 months. All drug-loaded PEU films exhibited in vitro ≥ 90% reduction of Gram-positive (Staphylococcus epidermidis) and Gram-negative (Pseudomonas aeruginosa) bacteria in both suspended and biofilm culture versus the negative control PEU films releasing nothing. Cytotoxicity and endotoxin evaluation demonstrated no adverse responses to the Ga- or Zn-complex releasing PEU films. Finally, in vivo studies further substantiate the anti-biofilm efficacy of the PEU films releasing Ga- or Zn- complexes. PMID:24140747
Ma, Hongyan; Darmawan, Erica T; Zhang, Min; Zhang, Lei; Bryers, James D
2013-12-28
Traditional antibiotic therapy to control medical device-based infections typically fails to clear biofilm infections and may even promote the evolution of antibiotic resistant species. We report here the development of two novel antibiofilm agents; gallium (Ga) or zinc (Zn) complexed with protoporphyrin IX (PP) or mesoprotoporphyrin IX (MP) that are both highly effective in negating suspended bacterial growth and biofilm formation. These chelated gallium or zinc complexes act as iron siderophore analogs, supplanting the natural iron uptake of most bacteria. Poly (ether urethane) (PEU; Biospan®) polymer films were fabricated for the controlled sustained release of the Ga- or Zn-complexes, using an incorporated pore-forming agent, poly(ethylene glycol) (PEG). An optimum formulation containing 8% PEG (MW=1450) in the PEU polymer effectively sustained drug release for at least 3months. All drug-loaded PEU films exhibited in vitro ≥ 90% reduction of Gram-positive (Staphylococcus epidermidis) and Gram-negative (Pseudomonas aeruginosa) bacteria in both suspended and biofilm culture versus the negative control PEU films releasing nothing. Cytotoxicity and endotoxin evaluation demonstrated no adverse responses to the Ga- or Zn-complex releasing PEU films. Finally, in vivo studies further substantiate the anti-biofilm efficacy of the PEU films releasing Ga- or Zn- complexes. © 2013.
Shi, Hui; Wan, Jun; Liu, Wenhui; Su, Binbin
2015-04-01
To study the clinical discrepancy between patients with post infectious irritable bowel syndrome (PI-IBS) and non post infectious irritable bowel syndrome (NPI-IBS) , and assess the value of serum intestinal fatty acid binding protein (I-FABP) for differential diagnosis. A total of 117 patients with PI-IBS, 201 patients with NPI-IBS and 31 healthy controls were prospectively recruited in General Liberation Army Hospital from 2010 to 2013. Plasma samples and clinical data were collected. Serum I-FABP level was measured by an enzyme-linked immunosorbent assay. The median age of patients with PI-IBS was 36 years. The median time to diagnosis in PI-IBS group was significantly longer than that in NPI-IBS group [(19.7 ± 10.3)months vs (11.4 ± 5.3) months, P < 0.05]. Similarly, the proportion of anxiety [58.1%(68/117) vs 28.9%(58/201), P < 0.05] and the value of I-FABP [(42.6 ± 14.8) µg/L vs (17.3 ± 11.5) µg/L, P < 0.05] in PI-IBS group were significant higher than NPI-IBS patients. The level of I-FABP of healthy controls [(10.6 ± 8.2) µg/L] was also significantly lower than that of PI-IBS patients (P < 0.05), yet no difference from that of NPI-IBS group. The I-FABP value of subgroup PI-IBS patients with diarrhoea (IBS-D) was significant higher than that of NPI-IBS group [(54.8 ± 9.3)µg/L vs (12.3 ± 6.2) µg/L, P < 0.05]. However, other parameters including gender, age, GSRS score, and I-FABP value of subgroup constipation (IBS-C) and mix (IBS-M), were not different between PI-IBS group and NPI-IBS group (all P > 0.05). PI-IBS is an occult intestinal inflammation disease with mucosa injury. I-FABP might be a potential testing marker for the diagnosis of PI-IBS.
Fujii, Yasushi; Nomura, Shinobu
2008-01-01
Background To investigate non-patient irritable bowel syndrome (IBS) change to IBS and to determine factors predictive of the onset of IBS, individual biological factors, psychological factors, behavioral factors, and environmental factors were examined. Methods The subjects were 105 non-patient IBS (male = 59, female = 46, average age:21.49 ± 2.37), including 68 of the diarrhea-predominant type and 37 of the constipation-predominant type selected from 1,409 university and technical college students by use of a questionnaire based on the Rome II diagnostic criteria. The subjects were followed for three years, and various characteristics and IBS symptoms were serially observed (12 times). The IBS incidence rate was calculated. Results During the three years, 37 non-patient IBS (35.24%) changed to IBS: 28 diarrhea-predominant type and 9 constipation-predominant type. All IBS symptoms disappeared in 26 non-patient IBS subjects (24.76%). According to quantification method II (discriminant analysis), seven factors (stressor, two kinds of stress coping styles, cognitive appraisal, eating habits, sleeping time, and psychologically abuse) were adopted as a predictive model for IBS incidence and were confirmed as predictive of IBS. Conclusion The results of this research show that non-patient IBS is a changeable state that can change into IBS or persons without symptoms. Most of the non-patient IBS subjects who became asymptomatic had had symptoms for six months or less. Furthermore, the longer a non-patient IBS subject had symptoms, the higher the risk of a change to IBS became. The findings suggest the usefulness of identifying and approaching non-patient IBS as early as possible to prevent the onset of IBS. It must be noted that the persons surveyed in the present study had only the diarrhea-predominant and constipation-predominant types. Therefore, the findings of the present study are limited only these two types. Further study including the mixed type is needed. PMID:18817571
Integrated Baseline System (IBS). Version 1.03, System Management Guide
DOE Office of Scientific and Technical Information (OSTI.GOV)
Williams, J.R.; Bailey, S.; Bower, J.C.
This IBS System Management Guide explains how to install or upgrade the Integrated Baseline System (IBS) software package. The IBS is an emergency management planning and analysis tool that was developed under the direction of the Federal Emergency Management Agency (FEMA). This guide includes detailed instructions for installing the IBS software package on a Digital Equipment Corporation (DEC) VAX computer from the IBS distribution tapes. The installation instructions include procedures for both first-time installations and upgrades to existing IBS installations. To ensure that the system manager has the background necessary for successful installation of the IBS package, this guide alsomore » includes information on IBS computer requirements, software organization, and the generation of IBS distribution tapes. When special utility programs are used during IBS installation and setups, this guide refers you to the IBS Utilities Guide for specific instructions. This guide also refers you to the IBS Data Management Guide for detailed descriptions of some IBS data files and structures. Any special requirements for installation are not documented here but should be included in a set of installation notes that come with the distribution tapes.« less
Fufsler, Thomas P.; Castelfranco, Paul A.; Wong, Yum-Shing
1984-01-01
Intact developing chloroplasts isolated from greening cucumber (Cucumis sativus L. var Beit Alpha) cotyledons were found to contain all the enzymes necessary for the synthesis of chlorophyllide. Glutamate was converted to Mg-protoporphyrin IX (monomethyl ester) and protoclorophyllide. δ-Aminolevulinic acid and protoporphyrin IX were converted to Mg-protoporphyrin IX, Mg-protoporphyrin IX monomethyl ester, protochlorophyllide and chlorophyllide a. The conversion of δ-aminolevulinic acid or protoporphyrin IX to Mg-protoporphyrin IX (monomethyl ester) was inhibited by AMP and p-chloromercuribenzene sulfonate. Light stimulated the formation of Mg-protoporphyrin IX from all three substrates. In the case of δ-aminolevulinic acid and protoporphyrin IX, light could be replaced by exogenous ATP. In the case of glutamate, both ATP and reducing power were necessary to replace light. With all three substrates, glutamate, δ-aminolevulinic acid, and protoporphyrin IX, the stimulation of Mg-protoporphyrin IX accumulation in the light was abolished by DCMU, and this DCMU block was overcome by added ATP and reducing power. PMID:16663535
Effects of Disturbed Sleep on Gastrointestinal and Somatic Pain Symptoms in IBS
Patel, Ami; Hasak, Stephen; Cassell, Benjamin; Ciorba, Matthew A.; Vivio, Emily E.; Kumar, Mrudula; Gyawali, C. Prakash; Sayuk, Gregory S.
2016-01-01
Summary Background Sleep disturbances are common, and perhaps are even more prevalent in irritable bowel syndrome (IBS). Aim To determine the effect of measured sleep on: 1) IBS symptoms the following day, and IBS-specific quality of life (IBS-QOL), and 2) non-GI pain symptoms. Methods IBS patients’ sleep patterns were compared to healthy individuals via wrist-mounted actigraphy over 7 days. Daily bowel pain logs (severity, distress; 10-point Likert), stool pattern (Bristol scale) and supporting symptoms (e.g., bloating, urgency; 5-point Likert) were kept. Validated measures, including the GI Symptom Rating Scale-IBS, Visceral Sensitivity Index, Pittsburgh Sleep Quality Index and the IBS-Quality of Life were collected. Mediation analysis explored the relationship between sleep, mood, and bowel symptoms. Results 50 subjects (38.6±1.0years old, 44 female; 24 IBS and 26 healthy controls) completed sleep monitoring. IBS patients slept more hours per day (7.7±0.2 vs 7.1±0.1, p=0.008), but felt less well-rested. IBS patients demonstrated more waking episodes during sleep (waking episodes; 12.1 vs 9.3, p<0.001). Waking episodes predicted worse abdominal pain (p≤0.01) and GI distress (p<0.001), but not bowel pattern or accessory IBS symptoms (p>0.3 for each). Waking episodes negatively correlated with general- and IBS-specific QOL in IBS (r= −0.58 and −0.52, p<0.001 for each). Disturbed sleep effects on abdominal pain were partially explained by mood as an intermediate. Conclusion Sleep disturbances are more common in IBS, and correlate with IBS-related pain, distress, and poorer IBS-related QOL. Disturbed sleep effects extend beyond the bowel, leading to worse mood and greater somatic pain in IBS patients. PMID:27240555
Anxiety and IBS revisited: ten years later.
Popa, Stefan-Lucian; Dumitrascu, Dan Lucian
2015-01-01
Irritable bowel syndrome (IBS) has been associated with high prevalence of psychological and psychiatric disorders. However, the association between IBS and each of its subtypes (diarrhea IBS-D, constipation IBS-C, mixed IBS-M) with anxiety still remains unclear. The purpose of this study was to perform a comparative analysis of the association between anxiety and IBS on a period of ten years. PubMed was searched for studies analyzing IBS and anxiety, published at 10 years interval. The study presents a comparative analysis of the articles that were published between 2003-2005 and 2013-2015, investigating the correlation between anxiety and IBS. The initial search identified 220 articles, from which 156 were published between 2013 and 2015, and 64 were published between 2003 and 2005. Of these articles, 15 articles were included in the review. Out of these 15 articles, 10 articles analyzed the correlation between anxiety-depression status in IBS patients using specific questionnaires, 2 articles analyzed genetic variables in IBS, 1 article analyzed serotonin and monoamine oxidase levels in IBS, 1 article analyzed serum levels of IL-1β and IL-10 in IBS, 1 article analyzed somatostatin and vasoactive intestinal peptide levels in IBS. The result was a review of 15 studies that analyzed the association between IBS and anxiety. IBS is a heterogeneous disorder caused by numerous psychological, immunological, infectious, endocrine and genetic factors. In recent years, the number of studies concentrating on genetic factors, cytokines and hormones has increased in comparison with the 2003-2005 period, when clinical investigation, using mainly questionnaires was the essential method. Also, the total number of papers investigating anxiety and IBS, considerably increased. The recent studies have confirmed the fact that IBS symptoms are often exacerbated during stressful events and the psychiatric treatment has a positive effect on gastro-intestinal symptomatology.
2013-01-01
Background Diarrhea-predominant irritable bowel syndrome (IBS-d) significantly diminishes the health-related quality of life (HRQOL) of patients. Psychological and social impacts are common with many IBS-d patients reporting comorbid depression, anxiety, decreased intimacy, and lost working days. The Irritable Bowel Syndrome Quality of Life (IBS-QOL) questionnaire is a 34-item instrument developed and validated for measurement of HRQOL in non-subtyped IBS patients. The current paper assesses this previously-validated instrument employing data collected from 754 patients who participated in a randomized clinical trial of a novel treatment, eluxadoline, for IBS-d. Methods Psychometric methods common to HRQOL research were employed to evaluate the IBS-QOL. Many of the historical analyses of the IBS-QOL validations were used. Other techniques that extended the original methods were applied where more appropriate for the current dataset. In IBS-d patients, we analyzed the items and substructure of the IBS-QOL via item reduction, factor structure, internal consistency, reproducibility, construct validity, and ability to detect change. Results This study supports the IBS-QOL as a psychometrically valid measure. Factor analyses suggested that IBS-specific QOL as measured by the IBS-QOL is a unidimensional construct. Construct validity was further buttressed by significant correlations between IBS-QOL total scores and related measures of IBS-d severity including the historically-relevant Irritable Bowel Syndrome Adequate Relief (IBS-AR) item and the FDA’s Clinical Responder definition. The IBS-QOL also showed a significant ability to detect change as evidenced by analysis of treatment effects. A minority of the items, unrelated to the IBS-d, performed less well by the standards set by the original authors. Conclusions We established that the IBS-QOL total score is a psychometrically valid measure of HRQOL in IBS-d patients enrolled in this study. Our analyses suggest that the IBS-QOL items demonstrate very good construct validity and ability to detect changes due to treatment effects. Furthermore, our analyses suggest that the IBS-QOL items measure a univariate construct and we believe further modeling of the IBS-QOL from an item response theory (IRT) approach under both non-treatment and treatment conditions would greatly further our understanding as item-based methods could be used to develop a short form. PMID:24330412
Marczuk-Kolada, Grażyna; Łuczaj-Cepowicz, Elżbieta; Pawińska, Małgorzata; Hołownia, Adam
2017-10-01
Dentistry materials are the most frequently used substitutes of human tissues. Therefore, an assessment of dental filling materials should cover not only their chemical, physical, and mechanical characteristics, but also their cytotoxicity. To compare the cytotoxic effects of 13 conventional glass ionomer cements on human gingival fibroblasts. The assessment was conducted using the MTT test. Six samples were prepared for each material. Culture plates with cells and inserts with the materials were incubated at 37°C, 5% CO2, and 95% humidity for 24 h. Then the inserts were removed, 1 mL of MTT was added in the amount of 0.5 mg/1 mL of the medium, and the samples were incubated in the described conditions without light for 2 h. The optical density was measured with an absorption spectrophotometer at a wavelength of 560 nm. The cytotoxic effects of the Argion Molar was significantly stronger than the Fuji Triage (p = 0.007), Chemfil Molar (p < 0.0001), and Ionofil Molar AC Quick (p < 0.001). The Fuji IX GP and Fuji IX Extra had a significantly stronger adverse effect than the Chemfil Molar (p = 0.014, p = 0.029, respectively) and Ionofil Molar AC Quick (p = 0.017, p = 0.034, respectively). The cements from the low cytotoxicity group were significantly more toxic vs materials whose presence resulted in fibroblast growth (p < 0.001). The research conducted indicates that, although the materials studied may belong to the same group, they are characterized by low, yet not uniform, cytotoxicity on human gingival fibroblasts. The toxic effects should not be assigned to a relevant group of materials, but each dentistry product should be evaluated individually.
Jarrett, M E; Han, C J; Cain, K C; Burr, R L; Shulman, R J; Barney, P G; Naliboff, B D; Zia, J; Heitkemper, M M
2016-07-01
Irritable bowel syndrome (IBS) is a heterogeneous condition with a number of pathophysiological mechanisms that appear to contribute to symptom chronicity. One of these is altered pain sensitivity. Women between ages 18-45 were recruited the community. Of those enrolled, 56 had IBS and 36 were healthy control (HC) women. Participants completed questionnaires, kept a 4-week symptom diary and had a 12-h Holter placed to assess nighttime heart rate variability including high frequency power (HF), low frequency power (LF), and total power (TP). At mid-follicular phase approximately 80% of women completed a thermal pain sensitivity test with conditioned pain modulation and visceral pain sensitivity using a water load symptom provocation (WLSP) test. As expected, daily abdominal pain was significantly higher in the IBS compared to HC group. There were no differences between the bowel pattern subgroups (IBS-diarrhea [IBS-D], IBS-constipation plus mixed [IBS-CM]). Thermal pain sensitivity did not differ between the IBS and the HC groups, but was significantly higher in the IBS-CM group than the IBS-D group. In the WLSP test, the IBS group experienced significantly more symptom distress than HCs and the IBS-CM group was higher than the IBS-D group. Heart rate variability indicators did not differ between the groups or IBS subgroups. Daily abdominal pain was positively correlated with LF and TP in the IBS group. Despite similar levels of abdominal pain in IBS, the IBS-CM group demonstrated greater sensitivity to both thermal and visceral testing procedures. © 2016 John Wiley & Sons Ltd.
Comparison of the Rome IV and Rome III criteria for IBS diagnosis: A cross-sectional survey.
Bai, Tao; Xia, Jing; Jiang, Yudong; Cao, Huan; Zhao, Yong; Zhang, Lei; Wang, Huan; Song, Jun; Hou, Xiaohua
2017-05-01
The aims of this study were to investigate the proportion of clinical irritable bowel syndrome (IBS) at a tertiary hospital in China, to compare the Rome III and Rome IV criteria with regard to IBS diagnosis, to describe the agreement between the Rome III and Rome IV criteria, and to identify differences between Rome IV-positive and -negative IBS patients. A cross-sectional survey was performed among outpatients in the gastrointestinal (GI) department of a tertiary hospital. The patients were categorized as having IBS using Rome III and Rome IV criteria. In total, 1,376 (91.7%) patients completed a GI symptom questionnaire. Among them, 352 were suspected of having IBS and 175 were diagnosed with IBS using the Rome III or Rome IV criteria. In particular, 170 (12.4%) patients were diagnosed with IBS using the Rome III criteria, and 84 (6.1%) patients were diagnosed using the Rome IV criteria. Rome IV IBS patients experienced more pain symptoms (P<0.01) and showed higher IBS severity scores. In contrast, no significant differences were noted for demographic characteristics, stool frequency, IBS subtype, disease course, operation history or GI infection history between Rome IV IBS patients and IBS patients not diagnosed with the Rome IV criteria. Rome IV-positive IBS patients represented approximately half of Rome III-positive IBS patients at a tertiary hospital in China. More specifically, Rome IV-positive IBS was mainly a subgroup of Rome III-positive IBS with more serious symptoms. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.
Svastova, Eliska; Witarski, Wojciech; Csaderova, Lucia; Kosik, Ivan; Skvarkova, Lucia; Hulikova, Alzbeta; Zatovicova, Miriam; Barathova, Monika; Kopacek, Juraj; Pastorek, Jaromir; Pastorekova, Silvia
2012-01-01
Carbonic anhydrase IX (CA IX) is a hypoxia-induced cell surface enzyme expressed in solid tumors, and functionally involved in acidification of extracellular pH and destabilization of intercellular contacts. Since both extracellular acidosis and reduced cell adhesion facilitate invasion and metastasis, we investigated the role of CA IX in cell migration, which promotes the metastatic cascade. As demonstrated here, ectopically expressed CA IX increases scattering, wound healing and transwell migration of MDCK cells, while an inactive CA IX variant lacking the catalytic domain (ΔCA) fails to do so. Correspondingly, hypoxic HeLa cells exhibit diminished migration upon inactivation of the endogenous CA IX either by forced expression of the dominant-negative ΔCA variant or by treatment with CA inhibitor, implying that the catalytic activity is indispensable for the CA IX function. Interestingly, CA IX improves cell migration both in the absence and presence of hepatocyte growth factor (HGF), an established inducer of epithelial-mesenchymal transition. On the other hand, HGF up-regulates CA IX transcription and triggers CA IX protein accumulation at the leading edge of lamellipodia. In these membrane regions CA IX co-localizes with sodium bicarbonate co-transporter (NBCe1) and anion exchanger 2 (AE2) that are both components of the migration apparatus and form bicarbonate transport metabolon with CA IX. Moreover, CA IX physically interacts with AE2 and NBCe1 in situ, as shown here for the first time. Thus, our findings suggest that CA IX actively contributes to cell migration via its ability to facilitate ion transport and pH control at protruding fronts of moving cells. PMID:22170054
Lefkowitz, J B; Monroe, D M; Kasper, C K; Roberts, H R
1993-07-01
A subset of hemophilia B patients have a prolonged bovine-brain prothrombin time. These CRM+ patients are classified as having hemophilia Bm. The prolongation of the prothrombin time has been reported only with bovine brain (referred to as ox brain in some literature) as the source of thromboplastin; prothrombin times determined with thromboplastin from rabbit brain or human brain are not reported to be prolonged. Factor IX from a hemophilia Bm patient (factor IX Hilo) was isolated. The activity of factor IX Hilo was compared to that of normal factor IX in prothrombin time assays when the thromboplastin source was of bovine, rabbit, or human origin. Factor IX, either normal or Hilo, prolonged a prothrombin time regardless of the tissue factor source. However, unless thromboplastin was from a bovine source, this prolongation required high concentrations of factor IX. Further, factor IX normal was as effective as factor IX Hilo in prolonging the prothrombin time when rabbit or human thromboplastin was used. With bovine thromboplastin, factor IX Hilo was significantly better than factor IX normal at prolonging the prothrombin time. The amount of prolongation was dependent on the amount of factor IX Hilo added. In addition, the prolongation was dependent on the concentration of factor X present in the sample. The prothrombin time changed as much as 20 seconds when the factor X concentration was varied from 50% to 150% to normal (fixed concentration of factor IX Hilo). These results demonstrate the difficulty of classifying the severity of a hemophilia Bm patient based on the bovine brain prothrombin time unless both the factor IX and factor X concentrations are known.
Tanaka, Atsunari; Shimizu, Toru
2008-12-16
Phosphodiesterase (Ec DOS) from Escherichia coli is a gas-sensor enzyme in which binding of gas molecules, such as O(2), CO, and NO, to the Fe(II)-protoporphyrin IX complex in the sensor domain stimulates phosphodiesterase activity toward cyclic-di-GMP. In this study, we report that external axial ligands, such as cyanide or imidazole, bind to Fe(III)-protoporphyrin IX in the sensor domain and induce a 10- to 11-fold increase (from 8.1 up to 86 min(-1)) in catalysis, which is more substantial than that (6.3 to 7.2-fold) observed for other gas-stimulated Fe(II) heme-bound enzymes. Catalytic activity (50 min(-1)) of the heme-free mutant, H77A, was comparable to that of the ligand-stimulated enzymes. Accordingly, we propose that the heme at the sensor domain inhibits catalysis and that ligand binding to the heme iron complex releases this catalytic suppression. Furthermore, mutations of Met95, Arg97, and Phe113 at the putative heme distal side suppressed the ligand effects on catalysis. The rate constants (19,000 x 10(-5) microM(-1)min(-1)) for cyanide binding to the M95A and M95L mutants of the full-length enzyme were 633-fold higher than that to wild-type Ec DOS (30 x 10(-5) microM(-1)min(-1)). The absorption spectrum of the F113Y mutant suggests that the Tyr O(-) group directly coordinates to the Fe(III) complex and that the cyanide binding rate to the mutant is very slow, compared with those of the wild-type and other mutant proteins. We observed a similar trend in the binding behavior of imidazole to full-length mutant enzymes. Therefore, while Met95 and Phe113 are not direct axial ligands for the Fe(III) complex, catalytic, spectroscopic, and ligand binding evidence suggests that these residues are located in the vicinity of the heme.
Angeli, Andrea; di Cesare Mannelli, Lorenzo; Trallori, Elena; Peat, Thomas S; Ghelardini, Carla; Carta, Fabrizio; Supuran, Claudiu T
2018-05-10
A series of novel selenides bearing benzenesulfonamide moieties was synthesized and investigated for their inhibition on six human (h) carbonic anhydrase (CA, EC 4.2.1.1) isoforms such as the physiologically relevant hCA I, II, VA, VB, VII, and IX and the X-ray complex in adduct with hCA II for some of them investigated. These enzymes are involved in a variety of diseases including glaucoma, retinitis pigmentosa, epilepsy, arthritis, metabolic disorders, and cancer. The investigated compounds showed potent inhibitory action against hCA VA, VII, and IX, in the low nanomolar range, thus making them of interest for the development of isoform-selective inhibitors and as candidates for various biomedical applications.
Evolution of specificity in cartilaginous fish glycoprotein hormones and receptors.
Buechi, Hanna B; Bridgham, Jamie T
2017-05-15
Glycoprotein hormones (GpH) interact very specifically with their receptors to mediate hypothalamic-pituitary-peripheral gland endocrine signaling. Vertebrates typically have three functionally distinct GpH endocrine signaling complexes: follicle-stimulating hormone, luteinizing hormone, and thyroid-stimulating hormone, and their receptors. Each hormone consists of a common α subunit bound to one of three different β subunits. Individual hormone subunits and receptors are present in genomes of early metazoans, and a subset of hormone subunits and receptors has been recently characterized in sea lamprey. However, it remains unclear when the full complement of hormone and receptor protein families first appeared, and when specificity of interactions between GpH hormones and receptors first evolved. Here we present phylogenetic analyses showing that the elephant shark (Callorhinchus milii) genome contains sequences representing the current diversity of all hormone subunits and receptors in these co-evolving protein families. We examined specificity of hormone and receptor interactions using functional assays testing reporter gene activation by elephant shark follicle-stimulating hormone, luteinizing hormone, and thyroid-stimulating hormone receptors. We show highly specific, dose-responsive hormone interactions for all three complexes. Our results suggest that co-evolution of specificity between proteins in these endocrine signaling complexes occurred prior to the divergence of Chondrichthyes from the chordate lineage. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
Blastocystis sp. in Irritable Bowel Syndrome (IBS)--Detection in Stool Aspirates during Colonoscopy.
Ragavan, Nanthiney Devi; Kumar, Suresh; Chye, Tan Tian; Mahadeva, Sanjiv; Shiaw-Hooi, Ho
2015-01-01
Blastocystis is one of the most common gut parasites found in the intestinal tract of humans and animals. Its' association with IBS is controversial, possibly as a result of irregular shedding of parasites in stool and variation in stool detection. We aimed to screen for Blastocystis in colonic stool aspirate samples in adult patients with and without IBS undergoing colonoscopy for various indications and measure the interleukin levels (IL-8, IL-3 and IL-5). In addition to standard stool culture techniques, polymerase chain reaction (PCR) techniques were employed to detect and subtype Blastocystis. All the serum samples collected were subjected for ELISA studies to measure the interleukin levels (IL-8, IL-3 and IL-5). Among 109 (IBS n = 35 and non-IBS n = 74) adults, direct stool examination and culture of colonic aspirates were initially negative for Blastocystis. However, PCR analysis detected Blastocystis in 6 (17%) IBS and 4 (5.5%) non-IBS patients. In the six positive IBS patients by PCR method, subtype 3 was shown to be the most predominant (3/6: 50%) followed by subtype 4 (2/6; 33.3%) and subtype 5 (1/6; 16.6%). IL-8 levels were significantly elevated in the IBS Blasto group and IBS group (p<0.05) compared to non-IBS and non-IBS Blasto group. The level of IL-3 in were seen to be significantly higher in than IBS Blasto group and IBS group (p<0.05) compared to non-IBS. Meanwhile, the IL-5 levels were significantly higher in IBS Blasto group (p<0.05) compared to non-IBS and non-IBS Blasto group. This study implicates that detecting Blastosystis by PCR method using colonic aspirate samples during colonoscopy, suggests that this may be a better method for sample collection due to the parasite's irregular shedding in Blastocystis-infected stools. Patients with IBS infected with parasite showed an increase in the interleukin levels demonstrate that Blastocystis does have an effect in the immune system.
Valdés, Pablo A.; Kim, Anthony; Brantsch, Marco; Niu, Carolyn; Moses, Ziev B.; Tosteson, Tor D.; Wilson, Brian C.; Paulsen, Keith D.; Roberts, David W.; Harris, Brent T.
2011-01-01
Extent of resection is a major goal and prognostic factor in the treatment of gliomas. In this study we evaluate whether quantitative ex vivo tissue measurements of δ-aminolevulinic acid–induced protoporphyrin IX (PpIX) identify regions of increasing malignancy in low- and high-grade gliomas beyond the capabilities of current fluorescence imaging in patients undergoing fluorescence-guided resection (FGR). Surgical specimens were collected from 133 biopsies in 23 patients and processed for ex vivo neuropathological analysis: PpIX fluorimetry to measure PpIX concentrations (CPpIX) and Ki-67 immunohistochemistry to assess tissue proliferation. Samples displaying visible levels of fluorescence showed significantly higher levels of CPpIX and tissue proliferation. CPpIX was strongly correlated with histopathological score (nonparametric) and tissue proliferation (parametric), such that increasing levels of CPpIX were identified with regions of increasing malignancy. Furthermore, a large percentage of tumor-positive biopsy sites (∼40%) that were not visibly fluorescent under the operating microscope had levels of CPpIX greater than 0.1 µg/mL, which indicates that significant PpIX accumulation exists below the detection threshold of current fluorescence imaging. Although PpIX fluorescence is recognized as a visual biomarker for neurosurgical resection guidance, these data show that it is quantitatively related at the microscopic level to increasing malignancy in both low- and high-grade gliomas. This work suggests a need for improved PpIX fluorescence detection technologies to achieve better sensitivity and quantification of PpIX in tissue during surgery. PMID:21798847
Detrital zircon U-Pb reconnaissance of the Franciscan subduction complex in northwestern California
Dimitru, Trevor; Ernst, W. Gary; Hourigan, Jeremy K.; McLaughlin, Robert J.
2015-01-01
In northwestern California, the Franciscan subduction complex has been subdivided into seven major tectonostratigraphic units. We report U-Pb ages of ≈2400 detrital zircon grains from 26 sandstone samples from 5 of these units. Here, we tabulate each unit's interpreted predominant sediment source areas and depositional age range, ordered from the oldest to the youngest unit. (1) Yolla Bolly terrane: nearby Sierra Nevada batholith (SNB); ca. 118 to 98 Ma. Rare fossils had indicated that this unit was mostly 151-137 Ma, but it is mostly much younger. (2) Central Belt: SND; ca. 103 too 53 Ma (but poorly constrained), again mostly younger than previously thought. (3) Yager terrane: distant Idaho batholith (IB); ca. 52 to 50 Ma. Much of the Yager's detritus was shed during major core complex extension and erosion in Idaho that started 53 Ma. An eocene Princeton River-Princeton submarine canyon system transported this detritus to the Great Valley forearc basin and thence to the Franciscan trench. (4) Coastal terrane: mostly IB, ±SNB, ±nearby Cascade arc, ±Nevada Cenozoic ignimbrite belt; 52 to <32 Ma. (5) King Range terrane: dominated by IB and SNB zircons; parts 16-14 Ma based on microfossils. Overall, some Franciscan units are younger than previously thought, making them more compatible with models for the growth of subduction complexes by positive accretion. From ca. 118 to 70 Ma, Franciscan sediments were sourced mainly from the nearby Sierra Nevada region and were isolated from southwestern US and Mexican sources. From 53 to 49 Ma, the Franciscan was sourced from both Idaho and the Sierra Nevada. By 37-32 Ma, input from Idaho had ceased. The influx from Idaho probably reflects major tectonism in Idaho, Oregon, and Washington, plus development of a through-going Princeton River to California, rather than radical changes in the subduction system at the Franciscan trench itself.
Francica, Joseph R.; Varela-Rohena, Angel; Medvec, Andrew; Plesa, Gabriela; Riley, James L.; Bates, Paul
2010-01-01
Many viruses alter expression of proteins on the surface of infected cells including molecules important for immune recognition, such as the major histocompatibility complex (MHC) class I and II molecules. Virus-induced downregulation of surface proteins has been observed to occur by a variety of mechanisms including impaired transcription, blocks to synthesis, and increased turnover. Viral infection or transient expression of the Ebola virus (EBOV) glycoprotein (GP) was previously shown to result in loss of staining of various host cell surface proteins including MHC1 and β1 integrin; however, the mechanism responsible for this effect has not been delineated. In the present study we demonstrate that EBOV GP does not decrease surface levels of β1 integrin or MHC1, but rather impedes recognition by steric occlusion of these proteins on the cell surface. Furthermore, steric occlusion also occurs for epitopes on the EBOV glycoprotein itself. The occluded epitopes in host proteins and EBOV GP can be revealed by removal of the surface subunit of GP or by removal of surface N- and O- linked glycans, resulting in increased surface staining by flow cytometry. Importantly, expression of EBOV GP impairs CD8 T-cell recognition of MHC1 on antigen presenting cells. Glycan-mediated steric shielding of host cell surface proteins by EBOV GP represents a novel mechanism for a virus to affect host cell function, thereby escaping immune detection. PMID:20844579
Simon, Cécile; Barathieu, Karine; Laguerre, Michel; Schmitter, Jean-Marie; Fouquet, Eric; Pianet, Isabelle; Dufourc, Erick J
2003-09-09
The interactions between the B3 (catechin-4alpha,8-catechin) red wine tannin and the human salivary protein fragment IB7(14) (SPPGKPQGPPPQGG) were monitored by (1)H magic angle spinning NMR, circular dichroism, electrospray ionization mass spectrometry, and molecular modeling. It is found that the secondary structure of IB7(14) is made of a type II helix (collagen helix) and random coil. The central glycine 8 appears to act as a flexible rotula separating two helix II regions. Three tannin molecules tightly complex the peptide, without modifying its secondary structure, but seem to reduce its conformational dynamics. The binding dissociation constant is in the millimolar range. B3 tannins with a "tweezers" conformation bind to the hydrophilic side of the saliva peptide, suggesting that the principal driving forces toward association are governed by hydrogen bonding between the carbonyl functions of proline residues and both the phenol and catechol OH groups. These findings are further discussed in the frame of an astringency phenomenon.
Nishigaki, Kazuo; Hanson, Charlotte; Jelacic, Tanya; Thompson, Delores; Ruscetti, Sandra
2005-01-01
Friend spleen focus-forming virus (SFFV) causes rapid erythroleukemia in mice due to expression of its unique envelope glycoprotein, gp55. Erythroid cells expressing SFFV gp55 proliferate in the absence of their normal regulator erythropoietin (Epo) because of constitutive activation of Epo signal transduction pathways. Although SFFV infects many cell types, deregulation of cell growth occurs only when SFFV infects erythroid cells, suggesting that these cells express unique proteins that the virus requires to mediate its biological effects. Not only do erythroid cells express the Epo receptor (EpoR), but those from mice susceptible to SFFV-induced erythroleukemia also express a short form of the receptor tyrosine kinase Stk (sf-Stk). In erythroid cells, SFFV gp55 interacts with the EpoR complex and sf-Stk, leading to activation of the kinase and constitutive activation of signal transducing molecules. In this study, we demonstrate that SFFV gp55 can also deregulate the growth of nonerythroid cells when it is coexpressed with sf-Stk. Expression of SFFV gp55 in rodent fibroblasts engineered to express sf-Stk induced their transformation, as demonstrated by focus formation and anchorage-independent growth in vitro. This transformation by SFFV gp55 requires the kinase activity of sf-Stk and the presence of its extracellular domain but not expression of the EpoR or the tyrosine kinase Jak2, which is required for activation of signal transduction pathways through the EpoR. Thus, expression of SFFV gp55 in nonerythroid cells coexpressing sf-Stk results in their uncontrolled growth, demonstrating a previously unrecognized mechanism for retrovirus transformation of rodent fibroblasts and providing insight into SFFV-induced disease. PMID:16223879
Advances in IBS 2016: A Review of Current and Emerging Data.
Schoenfeld, Philip S
2016-08-01
Irritable bowel syndrome (IBS) is characterized by chronic intermittent abdominal pain and associated diarrhea (IBS-D), constipation (IBS-C), or both. IBS can significantly impact patient function and quality of life. The diagnosis of IBS is based on the presence of characteristic symptoms, the exclusion of concerning features, and selected tests to exclude organic diseases that can mimic IBS. The pathophysiology of IBS remains incompletely understood, and new contributing factors have been identified over the past decade. Altered gut immune activation, intestinal permeability, and the intestinal and colonic microbiome may be important factors. Poorly absorbed carbohydrates have been implicated in triggering IBS symptoms. Increasing evidence supports the benefit of a diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs). Although there are several randomized controlled trials of probiotics in IBS, they are typically poorly designed and have not consistently demonstrated efficacy. Until recently, there were few effective treatments for IBS-D. Data from recent clinical trials support the use of rifaximin, eluxadoline, and peppermint oil. Options for the treatment of IBS-C include lubiprostone and linaclotide.
Advances in IBS 2016: A Review of Current and Emerging Data
Schoenfeld, Philip S.
2016-01-01
Irritable bowel syndrome (IBS) is characterized by chronic intermittent abdominal pain and associated diarrhea (IBS-D), constipation (IBS-C), or both. IBS can significantly impact patient function and quality of life. The diagnosis of IBS is based on the presence of characteristic symptoms, the exclusion of concerning features, and selected tests to exclude organic diseases that can mimic IBS. The pathophysiology of IBS remains incompletely understood, and new contributing factors have been identified over the past decade. Altered gut immune activation, intestinal permeability, and the intestinal and colonic microbiome may be important factors. Poorly absorbed carbohydrates have been implicated in triggering IBS symptoms. Increasing evidence supports the benefit of a diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs). Although there are several randomized controlled trials of probiotics in IBS, they are typically poorly designed and have not consistently demonstrated efficacy. Until recently, there were few effective treatments for IBS-D. Data from recent clinical trials support the use of rifaximin, eluxadoline, and peppermint oil. Options for the treatment of IBS-C include lubiprostone and linaclotide. PMID:28070176
Funaki, Yasushi; Kaneko, Hiroshi; Kawamura, Yurika; Yoshimine, Takashi; Tamura, Yasuhiro; Izawa, Shinya; Ebi, Masahide; Ogasawara, Naotaka; Sasaki, Makoto; Kasugai, Kunio
2017-01-01
Irritable bowel syndrome (IBS) frequently coexists with non-erosive reflux disease (NERD). Efficacy of long-term proton pump inhibitor (PPI) treatment on NERD with or without IBS is controversial. The impact of comorbid IBS in NERD on quality of life (QOL) remains uncertain. We verified the hypothesis that NERD patients with IBS symptoms demonstrated poor responses to long-term PPI treatments, deteriorated QOL, and high frequency of psychological deviations in Japan. In all, 141 NERD patients who had been taking PPIs for more than 6 months were enrolled and analyzed. Patient profiles were assessed by GerdQ, IBS Severity Index (IBSSI-J)/Gastrointestinal Symptoms Rating Scale (GSRS)/SF-8, and Hospital Anxiety and Depression Scale (HADS). IBS existed in 37 out of 141 NERD patients. Patients with IBS (the positive-IBS group) demonstrated significantly higher frequencies of extant reflux symptoms than those without IBS (64.9 vs. 40.4%). In the positive-IBS group, 40.5% were classified as middle grade by IBSSI-J. The SF-8 and GSRS scores in this group were significantly lower than those without IBS (the negative-IBS group). Prevalence of depression and anxiety by HADS in the positive-IBS group was significantly higher than that in the negative-IBS group. These results proved the hypothesis that considering comorbid IBS among NERD patients on long-term PPI seems recommended in Japan. © 2017 S. Karger AG, Basel.
Fichna, Jakub; Wood, Jodianne T; Papanastasiou, Malvina; Vadivel, Subramanian K; Oprocha, Piotr; Sałaga, Maciej; Sobczak, Marta; Mokrowiecka, Anna; Cygankiewicz, Adam I; Zakrzewski, Piotr K; Małecka-Panas, Ewa; Krajewska, Wanda M; Kościelniak, Piotr; Makriyannis, Alexandros; Storr, Martin A
2013-01-01
Irritable bowel syndrome (IBS) is a functional gastrointestinal (GI) disorder, associated with alterations of bowel function, abdominal pain and other symptoms related to the GI tract. Recently the endogenous cannabinoid system (ECS) was shown to be involved in the physiological and pathophysiological control of the GI function. The aim of this pilot study was to investigate whether IBS defining symptoms correlate with changes in endocannabinoids or cannabinoid like fatty acid levels in IBS patients. AEA, 2-AG, OEA and PEA plasma levels were determined in diarrhoea-predominant (IBS-D) and constipation-predominant (IBS-C) patients and were compared to healthy subjects, following the establishment of correlations between biolipid contents and disease symptoms. FAAH mRNA levels were evaluated in colonic biopsies from IBS-D and IBS-C patients and matched controls. Patients with IBS-D had higher levels of 2AG and lower levels of OEA and PEA. In contrast, patients with IBS-C had higher levels of OEA. Multivariate analysis found that lower PEA levels are associated with cramping abdominal pain. FAAH mRNA levels were lower in patients with IBS-C. IBS subtypes and their symptoms show distinct alterations of endocannabinoid and endocannabinoid-like fatty acid levels. These changes may partially result from reduced FAAH expression. The here reported changes support the notion that the ECS is involved in the pathophysiology of IBS and the development of IBS symptoms.
Serebruany, Victor L; Miller, Michael; Pokov, Alex N; Lynch, Donald; Jensen, Jesper K; Hallén, Jonas; Atar, Dan
2011-01-01
Prescription omega-3-acid ethyl esters (PO-3A) have been tested for outcome benefits in patients with coronary artery disease (CAD), arrhythmias and heart failure. Some evidence suggests that PO-3A may exert their benefit via inhibiting platelets. We tested the hypothesis that PO-3A may inhibit platelet activity in patients with documented stable CAD, beyond the antiplatelet properties of aspirin and statins. Thirty patients with documented CAD and triglycerides over 250 mg/dl treated with aspirin (70-160 mg/daily) and statins (simvastatin equivalence dose: 5-40 mg/daily) were randomized 1:1:1 to Omacor™ 1 g/day (DHA/EPA ratio 1.25:1.0), Omacor 2 g/day, or a placebo for 2 weeks. Platelet tests including aggregometry and flow cytometry and cartridge analyzer readings were performed at baseline and at 1 and 2 weeks following PO-3A therapy. ADP-induced platelet aggregation (p = 0.037), GP IIb/IIIa antigen (p = 0.031) and activity (p = 0.024), and P-selectin (p = 0.041) were significantly reduced after PO-3A, while platelet/endothelial cell adhesion molecule (p = 0.09), vitronectin receptor (p = 0.16), formation of platelet-monocyte microparticles (p = 0.19) and the VerifyNow IIb/IIIa test (p = 0.27) only exhibited nonsignificant trends suggestive of reduced platelet activity. Finally, collagen- and arachidonic acid-induced aggregation, closure time with the PFA-100 device and expression of thrombospondin (CD36), GP Ib (CD42b), LAMP-3 (CD63), LAMP-1 (CD107a), CD40-ligand (CD154), GP37 (CD165), and PAR-1 receptor intact (SPAN 12) and cleaved (WEDE-15) epitopes were not affected by 2 weeks of PO-3A. Independently of the dose and already at 1 week, short-term therapy with PO-3A provided a modest reduction of platelet activity biomarkers, despite concomitant aspirin and statin therapy, when compared to a placebo. The effect of PO-3A is unique, differs from other known antiplatelet agents and suggests potential pleiotropism. These preliminary randomized data call for confirmation in prospective studies. Copyright © 2011 S. Karger AG, Basel.
Valdés, Pablo A.; Moses, Ziev B.; Kim, Anthony; Belden, Clifford J.; Wilson, Brian C.; Paulsen, Keith D.; Roberts, David W.; Harris, Brent T.
2012-01-01
In recent years, 5-aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) fluorescence guidance has been used as a surgical adjunct to improve the extent of resection of gliomas. Exogenous administration of ALA prior to surgery leads to the accumulation of red fluorescent PpIX in tumor tissue that the surgeon can visualize and thereby discriminate between normal and tumor tissue. Selective accumulation of PpIX has been linked to numerous factors, of which blood-brain barrier (BBB) breakdown has been suggested to be a key factor. To test the hypothesis that PpIX concentration (CPpIX) positively correlates with gadolinium (Gd) concentrations (CGd), we performed ex vivo measurements of PpIX and of Gd using Inductively-Coupled Plasma Mass Spectrometry (ICP-MS) the latter as a quantitative biomarker of BBB breakdown; this was corroborated with immunohistochemistry of microvascular density in surgical biopsies of patients undergoing fluorescence guided surgery for glioma .We found positive correlations between CPpIX and CGd (r = 0.58, p < 0.0001), and between CPpIX and microvascular density (r = 0.55, p < 0.0001), suggesting a significant, yet limited association between BBB breakdown and ALA-induced PpIX fluorescence. To our knowledge, this is the first time that Gd measurements by ICP-MS have been used in human gliomas. PMID:22878664
Generation and Characterization of Protective Antibodies to Marburg Virus
2017-04-03
of cells following viral replication of the complex. The macaque developed increasing anti-GP Ab titers as evaluated by ELISA with a titer of 1:12800...those of the author and are not necessarily endorsed by the U.S. Army. SUPPLEMENTAL DATA: Table S-1. ELISA serum titer response following each...x 400 µL at 0.9x109 VRP/mL ELISA Titer (GP) NT >1/316,000 1/500,000 NT ELISA Titer (Live Virus) NT >1/316,000 1/450,000 NT Table S-2
2016-06-14
characterize FVM04 binding to EBOV GP, FVM04 Fab in complex with GP∆Muc was analyzed by negative stain electron microscopy. The binding location of...FVM04 revealed an epitope consistent with the crest region residues derived by mutagenesis studies. The class averages suggest that only one FVM04 Fab ...binds to each GP trimer (Figure 3A-B). It is likely that the binding orientation and proximity to the threefold axis precludes additional FVM04 Fabs
45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation \\1\\
Code of Federal Regulations, 2010 CFR
1998-10-01
... 45 Public Welfare 1 1998-10-01 1998-10-01 false Subject Index to Title IX Preamble and Regulation \\1\\ Index Subject Index to Title IX Preamble and Regulation \\1\\ GENERAL ADMINISTRATION... FINANCIAL ASSISTANCE Procedures [Interim] Interim procedures. Pt. 86, Index Subject Index to Title IX...
45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation \\1\\
Code of Federal Regulations, 2010 CFR
1997-10-01
... 45 Public Welfare 1 1997-10-01 1997-10-01 false Subject Index to Title IX Preamble and Regulation \\1\\ Index Subject Index to Title IX Preamble and Regulation \\1\\ GENERAL ADMINISTRATION... FINANCIAL ASSISTANCE Procedures [Interim] Interim procedures. Pt. 86, Index Subject Index to Title IX...
Chiu, Isaac M; Barrett, Lee B; Williams, Erika K; Strochlic, David E; Lee, Seungkyu; Weyer, Andy D; Lou, Shan; Bryman, Gregory S; Roberson, David P; Ghasemlou, Nader; Piccoli, Cara; Ahat, Ezgi; Wang, Victor; Cobos, Enrique J; Stucky, Cheryl L; Ma, Qiufu; Liberles, Stephen D; Woolf, Clifford J
2014-01-01
The somatosensory nervous system is critical for the organism's ability to respond to mechanical, thermal, and nociceptive stimuli. Somatosensory neurons are functionally and anatomically diverse but their molecular profiles are not well-defined. Here, we used transcriptional profiling to analyze the detailed molecular signatures of dorsal root ganglion (DRG) sensory neurons. We used two mouse reporter lines and surface IB4 labeling to purify three major non-overlapping classes of neurons: 1) IB4+SNS-Cre/TdTomato+, 2) IB4−SNS-Cre/TdTomato+, and 3) Parv-Cre/TdTomato+ cells, encompassing the majority of nociceptive, pruriceptive, and proprioceptive neurons. These neurons displayed distinct expression patterns of ion channels, transcription factors, and GPCRs. Highly parallel qRT-PCR analysis of 334 single neurons selected by membership of the three populations demonstrated further diversity, with unbiased clustering analysis identifying six distinct subgroups. These data significantly increase our knowledge of the molecular identities of known DRG populations and uncover potentially novel subsets, revealing the complexity and diversity of those neurons underlying somatosensation. DOI: http://dx.doi.org/10.7554/eLife.04660.001 PMID:25525749
EEHG Performance and Scaling Laws
DOE Office of Scientific and Technical Information (OSTI.GOV)
Penn, Gregory
This note will calculate the idealized performance of echo-enabled harmonic generation performance (EEHG), explore the parameter settings, and look at constraints determined by incoherent synchrotron radiation (ISR) and intrabeam scattering (IBS). Another important effect, time-of-flight variations related to transverse emittance, is included here but without detailed explanation because it has been described previously. The importance of ISR and IBS is that they lead to random energy shifts that lead to temporal shifts after the various beam manipulations required by the EEHG scheme. These effects give competing constraints on the beamline. For chicane magnets which are too compact for a givenmore » R56, the magnetic fields will be sufficiently strong that ISR will blur out the complex phase space structure of the echo scheme to the point where the bunching is strongly suppressed. The effect of IBS is more omnipresent, and requires an overall compact beamline. It is particularly challenging for the second pulse in a two-color attosecond beamline, due to the long delay between the first energy modulation and the modulator for the second pulse.« less
Abdulmajeed, Ahmed; Rabab, Mohamed A; Sliem, Hamdy A; Hebatallah, Nour Eldein
2011-01-01
Introduction Irritable bowel syndrome (IBS) is one of the most common disorders diagnosed by gastroenterologists and a common cause of general practice visits. Although this disease is not life threatening, patients with IBS seem to be seriously affected in their everyday life. The study was designed to explore the pattern of IBS in clinical practice and the impact on the quality of life. Methods This is a case control descriptive study. 117 individuals were included in this study. Rome II criteria were used for the diagnosis of IBS. Impact of IBS on patient's quality of life was determined by irritable bowel syndrome quality of life (IBS-QOL) questionnaire. Results Prevalence of IBS among the study sample was 34.2%. 10% were IBS-Diarrhea, 37.5% were IBS-Constipation and 52.5% were alternators. There is statistical insignificant relationship between IBS (+) and age while it was a significant relation regarding gender (more common among women 80%). There is statistical significance relationship between IBS (+) on one hand and marital status and occupational status on the other hand. Patients with IBS had statistically significant lower scores for all IBS- QOL domains compared with the control group. Conclusion IBS is a prevalent disorder that affects females more than males and it has significant impacts on work, lifestyle and social well-being. PMID:22145053
Abdulmajeed, Ahmed; Rabab, Mohamed A; Sliem, Hamdy A; Hebatallah, Nour Eldein
2011-01-01
Irritable bowel syndrome (IBS) is one of the most common disorders diagnosed by gastroenterologists and a common cause of general practice visits. Although this disease is not life threatening, patients with IBS seem to be seriously affected in their everyday life. The study was designed to explore the pattern of IBS in clinical practice and the impact on the quality of life. This is a case control descriptive study. 117 individuals were included in this study. Rome II criteria were used for the diagnosis of IBS. Impact of IBS on patient's quality of life was determined by irritable bowel syndrome quality of life (IBS-QOL) questionnaire. Prevalence of IBS among the study sample was 34.2%. 10% were IBS-Diarrhea, 37.5% were IBS-Constipation and 52.5% were alternators. There is statistical insignificant relationship between IBS (+) and age while it was a significant relation regarding gender (more common among women 80%). There is statistical significance relationship between IBS (+) on one hand and marital status and occupational status on the other hand. Patients with IBS had statistically significant lower scores for all IBS- QOL domains compared with the control group. IBS is a prevalent disorder that affects females more than males and it has significant impacts on work, lifestyle and social well-being.
The Structure of Carbonic Anhydrase IX Is Adapted for Low-pH Catalysis.
Mahon, Brian P; Bhatt, Avni; Socorro, Lilien; Driscoll, Jenna M; Okoh, Cynthia; Lomelino, Carrie L; Mboge, Mam Y; Kurian, Justin J; Tu, Chingkuang; Agbandje-McKenna, Mavis; Frost, Susan C; McKenna, Robert
2016-08-23
Human carbonic anhydrase IX (hCA IX) expression in many cancers is associated with hypoxic tumors and poor patient outcome. Inhibitors of hCA IX have been used as anticancer agents with some entering Phase I clinical trials. hCA IX is transmembrane protein whose catalytic domain faces the extracellular tumor milieu, which is typically associated with an acidic microenvironment. Here, we show that the catalytic domain of hCA IX (hCA IX-c) exhibits the necessary biochemical and biophysical properties that allow for low pH stability and activity. Furthermore, the unfolding process of hCA IX-c appears to be reversible, and its catalytic efficiency is thought to be correlated directly with its stability between pH 3.0 and 8.0 but not above pH 8.0. To rationalize this, we determined the X-ray crystal structure of hCA IX-c to 1.6 Å resolution. Insights from this study suggest an understanding of hCA IX-c stability and activity in low-pH tumor microenvironments and may be applicable to determining pH-related effects on enzymes.
a Calorimetric Study of the Precipitation Hardening Mechanisms in AN Al-Cu-Mg-Si Alloy
NASA Astrophysics Data System (ADS)
Hayoune, Abdelali
2013-08-01
The precipitation phenomena and the related hardening in an Al-Cu-Mg-Si alloy were studied by calorimetry, X-ray diffraction analysis and microhardness measurements. The main calorimetric peaks were identified to be due to β‧‧, θ‧ and Q‧ phases precipitation. The hardening during aging at room temperature and 160°C, was respectively, explained by atomic clusters and GP zones formation and by GP zones and β‧‧/θ‧ phases coprecipitation. Although the mechanical properties variation during aging at 200°C is simple, the corresponding microstructural evolution is complex: on the basis of the DSC results, the increasing of microhardness values, is mainly due to the coprecipitation of GP zones and β‧‧/θ‧ phases, however, the maximum hardening is explained by the coexistence of β‧‧/θ‧ and θ‧‧ phases. Another important conclusion is that during aging at 160°C and 200°C, the θ‧ phase is essentially developed from GP zones.
Li, Juan; Tao, Shujuan; Orlando, Ron; Murtaugh, Michael P.
2015-01-01
Porcine reproductive and respiratory syndrome virus (PRRSV) is a positive-sense ssRNA virus whose envelope contains four glycoproteins and three nonglycosylated proteins. Glycans of major envelope glycoprotein 5 (GP5) are proposed as important for virus assembly and entry into permissive cells. Structural characterization of GP5 glycans would facilitate the mechanistic understanding of these processes. Thus, we purified the PRRSV type 2 prototype strain, VR2332, and analyzed the virion-associated glycans by both biochemical and mass spectrometric methods. Endoglycosidase digestion showed that GP5 was the primary protein substrate, and that the carbohydrate moieties were primarily complex-type N-glycans. Mass spectrometric analysis (HPLC-ESI-MS/MS) of GP5 N-glycans revealed an abundance of N-acetylglucosamine (GlcNAc) and N-acetyllactosamine (LacNAc) oligomers in addition to sialic acids. GlcNAc and LacNAc accessibility to ligands was confirmed by lectin co-precipitation. Our findings help to explain PRRSV infection of cells lacking sialoadhesin and provide a glycan database to facilitate molecular structural studies of PRRSV. PMID:25726973
Comparison of N- and O-linked glycosylation patterns of ebolavirus glycoproteins.
Collar, Amanda L; Clarke, Elizabeth C; Anaya, Eduardo; Merrill, Denise; Yarborough, Sarah; Anthony, Scott M; Kuhn, Jens H; Merle, Christine; Theisen, Manfred; Bradfute, Steven B
2017-02-01
Ebolaviruses are emerging pathogens that cause severe and often fatal viral hemorrhagic fevers. Four distinct ebolaviruses are known to cause Ebola virus disease in humans. The ebolavirus envelope glycoprotein (GP 1,2 ) is heavily glycosylated, but the precise glycosylation patterns of ebolaviruses are largely unknown. Here we demonstrate that approximately 50 different N-glycan structures are present in GP 1,2 derived from the four pathogenic ebolaviruses, including high mannose, hybrid, and bi-, tri-, and tetra-antennary complex glycans with and without fucose and sialic acid. The overall N-glycan composition is similar between the different ebolavirus GP 1,2 s. In contrast, the amount and type of O-glycan structures varies widely between ebolavirus GP 1,2 s. Notably, this O-glycan dissimilarity is also present between two variants of Ebola virus, the original Yambuku variant and the Makona variant responsible for the most recent Western African epidemic. The data presented here should serve as the foundation for future ebolaviral entry and immunogenicity studies. Copyright © 2016 Elsevier Inc. All rights reserved.
Smad7 enables STAT3 activation and promotes pluripotency independent of TGF-β signaling
Yu, Yi; Gu, Shuchen; Li, Wenjian; Sun, Chuang; Chen, Fenfang; Xiao, Mu; Wang, Lei; Xu, Dewei; Li, Ye; Ding, Chen; Xia, Zongping; Li, Yi; Ye, Sheng; Xu, Pinglong; Zhao, Bin; Qin, Jun; Chen, Ye-Guang; Lin, Xia; Feng, Xin-Hua
2017-01-01
Smad7 is a negative feedback product of TGF-β superfamily signaling and fine tunes a plethora of pleiotropic responses induced by TGF-β ligands. However, its noncanonical functions independent of TGF-β signaling remain to be elucidated. Here, we show that Smad7 activates signal transducers and activators of transcription 3 (STAT3) signaling in maintaining mouse embryonic stem cell pluripotency in a manner independent of the TGF-β receptors, yet dependent on the leukemia inhibitory factor (LIF) coreceptor glycoprotein 130 (gp130). Smad7 directly binds to the intracellular domain of gp130 and disrupts the SHP2–gp130 or SOCS3–gp130 complex, thereby amplifying STAT3 activation. Consequently, Smad7 facilitates LIF-mediated self-renewal of mouse ESCs and is also critical for induced pluripotent stem cell reprogramming. This finding illustrates an uncovered role of the Smad7–STAT3 interplay in maintaining cell pluripotency and also implicates a mechanism involving Smad7 underlying cytokine-dependent regulation of cancer and inflammation. PMID:28874583
Ethylene Response Factors Are Controlled by Multiple Harvesting Stresses in Hevea brasiliensis
Putranto, Riza-Arief; Duan, Cuifang; Kuswanhadi; Chaidamsari, Tetty; Rio, Maryannick; Piyatrakul, Piyanuch; Herlinawati, Eva; Pirrello, Julien; Dessailly, Florence; Leclercq, Julie; Bonnot, François; Tang, Chaorong; Hu, Songnian; Montoro, Pascal
2015-01-01
Tolerance of recurrent mechanical wounding and exogenous ethylene is a feature of the rubber tree. Latex harvesting involves tapping of the tree bark and ethephon is applied to increase latex flow. Ethylene is an essential element in controlling latex production. The ethylene signalling pathway leads to the activation of Ethylene Response Factor (ERF) transcription factors. This family has been identified in Hevea brasiliensis. This study set out to understand the regulation of ERF genes during latex harvesting in relation to abiotic stress and hormonal treatments. Analyses of the relative transcript abundance were carried out for 35 HbERF genes in latex, in bark from mature trees and in leaves from juvenile plants under multiple abiotic stresses. Twenty-one HbERF genes were regulated by harvesting stress in laticifers, revealing an overrepresentation of genes in group IX. Transcripts of three HbERF-IX genes from HbERF-IXc4, HbERF-IXc5 and HbERF-IXc6 were dramatically accumulated by combining wounding, methyl jasmonate and ethylene treatments. When an ethylene inhibitor was used, the transcript accumulation for these three genes was halted, showing ethylene-dependent induction. Subcellular localization and transactivation experiments confirmed that several members of HbERF-IX are activator-type transcription factors. This study suggested that latex harvesting induces mechanisms developed for the response to abiotic stress. These mechanisms probably depend on various hormonal signalling pathways. Several members of HbERF-IX could be essential integrators of complex hormonal signalling pathways in Hevea. PMID:25906196
Fluorescence spectroscopy of gastrointestinal tumors using δ-ALA
NASA Astrophysics Data System (ADS)
Borisova, E. G.; Vladimirov, B. G.; Angelov, I. G.; Avramov, L. A.
2007-03-01
In the recent study delta-aminolevulinic acid/Protoporphyrin IX (δ-ALA/PpIX) is used as fluorescent marker for dysplasia and tumor detection in esophagus and stomach. The δ-ALA is administered per os six hours before measurements at dose 20mg/kg weight. High-power light-emitting diode at 405 nm is used as an excitation source. Special opto-mechanical device is built to use the light guide of standard video-endoscopic system (Olimpus Corp.). Through endoscopic instrumental channel a fiber is applied to return information about fluorescence to microspectrometer (USB4000, OceanOptics Inc.). The fluorescence detected from tumor sites has very complex spectral origins. It consists of autofluorescence, fluorescence from exogenous fluorophores and re-absorption from the chromophores accumulated in the tissue investigated. Mucosa autofluorescence lies at 450-600 nm region. The fluorescence of PpIX is clearly pronounced at the 630-710 nm region. Deep minima in the tumor fluorescence signals are observed in the region 540-575 nm, related to hemoglobin re-absorption. Such high hemoglobin content is an indication of the tumors neovascularisation and it is clearly pronounced in all dysplastic and tumor sites investigated. The lack of fluorescence peaks in the red spectral area for normal mucosa is an indication for selective accumulation of δ-ALA/PpIX only in abnormal sites and gives high contrast when lesion borders are determined from clinicians during video observation in the process of diagnostic procedure. Very good correlation between fluorescence signals and histology examination results of the lesions investigated is achieved.
A Comparison of Genetic Programming Variants for Hyper-Heuristics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Harris, Sean
Modern society is faced with ever more complex problems, many of which can be formulated as generate-and-test optimization problems. General-purpose optimization algorithms are not well suited for real-world scenarios where many instances of the same problem class need to be repeatedly and efficiently solved, such as routing vehicles over highways with constantly changing traffic flows, because they are not targeted to a particular scenario. Hyper-heuristics automate the design of algorithms to create a custom algorithm for a particular scenario. Hyper-heuristics typically employ Genetic Programming (GP) and this project has investigated the relationship between the choice of GP and performance inmore » Hyper-heuristics. Results are presented demonstrating the existence of problems for which there is a statistically significant performance differential between the use of different types of GP.« less
Robert, Amélie; Boyer, Lucie; Pineault, Nicolas
2011-03-01
The development of culture processes for hematopoietic progenitors could lead to the development of a complementary source of platelets for therapeutic purposes. However, functional characterization of culture-derived platelets remains limited, which raises some uncertainties about the quality of platelets produced in vitro. The aim of this study was to define the proportion of functional platelets produced in cord blood CD34+ cell cultures. Toward this, the morphological and functional properties of culture-derived platelet-like particles (PLPs) were critically compared to that of blood platelets. Flow cytometry combined with transmission electron microscopy analyses revealed that PLPs formed a more heterogeneous population of platelets at a different stage of maturation than blood platelets. The majority of PLPs harbored the fibrinogen receptor αIIbβ3, but a significant proportion failed to maintain glycoprotein (GP)Ibα surface expression, a component of the vWF receptor essential for platelet functions. Importantly, GPIbα extracellular expression correlated closely with platelet function, as the GPIIb+ GPIbα+ PLP subfraction responded normally to agonist stimulation as evidenced by α-granule release, adhesion, spreading, and aggregation. In contrast, the GPIIb+ GPIbα⁻ subfraction was unresponsive in most functional assays and appeared to be metabolically inactive. The present study confirms that functional platelets can be generated in cord blood CD34+ cell cultures, though these are highly susceptible to ectodomain shedding of receptors associated with loss of function. Optimization of culture conditions to prevent these deleterious effects and to homogenize PLPs is necessary to improve the quality and yields of culture-derived platelets before they can be recognized as a suitable complementary source for therapeutic purposes.
Goñi, Pilar; Almagro-Nievas, Diego; Cieloszyk, Joanna; Lóbez, Silvia; Navarro-Marí, José María; Gutiérrez-Fernández, José
2015-12-01
This work describes the genetic characterization of Cryptosporidium and Giardia involved in an outbreak in a nursery school in Granada, Spain, that affected seven children under the age of 4. Nucleic acids were extracted from the seven stool samples positive to Cryptosporidium or Giardia by microscopy and/or immunochromatography. The species and subtypes of Cryptosporidium were identified by PCR-RFLP and PCR of the SSUrRNA and gp60 genes, respectively. The assemblages of Giardia duodenalis isolates were characterized by PCR of the tpi gene. PCR products were sequenced and analyzed. All of the isolates were positive for Cryptosporidium hominis. Five of them belonged to subtype IaA11R2, one to subtype IbA10G2R2, and the other could not be identified. Three of these samples were positive for G. duodenalis by PCR, two belonging to the assemblage A, and the other one to assemblage B. This is the first report of Cryptosporidium hominis subtype IaA11R2 as a cause of an outbreak in Europe where subtype IbA10G2R2 is the most frequently identified. In the case of Giardia, an outbreak could not be confirmed because of the low number of positive samples and the low genetic variability of the amplified fragments for assemblage A of tpi gene. A new subtype, of Cryptosporidium hominis named IaA11R2, has been described as a cause of an outbreak in a nursery school in Granada, Spain. However an outbreak of giardiasis could not be confirmed. Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.
2013-01-01
Background Biologically active inclusion bodies (IBs) have gained much attention in recent years. Fusion with IB-inducing partner has been shown to be an efficient strategy for generating active IBs. To make full use of the advantages of active IBs, one of the key issues will be to improve the activity yield of IBs when expressed in cells, which would need more choices on IB-inducing fusion partners and approaches for engineering IBs. Green fluorescent protein (GFP) has been reported to aggregate when overexpressed, but GFP fusion has not been considered as an IB-inducing approach for these fusion proteins so far. In addition, the role of linker in fusion proteins has been shown to be important for protein characteristics, yet impact of linker on active IBs has never been reported. Results Here we report that by fusing GFP and acid phosphatase PhoC via a linker region, the resultant PhoC-GFPs were expressed largely as IBs. These IBs show high levels of specific fluorescence and specific PhoC activities (phosphatase and phosphotransferase), and can account for up to over 80% of the total PhoC activities in the cells. We further demonstrated that the aggregation of GFP moiety in the fusion protein plays an essential role in the formation of PhoC-GFP IBs. In addition, PhoC-GFP IBs with linkers of different flexibility were found to exhibit different levels of activities and ratios in the cells, suggesting that the linker region can be utilized to manipulate the characteristics of active IBs. Conclusions Our results show that active IBs of PhoC can be generated by GFP fusion, demonstrating for the first time the potential of GFP fusion to induce active IB formation of another soluble protein. We also show that the linker sequence in PhoC-GFP fusion proteins plays an important role on the regulation of IB characteristics, providing an alternative and important approach for engineering of active IBs with the goal of obtaining high activity yield of IBs. PMID:23497261
Glioplasticity in irritable bowel syndrome.
Lilli, N L; Quénéhervé, L; Haddara, S; Brochard, C; Aubert, P; Rolli-Derkinderen, M; Durand, T; Naveilhan, P; Hardouin, J-B; De Giorgio, R; Barbara, G; Bruley des Varannes, S; Coron, E; Neunlist, M
2018-04-01
Growing evidence indicates a wide array of cellular remodeling in the mucosal microenvironment during irritable bowel syndrome (IBS), which possibly contributes to pathophysiology and symptom generation. Here, we investigated whether enteric glial cells (EGC) may be altered, and which factors/mechanisms lead to these changes. Colonic mucosal biopsies of IBS patients (13 IBS-Constipation [IBS-C]; 10 IBS-Diarrhea [IBS-D]; 11 IBS-Mixed [IBS-M]) and 24 healthy controls (HC) were analyzed. Expression of S100β and GFAP was measured. Cultured rat EGC were incubated with supernatants from mucosal biopsies, then proliferation and Ca 2+ response to ATP were analyzed using flow cytometry and Ca 2+ imaging. Histamine and histamine 1-receptor (H1R) involvement in the effects of supernatant upon EGC was analyzed. Compared to HC, the mucosal area immunoreactive for S100β was significantly reduced in biopsies of IBS patients, independently of the IBS subtype. IBS-C supernatants reduced EGC proliferation and IBS-D and IBS-M supernatants reduced Ca 2+ response to ATP in EGC. EGC expressed H1R and the effects of supernatant upon Ca 2+ response to ATP in EGC were blocked by pyrilamine and reproduced by histamine via H1R. IBS supernatants reduced mRNA expression of connexin-43. The S100β-stained area was negatively correlated with the frequency and intensity of pain and bloating. Changes in EGC occur in IBS, involving mucosal soluble factors. Histamine, via activation of H1R-dependent pathways, partly mediates altered Ca 2+ response to ATP in EGC. These changes may contribute to the pathophysiology and the perception of pain and bloating in patients with IBS. © 2017 John Wiley & Sons Ltd.
Park, S H; Naliboff, B D; Shih, W; Presson, A P; Videlock, E J; Ju, T; Kilpatrick, L; Gupta, A; Mayer, E A; Chang, L
2018-01-01
Irritable bowel syndrome (IBS) is a stress-sensitive disorder associated with early adverse life events (EALs) and a dysregulated hypothalamic-pituitary-adrenal (HPA) axis. Resilience is the ability to recover and adapt positively to stress but has not been well studied in IBS. The aims of this study are to compare resilience in IBS and healthy controls (HCs) and to assess its relationships with IBS symptom severity, quality of life (QOL), EALs, and HPA axis response. Two hundred fifty-six subjects (154 IBS, 102 HCs) completed questionnaires for resilience (Connor-Davidson Resilience Scale [CD-RISC] and Brief Resilience Scale [BRS]), IBS symptoms, IBS-QOL, and EALs. Ninety-six of these subjects had serial serum adrenocorticotropic hormone (ACTH) and cortisol levels to exogenous corticotrophin-releasing hormone (CRH) and ACTH measured. The relationship between IBS status, resilience, and other variables of interest was assessed by regression analysis after adjusting for demographics and neuroticism, a predictor of resilience. Resilience was significantly lower in IBS compared to HCs (CD-RISC: 72.16±14.97 vs 77.32±12.73, P=.003; BRS: 3.29±0.87 vs 3.93±0.69, P<.001); however, only BRS was significant after controlling for neuroticism (P=.001). Lower BRS scores were associated with greater IBS symptom severity (P=.002), poorer IBS-QOL (P<.001), and a higher number of EALs (P=.01). There was a significant interaction between BRS resilience and IBS status for ACTH-stimulated cortisol response (P=.031); more resilient IBS subjects had lower cortisol response, and more resilient HCs had higher cortisol response. Lower resilience is associated with IBS status, worse IBS symptom severity, lower IBS-QOL, greater EALs, and stress hyperresponsiveness. © 2017 John Wiley & Sons Ltd.
Ehealth: Low FODMAP diet vs Lactobacillus rhamnosus GG in irritable bowel syndrome
Pedersen, Natalia; Andersen, Nynne Nyboe; Végh, Zsuzsanna; Jensen, Lisbeth; Ankersen, Dorit Vedel; Felding, Maria; Simonsen, Mette Hestetun; Burisch, Johan; Munkholm, Pia
2014-01-01
AIM: To investigate the effects of a low fermentable, oligosaccharides, disaccharides, monosaccharides and polyols diet (LFD) and the probiotic Lactobacillus rhamnosus GG (LGG) in irritable bowel syndrome (IBS). METHODS: Randomised, unblinded controlled trial on the effect of 6-wk treatment with LFD, LGG or a normal Danish/Western diet (ND) in patients with IBS fulfilling Rome III diagnostic criteria, recruited between November 2009 and April 2013. Patients were required to complete on a weekly basis the IBS severity score system (IBS-SSS) and IBS quality of life (IBS-QOL) questionnaires in a specially developed IBS web self-monitoring application. We investigated whether LFD or LGG could reduce IBS-SSS and improve QOL in IBS patients. RESULTS: One hundred twenty-three patients (median age 37 years, range: 18-74 years), 90 (73%) females were randomised: 42 to LFD, 41 to LGG and 40 to ND. A significant reduction in mean ± SD of IBS-SSS from baseline to week 6 between LFD vs LGG vs ND was revealed: 133 ± 122 vs 68 ± 107, 133 ± 122 vs 34 ± 95, P < 0.01. Adjusted changes of IBS-SSS for baseline covariates showed statistically significant reduction of IBS-SSS in LFD group compared to ND (IBS-SSS score 75; 95%CI: 24-126, P < 0.01), but not in LGG compared to ND (IBS-SSS score 32; 95%CI: 18-80, P = 0.20). IBS-QOL was not altered significantly in any of the three groups: mean ± SD in LFD 8 ± 18 vs LGG 7 ± 17, LFD 8 ± 18 vs ND 0.1 ± 15, P = 0.13. CONCLUSION: Both LFD and LGG are efficatious in patients with IBS. PMID:25473176
Jonefjäll, Börje; Simrén, Magnus; Öhman, Lena; Lasson, Anders; Svedlund, Jan; Strid, Hans
2015-09-01
Symptoms compatible with irritable bowel syndrome (IBS) are common in patients with ulcerative colitis (UC) in clinical remission. It has been suggested that these symptoms might arise due to post-inflammatory changes comparable with post-infectious IBS. The aim was to study factors at new onset of UC that predict development of IBS-like symptoms during clinical remission. In total, 98 patients with new onset of UC were followed prospectively for 3 years with yearly follow-up visits. Data from the first visit at the onset of UC were compared between a group of patients who fulfilled the criteria for IBS while in remission (UCR+IBS) during follow-up and a group who did not (UCR-IBS). Among the UC patients, 87 met the criteria for clinical remission and 25 (29%) of these reported IBS-like symptoms in remission during follow-up. There was no difference in inflammatory disease activity at the initial flare or in the prevalence of previous IBS symptoms when comparing UCR+IBS and UCR-IBS patients. The UCR+IBS patients reported more severe gastrointestinal symptoms, including abdominal pain, during their primary flare. The severity and extent of inflammation at onset of UC do not seem to affect the development of IBS-like symptoms in UC patients during clinical remission. The high prevalence of IBS-like symptoms is not explained by pre-existing IBS. UCR+IBS patients reported more severe gastrointestinal symptoms at disease onset, which might indicate a more sensitive gastrointestinal tract in this category of patients. Copyright © 2015 European Crohn’s and Colitis Organisation (ECCO). Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.
Object-based connectedness facilitates matching.
Koning, Arno; van Lier, Rob
2003-10-01
In two matching tasks, participants had to match two images of object pairs. Image-based (IB) connectedness refers to connectedness between the objects in an image. Object-based (OB) connectedness refers to connectedness between the interpreted objects. In Experiment 1, a monocular depth cue (shadow) was used to distinguish different relation types between object pairs. Three relation types were created: IB/OB-connected objects, IB/OB-disconnected objects, and IB-connected/OB-disconnected objects. It was found that IB/OB-connected objects were matched faster than IB/OB-disconnected objects. Objects that were IB-connected/OB-disconnected were matched equally to IB/OB-disconnected objects. In Experiment 2, stereoscopic presentation was used. With relation types comparable to those in Experiment 1, it was again found that OB connectedness determined speed of matching, rather than IB connectedness. We conclude that matching of projections of three-dimensional objects depends more on OB connectedness than on IB connectedness.
Depression, anxiety and anger in subtypes of irritable bowel syndrome patients.
Muscatello, Maria Rosaria A; Bruno, Antonio; Pandolfo, Gianluca; Micò, Umberto; Stilo, Simona; Scaffidi, Mariagrazia; Consolo, Pierluigi; Tortora, Andrea; Pallio, Socrate; Giacobbe, Giuseppa; Familiari, Luigi; Zoccali, Rocco
2010-03-01
The present study aimed to elucidate the differences in depression, anxiety, anger, and quality of life in a sample of non-psychiatric IBS patients, starting from the hypothesis that IBS subtypes may have different symptomatic expressions of negative emotions with different outcomes on quality of life measures. Forty-two constipation-predominant IBS (C-IBS) subjects and 44 diarrhea-predominant IBS (D-IBS) subjects, after an examination by a gastroenterologist and a total colonoscopy, underwent a clinical interview and psychometric examination for the assessment of depression, anxiety, anger and quality of life. IBS subtypes showed different symptomatic profiles in depression, anxiety and anger, with C-IBS patients more psychologically distressed than D-IBS subjects. Affective and emotional symptoms should be considered as specific and integral to the syndrome, and recognizing the differences between IBS subtypes may have relevant implications for treatment options and clinical outcome.
A Swedish national adoption study of risk of irritable bowel syndrome (IBS)
Waehrens, Rasmus; Sundquist, Jan; Sundquist, Kristina; Pirouzifard, MirNabi
2017-01-01
Objectives Irritable bowel syndrome (IBS) clusters in families, but the familial risk of IBS has not been determined in adoptees. Studying adoptees and their biological and adoptive parents is a strong study design for separating genetic from environmental causes of familial clustering. This nationwide study aimed to separate the biological (genetic) and familial environmental contribution to the familial transmission of IBS. Methods We performed a family study for Swedish-born adoptees born from 1951 until 1995, and their biological and adoptive parents. The Swedish Multigeneration Register was linked to the Hospital Register (inpatients and outpatients) for the period 1964–2012 and the Swedish Outpatient Care Register for 2001–2012, and the Swedish Primary Healthcare register for 1989–2012. ORs for IBS were calculated for adoptees with an affected biological parent with IBS compared with adoptees without a biological parent with IBS. The OR for IBS was also determined in adoptees with an adoptive parent with IBS compared with adoptees without an adoptive parent with IBS. Heritability h 2 (±SE) was also determined. Results The ORs for IBS were 1.67 in adoptees (95% CI 1.06 to 2.62) of biological parents diagnosed with IBS. The ORs for IBS were 0.88 in adoptees (95% CI 0.48 to 1.63) of adoptive parents diagnosed with IBS. The heritability was 19.5%±8.5%. Conclusions The present study indicates that biological (genetic) factors are important for the familial clustering of IBS. The heritability calculated is in the range from twin studies and suggests that heritability may be estimated in adoptees. PMID:29119001
A Swedish national adoption study of risk of irritable bowel syndrome (IBS).
Waehrens, Rasmus; Zöller, Bengt; Sundquist, Jan; Sundquist, Kristina; Pirouzifard, MirNabi
2017-01-01
Irritable bowel syndrome (IBS) clusters in families, but the familial risk of IBS has not been determined in adoptees. Studying adoptees and their biological and adoptive parents is a strong study design for separating genetic from environmental causes of familial clustering. This nationwide study aimed to separate the biological (genetic) and familial environmental contribution to the familial transmission of IBS. We performed a family study for Swedish-born adoptees born from 1951 until 1995, and their biological and adoptive parents. The Swedish Multigeneration Register was linked to the Hospital Register (inpatients and outpatients) for the period 1964-2012 and the Swedish Outpatient Care Register for 2001-2012, and the Swedish Primary Healthcare register for 1989-2012. ORs for IBS were calculated for adoptees with an affected biological parent with IBS compared with adoptees without a biological parent with IBS. The OR for IBS was also determined in adoptees with an adoptive parent with IBS compared with adoptees without an adoptive parent with IBS. Heritability h 2 (±SE) was also determined. The ORs for IBS were 1.67 in adoptees (95% CI 1.06 to 2.62) of biological parents diagnosed with IBS. The ORs for IBS were 0.88 in adoptees (95% CI 0.48 to 1.63) of adoptive parents diagnosed with IBS. The heritability was 19.5%±8.5%. The present study indicates that biological (genetic) factors are important for the familial clustering of IBS. The heritability calculated is in the range from twin studies and suggests that heritability may be estimated in adoptees.
45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation \\1\\
Code of Federal Regulations, 2010 CFR
2000-10-01
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45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1
Code of Federal Regulations, 2010 CFR
2002-10-01
... 45 Public Welfare 1 2002-10-01 2002-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare GENERAL ADMINISTRATION... FINANCIAL ASSISTANCE Procedures [Interim] Interim procedures. Pt. 86, Index Subject Index to Title IX...
45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation \\1\\
Code of Federal Regulations, 2010 CFR
1999-10-01
... 45 Public Welfare 1 1999-10-01 1999-10-01 false Subject Index to Title IX Preamble and Regulation \\1\\ Index Subject Index to Title IX Preamble and Regulation \\1\\ Public Welfare DEPARTMENT OF... procedures. Pt. 86, Index Subject Index to Title IX Preamble and Regulation \\1\\ 1 Preamble paragraph numbers...
Mujagic, Z; Ludidi, S; Keszthelyi, D; Hesselink, M A M; Kruimel, J W; Lenaerts, K; Hanssen, N M J; Conchillo, J M; Jonkers, D M A E; Masclee, A A M
2014-08-01
Intestinal permeability has been studied in small groups of IBS patients with contrasting findings. To assess intestinal permeability at different sites of the GI tract in different subtypes of well-characterised IBS patients and healthy controls (HC), and to assess potential confounding factors. IBS patients and HC underwent a multi-sugar test to assess site-specific intestinal permeability. Sucrose excretion and lactulose/rhamnose ratio in 0-5 h urine indicated gastroduodenal and small intestinal permeability, respectively. Sucralose/erythritol ratio in 0-24 h and 5-24 h urine indicated whole gut and colonic permeability, respectively. Linear regression analysis was used to assess the association between IBS groups and intestinal permeability and to adjust for age, sex, BMI, anxiety or depression, smoking, alcohol intake and use of medication. Ninety-one IBS patients, i.e. 37% IBS-D, 23% IBS-C, 33% IBS-M and 7% IBS-U and 94 HC were enrolled. Urinary sucrose excretion was significantly increased in the total IBS group [μmol, median (Q1;Q3): 5.26 (1.82;11.03) vs. 2.44 (0.91;5.85), P < 0.05], as well as in IBS-C and IBS-D vs. HC. However, differences attenuated when adjusting for confounders. The lactulose/rhamnose ratio was increased in IBS-D vs. HC [0.023 (0.013;0.038) vs. 0.014 (0.008;0.025), P < 0.05], which remained significant after adjustment for confounders. No difference was found in 0-24 and 5-24 h sucralose/erythritol ratio between groups. Small intestinal permeability is increased in patients with IBS-D compared to healthy controls, irrespective of confounding factors. Adjustment for confounders is necessary when studying intestinal permeability, especially in a heterogeneous disorder such as IBS. © 2014 John Wiley & Sons Ltd.
Liu, Z J; Wei, H; Duan, L P; Zhu, S W; Zhang, L; Wang, K
2016-06-28
To investigate the prevalence and clinical features of small intestinal bacterial overgrowth (SIBO) in diarrhea-predominant irritable bowel syndrome (IBS-D) patients detected by hydrogen and methane in lactulose breath test (LBT), and to study the effects of rifaximin in IBS-D patients. Consecutive patients with IBS-D who met Rome Ⅲ criteria, and gender- and age-matched healthy volunteers were enrolled from March 2015 to January 2016 in Peking University Third Hospital. All the ISB-D patients underwent LBT to detect the prevalence of SIBO. The clinical and LBT features of IBS with SIBO (IBS-P group) and without SIBO (IBS-N group) were analyzed. The effects of rifaximin therapy (0.4 g, twice per day for 4 weeks) in IBS-D patients were evaluated by comparing changes in clinical features and LBT results after treatment. (1) Eighty-four IBS-D patients and 22 healthy controls were enrolled. The prevalence of SIBO in IBS-D patients was 41.67% (35/84), with 27 (77.14%) only hydrogen-positive, 5 (14.29%) methane-positive, and 3 (8.57%) both methane- and hydrogen-positive. (2) The body mass index (BMI) in the IBS-P group was lower than in the IBS-N group [(21.61±0.57) vs (23.44±0.54) kg/m(2,) P<0.05], the maximum stool frequency was also less than in the IBS-N group [(3.85±0.23) vs (4.88±0.35) times/day, P<0.05]. (3) No significant difference was found in oro-cecal transit time (OCTT) among IBS-P, IBS-N and healthy controls. The hydrogen concentration in small intestinal and colonic sections in breath of the IBS-P group was higher than that of both healthy controls and the IBS-N group, while methane concentration in small intestinal and colonic sections (160 min) was higher than that of the IBS-N group (all P<0.05). (4) There was no linear relationship between mean hydrogen and methane concentrations in LBT among the IBS-P, the IBS-N and healthy control groups (all r<0.35, P>0.05). (5) Totally 13 IBS-P patients received rifaximin therapy, in whom the symptoms of abdomen pain, bloating, fecal consistency, stool frequency, and stool satisfactory were significantly improved after treatment (all P<0.05); 8 IBS-N patients received rifaximin therapy, in whom fecal consistency, stool frequency, and satisfactory were significantly improved (all P<0.05). (6) And 5/13 of the IBS-P patients receiving rifaximin presented negative LBT results after rifaximin therapy, with lower hydrogen concentration at all the time points, especially in colonic section (120 min) [(34.54±7.32) ×10(-6) vs (52.23±9.40) ×10(-6,) P<0.05] and lower methane concentration especially in small intestinal section (80 min) [(8.54±0.95) ×10(-6) vs (11.31±0.94) ×10(-6,) P<0.05]. About 41.67% of the IBS-D patients meeting Rome Ⅲ criteria have SIBO, which can be better screened by combining hydrogen and methane in LBT compared with only hydrogen in LBT. SIBO can affect nutritional status in IBS-D patients. Rifaximin can improve the systematic symptoms of IBS-D patients with SIBO, also reduce hydrogen and methane concentration in breath, while only improving diarrhea in IBS-D patients without SIBO. Some differences in gut microbiota may exist between IBS-D with and without SIBO.
Okami, Yukiko; Kato, Takako; Nin, Gyozen; Harada, Kiyomi; Aoi, Wataru; Wada, Sayori; Higashi, Akane; Okuyama, Yusuke; Takakuwa, Susumu; Ichikawa, Hiroshi; Kanazawa, Motoyori; Fukudo, Shin
2011-12-01
Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder comprising abdominal pain, abdominal discomfort, and disordered defecation. The prevalence of IBS is 10-15% in the general population. This study investigated the prevalence of IBS and the relationship between IBS and stress, lifestyle, and dietary habits among nursing and medical school students. A blank self-administrated questionnaire was used to survey 2,639 students studying nursing or medicine. This questionnaire asked about IBS symptoms, lifestyle, dietary intake, life events, anxiety, and depression. The questionnaires were collected from 2,365 students (89.6%) and the responses of 1,768 students (74.8%) were analyzed. The prevalence of IBS was 35.5% as a whole, 25.2% in males and 41.5% in females. Significantly higher stress scores (anxiety and depression) and life events were found in the IBS group than in the non-IBS group. Sleep disorders and the time spent sitting were also higher in males with IBS. In the IBS group, females ate less fish, fruit, milk, and green-yellow vegetables, and more processed food products than the non-IBS group (p = 0.001, p = 0.002, p = 0.032, p = 0.037, p < 0.001). The rates of missed meals and irregular mealtimes were significantly higher in females in the IBS group (p = 0.001, p = 0.013). The prevalence of IBS was higher among nursing and medical students, and further interventional studies are needed to improve IBS symptoms.
Lacy, B E
2016-01-01
Irritable bowel syndrome (IBS) is the most common functional gastrointestinal disorder worldwide. The global prevalence of IBS is estimated to be as high as 15%. For many patients, IBS is a chronic disorder which can significantly reduce quality of life. Just as important as the effects on any one individual, IBS also places a significant impact on the population as a whole with its negative effects on the health care system. Irritable bowel syndrome is categorized into one of three main categories: IBS with diarrhea, IBS with constipation, and IBS with mixed bowel habits. Patients with diarrhea-predominant IBS (IBS-D) comprise a substantial proportion of the overall IBS population. A number of therapeutic options exist to treat the symptoms of abdominal pain, bloating, diarrhea, and fecal urgency, including non-pharmacologic therapies such as dietary changes and probiotics, or pharmacologic therapies such as loperamide and alosetron. However, many patients have persistent symptoms despite these therapies. This unmet need led to the development of eluxadoline, a mu-opioid receptor agonist/delta-opioid receptor antagonist/kappa-receptor agonist. Approved by the FDA in May 2015, this medication shows promise in the treatment of diarrhea-predominant IBS for both men and women. This monograph will briefly review the impact of IBS, discuss current treatments for IBS-D, and then focus on the pharmacology, clinical efficacy and safety of eluxadoline. Potential mechanisms related to rare events of acute pancreatitis or elevated liver tests will be discussed. © 2015 John Wiley & Sons Ltd.
Palasuberniam, Pratheeba; Yang, Xue; Kraus, Daniel; Jones, Patrick; Myers, Kenneth A; Chen, Bin
2015-08-18
Photosensitizer protoporphyrin IX (PpIX) fluorescence, intracellular localization and cell response to photodynamic therapy (PDT) were analyzed in MCF10A normal breast epithelial cells and a panel of human breast cancer cells including estrogen receptor (ER) positive, human epidermal growth factor receptor 2 (HER2) positive and triple negative breast cancer (TNBC) cells after treatment with PpIX precursor aminolevulinic acid (ALA). Although PpIX fluorescence was heterogeneous in different cells, TNBC cells showed significantly lower PpIX level than MCF10A and ER- or HER2-positive cells. PpIX fluorescence in TNBC cells also had much less mitochondrial localization than other cells. There was an inverse correlation between PpIX fluorescence and cell viability after PDT. Breast cancer cells with the highest PpIX fluorescence were the most sensitive to ALA-PDT and TNBC cells with the lowest PpIX level were resistant to PDT. Treatment of TNBC cells with ABCG2 transporter inhibitor Ko143 significantly increased ALA-PpIX fluorescence, enhanced PpIX mitochondrial accumulation and sensitized cancer cells to ALA-PDT. Ko143 treatment had little effect on PpIX production and ALA-PDT in normal and ER- or HER2-positive cells. These results demonstrate that enhanced ABCG2 activity renders TNBC cell resistance to ALA-PDT and inhibiting ABCG2 transporter is a promising approach for targeting TNBC with ALA-based modality.
Improving Search Properties in Genetic Programming
NASA Technical Reports Server (NTRS)
Janikow, Cezary Z.; DeWeese, Scott
1997-01-01
With the advancing computer processing capabilities, practical computer applications are mostly limited by the amount of human programming required to accomplish a specific task. This necessary human participation creates many problems, such as dramatically increased cost. To alleviate the problem, computers must become more autonomous. In other words, computers must be capable to program/reprogram themselves to adapt to changing environments/tasks/demands/domains. Evolutionary computation offers potential means, but it must be advanced beyond its current practical limitations. Evolutionary algorithms model nature. They maintain a population of structures representing potential solutions to the problem at hand. These structures undergo a simulated evolution by means of mutation, crossover, and a Darwinian selective pressure. Genetic programming (GP) is the most promising example of an evolutionary algorithm. In GP, the structures that evolve are trees, which is a dramatic departure from previously used representations such as strings in genetic algorithms. The space of potential trees is defined by means of their elements: functions, which label internal nodes, and terminals, which label leaves. By attaching semantic interpretation to those elements, trees can be interpreted as computer programs (given an interpreter), evolved architectures, etc. JSC has begun exploring GP as a potential tool for its long-term project on evolving dextrous robotic capabilities. Last year we identified representation redundancies as the primary source of inefficiency in GP. Subsequently, we proposed a method to use problem constraints to reduce those redundancies, effectively reducing GP complexity. This method was implemented afterwards at the University of Missouri. This summer, we have evaluated the payoff from using problem constraints to reduce search complexity on two classes of problems: learning boolean functions and solving the forward kinematics problem. We have also developed and implemented methods to use additional problem heuristics to fine-tune the searchable space, and to use typing information to further reduce the search space. Additional improvements have been proposed, but they are yet to be explored and implemented.
Kanazawa, Motoyori; Miwa, Hiroto; Nakagawa, Ayako; Kosako, Masanori; Akiho, Hiraku; Fukudo, Shin
2016-01-01
Abdominal bloating is a common symptom in patients with irritable bowel syndrome with constipation (IBS-C). However, it is not included among the required items in the Rome III diagnostic criteria for IBS. Little is known about an impact of abdominal bloating seen in patients with IBS-C. Using a large population-based sample, the aim of the present study was to investigate what is the most bothersome symptom in subjects with IBS-C. An Internet survey of 30,000 adults drawn from the general public throughout Japan was conducted to identify subtypes of IBS using the Rome III diagnostic questionnaire. Consecutively, the screened subjects with IBS-C and the same number of age- and sex-matched non-IBS subjects who were randomly selected as controls were asked to answer a questionnaire on the degree of anxiety they experienced in their daily lives, thoughts about bowel habit, and their dominant gastrointestinal symptoms together with exacerbation factors (for IBS-C only). The screening survey showed that the prevalence of overall IBS was 16.5 % (female 17.4 %, male 15.5 %) and that 2.8 % met the criteria for IBS-C, 4.5 % for IBS with diarrhea (IBS-D) and 8.2 % for mixed IBS (IBS-M). Seven hundred and fifty-nine of 835 (90.9 %) subjects with IBS-C and 746 of 830 (89.9 %) control subjects completed the consecutive questionnaire. IBS-C subjects felt a higher degree of anxiety in their daily lives (p < 0.01) and considered bowel habit to be an indicator of health (p < 0.01) to a greater extent than control subjects. In IBS-C, the degree of anxiety was significantly associated with abdominal discomfort (p < 0.01), pain (p < 0.01) and bloating (p = 0.02), but not with the frequency of bowel habit (p > 0.1). Abdominal bloating was the most bothersome symptom (27.5 %), which was more likely to occur after a meal (52.2 %), at work/school (29.2 %) and during times of stress (26.8 %). Only 4.5 % of IBS-C subjects reported abdominal pain as the 'most bothersome' symptom. A large population-based Internet survey suggests that abdominal bloating has a great impact on the daily lives of subjects diagnosed with IBS-C. Not only bowel movement/abdominal pain but also abdominal bloating should be evaluated in patients with IBS-C.
Cloning and functional characterization of the guinea pig apoptosis inhibitor protein Survivin.
Habtemichael, Negusse; Wünsch, Desiree; Bier, Carolin; Tillmann, Sarah; Unruhe, Britta; Frauenknecht, Katrin; Heinrich, Ulf-Rüdiger; Mann, Wolf J; Stauber, Roland H; Knauer, Shirley K
2010-12-01
The guinea pig is widely used as a model to study (patho)physiological processes, such as neurodegenerative disorders. Survivin's dual function as an apoptosis inhibitor and a mitotic regulator is crucial not only for ordered development but its modulation seems crucial also under disease conditions. However, data on the expression and function of the guinea pig Survivin protein (Survivin(Gp)) are currently lacking. Here, we here report the cloning and functional characterization of Survivin(Gp). The respective cDNA was cloned from spleen mRNA, containing a 426 bp open reading frame encoding for a protein of 142aa. Survivin(Gp) displays a high homology to the human and murine orthologue, especially in domains critical for function, such as binding sites for chromosomal passenger complex (CPC) proteins and the nuclear export signal (NES). Notably, phylogenetic analyses revealed that Survivin(Gp) is more related to humans than to rodents. Ectopic expression studies of a Survivin(Gp)-GFP fusion confirmed its dynamic intracellular localization, analogous to the human and murine counterparts. In interphase cells, Survivin(Gp)-GFP was predominantly cytoplasmic and accumulated in the nucleus following export inhibition with leptomycin B (LMB). A typical CPC protein localization during mitosis was observed for Survivin(Gp)-GFP. Microinjection experiments together with genetic knockout demonstrated that the NES is essential for the anti-apoptotic and regulatory role of Survivin(Gp) during cell division. In vivo protein interaction assays further demonstrated its dimerization with human Survivin and its interaction with human CPC proteins. Importantly, RNAi-depletion studies show that Survivin(Gp) can fully substitute for human Survivin as an apoptosis inhibitor and a mitotic effector. Immunohistochemistry, immunofluorescence, and western blotting were employed to detect Survivin expression in guinea pig tissues. Besides its expression in proliferating tissues, such as spleen and liver, we also found Survivin in terminally differentiated cell types. Importantly, Survivin was detectable also in the cochlea, suggesting a potential role for Survivin in the auditory system. We provide the first experimental evidence for the expression of Survivin in the guinea pig. As Survivin(Gp) can substitute for known functions of human Survivin, the guinea pig model will now also allow investigating Survivin's (patho)physiological role and to test Survivin-directed potential therapeutic strategies. Copyright © 2010 Elsevier B.V. All rights reserved.
Post-infectious IBS, tropical sprue and small intestinal bacterial overgrowth: the missing link.
Ghoshal, Uday C; Gwee, Kok-Ann
2017-07-01
Evidence is emerging that IBS, a hitherto enigmatic disorder thought to be predominantly related to psychological factors, has a microorganic basis in a subset of patients with the disease. Post-infectious IBS (PI-IBS), commonly of the diarrhoea-predominant subtype (defined as new development of IBS following acute infectious diarrhoea), is one such condition known to occur in up to 10-30% individuals after acute gastroenteritis. However, following acute infectious gastroenteritis, patients can also develop post-infectious malabsorption syndrome (PI-MAS), popularly known as tropical sprue. As no study on PI-IBS has rigorously excluded tropical sprue by appropriate investigations, including small intestinal biopsy, the frequency of tropical sprue among patients with PI-IBS is not known. Small intestinal bacterial overgrowth (SIBO) has been suggested to be associated with IBS in general, and in particular diarrhoea-predominant IBS, including PI-IBS. SIBO is also known to be associated with tropical sprue. As both IBS, particularly the subset probably associated with SIBO, and tropical sprue improve with antibiotic treatment, we provide evidence and an explanatory model to support a link among these disorders.
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2011-07-01
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2011-10-01
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45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1
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2003-10-01
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34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1
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2009-07-01
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2015-07-01
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34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1
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2003-07-01
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45 CFR Subject Index to Title IX... - Subject Index to Title IX Preamble and Regulation 1
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2006-10-01
... 45 Public Welfare 1 2006-10-01 2006-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare DEPARTMENT OF HEALTHAND... Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in brackets [ ]. A...
34 CFR Subject Index to Title IX... - Subject Index to Title IX Preamble and Regulation 1
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2016-07-01
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34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1
Code of Federal Regulations, 2010 CFR
2007-07-01
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34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1
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2004-07-01
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45 CFR Subject Index to Title IX... - Subject Index to Title IX Preamble and Regulation 1
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2016-10-01
... 45 Public Welfare 1 2016-10-01 2016-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare Department of Health and... Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in brackets [ ]. A...
34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1
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2012-07-01
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45 CFR Subject Index to Title IX... - Subject Index to Title IX Preamble and Regulation 1
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2017-10-01
... 45 Public Welfare 1 2017-10-01 2017-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare Department of Health and... Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in brackets [ ]. A...