Genome-Wide Association Studies Identify Heavy Metal ATPase3 as the Primary Determinant of Natural Variation in Leaf Cadmium in Arabidopsis thaliana

PubMed Central

Chao, Dai-Yin; Silva, Adriano; Baxter, Ivan; Huang, Yu S.; Nordborg, Magnus; Danku, John; Lahner, Brett; Yakubova, Elena; Salt, David E.

2012-01-01

Understanding the mechanism of cadmium (Cd) accumulation in plants is important to help reduce its potential toxicity to both plants and humans through dietary and environmental exposure. Here, we report on a study to uncover the genetic basis underlying natural variation in Cd accumulation in a world-wide collection of 349 wild collected Arabidopsis thaliana accessions. We identified a 4-fold variation (0.5–2 µg Cd g−1 dry weight) in leaf Cd accumulation when these accessions were grown in a controlled common garden. By combining genome-wide association mapping, linkage mapping in an experimental F2 population, and transgenic complementation, we reveal that HMA3 is the sole major locus responsible for the variation in leaf Cd accumulation we observe in this diverse population of A. thaliana accessions. Analysis of the predicted amino acid sequence of HMA3 from 149 A. thaliana accessions reveals the existence of 10 major natural protein haplotypes. Association of these haplotypes with leaf Cd accumulation and genetics complementation experiments indicate that 5 of these haplotypes are active and 5 are inactive, and that elevated leaf Cd accumulation is associated with the reduced function of HMA3 caused by a nonsense mutation and polymorphisms that change two specific amino acids. PMID:22969436

Perivascular Epithelioid Cell Tumor (PEComa) of Pancreas Diagnosed Preoperatively by Endoscopic Ultrasound-Guided Fine-Needle Aspiration: A Case Report and Review of Literature.

PubMed

Collins, Katrina; Buckley, Tinera; Anderson, Kevin; Karasik, Michael; Ligato, Saverio

2017-01-01

Perivascular epithelioid cell tumors (PEComas) of the pancreas are extremely rare mesenchymal tumors and to our knowledge, only 17 cases have been reported in the English literature to date. We report our experience with a new case of primary pancreatic PEComa diagnosed preoperatively by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) complemented by tissue cell block and immunohistochemistry. The patient was a 54-year-old female whose chief complaint was intermittent severe right upper quadrant abdominal pain. Computed-tomography (CT) imaging revealed a mass between the head and the body of the pancreas. EUS-FNA smear preparation was obtained but was nondiagnostic. However, examination of the tissue cell block showed sheets of epithelioid cells with abundant eosinophilic cytoplasm and immunohistochemistry studies revealed positivity for both melanocytic (HMB-45 and Melan-A) and smooth muscle markers (actin and desmin). A diagnosis of PEComa was made and an uncomplicated middle pancreatectomy was performed. Our case and review of the literature demonstrates that EUS-FNA complemented with tissue cell block increases cellular yield, improved preoperative diagnostic accuracy, and may assist the surgeon in planning conservative surgical management. Diagn. Cytopathol. 2017;45:59-65. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

The Manuscript That We Finished: Structural Separation Reduces the Cost of Complement Coercion

ERIC Educational Resources Information Center

Lowder, Matthew W.; Gordon, Peter C.

2015-01-01

Two eye-tracking experiments examined the effects of sentence structure on the processing of complement coercion, in which an event-selecting verb combines with a complement that represents an entity (e.g., "began the memo"). Previous work has demonstrated that these expressions impose a processing cost, which has been attributed to the…

Heterologous Expression of sahH Reveals That Biofilm Formation Is Autoinducer-2-independent in Streptococcus sanguinis but Is Associated with an Intact Activated Methionine Cycle*

PubMed Central

Redanz, Sylvio; Standar, Kerstin; Podbielski, Andreas; Kreikemeyer, Bernd

2012-01-01

Numerous studies have claimed deleterious effects of LuxS mutation on many bacterial phenotypes, including bacterial biofilm formation. Genetic complementation mostly restored the observed mutant phenotypes to WT levels, leading to the postulation that quorum sensing via a family of molecules generically termed autoinducer-2 (AI-2) is essential for many phenotypes. Because LuxS mutation has dual effects, this hypothesis needs to be investigated into the details for each bacterial species. In this study we used S. sanguinis SK36 as a model biofilm bacterium and employed physiological characterization and transcriptome approaches on WT and luxS-deficient strains, in combination with chemical, luxS, and sahH complementation experiments. SahH enables a direct conversion of SAH to homocysteine and thereby restores the activated methionine cycle in a luxS-negative background without formation of the AI-2 precursor 4,5-dihydroxy-2,3-pentanedione. With this strategy we were able to dissect the individual contribution of LuxS and AI-2 activity in detail. Our data revealed that S. sanguinis biofilm formation is independent from AI-2 substance pools and is rather supported by an intact activated methyl cycle. Of 216 differentially transcribed genes in the luxS mutant, 209 were restored by complementation with a gene encoding the S-adenosylhomocysteine hydrolase. Only nine genes, mainly involved in natural competence, were directly affected by the AI-2 quorum-sensing substance pool. Cumulatively, this suggested that biofilm formation in S. sanguinis is not under control of AI-2. Our study suggests that previously evaluated LuxS mutants in other species need to be revisited to resolve the precise contribution of AI-2 substance pools and the methionine pathways. PMID:22942290

Novel Evasion Mechanisms of the Classical Complement Pathway

PubMed Central

Garcia, Brandon L.; Zwarthoff, Seline A.; Rooijakkers, Suzan H. M.; Geisbrecht, Brian V.

2016-01-01

Complement is a network of soluble and cell surface-associated proteins which gives rise to a self-amplifying, yet tightly regulated system with fundamental roles in immune surveillance and clearance. Complement becomes activated on the surface of ‘non-self’ cells by one of three initiating mechanisms known as the classical, lectin, or alternative pathways. Evasion of complement function is a hallmark of invasive pathogens and hematophagous organisms. While many complement inhibition strategies hinge on hijacking activities of endogenous complement regulatory proteins, an increasing number of uniquely evolved evasion molecules have been discovered over the past decade. In this review we focus on several recent investigations which have revealed mechanistically distinct inhibitors of the classical pathway. Because the classical pathway is an important and specific mediator of various autoimmune and inflammatory disorders, in-depth knowledge of novel evasion mechanisms could direct future development of therapeutic anti-inflammatory molecules. PMID:27591336

Novel Evasion Mechanisms of the Classical Complement Pathway.

PubMed

Garcia, Brandon L; Zwarthoff, Seline A; Rooijakkers, Suzan H M; Geisbrecht, Brian V

2016-09-15

Complement is a network of soluble and cell surface-associated proteins that gives rise to a self-amplifying, yet tightly regulated system with fundamental roles in immune surveillance and clearance. Complement becomes activated on the surface of nonself cells by one of three initiating mechanisms known as the classical, lectin, and alternative pathways. Evasion of complement function is a hallmark of invasive pathogens and hematophagous organisms. Although many complement-inhibition strategies hinge on hijacking activities of endogenous complement regulatory proteins, an increasing number of uniquely evolved evasion molecules have been discovered over the past decade. In this review, we focus on several recent investigations that revealed mechanistically distinct inhibitors of the classical pathway. Because the classical pathway is an important and specific mediator of various autoimmune and inflammatory disorders, in-depth knowledge of novel evasion mechanisms could direct future development of therapeutic anti-inflammatory molecules. Copyright © 2016 by The American Association of Immunologists, Inc.

Complementing the Australian Primary School Health and Physical Education (HPE) Curriculum: Exploring Children's HPE Learning Experiences within Varying School Ground Equipment Contexts

ERIC Educational Resources Information Center

Hyndman, Brendon; Mahony, Linda; Te Ava, Aue; Smith, Sue; Nutton, Georgie

2017-01-01

This paper unearths how primary school children experience and can complement the Australian HPE curriculum within three unique school ground equipment scenarios that include an "empty", "loose parts" and a "traditional" school ground context. Using direct observation, 490 scans were undertaken of the school grounds…

Complement activation promotes colitis-associated carcinogenesis through activating intestinal IL-1β/IL-17A axis.

PubMed

Ning, C; Li, Y-Y; Wang, Y; Han, G-C; Wang, R-X; Xiao, H; Li, X-Y; Hou, C-M; Ma, Y-F; Sheng, D-S; Shen, B-F; Feng, J-N; Guo, R-F; Li, Y; Chen, G-J

2015-11-01

Colitis-associated colorectal cancer (CAC) is the most serious complication of inflammatory bowel disease (IBD). Excessive complement activation has been shown to be involved in the pathogenesis of IBD. However, its role in the development of CAC is largely unknown. Here, using a CAC model induced by combined administration of azoxymethane (AOM) and dextran sulfate sodium (DSS), we demonstrated that complement activation was required for CAC pathogenesis. Deficiency in key components of complement (e.g., C3, C5, or C5a receptor) rendered tumor repression in mice subjected to AOM/DSS. Mechanistic investigation revealed that complement ablation dramatically reduced proinflammatory cytokine interleukin (IL)-1β levels in the colonic tissues that was mainly produced by infiltrating neutrophils. IL-1β promoted colon carcinogenesis by eliciting IL-17 response in intestinal myeloid cells. Furthermore, complement-activation product C5a represented a potent inducer for IL-1β in neutrophil, accounting for downregulation of IL-1β levels in the employed complement-deficient mice. Overall, our study proposes a protumorigenic role of complement in inflammation-related colorectal cancer and that the therapeutic strategies targeting complement may be beneficial for the treatment of CAC in clinic.

Eye-Tracking and Corpus-Based Analyses of Syntax-Semantics Interactions in Complement Coercion

PubMed Central

Lowder, Matthew W.; Gordon, Peter C.

2016-01-01

Previous work has shown that the difficulty associated with processing complex semantic expressions is reduced when the critical constituents appear in separate clauses as opposed to when they appear together in the same clause. We investigated this effect further, focusing in particular on complement coercion, in which an event-selecting verb (e.g., began) combines with a complement that represents an entity (e.g., began the memo). Experiment 1 compared reading times for coercion versus control expressions when the critical verb and complement appeared together in a subject-extracted relative clause (SRC) (e.g., The secretary that began/wrote the memo) compared to when they appeared together in a simple sentence. Readers spent more time processing coercion expressions than control expressions, replicating the typical coercion cost. In addition, readers spent less time processing the verb and complement in SRCs than in simple sentences; however, the magnitude of the coercion cost did not depend on sentence structure. In contrast, Experiment 2 showed that the coercion cost was reduced when the complement appeared as the head of an object-extracted relative clause (ORC) (e.g., The memo that the secretary began/wrote) compared to when the constituents appeared together in an SRC. Consistent with the eye-tracking results of Experiment 2, a corpus analysis showed that expressions requiring complement coercion are more frequent when the constituents are separated by the clause boundary of an ORC compared to when they are embedded together within an SRC. The results provide important information about the types of structural configurations that contribute to reduced difficulty with complex semantic expressions, as well as how these processing patterns are reflected in naturally occurring language. PMID:28529960

Plasma-based proteomics reveals immune response, complement and coagulation cascades pathway shifts in heat-stressed lactating dairy cows.

PubMed

Min, Li; Cheng, Jianbo; Zhao, Shengguo; Tian, He; Zhang, Yangdong; Li, Songli; Yang, Hongjian; Zheng, Nan; Wang, Jiaqi

2016-09-02

Heat stress (HS) has an enormous economic impact on the dairy industry. In recent years, many researchers have investigated changes in the gene expression and metabolomics profiles in dairy cows caused by HS. However, the proteomics profiles of heat-stressed dairy cows have not yet been completely elucidated. We compared plasma proteomics from HS-free and heat-stressed dairy cows using an iTRAQ labeling approach. After the depletion of high abundant proteins in the plasma, 1472 proteins were identified. Of these, 85 proteins were differentially abundant in cows exposed to HS relative to HS-free. Database searches combined with GO and KEGG pathway enrichment analyses revealed that many components of the complement and coagulation cascades were altered in heat-stressed cows compared with HS-free cows. Of these, many factors in the complement system (including complement components C1, C3, C5, C6, C7, C8, and C9, complement factor B, and factor H) were down-regulated by HS, while components of the coagulation system (including coagulation factors, vitamin K-dependent proteins, and fibrinogens) were up-regulated by HS. In conclusion, our results indicate that HS decreases plasma levels of complement system proteins, suggesting that immune function is impaired in dairy cows exposed to HS. Though many aspects of heat stress (HS) have been extensively researched, relatively little is known about the proteomics profile changes that occur during heat exposure. In this work, we employed a proteomics approach to investigate differential abundance of plasma proteins in HS-free and heat-stressed dairy cows. Database searches combined with GO and KEGG pathway enrichment analyses revealed that HS resulted in a decrease in complement components, suggesting that heat-stressed dairy cows have impaired immune function. In addition, through integrative analyses of proteomics and previous metabolomics, we showed enhanced glycolysis, lipid metabolic pathway shifts, and nitrogen repartitioning in dairy cows exposed to HS. Our findings expand our current knowledge on the effects of HS on plasma proteomics in dairy cows and offer a new perspective for future research. Copyright © 2016 Elsevier B.V. All rights reserved.

Bioluminescent indicators for Ca2+ based on split Renilla luciferase complementation in living cells.

PubMed

Kaihara, Asami; Umezawa, Yoshio; Furukawa, Tetsushi

2008-01-01

Genetically encoded bioluminescent indicators for intracellular Ca2+ are described here with CaM-M13 interaction-induced complementation of split Renilla luciferase. The Ca2+-induced interaction between CaM and M13 leads to complementation of the N- and C-terminal halves of split Renilla luciferase in living cells. This intramolecular interaction results in the spontaneous and simultaneous emission of bioluminescence split Renilla luciferase. This is how intracellular Ca2+ is illuminated with the intramolecular complementation of split Renilla luciferase. The Ca2+-dependent spontaneous and simultaneous emission of bioluminescence promises to reveal Ca2+ dynamics in living cells, and also in vivo using the present indicators.

Complement therapeutics in inflammatory diseases: promising drug candidates for C3-targeted intervention.

PubMed

Mastellos, D C; Ricklin, D; Hajishengallis, E; Hajishengallis, G; Lambris, J D

2016-02-01

There is increasing appreciation that complement dysregulation lies at the heart of numerous immune-mediated and inflammatory disorders. Complement inhibitors are therefore being evaluated as new therapeutic options in various clinical translation programs and the first clinically approved complement-targeted drugs have profoundly impacted the management of certain complement-mediated diseases. Among the many members of the intricate protein network of complement, the central component C3 represents a 'hot-spot' for complement-targeted therapeutic intervention. C3 modulates both innate and adaptive immune responses and is linked to diverse immunomodulatory systems and biological processes that affect human pathophysiology. Compelling evidence from preclinical disease models has shown that C3 interception may offer multiple benefits over existing therapies or even reveal novel therapeutic avenues in disorders that are not commonly regarded as complement-driven, such as periodontal disease. Using the clinically developed compstatin family of C3 inhibitors and periodontitis as illustrative examples, this review highlights emerging therapeutic concepts and developments in the design of C3-targeted drug candidates as novel immunotherapeutics for oral and systemic inflammatory diseases. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Novel Scabies Mite Serpins Inhibit the Three Pathways of the Human Complement System

PubMed Central

Mika, Angela; Reynolds, Simone L.; Mohlin, Frida C.; Willis, Charlene; Swe, Pearl M.; Pickering, Darren A.; Halilovic, Vanja; Wijeyewickrema, Lakshmi C.; Pike, Robert N.; Blom, Anna M.; Kemp, David J.; Fischer, Katja

2012-01-01

Scabies is a parasitic infestation of the skin by the mite Sarcoptes scabiei that causes significant morbidity worldwide, in particular within socially disadvantaged populations. In order to identify mechanisms that enable the scabies mite to evade human immune defenses, we have studied molecules associated with proteolytic systems in the mite, including two novel scabies mite serine protease inhibitors (SMSs) of the serpin superfamily. Immunohistochemical studies revealed that within mite-infected human skin SMSB4 (54 kDa) and SMSB3 (47 kDa) were both localized in the mite gut and feces. Recombinant purified SMSB3 and SMSB4 did not inhibit mite serine and cysteine proteases, but did inhibit mammalian serine proteases, such as chymotrypsin, albeit inefficiently. Detailed functional analysis revealed that both serpins interfered with all three pathways of the human complement system at different stages of their activation. SMSB4 inhibited mostly the initial and progressing steps of the cascades, while SMSB3 showed the strongest effects at the C9 level in the terminal pathway. Additive effects of both serpins were shown at the C9 level in the lectin pathway. Both SMSs were able to interfere with complement factors without protease function. A range of binding assays showed direct binding between SMSB4 and seven complement proteins (C1, properdin, MBL, C4, C3, C6 and C8), while significant binding of SMSB3 occurred exclusively to complement factors without protease function (C4, C3, C8). Direct binding was observed between SMSB4 and the complement proteases C1s and C1r. However no complex formation was observed between either mite serpin and the complement serine proteases C1r, C1s, MASP-1, MASP-2 and MASP-3. No catalytic inhibition by either serpin was observed for any of these enzymes. In summary, the SMSs were acting at several levels mediating overall inhibition of the complement system and thus we propose that they may protect scabies mites from complement-mediated gut damage. PMID:22792350

Factor H-related proteins.

PubMed

Józsi, Mihály; Meri, Seppo

2014-01-01

Factor H-related proteins (CFHRs) are plasma glycoproteins related in structure and antigenicity to each other and to the complement inhibitory protein factor H. Such proteins are found in most mammals but their number and domain composition vary. This chapter summarizes our current knowledge on the human factor H-related proteins. In contrast to factor H, they have no strong complement inhibitory activity, although for some of them regulatory or complement modulatory activity has been reported. A common feature of CFHRs is that they bind to the C3b component of complement. Novel links between CFHRs and various diseases (C3 glomerulopathies, atypical hemolytic uremic syndrome and age-related macular degeneration) have been revealed in recent years, but we are still far from understanding their biological function.

A Novel fry1 Allele Reveals the Existence of a Mutant Phenotype Unrelated to 5′->3′ Exoribonuclease (XRN) Activities in Arabidopsis thaliana Roots

PubMed Central

Hirsch, Judith; Estavillo, Gonzalo M.; Javot, Hélène; Chiarenza, Serge; Mallory, Allison C.; Maizel, Alexis; Declerck, Marie; Pogson, Barry J.; Vaucheret, Hervé; Crespi, Martin; Desnos, Thierry; Thibaud, Marie-Christine; Nussaume, Laurent; Marin, Elena

2011-01-01

Background Mutations in the FRY1/SAL1 Arabidopsis locus are highly pleiotropic, affecting drought tolerance, leaf shape and root growth. FRY1 encodes a nucleotide phosphatase that in vitro has inositol polyphosphate 1-phosphatase and 3′,(2′),5′-bisphosphate nucleotide phosphatase activities. It is not clear which activity mediates each of the diverse biological functions of FRY1 in planta. Principal Findings A fry1 mutant was identified in a genetic screen for Arabidopsis mutants deregulated in the expression of Pi High affinity Transporter 1;4 (PHT1;4). Histological analysis revealed that, in roots, FRY1 expression was restricted to the stele and meristems. The fry1 mutant displayed an altered root architecture phenotype and an increased drought tolerance. All of the phenotypes analyzed were complemented with the AHL gene encoding a protein that converts 3′-polyadenosine 5′-phosphate (PAP) into AMP and Pi. PAP is known to inhibit exoribonucleases (XRN) in vitro. Accordingly, an xrn triple mutant with mutations in all three XRNs shared the fry1 drought tolerance and root architecture phenotypes. Interestingly these two traits were also complemented by grafting, revealing that drought tolerance was primarily conferred by the rosette and that the root architecture can be complemented by long-distance regulation derived from leaves. By contrast, PHT1 expression was not altered in xrn mutants or in grafting experiments. Thus, PHT1 up-regulation probably resulted from a local depletion of Pi in the fry1 stele. This hypothesis is supported by the identification of other genes modulated by Pi deficiency in the stele, which are found induced in a fry1 background. Conclusions/Significance Our results indicate that the 3′,(2′),5′-bisphosphate nucleotide phosphatase activity of FRY1 is involved in long-distance as well as local regulatory activities in roots. The local up-regulation of PHT1 genes transcription in roots likely results from local depletion of Pi and is independent of the XRNs. PMID:21304819

Clinical symptoms and DNA repair characteristics of xeroderma pigmentosum patients from Germany

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thielmann, H.W.; Popanda, O.; Edler, L.

1991-07-01

Sixty-one xeroderma pigmentosum (XP) patients living in the Federal Republic of Germany were investigated. Clinical symptoms were correlated with DNA repair parameters measured in fibroblasts grown from skin biopsies. Classification according to the international complementation groups revealed that of the 61 patients 3 belonged to group A, 26 to group C, 16 to group D, 3 to group E, and 2 to group F; 11 were of the XP variant type. A striking clinical aspect was the frequency of histogenetically different skin tumors varying from one XP complementation group to the other: squamous and basal cell carcinomas predominated in XPmore » group C; lentigo maligna melanomas were most frequent in group D; basal cell carcinomas occurred preferentially in group E and XP variants. Three DNA repair parameters were determined for 46 fibroblast strains: colony-forming ability (D0); DNA repair synthesis (G0); and DNA-incising capacity (E0). Dose-response experiments with up to 13 dose levels were performed throughout to achieve sufficient experimental accuracy. DNA-damaging treatments included UV light, the 'UV-like' carcinogen N-acetoxy-2-acetylaminofluorene, and the alkylating carcinogens methyl methanesulfonate and N-methyl-N-nitrosourea. Comparison of clinical signs and repair data was made on the basis of D0, G0, and E0 values of both individual cell strains and weighted means of XP complementation groups. Despite considerable clinical and biochemical heterogeneity within complementation groups distinctive features emerged. In general, D0, G0, and E0 values of all XP strains investigated, including XP variants, were found to be reduced upon treatment with UV light or N-acetoxy-2-acetylaminofluorene.« less

Symmetry and diffusivity of the interstitial hydrogen shallow-donor center in In 2O 3

DOE PAGES

Weiser, Philip; Qin, Ying; Yin, Weikai; ...

2016-11-16

Uniaxial stress experiments performed for the 3306 cm -1 vibrational line assigned to the interstitial-hydrogen, shallow-donor center in In 2O 3 reveal its symmetry and transition- moment direction. The defect alignment that can be produced by a [001] stress applied at 165 K is due to a process that is also a hydrogen- diffusion jump, providing a microscopic determination of the diffusion constant for H in In 2O 3 and its mechanism. Lastly, our experimental results strongly complement theoretical predictions for the structure and diffusion of the interstitial hydrogen donor center in In 2O 3.

Diagnosis of primary antibody and complement deficiencies in young adults after a first invasive bacterial infection.

PubMed

Sanges, S; Wallet, F; Blondiaux, N; Theis, D; Vérin, I; Vachée, A; Dessein, R; Faure, K; Viget, N; Senneville, E; Leroy, O; Maury, F; Just, N; Poissy, J; Mathieu, D; Prévotat, A; Chenivesse, C; Scherpereel, A; Smith, G; Lopez, B; Rosain, J; Frémeaux-Bacchi, V; Hachulla, E; Hatron, P-Y; Bahuaud, M; Batteux, F; Launay, D; Labalette, M; Lefèvre, G

2017-08-01

Screening for primary immunodeficiencies (PIDs) in adults is recommended after two severe bacterial infections. We aimed to evaluate if screening should be performed after the first invasive infection in young adults. Eligible patients were retrospectively identified using hospital discharge and bacteriology databases in three centres during a 3-year period. Eighteen to 40-year-old patients were included if they had experienced an invasive infection with encapsulated bacteria commonly encountered in PIDs (Streptococcus pneumoniae (SP), Neisseria meningitidis (NM), Neisseria gonorrhoeae (NG), Haemophilus influenzae (HI), or group A Streptococcus (GAS)). They were excluded in case of general or local predisposing factors. Immunological explorations and PIDs diagnoses were retrieved from medical records. Serum complement and IgG/A/M testings were systematically proposed at the time of study to patients with previously incomplete PID screening. The study population comprised 38 patients. Thirty-six had experienced a first invasive episode and a PID was diagnosed in seven (19%): two cases of common variable immunodeficiency revealed by SP bacteraemia, one case of idiopathic primary hypogammaglobulinaemia, and two cases of complement (C6 and C7) deficiency revealed by NM meningitis, one case of IgG2/IgG4 subclasses deficiency revealed by GAS bacteraemia, and one case of specific polysaccharide antibody deficiency revealed by HI meningitis. Two patients had previously experienced an invasive infection before the study period: in both cases, a complement deficiency was diagnosed after a second NM meningitis and a second NG bacteraemia, respectively. PID screening should be considered after a first unexplained invasive encapsulated-bacterial infection in young adults. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Characterization of a Complement-Binding Protein, DRS, from Strains of Streptococcus pyogenes Containing the emm12 and emm55 Genes

PubMed Central

Binks, Michael; Sriprakash, K. S.

2004-01-01

An extracellular protein of Streptococcus pyogenes, streptococcal inhibitor of complement (SIC), and its variant, called DRS (distantly related to SIC), are expressed by some S. pyogenes strains. SIC from type 1 (M1) isolates of S. pyogenes interferes with complement-mediated cell lysis, reportedly via its interaction with complement proteins. In this study we demonstrate that S. pyogenes strains carrying emm12 and emm55 (the genes for the M12 and M55 proteins, respectively) express and secrete DRS. This protein, like SIC, binds to the C6 and C7 complement proteins, and competition enzyme-linked immunosorbent assay experiments demonstrate that DRS competes with SIC for C6 and C7 binding. Similarly, SIC competes with DRS for binding to the complement proteins. Despite this, the recombinant DRS preparation showed no significant effect on complement function, as determined by lysis of sensitized sheep erythrocytes. Furthermore, the presence of DRS is not inhibitory to SIC activity. PMID:15213143

Characterization of a complement-binding protein, DRS, from strains of Streptococcus pyogenes containing the emm12 and emm55 genes.

PubMed

Binks, Michael; Sriprakash, K S

2004-07-01

An extracellular protein of Streptococcus pyogenes, streptococcal inhibitor of complement (SIC), and its variant, called DRS (distantly related to SIC), are expressed by some S. pyogenes strains. SIC from type 1 (M1) isolates of S. pyogenes interferes with complement-mediated cell lysis, reportedly via its interaction with complement proteins. In this study we demonstrate that S. pyogenes strains carrying emm12 and emm55 (the genes for the M12 and M55 proteins, respectively) express and secrete DRS. This protein, like SIC, binds to the C6 and C7 complement proteins, and competition enzyme-linked immunosorbent assay experiments demonstrate that DRS competes with SIC for C6 and C7 binding. Similarly, SIC competes with DRS for binding to the complement proteins. Despite this, the recombinant DRS preparation showed no significant effect on complement function, as determined by lysis of sensitized sheep erythrocytes. Furthermore, the presence of DRS is not inhibitory to SIC activity.

The renaissance of complement therapeutics

PubMed Central

Ricklin, Daniel; Mastellos, Dimitrios C.; Reis, Edimara S.; Lambris, John D.

2018-01-01

The increasing number of clinical conditions that involve a pathological contribution from the complement system — many of which affect the kidneys — has spurred a regained interest in therapeutic options to modulate this host defence pathway. Molecular insight, technological advances, and the first decade of clinical experience with the complement-specific drug eculizumab, have contributed to a growing confidence in therapeutic complement inhibition. More than 20 candidate drugs that target various stages of the complement cascade are currently being evaluated in clinical trials, and additional agents are in preclinical development. Such diversity is clearly needed in view of the complex and distinct involvement of complement in a wide range of clinical conditions, including rare kidney disorders, transplant rejection and haemodialysis-induced inflammation. The existing drugs cannot be applied to all complement-driven diseases, and each indication has to be assessed individually. Alongside considerations concerning optimal points of intervention and economic factors, patient stratification will become essential to identify the best complement-specific therapy for each individual patient. This Review provides an overview of the therapeutic concepts, targets and candidate drugs, summarizes insights from clinical trials, and reflects on existing challenges for the development of complement therapeutics for kidney diseases and beyond. PMID:29199277

Phenotypic characterization of adenovirus type 12 temperature-sensitive mutants in productive infection and transformation.

PubMed

Hama, S; Kimura, G

1980-01-01

Eleven temperature-sensitive mutants of adenovirus type 12, capable of forming plaques in human cells at 33 C but not at 39.5 C, were isolated from a stock of a wild-type strain after treatment with either nitrous acid or hydroxylamine. Complementation tests in doubly infected human cells permitted a tentative assignment of eight of these mutants to six complementation groups. Temperature-shift experiments revealed that one mutant is affected early and most of the other mutants are affected late. Only the early mutant, H12ts505, was temperature sensitive in viral DNA replication. Infectious virions of all the mutants except H12ts505 and two of the late mutants produced at 33 C, appeared to be more heat labile than those of the wild type. Only H12ts505 was temperature sensitive for the establishment of transformation of rat 3Y1 cells. One of the late mutants (H12ts504) had an increased transforming ability at the permissive temperature. Results of temperature-shift transformation experiments suggest that a viral function affected in H12ts505 is required for "initiation" of transformation. Some of the growth properties of H12ts505-transformed cells were also temperature dependent, suggesting that a functional expression of a gene mutation in H12ts505 is required to maintain at least some aspects of the transformed state.

Complement-Related Regulates Autophagy in Neighboring Cells.

PubMed

Lin, Lin; Rodrigues, Frederico S L M; Kary, Christina; Contet, Alicia; Logan, Mary; Baxter, Richard H G; Wood, Will; Baehrecke, Eric H

2017-06-29

Autophagy degrades cytoplasmic components and is important for development and human health. Although autophagy is known to be influenced by systemic intercellular signals, the proteins that control autophagy are largely thought to function within individual cells. Here, we report that Drosophila macroglobulin complement-related (Mcr), a complement ortholog, plays an essential role during developmental cell death and inflammation by influencing autophagy in neighboring cells. This function of Mcr involves the immune receptor Draper, suggesting a relationship between autophagy and the control of inflammation. Interestingly, Mcr function in epithelial cells is required for macrophage autophagy and migration to epithelial wounds, a Draper-dependent process. This study reveals, unexpectedly, that complement-related from one cell regulates autophagy in neighboring cells via an ancient immune signaling program. Copyright © 2017 Elsevier Inc. All rights reserved.

Improved understanding of geologic CO{sub 2} storage processes requires risk-driven field experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oldenburg, C.M.

2011-06-01

The need for risk-driven field experiments for CO{sub 2} geologic storage processes to complement ongoing pilot-scale demonstrations is discussed. These risk-driven field experiments would be aimed at understanding the circumstances under which things can go wrong with a CO{sub 2} capture and storage (CCS) project and cause it to fail, as distinguished from accomplishing this end using demonstration and industrial scale sites. Such risk-driven tests would complement risk-assessment efforts that have already been carried out by providing opportunities to validate risk models. In addition to experimenting with high-risk scenarios, these controlled field experiments could help validate monitoring approaches to improvemore » performance assessment and guide development of mitigation strategies.« less

Serological and Genetic Evidence for Altered Complement System Functionality in Systemic Lupus Erythematosus: Findings of the GAPAID Consortium.

PubMed

Prechl, József; Papp, Krisztián; Hérincs, Zoltán; Péterfy, Hajna; Lóránd, Veronika; Szittner, Zoltán; Estonba, Andone; Rovero, Paolo; Paolini, Ilaria; Del Amo, Jokin; Uribarri, Maria; Alcaro, Maria Claudia; Ruiz-Larrañaga, Otsanda; Migliorini, Paola; Czirják, László

2016-01-01

Systemic lupus erythematosus is a chronic autoimmune disease with multifactorial ethiopathogenesis. The complement system is involved in both the early and late stages of disease development and organ damage. To better understand autoantibody mediated complement consumption we examined ex vivo immune complex formation on autoantigen arrays. We recruited patients with SLE (n = 211), with other systemic autoimmune diseases (n = 65) and non-autoimmune control subjects (n = 149). Standard clinical and laboratory data were collected and serum complement levels were determined. The genotype of SNP rs1143679 in the ITGAM gene was also determined. Ex vivo formation of immune complexes, with respect to IgM, IgG, complement C4 and C3 binding, was examined using a functional immunoassay on autoantigen microarray comprising nucleic acids, proteins and lipids. Complement consumption of nucleic acids increased upon binding of IgM and IgG even when serum complement levels were decreased due to consumption in SLE patients. A negative correlation between serum complement levels and ex vivo complement deposition on nucleic acid autoantigens is demonstrated. On the contrary, complement deposition on tested protein and lipid autoantigens showed positive correlation with C4 levels. Genetic analysis revealed that the non-synonymous variant rs1143679 in complement receptor type 3 is associated with an increased production of anti-dsDNA IgG antibodies. Notwithstanding, homozygous carriers of the previously reported susceptible allele (AA) had lower levels of dsDNA specific IgM among SLE patients. Both the non-synonymous variant rs1143679 and the high ratio of nucleic acid specific IgG/IgM were associated with multiple organ involvement. In summary, secondary complement deficiency in SLE does not impair opsonization of nucleic-acid-containing autoantigens but does affect other antigens and potentially other complement dependent processes. Dysfunction of the receptor recognizing complement opsonized immune complexes promotes the development of class-switched autoantibodies targeting nucleic acids.

How Do Students Misunderstand Number Representations?

ERIC Educational Resources Information Center

Herman, Geoffrey L.; Zilles, Craig; Loui, Michael C.

2011-01-01

We used both student interviews and diagnostic testing to reveal students' misconceptions about number representations in computing systems. This article reveals that students who have passed an undergraduate level computer organization course still possess surprising misconceptions about positional notations, two's complement representation, and…

Complement in Action: An Analysis of Patent Trends from 1976 Through 2011.

PubMed

Yang, Kun; Deangelis, Robert A; Reed, Janet E; Ricklin, Daniel; Lambris, John D

2013-01-01

Complement is an essential part of the innate immune response. It interacts with diverse endogenous pathways and contributes to the maintenance of homeostasis, the modulation of adaptive immune responses, and the development of various pathologies. The potential usefulness, in both research and clinical settings, of compounds that detect or modulate complement activity has resulted in thousands of publications on complement-related innovations in fields such as drug discovery, disease diagnosis and treatment, and immunoassays, among others. This study highlights the distribution and publication trends of patents related to the complement system that were granted by the United States Patent and Trademark Office from 1976 to the present day. A comparison to complement-related documents published by the World Intellectual Property Organization is also included. Statistical analyses revealed increasing diversity in complement-related research interests over time. More than half of the patents were found to focus on the discovery of inhibitors; interest in various inhibitor classes exhibited a remarkable transformation from chemical compounds early on to proteins and antibodies in more recent years. Among clinical applications, complement proteins and their modulators have been extensively patented for the diagnosis and treatment of eye diseases (especially age-related macular degeneration), graft rejection, cancer, sepsis, and a variety of other inflammatory and immune diseases. All of the patents discussed in this chapter, as well as those from other databases, are available from our newly constructed complement patent database: www.innateimmunity.us/patent .

Complement in action: an analysis of patent trends from 1976 through 2011.

PubMed

Yang, Kun; DeAngelis, Robert A; Reed, Janet E; Ricklin, Daniel; Lambris, John D

2013-01-01

Complement is an essential part of the innate immune response. It interacts with diverse endogenous pathways and contributes to the maintenance of homeostasis, the modulation of adaptive immune responses, and the development of various pathologies. The potential usefulness, in both research and clinical settings, of compounds that detect or modulate complement activity has resulted in thousands of publications on complement-related innovations in fields such as drug discovery, disease diagnosis and treatment, and immunoassays, among others. This study highlights the distribution and publication trends of patents related to the complement system that were granted by the United States Patent and Trademark Office from 1976 to the present day. A comparison to complement-related documents published by the World Intellectual Property Organization is also included. Statistical analyses revealed increasing diversity in complement-related research interests over time. More than half of the patents were found to focus on the discovery of inhibitors; interest in various inhibitor classes exhibited a remarkable transformation from chemical compounds early on to proteins and antibodies in more recent years. Among clinical applications, complement proteins and their modulators have been extensively patented for the diagnosis and treatment of eye diseases (especially age-related macular degeneration), graft rejection, cancer, sepsis, and a variety of other inflammatory and immune diseases. All of the patents discussed in this chapter, as well as those from other databases, are available from our newly constructed complement patent database: www.innateimmunity.us/patent.

Cyclosporine Induces Endothelial Cell Release of Complement-Activating Microparticles

PubMed Central

Renner, Brandon; Klawitter, Jelena; Goldberg, Ryan; McCullough, James W.; Ferreira, Viviana P.; Cooper, James E.; Christians, Uwe

2013-01-01

Defective control of the alternative pathway of complement is an important risk factor for several renal diseases, including atypical hemolytic uremic syndrome. Infections, drugs, pregnancy, and hemodynamic insults can trigger episodes of atypical hemolytic uremic syndrome in susceptible patients. Although the mechanisms linking these clinical events with disease flares are unknown, recent work has revealed that each of these clinical conditions causes cells to release microparticles. We hypothesized that microparticles released from injured endothelial cells promote intrarenal complement activation. Calcineurin inhibitors cause vascular and renal injury and can trigger hemolytic uremic syndrome. Here, we show that endothelial cells exposed to cyclosporine in vitro and in vivo release microparticles that activate the alternative pathway of complement. Cyclosporine-induced microparticles caused injury to bystander endothelial cells and are associated with complement-mediated injury of the kidneys and vasculature in cyclosporine-treated mice. Cyclosporine-induced microparticles did not bind factor H, an alternative pathway regulatory protein present in plasma, explaining their complement-activating phenotype. Finally, we found that in renal transplant patients, the number of endothelial microparticles in plasma increases 2 weeks after starting tacrolimus, and treatment with tacrolimus associated with increased C3 deposition on endothelial microparticles in the plasma of some patients. These results suggest that injury-associated release of endothelial microparticles is an important mechanism by which systemic insults trigger intravascular complement activation and complement-dependent renal diseases. PMID:24092930

Progress and trends in complement therapeutics.

PubMed

Ricklin, Daniel; Lambris, John D

2013-01-01

The past few years have proven to be a highly successful and exciting period for the field of complement-directed drug discovery and development. Driven by promising experiences with the first marketed complement drugs, increased knowledge about the involvement of complement in health and disease, and improvements in structural and analytical techniques as well as animal models of disease, the field has seen a surge in creative approaches to therapeutically intervene at various stages of the cascade. An impressive panel of compounds that show promise in clinical trials is meanwhile being lined up in the pipelines of both small biotechnology and big pharmaceutical companies. Yet with this new focus on complement-targeted therapeutics, important questions concerning target selection, point and length of intervention, safety, and drug delivery emerge. In view of the diversity of the clinical disorders involving abnormal complement activity or regulation, which include both acute and chronic diseases and affect a wide range of organs, diverse yet specifically tailored therapeutic approaches may be needed to shift complement back into balance. This chapter highlights the key changes in the field that shape our current perception of complement-targeted drugs and provides a brief overview of recent strategies and emerging trends. Selected examples of complement-related diseases and inhibitor classes are highlighted to illustrate the diversity and creativity in field.

Progress and Trends in Complement Therapeutics.

PubMed

Ricklin, Daniel; Lambris, John D

2013-01-01

The past few years have proven to be a highly successful and exciting period for the field of complement-directed drug discovery and development. Driven by promising experiences with the first marketed complement drugs, increased knowledge about the involvement of complement in health and disease, and improvements in structural and analytical techniques as well as animal models of disease, the field has seen a surge in creative approaches to therapeutically intervene at various stages of the cascade. An impressive panel of compounds that show promise in clinical trials is meanwhile being lined up in the pipelines of both small biotechnology and big pharmaceutical companies. Yet with this new focus on complement-targeted therapeutics, important questions concerning target selection, point and length of intervention, safety, and drug delivery emerge. In view of the diversity of the clinical disorders involving abnormal complement activity or regulation, which include both acute and chronic diseases and affect a wide range of organs, diverse yet specifically tailored therapeutic approaches may be needed to shift complement back into balance. This chapter highlights the key changes in the field that shape our current perception of complement-targeted drugs and provides a brief overview of recent strategies and emerging trends. Selected examples of complement-related diseases and inhibitor classes are highlighted to illustrate the diversity and creativity in field.

Role of the CipA Scaffoldin Protein in Cellulose Solubilization, as Determined by Targeted Gene Deletion and Complementation in Clostridium thermocellum

PubMed Central

Olson, Daniel G.; Giannone, Richard J.; Hettich, Robert L.

2013-01-01

The CipA scaffoldin protein plays a key role in the Clostridium thermocellum cellulosome. Previous studies have revealed that mutants deficient in binding or solubilizing cellulose also exhibit reduced expression of CipA. To confirm that CipA is, in fact, necessary for rapid solubilization of crystalline cellulose, the gene was deleted from the chromosome using targeted gene deletion technologies. The CipA deletion mutant exhibited a 100-fold reduction in cellulose solubilization rate, although it was eventually able to solubilize 80% of the 5 g/liter cellulose initially present. The deletion mutant was complemented by a copy of cipA expressed from a replicating plasmid. In this strain, Avicelase activity was restored, although the rate was 2-fold lower than that in the wild type and the duration of the lag phase was increased. The cipA coding sequence is located at the beginning of a gene cluster containing several other genes thought to be responsible for the structural organization of the cellulosome, including olpB, orf2p, and olpA. Tandem mass spectrometry revealed a 10-fold reduction in the expression of olpB, which may explain the lower growth rate. This deletion experiment adds further evidence that CipA plays a key role in cellulose solubilization by C. thermocellum, and it raises interesting questions about the differential roles of the anchor scaffoldin proteins OlpB, Orf2p, and SdbA. PMID:23204466

Mannose-binding lectin binds to Ebola and Marburg envelope glycoproteins, resulting in blocking of virus interaction with DC-SIGN and complement-mediated virus neutralization.

PubMed

Ji, Xin; Olinger, Gene G; Aris, Sheena; Chen, Ying; Gewurz, Henry; Spear, Gregory T

2005-09-01

Mannose-binding lectin (MBL), a serum lectin that mediates innate immune functions including activation of the lectin complement pathway, binds to carbohydrates expressed on some viral glycoproteins. In this study, the ability of MBL to bind to virus particles pseudotyped with Ebola and Marburg envelope glycoproteins was evaluated. Virus particles bearing either Ebola (Zaire strain) or Marburg (Musoke strain) envelope glycoproteins bound at significantly higher levels to immobilized MBL compared with virus particles pseudotyped with vesicular stomatitis virus glycoprotein or with no virus glycoprotein. As observed in previous studies, Ebola-pseudotyped virus bound to cells expressing the lectin DC-SIGN (dendritic cell-specific intercellular adhesion molecule 3-grabbing non-integrin). However, pre-incubation of virus with MBL blocked DC-SIGN-mediated binding to cells, suggesting that the two lectins bind at the same or overlapping sites on the Ebola glycoprotein. Neutralization experiments showed that virus pseudotyped with Ebola or Marburg (Musoke) glycoprotein was neutralized by complement, while the Marburg (Ravn strain) glycoprotein-pseudotyped virus was less sensitive to neutralization. Neutralization was partially mediated through the lectin complement pathway, since a complement source deficient in MBL was significantly less effective at neutralizing viruses pseudotyped with filovirus glycoproteins and addition of purified MBL to the MBL-deficient complement increased neutralization. These experiments demonstrated that MBL binds to filovirus envelope glycoproteins resulting in important biological effects and suggest that MBL can interact with filoviruses during infection in humans.

"Girls Are as Good as Boys at Math" Implies That Boys Are Probably Better: A Study of Expressions of Gender Equality.

PubMed

Chestnut, Eleanor K; Markman, Ellen M

2018-06-28

Although "Girls are as good as boys at math" explicitly expresses equality, we predict it could nevertheless suggest that boys have more raw talent. In statements with this subject-complement structure, the item in the complement position serves as the reference point and is thus considered more typical and prominent. This explains why "Tents are like houses," for instance, sounds better than "Houses are like tents"-people generally think of houses as more typical. For domains about ability, the reference point should be the item that is typically more skilled. We further propose that the reference point should be naturally more skilled. In two experiments, we presented adults with summaries of actual scientific evidence for gender equality in math (Experiment 1) or verbal ability (Experiment 2), but we manipulated whether the reference point in the statements of equality in the summaries (e.g., "Boys' verbal ability is as good as girls'") was girls or boys. As predicted, adults attributed more natural ability to each gender when it was in the complement rather than subject position. Yet, in Experiment 3, we found that when explicitly asked, participants judged that such sentences were not biased in favor of either gender, indicating that subject-complement statements must be transmitting this bias in a subtle way. Thus, statements such as "Girls are as good as boys at math" can actually backfire and perpetuate gender stereotypes about natural ability. © 2018 Cognitive Science Society, Inc.

Expression of complement membrane regulators membrane cofactor protein (CD46), decay accelerating factor (CD55), and protectin (CD59) in human malignant gliomas.

PubMed Central

Mäenpää, A.; Junnikkala, S.; Hakulinen, J.; Timonen, T.; Meri, S.

1996-01-01

Gliomas are malignant brain tumors, which, despite recent progress in surgical and radiological treatment, still have a poor prognosis. Since gliomas apparently resist immunological clearance mechanisms, we became interested in examining bow gliomas resist killing by the human complement system. The resistance of human cells to complement-mediated damage is, in large part, mediated by specific inhibitors of complement:membrane cofactor protein (CD46), decay-accelerating factor (CD55), and protectin (CD59). In the present study we examined the expression of complement regulators in 14 human glioma tumors and in 7 glioma cell lines (U251, U87, HS683, U373, U138, U118, and H2). Protectin was found to be strongly expressed by all glioma tumors and cell lines. Northern blotting analysis demonstrated the typical pattern of four to five protectin mRNAs in the glioma cells. Except for blood vessels, the expression of decay-accelerating factor was weak or absent in the tumors in situ, whereas in the cell lines its expression varied, ranging from negative to intermediate. Membrane cofactor protein was moderately expressed by all the cell lines but only weakly in the tumors. Cell-killing experiments demonstrated that the glioma cell lines were exceptionally resistant to C-mediated lysis. Five of the seven cell lines (U373, HS683, U118, U138, and H2) resisted complement lysis under conditions where most other cell lines were sensitive to killing. Neutralization experiments using specific monoclonal antibodies indicated that protectin was functionally the most important complement regulator in the glioma cells. The killing of the U87 and U251 cells could be significantly increased by a blocking anti-protectin monoclonal antibody, whereas for the other cell lines only moderate or no response was observed. The H2 cell line resisted killing by all antibodies and by complement. These results show that protectin is the most important complement regulator on human glioma cells. The exceptional complement resistance of some glioma cell lines suggests that they may utilize other, hitherto less well characterized, mechanisms to resist complement killing. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 6 Figure 7 PMID:8644856

Streptococcus pyogenes Endopeptidase O Contributes to Evasion from Complement-mediated Bacteriolysis via Binding to Human Complement Factor C1q*

PubMed Central

Honda-Ogawa, Mariko; Sumitomo, Tomoko; Mori, Yasushi; Hamd, Dalia Talat; Ogawa, Taiji; Yamaguchi, Masaya; Nakata, Masanobu; Kawabata, Shigetada

2017-01-01

Streptococcus pyogenes secretes various virulence factors for evasion from complement-mediated bacteriolysis. However, full understanding of the molecules possessed by this organism that interact with complement C1q, an initiator of the classical complement pathway, remains elusive. In this study, we identified an endopeptidase of S. pyogenes, PepO, as an interacting molecule, and investigated its effects on complement immunity and pathogenesis. Enzyme-linked immunosorbent assay and surface plasmon resonance analysis findings revealed that S. pyogenes recombinant PepO bound to human C1q in a concentration-dependent manner under physiological conditions. Sites of inflammation are known to have decreased pH levels, thus the effects of PepO on bacterial evasion from complement immunity was analyzed in a low pH condition. Notably, under low pH conditions, PepO exhibited a higher affinity for C1q as compared with IgG, and PepO inhibited the binding of IgG to C1q. In addition, pepO deletion rendered S. pyogenes more susceptible to the bacteriocidal activity of human serum. Also, observations of the morphological features of the pepO mutant strain (ΔpepO) showed damaged irregular surfaces as compared with the wild-type strain (WT). WT-infected tissues exhibited greater severity and lower complement activity as compared with those infected by ΔpepO in a mouse skin infection model. Furthermore, WT infection resulted in a larger accumulation of C1q than that with ΔpepO. Our results suggest that interaction of S. pyogenes PepO with C1q interferes with the complement pathway, which enables S. pyogenes to evade complement-mediated bacteriolysis under acidic conditions, such as seen in inflammatory sites. PMID:28154192

Deletion of Crry and DAF on murine platelets stimulates thrombopoiesis and increases factor H-dependent resistance of peripheral platelets to complement attack.

PubMed

Barata, Lidia; Miwa, Takashi; Sato, Sayaka; Kim, David; Mohammed, Imran; Song, Wen-Chao

2013-03-15

Complement receptor 1-related gene/protein y (Crry) and decay-accelerating factor (DAF) are two murine membrane C3 complement regulators with overlapping functions. Crry deletion is embryonically lethal whereas DAF-deficient mice are generally healthy. Crry(-/-)DAF(-/-) mice were viable on a C3(-/-) background, but platelets from such mice were rapidly destroyed when transfused into C3-sufficient mice. In this study, we used the cre-lox system to delete platelet Crry in DAF(-/-) mice and studied Crry/DAF-deficient platelet development in vivo. Rather than displaying thrombocytopenia, Pf4-Cre(+)-Crry(flox/flox) mice had normal platelet counts and their peripheral platelets were resistant to complement attack. However, chimera mice generated with Pf4-Cre(+)-Crry(flox/flox) bone marrows showed platelets from C3(-/-) but not C3(+/+) recipients to be sensitive to complement activation, suggesting that circulating platelets in Pf4-Cre(+)-Crry(flox/flox) mice were naturally selected in a complement-sufficient environment. Notably, Pf4-Cre(+)-Crry(flox/flox) mouse platelets became complement susceptible when factor H function was blocked. Examination of Pf4-Cre(+)-Crry(flox/flox) mouse bone marrows revealed exceedingly active thrombopoiesis. Thus, under in vivo conditions, Crry/DAF deficiency on platelets led to abnormal platelet turnover, but peripheral platelet count was compensated for by increased thrombopoiesis. Selective survival of Crry/DAF-deficient platelets aided by factor H protection and compensatory thrombopoiesis demonstrates the cooperation between membrane and fluid phase complement inhibitors and the body's ability to adaptively respond to complement regulator deficiencies.

Theory of mind in SLI revisited: links with syntax, comparisons with ASD.

PubMed

Durrleman, Stephanie; Burnel, Morgane; Reboul, Anne

2017-11-01

According to the linguistic determinism approach, knowledge of sentential complements such as: John says that the earth is flat plays a crucial role in theory of mind (ToM) development by providing a means to represent explicitly people's mental attitudes and beliefs. This approach predicts that mastery of complements determines successful belief reasoning across explicit ToM tasks, even low-verbal ones, and across populations. (1) To investigate the link between a low-verbal ToM-task and complements in Specific Language Impairment (SLI), (2) To determine whether this population shows similar ToM performance to that of children with Autism Spectrum Disorder (ASD) or those with Typical Development (TD) once these groups are matched on competency for complements, (3) To explore whether complements conveying a falsehood without jeopardizing the veracity of the entire sentence, such as complements of verbs of communication, are more crucial for belief attribution than complements which do not have this property, namely complements of verbs of perception, (?John sees that the earth is flat). Children with SLI (n = 20), with ASD (n = 34) and TD (n = 30) completed sentence-picture-matching tasks assessing complementation with communication and perception verbs, as well as a picture-sequencing task assessing ToM. Children were furthermore evaluated for general grammatical and lexical abilities and non-verbal IQ. Results reveal that competency on complements relates to ToM performance with a low-verbal task in SLI, and that SLI, ASD and TD groups of equivalent performance on complements also perform similarly for ToM. Results further suggest that complements with an independent truth-value are the only ones to show a significant relation to ToM performance after teasing out the impact of non-verbal reasoning. This study suggests that clinical groups of different aetiologies as well as TD children perform comparably for ToM once they have similar complementation skills. Findings further highlight that specific types of complements, namely those with an independent truth value, relate in a special way to mentalizing. Future work should determine whether these specific structures could be effective in ToM remediation programmes. © 2017 Royal College of Speech and Language Therapists.

Dengue-Immune Humans Have Higher Levels of Complement-Independent Enhancing Antibody than Complement-Dependent Neutralizing Antibody.

PubMed

Yamanaka, Atsushi; Konishi, Eiji

2017-09-25

Dengue is the most important arboviral disease worldwide. We previously reported that most inhabitants of dengue-endemic countries who are naturally immune to the disease have infection-enhancing antibodies whose in vitro activity does not decrease in the presence of complement (complement-independent enhancing antibodies, or CiEAb). Here, we compared levels of CiEAb and complement-dependent neutralizing antibodies (CdNAb) in dengue-immune humans. A typical antibody dose-response pattern obtained in our assay system to measure the balance between neutralizing and enhancing antibodies showed both neutralizing and enhancing activities depending on serum dilution factor. The addition of complement to the assay system increased the activity of neutralizing antibodies at lower dilutions, indicating the presence of CdNAb. In contrast, similar dose-response curves were obtained with and without complement at higher dilutions, indicating higher levels of CiEAb than CdNAb. For experimental support for the higher CiEAb levels, a cocktail of mouse monoclonal antibodies against dengue virus type 1 was prepared. The antibody dose-response curves obtained in this assay, with or without complement, were similar to those obtained with human serum samples when a high proportion of D1-V-3H12 (an antibody exhibiting only enhancing activity and thus a model for CiEAb) was used in the cocktail. This study revealed higher-level induction of CiEAb than CdNAb in humans naturally infected with dengue viruses.

Complement factor B expression profile in a spontaneous uveitis model.

PubMed

Zipplies, Johanna K; Kirschfink, Michael; Amann, Barbara; Hauck, Stefanie M; Stangassinger, Manfred; Deeg, Cornelia A

2010-12-01

Equine recurrent uveitis serves as a spontaneous model for human autoimmune uveitis. Unpredictable relapses and ongoing inflammation in the eyes of diseased horses as well as in humans lead to destruction of the retina and finally result in blindness. However, the molecular mechanisms leading to inflammation and retinal degeneration are not well understood. An initial screening for differentially regulated proteins in sera of uveitic cases compared to healthy controls revealed an increase of the alternative pathway complement component factor B in ERU cases. To determine the activation status of the complement system, sera were subsequently examined for complement split products. We could demonstrate a significant higher concentration of the activation products B/Ba, B/Bb, Bb neoantigen, iC3b and C3d in uveitic condition compared to healthy controls, whereas for C5b-9 no differences were detected. Additionally, we investigated complement activation directly in the retina by immunohistochemistry, since it is the main target organ of this autoimmune disease. Interestingly, infiltrating cells co-expressed activated factor Bb neoantigen, complement split product C3d as well as CD68, a macrophage marker. In this study, we could demonstrate activation of the complement system both systemically as well as in the eye, the target organ of spontaneous recurrent uveitis. Based on these novel findings, we postulate a novel role for macrophages in connection with complement synthesis at the site of inflammation. Copyright © 2010 Elsevier GmbH. All rights reserved.

Interaction between M-Like Protein and Macrophage Thioredoxin Facilitates Antiphagocytosis for Streptococcus equi ssp. zooepidemicus

PubMed Central

Ma, Zhe; Zhang, Hui; Zheng, Junxi; Li, Yue; Yi, Li; Fan, Hongjie; Lu, Chengping

2012-01-01

Streptococcus equi ssp. zooepidemicus (S. zooepidemicus, S.z) is one of the common pathogens that can cause septicemia, meningitis, and mammitis in domesticated species. M-like protein (SzP) is an important virulence factor of S. zooepidemicus and contributes to bacterial infection and antiphagocytosis. The interaction between SzP of S. zooepidemicus and porcine thioredoxin (TRX) was identified by the yeast two-hybrid and further confirmed by co-immunoprecipitation. SzP interacted with both reduced and the oxidized forms of TRX without inhibiting TRX activity. Membrane anchored SzP was able to recruit TRX to the surface, which would facilitate the antiphagocytosis of the bacteria. Further experiments revealed that TRX regulated the alternative complement pathway by inhibiting C3 convertase activity and associating with factor H (FH). TRX alone inhibited C3 cleavage and C3a production, and the inhibitory effect was additive when FH was also present. TRX inhibited C3 deposition on the bacterial surface when it was recruited by SzP. These new findings indicated that S. zooepidemicus used SzP to recruit TRX and regulated the alternative complement pathways to evade the host immune phagocytosis. PMID:22384152

T cell-independent and T cell-dependent immunoglobulin G responses to polyomavirus infection are impaired in complement receptor 2-deficient mice.

PubMed

Szomolanyi-Tsuda, Eva; Seedhom, Mina O; Carroll, Michael C; Garcea, Robert L

2006-08-15

Polyomavirus (PyV) infection induces protective T cell-independent (TI) IgM and IgG antibody responses in T cell-deficient mice, but these responses are not generated by immunization with viral proteins or virus like particles. We hypothesized that innate signals contribute to the generation of isotype-switched antiviral antibody responses. We studied the role of complement receptor (CR2) engagement in TI and T cell-dependent (TD) antibody responses to PyV using CR2-deficient mice. Antiviral IgG responses were reduced by 80-40% in CR2-/- mice compared to wild type. Adoptive transfer experiments demonstrated the need for CR2 not only in TD, but also in TI IgG responses to PyV. Transfer of CR2-/- B lymphocytes to SCID mice resulted in TI antiviral IgG responses that corresponded to 10% of that seen in wild-type B cell-reconstituted mice. Thus, our studies revealed a profound dependence of TI and TD antiviral antibody responses on CR2-mediated signals in PyV-infected mice, where the viral antigen is abundant and persistent.

Differential wall growth in gravistimulated corn roots: Its timing and regulation

NASA Technical Reports Server (NTRS)

Serlin, B. S.

1985-01-01

The experiments designed to document cell-wall level changes which occur as a result of their gravistimulation are described. The goal of this research is to elucidate the mechanism and time frame of differential growth following a controlled gravistimulation. To achieve this, rates of wall deposition will be determined by following the incorporation of radioactive monosaccharides into the wall. Complementing this experiment will be a freeze-etch study directed at revealing the spatial arrangment of both newly-deposited microfibrils and microfibrils that were present in the growing root prior to stimulation. The second phase of the proposed research will examine the roles ethylene and Ca(2+) have in the modulation of differential wall changes during gravitropism. Ethylene and Ca(2+) have both been implicated as regulators of the gravitropic response in roots and they have also been implicated as regulators of the gravitropic response in roots and they have also been reported to exert some control on the orientation of microfibrils. Both of these agents will be manipulated in such a way as to reveal whether they have a direct influence on cell wall deposition and microfibrillar alignment during the geotropic response.

Burden experienced by community health volunteers in Taiwan: a survey

PubMed Central

2013-01-01

Background Volunteers in Taiwan complement the delivery of health services by paid health professionals. However, in doing so, community health volunteers experience burdens associated with their activities. The reasons for these burdens and degree to which they are experienced are explored in this paper. Our study adds to international research regarding the burden experienced by volunteers. This project is the first to assess how community health volunteers in Taiwan experience burden. Methods The 20 item Burden on Community Health Volunteer (BCHV) instrument, specifically designed for this project, was administered to 435 volunteers attached to Community Health Promotion Development Centres in northern Taiwan. Results The overall burden experienced by volunteers is relatively low. However, a multivariate adjusted regression analysis revealed significant differences in volunteer burden depending on the number of people each volunteer served on average per week, as well as the volunteer’s marital status and their perceptions about personal health. Volunteers who served many people and who perceived their own health as poor experienced a higher level of burden. Those who were a widow or a widower felt less burdened than others. Conclusions The results of the study identify areas where burden is high and where strategies can be developed to reduce the level of burden experienced by community health volunteers in Taiwan. Community health volunteers in Taiwan complement the role of nurses and other health care providers so their retention is important to ongoing service delivery. PMID:23687966

Evidence that a simpático self-schema accounts for differences in the self-concepts and social behavior of Latinos versus Whites (and Blacks).

PubMed

Holloway, Renee A; Waldrip, Amy M; Ickes, William

2009-05-01

On the basis of the assumption that Latino Americans use a simpático self-schema more than White Americans do, the authors predicted that the effects of this difference would be evident in the participants' self-concepts and social behavior. As predicted, Studies 1 and 2 revealed that Latino participants reported significantly more simpático-related terms in their spontaneous self-concepts than did White participants. Complementing these findings, Study 3a revealed that the level of interactional involvement and the perceived quality of initial same-sex interactions was significantly enhanced by the presence of Latino dyad members. Study 3b tested the prediction that the content of the dyad members' thoughts and feelings would reveal a greater use of the simpático self-schema by the Latino participants. This prediction was confirmed, and follow-up analyses indicated that a simpático self-schema plays an important mediating role in the subjective experience and social behavior of Latino individuals. Copyright (c) 2009 APA, all rights reserved.

Human Properdin Opsonizes Nanoparticles and Triggers a Potent Pro-inflammatory Response by Macrophages without Involving Complement Activation

PubMed Central

Kouser, Lubna; Paudyal, Basudev; Kaur, Anuvinder; Stenbeck, Gudrun; Jones, Lucy A.; Abozaid, Suhair M.; Stover, Cordula M.; Flahaut, Emmanuel; Sim, Robert B.; Kishore, Uday

2018-01-01

Development of nanoparticles as tissue-specific drug delivery platforms can be considerably influenced by the complement system because of their inherent pro-inflammatory and tumorigenic consequences. The complement activation pathways, and its recognition subcomponents, can modulate clearance of the nanoparticles and subsequent inflammatory response and thus alter the intended translational applications. Here, we report, for the first time, that human properdin, an upregulator of the complement alternative pathway, can opsonize functionalized carbon nanotubes (CNTs) via its thrombospondin type I repeat (TSR) 4 and 5. Binding of properdin and TSR4+5 is likely to involve charge pattern/polarity recognition of the CNT surface since both carboxymethyl cellulose-coated carbon nanotubes (CMC-CNT) and oxidized (Ox-CNT) bound these proteins well. Properdin enhanced the uptake of CMC-CNTs by a macrophage cell line, THP-1, mounting a robust pro-inflammatory immune response, as revealed by qRT-PCR, multiplex cytokine array, and NF-κB nuclear translocation analyses. Properdin can be locally synthesized by immune cells in an inflammatory microenvironment, and thus, its interaction with nanoparticles is of considerable importance. In addition, recombinant TSR4+5 coated on the CMC-CNTs inhibited complement consumption by CMC-CNTs, suggesting that nanoparticle decoration with TSR4+5, can be potentially used as a complement inhibitor in a number of pathological contexts arising due to exaggerated complement activation. PMID:29483907

The Group B Streptococcus–Secreted Protein CIP Interacts with C4, Preventing C3b Deposition via the Lectin and Classical Complement Pathways

PubMed Central

Pietrocola, Giampiero; Rindi, Simonetta; Rosini, Roberto; Buccato, Scilla

2016-01-01

The group B Streptococcus (GBS) is a leading cause of neonatal invasive disease. GBS bacteria are surrounded by a thick capsular polysaccharide that is a potent inhibitor of complement deposition via the alternative pathway. Several of its surface molecules can however activate the classical and lectin complement pathways, rendering this species still vulnerable to phagocytic killing. In this study we have identified a novel secreted protein named complement interfering protein (CIP) that downregulates complement activation via the classical and lectin pathways, but not the alternative pathway. The CIP protein showed high affinity toward C4b and inhibited its interaction with C2, presumably preventing the formation of the C4bC2a convertase. Addition of recombinant CIP to GBS cip-negative bacteria resulted in decreased deposition of C3b on their surface and in diminished phagocytic killing in a whole-blood assay. Our data reveal a novel strategy exploited by GBS to counteract innate immunity and could be valuable for the development of anti-infective agents against this important pathogen. PMID:26608922

Life experience of sixth-grade students in analog domains of sixth-grade science textbooks

NASA Astrophysics Data System (ADS)

Wagamon, Barbara J.

This study was conducted to determine if analog domains in sixth grade science textbooks were common to the life experience of sixth grade students and if experience differed according to moderating variables. The researcher reviewed three sixth grade general science textbooks and selected analogies that were unsupported by extended text, photos, or diagrams. Analogies were limited to ones which were unsupported because the intent was to identify students who were ready by virtue of life experience to confront analogies unaided by contextual clues. The researcher designed the Life Experiences in Analog Domains (LEAD) Questionnaire to survey students in 50 analog domains. Subjects of the study were 331 sixth grade students from an urban school district. Thirty were tested with the instrument one year later. Data on age, gender, ethnicity and income were analyzed for variance. Standardized achievement test scores were correlated to the LEAD Questionnaire. Results revealed sharp contrasts of experience by analog domain. Experience in analog domains was indicated 52% of the time overall. There were significant differences in the experience of students grouped by moderating variables. Younger students reported more experience than older students. The higher income group reported more experience than the lower income group. Caucasian students reported more experience overall than African American students. Chi-square tests revealed that differences in scores by ethnicity were not controlled by income. of three skills, reading comprehension, mathematics, and science, reading comprehension was most closely correlated to questionnaire score. Results suggest that many of the sixth grade students in the study may be without experience in analog domains when they encounter analogies in a textbook. Assuming subsequent implementations of the Questionnaire confirm these results, teachers should survey life experience of students and help them develop experiences that complement their science text. Textbook authors should explain all but the simplest analogies.

Species Specificity of Vaccinia Virus Complement Control Protein for the Bovine Classical Pathway Is Governed Primarily by Direct Interaction of Its Acidic Residues with Factor I

PubMed Central

Kumar, Jitendra; Yadav, Viveka Nand; Phulera, Swastik; Kamble, Ashish; Gautam, Avneesh Kumar; Panwar, Hemendra Singh

2017-01-01

ABSTRACT Poxviruses display species tropism—variola virus is a human-specific virus, while vaccinia virus causes repeated outbreaks in dairy cattle. Consistent with this, variola virus complement regulator SPICE (smallpox inhibitor of complement enzymes) exhibits selectivity in inhibiting the human alternative complement pathway and vaccinia virus complement regulator VCP (vaccinia virus complement control protein) displays selectivity in inhibiting the bovine alternative complement pathway. In the present study, we examined the species specificity of VCP and SPICE for the classical pathway (CP). We observed that VCP is ∼43-fold superior to SPICE in inhibiting bovine CP. Further, functional assays revealed that increased inhibitory activity of VCP for bovine CP is solely due to its enhanced cofactor activity, with no effect on decay of bovine CP C3-convertase. To probe the structural basis of this specificity, we utilized single- and multi-amino-acid substitution mutants wherein 1 or more of the 11 variant VCP residues were substituted in the SPICE template. Examination of these mutants for their ability to inhibit bovine CP revealed that E108, E120, and E144 are primarily responsible for imparting the specificity and contribute to the enhanced cofactor activity of VCP. Binding and functional assays suggested that these residues interact with bovine factor I but not with bovine C4(H2O) (a moiety conformationally similar to C4b). Mapping of these residues onto the modeled structure of bovine C4b-VCP-bovine factor I supported the mutagenesis data. Taken together, our data help explain why the vaccine strain of vaccinia virus was able to gain a foothold in domesticated animals. IMPORTANCE Vaccinia virus was used for smallpox vaccination. The vaccine-derived virus is now circulating and causing outbreaks in dairy cattle in India and Brazil. However, the reason for this tropism is unknown. It is well recognized that the virus is susceptible to neutralization by the complement classical pathway (CP). Because the virus encodes a soluble complement regulator, VCP, we examined whether this protein displays selectivity in targeting bovine CP. Our data show that it does exhibit selectivity in inhibiting the bovine CP and that this is primarily determined by its amino acids E108, E120, and E144, which interact with bovine serine protease factor I to inactivate bovine C4b—one of the two subunits of CP C3-convertase. Of note, the variola complement regulator SPICE contains positively charged residues at these positions. Thus, these variant residues in VCP help enhance its potency against the bovine CP and thereby the fitness of the virus in cattle. PMID:28724763

Cysteine proteinase from Streptococcus pyogenes enables evasion of innate immunity via degradation of complement factors.

PubMed

Honda-Ogawa, Mariko; Ogawa, Taiji; Terao, Yutaka; Sumitomo, Tomoko; Nakata, Masanobu; Ikebe, Kazunori; Maeda, Yoshinobu; Kawabata, Shigetada

2013-05-31

Streptococcus pyogenes is an important human pathogen that causes invasive diseases such as necrotizing fasciitis, sepsis, and streptococcal toxic shock syndrome. We investigated the function of a major cysteine protease from S. pyogenes that affects the amount of C1-esterase inhibitor (C1-INH) and other complement factors and aimed to elucidate the mechanism involved in occurrence of streptococcal toxic shock syndrome from the aspect of the complement system. First, we revealed that culture supernatant of a given S. pyogenes strain and recombinant SpeB degraded the C1-INH. Then, we determined the N-terminal sequence of the C1-INH fragment degraded by recombinant SpeB. Interestingly, the region containing one of the identified cleavage sites is not present in patients with C1-INH deficiency. Scanning electron microscopy of the speB mutant incubated in human serum showed the abnormal superficial architecture and irregular oval structure. Furthermore, unlike the wild-type strain, that mutant strain showed lower survival capacity than normal as compared with heat-inactivated serum, whereas it had a significantly higher survival rate in serum without the C1-INH than in normal serum. Also, SpeB degraded multiple complement factors and the membrane attack complex. Flow cytometric analyses revealed deposition of C9, one of the components of membrane the attack complex, in greater amounts on the surface of the speB mutant, whereas lower amounts of C9 were bound to the wild-type strain surface. These results suggest that SpeB can interrupt the human complement system via degrading the C1-INH, thus enabling S. pyogenes to evade eradication in a hostile environment.

Human Tamm-Horsfall protein, a renal specific protein, serves as a cofactor in complement 3b degradation

PubMed Central

2017-01-01

Tamm-Horsfall protein (THP) is an abundant urinary protein of renal origin. We hypothesize that THP can act as an inhibitor of complement since THP binds complement 1q (C1q) of the classical complement pathway, inhibits activation of this pathway, and is important in decreasing renal ischemia-reperfusion injury (a complement-mediated condition). In this study, we began to investigate whether THP interacted with the alternate complement pathway via complement factor H (CFH). THP was shown to bind CFH using ligand blots and in an ELISA (KD of 1 × 10−6 M). Next, the ability of THP to alter CFH’s normal action as it functioned as a cofactor in complement factor I (CFI)–mediated complement 3b (C3b) degradation was investigated. Unexpectedly, control experiments in these in vitro assays suggested that THP, without added CFH, could act as a cofactor in CFI-mediated C3b degradation. This cofactor activity was present equally in THP isolated from 10 different individuals. While an ELISA demonstrated small amounts of CFH contaminating THP samples, these CFH amounts were insufficient to explain the degree of cofactor activity present in THP. An ELISA demonstrated that THP directly bound C3b (KD ~ 5 × 10−8 m), a prerequisite for a protein acting as a C3b degradation cofactor. The cofactor activity of THP likely resides in the protein portion of THP since partially deglycosylated THP still retained cofactor activity. In conclusion, THP appears to participate directly in complement inactivation by its ability to act as a cofactor for C3b degradation, thus adding support to the hypothesis that THP might act as an endogenous urinary tract inhibitor of complement. PMID:28742158

Donor Brain Death Exacerbates Complement-Dependent Ischemia Reperfusion Injury in Transplanted Hearts

PubMed Central

Atkinson, Carl; Floerchinger, Bernhard; Qiao, Fei; Casey, Sarah; Williamson, Tucker; Moseley, Ellen; Stoica, Serban; Goddard, Martin; Ge, Xupeng; Tullius, Stefan G.; Tomlinson, Stephen

2013-01-01

Background Brain death (BD) can immunologically prime the donor organ and is thought to lead to exacerbated ischemia reperfusion injury (IRI) post-transplantation. Using a newly developed mouse model of BD, we investigated the effect of donor BD on post transplant cardiac IRI. We further investigated the therapeutic effect of a targeted complement inhibitor in recipients of BD donor hearts, and addressed the clinical relevance of these studies by analysis of human heart biopsies from BD and domino (living) donors. Methods and Results Hearts from living or brain dead donor C57BL/6 mice were transplanted into C57BL/6 or BALB/c recipients. Recipient mice were treated with the complement inhibitor CR2-Crry or vehicle control (n=6). Isografts were analyzed 48 hours post-transplant for injury, inflammation and complement deposition, and allografts monitored for graft survival. Human cardiac biopsies were analyzed for complement deposition and inflammatory cell infiltration. In the murine model, donor BD exacerbated IRI and graft rejection as demonstrated by increased myocardial injury, serum cardiac troponin, cellular infiltration, inflammatory chemokine and cytokine levels, complement deposition, and decreased graft survival. CR2-Crry treatment of recipients significantly reduced all measured outcomes in grafts from both BD and living donors compared to controls. Analysis of human samples documented the relevance of our experimental findings and revealed exacerbated complement deposition and inflammation in grafts from BD donors compared to grafts from living donors. Conclusions BD exacerbates post-transplant cardiac IRI in mice and humans, and decreases survival of mouse allografts. Further, targeted complement inhibition in recipient mice ameliorates BD-exacerbated IRI. PMID:23443736

AKT1, LKB1, and YAP1 revealed as MYC interactors with NanoLuc-based protein-fragment complementation assay. | Office of Cancer Genomics

Cancer.gov

The c-Myc (MYC) transcription factor is a major cancer driver and a well-validated therapeutic target. However, directly targeting MYC has been challenging. Thus, identifying proteins that interact with and regulate MYC may provide alternative strategies to inhibit its oncogenic activity. Here we report the development of a NanoLuc®-based protein-fragment complementation assay (NanoPCA) and mapping of the MYC protein interaction hub in live mammalian cells.

Chickpea transcription factor CaTLP1 interacts with protein kinases, modulates ROS accumulation and promotes ABA-mediated stomatal closure

PubMed Central

Wardhan, Vijay; Pandey, Aarti; Chakraborty, Subhra; Chakraborty, Niranjan

2016-01-01

Tubby and Tubby-like proteins (TLPs), in mammals, play critical roles in neural development, while its function in plants is largely unknown. We previously demonstrated that the chickpea TLP, CaTLP1, participates in osmotic stress response and might be associated with ABA-dependent network. However, how CaTLP1 is connected to ABA signaling remains unclear. The CaTLP1 was found to be engaged in ABA-mediated gene expression and stomatal closure. Complementation of the yeast yap1 mutant with CaTLP1 revealed its role in ROS scavenging. Furthermore, complementation of Arabidopsis attlp2 mutant displayed enhanced stress tolerance, indicating the functional conservation of TLPs across the species. The presence of ABA-responsive element along with other motifs in the proximal promoter regions of TLPs firmly established their involvement in stress signalling pathways. The CaTLP1 promoter driven GUS expression was restricted to the vegetative organs, especially stem and rosette leaves. Global protein expression profiling of wild-type, attlp2 and complemented Arabidopsis plants revealed 95 differentially expressed proteins, presumably involved in maintaining physiological and biological processes under dehydration. Immunoprecipitation assay revealed that protein kinases are most likely to interact with CaTLP1. This study provides the first demonstration that the TLPs act as module for ABA-mediated stomatal closure possibly via interaction with protein kinase. PMID:27934866

A targeted complement-dependent strategy to improve the outcome of mAb therapy, and characterization in a murine model of metastatic cancer

PubMed Central

Elvington, Michelle; Huang, Yuxiang; Morgan, B. Paul; Qiao, Fei; van Rooijen, Nico; Atkinson, Carl

2012-01-01

Complement inhibitors expressed on tumor cells provide an evasion mechanism against mAb therapy and may modulate the development of an acquired antitumor immune response. Here we investigate a strategy to amplify mAb-targeted complement activation on a tumor cell, independent of a requirement to target and block complement inhibitor expression or function, which is difficult to achieve in vivo. We constructed a murine fusion protein, CR2Fc, and demonstrated that the protein targets to C3 activation products deposited on a tumor cell by a specific mAb, and amplifies mAb-dependent complement activation and tumor cell lysis in vitro. In syngeneic models of metastatic lymphoma (EL4) and melanoma (B16), CR2Fc significantly enhanced the outcome of mAb therapy. Subsequent studies using the EL4 model with various genetically modified mice and macrophage-depleted mice revealed that CR2Fc enhanced the therapeutic effect of mAb therapy via both macrophage-dependent FcγR-mediated antibody-dependent cellular cytotoxicity, and by direct complement-mediated lysis. Complement activation products can also modulate adaptive immunity, but we found no evidence that either mAb or CR2Fc treatment had any effect on an antitumor humoral or cellular immune response. CR2Fc represents a potential adjuvant treatment to increase the effectiveness of mAb therapy of cancer. PMID:22442351

The Surface-Exposed Protein SntA Contributes to Complement Evasion in Zoonotic Streptococcus suis.

PubMed

Deng, Simin; Xu, Tong; Fang, Qiong; Yu, Lei; Zhu, Jiaqi; Chen, Long; Liu, Jiahui; Zhou, Rui

2018-01-01

Streptococcus suis is an emerging zoonotic pathogen causing streptococcal toxic shock like syndrome (STSLS), meningitis, septicemia, and even sudden death in human and pigs. Serious septicemia indicates this bacterium can evade the host complement surveillance. In our previous study, a functionally unknown protein SntA of S. suis has been identified as a heme-binding protein, and contributes to virulence in pigs. SntA can interact with the host antioxidant protein AOP2 and consequently inhibit its antioxidant activity. In the present study, SntA is identified as a cell wall anchored protein that functions as an important player in S. suis complement evasion. The C3 deposition and membrane attack complex (MAC) formation on the surface of sntA -deleted mutant strain Δ sntA are demonstrated to be significantly higher than the parental strain SC-19 and the complementary strain CΔ sntA . The abilities of anti-phagocytosis, survival in blood, and in vivo colonization of Δ sntA are obviously reduced. SntA can interact with C1q and inhibit hemolytic activity via the classical pathway. Complement activation assays reveal that SntA can also directly activate classical and lectin pathways, resulting in complement consumption. These two complement evasion strategies may be crucial for the pathogenesis of this zoonotic pathogen. Concerning that SntA is a bifunctional 2',3'-cyclic nucleotide 2'-phosphodiesterase/3'-nucleotidase in many species of Gram-positive bacteria, these complement evasion strategies may have common biological significance.

Streptococcus pyogenes Endopeptidase O Contributes to Evasion from Complement-mediated Bacteriolysis via Binding to Human Complement Factor C1q.

PubMed

Honda-Ogawa, Mariko; Sumitomo, Tomoko; Mori, Yasushi; Hamd, Dalia Talat; Ogawa, Taiji; Yamaguchi, Masaya; Nakata, Masanobu; Kawabata, Shigetada

2017-03-10

Streptococcus pyogenes secretes various virulence factors for evasion from complement-mediated bacteriolysis. However, full understanding of the molecules possessed by this organism that interact with complement C1q, an initiator of the classical complement pathway, remains elusive. In this study, we identified an endopeptidase of S. pyogenes , PepO, as an interacting molecule, and investigated its effects on complement immunity and pathogenesis. Enzyme-linked immunosorbent assay and surface plasmon resonance analysis findings revealed that S. pyogenes recombinant PepO bound to human C1q in a concentration-dependent manner under physiological conditions. Sites of inflammation are known to have decreased pH levels, thus the effects of PepO on bacterial evasion from complement immunity was analyzed in a low pH condition. Notably, under low pH conditions, PepO exhibited a higher affinity for C1q as compared with IgG, and PepO inhibited the binding of IgG to C1q. In addition, pepO deletion rendered S. pyogenes more susceptible to the bacteriocidal activity of human serum. Also, observations of the morphological features of the pepO mutant strain (Δ pepO ) showed damaged irregular surfaces as compared with the wild-type strain (WT). WT-infected tissues exhibited greater severity and lower complement activity as compared with those infected by Δ pepO in a mouse skin infection model. Furthermore, WT infection resulted in a larger accumulation of C1q than that with Δ pepO. Our results suggest that interaction of S. pyogenes PepO with C1q interferes with the complement pathway, which enables S. pyogenes to evade complement-mediated bacteriolysis under acidic conditions, such as seen in inflammatory sites. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Correction of xeroderma pigmentosum complementation group D mutant cell phenotypes by chromosome and gene transfer: Involvement of the human ERCC2 DNA repair gene

DOE Office of Scientific and Technical Information (OSTI.GOV)

Flejter, W.L.; McDaniel, L.D.; Johns, D.

1992-01-01

Cultured cells from individuals afflicted with the genetically heterogeneous autosomal recessive disorder xeroderma pigmentosum (XP) exhibit sensitivity to UV radiation and defective nucleotide excision repair. Complementation of these mutant phenotypes after the introduction of single human chromosomes from repair-proficient cells into XP cells has provided a means of mapping the genes involved in this disease. The authors now report the phenotypic correction of XP cells from genetic complementation group D (XP-D) by a single human chromosome designated Tneo. Detailed molecular characterization of Tneo revealed a rearranged structure involving human chromosomes 16 and 19, including the excision repair cross-complementing 2 (ERCC2)more » gene from the previously described human DNA repair gene cluster at 19q13.2-q13.3. Direct transfer of a cosmid bearing the ERCC2 gene conferred UV resistance to XP-D cells.« less

Initial characterization of 17 viruses harboring mutant forms of the immediate-early gene of equine herpesvirus 1.

PubMed

Buczynski, Kimberly A; Kim, Seong K; O'Callaghan, Dennis J

2005-10-01

The sole immediate-early (IE) gene of equine herpesvirus 1 (EHV-1) encodes a major regulatory protein of 1487 amino acids (aa) capable of modulating gene expression from both early and late promoters and also of trans-repressing its own promoter. Using a specially designed recombination system and a library of IE linker-insertion, deletion, point, and nonsense mutant constructs that encode forms of the IE protein (IEP) harboring mutations within all five regions, 17 mutant viruses were generated and characterized. Ribonuclease protection analyses revealed that all 17 mutants synthesize the IE mRNA in RK-13 cells, whereas those that failed to replicate on non-complementing RK-13 cells displayed a defect in the transcription of either an important early gene (EICP0) and/or an essential late gene (glycoprotein D). Western blot analyses showed that the IEP was synthesized and detectable in cells infected with each mutant virus, including those mutants that failed to replicate on non-complementing RK-13 cells. Eleven of the 17 mutants were capable of growth on non-complementing RK-13 cells, whereas mutant viruses with deletions within the serine-rich tract (SRT), nucleus localization signal (NLS), or DNA-binding domain (DBD) were capable of growth only on the IEP-producing cell line (IE13.1). Lastly, temperature shift experiments revealed that mutant viruses containing deletions within the C-terminus (KyAn1029 and KyAn1411) or within the SRT (KyADeltaSRT2) of the IEP exhibited a temperature-sensitive phenotype in that these viruses, in contrast to the parent KyA, failed to replicate at 39 degrees C. Overall, these results indicate that the C-terminus of the IEP is not essential for IEP function in cell culture, but this region contains elements that enhance the function(s) of the IEP. The initial characterization of these 17 EHV-1 mutants has shown that sequences totaling at least 43% of the IEP are not essential for virus replication in cell culture.

The Group B Streptococcus-Secreted Protein CIP Interacts with C4, Preventing C3b Deposition via the Lectin and Classical Complement Pathways.

PubMed

Pietrocola, Giampiero; Rindi, Simonetta; Rosini, Roberto; Buccato, Scilla; Speziale, Pietro; Margarit, Immaculada

2016-01-01

The group B Streptococcus (GBS) is a leading cause of neonatal invasive disease. GBS bacteria are surrounded by a thick capsular polysaccharide that is a potent inhibitor of complement deposition via the alternative pathway. Several of its surface molecules can however activate the classical and lectin complement pathways, rendering this species still vulnerable to phagocytic killing. In this study we have identified a novel secreted protein named complement interfering protein (CIP) that downregulates complement activation via the classical and lectin pathways, but not the alternative pathway. The CIP protein showed high affinity toward C4b and inhibited its interaction with C2, presumably preventing the formation of the C4bC2a convertase. Addition of recombinant CIP to GBS cip-negative bacteria resulted in decreased deposition of C3b on their surface and in diminished phagocytic killing in a whole-blood assay. Our data reveal a novel strategy exploited by GBS to counteract innate immunity and could be valuable for the development of anti-infective agents against this important pathogen. Copyright © 2015 by The American Association of Immunologists, Inc.

Chimeras of human complement C9 reveal the site recognized by complement regulatory protein CD59.

PubMed

Hüsler, T; Lockert, D H; Kaufman, K M; Sodetz, J M; Sims, P J

1995-02-24

CD59 antigen is a membrane glycoprotein that inhibits the activity of the C9 component of the C5b-9 membrane attack complex, thereby protecting human cells from lysis by human complement. The complement-inhibitory activity of CD59 is species-selective and is most effective toward C9 derived from human or other primate plasma. By contrast, rabbit C9, which can substitute for human C9 in the membrane attack complex, mediates unrestricted lysis of human cells. To identify the peptide segment of human C9 that is recognized by CD59, rabbit C9 cDNA clones were isolated, characterized, and used to construct hybrid cDNAs for expression of full-length human/rabbit C9 chimeras in COS-7 cells. All resulting chimeras were hemolytically active, when tested against chicken erythrocytes bearing C5b-8 complexes. Assays performed in the presence or absence of CD59 revealed that this inhibitor reduced the hemolytic activity of those chimeras containing human C9 sequence between residues 334-415, irrespective of whether the remainder of the protein contained human or rabbit sequence. By contrast, when this segment of C9 contained rabbit sequence, lytic activity was unaffected by CD59. These data establish that human C9 residues 334-415 contain the site recognized by CD59, and they suggest that sequence variability within this segment of C9 is responsible for the observed species-selective inhibitory activity of CD59.

Acquisition of C1 inhibitor by Bordetella pertussis virulence associated gene 8 results in C2 and C4 consumption away from the bacterial surface

PubMed Central

Hovingh, Elise S.; Kuipers, Betsy; Pinelli, Elena; Rooijakkers, Suzan H. M.

2017-01-01

Whooping cough, or pertussis, is a contagious disease of the respiratory tract that is re-emerging worldwide despite high vaccination coverage. The causative agent of this disease is the Gram-negative Bordetella pertussis. Knowledge on complement evasion strategies of this pathogen is limited. However, this is of great importance for future vaccine development as it has become apparent that a novel pertussis vaccine is needed. Here, we unravel the effect of Virulence associated gene 8 (Vag8) of B. pertussis on the human complement system at the molecular level. We show that both recombinant and endogenously secreted Vag8 inhibit complement deposition on the bacterial surface at the level of C4b. We reveal that Vag8 binding to human C1-inhibitor (C1-inh) interferes with the binding of C1-inh to C1s, C1r and MASP-2, resulting in the release of active proteases that subsequently cleave C2 and C4 away from the bacterial surface. We demonstrate that the depletion of these complement components in the bacterial surrounding and subsequent decreased deposition on B. pertussis leads to less complement-mediated bacterial killing. Vag8 is the first protein described that specifically prevents C1s, C1r and MASP-2 binding to C1-inh and thereby mediates complement consumption away from the bacterial surface. Unravelling the mechanism of this unique complement evasion strategy of B. pertussis is one of the first steps towards understanding the interactions between the first line of defense complement and B. pertussis. PMID:28742139

Acquisition of C1 inhibitor by Bordetella pertussis virulence associated gene 8 results in C2 and C4 consumption away from the bacterial surface.

PubMed

Hovingh, Elise S; van den Broek, Bryan; Kuipers, Betsy; Pinelli, Elena; Rooijakkers, Suzan H M; Jongerius, Ilse

2017-07-01

Whooping cough, or pertussis, is a contagious disease of the respiratory tract that is re-emerging worldwide despite high vaccination coverage. The causative agent of this disease is the Gram-negative Bordetella pertussis. Knowledge on complement evasion strategies of this pathogen is limited. However, this is of great importance for future vaccine development as it has become apparent that a novel pertussis vaccine is needed. Here, we unravel the effect of Virulence associated gene 8 (Vag8) of B. pertussis on the human complement system at the molecular level. We show that both recombinant and endogenously secreted Vag8 inhibit complement deposition on the bacterial surface at the level of C4b. We reveal that Vag8 binding to human C1-inhibitor (C1-inh) interferes with the binding of C1-inh to C1s, C1r and MASP-2, resulting in the release of active proteases that subsequently cleave C2 and C4 away from the bacterial surface. We demonstrate that the depletion of these complement components in the bacterial surrounding and subsequent decreased deposition on B. pertussis leads to less complement-mediated bacterial killing. Vag8 is the first protein described that specifically prevents C1s, C1r and MASP-2 binding to C1-inh and thereby mediates complement consumption away from the bacterial surface. Unravelling the mechanism of this unique complement evasion strategy of B. pertussis is one of the first steps towards understanding the interactions between the first line of defense complement and B. pertussis.

Trichinella spiralis Paramyosin Binds to C8 and C9 and Protects the Tissue-Dwelling Nematode from Being Attacked by Host Complement

PubMed Central

Zhang, Zhifei; Yang, Jing; Wei, Junfei; Yang, Yaping; Chen, Xiaoqin; Zhao, Xi; Gu, Yuan; Cui, Shijuan; Zhu, Xinping

2011-01-01

Background Paramyosin is a thick myofibrillar protein found exclusively in invertebrates. Evidence suggested that paramyosin from helminths serves not only as a structural protein but also as an immunomodulatory agent. We previously reported that recombinant Trichinella spiralis paramyosin (Ts-Pmy) elicited a partial protective immunity in mice. In this study, the ability of Ts-Pmy to bind host complement components and protect against host complement attack was investigated. Methods and Findings In this study, the transcriptional and protein expression levels of Ts-Pmy were determined in T. spiralis newborn larva (NBL), muscle larva (ML) and adult worm developmental stages by RT-PCR and western blot analysis. Expression of Ts-Pmy at the outer membrane was observed in NBL and adult worms using immunogold electron microscopy and immunofluorescence staining. Functional analysis revealed that recombinant Ts-Pmy(rTs-Pmy) strongly bound to complement components C8 and C9 and inhibited the polymerization of C9 during the formation of the membrane attack complex (MAC). rTs-Pmy also inhibited the lysis of rabbit erythrocytes (ER) elicited by an alternative pathway-activated complement from guinea pig serum. Inhibition of native Ts-Pmy on the surface of NBL with a specific antiserum reduced larvae viability when under the attack of complement in vitro. In vivo passive transfer of anti-Ts-Pmy antiserum and complement-treated larvae into mice also significantly reduced the number of larvae that developed to ML. Conclusion These studies suggest that the outer membrane form of T. spiralis paramyosin plays an important role in the evasion of the host complement attack. PMID:21750743

Complementation of DNA repair defect in xeroderma pigmentosum cells of group C by the transfer of human chromosome 5

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaur, G.P.; Athwal, R.S.

1993-01-01

Complementation of DNA excision repair defect in xeroderma pigmentosum cells of group C (XP-C) has been achieved by the transfer of human chromosome 5. Individual human chromosomes tagged with a selectable marker were transferred to XP-C cells by microcell fusion from mouse-human hybrid cell lines each bearing a single different human chromosome. Analysis of the chromosome transfer clones revealed that introduction of chromosome 5 into XP-C cells corrected the DNA repair defect as well as UV-sensitive phenotypes, while chromosomes 2, 6, 7, 9, 13, 15, 17, and 21 failed to complement. The introduced chromosome 5 in complemented UV[sup r] clonesmore » was distinguished from the parental XP-C chromosomes by polymorphism for dinucleotide (CA)[sub n] repeats at two loci, D5S117 and D5S209. In addition, an intact marked chromosome 5 was rescued into mouse cells from a complemented UV[sup r] clone by microcell fusion. Five subclones of a complemented clone that had lost the marked chromosome 5 exhibited UV-sensitive and repair-deficient phenotypes identical to parental XP-C cells. Concordant loss of the transferred chromosome and reappearance of XP-C phenotype further confirmed the presence of a DNA repair gene on human chromosome 5. 38 refs., 7 figs., 1 tab.« less

Phagocytosis Escape by a Staphylococcus aureus Protein That Connects Complement and Coagulation Proteins at the Bacterial Surface

PubMed Central

Medina, Eva; van Rooijen, Willemien J.; Spaan, András N.; van Kessel, Kok P. M.; Höök, Magnus; Rooijakkers, Suzan H. M.

2013-01-01

Upon contact with human plasma, bacteria are rapidly recognized by the complement system that labels their surface for uptake and clearance by phagocytic cells. Staphylococcus aureus secretes the 16 kD Extracellular fibrinogen binding protein (Efb) that binds two different plasma proteins using separate domains: the Efb N-terminus binds to fibrinogen, while the C-terminus binds complement C3. In this study, we show that Efb blocks phagocytosis of S. aureus by human neutrophils. In vitro, we demonstrate that Efb blocks phagocytosis in plasma and in human whole blood. Using a mouse peritonitis model we show that Efb effectively blocks phagocytosis in vivo, either as a purified protein or when produced endogenously by S. aureus. Mutational analysis revealed that Efb requires both its fibrinogen and complement binding residues for phagocytic escape. Using confocal and transmission electron microscopy we show that Efb attracts fibrinogen to the surface of complement-labeled S. aureus generating a ‘capsule’-like shield. This thick layer of fibrinogen shields both surface-bound C3b and antibodies from recognition by phagocytic receptors. This information is critical for future vaccination attempts, since opsonizing antibodies may not function in the presence of Efb. Altogether we discover that Efb from S. aureus uniquely escapes phagocytosis by forming a bridge between a complement and coagulation protein. PMID:24348255

Genetic analysis of the agrocinopine catabolic region of Agrobacterium tumefaciens Ti plasmid pTiC58, which encodes genes required for opine and agrocin 84 transport.

PubMed Central

Hayman, G T; Beck von Bodman, S; Kim, H; Jiang, P; Farrand, S K

1993-01-01

The acc region, subcloned from pTiC58 of classical nopaline and agrocinopine A and B Agrobacterium tumefaciens C58, allowed agrobacteria to grow using agrocinopine B as the sole source of carbon and energy. acc is approximately 6 kb in size. It consists of at least five genes, accA through accE, as defined by complementation analysis using subcloned fragments and transposon insertion mutations of acc carried on different plasmids within the same cell. All five regions are required for agrocin 84 sensitivity, and at least four are required for agrocinopine and agrocin 84 uptake. The complementation results are consistent with the hypothesis that each of the five regions is separately transcribed. Maxicell experiments showed that the first of these genes, accA, encodes a 60-kDa protein. Analysis of osmotic shock fractions showed this protein to be located in the periplasm. The DNA sequence of the accA region revealed an open reading frame encoding a predicted polypeptide of 59,147 Da. The amino acid sequence encoded by this open reading frame is similar to the periplasmic binding proteins OppA and DppA of Escherichia coli and Salmonella typhimurium and OppA of Bacillus subtilis. Images PMID:8366042

Activation of the classical complement pathway by mannose-binding protein in association with a novel C1s-like serine protease

PubMed Central

1992-01-01

Serum mannose-binding protein (MBP) is a C-type lectin that binds to terminal mannose and N-acetylglucosamine moieties present on surfaces of certain pathogens and activates the classical complement pathway. In the present study, we describe the mechanism underlying the activation triggered by MBP. The human serum MBP fraction was obtained by sequential affinity chromatography on mannan-Sepharose, anti-IgM- Sepharose and anti-MBP-Sepharose in the presence of calcium ions. This fraction contained a C1s-like serine protease as assessed by C4 consumption. The C1s-like serine protease, designated MBP-associated serine protease (MASP), was separated from MBP by rechromatography on anti-MBP-Sepharose in the presence of ethylenediaminetetraacetic acid. MASP exhibited both C4- and C2-consuming activities. The molecular mass of MASP was estimated to be 83 kD with two polypeptides of heavy (66 kD) and light (L) (31 kD) chains linked by disulfide bonds. The serine residue responsible for protease activity is located on the L chain. Reconstitution experiments using MASP and MBP revealed that combination of the two components restores C4- and C2-activating capacity on mannan. Based on analyses of molecular size, antigenicity, and 11 NH2- terminal amino acid sequences of the L chain, we conclude that MASP is a novel protein different from C1r or C1s. Our findings are not in accord with a proposed mechanism by which MBP utilizes the C1r2-C1s2 complex to initiate the classical complement pathway. PMID:1460414

Mutational analysis of Kaposica reveals that bridging of MG2 and CUB domains of target protein is crucial for the cofactor activity of RCA proteins

PubMed Central

Gautam, Avneesh Kumar; Panse, Yogesh; Ghosh, Payel; Reza, Malik Johid; Mullick, Jayati; Sahu, Arvind

2015-01-01

The complement system has evolved to annul pathogens, but its improper regulation is linked with diseases. Efficient regulation of the system is primarily provided by a family of proteins termed regulators of complement activation (RCA). The knowledge of precise structural determinants of RCA proteins critical for imparting the regulatory activities and the molecular events underlying the regulatory processes, nonetheless, is still limited. Here, we have dissected the structural requirements of RCA proteins that are crucial for one of their two regulatory activities, the cofactor activity (CFA), by using the Kaposi’s sarcoma-associated herpesvirus RCA homolog Kaposica as a model protein. We have scanned the entire Kaposica molecule by sequential mutagenesis using swapping and site-directed mutagenesis, which identified residues critical for its interaction with C3b and factor I. Mapping of these residues onto the modeled structure of C3b–Kaposica–factor I complex supported the mutagenesis data. Furthermore, the model suggested that the C3b-interacting residues bridge the CUB (complement C1r-C1s, Uegf, Bmp1) and MG2 (macroglobulin-2) domains of C3b. Thus, it seems that stabilization of the CUB domain with respect to the core of the C3b molecule is central for its CFA. Identification of CFA-critical regions in Kaposica guided experiments in which the equivalent regions of membrane cofactor protein were swapped into decay-accelerating factor. This strategy allowed CFA to be introduced into decay-accelerating factor, suggesting that viral and human regulators use a common mechanism for CFA. PMID:26420870

European Union funded project on the development of a whole complement deficiency screening ELISA-A story of success and an exceptional manager: Mohamed R. Daha.

PubMed

Würzner, Reinhard; Tedesco, Francesco; Garred, Peter; Mollnes, Tom Eirik; Truedsson, Lennart; Turner, Malcolm W; Sommarin, Yngve; Wieslander, Jörgen; Sim, Robert B

2015-11-01

A whole complement ELISA-based assay kit, primarily designed to screen for deficiencies in components of the complement system was developed during a European Union grant involving more than a dozen European scientists and a small-medium enterprise company (Wieslab, which later merged into Eurodiagnostica). The consortium was led by Prof. Mohamed R. Daha who had already guided a preceding European grant which prepared the ground for this endeavor to create a novel and sophisticated complement measurement tool. The final result of the grant was a scientific publication (Seelen et al., 2005, J. Immunol. Methods 296, 187-198) and a commercially available complement deficiency screening kit, WIESLAB(®) Complement system Screen. Thereafter, the group decided to carry on with a grant, located at Innsbruck Medical University, and supported by royalties and unrestricted educational grants from Eurodiagnostica, Malmö, entitled "Search for Applications for WIESLAB(®) Complement system Screen (SAW)" with the aim to look for further applications of this assay. During the latter project the group organized several scientific meetings aimed at evaluating the use of the assay as well as developing further branches of its platform. A look back over almost two decades reveals a great story of excellent research which was also commercially successful, fulfilling the aims of European Union grants. It is also a story of ageless friendship, only possible due to the vision and guidance of an exceptional manager: Moh Daha. Copyright © 2015 Elsevier Ltd. All rights reserved.

Structure of C3b reveals conformational changes that underlie complement activity.

PubMed

Janssen, Bert J C; Christodoulidou, Agni; McCarthy, Andrew; Lambris, John D; Gros, Piet

2006-11-09

Resistance to infection and clearance of cell debris in mammals depend on the activation of the complement system, which is an important component of innate and adaptive immunity. Central to the complement system is the activated form of C3, called C3b, which attaches covalently to target surfaces to amplify complement response, label cells for phagocytosis and stimulate the adaptive immune response. C3b consists of 1,560 amino-acid residues and has 12 domains. It binds various proteins and receptors to effect its functions. However, it is not known how C3 changes its conformation into C3b and thereby exposes its many binding sites. Here we present the crystal structure at 4-A resolution of the activated complement protein C3b and describe the conformational rearrangements of the 12 domains that take place upon proteolytic activation. In the activated form the thioester is fully exposed for covalent attachment to target surfaces and is more than 85 A away from the buried site in native C3 (ref. 5). Marked domain rearrangements in the alpha-chain present an altered molecular surface, exposing hidden and cryptic sites that are consistent with known putative binding sites of factor B and several complement regulators. The structural data indicate that the large conformational changes in the proteolytic activation and regulation of C3 take place mainly in the first conversion step, from C3 to C3b. These insights are important for the development of strategies to treat immune disorders that involve complement-mediated inflammation.

Evolutionary Analysis of Heterochromatin Protein Compatibility by Interspecies Complementation in Saccharomyces

PubMed Central

Zill, Oliver A.; Scannell, Devin R.; Kuei, Jeffrey; Sadhu, Meru; Rine, Jasper

2012-01-01

The genetic bases for species-specific traits are widely sought, but reliable experimental methods with which to identify functionally divergent genes are lacking. In the Saccharomyces genus, interspecies complementation tests can be used to evaluate functional conservation and divergence of biological pathways or networks. Silent information regulator (SIR) proteins in S. bayanus provide an ideal test case for this approach because they show remarkable divergence in sequence and paralog number from those found in the closely related S. cerevisiae. We identified genes required for silencing in S. bayanus using a genetic screen for silencing-defective mutants. Complementation tests in interspecies hybrids identified an evolutionarily conserved Sir-protein-based silencing machinery, as defined by two interspecies complementation groups (SIR2 and SIR3). However, recessive mutations in S. bayanus SIR4 isolated from this screen could not be complemented by S. cerevisiae SIR4, revealing species-specific functional divergence in the Sir4 protein despite conservation of the overall function of the Sir2/3/4 complex. A cladistic complementation series localized the occurrence of functional changes in SIR4 to the S. cerevisiae and S. paradoxus branches of the Saccharomyces phylogeny. Most of this functional divergence mapped to sequence changes in the Sir4 PAD. Finally, a hemizygosity modifier screen in the interspecies hybrids identified additional genes involved in S. bayanus silencing. Thus, interspecies complementation tests can be used to identify (1) mutations in genetically underexplored organisms, (2) loci that have functionally diverged between species, and (3) evolutionary events of functional consequence within a genus. PMID:22923378

Modulation of post-stroke degenerative and regenerative processes and subacute protection by site-targeted inhibition of the alternative pathway of complement.

PubMed

Alawieh, Ali; Elvington, Andrew; Zhu, Hong; Yu, Jin; Kindy, Mark S; Atkinson, Carl; Tomlinson, Stephen

2015-12-30

Complement promotes neuroinflammation and injury in models of stroke. However, complement is also being increasingly implicated in repair and regeneration after central nervous system (CNS) injury, and some complement deficiencies have been shown to provide acute, but not subacute, protection after murine stroke. Here, we investigate the dual role of complement in injury and repair after cerebral ischemia and reperfusion. We used complement-deficient mice and different complement inhibitors in a model of transient middle cerebral artery occlusion to investigate complement-dependent cellular and molecular changes that occur through the subacute phase after stroke. C3 deficiency and site-targeted complement inhibition with either CR2-Crry (inhibits all pathways) or CR2-fH (inhibits alternative pathway) significantly reduced infarct size, reduced apoptotic cell death, and improved neurological deficit score in the acute phase after stroke. However, only in CR2-fH-treated mice was there sustained protection with no evolution of injury in the subacute phase. Whereas both inhibitors significantly reduced microglia/macrophage activation and astrogliosis in the subacute phase, only CR2-fH improved neurological deficit and locomotor function, maintained neurogenesis markers, enhanced neuronal migration, and increased VEGF expression. These findings in CR2-fH-treated mice correlated with improved performance in spatial learning and passive avoidance tasks. The complement anaphylatoxins have been implicated in repair and regenerative mechanisms after CNS injury, and in this context CR2-fH significantly reduced, but did not eliminate the generation of C5a within the brain, unlike CR2-Crry that completely blocked C5a generation. Gene expression profiling revealed that CR2-fH treatment downregulated genes associated with apoptosis, TGFβ signaling, and neutrophil activation, and decreased neutrophil infiltration was confirmed by immunohistochemistry. CR2-fH upregulated genes for neural growth factor and mediators of neurogenesis and neuronal migration. Live animal imaging demonstrated that following intravenous injection, CR2-fH targeted specifically to the post-ischemic brain, with a tissue half-life of 48.5 h. Finally, unlike C3 deficiency, targeted complement inhibition did not increase susceptibility to lethal post-stroke infection, an important consideration for stroke patients. Ischemic brain tissue-targeted and selective inhibition of alternative complement pathway provide self-limiting inhibition of complement activation and reduces acute injury while maintaining complement-dependent recovery mechanisms into the subacute phase after stroke.

Using NMR to Probe the Regio- and Stereochemistry of the Hydration of 1-Hexene

ERIC Educational Resources Information Center

Saba, Shahrokh; Clarke, Donald D.; Iwanoski, Christa; Lobasso, Thomas

2010-01-01

This undergraduate organic laboratory experiment complements previously described and popular experiments on hydration of 1-hexene where students experimentally establish the Markovnikov regioselectivity of alkene hydration. In this experiment, students explore not only the regiochemistry but also the stereochemistry of 1-hexene hydration and…

Electroencephalographic dynamics of musical emotion perception revealed by independent spectral components.

PubMed

Lin, Yuan-Pin; Duann, Jeng-Ren; Chen, Jyh-Horng; Jung, Tzyy-Ping

2010-04-21

This study explores the electroencephalographic (EEG) correlates of emotional experience during music listening. Independent component analysis and analysis of variance were used to separate statistically independent spectral changes of the EEG in response to music-induced emotional processes. An independent brain process with equivalent dipole located in the fronto-central region exhibited distinct δ-band and θ-band power changes associated with self-reported emotional states. Specifically, the emotional valence was associated with δ-power decreases and θ-power increases in the frontal-central area, whereas the emotional arousal was accompanied by increases in both δ and θ powers. The resultant emotion-related component activations that were less interfered by the activities from other brain processes complement previous EEG studies of emotion perception to music.

Wilderness visitor experiences: Lessons from 50 years of research

Treesearch

David N. Cole; Daniel R. Williams

2012-01-01

This paper reviews 50 years of research on the experiences of wilderness visitors. Research on the nature of experiences began with an emphasis on motivations for taking wilderness trips and a focus on the experiential outcomes of wilderness visits. This perspective has been complemented by recent work that more deeply explores the lived experience in wilderness, its...

Seeing science everywhere: A case study of the perceptions of three fifth grade science teachers' complementary use of the arts in the science classroom in an economically distressed county in central Appalachia

NASA Astrophysics Data System (ADS)

McKeen, Angela A.

By employing qualitative methods, this study sought to determine the perceptions three fifth grade science teachers held about using the arts to complement science teaching in an economically distressed county in rural Appalachia and the perceived roles the arts and sciences play in the lives of those living in rural Appalachia. Each case was studied using participant-observer observations, personal journals, archival data, and interviewed using semi-structured, in-depth interview techniques. From these data, unique themes emerged for each of the three cases. Constant comparative analysis was used to analyze the data set for each individual case. A cross-case analysis was then employed to generate the common broad themes among the cases. The findings suggest that Time was perceived as the greatest deterrent to complementing science with aspects of the arts with greater frequency, even when the approach was perceived by the teacher as successful for a greater number of students, especially students who had previously been perceived as having difficulty in the science classroom. The findings also revealed that the more experienced the teacher was in using aspects of the arts to complement hands-on, inquiry science teaching, the more efficacious the teacher's perception was of her own teaching, regardless of overall teaching experience. The approach was perceived as an avenue in building relationships with students and colleagues, thus perceived as ensuring a greater frequency of success for both students and teacher in science classes. It was also perceived as a tool for self-reflection and/or self-critique by the teacher. Finally, the findings further suggested the roles of the arts and sciences in the lives of those living in rural Appalachia were perceived in two distinct ways by participants, depending on the education levels attained by the populations. Findings revealed the arts and sciences were perceived as hobbies or as the continuation of cultural traditions in the lives of those in rural Appalachia who do not further their education. However, the arts and sciences were perceived as a means to personal, financial, and educational success in those members of the population who further their educational levels. These findings suggest that science success and science failure may play a role in the continued stratification of an already marginalized population (i.e. rural Appalachians living in poverty). Findings further reveal that the arts may offer a bridge to those students who were previously perceived as unsuccessful in the science classroom.

Null EPAC Mutants Reveal a Sequential Order of Versatile cAMP Effects during "Drosophila" Aversive Odor Learning

ERIC Educational Resources Information Center

Richlitzki, Antje; Latour, Philipp; Schwärzel, Martin

2017-01-01

Here, we define a role of the cAMP intermediate EPAC in "Drosophila" aversive odor learning by means of null epac mutants. Complementation analysis revealed that EPAC acts downstream from the "rutabaga" adenylyl cyclase and in parallel to protein kinase A. By means of targeted knockdown and genetic rescue we identified mushroom…

Increased HDL cholesterol levels in mice with XX versus XY sex chromosomes

PubMed Central

Link, Jenny C.; Chen, Xuqi; Prien, Christopher; Borja, Mark S.; Hammerson, Bradley; Oda, Michael N.; Arnold, Arthur P.; Reue, Karen

2015-01-01

Objective The molecular mechanisms underlying sex differences in dyslipidemia are poorly understood. We aimed to distinguish genetic and hormonal regulators of sex differences in plasma lipid levels. Approach and Results We assessed the role of gonadal hormones and sex chromosome complement on lipid levels using the Four Core Genotypes mouse model (XX females, XX males, XY females, and XY males). In gonadally intact mice fed a chow diet, lipid levels were influenced by both male–female gonadal sex and XX–XY chromosome complement. Gonadectomy of adult mice revealed that the male–female differences are dependent on acute effects of gonadal hormones. In both intact and gonadectomized animals, XX mice had higher HDL cholesterol (HDL-C) levels than XY mice, regardless of male–female sex. Feeding a cholesterol-enriched diet produced distinct patterns of sex differences in lipid levels compared to a chow diet, revealing the interaction of gonadal and chromosomal sex with diet. Notably, under all dietary and gonadal conditions, HDL-C levels were higher in mice with two X chromosomes compared to mice with an X and Y chromosome. By generating mice with XX, XY and XXY chromosome complements, we determined that the presence of two X chromosomes, and not the absence of the Y chromosome, influences HDL-C concentration. Conclusions We demonstrate that having two X chromosomes versus an X and Y chromosome complement drives sex differences in HDL-C. It is conceivable that increased expression of genes escaping X-inactivation in XX mice regulates downstream processes to establish sexual dimorphism in plasma lipid levels. PMID:26112012

Increased high-density lipoprotein cholesterol levels in mice with XX versus XY sex chromosomes.

PubMed

Link, Jenny C; Chen, Xuqi; Prien, Christopher; Borja, Mark S; Hammerson, Bradley; Oda, Michael N; Arnold, Arthur P; Reue, Karen

2015-08-01

The molecular mechanisms underlying sex differences in dyslipidemia are poorly understood. We aimed to distinguish genetic and hormonal regulators of sex differences in plasma lipid levels. We assessed the role of gonadal hormones and sex chromosome complement on lipid levels using the four core genotypes mouse model (XX females, XX males, XY females, and XY males). In gonadally intact mice fed a chow diet, lipid levels were influenced by both male-female gonadal sex and XX-XY chromosome complement. Gonadectomy of adult mice revealed that the male-female differences are dependent on acute effects of gonadal hormones. In both intact and gonadectomized animals, XX mice had higher HDL cholesterol (HDL-C) levels than XY mice, regardless of male-female sex. Feeding a cholesterol-enriched diet produced distinct patterns of sex differences in lipid levels compared with a chow diet, revealing the interaction of gonadal and chromosomal sex with diet. Notably, under all dietary and gonadal conditions, HDL-C levels were higher in mice with 2 X chromosomes compared with mice with an X and Y chromosome. By generating mice with XX, XY, and XXY chromosome complements, we determined that the presence of 2 X chromosomes, and not the absence of the Y chromosome, influences HDL-C concentration. We demonstrate that having 2 X chromosomes versus an X and Y chromosome complement drives sex differences in HDL-C. It is conceivable that increased expression of genes escaping X-inactivation in XX mice regulates downstream processes to establish sexual dimorphism in plasma lipid levels. © 2015 American Heart Association, Inc.

Proteolysis of complement factors iC3b and C5 by the serine protease prostate-specific antigen in prostatic fluid and seminal plasma.

PubMed

Manning, Michael L; Williams, Simon A; Jelinek, Christine A; Kostova, Maya B; Denmeade, Samuel R

2013-03-15

Prostate-specific Ag (PSA) is a serine protease that is expressed exclusively by normal and malignant prostate epithelial cells. The continued high-level expression of PSA by the majority of men with both high- and low-grade prostate cancer throughout the course of disease progression, even in the androgen-ablated state, suggests that PSA has a role in the pathogenesis of disease. Current experimental and clinical evidence suggests that chronic inflammation, regardless of the cause, may predispose men to prostate cancer. The responsibility of the immune system in immune surveillance and eventually tumor progression is well appreciated but not completely understood. In this study, we used a mass spectrometry-based evaluation of prostatic fluid obtained from diseased prostates after removal by radical prostatectomy to identify potential immunoregulatory proteins. This analysis revealed the presence of Igs and the complement system proteins C3, factor B, and clusterin. Verification of these findings by Western blot confirmed the high-level expression of C3 in the prostatic fluid and the presence of a previously uncharacterized C-terminal C3 cleavage product. Biochemical analysis of this C3 cleavage fragment revealed a putative PSA cleavage site after tyrosine-1348. Purified PSA was able to cleave iC3b and the related complement protein C5. These results suggest a previously uncharacterized function of PSA as an immunoregulatory protease that could help to create an environment hospitable to malignancy through proteolysis of the complement system.

Novel Mutations Causing C5 Deficiency in Three North-African Families.

PubMed

Colobran, Roger; Franco-Jarava, Clara; Martín-Nalda, Andrea; Baena, Neus; Gabau, Elisabeth; Padilla, Natàlia; de la Cruz, Xavier; Pujol-Borrell, Ricardo; Comas, David; Soler-Palacín, Pere; Hernández-González, Manuel

2016-05-01

The complement system plays a central role in defense to encapsulated bacteria through opsonization and membrane attack complex (MAC) dependent lysis. The three activation pathways (classical, lectin, and alternative) converge in the cleavage of C5, which initiates MAC formation and target lysis. C5 deficiency is associated to recurrent infections by Neisseria spp. In the present study, complement deficiency was suspected in three families of North-African origin after one episode of invasive meningitis due to a non-groupable and two uncommon Meningococcal serotypes (E29, Y). Activity of alternative and classical pathways of complement were markedly reduced and the measurement of terminal complement components revealed total C5 absence. C5 gene analysis revealed two novel mutations as causative of the deficiency: Family A propositus carried a homozygous deletion of two adenines in the exon 21 of C5 gene, resulting in a frameshift and a truncated protein (c.2607_2608del/p.Ser870ProfsX3 mutation). Families B and C probands carried the same homozygous deletion of three consecutive nucleotides (CAA) in exon 9 of the C5 gene, leading to the deletion of asparagine 320 (c.960_962del/p.Asn320del mutation). Family studies confirmed an autosomal recessive inheritance pattern. Although sharing the same geographical origin, families B and C were unrelated. This prompted us to investigate this mutation prevalence in a cohort of 768 North-African healthy individuals. We identified one heterozygous carrier of the p.Asn320del mutation (allelic frequency = 0.065 %), indicating that this mutation is present at low frequency in North-African population.

Skipping of exon 27 in C3 gene compromises TED domain and results in complete human C3 deficiency.

PubMed

da Silva, Karina Ribeiro; Fraga, Tatiana Rodrigues; Lucatelli, Juliana Faggion; Grumach, Anete Sevciovic; Isaac, Lourdes

2016-05-01

Primary deficiency of complement C3 is rare and usually associated with increased susceptibility to bacterial infections. In this work, we investigated the molecular basis of complete C3 deficiency in a Brazilian 9-year old female patient with a family history of consanguinity. Hemolytic assays revealed complete lack of complement-mediated hemolytic activity in the patient's serum. While levels of the complement regulatory proteins Factor I, Factor H and Factor B were normal in the patient's and family members' sera, complement C3 levels were undetectable in the patient's serum and were reduced by at least 50% in the sera of the patient's parents and brother. Additionally, no C3 could be observed in the patient's plasma and cell culture supernatants by Western blot. We also observed that patient's skin fibroblasts stimulated with Escherichia coli LPS were unable to secrete C3, which might be accumulated within the cells before being intracellularly degraded. Sequencing analysis of the patient's C3 cDNA revealed a genetic mutation responsible for the complete skipping of exon 27, resulting in the loss of 99 nucleotides (3450-3549) located in the TED domain. Sequencing of the intronic region between the exons 26 and 27 of the C3 gene (nucleotides 6690313-6690961) showed a nucleotide exchange (T→C) at position 6690626 located in a splicing donor site, resulting in the complete skipping of exon 27 in the C3 mRNA. Copyright © 2016. Published by Elsevier GmbH.

Functional analyses of rare genetic variants in complement component C9 identified in patients with age-related macular degeneration.

PubMed

Kremlitzka, Mariann; Geerlings, Maartje J; de Jong, Sarah; Bakker, Bjorn; Nilsson, Sara C; Fauser, Sascha; Hoyng, Carel B; de Jong, Eiko K; den Hollander, Anneke I; Blom, Anna M

2018-05-14

Age-related macular degeneration (AMD) is a progressive disease of the central retina and the leading cause of irreversible vision loss in the western world. The involvement of abnormal complement activation in AMD has been suggested by association of variants in genes encoding complement proteins with disease development. A low-frequency variant (p.P167S) in the complement component C9 (C9) gene was recently shown to be highly associated with AMD, however its functional outcome remains largely unexplored. In this study, we reveal five novel rare genetic variants (p.M45L, p.F62S, p.G126R, p.T170I and p.A529T) in C9 in AMD patients, and evaluate their functional effects in vitro together with the previously identified (p.R118W and p.P167S) C9 variants.Our results demonstrate that the concentration of C9 is significantly elevated in patients' sera carrying the p.M45L, p.F62S, p.P167S and p.A529T variants compared to non-carrier controls. However, no difference can be observed in soluble terminal complement complex levels between the carrier and non-carrier groups. Comparing the polymerization of the C9 variants we reveal that the p.P167S mutant spontaneously aggregates, while the other mutant proteins (except for C9 p.A529T) fail to polymerize in the presence of zinc. Altered polymerization of the p.F62S and p.P167S proteins associated with decreased lysis of sheep erythrocytes and ARPE-19 cells by carriers' sera. Our data suggest that the analysed C9 variants affect only the secretion and polymerization of C9, without influencing its classical lytic activity. Future studies need to be performed to understand the implications of the altered polymerization of C9 in AMD pathology.

Identification of Bacillus subtilis men mutants which lack O-succinylbenzoyl-coenzyme A synthetase and dihydroxynaphthoate synthase.

PubMed Central

Meganathan, R; Bentley, R; Taber, H

1981-01-01

Menaquinone (vitamin K2)-deficient mutants of Bacillus subtilis, whose growth requirement is satisfied by 1,4-dihydroxy-2-naphthoic acid but not by o-succinylbenzoic acid (OSB), have been analyzed for enzymatic defects. Complementation analysis of cell-free extracts of the mutants revealed that there are two groups, as already indicated by genetic analysis. The missing enzyme in each group was identified by complementation of the cell-free extracts with o-succinylbenzoyl-coenzyme A (CoA) synthetase and dihydroxynaphthoate synthase extracted from Mycobacterium phlei. Mutants found to lack dihydroxynaphthoate synthase, and which therefore complement with dihydroxynaphthoate synthase of M. phlei, were designated as menB; those lacking o-succinylbenzoyl-CoA synthetase, and therefore complementing with o-succinylbenzoyl-CoA synthetase, were designated as menE. The menB mutants RB413 (men-325) and RB415 (men-329), when incubated with [2,3-14C2]OSB, produced only the spirodilactone form of OSB in a reaction that was CoA and adenosine 5'-triphosphate dependent. PMID:6780515

Use of eculizumab in crescentic IgA nephropathy: proof of principle and conundrum?

PubMed Central

Ring, Troels; Pedersen, Birgitte Bang; Salkus, Giedrius; Goodship, Timothy H.J.

2015-01-01

IgA nephropathy (IgAN) is characterized by a variable clinical course and multifaceted pathophysiology. There is substantial evidence to suggest that complement activation plays a pivotal role in the pathogenesis of the disease. Therefore, complement inhibition using the humanized anti-C5 monoclonal antibody eculizumab could be a rational treatment. We report here a 16-year-old male with the vasculitic form of IgAN who failed to respond to aggressive conventional therapy including high-dose steroids, cyclophosphamide and plasma exchange and who was treated with four weekly doses of 900 mg eculizumab followed by a single dose of 1200 mg. He responded rapidly to this treatment and has had a stable creatinine around 150 µmol/L (1.67 mg/dL) for >6 months. However, proteinuria was unabated on maximal conventional anti-proteinuric treatment, and a repeat renal biopsy 11 months after presentation revealed severe chronic changes. We believe this case provides proof of principle that complement inhibition may be beneficial in IgAN but also that development of chronicity may be independent of complement. PMID:26413271

Interallelic Complementation at the Suppressor of Forked Locus of Drosophila Reveals Complementation between Suppressor of Forked Proteins Mutated in Different Regions

PubMed Central

Simonelig, M.; Elliott, K.; Mitchelson, A.; O'Hare, K.

1996-01-01

The Su(f) protein of Drosophila melanogaster shares extensive homologies with proteins from yeast (RNA14) and man (77 kD subunit of cleavage stimulation factor) that are required for 3' end processing of mRNA. These homologies suggest that su(f) is involved in mRNA 3' end formation and that some aspects of this process are conserved throughout eukaryotes. We have investigated the genetic and molecular complexity of the su(f) locus. The su(f) gene is transcribed to produce three RNAs and could encode two proteins. Using constructs that contain different parts of the locus, we show that only the larger predicted gene product of 84 kD is required for the wild-type function of su(f). Some lethal alleles of su(f) complement to produce viable combinations. The structures of complementing and noncomplementing su(f) alleles indicate that 84-kD Su(f) proteins mutated in different domains can act in combination for partial su(f) function. Our results suggest protein-protein interaction between or within wild-type Su(f) molecules. PMID:8846900

A selection that reports on protein–protein interactions within a thermophilic bacterium

PubMed Central

Nguyen, Peter Q.; Silberg, Jonathan J.

2010-01-01

Many proteins can be split into fragments that exhibit enhanced function upon fusion to interacting proteins. While this strategy has been widely used to create protein-fragment complementation assays (PCAs) for discovering protein–protein interactions within mesophilic organisms, similar assays have not yet been developed for studying natural and engineered protein complexes at the temperatures where thermophilic microbes grow. We describe the development of a selection for protein–protein interactions within Thermus thermophilus that is based upon growth complementation by fragments of Thermotoga neapolitana adenylate kinase (AKTn). Complementation studies with an engineered thermophile (PQN1) that is not viable above 75°C because its adk gene has been replaced by a Geobacillus stearothermophilus ortholog revealed that growth could be restored at 78°C by a vector that coexpresses polypeptides corresponding to residues 1–79 and 80–220 of AKTn. In contrast, PQN1 growth was not complemented by AKTn fragments harboring a C156A mutation within the zinc-binding tetracysteine motif unless these fragments were fused to Thermotoga maritima chemotaxis proteins that heterodimerize (CheA and CheY) or homodimerize (CheX). This enhanced complementation is interpreted as arising from chemotaxis protein–protein interactions, since AKTn-C156A fragments having only one polypeptide fused to a chemotaxis protein did not complement PQN1 to the same extent. This selection increases the maximum temperature where a PCA can be used to engineer thermostable protein complexes and to map protein–protein interactions. PMID:20418388

A selection that reports on protein-protein interactions within a thermophilic bacterium.

PubMed

Nguyen, Peter Q; Silberg, Jonathan J

2010-07-01

Many proteins can be split into fragments that exhibit enhanced function upon fusion to interacting proteins. While this strategy has been widely used to create protein-fragment complementation assays (PCAs) for discovering protein-protein interactions within mesophilic organisms, similar assays have not yet been developed for studying natural and engineered protein complexes at the temperatures where thermophilic microbes grow. We describe the development of a selection for protein-protein interactions within Thermus thermophilus that is based upon growth complementation by fragments of Thermotoga neapolitana adenylate kinase (AK(Tn)). Complementation studies with an engineered thermophile (PQN1) that is not viable above 75 degrees C because its adk gene has been replaced by a Geobacillus stearothermophilus ortholog revealed that growth could be restored at 78 degrees C by a vector that coexpresses polypeptides corresponding to residues 1-79 and 80-220 of AK(Tn). In contrast, PQN1 growth was not complemented by AK(Tn) fragments harboring a C156A mutation within the zinc-binding tetracysteine motif unless these fragments were fused to Thermotoga maritima chemotaxis proteins that heterodimerize (CheA and CheY) or homodimerize (CheX). This enhanced complementation is interpreted as arising from chemotaxis protein-protein interactions, since AK(Tn)-C156A fragments having only one polypeptide fused to a chemotaxis protein did not complement PQN1 to the same extent. This selection increases the maximum temperature where a PCA can be used to engineer thermostable protein complexes and to map protein-protein interactions.

Learning on the Job: Cooperative Education, Internships and Engineering Problem-Solving Skills

ERIC Educational Resources Information Center

Yin, Alexander C.

2009-01-01

Cooperative education (co-op) and internships are forms of experiential education that allow students to complement their classroom experiences with work experience. This study examines the influence of co-op and internships on engineering problem-solving skills by answering the following research questions: (1) Does experience in cooperative…

Augmented Reality Learning Experiences: Survey of Prototype Design and Evaluation

ERIC Educational Resources Information Center

Santos, Marc Ericson C.; Chen, Angie; Taketomi, Takafumi; Yamamoto, Goshiro; Miyazaki, Jun; Kato, Hirokazu

2014-01-01

Augmented reality (AR) technology is mature for creating learning experiences for K-12 (pre-school, grade school, and high school) educational settings. We reviewed the applications intended to complement traditional curriculum materials for K-12. We found 87 research articles on augmented reality learning experiences (ARLEs) in the IEEE Xplore…

Oxorhenium Complexes for Catalytic Hydrosilylation and Hydrolytic Hydrogen Production: A Multiweek Advanced Laboratory Experiment for Undergraduate Students

ERIC Educational Resources Information Center

Ison, A.; Ison, E. A.; Perry, C. M.

2017-01-01

An effective way of teaching undergraduates a full complement of research skills is through a multiweek advanced laboratory experiment. Here we outline a comprehensive set of experiments adapted from current primary literature focusing on organic and inorganic synthesis, catalysis, reactivity, and reaction kinetics. The catalyst,…

Effect of complementation of cattle cooling systems with feedline soakers on lactating dairy cows in a desert environment.

PubMed

Ortiz, X A; Smith, J F; Bradford, B J; Harner, J P; Oddy, A

2011-02-01

Two experiments were conducted on a commercial dairy farm in eastern Saudi Arabia to investigate the effects of Korral Kool (KK; Korral Kool Inc., Mesa, AZ) cattle cooling systems complemented with feedline soakers on core body temperature (CBT) of dairy cows. In both experiments, cows had access to KK 24h/d. In the first experiment, 7 primiparous and 6 multiparous lactating Holstein dairy cows were assigned to 1 of 2 pens, which were assigned randomly to treatment sequence over 4 d in a switchback design. Soakers were on (ON24) or off (OFF24) for 24h/d. For the second experiment, 20 multiparous lactating Holstein cows were assigned randomly to 1 of 2 pens, which were assigned randomly to treatment sequence in a switchback design. This experiment lasted 4 d and feedline soakers alternately remained off or were on (ON12) for 12h/d. In experiment 1, average ambient temperature was 30 ± 0.9°C and average relative humidity was 44 ± 14% (mean ± SD). Feedline soakers complementing KK systems for 24 h/d decreased the mean CBT of lactating dairy cows compared with KK systems alone (38.80 vs. 38.98 ± 0.061°C, respectively). A significant treatment by time interaction was found. The greatest treatment effects occurred at 2100 h; treatment means at this time were 39.26 and 38.85 ± 0.085°C for OFF24 and ON24 treatments, respectively. In experiment 2, average ambient temperature was 35 ± 1.5°C and average relative humidity was 33 ± 16%. Feedline soakers running for 12 h/d significantly decreased the mean 24-h CBT from 39.16 to 38.99 ± 0.084°C. Treatment by time interaction was also significant; the greatest treatment effects occurred at 1500 h, when ON12 reduced CBT from 39.38 to 38.81 ± 0.088°C. These results demonstrate that complementing the KK system with feedline soakers decreased the CBT of dairy cows housed in desert environments. However, the combined systems were not sufficient to lower CBT to normal temperatures in this extreme environment. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Granular C3 Dermatosis.

PubMed

Hashimoto, Takashi; Tsuruta, Daisuke; Yasukochi, Atsushi; Imanishi, Hisayoshi; Sekine, Hideharu; Fujita, Teizo; Wanibuchi, Hideki; Gi, Min; Kárpáti, Sarolta; Sitaru, Cassian; Zone, John J; Endo, Daisuke; Abe, Shinichi; Nishino, Tomoya; Koji, Takehiko; Ishii, Norito

2016-08-23

There has been no previous systematic study of bullous skin diseases with granular basement membrane zone deposition exclusively of C3. In this study we collected 20 such patients, none of whom showed cutaneous vasculitis histopathologically. Oral dapsone and topical steroids were effective. Various serological tests detected no autoantibodies or autoantigens. Direct immunofluorescence for various complement components revealed deposition only of C3 and C5-C9, indicating that no known complement pathways were involved. Studies of in situ hybridization and micro-dissection with quantitative RT-PCR revealed a slight reduction in expression of C3 in patient epidermis. These patients may represent a new disease entity, for which we propose the term "granular C3 dermatosis". The mechanism for granular C3 deposition in these patients is unknown, but it is possible that the condition is caused by autoantibodies to skin or aberrant C3 expression in epidermal keratinocytes.

Expression of recombinant CD59 with an N-terminal peptide epitope facilitates analysis of residues contributing to its complement-inhibitory function.

PubMed

Zhou, Q; Zhao, J; Hüsler, T; Sims, P J

1996-10-01

CD59 is a plasma membrane-anchored glycoprotein that serves to protect human cells from lysis by the C5b-9 complex of complement. The immunodominant epitopes of CD59 are known to be sensitive to disruption of native tertiary structure, complicating immunological measurement of expressed mutant constructs for structure function analysis. In order to quantify cell-surface expression of wild-type and mutant forms of this complement inhibitor, independent of CD59 antigen, an 11-residue peptide (TAG) recognized by monoclonal antibody (mAb) 9E10 was inserted before the N-terminal codon (L1) of mature CD59, in a pcDNA3 expression plasmid. SV-T2 cells were transfected with this plasmid, yielding cell lines expressing 0 to > 10(5) CD59/cell. The TAG-CD59 fusion protein was confirmed to be GPI-anchored, N-glycosylated and showed identical complement-inhibitory function to wild-type CD59, lacking the TAG peptide sequence. Using this construct, the contribution of each of four surface-localized aromatic residues (4Y, 47F, 61Y, and 62Y) to CD59's complement-inhibitory function was examined. These assays revealed normal surface expression with complete loss of complement-inhibitory function in the 4Y --> S, 47F --> G and 61Y --> S mutants. By contrast, 62Y --> S mutants retained approximately 40% of function of wild-type CD59. These studies confirmed the utility of the TAG-CD59 construct for quantifying CD59 surface expression and activity, and implicate surface aromatic residues 4Y, 47F, 61Y and 62Y as essential to maintenance of CD59's normal complement-regulatory function.

Angiogenic factor imbalance precedes complement deposition in placentae of the BPH/5 model of preeclampsia.

PubMed

Sones, Jennifer L; Merriam, Audrey A; Seffens, Angelina; Brown-Grant, Dex-Ann; Butler, Scott D; Zhao, Anna M; Xu, Xinjing; Shawber, Carrie J; Grenier, Jennifer K; Douglas, Nataki C

2018-05-01

Preeclampsia (PE), a hypertensive disorder of pregnancy, is a leading cause of maternal and fetal morbidity and mortality. Although the etiology is unknown, PE is thought to be caused by defective implantation and decidualization in pregnancy. Pregnant blood pressure high (BPH)/5 mice spontaneously develop placentopathies and maternal features of human PE. We hypothesized that BPH/5 implantation sites have transcriptomic alterations. Next-generation RNA sequencing of implantation sites at peak decidualization, embryonic day (E)7.5, revealed complement gene up-regulation in BPH/5 vs. controls. In BPH/5, expression of complement factor 3 was increased around the decidual vasculature of E7.5 implantation sites and in the trophoblast giant cell layer of E10.5 placentae. Altered expression of VEGF pathway genes in E5.5 BPH/5 implantation sites preceded complement dysregulation, which correlated with abnormal vasculature and increased placental growth factor mRNA and VEGF 164 expression at E7.5. By E10.5, proangiogenic genes were down-regulated, whereas antiangiogenic sFlt-1 was up-regulated in BPH/5 placentae. We found that early local misexpression of VEGF genes and abnormal decidual vasculature preceded sFlt-1 overexpression and increased complement deposition in BPH/5 placentae. Our findings suggest that abnormal decidual angiogenesis precedes complement activation, which in turn contributes to the aberrant trophoblast invasion and poor placentation that underlie PE.-Sones, J. L., Merriam, A. A., Seffens, A., Brown-Grant, D.-A., Butler, S. D., Zhao, A. M., Xu, X., Shawber, C. J., Grenier, J. K., Douglas, N. C. Angiogenic factor imbalance precedes complement deposition in placentae of the BPH/5 model of preeclampsia.

Detection of plum pox potyviral protein-protein interactions in planta using an optimized mRFP-based bimolecular fluorescence complementation system.

PubMed

Zilian, Eva; Maiss, Edgar

2011-12-01

In previous studies, protein interaction maps of different potyviruses have been generated using yeast two-hybrid (YTH) systems, and these maps have demonstrated a high diversity of interactions of potyviral proteins. Using an optimized bimolecular fluorescence complementation (BiFC) system, a complete interaction matrix for proteins of a potyvirus was developed for the first time under in planta conditions with ten proteins from plum pox virus (PPV). In total, 52 of 100 possible interactions were detected, including the self-interactions of CI, 6K2, VPg, NIa-Pro, NIb and CP, which is more interactions than have ever been detected for any other potyvirus in a YTH approach. Moreover, the BiFC system was shown to be able to localize the protein interactions, which was typified for the protein self-interactions indicated above. Additionally, experiments were carried out with the P3N-PIPO protein, revealing an interaction with CI but not with CP and supporting the involvement of P3N-PIPO in the cell-to-cell movement of potyviruses. No self-interaction of the PPV helper component-proteinase (HC-Pro) was detected using BiFC in planta. Therefore, additional experiments with turnip mosaic virus (TuMV) HC-Pro, PPV_HC-Pro and their mutants were conducted. The self-interaction of TuMV_HCpro, as recently demonstrated, and the self-interaction of the TuMV_ and PPV_HC-Pro mutants were shown by BiFC in planta, indicating that HC-Pro self-interactions may be species-specific. BiFC is a very useful and reliable method for the detection and localization of protein interactions in planta, thus enabling investigations under more natural conditions than studies in yeast cells.

Communicating Zika Risk: Using Metaphor to Increase Perceived Risk Susceptibility.

PubMed

Lu, Hang; Schuldt, Jonathon P

2018-02-27

Effectively communicating the risks associated with emerging zoonotic diseases remains an important challenge. Drawing on research into the psychological effects of metaphoric framing, we explore the conditions under which exposure to the "nation as a body" metaphor influences perceived risk susceptibility, behavioral intentions, and policy support in the context of Zika virus. In a between-subjects experiment, 354 U.S. adults were randomly assigned to one of four experimental conditions as part of a 2 (severity message: high vs. low) × 2 (U.S. framing: metaphoric vs. literal) design. Results revealed an interaction effect such that metaphoric (vs. literal) framing increased perceived risk susceptibility in the high-severity condition only. Further analyses revealed that perceived risk susceptibility and negative affect mediated the path between the two-way interaction and policy support and behavioral intentions regarding Zika prevention. Overall, these findings complement prior work on the influence of metaphoric framing on risk perceptions, while offering practical insights for risk communicators seeking to communicate about Zika and other zoonotic diseases. © 2018 Society for Risk Analysis.

Experiments and Cycling at the LHC Prototype Half-Cell

NASA Astrophysics Data System (ADS)

Saban, R.; Casas-Cubillos, J.; Coull, L.; Cruikshank, P.; Dahlerup-Petersen, K.; Hilbert, B.; Krainz, G.; Kos, N.; Lebrun, P.; Momal, F.; Misiaen, D.; Parma, V.; Poncet, A.; Riddone, G.; Rijllart, A.; Rodriguez-Mateos, F.; Schmidt, R.; Serio, L.; Wallen, E.; van Weelderen, R.; Williams, L. R.

1997-05-01

The first version of the LHC prototype half-cell has been in operation since February 1995. It consists of one quadrupole and three 10-m twin aperture dipole magnets which operate at 1.8 K. This experimental set-up has been used to observe and study phenomena which appear when the systems are assembled in one unit and influence one another. The 18-month long experimental program has validated the cryogenic system and yielded a number of results on cryogenic instrumentation, magnet protection and vacuum in particular under non-standard operating conditions. The program was recently complemented by the cycling experiment: it consisted in powering the magnets following the ramp rates which will be experienced by the magnets during an LHC injection. In order to simulate 10 years of routine operation of LHC, more than 2000 1-hour cycles were performed interleaved with provoked quenches. The objective of this experiment was to reveal eventual flaws in the design of components. The prototype half-cell performed to expectations showing no sign of failure of fatigue of components for more than 2000 cycles until one of the dipoles started exhibiting an erratic quench behavior.

Experience and appreciation

Treesearch

Yi-Fu Tuan

1977-01-01

A young child has keen senses, but his world is not thereby more filled with sensory values than that of an adult. To enjoy the physical environment fully the mere capacity to experience stimuli is not enough; it must be complemented by appreciation, which is an intellectual activity. A young child's experiences of nature are often more intense than those of an...

Induction of suppressor cells in vitro by Candida albicans.

PubMed

Cuff, C F; Rogers, C M; Lamb, B J; Rogers, T J

1986-06-01

Normal splenocytes cultured with Formalin-killed Candida albicans were shown to acquire significant suppressor cell activity in a period of 3 days. These cells were found to suppress both the phytohemagglutinin-induced mitogen response as well as the anti-sheep erythrocyte antibody response. Experiments were carried out to determine the nature of the suppressor cell population. Results showed that these cells were not susceptible to treatment with anti-Thy 1 antibody and complement. Panning experiments showed that the suppressor cells were not plastic-adherent or Mac-1 antigen-positive. The suppressor cells were, however, adherent to anti-mouse immunoglobulin (F(ab')2-fragment)-coated dishes. Additional experiments showed that the suppressor cell activity was susceptible to treatment with monoclonal anti-Lyb 2.1 antibody and complement. These results suggest that the suppressor cell induced in vitro by Candida is a member of the B-lymphocyte lineage.

Intersubjectivity in schizophrenia: life story analysis of three cases

PubMed Central

Irarrázaval, Leonor; Sharim, Dariela

2014-01-01

The processes involved in schizophrenia are approached from a viewpoint of understanding, revealing those social elements susceptible to integration for psychotherapeutic purposes, as a complement to the predominant medical-psychiatric focus. Firstly, the paper describes the patients’ disturbances of self-experience and body alienations manifested in acute phases of schizophrenia. Secondly, the paper examines the patients’ personal biographical milestones and consequently the acute episode is contextualized within the intersubjective scenario in which it manifested itself in each case. Thirdly, the patients’ life stories are analyzed from a clinical psychological perspective, meaningfully connecting symptoms and life-world. Finally, it will be argued that the intersubjective dimension of the patients’ life stories shed light not only on the interpersonal processes involved in schizophrenia but also upon the psychotherapeutic treatment best suited to each individual case. PMID:24575073

Subdiffractional focusing and guiding of polaritonic rays in a natural hyperbolic material

PubMed Central

Dai, S.; Ma, Q.; Andersen, T.; Mcleod, A. S.; Fei, Z.; Liu, M. K.; Wagner, M.; Watanabe, K.; Taniguchi, T.; Thiemens, M.; Keilmann, F.; Jarillo-Herrero, P.; Fogler, M. M.; Basov, D. N.

2015-01-01

Uniaxial materials whose axial and tangential permittivities have opposite signs are referred to as indefinite or hyperbolic media. In such materials, light propagation is unusual leading to novel and often non-intuitive optical phenomena. Here we report infrared nano-imaging experiments demonstrating that crystals of hexagonal boron nitride, a natural mid-infrared hyperbolic material, can act as a ‘hyper-focusing lens' and as a multi-mode waveguide. The lensing is manifested by subdiffractional focusing of phonon–polaritons launched by metallic disks underneath the hexagonal boron nitride crystal. The waveguiding is revealed through the modal analysis of the periodic patterns observed around such launchers and near the sample edges. Our work opens new opportunities for anisotropic layered insulators in infrared nanophotonics complementing and potentially surpassing concurrent artificial hyperbolic materials with lower losses and higher optical localization. PMID:25902364

Bacterial Synthesis of Unusual Sulfonamide and Sulfone Antibiotics by Flavoenzyme-Mediated Sulfur Dioxide Capture.

PubMed

Baunach, Martin; Ding, Ling; Willing, Karsten; Hertweck, Christian

2015-11-02

Sulfa drugs, such as sulfonilamide and dapsone, are classical antibiotics that have been in clinical use worldwide. Despite the relatively simple architectures, practically no natural products are known to feature such aromatic sulfonamide or diarylsulfone substructures. We report the unexpected discovery of three fully unprecedented, sulfonyl-bridged alkaloid dimers (sulfadixiamycins A-C) from recombinant Streptomyces species harboring the entire xiamycin biosynthesis gene cluster. Sulfadixiamycins exhibit moderate antimycobacterial activities and potent antibiotic activities even against multidrug-resistant bacteria. Gene inactivation, complementation, and biotransformation experiments revealed that a flavin-dependent enzyme (XiaH) plays a key role in sulfadixiamycin biosynthesis. XiaH mediates a radical-based, three-component reaction involving two equivalents of xiamycin and sulfur dioxide, which is reminiscent of radical styrene/SO2 copolymerization. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Asymmetric interactions in the adenosine-binding pockets of the MS2 coat protein dimer

PubMed Central

Powell, Amy J; Peabody, David S

2001-01-01

Background The X-ray structure of the MS2 coat protein-operator RNA complex reveals the existence of quasi-synmetric interactions of adenosines -4 and -10 in pockets formed on different subunits of the coat protein dimer. Both pockets utilize the same five amino acid residues, namely Val29, Thr45, Ser47, Thr59, and Lys61. We call these sites the adenosine-binding pockets. Results We present here a heterodimer complementation analysis of the contributions of individual A-pocket amino acids to the binding of A-4 and A-10 in different halves of the dimer. Various substitutions of A-pocket residues were introduced into one half of single-chain coat protein heterodimers where they were tested for their abilities to complement Y85H or T91I substitutions (defects in the A-4 and A-10 half-sites, respectively) present in the other dimer half. Conclusions These experiments provide functional tests of interactions predicted from structural analyses, demonstrating the importance of certain amino acid-nucleotide contacts observed in the crystal structure, and showing that others make little or no contribution to the stability of the complex. In summary, Val29 and Lys61 form important stabilizing interactions with both A-4 and A-10. Meanwhile, Ser47 and Thr59 interact primarily with A-10. The important interactions with Thr45 are restricted to A-4. PMID:11504563

The Toxoplasma gondii cyst wall protein CST1 is critical for cyst wall integrity and promotes bradyzoite persistence

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tomita, Tadakimi; Bzik, David J.; Ma, Yan Fen

2013-12-26

Toxoplasma gondii infects up to one third of the world’s population. A key to the success of T.gondii is its ability to persist for the life of its host as bradyzoites within tissue cysts. The glycosylated cyst wall is the key structural feature that facilitates persistence and oral transmission of this parasite. We have identified CST1 (TGME49_064660) as a 250 kDa SRS (SAG1 related sequence) domain protein with a large mucin-like domain. CST1 is responsible for the Dolichos biflorus Agglutinin (DBA) lectin binding characteristic of T. gondii cysts. Deletion of CST1 results in a fragile brain cyst phenotype revealed bymore » a thinning and disruption of the underlying region of the cyst wall. These defects are reversed by complementation of CST1. Additional complementation experiments demonstrate that the CST1-mucin domain is necessary for the formation of a normal cyst wall structure, the ability of the cyst to resist mechanical stress and binding of DBA to the cyst wall. RNA-seq transcriptome analysis demonstrated dysregulation of bradyzoite genes within the various cst1 mutants. These results indicate that CST1 functions as a key structural component that reinforces the cyst wall structure and confers essential sturdiness to the T. gondii tissue cyst.« less

Biosynthetic Investigations of Lactonamycin and Lactonamycin Z: Cloning of the Biosynthetic Gene Clusters and Discovery of an Unusual Starter Unit▿ †

PubMed Central

Zhang, Xiujun; Alemany, Lawrence B.; Fiedler, Hans-Peter; Goodfellow, Michael; Parry, Ronald J.

2008-01-01

The antibiotics lactonamycin and lactonamycin Z provide attractive leads for antibacterial drug development. Both antibiotics contain a novel aglycone core called lactonamycinone. To gain insight into lactonamycinone biosynthesis, cloning and precursor incorporation experiments were undertaken. The lactonamycin gene cluster was initially cloned from Streptomyces rishiriensis. Sequencing of ca. 61 kb of S. rishiriensis DNA revealed the presence of 57 open reading frames. These included genes coding for the biosynthesis of l-rhodinose, the sugar found in lactonamycin, and genes similar to those in the tetracenomycin biosynthetic gene cluster. Since lactonamycin production by S. rishiriensis could not be sustained, additional proof for the identity of the S. rishiriensis cluster was obtained by cloning the lactonamycin Z gene cluster from Streptomyces sanglieri. Partial sequencing of the S. sanglieri cluster revealed 15 genes that exhibited a very high degree of similarity to genes within the lactonamycin cluster, as well as an identical organization. Double-crossover disruption of one gene in the S. sanglieri cluster abolished lactonamycin Z production, and production was restored by complementation. These results confirm the identity of the genetic locus cloned from S. sanglieri and indicate that the highly similar locus in S. rishiriensis encodes lactonamycin biosynthetic genes. Precursor incorporation experiments with S. sanglieri revealed that lactonamycinone is biosynthesized in an unusual manner whereby glycine or a glycine derivative serves as a starter unit that is extended by nine acetate units. Analysis of the gene clusters and of the precursor incorporation data suggested a hypothetical scheme for lactonamycinone biosynthesis. PMID:18070976

Role of capsule and suilysin in mucosal infection of complement-deficient mice with Streptococcus suis.

PubMed

Seitz, Maren; Beineke, Andreas; Singpiel, Alena; Willenborg, Jörg; Dutow, Pavel; Goethe, Ralph; Valentin-Weigand, Peter; Klos, Andreas; Baums, Christoph G

2014-06-01

Virulent Streptococcus suis serotype 2 strains are invasive extracellular bacteria causing septicemia and meningitis in piglets and humans. One objective of this study was to elucidate the function of complement in innate immune defense against S. suis. Experimental infection of wild-type (WT) and C3(-/-) mice demonstrated for the first time that the complement system protects naive mice against invasive mucosal S. suis infection. S. suis WT but not an unencapsulated mutant caused mortality associated with meningitis and other pathologies in C3(-/-) mice. The capsule contributed also substantially to colonization of the upper respiratory tract. Experimental infection of C3(-/-) mice with a suilysin mutant indicated that suilysin expression facilitated an early disease onset and the pathogenesis of meningitis. Flow cytometric analysis revealed C3 antigen deposition on the surface of ca. 40% of S. suis WT bacteria after opsonization with naive WT mouse serum, although to a significantly lower intensity than on the unencapsulated mutant. Ex vivo multiplication in murine WT and C3(-/-) blood depended on capsule but not suilysin expression. Interestingly, S. suis invasion of inner organs was also detectable in C5aR(-/-) mice, suggesting that chemotaxis and activation of immune cells via the anaphylatoxin receptor C5aR is, in addition to opsonization, a further important function of the complement system in defense against mucosal S. suis infection. In conclusion, we unequivocally demonstrate here the importance of complement against mucosal S. suis serotype 2 infection and that the capsule of this pathogen is also involved in escape from complement-independent immunity.

Complement Protein C1q Modulates Neurite Outgrowth In Vitro and Spinal Cord Axon Regeneration In Vivo

PubMed Central

Peterson, Sheri L.; Nguyen, Hal X.; Mendez, Oscar A.

2015-01-01

Traumatic injury to CNS fiber tracts is accompanied by failure of severed axons to regenerate and results in lifelong functional deficits. The inflammatory response to CNS trauma is mediated by a diverse set of cells and proteins with varied, overlapping, and opposing effects on histological and behavioral recovery. Importantly, the contribution of individual inflammatory complement proteins to spinal cord injury (SCI) pathology is not well understood. Although the presence of complement components increases after SCI in association with axons and myelin, it is unknown whether complement proteins affect axon growth or regeneration. We report a novel role for complement C1q in neurite outgrowth in vitro and axon regrowth after SCI. In culture, C1q increased neurite length on myelin. Protein and molecular assays revealed that C1q interacts directly with myelin associated glycoprotein (MAG) in myelin, resulting in reduced activation of growth inhibitory signaling in neurons. In agreement with a C1q-outgrowth-enhancing mechanism in which C1q binding to MAG reduces MAG signaling to neurons, complement C1q blocked both the growth inhibitory and repulsive turning effects of MAG in vitro. Furthermore, C1q KO mice demonstrated increased sensory axon turning within the spinal cord lesion after SCI with peripheral conditioning injury, consistent with C1q-mediated neutralization of MAG. Finally, we present data that extend the role for C1q in axon growth and guidance to include the sprouting patterns of descending corticospinal tract axons into spinal gray matter after dorsal column transection SCI. PMID:25762679

Climate Warming and Soil Carbon in Tropical Forests: Insights from an Elevation Gradient in the Peruvian Andes

PubMed Central

Nottingham, Andrew T.; Whitaker, Jeanette; Turner, Benjamin L.; Salinas, Norma; Zimmermann, Michael; Malhi, Yadvinder; Meir, Patrick

2015-01-01

The temperature sensitivity of soil organic matter (SOM) decomposition in tropical forests will influence future climate. Studies of a 3.5-kilometer elevation gradient in the Peruvian Andes, including short-term translocation experiments and the examination of the long-term adaptation of biota to local thermal and edaphic conditions, have revealed several factors that may regulate this sensitivity. Collectively this work suggests that, in the absence of a moisture constraint, the temperature sensitivity of decomposition is regulated by the chemical composition of plant debris (litter) and both the physical and chemical composition of preexisting SOM: higher temperature sensitivities are found in litter or SOM that is more chemically complex and in SOM that is less occluded within aggregates. In addition, the temperature sensitivity of SOM in tropical montane forests may be larger than previously recognized because of the presence of “cold-adapted” and nitrogen-limited microbial decomposers and the possible future alterations in plant and microbial communities associated with warming. Studies along elevation transects, such as those reviewed here, can reveal factors that will regulate the temperature sensitivity of SOM. They can also complement and guide in situ soil-warming experiments, which will be needed to understand how this vulnerability to temperature may be mediated by altered plant productivity under future climatic change. PMID:26955086

The Role of Complement in Cnidarian-Dinoflagellate Symbiosis and Immune Challenge in the Sea Anemone Aiptasia pallida

PubMed Central

Poole, Angela Z.; Kitchen, Sheila A.; Weis, Virginia M.

2016-01-01

The complement system is an innate immune pathway that in vertebrates, is responsible for initial recognition and ultimately phagocytosis and destruction of microbes. Several complement molecules including C3, Factor B, and mannose binding lectin associated serine proteases (MASP) have been characterized in invertebrates and while most studies have focused on their conserved role in defense against pathogens, little is known about their role in managing beneficial microbes. The purpose of this study was to (1) characterize complement pathway genes in the symbiotic sea anemone Aiptasia pallida, (2) investigate the evolution of complement genes in invertebrates, and (3) examine the potential dual role of complement genes Factor B and MASP in the onset and maintenance of cnidarian-dinoflagellate symbiosis and immune challenge using qPCR based studies. The results demonstrate that A. pallida has multiple Factor B genes (Ap_Bf-1, Ap_Bf-2a, and Ap_Bf-2b) and one MASP gene (Ap_MASP). Phylogenetic analysis indicates that the evolutionary history of complement genes is complex, and there have been many gene duplications or gene loss events, even within members of the same phylum. Gene expression analyses revealed a potential role for complement in both onset and maintenance of cnidarian-dinoflagellate symbiosis and immune challenge. Specifically, Ap_Bf-1 and Ap_MASP are significantly upregulated in the light at the onset of symbiosis and in response to challenge with the pathogen Serratia marcescens suggesting that they play a role in the initial recognition of both beneficial and harmful microbes. Ap_Bf-2b in contrast, was generally downregulated during the onset and maintenance of symbiosis and in response to challenge with S. marcescens. Therefore, the exact role of Ap_Bf-2b in response to microbes remains unclear, but the results suggest that the presence of microbes leads to repressed expression. Together, these results indicate functional divergence between Ap_Bf-1 and Ap_Bf-2b, and that Ap_Bf-1 and Ap_MASP may be functioning together in an ancestral hybrid of the lectin and alternative complement pathways. Overall, this study provides information on the role of the complement system in a basal metazoan and its role in host-microbe interactions. PMID:27148208

The Role of Complement in Cnidarian-Dinoflagellate Symbiosis and Immune Challenge in the Sea Anemone Aiptasia pallida.

PubMed

Poole, Angela Z; Kitchen, Sheila A; Weis, Virginia M

2016-01-01

The complement system is an innate immune pathway that in vertebrates, is responsible for initial recognition and ultimately phagocytosis and destruction of microbes. Several complement molecules including C3, Factor B, and mannose binding lectin associated serine proteases (MASP) have been characterized in invertebrates and while most studies have focused on their conserved role in defense against pathogens, little is known about their role in managing beneficial microbes. The purpose of this study was to (1) characterize complement pathway genes in the symbiotic sea anemone Aiptasia pallida, (2) investigate the evolution of complement genes in invertebrates, and (3) examine the potential dual role of complement genes Factor B and MASP in the onset and maintenance of cnidarian-dinoflagellate symbiosis and immune challenge using qPCR based studies. The results demonstrate that A. pallida has multiple Factor B genes (Ap_Bf-1, Ap_Bf-2a, and Ap_Bf-2b) and one MASP gene (Ap_MASP). Phylogenetic analysis indicates that the evolutionary history of complement genes is complex, and there have been many gene duplications or gene loss events, even within members of the same phylum. Gene expression analyses revealed a potential role for complement in both onset and maintenance of cnidarian-dinoflagellate symbiosis and immune challenge. Specifically, Ap_Bf-1 and Ap_MASP are significantly upregulated in the light at the onset of symbiosis and in response to challenge with the pathogen Serratia marcescens suggesting that they play a role in the initial recognition of both beneficial and harmful microbes. Ap_Bf-2b in contrast, was generally downregulated during the onset and maintenance of symbiosis and in response to challenge with S. marcescens. Therefore, the exact role of Ap_Bf-2b in response to microbes remains unclear, but the results suggest that the presence of microbes leads to repressed expression. Together, these results indicate functional divergence between Ap_Bf-1 and Ap_Bf-2b, and that Ap_Bf-1 and Ap_MASP may be functioning together in an ancestral hybrid of the lectin and alternative complement pathways. Overall, this study provides information on the role of the complement system in a basal metazoan and its role in host-microbe interactions.

In vitro C3 mRNA expression in Pemphigus vulgaris: complement activation is increased by IL-1alpha and TNF-alpha.

PubMed

Feliciani, C; Toto, P; Amerio, P

1999-01-01

Pemphigus vulgaris (PV) is a potentially life-threatening disease, characterized immunohistologically by IgG deposits and complement activation on the surface of keratinocytes. Complement activation has been implicated in the pathogenesis with C3 deposits in about 90% of patients. In order to further elucidate the role of complement in PV and to define which cytokines play a role in C3 mRNA expression, we performed an in vitro study in human keratinocytes. Normal human epidermal keratinocytes (NHuK) were incubated with PV serum and C3 mRNA was measured. We previously had shown that IL-1alpha and TNF-alpha are expressed in PV in vivo and in vitro. Since cytokines are able to modulate complement activation, mRNA expression was evaluated in a similar experiment after pretreatment using antibodies against IL-1alpha and TNF-alpha. Incubation of NHuK with PV sera caused their detachment from the plates after 20-30 minutes with a complete acantholysis within 12 hours. An early C3 mRNA expression was seen after 30 minutes with a peak level after 1 hour. Blocking studies, using antibodies against human IL-1alpha and TNF-alpha in NHuK together with PV-IgG, showed reduction of in vitro induced acantholysis and inhibition of C3 mRNA expression. This study supports the hypothesis that complement C3 is important in PV acantholysis and that complement activation is increased by IL-1alpha and TNF-alpha.

Human Factors Experiments for Data Link : Interim Report No. 5

DOT National Transportation Integrated Search

1975-02-01

One and two-man crews of general aviation pilots and two-man crews of FAA/NAFEC test pilots made a series of simulated flights in a GAT-2 simulator to evaluate various complements of I/O equipment for Data Link. In the earlier experiments in the seri...

Mission Mathematics II: Prekindergarten-Grade 2 (with CD-ROM)

ERIC Educational Resources Information Center

Hynes, Ellen Mary, Ed.; Blair, Catherine, Ed.

2005-01-01

Get students into math using outer space! Mission Mathematics translates the NASA experience into language and experiences appropriate for young learners, and provides teachers with mathematics activities that complement many of the available NASA resources for students and educators. In these motivating investigations, young children engage in…

A Classroom-Field Model of Inter-Ethnic Communication.

ERIC Educational Resources Information Center

Nielsen, Keith E.

The BLBC (bilingual-bicultural) model of inter-ethnic communication is an effective method for bridging the instructional "gap" between classroom education and field experiences. These two learning experiences are distinct; yet each should complement the other. The BLBC model of inter-ethnic communication attempts to interface the student's…

Synthesis of Ethyl Nalidixate: A Medicinal Chemistry Experiment

ERIC Educational Resources Information Center

Leslie, Ray; Leeb, Elaine; Smith, Robert B.

2012-01-01

A series of laboratory experiments that complement a medicinal chemistry lecture course in drug design and development have been developed. The synthesis of ethyl nalidixate covers three separate experimental procedures, all of which can be completed in three, standard three-hour lab classes and incorporate aspects of green chemistry such as…

Purity homophily in social networks.

PubMed

Dehghani, Morteza; Johnson, Kate; Hoover, Joe; Sagi, Eyal; Garten, Justin; Parmar, Niki Jitendra; Vaisey, Stephen; Iliev, Rumen; Graham, Jesse

2016-03-01

Does sharing moral values encourage people to connect and form communities? The importance of moral homophily (love of same) has been recognized by social scientists, but the types of moral similarities that drive this phenomenon are still unknown. Using both large-scale, observational social-media analyses and behavioral lab experiments, the authors investigated which types of moral similarities influence tie formations. Analysis of a corpus of over 700,000 tweets revealed that the distance between 2 people in a social-network can be predicted based on differences in the moral purity content-but not other moral content-of their messages. The authors replicated this finding by experimentally manipulating perceived moral difference (Study 2) and similarity (Study 3) in the lab and demonstrating that purity differences play a significant role in social distancing. These results indicate that social network processes reflect moral selection, and both online and offline differences in moral purity concerns are particularly predictive of social distance. This research is an attempt to study morality indirectly using an observational big-data study complemented with 2 confirmatory behavioral experiments carried out using traditional social-psychology methodology. (c) 2016 APA, all rights reserved).

O1.6. INCREASED COMPLEMENT FACTORS C3 AND C4 IN SCHIZOPHRENIA AND THE EARLY STAGES OF PSYCHOSIS: IMPLICATIONS FOR CLINICAL SYMPTOMATOLOGY AND CORTICAL THICKNESS

PubMed Central

Cropley, Vanessa; Laskaris, Liliana; Zalesky, Andrew; Weickert, Cynthia Shannon; Biase, Maria Di; Chana, Gursharan; Baune, Bernhard; Bousman, Chad; Nelson, Barnaby; McGorry, Patrick D; Everall, Ian; Pantelis, Christos

2018-01-01

Abstract Background The complement system - a key component of the innate immune system, has been proposed to contribute to the pathogenesis of schizophrenia. Recently, complement C4 was associated with increased risk of schizophrenia, and in a mouse model, developmentally-timed synaptic pruning. These observations have led to proposals that abnormal activation of the complement system might contribute to the development of schizophrenia by disrupting synaptic pruning during key developmental periods. However, despite renewed interest in the complement system in schizophrenia it remains unclear whether peripheral complement levels differ in cases compared to controls, change over the course of illness and whether they are associated with current symptomatology and brain cortical thickness. This study aimed to: i) investigate whether peripheral complement protein levels are altered at different stages of illness, and ii) identify patterns among complement protein levels that predict clinical symptoms and grey matter thickness across the cortex. Methods Complement factors C1q, C3 and C4 were quantified in 183 participants [n=83 Healthy Controls (HC), n=10 Ultra-High Risk (UHR) for psychosis, n=40 First Episode Psychosis (FEP), n=50 Chronic schizophrenia] using Multiplex ELISA. Permutation-based t-tests were used to assess between-group differences in complement protein levels at each of the three illness stages, relative to age- and gender-matched healthy controls. Canonical correlation analysis was used to identify patterns of complement protein levels that correlated with clinical symptoms and regional thickness across the cortex. Results C3 and C4 were significantly increased in FEP and UHR patients, whereas only C4 was significantly increased in chronic patients. A molecular pattern of increased C4 and decreased C3 was associated with positive and negative symptom severity in the pooled patient sample. Increased C4 levels alone, or decreased C3 levels alone, did not correlate with symptom severity as strongly as the pattern of increased C4 in combination with decreased C3. Preliminary canonical correlation analyses revealed that, in healthy controls, a molecular pattern characterised by increased C3 and decreased C4 was associated with relatively thinner paracentral, inferior parietal and inferior temporal cortices, but relatively thicker insular, in the left hemisphere. In the pooled patient group, a trend for increased C3 in combination with decreased C1q was associated with relatively thinner left lateral occipital cortex and pars orbitalis but relatively thicker pars opercularis and precuneus. Discussion Our findings indicate that peripheral complement concentration is particularly increased early and preceding psychosis and its imbalance may be associated with symptom severity and variation in regional grey matter thickness across the cortex.

Acquisition of Complement Inhibitor Serine Protease Factor I and Its Cofactors C4b-Binding Protein and Factor H by Prevotella intermedia

PubMed Central

Malm, Sven; Jusko, Monika; Eick, Sigrun; Potempa, Jan; Riesbeck, Kristian; Blom, Anna M.

2012-01-01

Infection with the Gram-negative pathogen Prevotella intermedia gives rise to periodontitis and a growing number of studies implies an association of P. intermedia with rheumatoid arthritis. The serine protease Factor I (FI) is the central inhibitor of complement degrading complement components C3b and C4b in the presence of cofactors such as C4b-binding protein (C4BP) and Factor H (FH). Yet, the significance of complement inhibitor acquisition in P. intermedia infection and FI binding by Gram-negative pathogens has not been addressed. Here we show that P. intermedia isolates bound purified FI as well as FI directly from heat-inactivated human serum. FI bound to bacteria retained its serine protease activity as shown in degradation experiments with 125I-labeled C4b. Since FI requires cofactors for its activity we also investigated the binding of purified cofactors C4BP and FH and found acquisition of both proteins, which retained their activity in FI mediated degradation of C3b and C4b. We propose that FI binding by P. intermedia represents a new mechanism contributing to complement evasion by a Gram-negative bacterial pathogen associated with chronic diseases. PMID:22514678

Acquisition of complement inhibitor serine protease factor I and its cofactors C4b-binding protein and factor H by Prevotella intermedia.

PubMed

Malm, Sven; Jusko, Monika; Eick, Sigrun; Potempa, Jan; Riesbeck, Kristian; Blom, Anna M

2012-01-01

Infection with the Gram-negative pathogen Prevotella intermedia gives rise to periodontitis and a growing number of studies implies an association of P. intermedia with rheumatoid arthritis. The serine protease Factor I (FI) is the central inhibitor of complement degrading complement components C3b and C4b in the presence of cofactors such as C4b-binding protein (C4BP) and Factor H (FH). Yet, the significance of complement inhibitor acquisition in P. intermedia infection and FI binding by Gram-negative pathogens has not been addressed. Here we show that P. intermedia isolates bound purified FI as well as FI directly from heat-inactivated human serum. FI bound to bacteria retained its serine protease activity as shown in degradation experiments with (125)I-labeled C4b. Since FI requires cofactors for its activity we also investigated the binding of purified cofactors C4BP and FH and found acquisition of both proteins, which retained their activity in FI mediated degradation of C3b and C4b. We propose that FI binding by P. intermedia represents a new mechanism contributing to complement evasion by a Gram-negative bacterial pathogen associated with chronic diseases.

Evaluation of Pasteurella multocida serotype B:2 resistance to immune serum and complement system

PubMed Central

Ataei Kachooei, Saeed; Ranjbar, Mohammad Mehdi; Ataei Kachooei, Saba

2017-01-01

Members of gram-negative bacteria family Pasteurellaceae, include a large number of important economically human and veterinary pathogens. Organisms belonging to the family can colonize in mucosal surfaces of the respiratory, alimentary, genital tracts and cause diseases in various mammals, birds, and reptiles. Hemorrhagic septicemia is an acute disease of cattle and buffaloes in tropical countries caused by Pasteurella multocida serotype B:2. In the present study, the possible bactericidal activity of immune calf sera in the presence and absence of complement system was investigated. The results showed that P. multocida B:2 is highly resistant to positive serum, containing high levels of IgG and IgM obtained from calves after vaccination, and complement activity in normal fresh calf serum. This organism also grew rapidly in the normal fresh calf serum and the mixture of positive serum as well as normal fresh calf serum. As a control test an E. coli strain was subjected to the same experiment and found completely sensitive to the bactericidal activity of complement in calf and guinea pig fresh sera. Results were indicative of the presence of inhibitory mechanism(s) in P. multocida B:2 against bactericidal activity of immune calf serum and complement system. PMID:29085604

Determinism and Contingency Shape Metabolic Complementation in an Endosymbiotic Consortium

PubMed Central

Ponce-de-Leon, Miguel; Tamarit, Daniel; Calle-Espinosa, Jorge; Mori, Matteo; Latorre, Amparo; Montero, Francisco; Pereto, Juli

2017-01-01

Bacterial endosymbionts and their insect hosts establish an intimate metabolic relationship. Bacteria offer a variety of essential nutrients to their hosts, whereas insect cells provide the necessary sources of matter and energy to their tiny metabolic allies. These nutritional complementations sustain themselves on a diversity of metabolite exchanges between the cell host and the reduced yet highly specialized bacterial metabolism—which, for instance, overproduces a small set of essential amino acids and vitamins. A well-known case of metabolic complementation is provided by the cedar aphid Cinara cedri that harbors two co-primary endosymbionts, Buchnera aphidicola BCc and Ca. Serratia symbiotica SCc, and in which some metabolic pathways are partitioned between different partners. Here we present a genome-scale metabolic network (GEM) for the bacterial consortium from the cedar aphid iBSCc. The analysis of this GEM allows us the confirmation of cases of metabolic complementation previously described by genome analysis (i.e., tryptophan and biotin biosynthesis) and the redefinition of an event of metabolic pathway sharing between the two endosymbionts, namely the biosynthesis of tetrahydrofolate. In silico knock-out experiments with iBSCc showed that the consortium metabolism is a highly integrated yet fragile network. We also have explored the evolutionary pathways leading to the emergence of metabolic complementation between reduced metabolisms starting from individual, complete networks. Our results suggest that, during the establishment of metabolic complementation in endosymbionts, adaptive evolution is significant in the case of tryptophan biosynthesis, whereas vitamin production pathways seem to adopt suboptimal solutions. PMID:29213256

Determinism and Contingency Shape Metabolic Complementation in an Endosymbiotic Consortium.

PubMed

Ponce-de-Leon, Miguel; Tamarit, Daniel; Calle-Espinosa, Jorge; Mori, Matteo; Latorre, Amparo; Montero, Francisco; Pereto, Juli

2017-01-01

Bacterial endosymbionts and their insect hosts establish an intimate metabolic relationship. Bacteria offer a variety of essential nutrients to their hosts, whereas insect cells provide the necessary sources of matter and energy to their tiny metabolic allies. These nutritional complementations sustain themselves on a diversity of metabolite exchanges between the cell host and the reduced yet highly specialized bacterial metabolism-which, for instance, overproduces a small set of essential amino acids and vitamins. A well-known case of metabolic complementation is provided by the cedar aphid Cinara cedri that harbors two co-primary endosymbionts, Buchnera aphidicola BCc and Ca . Serratia symbiotica SCc, and in which some metabolic pathways are partitioned between different partners. Here we present a genome-scale metabolic network (GEM) for the bacterial consortium from the cedar aphid i BSCc. The analysis of this GEM allows us the confirmation of cases of metabolic complementation previously described by genome analysis (i.e., tryptophan and biotin biosynthesis) and the redefinition of an event of metabolic pathway sharing between the two endosymbionts, namely the biosynthesis of tetrahydrofolate. In silico knock-out experiments with i BSCc showed that the consortium metabolism is a highly integrated yet fragile network. We also have explored the evolutionary pathways leading to the emergence of metabolic complementation between reduced metabolisms starting from individual, complete networks. Our results suggest that, during the establishment of metabolic complementation in endosymbionts, adaptive evolution is significant in the case of tryptophan biosynthesis, whereas vitamin production pathways seem to adopt suboptimal solutions.

Complement Activation in Relation to Capillary Leakage in Children with Septic Shock and Purpura

PubMed Central

Hazelzet, Jan A.; de Groot, Ronald; van Mierlo, Gerard; Joosten, Koen F. M.; van der Voort, Edwin; Eerenberg, Anke; Suur, Marja H.; Hop, Wim C. J.; Hack, C. Erik

1998-01-01

To assess the relationship between capillary leakage and inflammatory mediators during sepsis, blood samples were taken on hospital admission, as well as 24 and 72 h later, from 52 children (median age, 3.3 years) with severe meningococcal sepsis, of whom 38 survived and 14 died. Parameters related to cytokines (interleukin 6 [IL-6] IL-8, plasma phospholipase A2, and C-reactive protein [CRP]), to neutrophil degranulation (elastase and lactoferrin), to complement activation (C3a, C3b/c, C4b/c, and C3- and C4-CRP complexes), and to complement regulation (functional and inactivated C1 inhibitor and C4BP) were determined. The degree of capillary leakage was derived from the amount of plasma infused and the severity of disease by assessing the pediatric risk of mortality (PRISM) score. Levels of IL-6, IL-8, C3b/c, C3-CRP complexes, and C4BP on admission, adjusted for the duration of skin lesions, were significantly different in survivors and nonsurvivors (C3b/c levels were on average 2.2 times higher in nonsurvivors, and C3-CRP levels were 1.9 times higher in survivors). Mortality was independently related to the levels of C3b/c and C3-CRP complexes. In agreement with this, levels of complement activation products correlated well with the PRISM score or capillary leakage. Thus, these data show that complement activation in patients with severe meningococcal sepsis is associated with a poor outcome and a more severe disease course. Further studies should reveal whether complement activation may be a target for therapeutical intervention in this disease. PMID:9784543

Role of Capsule and Suilysin in Mucosal Infection of Complement-Deficient Mice with Streptococcus suis

PubMed Central

Seitz, Maren; Beineke, Andreas; Singpiel, Alena; Willenborg, Jörg; Dutow, Pavel; Goethe, Ralph; Valentin-Weigand, Peter; Klos, Andreas

2014-01-01

Virulent Streptococcus suis serotype 2 strains are invasive extracellular bacteria causing septicemia and meningitis in piglets and humans. One objective of this study was to elucidate the function of complement in innate immune defense against S. suis. Experimental infection of wild-type (WT) and C3−/− mice demonstrated for the first time that the complement system protects naive mice against invasive mucosal S. suis infection. S. suis WT but not an unencapsulated mutant caused mortality associated with meningitis and other pathologies in C3−/− mice. The capsule contributed also substantially to colonization of the upper respiratory tract. Experimental infection of C3−/− mice with a suilysin mutant indicated that suilysin expression facilitated an early disease onset and the pathogenesis of meningitis. Flow cytometric analysis revealed C3 antigen deposition on the surface of ca. 40% of S. suis WT bacteria after opsonization with naive WT mouse serum, although to a significantly lower intensity than on the unencapsulated mutant. Ex vivo multiplication in murine WT and C3−/− blood depended on capsule but not suilysin expression. Interestingly, S. suis invasion of inner organs was also detectable in C5aR−/− mice, suggesting that chemotaxis and activation of immune cells via the anaphylatoxin receptor C5aR is, in addition to opsonization, a further important function of the complement system in defense against mucosal S. suis infection. In conclusion, we unequivocally demonstrate here the importance of complement against mucosal S. suis serotype 2 infection and that the capsule of this pathogen is also involved in escape from complement-independent immunity. PMID:24686060

Staphylococcus aureus SdrE captures complement factor H's C-terminus via a novel ‘close, dock, lock and latch' mechanism for complement evasion

PubMed Central

Zhang, Yingjie; Wu, Minhao; Hang, Tianrong; Wang, Chengliang; Yang, Ye; Pan, Weimin; Zang, Jianye

2017-01-01

Complement factor H (CFH) is a soluble complement regulatory protein essential for the down-regulation of the alternative pathway on interaction with specific markers on the host cell surface. It recognizes the complement component 3b (C3b) and 3d (C3d) fragments in addition to self cell markers (i.e. glycosaminoglycans, sialic acid) to distinguish host cells that deserve protection from pathogens that should be eliminated. The Staphylococcus aureus surface protein serine–aspartate repeat protein E (SdrE) was previously reported to bind human CFH as an immune-evasion tactic. However, the molecular mechanism underlying SdrE–CFH-mediated immune evasion remains unknown. In the present study, we identified a novel region at CFH's C-terminus (CFH1206–1226), which binds SdrE N2 and N3 domains (SdrEN2N3) with high affinity, and determined the crystal structures of apo-SdrEN2N3 and the SdrEN2N3–CFH1206–1226 complex. Comparison of the structure of the CFH–SdrE complex with other CFH structures reveals that CFH's C-terminal tail flips from the main body to insert into the ligand-binding groove of SdrE. In addition, SdrEN2N3 adopts a ‘close’ state in the absence of CFH, which undergoes a large conformational change on CFH binding, suggesting a novel ‘close, dock, lock and latch' (CDLL) mechanism for SdrE to recognize its ligand. Our findings imply that SdrE functions as a ‘clamp' to capture CFH's C-terminal tail via a unique CDLL mechanism and sequesters CFH on the surface of S. aureus for complement evasion. PMID:28258151

Staphylococcus aureus SdrE captures complement factor H's C-terminus via a novel 'close, dock, lock and latch' mechanism for complement evasion.

PubMed

Zhang, Yingjie; Wu, Minhao; Hang, Tianrong; Wang, Chengliang; Yang, Ye; Pan, Weimin; Zang, Jianye; Zhang, Min; Zhang, Xuan

2017-05-04

Complement factor H (CFH) is a soluble complement regulatory protein essential for the down-regulation of the alternative pathway on interaction with specific markers on the host cell surface. It recognizes the complement component 3b (C3b) and 3d (C3d) fragments in addition to self cell markers (i.e. glycosaminoglycans, sialic acid) to distinguish host cells that deserve protection from pathogens that should be eliminated. The Staphylococcus aureus surface protein serine-aspartate repeat protein E (SdrE) was previously reported to bind human CFH as an immune-evasion tactic. However, the molecular mechanism underlying SdrE-CFH-mediated immune evasion remains unknown. In the present study, we identified a novel region at CFH's C-terminus (CFH 1206-1226 ), which binds SdrE N2 and N3 domains (SdrE N2N3 ) with high affinity, and determined the crystal structures of apo-SdrE N2N3 and the SdrE N2N3 -CFH 1206-1226 complex. Comparison of the structure of the CFH-SdrE complex with other CFH structures reveals that CFH's C-terminal tail flips from the main body to insert into the ligand-binding groove of SdrE. In addition, SdrE N2N3 adopts a 'close' state in the absence of CFH, which undergoes a large conformational change on CFH binding, suggesting a novel 'close, dock, lock and latch' (CDLL) mechanism for SdrE to recognize its ligand. Our findings imply that SdrE functions as a 'clamp' to capture CFH's C-terminal tail via a unique CDLL mechanism and sequesters CFH on the surface of S. aureus for complement evasion. © 2017 The Author(s).

Complement inhibition decreases early fibrogenic events in the lung of septic baboons.

PubMed

Silasi-Mansat, Robert; Zhu, Hua; Georgescu, Constantin; Popescu, Narcis; Keshari, Ravi S; Peer, Glenn; Lupu, Cristina; Taylor, Fletcher B; Pereira, Heloise Anne; Kinasewitz, Gary; Lambris, John D; Lupu, Florea

2015-11-01

Acute respiratory distress syndrome (ARDS) induced by severe sepsis can trigger persistent inflammation and fibrosis. We have shown that experimental sepsis in baboons recapitulates ARDS progression in humans, including chronic inflammation and long-lasting fibrosis in the lung. Complement activation products may contribute to the fibroproliferative response, suggesting that complement inhibitors are potential therapeutic agents. We have been suggested that treatment of septic baboons with compstatin, a C3 convertase inhibitor protects against ARDS-induced fibroproliferation. Baboons challenged with 10(9) cfu/kg (LD50) live E. coli by intravenous infusion were treated or not with compstatin at the time of challenge or 5 hrs thereafter. Changes in the fibroproliferative response at 24 hrs post-challenge were analysed at both transcript and protein levels. Gene expression analysis showed that sepsis induced fibrotic responses in the lung as early as 24 hrs post-bacterial challenge. Immunochemical and biochemical analysis revealed enhanced collagen synthesis, induction of profibrotic factors and increased cell recruitment and proliferation. Specific inhibition of complement with compstatin down-regulated sepsis-induced fibrosis genes, including transforming growth factor-beta (TGF-β), connective tissue growth factor (CTGF), tissue inhibitor of metalloproteinase 1 (TIMP1), various collagens and chemokines responsible for fibrocyte recruitment (e.g. chemokine (C-C motif) ligand 2 (CCL2) and 12 (CCL12)). Compstatin decreased the accumulation of myofibroblasts and proliferating cells, reduced the production of fibrosis mediators (TGF-β, phospho-Smad-2 and CTGF) and inhibited collagen deposition. Our data demonstrate that complement inhibition effectively attenuates collagen deposition and fibrotic responses in the lung after severe sepsis. Inhibiting complement could prove an attractive strategy for preventing sepsis-induced fibrosis of the lung. © 2015 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Pre-transplant donor HLA-specific antibodies: characteristics causing detrimental effects on survival after lung transplantation.

PubMed

Smith, John D; Ibrahim, Mohamed W; Newell, Helen; Danskine, Anna J; Soresi, Simona; Burke, Margaret M; Rose, Marlene L; Carby, Martin

2014-10-01

The impact of Luminex-detected HLA antibodies on outcomes after lung transplantation is unclear. Herein we have undertaken a retrospective study of pre-transplant sera from 425 lung transplants performed between 1991 and 2003. Pre-transplant sera, originally screened by complement-dependent cytotoxicity (CDC) assays, were retrospectively tested for the presence of HLA-specific antibodies using HLA-coated Luminex beads and C4d deposition on Luminex beads. The results were correlated with graft survival at 1 year. Twenty-seven patients were retrospectively identified as having been transplanted against donor-specific HLA antibodies (DSA) and 36 patients against non-donor-specific HLA antibodies (NDSA). DSA-positive patients had 1-year survival of 51.9% compared with 77.8% for NDSA and 71.8% for antibody-negative patients (p = 0.029). One-year survival of patients with complement-fixing DSA was 12.5% compared with 62.5% for non-complement-fixing DSA, 75.8% for non-complement-fixing NDSA and 71.8% for antibody-negative patients (p < 0.0001). DSA-positive patients with mean fluorescence intensity (MFI) >5,000 had 1-year survival of 33.3% compared with 71.4% for MFI 2,000 to 5000 and 62.5% for MFI <2,000 (p = 0.0046). Multivariable analysis revealed DSA to be an independent predictor of poor patient survival within 1 year (p = 0.0010, hazard ratio [HR] = 3.569) as well as complement-fixing DSA (p < 0.0001, HR = 11.083) and DSA with MFI >5,000 (p = 0.0001, HR = 5.512). Pre-formed DSA, particularly complement-fixing DSA, and high MFI are associated with poor survival within the first year after lung transplantation. Risk stratification according to complement fixation or MFI levels may allow for increased transplantation in sensitized patients. Copyright © 2014 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

Scabies Mite Peritrophins Are Potential Targets of Human Host Innate Immunity

PubMed Central

Holt, Deborah C.; Kemp, Dave J.; Fischer, Katja

2011-01-01

Background Pruritic scabies lesions caused by Sarcoptes scabiei burrowing in the stratum corneum of human skin facilitate opportunistic bacterial infections. Emerging resistance to current therapeutics emphasizes the need to identify novel targets for protective intervention. We have characterized several protein families located in the mite gut as crucial factors for host-parasite interactions. Among these multiple proteins inhibit human complement, presumably to avoid complement-mediated damage of gut epithelial cells. Peritrophins are major components of the peritrophic matrix often found in the gut of arthropods. We hypothesized that a peritrophin, if abundant in the scabies mite gut, could be an activator of complement. Methodology/Principal Findings A novel full length scabies mite peritrophin (SsPTP1) was identified in a cDNA library from scabies mites. The amino acid sequence revealed four putative chitin binding domains (CBD). Recombinant expression of one CBD of the highly repetitive SsPTP1 sequence as TSP-hexaHis-fusion protein resulted in soluble protein, which demonstrated chitin binding activity in affinity chromatography assays. Antibodies against a recombinant SsPTP1 fragment were used to immunohistochemically localize native SsPTP1 in the mite gut and in fecal pellets within the upper epidermis, co-localizing with serum components such as host IgG and complement. Enzymatic deglycosylation confirmed strong N- and O-glycosylation of the native peritrophin. Serum incubation followed by immunoblotting with a monoclonal antibody against mannan binding lectin (MBL), the recognition molecule of the lectin pathway of human complement activation, indicated that MBL may specifically bind to glycosylated SsPTP1. Conclusions/Significance This study adds a new aspect to the accumulating evidence that complement plays a major role in scabies mite biology. It identifies a novel peritrophin localized in the mite gut as a potential target of the lectin pathway of the complement cascade. These initial findings indicate a novel role of scabies mite peritrophins in triggering a host innate immune response within the mite gut. PMID:21980545

University of Rhode Island Adapted Aquatics Program Manual. Second Edition.

ERIC Educational Resources Information Center

Bloomquist, Lorraine E.

This manual provides guidelines for aquatic teachers of people with disabilities. It is based on experience in teaching American Red Cross Adapted Aquatics and is to be used to complement and accompany the Red Cross Adapted Aquatics materials. Emphasis is placed on successful experiences in a positive, safe, reinforcing environment stressing…

Clinical Environment as a Learning Environment: Student Nurses' Perceptions Concerning Clinical Learning Experiences.

ERIC Educational Resources Information Center

Papp, Inkeri; Markkanen, Marjatta; von Bonsdorff, Mikaela

2003-01-01

Finnish student nurses (n=16) described their clinical learning experiences. Several themes were identified: feeling appreciated and supported, the quality of mentoring and patient care, and self-directedness. School and clinical staff cooperation helped create a good learning environment in which theory and practice complemented each other.…

An Environmental Chemistry Experiment: The Determination of Radon Levels in Water.

ERIC Educational Resources Information Center

Welch, Lawrence E.; Mossman, Daniel M.

1994-01-01

Describes a radiation experiment developed to complement a new environmental chemistry laboratory curriculum. A scintillation counter is used to measure radon in water. The procedure relies on the fact that toluene will preferentially extract radon from water. Sample preparation is complete in less than 90 minutes. Because the level of…

Back to Basic: Aesthetic Experiences with Literature and Discovering the World

ERIC Educational Resources Information Center

Tice, Kathleen C.

2008-01-01

In this article, the author shares a current analysis of data that complements findings from earlier, related research that confirms the emotional aspects of reading experiences. The data from the earlier study is based upon comments by graduate students in online discussion groups, where they share their thoughts about the professional readings…

Travelling Academics: The Lived Experience of Academics Moving across Countries

ERIC Educational Resources Information Center

Uusimaki, Liisa; Garvis, Susanne

2017-01-01

The article reports on a study that explored the personal narratives of two female travelling academics at a Swedish University who had moved from Australia. To complement previous accounts of difficult migration and enculturation within the research literature, this article focuses mainly on the successful experiences of the academics and how…

Changes in membrane lipid composition in ethanol- and acid-adapted Oenococcus oeni cells: characterization of the cfa gene by heterologous complementation.

PubMed

Grandvalet, Cosette; Assad-García, Juan Simón; Chu-Ky, Son; Tollot, Marie; Guzzo, Jean; Gresti, Joseph; Tourdot-Maréchal, Raphaëlle

2008-09-01

Cyclopropane fatty acid (CFA) synthesis was investigated in Oenococcus oeni. The data obtained demonstrated that acid-grown cells or cells harvested in the stationary growth phase showed changes in fatty acid composition similar to those of ethanol-grown cells. An increase of the CFA content and a decrease of the oleic acid content were observed. The biosynthesis of CFAs from unsaturated fatty acid phospholipids is catalysed by CFA synthases. Quantitative real-time-PCR experiments were performed on the cfa gene of O. oeni, which encodes a putative CFA synthase. The level of cfa transcripts increased when cells were harvested in stationary phase and when cells were grown in the presence of ethanol or at low pH, suggesting transcriptional regulation of the cfa gene under different stress conditions. In contrast to Escherichia coli, only one functional promoter was identified upstream of the cfa gene of O. oeni. The function of the cfa gene was confirmed by complementation of a cfa-deficient E. coli strain. Nevertheless, the complementation remained partial because the conversion percentage of unsaturated fatty acids into CFA of the complemented strain was much lower than that of the wild-type strain. Moreover, a prevalence of cycC19 : 0 was observed in the membrane of the complemented strain. This could be due to a specific affinity of the CFA synthase from O. oeni. In spite of this partial complementation, the complemented strain of E. coli totally recovered its viability after ethanol shock (10 %, v/v) whereas its viability was only partly recovered after an acid shock at pH 3.0.

Boron nitride as two dimensional dielectric: Reliability and dielectric breakdown

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ji, Yanfeng; Pan, Chengbin; Hui, Fei

2016-01-04

Boron Nitride (BN) is a two dimensional insulator with excellent chemical, thermal, mechanical, and optical properties, which make it especially attractive for logic device applications. Nevertheless, its insulating properties and reliability as a dielectric material have never been analyzed in-depth. Here, we present the first thorough characterization of BN as dielectric film using nanoscale and device level experiments complementing with theoretical study. Our results reveal that BN is extremely stable against voltage stress, and it does not show the reliability problems related to conventional dielectrics like HfO{sub 2}, such as charge trapping and detrapping, stress induced leakage current, and untimelymore » dielectric breakdown. Moreover, we observe a unique layer-by-layer dielectric breakdown, both at the nanoscale and device level. These findings may be of interest for many materials scientists and could open a new pathway towards two dimensional logic device applications.« less

Discovery of a Small Molecule Probe That Post-Translationally Stabilizes the Survival Motor Neuron Protein for the Treatment of Spinal Muscular Atrophy.

PubMed

Rietz, Anne; Li, Hongxia; Quist, Kevin M; Cherry, Jonathan J; Lorson, Christian L; Burnett, Barrington G; Kern, Nicholas L; Calder, Alyssa N; Fritsche, Melanie; Lusic, Hrvoje; Boaler, Patrick J; Choi, Sungwoon; Xing, Xuechao; Glicksman, Marcie A; Cuny, Gregory D; Androphy, Elliot J; Hodgetts, Kevin J

2017-06-08

Spinal muscular atrophy (SMA) is the leading genetic cause of infant death. We previously developed a high-throughput assay that employs an SMN2-luciferase reporter allowing identification of compounds that act transcriptionally, enhance exon recognition, or stabilize the SMN protein. We describe optimization and characterization of an analog suitable for in vivo testing. Initially, we identified analog 4m that had good in vitro properties but low plasma and brain exposure in a mouse PK experiment due to short plasma stability; this was overcome by reversing the amide bond and changing the heterocycle. Thiazole 27 showed excellent in vitro properties and a promising mouse PK profile, making it suitable for in vivo testing. This series post-translationally stabilizes the SMN protein, unrelated to global proteasome or autophagy inhibition, revealing a novel therapeutic mechanism that should complement other modalities for treatment of SMA.

[Haemophilia A and B in dogs].

PubMed

Mischke, R

2012-01-01

Based on own clinical experiences and the literature, this review article elaborates on aspects of aetiology, pathogenesis, clinical signs, diagnosis and therapy of haemophilia A and B in dogs. When compared to humans, dogs reveal more severe haemorrhagic symptoms at a defined residual factor activity (e.g. subcutaneous, intramuscular, and intraarticular haemorrhages after inappropriate trauma resulting in lameness and paralysis, excessive haemorrhage during second dentition, venal puncture, and surgery). Fortunately, genetic tests are now commercially available in Germany for selected breeds (haemophilia B in Rhodesian Ridgebacks; haemophilia A in Havaneses), which complement the conventional individual factor activity measurements and facilitate the detection of female carrier dogs. Treatment of bleeding crises is still mainly based on substitution therapy with fresh or fresh frozen plasma in addition to local haemostatic measures. In contrast, expectations regarding the timely clinical availability of gene therapy (particularly in humans) have not yet been fulfilled.

Social Learning and Culture in Child and Chimpanzee.

PubMed

Whiten, Andrew

2017-01-03

A few decades ago, we knew next to nothing about the behavior of our closest animal relative, the chimpanzee, but long-term field studies have since revealed an undreamed-of richness in the diversity of their cultural traditions across Africa. These discoveries have been complemented by a substantial suite of experimental studies, now bridging to the wild through field experiments. These field and experimental studies, particularly those in which direct chimpanzee-child comparisons have been made, delineate a growing set of commonalities between the phenomena of social learning and culture in the lives of chimpanzees and humans. These commonalities in social learning inform our understanding of the evolutionary roots of the cultural propensities the species share. At the same time, such comparisons throw into clearer relief the unique features of the distinctive human capacity for cumulative cultural evolution, and new research has begun to probe the key psychological attributes that may explain it.

Attachment patterns of Arabs and Jews in Israel--are we really so different?

PubMed

Lavy, Shiri; Azaiza, Faisal; Mikulincer, Mario

2012-01-01

Attachment orientations reflect internal representations of self, others, and relationships. Studies revealed meaningful cultural differences in attachment orientations, but few included Arab samples. to fill this gap, we compared attachment orientations of Jews and Arabs in Israel using valid measures. Israeli participants (292 Arabs and 206 Jews) described their attachment figures and completed the Experiences in Close Relationships questionnaire which measures anxious and avoidant attachment orientations in Arabic and Hebrew, respectively. Israeli Arabs reported higher attachment anxiety than Israeli Jews, but no difference was found in avoidance. Both groups reported that attachment figures were similar in gender and relationship type, and included romantic partners, relatives and friends. Findings should be considered cautiously due to sampling limitations. the results complement previous cross-cultural findings and Arabs-Jews differences in relationship-related norms/values. Higher attachment-anxiety scores observed among Israeli Arabs may be considered culturally normative with implications for the development of culturally competent interventions.

Atomic force microscopy studies on cellular elastic and viscoelastic properties.

PubMed

Li, Mi; Liu, Lianqing; Xi, Ning; Wang, Yuechao

2018-01-01

In this work, a method based on atomic force microscopy (AFM) approach-reside-retract experiments was established to simultaneously quantify the elastic and viscoelastic properties of single cells. First, the elastic and viscoelastic properties of normal breast cells and cancerous breast cells were measured, showing significant differences in Young's modulus and relaxation times between normal and cancerous breast cells. Remarkable differences in cellular topography between normal and cancerous breast cells were also revealed by AFM imaging. Next, the elastic and viscoelasitc properties of three other types of cell lines and primary normal B lymphocytes were measured; results demonstrated the potential of cellular viscoelastic properties in complementing cellular Young's modulus for discerning different states of cells. This research provides a novel way to quantify the mechanical properties of cells by AFM, which allows investigation of the biomechanical behaviors of single cells from multiple aspects.

Complement factor h is critical in the maintenance of retinal perfusion.

PubMed

Lundh von Leithner, Peter; Kam, Jaimie Hoh; Bainbridge, James; Catchpole, Ian; Gough, Gerald; Coffey, Peter; Jeffery, Glen

2009-07-01

Vascular pathologies are known to be associated with age-related macular degeneration. Recently, age-related macular degeneration was associated with a single-nucleotide substitution of the complement factor H (CFH) gene, part of the alternative pathway of the complement system, a critical element in the innate immune response. Such polymorphisms are found in more than 50% of cases of age-related macular degeneration. Here we show that the absence of CFH causes an autoimmune response that targets the vascular endothelium of both the inner and outer retinal vascular networks. In CFH-knockout (cfh(-/-)) mice, C3 and C3b, key components of the complement system, are progressively deposited on retinal vessels, which subsequently become restricted and wither, resulting in a reduction of retinal blood supply. This result leads to increased oxygen stress. While such effects are not systemic, these structural changes are mirrored in functional changes with a substantial decline in retinal blood flow dynamics. When the system is challenged functionally by laser-induced choroidal neovascularization, fluorescein leakage was significantly smaller in cfh(-/-) mice compared with controls, likely due to reduced retinal perfusion. These data reveal that in both the presence and absence of exogenous challenge to the innate immune system, CFH is required to maintain normal levels of retinal perfusion. It is likely that C3 and C3b accumulation in the aged CFH-deficient retina is associated with complement-mediated retinal endothelium destruction.

Expression of endogenous and foreign ribulose 1,5-bisphosphate carboxylase-oxygenase (RubisCO) genes in a RubisCO deletion mutant of Rhodobacter sphaeroides.

PubMed Central

Falcone, D L; Tabita, F R

1991-01-01

A Rhodobacter sphaeroides ribulose 1,5-bisphosphate carboxylase-oxygenase (RubisCO) deletion strain was constructed that was complemented by plasmids containing either the form I or form II CO2 fixation gene cluster. This strain was also complemented by genes encoding foreign RubisCO enzymes expressed from a Rhodospirillum rubrum RubisCO promoter. In R. sphaeroides, the R. rubrum promoter was regulated, resulting in variable levels of disparate RubisCO molecules under different growth conditions. Photosynthetic growth of the R. sphaeroides deletion strain complemented with cyanobacterial RubisCO revealed physiological properties reflective of the unique cellular environment of the cyanobacterial enzyme. The R. sphaeroides RubisCO deletion strain and R. rubrum promoter system may be used to assess the properties of mutagenized proteins in vivo, as well as provide a potential means to select for altered RubisCO molecules after random mutagenesis of entire genes or gene regions encoding RubisCO enzymes. Images PMID:1900508

Effects of Pectic Polysaccharides Isolated from Leek on the Production of Reactive Oxygen and Nitrogen Species by Phagocytes

PubMed Central

Nikolova, Mariana; Ambrozova, Gabriela; Kratchanova, Maria; Denev, Petko; Kussovski, Veselin; Ciz, Milan

2013-01-01

Abstract The current survey investigates the effect of four polysaccharides isolated from fresh leek or alcohol insoluble substances (AIS) of leek on the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) from phagocytes. The ability of the polysaccharides to activate serum complement was also investigated. Despite the lack of antioxidant activity, the pectic polysaccharides significantly decreased the production of ROS by human neutrophils. Polysaccharides isolated from AIS markedly activated RAW 264.7 macrophages for RNS production in a concentration-dependent manner. The Western blot analysis revealed that this effect was due to the stimulation of the inducible nitric oxide synthase protein expression of macrophages. The polysaccharides extracted from AIS with water showed the ability to fix serum complement, especially through the alternative pathway. It was found that the polysaccharide that has the highest complement-fixing effect is characterized by the highest content of uronic acids and the highest molecular weight. PMID:23905651

Complement Inhibitors from Scabies Mites Promote Streptococcal Growth – A Novel Mechanism in Infected Epidermis?

PubMed Central

Mika, Angela; Reynolds, Simone L.; Pickering, Darren; McMillan, David; Sriprakash, Kadaba S.; Kemp, David J.; Fischer, Katja

2012-01-01

Background Scabies is highly prevalent in socially disadvantaged communities such as indigenous populations and in developing countries. Generalized itching causes discomfort to the patient; however, serious complications can occur as a result of secondary bacterial pyoderma, commonly caused by Streptococcus pyogenes (GAS) or Staphylococcus aureus. In the tropics, skin damage due to scabies mite infestations has been postulated to be an important link in the pathogenesis of disease associated with acute rheumatic fever and heart disease, poststreptococcal glomerulonephritis and systemic sepsis. Treatment of scabies decreases the prevalence of infections by bacteria. This study aims to identify the molecular mechanisms underlying the link between scabies and GAS infections. Methodology/Principal Findings GAS bacteria were pre-incubated with blood containing active complement, phagocytes and antibodies against the bacteria, and subsequently tested for viability by plate counts. Initial experiments were done with serum from an individual previously exposed to GAS with naturally acquired anti-GAS antibodies. The protocol was optimized for large-scale testing of low-opsonic whole blood from non-exposed human donors by supplementing with a standard dose of heat inactivated human sera previously exposed to GAS. This allowed an extension of the dataset to two additional donors and four proteins tested at a range of concentrations. Shown first is the effect of scabies mite complement inhibitors on human complement using ELISA-based complement activation assays. Six purified recombinant mite proteins tested at a concentration of 50 µg/ml blocked all three complement activation pathways. Further we demonstrate in human whole blood assays that each of four scabies mite complement inhibitors tested increased GAS survival rates by 2–15 fold. Conclusions/Significance We propose that local complement inhibition plays an important role in the development of pyoderma in scabies infested skin. This molecular link between scabies and bacterial infections may provide new avenues to develop alternative treatment options against this neglected disease. PMID:22815998

Simulation of FRET dyes allows quantitative comparison against experimental data

NASA Astrophysics Data System (ADS)

Reinartz, Ines; Sinner, Claude; Nettels, Daniel; Stucki-Buchli, Brigitte; Stockmar, Florian; Panek, Pawel T.; Jacob, Christoph R.; Nienhaus, Gerd Ulrich; Schuler, Benjamin; Schug, Alexander

2018-03-01

Fully understanding biomolecular function requires detailed insight into the systems' structural dynamics. Powerful experimental techniques such as single molecule Förster Resonance Energy Transfer (FRET) provide access to such dynamic information yet have to be carefully interpreted. Molecular simulations can complement these experiments but typically face limits in accessing slow time scales and large or unstructured systems. Here, we introduce a coarse-grained simulation technique that tackles these challenges. While requiring only few parameters, we maintain full protein flexibility and include all heavy atoms of proteins, linkers, and dyes. We are able to sufficiently reduce computational demands to simulate large or heterogeneous structural dynamics and ensembles on slow time scales found in, e.g., protein folding. The simulations allow for calculating FRET efficiencies which quantitatively agree with experimentally determined values. By providing atomically resolved trajectories, this work supports the planning and microscopic interpretation of experiments. Overall, these results highlight how simulations and experiments can complement each other leading to new insights into biomolecular dynamics and function.

On the temporality of creative insight: a psychological and phenomenological perspective

PubMed Central

Cosmelli, Diego; Preiss, David D.

2014-01-01

Research into creative insight has had a strong emphasis on the psychological processes underlying problem-solving situations as a standard model for the empirical study of this phenomenon. Although this model has produced significant advances in our scientific understanding of the nature of insight, we believe that a full comprehension of insight requires complementing cognitive and neuroscientific studies with a descriptive, first-person, phenomenological approach into how creative insight is experienced. Here we propose to take such first-person perspective while paying special attention to the temporal aspects of this experience. When this first-person perspective is taken into account, a dynamic past–future interplay can be identified at the core of the experience of creative insight, a structure that is compatible with both biological and biographical evidences. We believe this approach could complement and help bring together biological and psychological perspectives. Furthermore, we argue that because of its spontaneous but recurrent nature, creative insight could represent a relevant target for the phenomenological investigation of the flow of experience itself. PMID:25368595

Frictional processes during flank motion at Mount Etna (Italy): experimental characterisation of slip on similar and dissimilar volcanic and sedimentary rocks.

NASA Astrophysics Data System (ADS)

Rozanski, Wojciech; Lavallee, Yan; Kendrick, Jackie; Castagna, Angela; Mitchell, Thomas; Heap, Michael; Vinciguerra, Sergio; Hirose, Takehiro; Dingwell, Donald

2015-04-01

The edifice of Mount Etna (Italy) is structurally unstable, exhibiting a near continuous ESE seaward sliding along a set of faults due to interplay between regional tectonics, gravity instability and magma intrusion. Continuous seismic and ground deformation monitoring reveals the resulting large-scale flank motion at variable rates. The mechanisms controlling this faulting kinetic remains, however, poorly constrained. Examination of the fault zones reveals a range of rock types along the different fault segments: fresh and altered basalt, clay and limestone. As lithological contrasts can jeopardise the structural stability of an edifice, we experimentally investigate the frictional properties of these rocks using low- to high-velocity-rotary shear tests on similar and dissimilar rocks to better understand episodes of slow flank motion as well as rapid and catastrophic sector collapse events. The first set of experiments was performed at velocities up to 1.2 m/s and at normal stresses of 1.5 MPa, commensurate with depths of the contacts seen in the Etna edifice. Friction experiments on clay gouge shows the strong rate-weakening dependence of slip in this material as well as the release of carbon dioxide. Friction experiments on solid rocks show a wider range of mechanical behaviour. At high velocity (>0.6 m/s) volcanic rocks tend to melt whereas the clay and limestone do not; rather they decarbonate, which prevents the rock from achieving the temperature required for melting. Experiments on dissimilar rocks clearly show that composition of host rocks affects the composition and viscosity of the resultant frictional melt, which can have a dramatic effect on shear stress leading to fault weakening or strengthening depending on the combination of host rock samples. A series of low- to moderate-slip velocity experiments is now being conducted to complement our dataset and provide a more complete rock friction model applicable to Mount Etna.

Heterologous Expression of Der Homologs in an Escherichia coli der Mutant and Their Functional Complementation

PubMed Central

Choi, Eunsil; Kang, Nalae; Jeon, Young; Pai, Hyun-Sook

2016-01-01

ABSTRACT The unique Escherichia coli GTPase Der (double Era-like GTPase), which contains tandemly repeated GTP-binding domains, has been shown to play an essential role in 50S ribosomal subunit biogenesis. The depletion of Der results in the accumulation of precursors of 50S ribosomal subunits that are structurally unstable at low Mg2+ concentrations. Der homologs are ubiquitously found in eubacteria. Conversely, very few are conserved in eukaryotes, and none is conserved in archaea. In the present study, to verify their conserved role in bacterial 50S ribosomal subunit biogenesis, we cloned Der homologs from two gammaproteobacteria, Klebsiella pneumoniae and Salmonella enterica serovar Typhimurium; two pathogenic bacteria, Staphylococcus aureus and Neisseria gonorrhoeae; and the extremophile Deinococcus radiodurans and then evaluated whether they could functionally complement the E. coli der-null phenotype. Only K. pneumoniae and S. Typhimurium Der proteins enabled the E. coli der-null strain to grow under nonpermissive conditions. Sucrose density gradient experiments revealed that the expression of K. pneumoniae and S. Typhimurium Der proteins rescued the structural instability of 50S ribosomal subunits, which was caused by E. coli Der depletion. To determine what allows their complementation, we constructed Der chimeras. We found that only Der chimeras harboring both the linker and long C-terminal regions could reverse the growth defects of the der-null strain. Our findings suggest that ubiquitously conserved essential GTPase Der is involved in 50S ribosomal subunit biosynthesis in various bacteria and that the linker and C-terminal regions may participate in species-specific recognition or interaction with the 50S ribosomal subunit. IMPORTANCE In Escherichia coli, Der (double Era-like GTPase) is an essential GTPase that is important for the production of mature 50S ribosomal subunits. However, to date, its precise role in ribosome biogenesis has not been clarified. In this study, we used five Der homologs from gammaproteobacteria, pathogenic bacteria, and an extremophile to elucidate their conserved function in 50S ribosomal subunit biogenesis. Among them, Klebsiella pneumoniae and Salmonella enterica serovar Typhimurium Der homologs implicated the participation of Der in ribosome assembly in E. coli. Our results show that the linker and C-terminal regions of Der homologs are correlated with its functional complementation in E. coli der mutants, suggesting that they are involved in species-specific recognition or interaction with 50S ribosomal subunits. PMID:27297882

The SloR Metalloregulator is Involved in the Streptococcus mutans Oxidative Stress Response

PubMed Central

Crepps, Sarah C.; Fields, Emily E.; Galan, Diego; Corbett, John P.; Von Hasseln, Elizabeth R.; Spatafora, Grace A.

2015-01-01

SUMMARY A 25kDa SloR metalloregulatory protein in Streptococcus mutans modulates the expression of multiple genes, including the sloABC operon that encodes essential Mn2+ transport and genes that promote cariogenesis. In this study, we report on SloC- and SloR-deficient strains of S. mutans (GMS284 and GMS584, respectively) that demonstrate compromised survivorship compared to their UA159 wildtype progenitor and their complemented strains (GMS285 and GMS585, respectively), when challenged with streptonigrin and/or in growth competition experiments. The results of streptonigrin assays revealed significantly larger zones of inhibition for GMS584 than for either UA159 or GMS585, indicating weakened S. mutans survivorship in the absence of SloR. Competition assays revealed a compromised ability for GMS284 and GMS584 to survive peroxide challenge compared with their SloC- and SloR-proficient counterparts. These findings are consistent with a role for SloC and SloR in S. mutans aerotolerance. We also predicted differential expression of oxidative stress tolerance genes in GMS584 versus UA159 and GMS585 when grown aerobically. The results of qRT-PCR experiments revealed S. mutans sod, tpx, and sloC expression that was up-regulated in GMS584 compared to UA159 and GMS585, indicating that the impact of oxidative stress on S. mutans is more severe in the absence of SloR than in its presence. The results of electrophoretic mobility shift assays indicate that SloR does not bind to the sod or tpx promoter regions directly, implicating intermediaries that may arbitrate the SloR response to oxidative stress. PMID:26577188

The SloR metalloregulator is involved in the Streptococcus mutans oxidative stress response.

PubMed

Crepps, S C; Fields, E E; Galan, D; Corbett, J P; Von Hasseln, E R; Spatafora, G A

2016-12-01

SloR, a 25-kDa metalloregulatory protein in Streptococcus mutans modulates the expression of multiple genes, including the sloABC operon that encodes essential Mn 2+ transport and genes that promote cariogenesis. In this study, we report on SloC- and SloR-deficient strains of S. mutans (GMS284 and GMS584, respectively) that demonstrate compromised survivorship compared with their UA159 wild-type progenitor and their complemented strains (GMS285 and GMS585, respectively), when challenged with streptonigrin and/or in growth competition experiments. The results of streptonigrin assays revealed significantly larger zones of inhibition for GMS584 than for either UA159 or GMS585, indicating weakened S. mutans survivorship in the absence of SloR. Competition assays revealed a compromised ability for GMS284 and GMS584 to survive peroxide challenge compared with their SloC- and SloR-proficient counterparts. These findings are consistent with a role for SloC and SloR in S. mutans aerotolerance. We also predicted differential expression of oxidative stress tolerance genes in GMS584 versus UA159 and GMS585 when grown aerobically. The results of quantitative RT-PCR experiments revealed S. mutans sod, tpx, and sloC expression that was upregulated in GMS584 compared with UA159 and GMS585, indicating that the impact of oxidative stress on S. mutans is more severe in the absence of SloR than in its presence. The results of electrophoretic mobility shift assays indicate that SloR does not bind to the sod or tpx promoter regions directly, implicating intermediaries that may arbitrate the SloR response to oxidative stress. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Enhanced change detection performance reveals improved strategy use in avid action video game players.

PubMed

Clark, Kait; Fleck, Mathias S; Mitroff, Stephen R

2011-01-01

Recent research has shown that avid action video game players (VGPs) outperform non-video game players (NVGPs) on a variety of attentional and perceptual tasks. However, it remains unknown exactly why and how such differences arise; while some prior research has demonstrated that VGPs' improvements stem from enhanced basic perceptual processes, other work indicates that they can stem from enhanced attentional control. The current experiment used a change-detection task to explore whether top-down strategies can contribute to VGPs' improved abilities. Participants viewed alternating presentations of an image and a modified version of the image and were tasked with detecting and localizing the changed element. Consistent with prior claims of enhanced perceptual abilities, VGPs were able to detect the changes while requiring less exposure to the change than NVGPs. Further analyses revealed this improved change detection performance may result from altered strategy use; VGPs employed broader search patterns when scanning scenes for potential changes. These results complement prior demonstrations of VGPs' enhanced bottom-up perceptual benefits by providing new evidence of VGPs' potentially enhanced top-down strategic benefits. Copyright © 2010 Elsevier B.V. All rights reserved.

Beyond Contagion: Reality Mining Reveals Complex Patterns of Social Influence.

PubMed

Alshamsi, Aamena; Pianesi, Fabio; Lepri, Bruno; Pentland, Alex; Rahwan, Iyad

2015-01-01

Contagion, a concept from epidemiology, has long been used to characterize social influence on people's behavior and affective (emotional) states. While it has revealed many useful insights, it is not clear whether the contagion metaphor is sufficient to fully characterize the complex dynamics of psychological states in a social context. Using wearable sensors that capture daily face-to-face interaction, combined with three daily experience sampling surveys, we collected the most comprehensive data set of personality and emotion dynamics of an entire community of work. From this high-resolution data about actual (rather than self-reported) face-to-face interaction, a complex picture emerges where contagion (that can be seen as adaptation of behavioral responses to the behavior of other people) cannot fully capture the dynamics of transitory states. We found that social influence has two opposing effects on states: adaptation effects that go beyond mere contagion, and complementarity effects whereby individuals' behaviors tend to complement the behaviors of others. Surprisingly, these effects can exhibit completely different directions depending on the stable personality or emotional dispositions (stable traits) of target individuals. Our findings provide a foundation for richer models of social dynamics, and have implications on organizational engineering and workplace well-being.

Strengthening the Role of Part-Time Faculty in Community Colleges. Focus Group Toolkit

ERIC Educational Resources Information Center

Center for Community College Student Engagement, 2014

2014-01-01

The Center for Community College Student Engagement encourages colleges to hold focus groups with part-time and full-time faculty to learn about differences in the faculty and their experience at their college and to complement survey data. Survey responses tell the "what" about faculty's experiences; through conducting focus groups,…

Long-range Transport of Aerosol at a Mountain Site in the Western Mediterranean Basin

NASA Astrophysics Data System (ADS)

Roberts, Greg; Corrigan, Craig; Ritchie, John; Pont, Véronique; Claeys, Marine; Sciare, Jean; Dulac, François

2016-04-01

The Mediterranean Region has been identified as sensitive to changes in the hydrological cycle, which could affect the water resources for millions of people by the turn of the century. However, prior to recent observations, most climate models have not accounted for the impacts of aerosol in this region. Past airborne studies have shown that aerosol sources from Europe and Africa are often transported throughout the lower troposphere; yet, because of their complex vertical distribution, it is a challenge to capture the variability and quantify the contribution of these sources to the radiative budget and precipitation processes. The PAEROS ChArMEx Mountain Experiment (PACMEx) complemented the regional activities by collecting aerosol data from atop a mountain on the island of Corsica, France in order to assess boundary layer / free troposphere atmospheric processes. In June/July 2013, PACMEx instruments were deployed at 2000 m.asl near the center of Corsica, France to complement ground-based aerosol observations at 550 m.asl on the northern peninsula, as well as airborne measurements. Comparisons between the peninsula site and the mountain site show similar general trends in aerosol properties; yet, differences in aerosol properties reveal the myriad transport mechanisms over the Mediterranean Basin. Using aerosol physicochemical data coupled with back trajectory analysis, different sources have been identified including Saharan dust transport, residual dust mixed with sea salt, anthropogenic emissions from Western Europe, and a period of biomass burning from Eastern Europe. Each period exhibits distinct signatures in the aerosol related to transport processes above and below the boundary layer. In addition, the total aerosol concentrations at the mountain site revealed a strong diurnal cycling the between the atmospheric boundary layer and the free troposphere, which is typical of mountain-top observations. PACMEx was funded by the National Science Foundation (NSF) as a cooperative collaboration with French research agencies (INSU-MISTRALS, ANR-ADRIMED, and Météo France).

Sources and Transport of Aerosol above the Boundary Layer over the Mediterranean Basin

NASA Astrophysics Data System (ADS)

Roberts, Greg; Corrigan, Craig; Ritchie, John; Pont, Veronique; Claeys, Marine; Sciare, Jean; Mallet, Marc; Dulac, François; Mihalopoulos, Nikos

2015-04-01

The Mediterranean Region has been identified as sensitive to changes in the hydrological cycle, which could affect the water resources for millions of people by the turn of the century. However, prior to recent observations, most climate models have not accounted for the impacts of aerosol in this region. Past airborne studies have shown that aerosol sources from Europe and Africa are often transported throughout the lower troposphere; yet, because of their complex vertical distribution, it is a challenge to capture the variability and quantify the contribution of these sources to the radiative budget and precipitation processes. The PAEROS ChArMEx Mountain Experiment (PACMEx) complemented the regional activities by collecting aerosol data from atop a mountain on the island of Corsica, France in order to assess boundary layer / free troposphere atmospheric processes. In June/July 2013, PACMEx instruments were deployed at 2000 m.asl near the center of Corsica, France to complement ground-based aerosol observations at 550 m.asl on the northern peninsula, as well as airborne measurements. Comparisons between the peninsula site and the mountain site show similar general trends in aerosol properties; yet, differences in aerosol properties reveal the myriad transport mechanisms over the Mediterranean Basin. Using aerosol physicochemical data coupled with back trajectory analysis, different sources have been identified including Saharan dust transport, residual dust mixed with sea salt, anthropogenic emissions from Western Europe, and a period of biomass burning from Eastern Europe. Each period exhibits distinct signatures in the aerosol related to transport processes above and below the boundary layer. In addition, the total aerosol concentrations at the mountain site revealed a strong diurnal cycling the between the atmospheric boundary layer and the free troposphere, which is typical of mountain-top observations. PACMEx was funded by the National Science Foundation (NSF) as a cooperative collaboration with French research agencies (INSU-MISTRALS, ANR-ADRIMED, and Météo France).

Therapeutic concentration of lithium stimulates complement C3 production in dendritic cells and microglia via GSK-3 inhibition.

PubMed

Yu, Zhiqian; Ono, Chiaki; Aiba, Setsuya; Kikuchi, Yoshie; Sora, Ichiro; Matsuoka, Hiroo; Tomita, Hiroaki

2015-02-01

Evidence indicates that widely prescribed mood stabilizer, lithium (Li), mediates cellular functions of differentiated monocytic cells, including microglial migration, monocyte-derived dendritic cell (MoDC) differentiation, and amelioration of monocytic malfunctions observed in neuropsychiatric diseases. Here, we surveyed molecules which take major roles in regulating these monocytic cellular functions. MoDCs treated with 1 and 5 mM Li, and microglia separated from Li-treated mice were subjected to microarray-based comprehensive gene expression analyses. Findings were validated using multiple experiments, including quantitative PCR, ELISA and immunostaining studies. Differing effects of Li on the two cell types were observed. Inflammation- and chemotaxis-relevant genes were significantly over-represented among Li-induced genes in MoDCs, whereas no specific category of genes was over-represented in microglia. The third component of complement (C3) was the only gene which was significantly induced by a therapeutic concentration of Li in both MoDCs and microglia. C3 production was increased by Li via GSK-3 inhibition. Li-induced C3 production was seen only in differentiated monocytic cells, but not in circulating monocytes. Our findings highlight a link between Li treatment and C3 production in differentiated monocytic cells, and reveal a regulatory role of GSK-3 in C3 production. Induction of microglial C3 production might be a novel neuroprotective mechanism of Li via regulating interactions between microglia and neurons. GLIA 2015;63:257-270. © 2014 Wiley Periodicals, Inc.

Accumulation of intra-cellular polyphosphate in Chlorella vulgaris cells is related to indole-3-acetic acid produced by Azospirillum brasilense.

PubMed

Meza, Beatriz; de-Bashan, Luz E; Hernandez, Juan-Pablo; Bashan, Yoav

2015-06-01

Accumulation of intra-cellular phosphate, as polyphosphate, was measured when the microalga Chlorella vulgaris was immobilized in alginate with either of two wild-type strains of the microalgae growth-promoting bacterium Azospirillum brasilense or their corresponding IAA-attenuated mutants. Wild type strains of A. brasilense induced higher amounts of intra-cellular phosphate in Chlorella than their respective mutants. Calculations comparing intra-cellular phosphate accumulation by culture or net accumulation by the cell and the amount of IAA that was produced by each of these strains revealed that higher IAA was linked to higher accumulations of intra-cellular phosphate. Application of four levels of exogenous IAA reported for A. brasilense and their IAA-attenuated mutants to cultures of C. vulgaris enhanced accumulation of intra-cellular phosphate; the higher the content of IAA per culture or per single cell, the higher was the amount of accumulated phosphate. When an IAA-attenuated mutant was complemented with exogenous IAA, accumulation of intra-cellular phosphate at the culture level was even higher than phosphate accumulation with the respective wild type strains. When calculating the net accumulation of intra-cellular phosphate in the complementation experiment, net intra-cellular phosphate induced by the IAA-attenuated mutant was completely restored and was similar to the wild strains. We propose that IAA produced by A. brasilense is linked to polyphosphate accumulation in C. vulgaris. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Identical substitutions in magnesium chelatase paralogs result in chlorophyll deficient soybean mutants

USDA-ARS?s Scientific Manuscript database

The soybean (Glycine max (L.) Merr.) chlorophyll deficient line MinnGold is a spontaneous mutant characterized by yellow foliage. Map-based cloning and transgenic complementation revealed that the mutant phenotype is caused by a non-synonymous nucleotide substitution in the third exon of a Mg-chelat...

Social Support and the Receipt of Home Care Services.

ERIC Educational Resources Information Center

Chappell, Neena L.

1985-01-01

Compares differences between elderly who use formal home care services and those who do not. Data revealed users as less healthy and less active and as receiving more assistance from both formal and informal sources. Suggests that formal and informal services complement rather than substitute for one another. (NRB)

Deletion of the membrane complement inhibitor CD59a drives age and gender-dependent alterations to bone phenotype in mice.

PubMed

Bloom, Anja C; Collins, Fraser L; Van't Hof, Rob J; Ryan, Elizabeth S; Jones, Emma; Hughes, Timothy R; Morgan, B Paul; Erlandsson, Malin; Bokarewa, Maria; Aeschlimann, Daniel; Evans, Bronwen A J; Williams, Anwen S

2016-03-01

Degenerative joint diseases such as osteoarthritis are characterised by aberrant region-specific bone formation and abnormal bone mineral content. A recent study suggested a role for the complement membrane attack complex in experimental models of osteoarthritis. Since CD59a is the principal regulator of the membrane attack complex in mice, we evaluated the impact of CD59a gene deletion upon maintenance of bone architecture. In vivo bone morphology analysis revealed that male CD59a-deficient mice have increased femur length and cortical bone volume, albeit with reduced bone mineral density. However, this phenomenon was not observed in female mice. Histomorphometric analysis of the trabecular bone showed increased rates of bone homeostasis, with both increased bone resorption and mineral apposition rate in CD59a-deficient male mice. When bone cells were studied in isolation, in vitro osteoclastogenesis was significantly increased in male CD59a-deficient mice, although osteoblast formation was not altered. Our data reveal, for the first time, that CD59a is a regulator of bone growth and homeostasis. CD59a ablation in male mice results in longer and wider bones, but with less density, which is likely a major contributing factor for their susceptibility to osteoarthritis. These findings increase our understanding of the role of complement regulation in degenerative arthritis. Copyright © 2016 Amgen Inc. Published by Elsevier Inc. All rights reserved.

Relationship between complement activation, cellular uptake and surface physicochemical aspects of novel PEG-modified nanocapsules.

PubMed

Mosqueira, V C; Legrand, P; Gulik, A; Bourdon, O; Gref, R; Labarre, D; Barratt, G

2001-11-01

The aim of our work was to examine the relationship between modifications of the surface of nanocapsules (NC) by adsorption or covalent grafting of poly(ethylene oxide) (PEG), and changes in their phospholipid (PL) content on complement activation (C3 cleavage) and on uptake by macrophages. The physicochemical characterization of the NC included an investigation of their properties, such as surface charge, size, hydrophilicity, morphology and homogeneity. This is the first time that such properties have been correlated with biological interactions for NC, a novel carrier system with a structure more complex than nanospheres. C3 crossed immunoelectrophoresis revealed the reduced activation for NC with longer PEG chain and higher density, although all formulations induced C3 cleavage to a lesser or greater extent. NC bearing PEG covalently bound to the surface were weaker activators of complement than plain PLA [poly(D,L-lactide)] NC or nanospheres (NS). Furthermore, the fluorescent/confocal microscopy of J774A1 cells in contact with NC reveal a dramatically reduced interaction with PEG-bearing NC. However, the way in which PEG was attached (covalent or adsorbed) seemed to affect the mechanism of uptake. Taken together, these results suggest that the low level of protein binding to NC covered with a high density of 20kDa PEG chains is likely to be due to the steric barriers surrounding these particles, which prevents protein adsorption and reduces their interaction with macrophages.

Aftereffects of Lithium-Conditioned Stimuli on Consummatory Behavior

ERIC Educational Resources Information Center

Domjan, Michael; Gillan, Douglas J.

1977-01-01

To complement investigations of the direct effects of lithium toxicosis on consummatory behavior, these experiments were designed to determine the aftereffects on drinking of exposure to a conditioned stimulus previously paired with lithium. (Author/RK)

Singing emotionally: a study of pre-production, production, and post-production facial expressions

PubMed Central

Quinto, Lena R.; Thompson, William F.; Kroos, Christian; Palmer, Caroline

2014-01-01

Singing involves vocal production accompanied by a dynamic and meaningful use of facial expressions, which may serve as ancillary gestures that complement, disambiguate, or reinforce the acoustic signal. In this investigation, we examined the use of facial movements to communicate emotion, focusing on movements arising in three epochs: before vocalization (pre-production), during vocalization (production), and immediately after vocalization (post-production). The stimuli were recordings of seven vocalists' facial movements as they sang short (14 syllable) melodic phrases with the intention of communicating happiness, sadness, irritation, or no emotion. Facial movements were presented as point-light displays to 16 observers who judged the emotion conveyed. Experiment 1 revealed that the accuracy of emotional judgment varied with singer, emotion, and epoch. Accuracy was highest in the production epoch, however, happiness was well communicated in the pre-production epoch. In Experiment 2, observers judged point-light displays of exaggerated movements. The ratings suggested that the extent of facial and head movements was largely perceived as a gauge of emotional arousal. In Experiment 3, observers rated point-light displays of scrambled movements. Configural information was removed in these stimuli but velocity and acceleration were retained. Exaggerated scrambled movements were likely to be associated with happiness or irritation whereas unexaggerated scrambled movements were more likely to be identified as “neutral.” An analysis of singers' facial movements revealed systematic changes as a function of the emotional intentions of singers. The findings confirm the central role of facial expressions in vocal emotional communication, and highlight individual differences between singers in the amount and intelligibility of facial movements made before, during, and after vocalization. PMID:24808868

The two-component system VicRK regulates functions associated with Streptococcus mutans resistance to complement immunity.

PubMed

Alves, Livia A; Harth-Chu, Erika N; Palma, Thais H; Stipp, Rafael N; Mariano, Flávia S; Höfling, José F; Abranches, Jacqueline; Mattos-Graner, Renata O

2017-10-01

Streptococcus mutans, a dental caries pathogen, can promote systemic infections upon reaching the bloodstream. The two-component system (TCS) VicRK Sm of S. mutans regulates the synthesis of and interaction with sucrose-derived exopolysaccharides (EPS), processes associated with oral and systemic virulence. In this study, we investigated the mechanisms by which VicRK Sm affects S. mutans susceptibility to blood-mediated immunity. Compared with parent strain UA159, the vicK Sm isogenic mutant (UAvic) showed reduced susceptibility to deposition of C3b of complement, low binding to serum immunoglobulin G (IgG), and low frequency of C3b/IgG-mediated opsonophagocytosis by polymorphonuclear cells in a sucrose-independent way (P<.05). Reverse transcriptase quantitative polymerase chain reaction analysis comparing gene expression in UA159 and UAvic revealed that genes encoding putative peptidases of the complement (pepO and smu.399) were upregulated in UAvic in the presence of serum, although genes encoding murein hydrolases (SmaA and Smu.2146c) or metabolic/surface proteins involved in bacterial interactions with host components (enolase, GAPDH) were mostly affected in a serum-independent way. Among vicK Sm -downstream genes (smaA, smu.2146c, lysM, atlA, pepO, smu.399), only pepO and smu.399 were associated with UAvic phenotypes; deletion of both genes in UA159 significantly enhanced levels of C3b deposition and opsonophagocytosis (P<.05). Moreover, consistent with the fibronectin-binding function of PepO orthologues, UAvic showed increased binding to fibronectin. Reduced susceptibility to opsonophagocytosis was insufficient to enhance ex vivo persistence of UAvic in blood, which was associated with growth defects of this mutant under limited nutrient conditions. Our findings revealed that S. mutans employs mechanisms of complement evasion through peptidases, which are controlled by VicRK Sm. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Computational Labs Using VPython Complement Conventional Labs in Online and Regular Physics Classes

NASA Astrophysics Data System (ADS)

Bachlechner, Martina E.

2009-03-01

Fairmont State University has developed online physics classes for the high-school teaching certificate based on the text book Matter and Interaction by Chabay and Sherwood. This lead to using computational VPython labs also in the traditional class room setting to complement conventional labs. The computational modeling process has proven to provide an excellent basis for the subsequent conventional lab and allows for a concrete experience of the difference between behavior according to a model and realistic behavior. Observations in the regular class room setting feed back into the development of the online classes.

The potential for using canopy spectral reflectance as an indirect selection tool for yield improvement in winter wheat

NASA Astrophysics Data System (ADS)

Prasad, Bishwajit

Scope and methods of study. Complementing breeding effort by deploying alternative methods of identifying higher yielding genotypes in a wheat breeding program is important for obtaining greater genetic gains. Spectral reflectance indices (SRI) are one of the many indirect selection tools that have been reported to be associated with different physiological process of wheat. A total of five experiments (a set of 25 released cultivars from winter wheat breeding programs of the U.S. Great Plains and four populations of randomly derived recombinant inbred lines having 25 entries in each population) were conducted in two years under Great Plains winter wheat rainfed environments at Oklahoma State University research farms. Grain yield was measured in each experiment and biomass was measured in three experiments at three growth stages (booting, heading, and grainfilling). Canopy spectral reflectance was measured at three growth stages and eleven SRI were calculated. Correlation (phenotypic and genetic) between grain yield and SRI, biomass and SRI, heritability (broad sense) of the SRI and yield, response to selection and correlated response, relative selection efficiency of the SRI, and efficiency in selecting the higher yielding genotypes by the SRI were assessed. Findings and conclusions. The genetic correlation coefficients revealed that the water based near infrared indices (WI and NWI) were strongly associated with grain yield and biomass production. The regression analysis detected a linear relationship between the water based indices with grain yield and biomass. The two newly developed indices (NWI-3 and NWI-4) gave higher broad sense heritability than grain yield, higher direct response to selection compared to grain yield, correlated response equal to or higher than direct response for grain yield, relative selection efficiency greater than one, and higher efficiency in selecting higher yielding genotypes. Based on the overall genetic analysis required to establish any trait as an efficient indirect selection tool, the water based SRI (especially NWI-3 and NWI-4) have the potential to complement the classical breeding effort for selecting genotypes with higher yield potential in a winter wheat breeding program.

Complement activation and liver impairment in trichloroethylene-sensitized BALB/c mice.

PubMed

Zhang, Jiaxiang; Zha, Wansheng; Wang, Feng; Jiang, Tao; Xu, Shuhai; Yu, Junfeng; Zhou, Chengfan; Shen, Tong; Wu, Changhao; Zhu, Qixing

2013-01-01

Our recent studies have shown that trichloroethylene (TCE) was able to induce multisystem injuries in the form of occupational medicamentosa-like dermatitis, including skin, kidney, and liver damages. However, the role of complement activation in the immune-mediated liver injury is not known. This study examined the role of complement activation in the liver injury in a mouse model of TCE-induced sensitization. Treatment of female BALB/c mice with TCE under specific dosing protocols resulted in skin inflammation and sensitization. Skin edema and erythema occurred in TCE-sensitized groups. Trichloroethylene sensitization produced liver histopathological lesions, increased serum alanine aminotransferase, aspartate transaminase activities, and the relative liver weight. The concentrations of serum complement components C3a-desArg, C5a-desArg, and C5b-9 were significantly increased in 24-hour, 48-hour, and 72-hour sensitization-positive groups treated with TCE and peaked in the 72-hour sensitization-positive group. Depositions of C3a, C5a, and C5b-9 into the liver tissue were also revealed by immunohistochemistry. Immunofluorescence further verified high C5b-9 expression in 24-hour, 48-hour, and 72-hour sensitization-positive groups in response to TCE treatment. Reverse transcription-polymerase chain reaction detected C3 messenger RNA expression in the liver, and this was significantly increased in 24-hour and 48-hour sensitization-positive groups with a transient reduction at 72 hours. These results provide the first experimental evidence that complement activation may play a key role in the generation and progression of immune-mediated hepatic injury by exposure to TCE.

Development of the Design Laboratory.

ERIC Educational Resources Information Center

Silla, Harry

1986-01-01

Describes the design laboratory at the Stevens Institute of Technology (SIT). Considers course objectives, design projects, project structure, mechanical design, project management, and laboratory operation. This laboratory complements SIT's course in process design, giving students a complete design experience. (JN)

Achieving Very Low Levels of Detection: An Improved Surface-Enhanced Raman Scattering Experiment for the Physical Chemistry Teaching Laboratory

ERIC Educational Resources Information Center

McMillan, Brian G.

2016-01-01

This experiment was designed and successfully introduced to complement the nanochemistry taught to undergraduate students in a useful and interesting way. Colloidal Ag nanoparticles were synthesized by a simple, room-temperature method, and the resulting suspension was then used to study the surface-enhanced Raman scattering (SERS) of methylene…

Mission Information: Worksite Interview, Shadow Community Workers, Work Experience Program. CHOICE (Challenging Options in Career Education).

ERIC Educational Resources Information Center

Gans, Connie; And Others

The work-study guide is the third volume in the advanced level of a career education curriculum for elementary-secondary migrant children. Complementing the secondary level job information text and a workbook about decision making and self-awareness, the work-study guide is designed to accompany work exploration and experience programs. It…

Using NMR Spectroscopy to Probe the Chemo- and Diastereoselectivity in the NaBH[subscript 4] Reduction of Benzoin Acetate and Benzoin Benzoate

ERIC Educational Resources Information Center

Saba, Shahrokh; Cagino, Kristen; Bennett, Caitlin

2015-01-01

A pedagogically useful discovery-based undergraduate organic chemistry lab experiment probing the chemo- and diastereoselectivity in the NaBH[subscript 4] reduction of two chiral ketoesters (benzoin acetate and benzoin benzoate) has been developed. This experiment complements a previously described and highly popular discovery-based experiment…

Social complementation and growth advantages promote socially defective bacterial isolates.

PubMed

Kraemer, Susanne A; Velicer, Gregory J

2014-04-22

Social interactions among diverse individuals that encounter one another in nature have often been studied among animals but rarely among microbes. For example, the evolutionary forces that determine natural frequencies of bacteria that express cooperative behaviours at low levels remain poorly understood. Natural isolates of the soil bacterium Myxococcus xanthus sampled from the same fruiting body often vary in social phenotypes, such as group swarming and multicellular development. Here, we tested whether genotypes highly proficient at swarming or development might promote the persistence of less socially proficient genotypes from the same fruiting body. Fast-swarming strains complemented slower isolates, allowing the latter to keep pace with faster strains in mixed groups. During development, one low-sporulating strain was antagonized by high sporulators, whereas others with severe developmental defects had those defects partially complemented by high-sporulating strains. Despite declining in frequency overall during competition experiments spanning multiple cycles of development, developmentally defective strains exhibited advantages during the growth phases of competitions. These results suggest that microbes with low-sociality phenotypes often benefit from interacting with more socially proficient strains. Such complementation may combine with advantages at other traits to increase equilibrium frequencies of low-sociality genotypes in natural populations.

Structural and functional studies on Ribonuclease S, retro S and retro-inverso S peptides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pal-Bhowmick, Ipsita; Pati Pandey, Ramendra; Jarori, Gotam K.

2007-12-21

Ribonuclease S peptide and S protein offer a unique complementation system to understand the finer features of molecular recognition. In the present study the S peptide (1-16), and its retro and retro-inverso analogs have been analyzed for their structural and biological attributes. RPHPLC, CD, and NMR analyses have revealed that the physicochemical and conformational properties of the S peptide are distinct from those of its retro and retro-inverso analogs. On the functional side, while the S peptide complemented the S protein to give RNase activity, was recognized by anti-S peptide antibodies and induced T cell proliferation, neither the retro normore » the retro-inverso S peptides could do so.« less

Critical incidents reveal how patients with head and neck cancer construct their "secure base" as a "helping system".

PubMed

Isaksson, Joakim; Salander, Pär; Granström, Brith; Laurell, Göran

2014-01-01

Most studies of the psychosocial needs of patients with head and neck cancers (HNC) use predefined categories and explicitly ask for specified needs. These studies are important but should be complemented with inductive studies based on patients' own descriptions of experiences. This qualitative study is such a contribution. In repeated interviews positive and negative incidents were collected from 137 patients with HNC, and these experiences were categorized in dimensions expressing needs. A core category--"being included--neglected by a helping system"--emerged from the narrated incidents and was based on the dimensions engagement, competence, and information. The findings are easily related to attachment theory by stressing the significance of establishing trustful relationships with the health care staff, as attachment figures, who respond flexibly and sensitively to the patient's needs. In the constitution of health care as a helping system, all encounters between the patient and health care staff matters. Further research should preferably focus on the creation of guidelines for the constitution of health care as a helping system, that is, how the found factors of a helping system can be operationalized in clinical practice.

Telling the Investment Story: A Narrative Analysis of Shareholder Reports.

ERIC Educational Resources Information Center

Jameson, Daphne A.

2000-01-01

Analyzes shareholder reports of equity mutual funds whose total returns were high in absolute terms, but low in relative terms. Reveals that mixed-return shareholder reports use a nonlinear hyperstructure, dramatize ideas through contrasting narrators, embed a variety of subgenres, and complement verbal with visual discourse in order to make…

Learning by Undoing, "Democracy and Education," and John Dewey, the Colonial Traveler

ERIC Educational Resources Information Center

Papastephanou, Marianna

2017-01-01

The centennial anniversary of John Dewey's "Democracy and Education" has been celebrated this year in a reconstructive and utility-based spirit. The article considers this spirit and the need to complement it with a critical-deconstructive and "use-less" prism that will reveal shortcomings in Dewey's and our own political…

Two-dimensional NMR spectrometry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farrar, T.C.

1987-06-01

This article is the second in a two-part series. In part one (ANALYTICAL CHEMISTRY, May 15) the authors discussed one-dimensional nuclear magnetic resonance (NMR) spectra and some relatively advanced nuclear spin gymnastics experiments that provide a capability for selective sensitivity enhancements. In this article and overview and some applications of two-dimensional NMR experiments are presented. These powerful experiments are important complements to the one-dimensional experiments. As in the more sophisticated one-dimensional experiments, the two-dimensional experiments involve three distinct time periods: a preparation period, t/sub 0/; an evolution period, t/sub 1/; and a detection period, t/sub 2/.

Two mannose-binding lectin homologues and an MBL-associated serine protease are expressed in the gut epithelia of the urochordate species Ciona intestinalis.

PubMed

Skjoedt, Mikkel-Ole; Palarasah, Yaseelan; Rasmussen, Karina; Vitved, Lars; Salomonsen, Jan; Kliem, Anette; Hansen, Soren; Koch, Claus; Skjodt, Karsten

2010-01-01

The lectin complement pathway has important functions in vertebrate host defence and accumulating evidence of primordial complement components trace its emergence to invertebrate phyla. We introduce two putative mannose-binding lectin homologues (CioMBLs) from the urochordate species Ciona intestinalis. The CioMBLs display similarities with vertebrate MBLs and comprise a collagen-like region, alpha-helical coiled-coils and a carbohydrate recognition domain (CRD) with conserved residues involved in calcium and carbohydrate binding. Structural analysis revealed an oligomerization through interchain disulphide bridges between N-terminal cysteine residues and cysteines located between the neck region and the CRD. RT-PCR showed a tissue specific expression of CioMBL in the gut and by immunohistochemistry analysis we also demonstrated that CioMBL co-localize with an MBL-associated serine protease in the epithelia cells lining the stomach and intestine. In conclusion we present two urochordate MBLs and identify an associated serine protease, which support the concept of an evolutionary ancient origin of the lectin complement pathway.

Direct immunofluorescence of normal skin in rheumatoid arthritis.

PubMed

Fitzgerald, O M; Barnes, L; Woods, R; McHugh, L; Barry, C; O'Loughlin, S

1985-11-01

The clinical significance of previously described immunoglobulin and complement deposition in the superficial dermal vessel walls of patients with rheumatoid arthritis is unknown. In the present study, skin biopsies were obtained from the normal forearm and buttock of 48 unselected patients with rheumatoid arthritis and were examined by direct immunofluorescence (IF) for the presence of immunoglobulin (IgG,A,M) and complement (C3) in the vessel walls. Deposits of C3, IgM or IgG were detected in 10 patients. Five patients had deposits at the forearm sample alone, four patients had deposits at both biopsy sites, while one patient was positive at the buttock alone. Clinical features were similar in patients with and without vessel IF. However, patients with IF were significantly more seropositive with lower levels of complement and raised levels of serum IgA and IgM. There was also an increased level of circulating IgG immune complexes in these patients. Further analysis following exclusion of seronegative patients revealed similar results. This study suggests that the presence of vessel IF identifies a subgroup of patients who have evidence of more severe immunological disturbance.

Complementing Neurophysiology Education for Developing Countries via Cost-Effective Virtual Labs: Case Studies and Classroom Scenarios.

PubMed

Diwakar, Shyam; Parasuram, Harilal; Medini, Chaitanya; Raman, Raghu; Nedungadi, Prema; Wiertelak, Eric; Srivastava, Sanjeeva; Achuthan, Krishnashree; Nair, Bipin

2014-01-01

Classroom-level neuroscience experiments vary from detailed protocols involving chemical, physiological and imaging techniques to computer-based modeling. The application of Information and Communication Technology (ICT) is revolutionizing the current laboratory scenario in terms of active learning especially for distance education cases. Virtual web-based labs are an asset to educational institutions confronting economic issues in maintaining equipment, facilities and other conditions needed for good laboratory practice. To enhance education, we developed virtual laboratories in neuroscience and explored their first-level use in (Indian) University education in the context of developing countries. Besides using interactive animations and remotely-triggered experimental devices, a detailed mathematical simulator was implemented on a web-based software platform. In this study, we focused on the perceptions of technology adoption for a virtual neurophysiology laboratory as a new pedagogy tool for complementing college laboratory experience. The study analyses the effect of virtual labs on users assessing the relationship between cognitive, social and teaching presence. Combining feedback from learners and teachers, the study suggests enhanced motivation for students and improved teaching experience for instructors.

Complementing Neurophysiology Education for Developing Countries via Cost-Effective Virtual Labs: Case Studies and Classroom Scenarios

PubMed Central

Diwakar, Shyam; Parasuram, Harilal; Medini, Chaitanya; Raman, Raghu; Nedungadi, Prema; Wiertelak, Eric; Srivastava, Sanjeeva; Achuthan, Krishnashree; Nair, Bipin

2014-01-01

Classroom-level neuroscience experiments vary from detailed protocols involving chemical, physiological and imaging techniques to computer-based modeling. The application of Information and Communication Technology (ICT) is revolutionizing the current laboratory scenario in terms of active learning especially for distance education cases. Virtual web-based labs are an asset to educational institutions confronting economic issues in maintaining equipment, facilities and other conditions needed for good laboratory practice. To enhance education, we developed virtual laboratories in neuroscience and explored their first-level use in (Indian) University education in the context of developing countries. Besides using interactive animations and remotely-triggered experimental devices, a detailed mathematical simulator was implemented on a web-based software platform. In this study, we focused on the perceptions of technology adoption for a virtual neurophysiology laboratory as a new pedagogy tool for complementing college laboratory experience. The study analyses the effect of virtual labs on users assessing the relationship between cognitive, social and teaching presence. Combining feedback from learners and teachers, the study suggests enhanced motivation for students and improved teaching experience for instructors. PMID:24693260

Characterization of shark complement factor I gene(s): genomic analysis of a novel shark-specific sequence.

PubMed

Shin, Dong-Ho; Webb, Barbara M; Nakao, Miki; Smith, Sylvia L

2009-07-01

Complement factor I is a crucial regulator of mammalian complement activity. Very little is known of complement regulators in non-mammalian species. We isolated and sequenced four highly similar complement factor I cDNAs from the liver of the nurse shark (Ginglymostoma cirratum), designated as GcIf-1, GcIf-2, GcIf-3 and GcIf-4 (previously referred to as nsFI-a, -b, -c and -d) which encode 689, 673, 673 and 657 amino acid residues, respectively. They share 95% (

Characterization of shark complement factor I gene(s): genomic analysis of a novel shark-specific sequence

PubMed Central

Shin, Dong-Ho; Webb, Barbara M.; Nakao, Miki; Smith, Sylvia L.

2009-01-01

Complement factor I is a crucial regulator of mammalian complement activity. Very little is known of complement regulators in non-mammalian species. We isolated and sequenced four highly similar complement factor I cDNAs from the liver of the nurse shark (Ginglymostoma cirratum), designated as GcIf-1, GcIf-2, GcIf-3 and GcIf-4 (previously referred to as nsFI-a, -b, -c and –d) which encode 689, 673, 673 and 657 amino acid residues, respectively. They share 95% (≤) amino acid identities with each other, 35.4 ~ 39.6% and 62.8 ~ 65.9% with factor I of mammals and banded houndshark (Triakis scyllium), respectively. The modular structure of the GcIf is similar to that of mammals with one notable exception, the presence of a novel shark-specific sequence between the leader peptide (LP) and the factor I membrane attack complex (FIMAC) domain. The cDNA sequences differ only in the size and composition of the shark-specific region (SSR). Sequence analysis of each SSR has identified within the region two novel short sequences (SS1 and SS2) and three repeat sequences (RS1, 2 and 3). Genomic analysis has revealed the existence of three introns between the leader peptide and the FIMAC domain, tentatively designated intron 1, intron 2, and intron 3 which span 4067, 2293 and 2082 bp, respectively. Southern blot analysis suggests the presence of a single gene copy for each cDNA type. Phylogenetic analysis suggests that complement factor I of cartilaginous fish diverged prior to the emergence of mammals. All four GcIf cDNA species are expressed in four different tissues and the liver is the main tissue in which expression level of all four is high. This suggests that the expression of GcIf isotypes is tissue-dependent. PMID:19423168

The Lectin Complement Pathway Is Involved in Protection Against Enteroaggregative Escherichia coli Infection.

PubMed

Adler Sørensen, Camilla; Rosbjerg, Anne; Hebbelstrup Jensen, Betina; Krogfelt, Karen Angeliki; Garred, Peter

2018-01-01

Enteroaggregative Escherichia coli (EAEC) causes acute and persistent diarrhea worldwide. Still, the involvement of host factors in EAEC infections is unresolved. Binding of recognition molecules from the lectin pathway of complement to EAEC strains have been observed, but the importance is not known. Our aim was to uncover the involvement of these molecules in innate complement dependent immune protection toward EAEC. Binding of mannose-binding lectin, ficolin-1, -2, and -3 to four prototypic EAEC strains, and ficolin-2 binding to 56 clinical EAEC isolates were screened by a consumption-based ELISA method. Flow cytometry was used to determine deposition of C4b, C3b, and the bactericidal C5b-9 membrane attack complex (MAC) on the bacteria in combination with different complement inhibitors. In addition, the direct serum bactericidal effect was assessed. Screening of the prototypic EAEC strains revealed that ficolin-2 was the major binder among the lectin pathway recognition molecules. However, among the clinical EAEC isolates only a restricted number ( n  = 5) of the isolates bound ficolin-2. Using the ficolin-2 binding isolate C322-17 as a model, we found that incubation with normal human serum led to deposition of C4b, C3b, and to MAC formation. No inhibition of complement deposition was observed when a C1q inhibitor was added, while partial inhibition was observed when ficolin-2 or factor D inhibitors were used separately. Combining the inhibitors against ficolin-2 and factor D led to virtually complete inhibition of complement deposition and protection against direct bacterial killing. These results demonstrate that ficolin-2 may play an important role in innate immune protection against EAEC when an appropriate ligand is exposed, but many EAEC strains evade lectin pathway recognition and may, therefore, circumvent this strategy of innate host immune protection.

Complement inhibition by hydroxychloroquine prevents placental and fetal brain abnormalities in antiphospholipid syndrome.

PubMed

Bertolaccini, Maria Laura; Contento, Gregorio; Lennen, Ross; Sanna, Giovanni; Blower, Philip J; Ma, Michelle T; Sunassee, Kavitha; Girardi, Guillermina

2016-12-01

Placental ischemic disease and adverse pregnancy outcomes are frequently observed in patients with antiphospholipid syndrome (APS). Despite the administration of conventional antithrombotic treatment a significant number of women continue to experience adverse pregnancy outcomes, with uncertain prevention and management. Efforts to develop effective pharmacological strategies for refractory obstetric APS cases will be of significant clinical benefit for both mothers and fetuses. Although the antimalarial drug, hydroxychloroquine (HCQ) is increasingly used to treat pregnant women with APS, little is known about its efficacy and mechanism of action of HCQ. Because complement activation plays a crucial and causative role in placental ischemia and abnormal fetal brain development in APS we hypothesised that HCQ prevents these pregnancy complications through inhibition of complement activation. Using a mouse model of obstetric APS that closely resembles the clinical condition, we found that HCQ prevented fetal death and the placental metabolic changes -measured by proton magnetic resonance spectroscopy in APS-mice. Using 111 In labelled antiphospholipid antibodies (aPL) we identified the placenta and the fetal brain as the main organ targets in APS-mice. Using this same method, we found that HCQ does not inhibit aPL binding to tissues as was previously suggested from in vitro studies. While HCQ did not affect aPL binding to fetal brain it prevented fetal brain abnormal cortical development. HCQ prevented complement activation in vivo and in vitro. Complement C5a levels in serum samples from APS patients and APS-mice were lower after treatment with HCQ while the antibodies titres remained unchanged. HCQ prevented not only placental insufficiency but also abnormal fetal brain development in APS. By inhibiting complement activation, HCQ might also be an effective antithrombotic therapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Coating of human decay accelerating factor (hDAF) onto medical devices to improve biocompatibility.

PubMed

Watkins, N J; Braidley, P; Bray, C J; Savill, C M; White, D J

1997-12-01

In passing blood through an artificial circulatory system, the blood is exposed to surfaces that result in activation of the complement system. The consequences of the activation of complement can be extremely serious for the patient ranging from mild discomfort to respiratory distress and even anaphylaxis. An entirely novel approach was to express recombinant GPI anchored human decay accelerating factor (hDAF) using the baculovirus system and then coat the recombinant protein onto the surfaces of these materials to reduce complement activation. Expression of hDAF in Sf9 cells was shown by ELISA, FACS analysis, and Western blot. Functional activity was tested by CH50 assay. For the coating experiments a small scale model of a cardiovascular bypass circuit constructed from COBE tubing was used. hDAF was either coated onto the circuit using adsorption or covalently linked via the photoreactive crosslinker, p-azidobenzoyl hydrazide. After coating, heparinised human blood was pumped around the circuit and samples were collected into EDTA collection tubes at different time points. Complement activation was measured using a Quidel C3a-des-arg EIA. The photolinked circuits gave a reduction in C3a production of 20-50%, compared to 10-20% seen with an absorbed hDAF circuit. Furthermore, the inhibition of complement was seen over the whole time scale of the photolinked circuit, 60-90 min, whilst in the adsorbed circuit inhibition was not seen to a significant degree after 60 min. The time scale of a standard cardiac bypass is 45-90 min, therefore, the photolinked circuit results are encouraging, as significant inhibition of complement activation is seen within this time frame.

Identification of novel candidate maternal serum protein markers for Down syndrome by integrated proteomic and bioinformatic analysis.

PubMed

Kang, Yuan; Dong, Xinran; Zhou, Qiongjie; Zhang, Ying; Cheng, Yan; Hu, Rong; Su, Cuihong; Jin, Hong; Liu, Xiaohui; Ma, Duan; Tian, Weidong; Li, Xiaotian

2012-03-01

This study aimed to identify candidate protein biomarkers from maternal serum for Down syndrome (DS) by integrated proteomic and bioinformatics analysis. A pregnancy DS group of 18 women and a control group with the same number were prepared, and the maternal serum proteins were analyzed by isobaric tags for relative and absolute quantitation and mass spectrometry, to identify DS differentially expressed maternal serum proteins (DS-DEMSPs). Comprehensive bioinformatics analysis was then employed to analyze DS-DEMSPs both in this paper and seven related publications. Down syndrome differentially expressed maternal serum proteins from different studies are significantly enriched with common Gene Ontology functions, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, transcription factor binding sites, and Pfam protein domains, However, the DS-DEMSPs are less functionally related to known DS-related genes. These evidences suggest that common molecular mechanisms induced by secondary effects may be present upon DS carrying. A simple scoring scheme revealed Alpha-2-macroglobulin, Apolipoprotein A1, Apolipoprotein E, Complement C1s subcomponent, Complement component 5, Complement component 8, alpha polypeptide, Complement component 8, beta polypeptide and Fibronectin as potential DS biomarkers. The integration of proteomics and bioinformatics studies provides a novel approach to develop new prenatal screening methods for noninvasive yet accurate diagnosis of DS. Copyright © 2012 John Wiley & Sons, Ltd.

Studies of Dynamic Protein-Protein Interactions in Bacteria Using Renilla Luciferase Complementation Are Undermined by Nonspecific Enzyme Inhibition

PubMed Central

Hatzios, Stavroula K.; Ringgaard, Simon; Davis, Brigid M.; Waldor, Matthew K.

2012-01-01

The luciferase protein fragment complementation assay is a powerful tool for studying protein-protein interactions. Two inactive fragments of luciferase are genetically fused to interacting proteins, and when these two proteins interact, the luciferase fragments can reversibly associate and reconstitute enzyme activity. Though this technology has been used extensively in live eukaryotic cells, split luciferase complementation has not yet been applied to studies of dynamic protein-protein interactions in live bacteria. As proof of concept and to develop a new tool for studies of bacterial chemotaxis, fragments of Renilla luciferase (Rluc) were fused to the chemotaxis-associated response regulator CheY3 and its phosphatase CheZ in the enteric pathogen Vibrio cholerae. Luciferase activity was dependent on the presence of both CheY3 and CheZ fusion proteins, demonstrating the specificity of the assay. Furthermore, enzyme activity was markedly reduced in V. cholerae chemotaxis mutants, suggesting that this approach can measure defects in chemotactic signaling. However, attempts to measure changes in dynamic CheY3-CheZ interactions in response to various chemoeffectors were undermined by nonspecific inhibition of the full-length luciferase. These observations reveal an unexpected limitation of split Rluc complementation that may have implications for existing data and highlight the need for great caution when evaluating small molecule effects on dynamic protein-protein interactions using the split luciferase technology. PMID:22905225

Studies of dynamic protein-protein interactions in bacteria using Renilla luciferase complementation are undermined by nonspecific enzyme inhibition.

PubMed

Hatzios, Stavroula K; Ringgaard, Simon; Davis, Brigid M; Waldor, Matthew K

2012-01-01

The luciferase protein fragment complementation assay is a powerful tool for studying protein-protein interactions. Two inactive fragments of luciferase are genetically fused to interacting proteins, and when these two proteins interact, the luciferase fragments can reversibly associate and reconstitute enzyme activity. Though this technology has been used extensively in live eukaryotic cells, split luciferase complementation has not yet been applied to studies of dynamic protein-protein interactions in live bacteria. As proof of concept and to develop a new tool for studies of bacterial chemotaxis, fragments of Renilla luciferase (Rluc) were fused to the chemotaxis-associated response regulator CheY3 and its phosphatase CheZ in the enteric pathogen Vibrio cholerae. Luciferase activity was dependent on the presence of both CheY3 and CheZ fusion proteins, demonstrating the specificity of the assay. Furthermore, enzyme activity was markedly reduced in V. cholerae chemotaxis mutants, suggesting that this approach can measure defects in chemotactic signaling. However, attempts to measure changes in dynamic CheY3-CheZ interactions in response to various chemoeffectors were undermined by nonspecific inhibition of the full-length luciferase. These observations reveal an unexpected limitation of split Rluc complementation that may have implications for existing data and highlight the need for great caution when evaluating small molecule effects on dynamic protein-protein interactions using the split luciferase technology.

Glucose-6-Phosphate Dehydrogenase Deficiency Mimicking Atypical Hemolytic Uremic Syndrome.

PubMed

Walsh, Patrick R; Johnson, Sally; Brocklebank, Vicky; Salvatore, Jacobo; Christian, Martin; Kavanagh, David

2018-02-01

A 4-year-old boy presented with nonimmune hemolysis, thrombocytopenia, and acute kidney injury. Investigations for an underlying cause failed to identify a definitive cause and a putative diagnosis of complement-mediated atypical hemolytic uremic syndrome (aHUS) was made. The patient was started initially on plasma exchange and subsequently eculizumab therapy, after which his kidney function rapidly improved. While on eculizumab therapy, despite adequate complement blockade, he presented 2 more times with hemolytic anemia and thrombocytopenia, but without renal involvement. Genetic analysis did not uncover a mutation in any known aHUS gene (CFH, CFI, CFB, C3, CD46, THBD, INF2, and DGKE) and anti-factor H antibodies were undetectable. Whole-exome sequencing was undertaken to identify a cause for the eculizumab resistance. This revealed a pathogenic variant in G6PD (glucose-6-phosphate dehydrogenase), which was confirmed by functional analysis demonstrating decreased erythrocyte G6PD activity. Eculizumab therapy was withdrawn. Complement-mediated aHUS is a diagnosis of exclusion and this case highlights the diagnostic difficulty that remains without an immediately available biomarker for confirmation. This case of G6PD deficiency presented with a phenotype clinically indistinguishable from complement-mediated aHUS. We recommend that G6PD deficiency be included in the differential diagnosis of patients presenting with aHUS and suggest measuring erythrocyte G6PD concentrations in these patients. Copyright © 2017. Published by Elsevier Inc.

Crystal structures of the Erp protein family members ErpP and ErpC from Borrelia burgdorferi reveal the reason for different affinities for complement regulator factor H.

PubMed

Brangulis, Kalvis; Petrovskis, Ivars; Kazaks, Andris; Akopjana, Inara; Tars, Kaspars

2015-05-01

Borrelia burgdorferi is the causative agent of Lyme disease, which can be acquired after the bite of an infected Ixodes tick. As a strategy to resist the innate immunity and to successfully spread and proliferate, B. burgdorferi expresses a set of outer membrane proteins that are capable of binding complement regulator factor H (CFH), factor H-like protein 1 (CFHL-1) and factor H-related proteins (CFHR) to avoid complement-mediated killing. B. burgdorferi B31 contains three proteins that belong to the Erp (OspE/F-related) protein family and are capable of binding CFH and some CFHRs, namely ErpA, ErpC and ErpP. We have determined the crystal structure of ErpP at 2.53Å resolution and the crystal structure of ErpC at 2.15Å resolution. Recently, the crystal structure of the Erp family member OspE from B. burgdorferi N40 was determined in complex with CFH domains 19-20, revealing the residues involved in the complex formation. Despite the high sequence conservation between ErpA, ErpC, ErpP and the homologous protein OspE (78-80%), the affinity for CFH and CFHRs differs markedly among the Erp family members, suggesting that ErpC may bind only CFHRs but not CFH. A comparison of the binding site in OspE with those of ErpC and ErpP revealed that the extended loop region, which is only observed in the potential binding site of ErpC, plays an important role by preventing the binding of CFH. These results can explain the inability of ErpC to bind CFH, whereas ErpP and ErpA still possess the ability to bind CFH. Copyright © 2015 Elsevier B.V. All rights reserved.

Transcriptional profiling reveals that C5a alters microRNA in brain endothelial cells

PubMed Central

Eadon, Michael T; Jacob, Alexander; Cunningham, Patrick N; Quigg, Richard J; Garcia, Joe G N; Alexander, Jessy J

2014-01-01

Blood–brain barrier (BBB) disturbance is a crucial occurrence in many neurological diseases, including systemic lupus erythematosus (SLE). Our previous studies showed that experimental lupus serum altered the integrity of the mouse brain endothelial layer, an important constituent of the BBB. Complement activation occurs in lupus with increased circulating complement components. Using a genomics approach, we identified the microRNA (miRNA) altered in mouse brain endothelial cells (bEnd3) by lupus serum and the complement protein, C5a. Of the 318 miRNA evaluated, 23 miRNAs were altered by lupus serum and 32 were altered by C5a alone compared with controls. Seven miRNAs (P < 0·05) were differentially expressed by both treatments: mmu-miR-133a*, mmu-miR-193*, mmu-miR-26b, mmu-miR-28*, mmu-miR-320a, mmu-miR-423-3p and mmu-miR-509-5p. The microarray results were validated by quantitative RT-PCR. In line with the in vitro results, expression of miR-26b and miR-28* were also significantly up-regulated in lupus mouse brain which was reduced by C5a receptor inhibition. Target prediction analysis revealed miR gene targets encoding components involved in inflammation, matrix arrangement, and apoptosis, pathways known to play important roles in central nervous system lupus. Our findings suggest that the miRNAs reported in this study may represent novel therapeutic targets in central nervous system lupus and other similar neuroinflammatory settings. PMID:24801999

Transcriptional profiling reveals that C5a alters microRNA in brain endothelial cells.

PubMed

Eadon, Michael T; Jacob, Alexander; Cunningham, Patrick N; Quigg, Richard J; Garcia, Joe G N; Alexander, Jessy J

2014-11-01

Blood-brain barrier (BBB) disturbance is a crucial occurrence in many neurological diseases, including systemic lupus erythematosus (SLE). Our previous studies showed that experimental lupus serum altered the integrity of the mouse brain endothelial layer, an important constituent of the BBB. Complement activation occurs in lupus with increased circulating complement components. Using a genomics approach, we identified the microRNA (miRNA) altered in mouse brain endothelial cells (bEnd3) by lupus serum and the complement protein, C5a. Of the 318 miRNA evaluated, 23 miRNAs were altered by lupus serum and 32 were altered by C5a alone compared with controls. Seven miRNAs (P < 0 · 05) were differentially expressed by both treatments: mmu-miR-133a*, mmu-miR-193*, mmu-miR-26b, mmu-miR-28*, mmu-miR-320a, mmu-miR-423-3p and mmu-miR-509-5p. The microarray results were validated by quantitative RT-PCR. In line with the in vitro results, expression of miR-26b and miR-28* were also significantly up-regulated in lupus mouse brain which was reduced by C5a receptor inhibition. Target prediction analysis revealed miR gene targets encoding components involved in inflammation, matrix arrangement, and apoptosis, pathways known to play important roles in central nervous system lupus. Our findings suggest that the miRNAs reported in this study may represent novel therapeutic targets in central nervous system lupus and other similar neuroinflammatory settings. © 2014 John Wiley & Sons Ltd.

Characterization of the gene encoding component C3 of the complement system from the spider Loxosceles laeta venom glands: Phylogenetic implications.

PubMed

Myamoto, D T; Pidde-Queiroz, G; Pedroso, A; Gonçalves-de-Andrade, R M; van den Berg, C W; Tambourgi, D V

2016-09-01

A transcriptome analysis of the venom glands of the spider Loxosceles laeta, performed by our group, in a previous study (Fernandes-Pedrosa et al., 2008), revealed a transcript with a sequence similar to the human complement component C3. Here we present the analysis of this transcript. cDNA fragments encoding the C3 homologue (Lox-C3) were amplified from total RNA isolated from the venom glands of L. laeta by RACE-PCR. Lox-C3 is a 5178 bps cDNA sequence encoding a 190kDa protein, with a domain configuration similar to human C3. Multiple alignments of C3-like proteins revealed two processing sites, suggesting that Lox-C3 is composed of three chains. Furthermore, the amino acids consensus sequences for the thioester was found, in addition to putative sequences responsible for FB binding. The phylogenetic analysis showed that Lox-C3 belongs to the same group as two C3 isoforms from the spider Hasarius adansoni (Family Salcitidae), showing 53% homology with these. This is the first characterization of a Loxosceles cDNA sequence encoding a human C3 homologue, and this finding, together with our previous finding of the expression of a FB-like molecule, suggests that this spider species also has a complement system. This work will help to improve our understanding of the innate immune system in these spiders and the ancestral structure of C3. Copyright © 2016 Elsevier GmbH. All rights reserved.

A mutational approach for the detection of genetic factors affecting seed size in maize.

PubMed

Sangiorgio, Stefano; Carabelli, Laura; Gabotti, Damiano; Manzotti, Priscilla Sofia; Persico, Martina; Consonni, Gabriella; Gavazzi, Giuseppe

2016-12-01

Genes influencing seed size. The designation emp (empty pericarp) refers to a group of defective kernel mutants that exhibit a drastic reduction in endosperm tissue production. They allow the isolation of genes controlling seed development and affecting seed size. Nine independently isolated emp mutants have been analyzed in this study and in all cases longitudinal sections of mature seeds revealed the absence of morphogenesis in the embryo proper, an observation that correlates with their failure to germinate. Complementation tests with the nine emp mutants, crossed inter se in all pairwise combinations, identified complementing and non-complementing pairs in the F 1 progenies. Data were then validated in the F 2 /F 3 generations. Mutant chromosomal location was also established. Overall our study has identified two novel emp genes and a novel allele at the previously identified emp4 gene. The introgression of single emp mutants in a different genetic background revealed the existence of a cryptic genetic variation (CGV) recognizable as a variable increase in the endosperm tissue. The unmasking of CGV by introducing single mutants in different genetic backgrounds is the result of the interaction of the emp mutants with a suppressor that has no obvious phenotype of its own and is present in the genetic background of the inbred lines into which the emp mutants were transferred. On the basis of these results, emp mutants could be used as tools for the detection of genetic factors that enhance the amount of endosperm tissue in the maize kernel and which could thus become valuable targets to exploit in future breeding programs.

Thermal control surfaces on the MSFC LDEF experiments

NASA Technical Reports Server (NTRS)

Wilkes, Donald R.; Whitaker, Ann F.; Zwiener, James M.; Linton, Roger C.; Shular, David; Peters, Palmer N.; Gregory, John C.

1992-01-01

There were five Marshall Space Flight Center (MSFC) experiments on the LDEF. Each of those experiments carried thermal control surfaces either as test samples or as operational surfaces. These materials experienced varying degrees of mechanical and optical damage. Some materials were virtually unchanged by the extended exposure while others suffered extensive degradation. The synergistic effects due to the constituents of the space environment are evident in the diversity of these material changes. The sample complement for the MSFC experiments is described along with results of the continuing analyses efforts.

Isolation and Characterization of Sex-Linked Female-Sterile Mutants in DROSOPHILA MELANOGASTER

PubMed Central

Gans, Madeleine; Audit, Claudie; Masson, Michele

1975-01-01

The purpose of the experiments described was to identify X chromosome genes functioning mainly or exclusively during oogenesis. Two mutagenesis experiments were carried out with ethyl methane sulfonate. Following treatment inducing 60% lethals, 9% of the treated X chromosomes carried a female sterility mutation which did not otherwise seriously affect viability. Among —95 isolated mutants, 19 were heat-sensitive and 5 cold-sensitive. The mutants have been classified as follows: I (16 mutants; 12 complementation groups): the females laid few or no eggs; the defect concerned either ovulation or oogenesis. II (37 mutants; 18 complementation groups): the female laid morphologically abnormal eggs, often with increased membrane permeability. III A (13 mutants; at least 8 complementation groups): the homozygous females were sterile if mated to mutant males; their progeny (homo- and hemizygous) died at a late embryonic stage (11 mutants), at the larval stage (1 mutant) or at the pupal stage (1 mutant). However fertility was partly restored by breeding to wild-type males as shown by survival of some heterozygous descendants. III B (29 mutants; 22 complementation groups): the fertility of the females was not restored by breeding to a wild-type male. Most of the eggs of 13 of the mutants died at a late stage of embryogenesis. The eggs of the others ceased development earlier or, perhaps, remained unfertilized. The distribution of the number of mutants per complementation group led to an estimation of a total of about 150 X-linked genes involved in female fertility. The females of three mutants, heat-sensitive and totally sterile at 29°, produced at a lower temperature descendants morphologically abnormal or deprived of germ cells. Three other mutants not described in detail showed a reduction in female fertility with many descendants lacking germ cells. A desirable mutant which was not recovered was one with normal fertile females producing descendants which, regardless of their genotype, bore specific morphological abnormalities. The value of the mutants isolated for analysis of the complex processes leading to egg formation and initiation of development is discussed. PMID:814037

Use of eculizumab and plasma exchange in successful combined liver-kidney transplantation in a case of atypical HUS associated with complement factor H mutation.

PubMed

Tran, Ha; Chaudhuri, Abanti; Concepcion, Waldo; Grimm, Paul C

2014-03-01

Atypical hemolytic uremic syndrome (aHUS) evolves into end-stage renal failure in nearly half of affected patients and is associated with defective regulation of the alternative complement pathway. Patients with a complement factor H (CFH) mutation have a 30-100% risk of graft loss due to aHUS recurrence or graft thrombosis. Since CFH is produced predominantly by the liver, combined liver-kidney transplant is a curative treatment option. One major unexpected risk includes liver failure secondary to uncontrolled complement activation. We report a successful combined liver-kidney transplantation with perioperative plasma exchange and use of the humanized anti-C5 monoclonal antibody eculizumab. An 11-month-old female presented with oliguric renal failure after 3 weeks of flu-like symptoms in the absence of diarrhea. Following the identification of Escherichia coli 0157:H7 in her stool, she was discharged home on peritoneal dialysis with a diagnosis of Shiga toxin-associated HUS. Three months later, she developed severe anemia, thrombocytopenia, and neurological involvement. aHUS was diagnosed and confirmed, and genetic testing revealed a mutation in CFH SCR20. Once donor organs became available, she received preoperative plasma exchange followed by eculizumab infusion with intra-operative fresh frozen plasma prior to combined liver-kidney transplant. At 19 months post-transplant, she continues to have excellent allograft and liver function without signs of disease recurrence. Perioperative use of eculizumab in conjunction with plasma exchange during simultaneous liver-kidney transplant can be used to inhibit terminal complement activity, thereby optimizing successful transplantation by reducing the risk of graft thrombosis.

Substantial Loss of Conserved and Gain of Novel MicroRNA Families in Flatworms

PubMed Central

Fromm, Bastian; Worren, Merete Molton; Hahn, Christoph; Hovig, Eivind; Bachmann, Lutz

2013-01-01

Recent studies on microRNA (miRNA) evolution focused mainly on the comparison of miRNA complements between animal clades. However, evolution of miRNAs within such groups is poorly explored despite the availability of comparable data that in some cases lack only a few key taxa. For flatworms (Platyhelminthes), miRNA complements are available for some free-living flatworms and all major parasitic lineages, except for the Monogenea. We present the miRNA complement of the monogenean flatworm Gyrodactylus salaris that facilitates a comprehensive analysis of miRNA evolution in Platyhelminthes. Using the newly designed bioinformatics pipeline miRCandRef, the miRNA complement was disentangled from next-generation sequencing of small RNAs and genomic DNA without a priori genome assembly. It consists of 39 miRNA hairpin loci of conserved miRNA families, and 22 novel miRNAs. A comparison with the miRNA complements of Schmidtea mediterranea (Turbellaria), Schistosoma japonicum (Trematoda), and Echinococcus granulosus (Cestoda) reveals a substantial loss of conserved bilaterian, protostomian, and lophotrochozoan miRNAs. Eight of the 46 expected conserved miRNAs were lost in all flatworms, 16 in Neodermata and 24 conserved miRNAs could not be detected in the cestode and the trematode. Such a gradual loss of miRNAs has not been reported before for other animal phyla. Currently, little is known about miRNAs in Platyhelminthes, and for the majority of the lost miRNAs there is no prediction of function. As suggested earlier they might be related to morphological simplifications. The presence and absence of 153 conserved miRNAs was compared for platyhelminths and 32 other metazoan taxa. Phylogenetic analyses support the monophyly of Platyhelminthes (Turbellaria + Neodermata [Monogenea {Trematoda + Cestoda}]). PMID:24025793

Liftoff of STS-67 Space Shuttle Endeavour

NASA Technical Reports Server (NTRS)

1995-01-01

Carrying a crew of seven and a complement of astronomic experiments, the Space Shuttle Endeavour embarks on NASA's longest Shuttle flight to date. Endeavour's liftoff from Launch Pad 39A occurred at 1:38:13 a.m. (EST), March 2, 1995.

Tools for Systematic Identification of Cross-Disciplinary Research Relevant to Exploration Missions

NASA Astrophysics Data System (ADS)

Shelhamer, M.; Mindock, J. A.

2018-02-01

A Contributing Factor Map and text analytics on articles and reports can identify connections between major factors contributing to health and performance on Deep Space Gateway missions. Connections suggest experiment complements to maximize use of these flights.

Gender Development

ERIC Educational Resources Information Center

Owen Blakemore, Judith E.; Berenbaum, Sheri A.; Liben, Lynn S.

2008-01-01

This new text offers a unique developmental focus on gender. Gender development is examined from infancy through adolescence, integrating biological, socialization, and cognitive perspectives. The book's current empirical focus is complemented by a lively and readable style that includes anecdotes about children's everyday experiences. The book's…

University of Wisconsin Cirrus Remote Sensing Pilot Experiment

NASA Technical Reports Server (NTRS)

Ackerman, Steven A.; Eloranta, Ed W.; Grund, Chris J.; Knuteson, Robert O.; Revercomb, Henry E.; Smith, William L.; Wylie, Donald P.

1993-01-01

During the period of 26 October 1989 through 6 December 1989 a unique complement of measurements was made at the University of Wisconsin-Madison to study the radiative properties of cirrus clouds. Simultaneous observations were obtained from a scanning lidar, two interferometers, a high spectral resolution lidar, geostationary and polar orbiting satellites, radiosonde launches, and a whole-sky imager. This paper describes the experiment, the instruments deployed, and, as an example, the data collected during one day of the experiment.

STS-37 Gamma Ray Observatory (GRO) grappled by RMS

NASA Image and Video Library

1991-04-07

Backdropped against the Earth's surface, the Gamma Ray Observatory (GRO) with its solar array (SA) panels deployed is grappled by the remote manipulator system (RMS) during STS-37 systems checkout. GRO's four complement instruments are visible: the Energetic Gamma Ray Experiment Telescope (EGRET) (at the bottom); the Imaging Compton Telescope (COMPTEL) (center); the Oriented Scintillation Spectrometer Experiment (OSSE) (top); and Burst and Transient Source Experiment (BATSE) (on four corners). The view was taken by STS-37 crew through an aft flight deck overhead window.

Cell Differentiation during Sexual Development of the Fungus Sordaria macrospora Requires ATP Citrate Lyase Activity

PubMed Central

Nowrousian, Minou; Masloff, Sandra; Pöggeler, Stefanie; Kück, Ulrich

1999-01-01

During sexual development, mycelial cells from most filamentous fungi differentiate into typical fruiting bodies. Here, we describe the isolation and characterization of the Sordaria macrospora developmental mutant per5, which exhibits a sterile phenotype with defects in fruiting body maturation. Cytological investigations revealed that the mutant strain forms only ascus precursors without any mature spores. Using an indexed cosmid library, we were able to complement the mutant to fertility by DNA-mediated transformation. A single cosmid clone, carrying a 3.5-kb region able to complement the mutant phenotype, has been identified. Sequencing of the 3.5-kb region revealed an open reading frame of 2.1 kb interrupted by a 66-bp intron. The predicted polypeptide (674 amino acids) shows significant homology to eukaryotic ATP citrate lyases (ACLs), with 62 to 65% amino acid identity, and the gene was named acl1. The molecular mass of the S. macrospora ACL1 polypeptide is 73 kDa, as was verified by Western blot analysis with a hemagglutinin (HA) epitope-tagged ACL1 polypeptide. Immunological in situ detection of the HA-tagged polypeptide demonstrated that ACL is located within the cytosol. Sequencing of the mutant acl1 gene revealed a 1-nucleotide transition within the coding region, resulting in an amino acid substitution within the predicted polypeptide. Further evidence that ACL1 is essential for fruiting body maturation comes from experiments in which truncated and mutated versions of the acl1 gene were used for transformation. None of these copies was able to reconstitute the fertile phenotype in transformed per5 recipient strains. ACLs are usually involved in the formation of cytosolic acetyl coenzyme A (acetyl-CoA), which is used for the biosynthesis of fatty acids and sterols. Protein extracts from the mutant strain showed a drastic reduction in enzymatic activity compared to values obtained from the wild-type strain. Investigation of the time course of ACL expression suggests that ACL is specifically induced at the beginning of the sexual cycle and produces acetyl-CoA, which most probably is a prerequisite for fruiting body formation during later stages of sexual development. We discuss the contribution of ACL activity to the life cycle of S. macrospora. PMID:9858569

Cell differentiation during sexual development of the fungus Sordaria macrospora requires ATP citrate lyase activity.

PubMed

Nowrousian, M; Masloff, S; Pöggeler, S; Kück, U

1999-01-01

During sexual development, mycelial cells from most filamentous fungi differentiate into typical fruiting bodies. Here, we describe the isolation and characterization of the Sordaria macrospora developmental mutant per5, which exhibits a sterile phenotype with defects in fruiting body maturation. Cytological investigations revealed that the mutant strain forms only ascus precursors without any mature spores. Using an indexed cosmid library, we were able to complement the mutant to fertility by DNA-mediated transformation. A single cosmid clone, carrying a 3.5-kb region able to complement the mutant phenotype, has been identified. Sequencing of the 3.5-kb region revealed an open reading frame of 2.1 kb interrupted by a 66-bp intron. The predicted polypeptide (674 amino acids) shows significant homology to eukaryotic ATP citrate lyases (ACLs), with 62 to 65% amino acid identity, and the gene was named acl1. The molecular mass of the S. macrospora ACL1 polypeptide is 73 kDa, as was verified by Western blot analysis with a hemagglutinin (HA) epitope-tagged ACL1 polypeptide. Immunological in situ detection of the HA-tagged polypeptide demonstrated that ACL is located within the cytosol. Sequencing of the mutant acl1 gene revealed a 1-nucleotide transition within the coding region, resulting in an amino acid substitution within the predicted polypeptide. Further evidence that ACL1 is essential for fruiting body maturation comes from experiments in which truncated and mutated versions of the acl1 gene were used for transformation. None of these copies was able to reconstitute the fertile phenotype in transformed per5 recipient strains. ACLs are usually involved in the formation of cytosolic acetyl coenzyme A (acetyl-CoA), which is used for the biosynthesis of fatty acids and sterols. Protein extracts from the mutant strain showed a drastic reduction in enzymatic activity compared to values obtained from the wild-type strain. Investigation of the time course of ACL expression suggests that ACL is specifically induced at the beginning of the sexual cycle and produces acetyl-CoA, which most probably is a prerequisite for fruiting body formation during later stages of sexual development. We discuss the contribution of ACL activity to the life cycle of S. macrospora.

Predation on Japanese quail vs. house sparrow eggs in artificial nests: small eggs reveal small predators

Treesearch

Thomas J. Maier; Richard M. DeGraaf

2000-01-01

Nest predation studies frequently use eggs such as Japanese Quail (Coturnix japonica) to identify potential predators of Neotropical migrants' eggs, but such eggs may be too large or thick-shelled to identify the full complement of potential predators. We compared predation events and predators of Japanese Quail and smaller House Sparrow (

The wheat Sr50 gene reveals rich diversity at a cereal disease resistance locus

USDA-ARS?s Scientific Manuscript database

We identify the wheat stem rust resistance gene Sr50 by physical mapping, mutation and complementation as homologous to barley Mla encoding a Coiled-Coil-Nucleotide-Binding-Leucine-Rich Repeat (CC-NB-LRR) protein. We show that Sr50 confers a unique resistance specificity, different from Sr31 and oth...

Molecular interactions of ROOTLESS CONCERNING CROWN AND SEMINAL ROOTS, a LOB domain protein regulating shoot-borne root initiation in maize (Zea mays L.)

PubMed Central

Majer, Christine; Xu, Changzheng; Berendzen, Kenneth W.; Hochholdinger, Frank

2012-01-01

Rootless concerning crown and seminal roots (Rtcs) encodes a LATERAL ORGAN BOUNDARIES domain (LBD) protein that regulates shoot-borne root initiation in maize (Zea mays L.). GREEN FLUORESCENT PROTEIN (GFP)-fusions revealed RTCS localization in the nucleus while its paralogue RTCS-LIKE (RTCL) was detected in the nucleus and cytoplasm probably owing to an amino acid exchange in a nuclear localization signal. Moreover, enzyme-linked immunosorbent assay (ELISA) experiments demonstrated that RTCS primarily binds to LBD DNA motifs. RTCS binding to an LBD motif in the promoter of the auxin response factor (ARF) ZmArf34 and reciprocally, reciprocal ZmARF34 binding to an auxin responsive element motif in the promoter of Rtcs was shown by electrophoretic mobility shift assay experiments. In addition, comparative qRT-PCR of wild-type versus rtcs coleoptilar nodes suggested RTCS-dependent activation of ZmArf34 expression. Consistently, luciferase reporter assays illustrated the capacity of RTCS, RTCL and ZmARF34 to activate downstream gene expression. Finally, RTCL homo- and RTCS/RTCL hetero-interaction were demonstrated in yeast-two-hybrid and bimolecular fluorescence complementation experiments, suggesting a role of these complexes in downstream gene regulation. In summary, the data provide novel insights into the molecular interactions resulting in crown root initiation in maize. PMID:22527397

Molecular interactions of ROOTLESS CONCERNING CROWN AND SEMINAL ROOTS, a LOB domain protein regulating shoot-borne root initiation in maize (Zea mays L.).

PubMed

Majer, Christine; Xu, Changzheng; Berendzen, Kenneth W; Hochholdinger, Frank

2012-06-05

Rootless concerning crown and seminal roots (Rtcs) encodes a LATERAL ORGAN BOUNDARIES domain (LBD) protein that regulates shoot-borne root initiation in maize (Zea mays L.). GREEN FLUORESCENT PROTEIN (GFP)-fusions revealed RTCS localization in the nucleus while its paralogue RTCS-LIKE (RTCL) was detected in the nucleus and cytoplasm probably owing to an amino acid exchange in a nuclear localization signal. Moreover, enzyme-linked immunosorbent assay (ELISA) experiments demonstrated that RTCS primarily binds to LBD DNA motifs. RTCS binding to an LBD motif in the promoter of the auxin response factor (ARF) ZmArf34 and reciprocally, reciprocal ZmARF34 binding to an auxin responsive element motif in the promoter of Rtcs was shown by electrophoretic mobility shift assay experiments. In addition, comparative qRT-PCR of wild-type versus rtcs coleoptilar nodes suggested RTCS-dependent activation of ZmArf34 expression. Consistently, luciferase reporter assays illustrated the capacity of RTCS, RTCL and ZmARF34 to activate downstream gene expression. Finally, RTCL homo- and RTCS/RTCL hetero-interaction were demonstrated in yeast-two-hybrid and bimolecular fluorescence complementation experiments, suggesting a role of these complexes in downstream gene regulation. In summary, the data provide novel insights into the molecular interactions resulting in crown root initiation in maize.

Evolution and Persistence of the Resistance-Associated Substitutions of Hepatitis C Virus after Direct-Acting Antiviral Treatment Failures.

PubMed

Jeong, Yechan; Jin, Bora; Lee, Hye Won; Park, Hye Jung; Park, Jun Yong; Kim, Do Young; Han, Kwang-Hyub; Ahn, Sang Hoon; Kim, Seungtaek

2018-05-16

Daclatasvir plus asunaprevir (DCV+ASV) treatment is an all-oral direct-acting antiviral (DAA) therapy for the genotype 1b HCV-infected patients. In this study, we investigated how resistance-associated substitutions (RASs) evolved after treatment failures and assessed the effect of those substitutions on viral fitness. Sequencing of NS5A and NS3 revealed typical RASs after treatment failures. Interestingly, the RASs of NS3 reverted to the wild-type amino acid within one year after treatment failures. However, the RASs of NS5A were stable and did not change. The effect of NS5A and NS3 RASs on viral RNA replication was assessed after mutagenic substitution in the genotype 1b HCV RNA. Among the single substitutions, the effect of D168V was more substantial than the others and the effect of the triple mutant combination (D168V+L31V+Y93H) was the most severe. The RAS at NS5A Y93 affected both viral RNA replication and virus production. Finally, the effect of trans-complementation of NS5A was demonstrated in our co-transfection experiments and these results suggest that such a trans-complementation effect of NS5A may help maintain the NS5A RASs for a long time even after cessation of the DAA treatment. In conclusion, the results from this investigation would help understand the emergence and persistence of RASs. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Analysis of tandem E-box motifs within human Complement receptor 2 (CR2/CD21) promoter reveals cell specific roles for RP58, E2A, USF and localized chromatin accessibility.

PubMed

Cruickshank, Mark N; Dods, James; Taylor, Rhonda L; Karimi, Mahdad; Fenwick, Emily J; Quail, Elizabeth A; Rea, Alexander J; Holers, V Michael; Abraham, Lawrence J; Ulgiati, Daniela

2015-07-01

Complement receptor 2 (CR2/CD21) plays an important role in the generation of normal B cell immune responses. As transcription appears to be the prime mechanism via which surface CR2/CD21 expression is controlled, understanding transcriptional regulation of this gene will have broader implications to B cell biology. Here we report opposing, cell-context specific control of CR2/CD21 promoter activity by tandem E-box elements, spaced 22 bp apart and within 70 bp of the transcription initiation site. We have identified E2A and USF transcription factors as binding to the distal and proximal E-box sites respectively in CR2-positive B-cells, at a site that is hypersensitive to restriction enzyme digestion compared to non-expressing K562 cells. However, additional unidentified proteins have also been found to bind these functionally important elements. By utilizing a proteomics approach we have identified a repressor protein, RP58, binding the distal E-box motif. Co-transfection experiments using RP58 overexpression constructs demonstrated a specific 10-fold repression of CR2/CD21 transcriptional activity mediated through the distal E-box repressor element. Taken together, our results indicate that repression of the CR2/CD21 promoter can occur through one of the E-box motifs via recruitment of RP58 and other factors to bring about a silenced chromatin context within CR2/CD21 non-expressing cells. Copyright © 2015 Elsevier Ltd. All rights reserved.

Polyreactive Antibodies Plus Complement Enhance the Phagocytosis of Cells Made Apoptotic by UV-Light or HIV

PubMed Central

Zhou, Zhao-hua; Wild, Teresa; Xiong, Ying; Sylvers, Peter; Zhang, Yahong; Zhang, Luxia; Wahl, Larry; Wahl, Sharon M.; Kozlowski, Steven; Notkins, Abner L.

2013-01-01

Polyreactive antibodies are a major component of the natural antibody repertoire and are capable of binding a variety of structurally unrelated antigens. Many of the properties attributed to natural antibodies, in fact, are turning out to be due to polyreactive antibodies. In humans, each day, billions of cells undergo apoptosis. In the present experiments, we show by ImageStream technology that although polyreactive antibodies do not bind to live T cells they bind to both the plasma membrane and cytoplasm of late apoptotic cells, fix complement, generate the anaphylatoxin C5a and increase by as much as 5 fold complement-mediated phagocytosis by macrophages. Of particular importance, T cells undergoing apoptosis following infection with HIV also bind polyreactive antibodies and are phagocytosed. We conclude that the polyreactive antibodies in the natural antibody repertoire contribute in a major way to the clearance of cells made apoptotic by a variety of natural and infectious processes. PMID:23881356

Towards memory-aware services and browsing through lifelogging sensing.

PubMed

Arcega, Lorena; Font, Jaime; Cetina, Carlos

2013-11-05

Every day we receive lots of information through our senses that is lost forever, because it lacked the strength or the repetition needed to generate a lasting memory. Combining the emerging Internet of Things and lifelogging sensors, we believe it is possible to build up a Digital Memory (Dig-Mem) in order to complement the fallible memory of people. This work shows how to realize the Dig-Mem in terms of interactions, affinities, activities, goals and protocols. We also complement this Dig-Mem with memory-aware services and a Dig-Mem browser. Furthermore, we propose a RFID Tag-Sharing technique to speed up the adoption of Dig-Mem. Experimentation reveals an improvement of the user understanding of Dig-Mem as time passes, compared to natural memories where the level of detail decreases over time.

Family members' narratives of lifespace: Mapping changes before and after a brain injury causing driving disruption.

PubMed

Liang, Phyllis; Liddle, Jacki; Fleming, Jennifer; Gustafsson, Louise

2016-06-01

Family members of a person with an acquired brain injury often provide transport assistance during driving disruption with potential impacts on their own travel and participation within the community. The geographic area in which people travel and conduct their activities is known as lifespace. This study aimed to describe the quantitative changes in family members' lifespace after brain injury and understand their subjective experiences through interacting with maps during narratives. Mapping was embedded within in-depth semi-structured interviews with 15 family members. Two sets of maps were generated per participant showing the number of travel locations before and after brain injury. In the interviews, participants reflected on the perceived meaning of lifespace change. Qualitative data were analysed using a narrative approach. Quantitative data from the mapping revealed an increase in travel locations for nine participants, a decrease for five, and no change for one participant. Data analysis revealed four typologies which complemented and enriched the quantitative data: (i) I will do everything for him or her; (ii) Trying to fit all in; (iii) We spend all our time together now; (iv) I need to also care for myself. The findings describe the change in family members' lifespace after taking on the driver role following acquired brain injury. This study highlights the importance of understanding both quantitative and qualitative aspects of lifespace. The subjective experiences and consequences of lifespace changes are different from the impact on individuals with health conditions. Mapping in an interview as a tool has potential clinical utility. © 2016 Occupational Therapy Australia.

The role of the PHP domain associated with DNA polymerase X from Thermus thermophilus HB8 in base excision repair.

PubMed

Nakane, Shuhei; Nakagawa, Noriko; Kuramitsu, Seiki; Masui, Ryoji

2012-11-01

Base excision repair (BER) is one of the most commonly used DNA repair pathways involved in genome stability. X-family DNA polymerases (PolXs) play critical roles in BER, especially in filling single-nucleotide gaps. In addition to a polymerase core domain, bacterial PolXs have a polymerase and histidinol phosphatase (PHP) domain with phosphoesterase activity which is also required for BER. However, the role of the PHP domain of PolX in bacterial BER remains unresolved. We found that the PHP domain of Thermus thermophilus HB8 PolX (ttPolX) functions as two types of phosphoesterase in BER, including a 3'-phosphatase and an apurinic/apyrimidinic (AP) endonuclease. Experiments using T. thermophilus HB8 cell lysates revealed that the majority of the 3'-phosphatase and AP endonuclease activities are attributable to the another phosphoesterase in T. thermophilus HB8, endonuclease IV (ttEndoIV). However, ttPolX possesses significant 3'-phosphatase activity in ΔttendoIV cell lysate, indicating possible complementation. Our experiments also reveal that there are only two enzymes that display the 3'-phosphatase activity in the T. thermophilus HB8 cell, ttPolX and ttEndoIV. Furthermore, phenotypic analysis of ΔttpolX, ΔttendoIV, and ΔttpolX/ΔttendoIV using hydrogen peroxide and sodium nitrite supports the hypothesis that ttPolX functions as a backup for ttEndoIV in BER. Copyright © 2012 Elsevier B.V. All rights reserved.

Ubiquitous Sensor Networking for Development (USN4D): an application to pollution monitoring.

PubMed

Bagula, Antoine; Zennaro, Marco; Inggs, Gordon; Scott, Simon; Gascon, David

2012-01-01

This paper presents a new Ubiquitous Sensor Network (USN) Architecture to be used in developing countries and reveals its usefulness by highlighting some of its key features. In complement to a previous ITU proposal, our architecture referred to as "Ubiquitous Sensor Network for Development (USN4D)" integrates in its layers features such as opportunistic data dissemination, long distance deployment and localisation of information to meet the requirements of the developing world. Besides describing some of the most important requirements for the sensor equipment to be used in a USN4D setting, we present the main features and experiments conducted using the "WaspNet" as one of the wireless sensor deployment platforms that meets these requirements. Furthermore, building upon "WaspNet" platform, we present an application to Air pollution Monitoring in the city of Cape Town, in South Africa as one of the first steps towards building community wireless sensor networks (CSN) in the developing world using off-the-shelf sensor equipment.

Comparing Simplification Strategies for the Skeletal Muscle Proteome

PubMed Central

Geary, Bethany; Young, Iain S.; Cash, Phillip; Whitfield, Phillip D.; Doherty, Mary K.

2016-01-01

Skeletal muscle is a complex tissue that is dominated by the presence of a few abundant proteins. This wide dynamic range can mask the presence of lower abundance proteins, which can be a confounding factor in large-scale proteomic experiments. In this study, we have investigated a number of pre-fractionation methods, at both the protein and peptide level, for the characterization of the skeletal muscle proteome. The analyses revealed that the use of OFFGEL isoelectric focusing yielded the largest number of protein identifications (>750) compared to alternative gel-based and protein equalization strategies. Further, OFFGEL led to a substantial enrichment of a different sub-population of the proteome. Filter-aided sample preparation (FASP), coupled to peptide-level OFFGEL provided more confidence in the results due to a substantial increase in the number of peptides assigned to each protein. The findings presented here support the use of a multiplexed approach to proteome characterization of skeletal muscle, which has a recognized imbalance in the dynamic range of its protein complement. PMID:28248220

Ubiquitous Sensor Networking for Development (USN4D): An Application to Pollution Monitoring

PubMed Central

Bagula, Antoine; Zennaro, Marco; Inggs, Gordon; Scott, Simon; Gascon, David

2012-01-01

This paper presents a new Ubiquitous Sensor Network (USN) Architecture to be used in developing countries and reveals its usefulness by highlighting some of its key features. In complement to a previous ITU proposal, our architecture referred to as “Ubiquitous Sensor Network for Development (USN4D)” integrates in its layers features such as opportunistic data dissemination, long distance deployment and localisation of information to meet the requirements of the developing world. Besides describing some of the most important requirements for the sensor equipment to be used in a USN4D setting, we present the main features and experiments conducted using the “WaspNet” as one of the wireless sensor deployment platforms that meets these requirements. Furthermore, building upon “WaspNet” platform, we present an application to Air pollution Monitoring in the city of Cape Town, in South Africa as one of the first steps towards building community wireless sensor networks (CSN) in the developing world using off-the-shelf sensor equipment. PMID:22368476

Co(II) Coordination in Prokaryotic Zinc Finger Domains as Revealed by UV-Vis Spectroscopy

PubMed Central

Sivo, Valeria; D'Abrosca, Gianluca; Russo, Luigi; Iacovino, Rosa; Pedone, Paolo Vincenzo; Fattorusso, Roberto

2017-01-01

Co(II) electronic configuration allows its use as a spectroscopic probe in UV-Vis experiments to characterize the metal coordination sphere that is an essential component of the functional structure of zinc-binding proteins and to evaluate the metal ion affinities of these proteins. Here, exploiting the capability of the prokaryotic zinc finger to use different combinations of residues to properly coordinate the structural metal ion, we provide the UV-Vis characterization of Co(II) addition to Ros87 and its mutant Ros87_C27D which bears an unusual CysAspHis2 coordination sphere. Zinc finger sites containing only one cysteine have been infrequently characterized. We show for the CysAspHis2 coordination an intense d-d transition band, blue-shifted with respect to the Cys2His2 sphere. These data complemented by NMR and CD data demonstrate that the tetrahedral geometry of the metal site is retained also in the case of a single-cysteine coordination sphere. PMID:29386985

Toblerols: Cyclopropanol-Containing Polyketide Modulators of Antibiosis in Methylobacteria.

PubMed

Ueoka, Reiko; Bortfeld-Miller, Miriam; Morinaka, Brandon I; Vorholt, Julia A; Piel, Jörn

2018-01-22

Trans-AT polyketide synthases (PKSs) are a family of biosynthetically versatile modular type I PKSs that generate bioactive polyketides of impressive structural diversity. In this study, we detected, in the genome of several bacteria a cryptic, architecturally unusual trans-AT PKS gene cluster which eluded automated PKS prediction. Genomic mining of one of these strains, the model methylotroph Methylobacterium extorquens AM1, revealed unique epoxide- and cyclopropanol-containing polyketides named toblerols. Relative and absolute stereochemistry were determined by NMR experiments, chemical derivatization, and the comparison of CD data between the derivatized natural product and a synthesized model compound. Biosynthetic data suggest that the cyclopropanol moiety is generated by carbon-carbon shortening of a more extended precursor. Surprisingly, a knock-out strain impaired in polyketide production showed strong inhibitory activity against other methylobacteria in contrast to the wild-type producer. The activity was inhibited by complementation with toblerols, thus suggesting that these compounds modulate an as-yet unknown methylobacterial antibiotic. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Formation and organization of protein domains in the immunological synapse

NASA Astrophysics Data System (ADS)

Carlson, Andreas; Mahadevan, L.

2014-11-01

The cellular basis for the adaptive immune response during antigen recognition relies on a specialized protein interface known as the immunological synapse. Here, we propose a minimal mathematical model for the dynamics of the IS that encompass membrane mechanics, hydrodynamics and protein kinetics. Simple scaling laws describe the dynamics of protein clusters as a function of membrane stiffness, rigidity of the adhesive proteins, and fluid flow in the synaptic cleft. Numerical simulations complement the scaling laws by quantifying the nucleation, growth and stabilization of proteins domains on the size of the cell. Direct comparison with experiment suggests that passive dynamics suffices to describe the short-time formation and organization of protein clusters, while the stabilization and long time dynamics of the synapse is likely determined by active cytoskeleton processes triggered by receptor binding. Our study reveals that the fluid flow generated by the interplay between membrane deformation and protein binding kinetics can assist immune cells in regulating protein sorting.

Identification of Genetic Bases of Vibrio fluvialis Species-Specific Biochemical Pathways and Potential Virulence Factors by Comparative Genomic Analysis

PubMed Central

Lu, Xin; Liang, Weili; Wang, Yunduan; Xu, Jialiang

2014-01-01

Vibrio fluvialis is an important food-borne pathogen that causes diarrheal illness and sometimes extraintestinal infections in humans. In this study, we sequenced the genome of a clinical V. fluvialis strain and determined its phylogenetic relationships with other Vibrio species by comparative genomic analysis. We found that the closest relationship was between V. fluvialis and V. furnissii, followed by those with V. cholerae and V. mimicus. Moreover, based on genome comparisons and gene complementation experiments, we revealed genetic mechanisms of the biochemical tests that differentiate V. fluvialis from closely related species. Importantly, we identified a variety of genes encoding potential virulence factors, including multiple hemolysins, transcriptional regulators, and environmental survival and adaptation apparatuses, and the type VI secretion system, which is indicative of complex regulatory pathways modulating pathogenesis in this organism. The availability of V. fluvialis genome sequences may promote our understanding of pathogenic mechanisms for this emerging pathogen. PMID:24441165

A Tamper-Resistant and Portable Healthcare Folder

PubMed Central

Anciaux, Nicolas; Berthelot, Morgane; Braconnier, Laurent; Bouganim, Luc; De la Blache, Martine; Gardarin, Georges; Kesmarszky, Philippe; Lartigue, Sophie; Navarre, Jean-François; Pucheral, Philippe; Vandewalle, Jean-Jacques; Zeitouni, Karine

2008-01-01

Electronic health record (EHR) projects have been launched in most developed countries to increase the quality of healthcare while decreasing its cost. The benefits provided by centralizing the healthcare information in database systems are unquestionable in terms of information quality, availability, and protection against failure. Yet, patients are reluctant to give to a distant server the control over highly sensitive data (e.g., data revealing a severe or shameful disease). This paper capitalizes on a new hardware portable device, associating the security of a smart card to the storage capacity of a USB key, to give back to the patient the control over his medical data. This paper shows how this device can complement a traditional EHR server to (1) protect and share highly sensitive data among trusted parties and (2) provide a seamless access to the data even in disconnected mode. The proposed architecture is experimented in the context of a medicosocial network providing medical care and social services at home for elderly people. PMID:18615200

What Drives the Variability of the Atlantic Water Circulation in the Arctic Ocean?

NASA Astrophysics Data System (ADS)

Lique, C.; Johnson, H. L.

2016-02-01

The Atlantic Water (AW) layer in the Arctic Basin is isolated from the atmosphere by the overlaying surface layer; yet observations of the AW pan-Arctic boundary current have revealed that the velocities in this layer exhibit significant variations on all timescales. Here, analysis of a global ocean/sea ice model hindcast, complemented by experiments performed with an idealized process model, are used to investigate what controls the variability of AW circulation, with a focus on the role of wind forcing. The AW circulation carries the imprint of wind variations, both remotely over the Nordic and Barents seas where they force variability on the AW inflow to the Arctic Basin, and locally over the Arctic Basin through the forcing of the wind-driven Beaufort gyre, which modulates and transfers the wind variability to the AW layer. Our results further suggest that understanding variability in the large amount of heat contained within the AW layer requires a better understanding of the circulation within both AW and surface layers.

A major protein component of the Bacillus subtilis biofilm matrix.

PubMed

Branda, Steven S; Chu, Frances; Kearns, Daniel B; Losick, Richard; Kolter, Roberto

2006-02-01

Microbes construct structurally complex multicellular communities (biofilms) through production of an extracellular matrix. Here we present evidence from scanning electron microscopy showing that a wild strain of the Gram positive bacterium Bacillus subtilis builds such a matrix. Genetic, biochemical and cytological evidence indicates that the matrix is composed predominantly of a protein component, TasA, and an exopolysaccharide component. The absence of TasA or the exopolysaccharide resulted in a residual matrix, while the absence of both components led to complete failure to form complex multicellular communities. Extracellular complementation experiments revealed that a functional matrix can be assembled even when TasA and the exopolysaccharide are produced by different cells, reinforcing the view that the components contribute to matrix formation in an extracellular manner. Having defined the major components of the biofilm matrix and the control of their synthesis by the global regulator SinR, we present a working model for how B. subtilis switches between nomadic and sedentary lifestyles.

Co(II) Coordination in Prokaryotic Zinc Finger Domains as Revealed by UV-Vis Spectroscopy.

PubMed

Sivo, Valeria; D'Abrosca, Gianluca; Russo, Luigi; Iacovino, Rosa; Pedone, Paolo Vincenzo; Fattorusso, Roberto; Isernia, Carla; Malgieri, Gaetano

2017-01-01

Co(II) electronic configuration allows its use as a spectroscopic probe in UV-Vis experiments to characterize the metal coordination sphere that is an essential component of the functional structure of zinc-binding proteins and to evaluate the metal ion affinities of these proteins. Here, exploiting the capability of the prokaryotic zinc finger to use different combinations of residues to properly coordinate the structural metal ion, we provide the UV-Vis characterization of Co(II) addition to Ros87 and its mutant Ros87_C27D which bears an unusual CysAspHis 2 coordination sphere. Zinc finger sites containing only one cysteine have been infrequently characterized. We show for the CysAspHis 2 coordination an intense d - d transition band, blue-shifted with respect to the Cys 2 His 2 sphere. These data complemented by NMR and CD data demonstrate that the tetrahedral geometry of the metal site is retained also in the case of a single-cysteine coordination sphere.

The long non-coding RNA GAS5 differentially regulates cell cycle arrest and apoptosis through activation of BRCA1 and p53 in human neuroblastoma

PubMed Central

Mazar, Joseph; Rosado, Amy; Shelley, John; Marchica, John; Westmoreland, Tamarah J

2017-01-01

The long non-coding RNA GAS5 has been shown to modulate cancer proliferation in numerous human cancer systems and has been correlated with successful patient outcome. Our examination of GAS5 in neuroblastoma has revealed robust expression in both MYCN-amplified and non-amplified cell lines. Knockdown of GAS5 In vitro resulted in defects in cell proliferation, apoptosis, and induced cell cycle arrest. Further analysis of GAS5 clones revealed multiple novel splice variants, two of which inversely modulated with MYCN status. Complementation studies of the variants post-knockdown of GAS5 indicated alternate phenotypes, with one variant (FL) considerably enhancing cell proliferation by rescuing cell cycle arrest and the other (C2) driving apoptosis, suggesting a unique role for each in neuroblastoma cancer physiology. Global sequencing and ELISA arrays revealed that the loss of GAS5 induced p53, BRCA1, and GADD45A, which appeared to modulate cell cycle arrest in concert. Complementation with only the FL GAS5 clone could rescue cell cycle arrest, stabilizing HDM2, and leading to the loss of p53. Together, these data offer novel therapeutic targets in the form of lncRNA splice variants for separate challenges against cancer growth and cell death. PMID:28035057

[The transgenerational transmission of traumatic experiences of the Second World War over three generations--a psychoanalytical perspective].

PubMed

Silke, Wiegand-Grefe; Möller, Birgit

2012-01-01

The paper presents some reflections on the transgenerational transmission of traumatic experiences of war and in particular bombing during Second World War. These theoretical considerations are based on a case study (family interview) deriving from the research project "Kriegskindheit im Hamburger Feuersturm" additionally illustrated and complemented with impressions based on interviews with three generations in context of the project.

Microgravity

NASA Image and Video Library

1995-10-20

Payload specialist Fred Leslie makes use of the versatile U.S. Microgravity Laboratory (USML-2) glovebox to conduct an investigation with the Oscillatory Thermocapillary Flow Experiment (OTFE). This complement of the Surface-Tension-Driven Convection Experiment (STDCE) studies the shapes that fluid surfaces in weightless environments assume within specific containers. Leslie was one of two guest researchers who joined five NASA astronauts for 16 days of on Earth-orbit research in support of USML-2.

Intronic sequences are required for AINTEGUMENTA-LIKE6 expression in Arabidopsis flowers.

PubMed

Krizek, Beth A

2015-10-12

The AINTEGUMENTA-LIKE6/PLETHORA3 (AIL6/PLT3) gene of Arabidopsis thaliana is a key regulator of growth and patterning in both shoots and roots. AIL6 encodes an AINTEGUMENTA-LIKE/PLETHORA (AIL/PLT) transcription factor that is expressed in the root stem cell niche, the peripheral region of the shoot apical meristem and young lateral organ primordia. In flowers, AIL6 acts redundantly with AINTEGUMENTA (ANT) to regulate floral organ positioning, growth, identity and patterning. Experiments were undertaken to define the genomic regions required for AIL6 function and expression in flowers. Transgenic plants expressing a copy of the coding region of AIL6 in the context of 7.7 kb of 5' sequence and 919 bp of 3' sequence (AIL6:cAIL6-3') fail to fully complement AIL6 function when assayed in the ant-4 ail6-2 double mutant background. In contrast, a genomic copy of AIL6 with the same amount of 5' and 3' sequence (AIL6:gAIL6-3') can fully complement ant-4 ail6-2. In addition, a genomic copy of AIL6 with 590 bp of 5' sequence and 919 bp of 3' sequence (AIL6m:gAIL6-3') complements ant-4 ail6-2 and contains all regulatory elements needed to confer normal AIL6 expression in inflorescences. Efforts to map cis-regulatory elements reveal that the third intron of AIL6 contains enhancer elements that confer expression in young flowers but in a broader pattern than that of AIL6 mRNA in wild-type flowers. Some AIL6:gAIL6-3' and AIL6m:gAIL6-3' lines confer an over-rescue phenotype in the ant-4 ail6-2 background that is correlated with higher levels of AIL6 mRNA accumulation. The results presented here indicate that AIL6 intronic sequences serve as transcriptional enhancer elements. In addition, the results show that increased expression of AIL6 can partially compensate for loss of ANT function in flowers.

Proteomic analysis in peritoneal dialysis patients with different peritoneal transport characteristics.

PubMed

Wen, Qiong; Zhang, Li; Mao, Hai-Ping; Tang, Xue-Qing; Rong, Rong; Fan, Jin-Jin; Yu, Xue-Qing

2013-08-30

Peritoneal membranes can be categorized as high, high average, low average, and low transporters, based on the removal or transport rate of solutes. In this study, we used proteomic analysis to determine the differences in proteins removed by different types of peritoneal membranes. Peritoneal transport characteristics in patients who received peritoneal dialysis therapy were assessed by a peritoneal equilibration test. Two-dimensional differential gel electrophoresis technology followed by quantitative analysis was performed to study the variation in protein expression from peritoneal dialysis effluents (PDE) among different groups. Proteins were identified by MALDI-TOF-MS/MS analyses. Further validation in PDE or serum was performed utilizing ELISA analysis. Proteomics analysis revealed ten protein spots with significant differences in intensity levels among different groups, including vitamin D-binding protein, complement C3, apolipoprotein-A1, complement factor C4A, haptoglobin, alpha-1 antitrypsin, immunoglobulin kappa light chain, alpha-2-microglobulin, retinol-binding protein 4 and transthyretin. The levels of vitamin D-binding protein, complement C3, and apolipoprotein-A1 in PDE derived from different groups were greatly varied (P<0.05). However, no significant difference was found in the serum levels of these proteins among different groups (P>0.05 for all groups). This study provides a novel overview of the differences in PDE proteomes of four types of peritoneal membranes. Vitamin D-binding protein, complement C3, and apolipoprotein-A1 showed enhanced expression in PDE of patients with high transporter. Copyright © 2013 Elsevier Inc. All rights reserved.

Exploiting a novel conformational switch to control innate immunity mediated by complement protein C3a.

PubMed

Lohman, Rink-Jan; Hamidon, Johan K; Reid, Robert C; Rowley, Jessica A; Yau, Mei-Kwan; Halili, Maria A; Nielsen, Daniel S; Lim, Junxian; Wu, Kai-Chen; Loh, Zhixuan; Do, Anh; Suen, Jacky Y; Iyer, Abishek; Fairlie, David P

2017-08-24

Complement C3a is an important protein in innate and adaptive immunity, but its specific roles in vivo remain uncertain because C3a degrades rapidly to form the C3a-desArg protein, which does not bind to the C3a receptor and is indistinguishable from C3a using antibodies. Here we develop the most potent, stable and highly selective small molecule modulators of C3a receptor, using a heterocyclic hinge to switch between agonist and antagonist ligand conformations. This enables characterization of C3 areceptor-selective pro- vs. anti-inflammatory actions in human mast cells and macrophages, and in rats. A C3a receptor-selective agonist induces acute rat paw inflammation by first degranulating mast cells before activating macrophages and neutrophils. An orally administered C3a receptor-selective antagonist inhibits mast cell degranulation, thereby blocking recruitment and activation of macrophages and neutrophils, expression of inflammatory mediators and inflammation in a rat paw edema model. These novel tools reveal the mechanism of C3a-induced inflammation and provide new insights to complement-based medicines.Complement C3a is an important protein in innate and adaptive immunity, but its roles in vivo are unclear. Here the authors develop novel chemical agonists and antagonists for the C3a receptor, and show that they modulate mast cell degranulation and inflammation in a rat paw edema model.

The SaeRS Two-Component System Controls Survival of Staphylococcus aureus in Human Blood through Regulation of Coagulase

PubMed Central

Guo, Haiyong; Hall, Jeffrey W.; Yang, Junshu; Ji, Yinduo

2017-01-01

The SaeRS two-component system plays important roles in regulation of key virulence factors and pathogenicity. In this study, however, we found that the deletion mutation of saeRS enhanced bacterial survival in human blood, whereas complementation of the mutant with SaeRS returned survival to wild-type levels. Moreover, these phenomena were observed in different MRSA genetic background isolates, including HA-MRSA WCUH29, CA-MRSA 923, and MW2. To elucidate which gene(s) regulated by SaeRS contribute to the effect, we conducted a series of complementation studies with selected known SaeRS target genes in trans. We found coagulase complementation abolished the enhanced survival of the SaeRS mutant in human blood. The coa and saeRS deletion mutants exhibited a similar survival phenotype in blood. Intriguingly, heterologous expression of coagulase decreased survival of S. epidermidis in human blood. Further, the addition of recombinant coagulase to blood significantly decreased the survival of S. aureus. Further, analysis revealed staphylococcal resistance to killing by hydrogen peroxide was partially dependent on the presence or absence of coagulase. Furthermore, complementation with coagulase, but not SaeRS, returned saeRS/coa double mutant survival in blood to wild-type levels. These data indicate SaeRS modulates bacterial survival in blood in coagulase-dependent manner. Our results provide new insights into the role of staphylococcal SaeRS and coagulase on bacterial survival in human blood. PMID:28611950

Loxoprofen sodium induces the production of complement C5a in human serum.

PubMed

Kumagai, Tomoaki; Yamaguchi, Nozomi; Hirai, Hiroyuki; Kojima, Shigeyuki; Kodani, Yoshiko; Hashiguchi, Akihiko; Haida, Michiko; Nakamura, Masataka

2016-04-01

Basophil activation test (BAT) is an in vitro allergy test that is useful to identify allergens that cause IgE-dependent allergies. The test has been used to detect not only food allergies and allergies caused by environmental factors but also to detect drug hypersensitivity, which has been known to include IgE-independent reactions. In our preliminary studies in which BAT was applied to detect hypersensitivity of loxoprofen, a non-steroidal anti-inflammatory drug (NSAID), conventional BAT with incubation for 30min did not show basophil activation by means of increased CD203c expression. In this study, we extended the incubation time to 24h on the basis of the hypothesis that loxoprofen indirectly activates basophils. Basophils from healthy control donors as well as allergic patients showed up-regulation of CD203c after incubation with loxoprofen for 24h. Activation was induced using loxoprofen-treated serum. Proteomic and pharmacologic analyses revealed that serum incubation with loxoprofen generated an active complement component C5a, which induced CD203c expression via binding to the C5a receptor on basophils. Because C3a production was also detected after incubation for 24h, loxoprofen is likely to stimulate the complement classical pathway. Our findings suggest that the complement activation is involved in drug hypersensitivity and the suppression of this activation may contribute to the elimination of false positive of BAT for drug allergies. Copyright © 2016 Elsevier B.V. All rights reserved.

X and Y Chromosome Complement Influence Adiposity and Metabolism in Mice

PubMed Central

Chen, Xuqi; McClusky, Rebecca; Itoh, Yuichiro; Reue, Karen

2013-01-01

Three different models of MF1 strain mice were studied to measure the effects of gonadal secretions and sex chromosome type and number on body weight and composition, and on related metabolic variables such as glucose homeostasis, feeding, and activity. The 3 genetic models varied sex chromosome complement in different ways, as follows: 1) “four core genotypes” mice, comprising XX and XY gonadal males, and XX and XY gonadal females; 2) the XY* model comprising groups similar to XO, XX, XY, and XXY; and 3) a novel model comprising 6 groups having XO, XX, and XY chromosomes with either testes or ovaries. In gonadally intact mice, gonadal males were heavier than gonadal females, but sex chromosome complement also influenced weight. The male/female difference was abolished by adult gonadectomy, after which mice with 2 sex chromosomes (XX or XY) had greater body weight and percentage of body fat than mice with 1 X chromosome. A second sex chromosome of either type, X or Y, had similar effects, indicating that the 2 sex chromosomes each possess factors that influence body weight and composition in the MF1 genetic background. Sex chromosome complement also influenced metabolic variables such as food intake and glucose tolerance. The results reveal a role for the Y chromosome in metabolism independent of testes and gonadal hormones and point to a small number of X–Y gene pairs with similar coding sequences as candidates for causing these effects. PMID:23397033

Verdi Invades the Kindergarten.

ERIC Educational Resources Information Center

McGirr, Paula Ifft

1995-01-01

Children can complement all areas of their language learning with music, and can enhance their musical activities with language. Opportunities to experience sounds, language, and rhythmic movement support the learning and development of the whole child. Activities dealing with children's books that have musical themes, song picture books, and…

Story Immersion of Videogames for Youth Health Promotion: A Review of Literature

PubMed Central

Baranowski, Tom; Thompson, Debbe; Buday, Richard

2012-01-01

Abstract This article reviews research in the fields of psychology, literature, communication, human–computer interaction, public health, and consumer behavior on narrative and its potential relationships with videogames and story immersion. It also reviews a narrative's role in complementing behavioral change theories and the potential of story immersion for health promotion through videogames. Videogames have potential for health promotion and may be especially promising when attempting to reach youth. An understudied characteristic of videogames is that many contain a narrative, or story. Story immersion (transportation) is a mechanism through which a narrative influences players' cognition, affect, and, potentially, health behavior. Immersion promotes the suspension of disbelief and the reduction of counterarguments, enables the story experience as a personal experience, and creates the player's deep affection for narrative protagonists. Story immersion complements behavioral change theories, including the Theory of Planned Behavior, Social Cognitive Theory, and Self-Determination Theory. Systematic investigations are needed to realize the powerful potential of interactive narratives within theory-driven research. PMID:24416639

Story Immersion of Videogames for Youth Health Promotion: A Review of Literature.

PubMed

Lu, Amy Shirong; Baranowski, Tom; Thompson, Debbe; Buday, Richard

2012-06-01

This article reviews research in the fields of psychology, literature, communication, human-computer interaction, public health, and consumer behavior on narrative and its potential relationships with videogames and story immersion. It also reviews a narrative's role in complementing behavioral change theories and the potential of story immersion for health promotion through videogames. Videogames have potential for health promotion and may be especially promising when attempting to reach youth. An understudied characteristic of videogames is that many contain a narrative, or story. Story immersion (transportation) is a mechanism through which a narrative influences players' cognition, affect, and, potentially, health behavior. Immersion promotes the suspension of disbelief and the reduction of counterarguments, enables the story experience as a personal experience, and creates the player's deep affection for narrative protagonists. Story immersion complements behavioral change theories, including the Theory of Planned Behavior, Social Cognitive Theory, and Self-Determination Theory. Systematic investigations are needed to realize the powerful potential of interactive narratives within theory-driven research.

STS-64 SAFER Assembly

NASA Image and Video Library

1993-12-10

S93-50137 (December 1993) --- This small mobility-aiding back harness, complemented in extravehicular activity (EVA) with a hand controller unit and called the Simplified Aid for EVA Rescue (SAFER) system, will get extensive in-space evaluation and testing during the STS-64 mission. In this view the SAFER is open to reveal the gas supply and thrusters. SAFER is to fly on STS-76 as well.

Inability to empathize: brain lesions that disrupt sharing and understanding another’s emotions

PubMed Central

2014-01-01

Emotional empathy—the ability to recognize, share in, and make inferences about another person’s emotional state—is critical for all social interactions. The neural mechanisms underlying emotional empathy have been widely studied with functional imaging of healthy participants. However, functional imaging studies reveal correlations between areas of activation and performance of a task, so that they can only reveal areas engaged in a task, rather than areas of the brain that are critical for the task. Lesion studies complement functional imaging, to identify areas necessary for a task. Impairments in emotional empathy have been mostly studied in neurological diseases with fairly diffuse injury, such as traumatic brain injury, autism and dementia. The classic ‘focal lesion’ is stroke. There have been scattered studies of patients with impaired empathy after stroke and other focal injury, but these studies have included small numbers of patients. This review will bring together data from these studies, to complement evidence from functional imaging. Here I review how focal lesions affect emotional empathy. I will show how lesion studies contribute to the understanding of the cognitive and neural mechanisms underlying emotional empathy, and how they contribute to the management of patients with impaired emotional empathy. PMID:24293265

Biostack 3 experiment MA-107

NASA Technical Reports Server (NTRS)

Buecker, H.; Facius, R.; Hildebrand, D.; Horneck, G.; Reitz, G.; Scheidemann, U.; Schaefer, M.; Thomas, C.; Toth, B.; Kranz, A. R.

1976-01-01

The Biostack III experiment onboard the Apollo spacecraft during the Apollo Soyuz Test Project complemented the Biostack I and II experiments of the Apollo 16 and 17 missions. The objectives of these experiments were to study the biological effects of individual heavy cosmic particles of high energy loss (HZE) not available on earth, to study the influence of additional space flight factors, to obtain knowledge on the mechanism by which HZE particles damage biological materials, to get information on the spectrum of charge and energy of the cosmic ions in the spacecraft, and to estimate the radiation hazards to man in space.

Atmospheric microphysical experiments on an orbital platform

NASA Technical Reports Server (NTRS)

Eaton, L. R.

1974-01-01

The Zero-Gravity Atmospheric Cloud Physics Laboratory is a Shuttle/Spacelab payload which will be capable of performing a large range of microphysics experiments. This facility will complement terrestrial cloud physics research by allowing many experiments to be performed which cannot be accomplished within the confines of a terrestrial laboratory. This paper reviews the general Cloud Physics Laboratory concept and the experiment scope. The experimental constraints are given along with details of the proposed equipment. Examples of appropriate experiments range from three-dimensional simulation of the earth and planetary atmosphere and of ocean circulation to cloud electrification processes and the effects of atmospheric pollution materials on microphysical processes.

The major autoantibody epitope on factor H in atypical hemolytic uremic syndrome is structurally different from its homologous site in factor H-related protein 1, supporting a novel model for induction of autoimmunity in this disease.

PubMed

Bhattacharjee, Arnab; Reuter, Stefanie; Trojnár, Eszter; Kolodziejczyk, Robert; Seeberger, Harald; Hyvärinen, Satu; Uzonyi, Barbara; Szilágyi, Ágnes; Prohászka, Zoltán; Goldman, Adrian; Józsi, Mihály; Jokiranta, T Sakari

2015-04-10

Atypical hemolytic uremic syndrome (aHUS) is characterized by complement attack against host cells due to mutations in complement proteins or autoantibodies against complement factor H (CFH). It is unknown why nearly all patients with autoimmune aHUS lack CFHR1 (CFH-related protein-1). These patients have autoantibodies against CFH domains 19 and 20 (CFH19-20), which are nearly identical to CFHR1 domains 4 and 5 (CFHR14-5). Here, binding site mapping of autoantibodies from 17 patients using mutant CFH19-20 constructs revealed an autoantibody epitope cluster within a loop on domain 20, next to the two buried residues that are different in CFH19-20 and CFHR14-5. The crystal structure of CFHR14-5 revealed a difference in conformation of the autoantigenic loop in the C-terminal domains of CFH and CFHR1, explaining the variation in binding of autoantibodies from some aHUS patients to CFH19-20 and CFHR14-5. The autoantigenic loop on CFH seems to be generally flexible, as its conformation in previously published structures of CFH19-20 bound to the microbial protein OspE and a sialic acid glycan is somewhat altered. Cumulatively, our data suggest that association of CFHR1 deficiency with autoimmune aHUS could be due to the structural difference between CFHR1 and the autoantigenic CFH epitope, suggesting a novel explanation for CFHR1 deficiency in the pathogenesis of autoimmune aHUS. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

A novel L-ficolin/mannose-binding lectin chimeric molecule with enhanced activity against Ebola virus.

PubMed

Michelow, Ian C; Dong, Mingdong; Mungall, Bruce A; Yantosca, L Michael; Lear, Calli; Ji, Xin; Karpel, Marshall; Rootes, Christina L; Brudner, Matthew; Houen, Gunnar; Eisen, Damon P; Kinane, T Bernard; Takahashi, Kazue; Stahl, Gregory L; Olinger, Gene G; Spear, Gregory T; Ezekowitz, R Alan B; Schmidt, Emmett V

2010-08-06

Ebola viruses constitute a newly emerging public threat because they cause rapidly fatal hemorrhagic fevers for which no treatment exists, and they can be manipulated as bioweapons. We targeted conserved N-glycosylated carbohydrate ligands on viral envelope surfaces using novel immune therapies. Mannose-binding lectin (MBL) and L-ficolin (L-FCN) were selected because they function as opsonins and activate complement. Given that MBL has a complex quaternary structure unsuitable for large scale cost-effective production, we sought to develop a less complex chimeric fusion protein with similar ligand recognition and enhanced effector functions. We tested recombinant human MBL and three L-FCN/MBL variants that contained the MBL carbohydrate recognition domain and varying lengths of the L-FCN collagenous domain. Non-reduced chimeric proteins formed predominantly nona- and dodecameric oligomers, whereas recombinant human MBL formed octadecameric and larger oligomers. Surface plasmon resonance revealed that L-FCN/MBL76 had the highest binding affinities for N-acetylglucosamine-bovine serum albumin and mannan. The same chimeric protein displayed superior complement C4 cleavage and binding to calreticulin (cC1qR), a putative receptor for MBL. L-FCN/MBL76 reduced infection by wild type Ebola virus Zaire significantly greater than the other molecules. Tapping mode atomic force microscopy revealed that L-FCN/MBL76 was significantly less tall than the other molecules despite similar polypeptide lengths. We propose that alterations in the quaternary structure of L-FCN/MBL76 resulted in greater flexibility in the collagenous or neck region. Similarly, a more pliable molecule might enhance cooperativity between the carbohydrate recognition domains and their cognate ligands, complement activation, and calreticulin binding dynamics. L-FCN/MBL chimeric proteins should be considered as potential novel therapeutics.

Heterologous Complementation Reveals a Specialized Activity for BacA in the Medicago-Sinorhizobium meliloti Symbiosis.

PubMed

diCenzo, George C; Zamani, Maryam; Ludwig, Hannah N; Finan, Turlough M

2017-04-01

The bacterium Sinorhizobium meliloti Rm2011 forms N 2 -fixing root nodules on alfalfa and other leguminous plants. The pSymB chromid contains a 110-kb region (the ETR region) showing high synteny to a chromosomally located region in Sinorhizobium fredii NGR234 and related rhizobia. We recently introduced the ETR region from S. fredii NGR234 into the S. meliloti chromosome. Here, we report that, unexpectedly, the S. fredii NGR234 ETR region did not complement deletion of the S. meliloti ETR region in symbiosis with Medicago sativa. This phenotype was due to the bacA gene of NGR234 not being functionally interchangeable with the S. meliloti bacA gene during M. sativa symbiosis. Further analysis revealed that, whereas bacA genes from S. fredii or Rhizobium leguminosarum bv. viciae 3841 failed to complement the Fix - phenotype of a S. meliloti bacA mutant with M. sativa, they allowed for further developmental progression prior to a loss of viability. In contrast, with Melilotus alba, bacA from S. fredii and R. leguminosarum supported N 2 fixation by a S. meliloti bacA mutant. Additionally, the S. meliloti bacA gene can support N 2 fixation of a R. leguminosarum bacA mutant during symbiosis with Pisum sativum. A phylogeny of BacA proteins illustrated that S. meliloti BacA has rapidly diverged from most rhizobia and has converged toward the sequence of pathogenic genera Brucella and Escherichia. These data suggest that the S. meliloti BacA has evolved toward a specific interaction with Medicago and highlights the limitations of using a single model system for the study of complex biological topics.

Herpes Simplex Virus 1 UL37 Protein Tyrosine Residues Conserved among All Alphaherpesviruses Are Required for Interactions with Glycoprotein K, Cytoplasmic Virion Envelopment, and Infectious Virus Production

PubMed Central

Chouljenko, Dmitry V.; Jambunathan, Nithya; Chouljenko, Vladimir N.; Naderi, Misagh; Brylinski, Michal; Caskey, John R.

2016-01-01

ABSTRACT The herpes simplex virus 1 (HSV-1) UL37 protein functions in virion envelopment at trans-Golgi membranes, as well as in retrograde and anterograde transport of virion capsids. Recently, we reported that UL37 interacts with glycoprotein K (gK) and its interacting partner protein UL20 (N. Jambunathan, D. Chouljenko, P. Desai, A. S. Charles, R. Subramanian, V. N. Chouljenko, and K. G. Kousoulas, J Virol 88:5927–5935, 2014, http://dx.doi.org/10.1128/JVI.00278-14), facilitating cytoplasmic virion envelopment. Alignment of UL37 homologs encoded by alphaherpesviruses revealed the presence of highly conserved residues in the central portion of the UL37 protein. A cadre of nine UL37 site-specific mutations were produced and tested for their ability to inhibit virion envelopment and infectious virus production. Complementation analysis revealed that replacement of tyrosines 474 and 480 with alanine failed to complement the UL37-null virus, while all other mutated UL37 genes complemented the virus efficiently. The recombinant virus DC474-480 constructed with tyrosines 474, 476, 477, and 480 mutated to alanine residues produced a gK-null-like phenotype characterized by the production of very small plaques and accumulation of capsids in the cytoplasm of infected cells. Recombinant viruses having either tyrosine 476 or 477 replaced with alanine produced a wild-type phenotype. Immunoprecipitation assays revealed that replacement of all four tyrosines with alanines substantially reduced the ability of gK to interact with UL37. Alignment of HSV UL37 with the human cytomegalovirus and Epstein-Barr virus UL37 homologs revealed that Y480 was conserved only for alphaherpesviruses. Collectively, these results suggest that the UL37 conserved tyrosine 480 residue plays a crucial role in interactions with gK to facilitate cytoplasmic virion envelopment and infectious virus production. IMPORTANCE The HSV-1 UL37 protein is conserved among all herpesviruses, functions in both retrograde and anterograde transport of virion capsids, and plays critical roles in cytoplasmic virion envelopment by interacting with gK. We show here that UL37 tyrosine residues conserved among all alphaherpesviruses serve critical roles in cytoplasmic virion envelopment and interactions with gK. PMID:27630233

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pilgrim, Corey D.; Zavarin, Mavrik; Casey, William H.

Here, the rates of ligand exchange into the geochemically important [NpO 2(CO 3) 3] 4– aqueous complex are measured as a function of pressure in order to complement existing data on the isostructural [UO 2(CO 3) 3] 4– complex. Experiments are conducted at pH conditions where the rate of exchange is independent of the proton concentration. Unexpectedly, the experiments show a distinct difference in the pressure dependencies of rates of exchange for the uranyl and neptunyl complexes.

Neutral Pion Photoproduction on Neutron

DOE PAGES

Bulychev, S. A.; Kudryavtsev, A. E.; Kulikov, V. V.; ...

2018-03-12

The reaction γn → π 0n is investigated both theoretically and experimentally as an important step toward determining the electromagnetic coupling constants of the N* and Δ* resonances. We analyze the data on the collisions of γ quanta with energies between 200 and 800 MeV with a deuterium target collected by the A2 experiment in Mainz, Germany. Furthermore, these complement the data for neutral-pion photoproduction on protons obtained by the same experiment.

Guidelines for Interpretive Building Design.

ERIC Educational Resources Information Center

Manly, Richard J., Ed.

This booklet is intended to assist those planning nature centers to choose building designs appropriate for intended purposes. The publication presents a set of general interpretive building-site and design considerations compiled over years of experience in nature center design. These generalizations are complemented by examples of floor plans,…

The Thinking Styles of Human Resource Practitioners

ERIC Educational Resources Information Center

Higgins, Paul; Zhang, Li-fang

2009-01-01

Purpose: Drawing upon Sternberg's theory of mental self-government, this paper aims to investigate the thinking styles and workplace experiences of 152 human resource (HR) practitioners pursuing Chartered Institute of Personnel and Development (CIPD) membership. It seeks to explore whether their thinking styles complemented their jobs and consider…

Towards Memory-Aware Services and Browsing through Lifelogging Sensing

PubMed Central

Arcega, Lorena; Font, Jaime; Cetina, Carlos

2013-01-01

Every day we receive lots of information through our senses that is lost forever, because it lacked the strength or the repetition needed to generate a lasting memory. Combining the emerging Internet of Things and lifelogging sensors, we believe it is possible to build up a Digital Memory (Dig-Mem) in order to complement the fallible memory of people. This work shows how to realize the Dig-Mem in terms of interactions, affinities, activities, goals and protocols. We also complement this Dig-Mem with memory-aware services and a Dig-Mem browser. Furthermore, we propose a RFID Tag-Sharing technique to speed up the adoption of Dig-Mem. Experimentation reveals an improvement of the user understanding of Dig-Mem as time passes, compared to natural memories where the level of detail decreases over time. PMID:24196436

UV damage-specific DNA-binding protein in xeroderma pigmentosum complementation group E

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kataoka, H.; Fujiwara, Y.

1991-03-29

The gel mobility shift assay method revealed a specifically ultraviolet (UV) damage recognizing, DNA-binding protein in nuclear extracts of normal human cells. The resulted DNA/protein complexes caused the two retarded mobility shifts. Four xeroderma pigmentosum complementation group E (XPE) fibroblast strains derived from unrelated Japanese families were not deficient in such a DNA damage recognition/binding protein because of the normal complex formation and gel mobility shifts, although we confirmed the reported lack of the protein in the European XPE (XP2RO and XP3RO) cells. Thus, the absence of this binding protein is not always commonly observed in all the XPE strains,more » and the partially repair-deficient and intermediately UV-hypersensitive phenotype of XPE cells are much similar whether or not they lack the protein.« less

Complementation of Conjugation Functions of Streptomyces lividans Plasmid pIJ101 by the Related Streptomyces Plasmid pSB24.2

PubMed Central

Pettis, Gregg S.; Prakash, Shubha

1999-01-01

A database search revealed extensive sequence similarity between Streptomyces lividans plasmid pIJ101 and Streptomyces plasmid pSB24.2, which is a deletion derivative of Streptomyces cyanogenus plasmid pSB24.1. The high degree of relatedness between the two plasmids allowed the construction of a genetic map of pSB24.2, consisting of putative transfer and replication loci. Two pSB24.2 loci, namely, the cis-acting locus for transfer (clt) and the transfer-associated korB gene, were shown to be capable of complementing the pIJ101 clt and korB functions, respectively, a result that is consistent with the notion that pIJ101 and the parental plasmid pSB24.1 encode highly similar, if not identical, conjugation systems. PMID:10419972

Identification and characterization of an autolysin gene, atlg, from Streptococcus sobrinus.

PubMed

Yamada, Arisa; Tamura, Haruki; Kato, Hirohisa

2009-02-01

AtlA is a major cell-lytic enzyme called autolysin in Streptococcus mutans. In this study, we identified the atlg gene-encoding autolysin (Atlg), consisting of 863 residues from Streptococcus sobrinus 6715DP, and confirmed lytic activity of recombinant Atlg by zymography of S. sobrinus cells. An atlA-inactivated mutant was constructed in S. mutans Xc, and the atlg gene product was characterized by plasmid complementation. Microscopic analysis, saliva-induced aggregation assay and autolysis assay of static cultures in air revealed that the atlg gene product partially complemented the role of AtlA. Furthermore, the capability of biofilm formation of the atlA-deficient mutant cultivated in air was restored by plasmid comprising the atlg gene. These findings suggest that Atlg may be involved in cell separation and biofilm formation in S. sobrinus.

Radiation testing of GaAs on CRRES and LIPS experiment

NASA Technical Reports Server (NTRS)

Trumble, T. M.; Masloski, K.

1984-01-01

The radiation damage of solar cells has become a prime concern to the U.S. Air Force due to longer satellite lifetime requirements. Flight experiments were undertaken on the Navy Living Plume Shield (LPS) satellite and the NASA/Air Force Combined Release and Radiation Effects Satellite (CRRES) to complement existing radiation testing. Each experiment, the rationale behind it, and its approach and status are presented. The effect of space radiation on gallium arsenide (GaAs) solar cells was the central parameter investigated. Specifications of the GaAs solar cells are given.

Pathogenic Variants in Complement Genes and Risk of Atypical Hemolytic Uremic Syndrome Relapse after Eculizumab Discontinuation.

PubMed

Fakhouri, Fadi; Fila, Marc; Provôt, François; Delmas, Yahsou; Barbet, Christelle; Châtelet, Valérie; Rafat, Cédric; Cailliez, Mathilde; Hogan, Julien; Servais, Aude; Karras, Alexandre; Makdassi, Raifah; Louillet, Feriell; Coindre, Jean-Philippe; Rondeau, Eric; Loirat, Chantal; Frémeaux-Bacchi, Véronique

2017-01-06

The complement inhibitor eculizumab has dramatically improved the outcome of atypical hemolytic uremic syndrome. However, the optimal duration of eculizumab treatment in atypical hemolytic uremic syndrome remains debated. We report on the French atypical hemolytic uremic syndrome working group's first 2-year experience with eculizumab discontinuation in patients with atypical hemolytic uremic syndrome. Using the French atypical hemolytic uremic syndrome registry database, we retrospectively identified all dialysis-free patients with atypical hemolytic uremic syndrome who discontinued eculizumab between 2010 and 2014 and reviewed their relevant clinical and biologic data. The decision to discontinue eculizumab was made by the clinician in charge of the patient. All patients were closely monitored by regular urine dipsticks and blood tests. Eculizumab was rapidly (24-48 hours) restarted in case of relapse. Among 108 patients treated with eculizumab, 38 patients (nine children and 29 adults) discontinued eculizumab (median treatment duration of 17.5 months). Twenty-one patients (55%) carried novel or rare complement genes variants. Renal recovery under eculizumab was equally good in patients with and those without complement gene variants detected. After a median follow-up of 22 months, 12 patients (31%) experienced atypical hemolytic uremic syndrome relapse. Eight of 11 patients (72%) with complement factor H variants, four of eight patients (50%) with membrane cofactor protein variants, and zero of 16 patients with no rare variant detected relapsed. In relapsing patients, early reintroduction (≤48 hours) of eculizumab led to rapid (<7 days) hematologic remission and a return of serum creatinine to baseline level in a median time of 26 days. At last follow-up, renal function remained unchanged in nonrelapsing and relapsing patients compared with baseline values before eculizumab discontinuation. Pathogenic variants in complement genes were associated with higher risk of atypical hemolytic uremic syndrome relapse after eculizumab discontinuation. Prospective studies are needed to identify biomarkers predictive of relapse and determine the best strategy of retreatment in relapsing patients. Copyright © 2016 by the American Society of Nephrology.

The Transmembrane Region of Guard Cell SLAC1 Channels Perceives CO2 Signals via an ABA-Independent Pathway in Arabidopsis.

PubMed

Yamamoto, Yoshiko; Negi, Juntaro; Wang, Cun; Isogai, Yasuhiro; Schroeder, Julian I; Iba, Koh

2016-02-01

The guard cell S-type anion channel, SLOW ANION CHANNEL1 (SLAC1), a key component in the control of stomatal movements, is activated in response to CO2 and abscisic acid (ABA). Several amino acids existing in the N-terminal region of SLAC1 are involved in regulating its activity via phosphorylation in the ABA response. However, little is known about sites involved in CO2 signal perception. To dissect sites that are necessary for the stomatal CO2 response, we performed slac1 complementation experiments using transgenic plants expressing truncated SLAC1 proteins. Measurements of gas exchange and stomatal apertures in the truncated transgenic lines in response to CO2 and ABA revealed that sites involved in the stomatal CO2 response exist in the transmembrane region and do not require the SLAC1 N and C termini. CO2 and ABA regulation of S-type anion channel activity in guard cells of the transgenic lines confirmed these results. In vivo site-directed mutagenesis experiments targeted to amino acids within the transmembrane region of SLAC1 raise the possibility that two tyrosine residues exposed on the membrane are involved in the stomatal CO2 response. © 2016 American Society of Plant Biologists. All rights reserved.

Quantum interference in an interfacial superconductor.

PubMed

Goswami, Srijit; Mulazimoglu, Emre; Monteiro, Ana M R V L; Wölbing, Roman; Koelle, Dieter; Kleiner, Reinhold; Blanter, Ya M; Vandersypen, Lieven M K; Caviglia, Andrea D

2016-10-01

The two-dimensional superconductor that forms at the interface between the complex oxides lanthanum aluminate (LAO) and strontium titanate (STO) has several intriguing properties that set it apart from conventional superconductors. Most notably, an electric field can be used to tune its critical temperature (T c ; ref. 7), revealing a dome-shaped phase diagram reminiscent of high-T c superconductors. So far, experiments with oxide interfaces have measured quantities that probe only the magnitude of the superconducting order parameter and are not sensitive to its phase. Here, we perform phase-sensitive measurements by realizing the first superconducting quantum interference devices (SQUIDs) at the LAO/STO interface. Furthermore, we develop a new paradigm for the creation of superconducting circuit elements, where local gates enable the in situ creation and control of Josephson junctions. These gate-defined SQUIDs are unique in that the entire device is made from a single superconductor with purely electrostatic interfaces between the superconducting reservoir and the weak link. We complement our experiments with numerical simulations and show that the low superfluid density of this interfacial superconductor results in a large, gate-controllable kinetic inductance of the SQUID. Our observation of robust quantum interference opens up a new pathway to understanding the nature of superconductivity at oxide interfaces.

A behavioral view on chimpanzee personality: exploration tendency, persistence, boldness, and tool-orientation measured with group experiments.

PubMed

Massen, Jorg J M; Antonides, Alexandra; Arnold, Anne-Marie K; Bionda, Thomas; Koski, Sonja E

2013-09-01

Human and nonhuman animals show personality: temporal and contextual consistency in behavior patterns that vary among individuals. In contrast to most other species, personality of chimpanzees, Pan troglodytes, has mainly been studied with non-behavioral methods. We examined boldness, exploration tendency, persistence and tool-orientation in 29 captive chimpanzees using repeated experiments conducted in an ecologically valid social setting. High temporal repeatability and contextual consistency in all these traits indicated they reflected personality. In addition, Principal Component Analysis revealed two independent syndromes, labeled exploration-persistence and boldness. We found no sex or rank differences in the trait scores, but the scores declined with age. Nonetheless, there was considerable inter-individual variation within age-classes, suggesting that behavior was not merely determined by age but also by dispositional effects. In conclusion, our study complements earlier rating studies and adds new traits to the chimpanzee personality, thereby supporting the existence of multiple personality traits among chimpanzees. We stress the importance of ecologically valid behavioral research to assess multiple personality traits and their association, as it allows inclusion of ape studies in the comparison of personality structures across species studied behaviorally, and furthers our attempts to unravel the causes and consequences of animal personality. © 2013 Wiley Periodicals, Inc.

The Transmembrane Region of Guard Cell SLAC1 Channels Perceives CO2 Signals via an ABA-Independent Pathway in Arabidopsis

PubMed Central

Yamamoto, Yoshiko; Negi, Juntaro; Isogai, Yasuhiro; Schroeder, Julian I.; Iba, Koh

2016-01-01

The guard cell S-type anion channel, SLOW ANION CHANNEL1 (SLAC1), a key component in the control of stomatal movements, is activated in response to CO2 and abscisic acid (ABA). Several amino acids existing in the N-terminal region of SLAC1 are involved in regulating its activity via phosphorylation in the ABA response. However, little is known about sites involved in CO2 signal perception. To dissect sites that are necessary for the stomatal CO2 response, we performed slac1 complementation experiments using transgenic plants expressing truncated SLAC1 proteins. Measurements of gas exchange and stomatal apertures in the truncated transgenic lines in response to CO2 and ABA revealed that sites involved in the stomatal CO2 response exist in the transmembrane region and do not require the SLAC1 N and C termini. CO2 and ABA regulation of S-type anion channel activity in guard cells of the transgenic lines confirmed these results. In vivo site-directed mutagenesis experiments targeted to amino acids within the transmembrane region of SLAC1 raise the possibility that two tyrosine residues exposed on the membrane are involved in the stomatal CO2 response. PMID:26764376

Effects of increasing nitrogen and phosphorus concentrations on phytoplankton community growth and toxicity during Planktothrix blooms in Sandusky Bay, Lake Erie.

PubMed

Davis, Timothy W; Bullerjahn, George S; Tuttle, Taylor; McKay, Robert Michael; Watson, Susan B

2015-06-16

Sandusky Bay experiences annual toxic cyanobacterial blooms dominated by Planktothrix agardhii/suspensa. To further understand the environmental drivers of these events, we evaluated changes in the growth response and toxicity of the Planktothrix-dominated blooms to nutrient amendments with orthophosphate (PO4) and inorganic and organic forms of dissolved nitrogen (N; ammonium (NH4), nitrate (NO3) and urea) over the bloom season (June - October). We complemented these with a metagenomic analysis of the planktonic microbial community. Our results showed that bloom growth and microcystin (MC) concentrations responded more frequently to additions of dissolved N than PO4, and that the dual addition of NH4 + PO4 and Urea + PO4 yielded the highest MC concentrations in 54% of experiments. Metagenomic analysis confirmed that P. agardhii/suspensa was the primary MC producer. The phylogenetic distribution of nifH revealed that both heterocystous cyanobacteria and heterotrophic proteobacteria had the genetic potential for N2 fixation in Sandusky Bay. These results suggest that as best management practices are developed for P reductions in Sandusky Bay, managers must be aware of the negative implications of not managing N loading into this system as N may significantly impact cyanobacterial bloom size and toxicity.

Further Observations on the Effect of C. parvum and Anti-Tumour Globulin on Syngeneically Transplanted Mouse Tumours

PubMed Central

Woodruff, M. F. A.; Inchley, M. P.; Dunbar, Noreen

1972-01-01

The inhibitory effect of an i.v. or i.p. injection of C. parvum on intrastrain transplants of a mammary carcinoma in A/HeJ mice has been confirmed, and it has been shown further that C. parvum inhibits the growth of transplants of sarcomata induced with methylcholanthrene both in this strain (members of which lack the fifth component of complement) and in CBA mice (which are not complement deficient). In experiments with the mammary carcinoma, 2 injections of C. parvum on days + 3 and + 9 were more effective than a single injection on day + 3; injections on days + 3 and + 6, or + 3 and + 12, appeared to be marginally less effective than on days + 3 and + 9, but the difference was not statistically significant. Development of the CBA sarcoma was inhibited to about the same extent if, instead of treating the mouse with C. parvum, the tumour cells were pre-incubated with anti-tumour globulin (ATG) in the absence of complement prior to inoculation, and the effect of combining these procedures was much greater than that of either alone. Pre-incubation with ATG had a similar but less marked effect on the development of the mammary carcinoma but had no effect on the A/HeJ sarcoma. Injection (i.v.) of ATG did not inhibit the growth of any of the tumours in these experiments and possible reasons for this are discussed. PMID:5038327

Teasing apart coercion and surprisal: Evidence from eye-movements and ERPs.

PubMed

Delogu, Francesca; Crocker, Matthew W; Drenhaus, Heiner

2017-04-01

Previous behavioral and electrophysiological studies have presented evidence suggesting that coercion expressions (e.g., began the book) are more difficult to process than control expressions like read the book. While this processing cost has been attributed to a specific coercion operation for recovering an event-sense of the complement (e.g., began reading the book), an alternative view based on the Surprisal Theory of language processing would attribute the cost to the relative unpredictability of the complement noun in the coercion compared to the control condition, with no need to postulate coercion-specific mechanisms. In two experiments, monitoring eye-tracking and event-related potentials (ERPs), respectively, we sought to determine whether there is any evidence for coercion-specific processing cost above-and-beyond the difficulty predicted by surprisal, by contrasting coercing and control expressions with a further control condition in which the predictability of the complement noun was similar to that in the coercion condition (e.g., bought the book). While the eye-tracking study showed significant effects of surprisal and a marginal effect of coercion on late reading measures, the ERP study clearly supported the surprisal account. Overall, our findings suggest that the coercion cost largely reflects the surprisal of the complement noun with coercion specific operations possibly influencing later processing stages. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Bimolecular fluorescence complementation: visualization of molecular interactions in living cells.

PubMed

Kerppola, Tom K

2008-01-01

A variety of experimental methods have been developed for the analysis of protein interactions. The majority of these methods either require disruption of the cells to detect molecular interactions or rely on indirect detection of the protein interaction. The bimolecular fluorescence complementation (BiFC) assay provides a direct approach for the visualization of molecular interactions in living cells and organisms. The BiFC approach is based on the facilitated association between two fragments of a fluorescent protein when the fragments are brought together by an interaction between proteins fused to the fragments. The BiFC approach has been used for visualization of interactions among a variety of structurally diverse interaction partners in many different cell types. It enables detection of transient complexes as well as complexes formed by a subpopulation of the interaction partners. It is essential to include negative controls in each experiment in which the interface between the interaction partners has been mutated or deleted. The BiFC assay has been adapted for simultaneous visualization of multiple protein complexes in the same cell and the competition for shared interaction partners. A ubiquitin-mediated fluorescence complementation assay has also been developed for visualization of the covalent modification of proteins by ubiquitin family peptides. These fluorescence complementation assays have a great potential to illuminate a variety of biological interactions in the future.

Rehabilitation Services for Rural Blind Persons in Malaysia.

ERIC Educational Resources Information Center

Ooi, G.

1990-01-01

The article traces the experiences of the Malaysian Association for the Blind in developing rehabilitation services for rural blind persons. It explains the rationale for a community-based approach to rehabilitation and concludes that center-based and community-based approaches to rehabilitation complement each other in bringing services to rural…

Comparison between Perceptual Assessments of Nasality and Nasalance Scores

ERIC Educational Resources Information Center

Brunnegard, Karin; Lohmander, Anette; van Doorn, Jan

2012-01-01

Background: There are different reports of the usefulness of the Nasometer[TM] as a complement to listening, often as correlation calculations between listening and nasalance measurements. Differences between findings have been attributed to listener experience and types of speech stimuli. Aims: To compare nasalance scores from the Nasometer with…

Tests of Behavioral-Economic Assessments of Relative Reinforcer Efficacy II: Economic Complements

ERIC Educational Resources Information Center

Madden, Gregory J.; Smethells, John R.; Ewan, Eric E.; Hursh, Steven R.

2007-01-01

This experiment was conducted to test the predictions of two behavioral-economic approaches to quantifying relative reinforcer efficacy. The normalized demand analysis suggests that characteristics of averaged normalized demand curves may be used to predict progressive-ratio breakpoints and peak responding. By contrast, the demand analysis holds…

Cultural Considerations for Evaluation Consulting in the Egyptian Context.

ERIC Educational Resources Information Center

Seefeldt, Michael F.

1985-01-01

Reflecting on his experiences as an evaluation consultant at the Suez Canal University Faculty of Medicine in Egypt the author discusses: (1) implications of the Egyptian political context; (2) adapting to the host culture; and (3) maintaining distance from one's own culture. Personal qualities to complement the recommended naturalistic methods…

Awareness of Verb Subcategorization Probabilities with Polysemous Verbs: The Second Language Situation

ERIC Educational Resources Information Center

Uckun, Berrin

2012-01-01

Different meanings of a verb are associated with different argument structures (subcategorization), which in this study are sentential complements (SC) and direct object (DO) arguments. Interaction between verbal meaning and argument structure is investigated at the production level using polysemous verbs in the absence (Norming Experiment) and…

Enhancing the College Student Experience: Outcomes of a Leisure Education Program

ERIC Educational Resources Information Center

Jordan, Katherine A.; Gagnon, Ryan J.; Anderson, Denise M.; Pilcher, June J.

2018-01-01

Background: Experiential education in higher education provides opportunities for college student development that contribute to student success. As such, a leisure education program is posited as a complement to experiential education programming. Purpose: This study explored the impact of a leisure education program (leisure skills) on…

Exploring the Atmosphere Using Smartphones

ERIC Educational Resources Information Center

Monteiro, Martin; Vogt, Patrik; Stari, Cecilia; Cabeza, Cecilia; Marti, Arturo C.

2016-01-01

The characteristics of the inner layer of the atmosphere, the troposphere, are determinant for Earth's life. In this experience we explore the first hundreds of meters using a smartphone mounted on a quadcopter. Both the altitude and the pressure are obtained using the smartphone's sensors. We complement these measures with data collected from the…

Biomedical Research Experiences for Biology Majors at a Small College

ERIC Educational Resources Information Center

Stover, Shawn K.; Mabry, Michelle L.

2010-01-01

A program-level assessment of the biology curriculum at a small liberal arts college validates a previous study demonstrating success in achieving learning outcomes related to content knowledge and communication skills. Furthermore, research opportunities have been provided to complement pedagogical strategies and give students a more complete…

Integrating Technology into the Montessori Elementary Classroom.

ERIC Educational Resources Information Center

Hubbell, Elizabeth Ross

2003-01-01

Asserts that if used correctly, with forethought and respect to the Montessori philosophy, technology will advance and complement the experiences made available to children. Addresses the integration of technology into the Montessori elementary classroom focusing on the learning environment and the reduction of teacher time spent on tedious tasks.…

Case-Based Web Learning Versus Face-to-Face Learning: A Mixed-Method Study on University Nursing Students.

PubMed

Chan, Aileen Wai-Kiu; Chair, Sek-Ying; Sit, Janet Wing-Hung; Wong, Eliza Mi-Ling; Lee, Diana Tze-Fun; Fung, Olivia Wai-Man

2016-03-01

Case-based learning (CBL) is an effective educational method for improving the learning and clinical reasoning skills of students. Advances in e-learning technology have supported the development of the Web-based CBL approach to teaching as an alternative or supplement to the traditional classroom approach. This study aims to examine the CBL experience of Hong Kong students using both traditional classroom and Web-based approaches in undergraduate nursing education. This experience is examined in terms of the perceived self-learning ability, clinical reasoning ability, and satisfaction in learning of these students. A mixture of quantitative and qualitative approaches was adopted. All Year-3 undergraduate nursing students were recruited. CBL was conducted using the traditional classroom approach in Semester 1, and the Web-based approach was conducted in Semester 2. Student evaluations were collected at the end of each semester using a self-report questionnaire. In-depth, focus-group interviews were conducted at the end of Semester 2. One hundred twenty-two students returned their questionnaires. No difference between the face-to-face and Web-based approaches was found in terms of self-learning ability (p = .947), clinical reasoning ability (p = .721), and satisfaction (p = .083). Focus group interview findings complemented survey findings and revealed five themes that reflected the CBL learning experience of Hong Kong students. These themes were (a) the structure of CBL, (b) the learning environment of Web-based CBL, (c) critical thinking and problem solving, (d) cultural influence on CBL learning experience, and (e) student-centered and teacher-centered learning. The Web-based CBL approach was comparable but not superior to the traditional classroom CBL approach. The Web-based CBL experience of these students sheds light on the impact of Chinese culture on student learning behavior and preferences.

Molecular dynamics simulations of propane in slit shaped silica nano-pores: direct comparison with quasielastic neutron scattering experiments.

PubMed

Gautam, Siddharth; Le, Thu; Striolo, Alberto; Cole, David

2017-12-13

Molecular motion under confinement has important implications for a variety of applications including gas recovery and catalysis. Propane confined in mesoporous silica aerogel as studied using quasielastic neutron scattering (QENS) showed anomalous pressure dependence in its diffusion coefficient (J. Phys. Chem. C, 2015, 119, 18188). Molecular dynamics (MD) simulations are often employed to complement the information obtained from QENS experiments. Here, we report an MD simulation study to probe the anomalous pressure dependence of propane diffusion in silica aerogel. Comparison is attempted based on the self-diffusion coefficients and on the time scales of the decay of the simulated intermediate scattering functions. While the self-diffusion coefficients obtained from the simulated mean squared displacement profiles do not exhibit the anomalous pressure dependence observed in the experiments, the time scales of the decay of the intermediate scattering functions calculated from the simulation data match the corresponding quantities obtained in the QENS experiment and thus confirm the anomalous pressure dependence of the diffusion coefficient. The origin of the anomaly in pressure dependence lies in the presence of an adsorbed layer of propane molecules that seems to dominate the confined propane dynamics at low pressure, thereby lowering the diffusion coefficient. Further, time scales for rotational motion obtained from the simulations explain the absence of rotational contribution to the QENS spectra in the experiments. In particular, the rotational motion of the simulated propane molecules is found to exhibit large angular jumps at lower pressure. The present MD simulation work thus reveals important new insights into the origin of anomalous pressure dependence of propane diffusivity in silica mesopores and supplements the information obtained experimentally by QENS data.

Isolation and complementation analysis of 10 methanol oxidation mutant classes and identification of the methanol dehydrogenase structural gene of Methylobacterium sp. strain AM1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nunn, D.N.; Lidstrom, M.E.

A method has been developed for the direct selection of methanol oxidation mutants of the facultative methylotroph Methylobacterium sp. strain AM1 (formerly Pseudomonas sp. strain AM1). Using this direct selection technique, we have isolated mutants of Methylobacterium sp. strain AM1 that are no longer capable of growth on methanol but retain the ability to grow on methylamine. These methanol oxidation (Mox) mutants were complemented with a genomic clone bank of this organism constructed in the broad-host-range cosmid pVK100, and subcloning and Tn5 mutagenesis experiments have assigned the Mox mutants to 10 distinct complementation groups. Using an open reading frame beta-galactosidasemore » fusion vector and antibodies specific for Methylobacterium sp. strain AM1 methanol dehydrogenase, we have identified the methanol dehydrogenase structural gene and determined the direction of transcription. The results suggest that the synthesis and utilization of an active methanol dehydrogenase in this organism requires at least 10 different gene functions.« less

An experimental and three-dimensional computational study on the aerodynamic contribution to the passive pitching motion of flapping wings in hovering flies.

PubMed

Ishihara, D; Horie, T; Niho, T

2014-11-07

The relative importance of the wing's inertial and aerodynamic forces is the key to revealing how the kinematical characteristics of the passive pitching motion of insect flapping wings are generated, which is still unclear irrespective of its importance in the design of insect-like micro air vehicles. Therefore, we investigate three species of flies in order to reveal this, using a novel fluid-structure interaction analysis that consists of a dynamically scaled experiment and a three-dimensional finite element analysis. In the experiment, the dynamic similarity between the lumped torsional flexibility model as a first approximation of the dipteran wing and the actual insect is measured by the Reynolds number Re, the Strouhal number St, the mass ratio M, and the Cauchy number Ch. In the computation, the three-dimension is important in order to simulate the stable leading edge vortex and lift force in the present Re regime over 254. The drawback of the present experiment is the difficulty in satisfying the condition of M due to the limitation of available solid materials. The novelty of the present analysis is to complement this drawback using the computation. We analyze the following two cases: (a) The equilibrium between the wing's elastic and fluid forces is dynamically similar to that of the actual insect, while the wing's inertial force can be ignored. (b) All forces are dynamically similar to those of the actual insect. From the comparison between the results of cases (a) and (b), we evaluate the contributions of the equilibrium between the aerodynamic and the wing's elastic forces and the wing's inertial force to the passive pitching motion as 80-90% and 10-20%, respectively. It follows from these results that the dipteran passive pitching motion will be based on the equilibrium between the wing's elastic and aerodynamic forces, while it will be enhanced by the wing's inertial force.

Building a Program of University Physics and Mathematics Education

NASA Astrophysics Data System (ADS)

Tanaka, Tadayoshi; Nakamura, Akira; Kagiyama, Shigenori; Namiki, Masatoshi; Ejiri, Arisato; Ohshima, Kazunari; Mishima, Akiomi; Aoki, Katsuhiko

Authors built physics learning modules which consist of lectures, experiments and practices, introducing physics experiments of elementary and secondary education. In addition, we are operating "KIT Mathematics Navigation" in order to complement mathematical basics to engineering education. Based on these results, we are building studies and development of an education program in order to support the learning paradigm shift and to help students learn physics and mathematics complimentarily for liberal arts education course in universities.

Identification of a rice metal tolerance protein OsMTP11 as a manganese transporter

PubMed Central

Zhang, Mei; Liu, Baoxiu

2017-01-01

Metal tolerance proteins (MTPs) are a gene family of cation efflux transporters that occur widely in plants and might serve an essential role in metal homeostasis and tolerance. Our research describes the identification, characterization, and localization of OsMTP11, a member of the MTP family from rice. OsMTP11 was expressed constitutively and universally in different tissues in rice plant. Heterologous expression in yeast showed that OsMTP11 complemented the hypersensitivity of mutant strains to Mn, and also complemented yeast mutants to other metals, including Co and Ni. Real time RT-PCR analysis demonstrated OsMTP11 expression was substantially enhanced following 4 h under Cd, Zn, Ni, and Mn treatments, suggesting possible roles of OsMTP11 involvement in heavy metal stress responses. Promoter analysis by transgenic assays with GUS as a reporter gene and mRNA in situ hybridization experiments showed that OsMTP11 was expressed specifically in conducting tissues in rice. DNA methylation assays of genomic DNA in rice treated with Cd, Zn, Ni, and Mn revealed that decreased DNA methylation levels were present in the OsMTP11 promoter region, which was consistent with OsMTP11 induced-expression patterns resulting from heavy metal stress. This result suggested that DNA methylation is one of major factors regulating expression of OsMTP11 through epigenetic mechanisms. OsMTP11 fused to green fluorescent protein (GFP) localized to the entire onion epidermal cell cytoplasm, while vacuolar membrane exhibited increased GFP signals, consistent with an OsMTP11 function in cation sequestration. Our results indicated that OsMTP11 might play vital roles in Mn and other heavy metal transportation in rice. PMID:28394944

Functional Characterization of Promoter Variants of the Adiponectin Gene Complemented by Epidemiological Data

PubMed Central

Laumen, Helmut; Saningong, Akuma D.; Heid, Iris M.; Hess, Jochen; Herder, Christian; Claussnitzer, Melina; Baumert, Jens; Lamina, Claudia; Rathmann, Wolfgang; Sedlmeier, Eva-Maria; Klopp, Norman; Thorand, Barbara; Wichmann, H.-Erich; Illig, Thomas; Hauner, Hans

2009-01-01

OBJECTIVE Adiponectin (APM1, ACDC) is an adipocyte-derived protein with downregulated expression in obesity and insulin-resistant states. Several potentially regulatory single nucleotide polymorphisms (SNPs) within the APM1 gene promoter region have been associated with circulating adiponectin levels. None of them have been functionally characterized in adiponectin-expressing cells. Hence, we investigated three SNPs (rs16861194, rs17300539, and rs266729) for their influence on adiponectin promoter activity and their association with circulating adiponectin levels. RESEARCH DESIGN AND METHODS Basal and rosiglitazone-induced promoter activity of different SNP combinations (haplotypes) was analyzed in 3T3-L1 adipocytes using luciferase reporter gene assays and DNA binding studies comparing all possible APM1 haplotypes. This functional approach was complemented with analysis of epidemiological population-based data of 1,692 participants of the MONICA/KORA S123 cohort and 696 participants from the KORA S4 cohort for SNP and haplotype association with circulating adiponectin levels. RESULTS Major to minor allele replacements of the three SNPs revealed significant effects on promoter activity in luciferase assays. Particularly, a minor variant in rs16861194 resulted in reduced basal and rosiglitazone-induced promoter activity and hypoadiponectinemia in the epidemiological datasets. The haplotype with the minor allele in all three SNPs showed a complete loss of promoter activity, and no subject carried this haplotype in either of the epidemiological samples (combined P value for statistically significant difference from a random sample was 0.006). CONCLUSIONS Our results clearly demonstrate that promoter variants associated with hypoadiponectinemia in humans substantially affect adiponectin promoter activity in adipocytes. Our combination of functional experiments with epidemiological data overcomes the drawback of each approach alone. PMID:19074982

[Fuzzy mathematic quantitative law of composing principle in the study of traditional Chinese medicine].

PubMed

Liu, Ming; Gao, Yue; Xiao, Rui; Zhang, Bo-li

2009-01-01

This study is to analyze microcosmic significance of Chinese medicine composing principle "principal, assistant, complement and mediating guide" and it's fuzzy mathematic quantitative law. According to molecular biology and maximal membership principle, fuzzy subset and membership functions were proposed. Using in vivo experiment on the effects of SiWu Decoction and its ingredients on mice with radiation-induced blood deficiency, it is concluded that DiHuang and DangGui belonged to the principal and assistant subset, BaiShao belonged to the contrary complement subset, ChuanXiong belonged to the mediating guide subset by maximal membership principle. It is discussed that traditional Chinese medicine will be consummate medical science when its theory can be described by mathematic language.

Nuclear domain 10 components promyelocytic leukemia protein and hDaxx independently contribute to an intrinsic antiviral defense against human cytomegalovirus infection.

PubMed

Tavalai, Nina; Papior, Peer; Rechter, Sabine; Stamminger, Thomas

2008-01-01

Infection with DNA viruses commonly results in the association of viral genomes with a cellular subnuclear structure known as nuclear domain 10 (ND10). Recent studies demonstrated that individual ND10 components, like hDaxx or promyelocytic leukemia protein (PML), mediate an intrinsic immune response against human cytomegalovirus (HCMV) infection, strengthening the assumption that ND10 components are part of a cellular antiviral defense mechanism. In order to further define the role of hDaxx and PML for HCMV replication, we generated either primary human fibroblasts with a stable, individual knockdown of PML or hDaxx (PML-kd and hDaxx-kd, respectively) or cells exhibiting a double knockdown. Comparative analysis of HCMV replication in PML-kd or hDaxx-kd cells revealed that immediate-early (IE) gene expression increased to a similar extent, regardless of which ND10 constituent was depleted. Since a loss of PML, the defining component of ND10, results in a dispersal of the entire nuclear substructure, the increased replication efficacy of HCMV in PML-kd cells could be a consequence of the dissociation of the repressor protein hDaxx from its optimal subnuclear localization. However, experiments using three different recombinant HCMVs revealed a differential growth complementation in PML-kd versus hDaxx-kd cells, strongly arguing for an independent involvement in suppressing HCMV replication. Furthermore, infection experiments using double-knockdown cells devoid of both PML and hDaxx illustrated an additional enhancement in the replication efficacy of HCMV compared to the single-knockdown cells. Taken together, our data indicate that both proteins, PML and hDaxx, mediate an intrinsic immune response against HCMV infection by contributing independently to the silencing of HCMV IE gene expression.

CovR Regulates Streptococcus mutans Susceptibility To Complement Immunity and Survival in Blood

PubMed Central

Alves, Lívia A.; Nomura, Ryota; Mariano, Flávia S.; Harth-Chu, Erika N.; Stipp, Rafael N.; Nakano, Kazuhiko

2016-01-01

Streptococcus mutans, a major pathogen of dental caries, may promote systemic infections after accessing the bloodstream from oral niches. In this study, we investigate pathways of complement immunity against S. mutans and show that the orphan regulator CovR (CovRSm) modulates susceptibility to complement opsonization and survival in blood. S. mutans blood isolates showed reduced susceptibility to C3b deposition compared to oral isolates. Reduced expression of covRSm in blood strains was associated with increased transcription of CovRSm-repressed genes required for S. mutans interactions with glucans (gbpC, gbpB, and epsC), sucrose-derived exopolysaccharides (EPS). Consistently, blood strains showed an increased capacity to bind glucan in vitro. Deletion of covRSm in strain UA159 (UAcov) impaired C3b deposition and binding to serum IgG and C-reactive protein (CRP) as well as phagocytosis through C3b/iC3b receptors and killing by neutrophils. Opposite effects were observed in mutants of gbpC, epsC, or gtfBCD (required for glucan synthesis). C3b deposition on UA159 was abolished in C1q-depleted serum, implying that the classical pathway is essential for complement activation on S. mutans. Growth in sucrose-containing medium impaired the binding of C3b and IgG to UA159, UAcov, and blood isolates but had absent or reduced effects on C3b deposition in gtfBCD, gbpC, and epsC mutants. UAcov further showed increased ex vivo survival in human blood in an EPS-dependent way. Consistently, reduced survival was observed for the gbpC and epsC mutants. Finally, UAcov showed an increased ability to cause bacteremia in a rat model. These results reveal that CovRSm modulates systemic virulence by regulating functions affecting S. mutans susceptibility to complement opsonization. PMID:27572331

The Number of X Chromosomes Causes Sex Differences in Adiposity in Mice

PubMed Central

Chen, Xuqi; McClusky, Rebecca; Chen, Jenny; Beaven, Simon W.; Tontonoz, Peter

2012-01-01

Sexual dimorphism in body weight, fat distribution, and metabolic disease has been attributed largely to differential effects of male and female gonadal hormones. Here, we report that the number of X chromosomes within cells also contributes to these sex differences. We employed a unique mouse model, known as the “four core genotypes,” to distinguish between effects of gonadal sex (testes or ovaries) and sex chromosomes (XX or XY). With this model, we produced gonadal male and female mice carrying XX or XY sex chromosome complements. Mice were gonadectomized to remove the acute effects of gonadal hormones and to uncover effects of sex chromosome complement on obesity. Mice with XX sex chromosomes (relative to XY), regardless of their type of gonad, had up to 2-fold increased adiposity and greater food intake during daylight hours, when mice are normally inactive. Mice with two X chromosomes also had accelerated weight gain on a high fat diet and developed fatty liver and elevated lipid and insulin levels. Further genetic studies with mice carrying XO and XXY chromosome complements revealed that the differences between XX and XY mice are attributable to dosage of the X chromosome, rather than effects of the Y chromosome. A subset of genes that escape X chromosome inactivation exhibited higher expression levels in adipose tissue and liver of XX compared to XY mice, and may contribute to the sex differences in obesity. Overall, our study is the first to identify sex chromosome complement, a factor distinguishing all male and female cells, as a cause of sex differences in obesity and metabolism. PMID:22589744

Design, synthesis, and evaluation of A/C/D-ring analogs of the fungal metabolite K-76 as potential complement inhibitors.

PubMed

Kaufman, T S; Srivastava, R P; Sindelar, R D; Scesney, S M; Marsh, H C

1995-04-28

The terpenoid 6,7-diformyl-3',4',4a',5',6',7',8',8a'-octahydro-4,6',7'-trihydrox y-2',5',5', 8a'-tetramethylspiro[1'(2'H)-naphthalene-2(3H)-benzofuran] (1a; K-76), a natural product of fungal origin, and its monocarboxylate sodium salt 1c (R = COONa; K-76COONa) inhibit the classical and alternative pathways of complement, and 1c was shown to inhibit the classical pathway at the C5 activation step. In an attempt to elucidate the essential pharmacophore of 1a,c, the natural product was used as a "topographical model" for the design of partial analogs retaining the desired complement inhibiting potency. Therefore, A/C/D-ring analogs have been synthesized, as shown in Scheme 1 using 3-methoxyphenol (3) and limonene chloride (5) as starting materials, which contain functional groups similar to those found on the natural product. The use of (4R)-(+)- and (4S)(-)-limonene chloride (5a,b, respectively) provided two series of compounds differing in the stereochemistry of the C-4 chiral center (limonene moiety numbering). The in vitro assay results of the inhibition of anaphylatoxin production and classical complement-mediated hemolysis revealed that 7-carboxy-2-(R,S)-methyl-2-(1'-methylcyclohexen-(4'R)-yl)-4-met hoxybenzofuran (13a) and 7-carboxy-2-(R,S)-methyl-2-(1'-methylcyclohexen-(4'S)-yl)-4-met hoxybenzofuran (13b) were active in the same range of concentrations as the natural product.

Laboratory activity to effectively teach introductory geomicrobiology concepts to non-geology majors.

PubMed

Marvasi, Massimiliano; Davila-Vazquez, Yarely C; Martinez, Lilliam Casillas

2013-01-01

We have designed a three-week experiment that can complement any microbiology course, to teach main geomicrobiology concepts for non-geology majors. One of the most difficult concepts for non-geology majors to comprehend is how bacteria serve as a platform for different mineralization reactions. In our three-week laboratory practice, students learn the main principles and conditions required for an induced bacterial mineralization. Upon completion of the laboratory experience, students will: 1) learn how microbial-induced mineralization (such as calcium carbonate formation) is affected by differential media and growth conditions; 2) understand how bacterial physiology affects any induced in situ or in vitro mineralization; 3) comprehend how growing conditions and bacterial physiologies interrelate, resulting in differential crystal formation. The teaching-learning process was assessed using a pre-/posttest with an increase from 26% to 76% in the number of positive answers from the students. We also measured the students' proficiency while conducting specific technical tasks, revealing no major difficulties while conducting the experiments. A final questionnaire was provided with satisfactory evaluations from the students regarding the organization and content of the practices. 84-86% of the students agreed that the exercises improved their knowledge in geomicrobiology and would like to attend similar laboratories in the future. Such response is the best indicator that the laboratory practice can be implemented in any undergraduate/graduate microbiology course to effectively teach basic geomicrobiology concepts to non-geology majors.

Laboratory Activity to Effectively Teach Introductory Geomicrobiology Concepts to Non-Geology Majors †

PubMed Central

Marvasi, Massimiliano; Davila-Vazquez, Yarely C.; Martinez, Lilliam Casillas

2013-01-01

We have designed a three-week experiment that can complement any microbiology course, to teach main geomicrobiology concepts for non-geology majors. One of the most difficult concepts for non-geology majors to comprehend is how bacteria serve as a platform for different mineralization reactions. In our three-week laboratory practice, students learn the main principles and conditions required for an induced bacterial mineralization. Upon completion of the laboratory experience, students will: 1) learn how microbial-induced mineralization (such as calcium carbonate formation) is affected by differential media and growth conditions; 2) understand how bacterial physiology affects any induced in situ or in vitro mineralization; 3) comprehend how growing conditions and bacterial physiologies interrelate, resulting in differential crystal formation. The teaching-learning process was assessed using a pre-/posttest with an increase from 26% to 76% in the number of positive answers from the students. We also measured the students’ proficiency while conducting specific technical tasks, revealing no major difficulties while conducting the experiments. A final questionnaire was provided with satisfactory evaluations from the students regarding the organization and content of the practices. 84–86% of the students agreed that the exercises improved their knowledge in geomicrobiology and would like to attend similar laboratories in the future. Such response is the best indicator that the laboratory practice can be implemented in any undergraduate/graduate microbiology course to effectively teach basic geomicrobiology concepts to non-geology majors. PMID:24358384

Examining the Role of Patient Experience Surveys in Measuring Health Care Quality

PubMed Central

Elliott, Marc N.; Zaslavsky, Alan M.; Hays, Ron D.; Lehrman, William G.; Rybowski, Lise; Edgman-Levitan, Susan; Cleary, Paul D.

2015-01-01

Patient care experience surveys evaluate the degree to which care is patient-centered. This article reviews the literature on the association between patient experiences and other measures of health care quality. Research indicates that better patient care experiences are associated with higher levels of adherence to recommended prevention and treatment processes, better clinical outcomes, better patient safety within hospitals, and less health care utilization. Patient experience measures that are collected using psychometrically sound instruments, employing recommended sample sizes and adjustment procedures, and implemented according to standard protocols are intrinsically meaningful and are appropriate complements for clinical process and outcome measures in public reporting and pay-for-performance programs. PMID:25027409

Functional Characterization of Soybean Glyma04g39610 as a Brassinosteroid Receptor Gene and Evolutionary Analysis of Soybean Brassinosteroid Receptors

PubMed Central

Peng, Suna; Tao, Ping; Xu, Feng; Wu, Aiping; Huo, Weige; Wang, Jinxiang

2016-01-01

Brassinosteroids (BR) play important roles in plant growth and development. Although BR receptors have been intensively studied in Arabidopsis, the BR receptors in soybean remain largely unknown. Here, in addition to the known receptor gene Glyma06g15270 (GmBRI1a), we identified five putative BR receptor genes in the soybean genome: GmBRI1b, GmBRL1a, GmBRL1b, GmBRL2a, and GmBRL2b. Analysis of their expression patterns by quantitative real-time PCR showed that they are ubiquitously expressed in primary roots, lateral roots, stems, leaves, and hypocotyls. We used rapid amplification of cDNA ends (RACE) to clone GmBRI1b (Glyma04g39160), and found that the predicted amino acid sequence of GmBRI1b showed high similarity to those of AtBRI1 and pea PsBRI1. Structural modeling of the ectodomain also demonstrated similarities between the BR receptors of soybean and Arabidopsis. GFP-fusion experiments verified that GmBRI1b localizes to the cell membrane. We also explored GmBRI1b function in Arabidopsis through complementation experiments. Ectopic over-expression of GmBRI1b in Arabidopsis BR receptor loss-of-function mutant (bri1-5 bak1-1D) restored hypocotyl growth in etiolated seedlings; increased the growth of stems, leaves, and siliques in light; and rescued the developmental defects in leaves of the bri1-6 mutant, and complemented the responses of BR biosynthesis-related genes in the bri1-5 bak1-D mutant grown in light. Bioinformatics analysis demonstrated that the six BR receptor genes in soybean resulted from three gene duplication events during evolution. Phylogenetic analysis classified the BR receptors in dicots and monocots into three subclades. Estimation of the synonymous (Ks) and the nonsynonymous substitution rate (Ka) and selection pressure (Ka/Ks) revealed that the Ka/Ks of BR receptor genes from dicots and monocots were less than 1.0, indicating that BR receptor genes in plants experienced purifying selection during evolution. PMID:27338344

KSC-03PD-0083

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. - Students work on their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03PD-0079

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. -- Students display an experiment that will fly in SPACEHAB on Space Shuttle Columbia on mission STS- 107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03PD-0087

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. - Students work on their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03PD-0086

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. - Students work on their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03PD-0081

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. - Students look over their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03PD-0088

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. - Students check out their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03PD-0082

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. - Students check on their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03PD-0084

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. - Students work on their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03PD-0094

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. -- Students work on their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03PD-0091

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. -- Students work on their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03PD-0090

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. -- Students check out their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03PD-0096

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. -- A student displays an experiment that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03PD-0097

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. -- Students display an experiment that will fly in SPACEHAB on Space Shuttle Columbia on mission STS- 107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03PD-0095

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. - A student works on an experiment that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0095

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. - A student works on an experiment that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0090

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. -- Students check out their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0082

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. - Students check on their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0084

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. - Students work on their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0088

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. - Students check out their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0094

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. -- Students work on their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0087

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. - Students work on their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0091

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. -- Students work on their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0097

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. -- Students display an experiment that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0083

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. - Students work on their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0086

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. - Students work on their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0096

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. -- A student displays an experiment that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

SPACEHAB - Space Shuttle Columbia mission STS-107

NASA Image and Video Library

2003-01-14

Students display an experiment that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0081

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. - Students look over their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

Mechanism of Promoter Melting by the Xeroderma Pigmentosum Complementation Group B Helicase of Transcription Factor IIH Revealed by Protein-DNA Photo-Cross-Linking

PubMed Central

Douziech, Maxime; Coin, Frédéric; Chipoulet, Jean-Marc; Arai, Yoko; Ohkuma, Yoshiaki; Egly, Jean-Marc; Coulombe, Benoit

2000-01-01

The p89/xeroderma pigmentosum complementation group B (XPB) ATPase-helicase of transcription factor IIH (TFIIH) is essential for promoter melting prior to transcription initiation by RNA polymerase II (RNAPII). By studying the topological organization of the initiation complex using site-specific protein-DNA photo-cross-linking, we have shown that p89/XPB makes promoter contacts both upstream and downstream of the initiation site. The upstream contact, which is in the region where promoter melting occurs (positions −9 to +2), requires tight DNA wrapping around RNAPII. The addition of hydrolyzable ATP tethers the template strand at positions −5 and +1 to RNAPII subunits. A mutation in p89/XPB found in a xeroderma pigmentosum patient impairs the ability of TFIIH to associate correctly with the complex and thereby melt promoter DNA. A model for open complex formation is proposed. PMID:11027286

A Nonsense Mutation in Mycobacterium marinum That Is Suppressible by a Novel Mechanism

PubMed Central

Williams, Emily A.; Mba Medie, Felix; Bosserman, Rachel E.; Johnson, Benjamin K.; Reyna, Cristal; Ferrell, Micah J.; Champion, Matthew M.; Abramovitch, Robert B.

2016-01-01

ABSTRACT Mycobacterial pathogens use the ESAT-6 system 1 (Esx-1) exporter to promote virulence. Previously, we used gene disruption and complementation to conclude that the MMAR_0039 gene in Mycobacterium marinum is required to promote Esx-1 export. Here we applied molecular genetics, proteomics, and whole-genome sequencing to demonstrate that the MMAR_0039 gene is not required for Esx-1 secretion or virulence. These findings suggest that we initially observed an indirect mechanism of genetic complementation. We identified a spontaneous nonsense mutation in a known Esx-1-associated gene which causes a loss of Esx-1 activity. We show that the Esx-1 function was restored by nonsense suppression. Moreover, we identified a polar mutation in the ppsC gene which reduced cellular impermeability but did not impact cytotoxicity in macrophages. Our studies reveal insight into Esx-1 export, nonsense suppression, and cell envelope lipid biogenesis. PMID:27789543

A widespread plant-fungal-bacterial symbiosis promotes plant biodiversity, plant nutrition and seedling recruitment.

PubMed

van der Heijden, Marcel G A; de Bruin, Susanne; Luckerhoff, Ludo; van Logtestijn, Richard S P; Schlaeppi, Klaus

2016-02-01

Highly diverse microbial assemblages colonize plant roots. It is still poorly understood whether different members of this root microbiome act synergistically by supplying different services (for example, different limiting nutrients) to plants and plant communities. In order to test this, we manipulated the presence of two widespread plant root symbionts, arbuscular mycorrhizal fungi and nitrogen-fixing rhizobia bacteria in model grassland communities established in axenic microcosms. Here, we demonstrate that both symbionts complement each other resulting in increased plant diversity, enhanced seedling recruitment and improved nutrient acquisition compared with a single symbiont situation. Legume seedlings obtained up to 15-fold higher productivity if they formed an association with both symbionts, opposed to productivity they reached with only one symbiont. Our results reveal the importance of functional diversity of symbionts and demonstrate that different members of the root microbiome can complement each other in acquiring different limiting nutrients and in driving important ecosystem functions.

Isolation of a complementary DNA clone for the human complement protein C2 and its use in the identification of a restriction fragment length polymorphism.

PubMed Central

Woods, D E; Edge, M D; Colten, H R

1984-01-01

Complementary DNA (cDNA) clones corresponding to the major histocompatibility (MHC) class III antigen, complement protein C2, have been isolated from human liver cDNA libraries with the use of a complex mixture of synthetic oligonucleotides (17 mer) that contains 576 different oligonucleotide sequences. The C2 cDNA were used to identify a DNA restriction enzyme fragment length polymorphism that provides a genetic marker within the MHC that was not detectable at the protein level. An extensive search for genomic polymorphisms using a cDNA clone for another MHC class III gene, factor B, failed to reveal any DNA variants. The genomic variants detected with the C2 cDNA probe provide an additional genetic marker for analysis of MHC-linked diseases. Images PMID:6086718

TolC is required for pathogenicity of Xylella fastidiosa in Vitis vinifera grapevines.

PubMed

Reddy, Joseph D; Reddy, Stephanie L; Hopkins, Don L; Gabriel, Dean W

2007-04-01

Xylella fastidiosa infects a wide range of hosts and causes serious diseases on some of them. The complete genomic sequences of both a citrus variegated chlorosis (CVC) and a Pierce's disease (PD) strain revealed two type I protein secretion plus two multidrug resistance efflux systems, and all evidently were dependent on a single tolC homolog. Marker exchange mutagenesis of the single tolC gene in PD strain Temecula resulted in a total loss of pathogenicity on grape. Importantly, the tolC- mutant strains were not recovered after inoculation into grape xylem, strongly indicating that multidrug efflux is critical to survival of this fastidious pathogen. Both survival and pathogenicity were restored by complementation using tolC cloned in shuttle vector pBBR1MCS-5, which was shown to replicate autonomously, without selection, for 60 days in Temecula growing in planta. These results also demonstrate the ability to complement mutations in X. fastidiosa.

Construction of broad-host-range cosmid cloning vectors: identification of genes necessary for growth of Methylobacterium organophilum on methanol

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allen, L.N.; Hanson, R.S.

Four new cloning vectors have been constructed from the broad-host-range cloning vector pRK290. These vectors, pLA2901, pLA2905, pLA2910, and pLA2917, confer resistance to kanamycin and tetracycline. The latter two are cosmid derivatives of pLA2901. The new vectors can be mobilized into, and are stably maintained in, a variety of gram-negative bacteria. A Sau3A genomic bank of Methylobacterium organophilum strain xx DNA has been constructed in pLA2917, and complementation analysis, with a variety of mutants unable to grow on methanol, revealed at least five separate regions necessary for growth on methanol. Complementation analysis and Tn5 mutagenesis data suggest that at leastmore » three genes are responsible for expression of active methanol dehydrogenase.« less

Is the Fungus Magnaporthe Losing DNA Methylation?

PubMed Central

Ikeda, Ken-ichi; Van Vu, Ba; Kadotani, Naoki; Tanaka, Masaki; Murata, Toshiki; Shiina, Kohta; Chuma, Izumi; Tosa, Yukio; Nakayashiki, Hitoshi

2013-01-01

The long terminal repeat retrotransposon, Magnaporthe gypsy-like element (MAGGY), has been shown to be targeted for cytosine methylation in a subset of Magnaporthe oryzae field isolates. Analysis of the F1 progeny from a genetic cross between methylation-proficient (Br48) and methylation-deficient (GFSI1-7-2) isolates revealed that methylation of the MAGGY element was governed by a single dominant gene. Positional cloning followed by gene disruption and complementation experiments revealed that the responsible gene was the DNA methyltransferase, MoDMT1, an ortholog of Neurospora crassa Dim-2. A survey of MAGGY methylation in 60 Magnaporthe field isolates revealed that 42 isolates from rice, common millet, wheat, finger millet, and buffelgrass were methylation proficient while 18 isolates from foxtail millet, green bristlegrass, Japanese panicgrass, torpedo grass, Guinea grass, and crabgrass were methylation deficient. Phenotypic analyses showed that MoDMT1 plays no major role in development and pathogenicity of the fungus. Quantitative polymerase chain reaction analysis showed that the average copy number of genomic MAGGY elements was not significantly different between methylation-deficient and -proficient field isolates even though the levels of MAGGY transcript were generally higher in the former group. MoDMT1 gene sequences in the methylation-deficient isolates suggested that at least three independent mutations were responsible for the loss of MoDMT1 function. Overall, our data suggest that MoDMT1 is not essential for the natural life cycle of the fungus and raise the possibility that the genus Magnaporthe may be losing the mechanism of DNA methylation on the evolutionary time scale. PMID:23979580

A Novel Bacteriophage Targeting Cronobacter sakazakii Is a Potential Biocontrol Agent in Foods

PubMed Central

Lee, Ju-Hoon; Bai, Jaewoo; Shin, Hakdong; Kim, Yeran; Park, Bookyung; Heu, Sunggi

2015-01-01

Cronobacter sakazakii is an important pathogen that causes high mortality in infants. Due to its occasional antibiotic resistance, a bacteriophage approach might be an alternative effective method for the control of this pathogen. To develop a novel biocontrol agent using bacteriophages, the C. sakazakii-infecting phage CR5 was newly isolated and characterized. Interestingly, this phage exhibited efficient and relatively durable host lysis activity. In addition, a specific gene knockout study and subsequent complementation experiment revealed that this phage infected the host strain using the bacterial flagella. The complete genome sequence analysis of phage CR5 showed that its genome contains 223,989 bp of DNA, including 231 predicted open reading frames (ORFs), and it has a G+C content of 50.06%. The annotated ORFs were classified into six functional groups (structure, packaging, host lysis, DNA manipulation, transcription, and additional functions); no gene was found to be related to virulence or toxin or lysogen formation, but >80% of the predicted ORFs are unknown. In addition, a phage proteomic analysis using SDS-PAGE and matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) revealed that seven phage structural proteins are indeed present, supporting the ORF predictions. To verify the potential of this phage as a biocontrol agent against C. sakazakii, it was added to infant formula milk contaminated with a C. sakazakii clinical isolate or food isolate, revealing complete growth inhibition of the isolates by the addition of phage CR5 when the multiplicity of infection (MOI) was 105. PMID:26497465

Evidence for an anterior-posterior differentiation in the human hippocampal formation revealed by meta-analytic parcellation of fMRI coordinate maps: focus on the subiculum.

PubMed

Chase, Henry W; Clos, Mareike; Dibble, Sofia; Fox, Peter; Grace, Anthony A; Phillips, Mary L; Eickhoff, Simon B

2015-06-01

Previous studies, predominantly in experimental animals, have suggested the presence of a differentiation of function across the hippocampal formation. In rodents, ventral regions are thought to be involved in emotional behavior while dorsal regions mediate cognitive or spatial processes. Using a combination of modeling the co-occurrence of significant activations across thousands of neuroimaging experiments and subsequent data-driven clustering of these data we were able to provide evidence of distinct subregions within a region corresponding to the human subiculum, a critical hub within the hippocampal formation. This connectivity-based model consists of a bilateral anterior region, as well as separate posterior and intermediate regions on each hemisphere. Functional connectivity assessed both by meta-analytic and resting fMRI approaches revealed that more anterior regions were more strongly connected to the default mode network, and more posterior regions were more strongly connected to 'task positive' regions. In addition, our analysis revealed that the anterior subregion was functionally connected to the ventral striatum, midbrain and amygdala, a circuit that is central to models of stress and motivated behavior. Analysis of a behavioral taxonomy provided evidence for a role for each subregion in mnemonic processing, as well as implication of the anterior subregion in emotional and visual processing and the right posterior subregion in reward processing. These findings lend support to models which posit anterior-posterior differentiation of function within the human hippocampal formation and complement other early steps toward a comparative (cross-species) model of the region. Copyright © 2015 Elsevier Inc. All rights reserved.

Kinetic parameters of grinding media in ball mills with various liner design and mill speed based on DEM modeling

NASA Astrophysics Data System (ADS)

Khakhalev, P. A.; Bogdanov, VS; Kovshechenko, V. M.

2018-03-01

The article presents analysis of the experiments in the ball mill of 0.5x0.3 m with four different liner types based on DEM modeling. The numerical experiment always complements laboratory research and allow obtaining high accuracy output data. An important property of the numerical experiment is the possibility of visualization of the results. The EDEM software allows calculating trajectory of the grinding bodies and kinetic parameters of each ball for the relative mill speed and the different types of mill’s liners.

OV-104's RMS releases Gamma Ray Observatory (GRO) during STS-37 deployment

NASA Image and Video Library

1991-04-07

Atlantis', Orbiter Vehicle (OV) 104's, remote manipulator system (RMS) releases Gamma Ray Observatory (GRO) during STS-37 deployment. Visible on the GRO as it drifts away from the RMS end effector are the four complement instruments: the Energetic Gamma Ray Experiment (bottom); Imaging Compton Telescope (COMPTEL) (center); Oriented Scintillation Spectrometer Experiment (OSSE) (top); and Burst and Transient Source Experiment (BATSE) (at four corners). GRO's solar array (SA) panels are extended and are in orbit configuration. View was taken through aft flight deck window which reflects some of the crew compartment interior.

Thermostability promotes the cooperative function of split adenylate kinases.

PubMed

Nguyen, Peter Q; Liu, Shirley; Thompson, Jeremy C; Silberg, Jonathan J

2008-05-01

Proteins can often be cleaved to create inactive polypeptides that associate into functional complexes through non-covalent interactions, but little is known about what influences the cooperative function of the ensuing protein fragments. Here, we examine whether protein thermostability affects protein fragment complementation by characterizing the function of split adenylate kinases from the mesophile Bacillus subtilis (AKBs) and the hyperthermophile Thermotoga neapolitana (AKTn). Complementation studies revealed that the split AKTn supported the growth of Escherichia coli with a temperature-sensitive AK, but not the fragmented AKBs. However, weak complementation occurred when the AKBs fragments were fused to polypeptides that strongly associate, and this was enhanced by a Q16L mutation that thermostabilizes the full-length protein. To examine how the split AK homologs differ in structure and function, their catalytic activity, zinc content, and circular dichroism spectra were characterized. The reconstituted AKTn had higher levels of zinc, greater secondary structure, and >10(3)-fold more activity than the AKBs pair, albeit 17-fold less active than full-length AKTn. These findings provide evidence that the design of protein fragments that cooperatively function can be improved by choosing proteins with the greatest thermostability for bisection, and they suggest that this arises because hyperthermophilic protein fragments exhibit greater residual structure compared to their mesophilic counterparts.

Complement component 3: characterization and association with mastitis resistance in Egyptian water buffalo and cattle.

PubMed

El-Halawany, Nermin; Abd-El-Monsif, Shawky A; Al-Tohamy Ahmed, F M; Hegazy, Lamees; Abdel-Shafy, Hamdy; Abdel-Latif, Magdy A; Ghazi, Yasser A; Neuhoff, Christiane; Salilew-Wondim, Dessie; Schellander, Karl

2017-03-01

Mastitis is an infectious disease of the mammary gland that leads to reduced milk production and change in milk composition. Complement component C3 plays a major role as a central molecule of the complement cascade involving in killing of microorganisms, either directly or in cooperation with phagocytic cells. C3 cDNA were isolated, from Egyptian buffalo and cattle, sequenced and characterized. The C3 cDNA sequences of buffalo and cattle consist of 5025 and 5019 bp, respectively. Buffalo and cattle C3 cDNAs share 99% of sequence identity with each other. The 4986 bp open reading frame in buffalo encodes a putative protein of 1661 amino acids-as in cattle-and includes all the functional domains. Further, analysis of the C3 cDNA sequences detected six novel single-nucleotide polymorphisms (SNPs) in buffalo and three novel SNPs in cattle. The association analysis of the detected SNPs with milk somatic cell score as an indicator of mastitis revealed that the most significant association in buffalo was found in the C>A substitution (ss: 1752816097) in exon 27, whereas in cattle it was in the C>T substitution (ss: 1752816085) in exon 12. Our findings provide preliminary information about the contribution of C3 polymorphisms to mastitis resistance in buffalo and cattle.

Human SAP is a novel peptidoglycan recognition protein that induces complement- independent phagocytosis of Staphylococcus aureus

PubMed Central

An, Jang-Hyun; Kurokawa, Kenji; Jung, Dong-Jun; Kim, Min-Jung; Kim, Chan-Hee; Fujimoto, Yukari; Fukase, Koichi; Coggeshall, K. Mark; Lee, Bok Luel

2014-01-01

The human pathogen Staphylococcus aureus is responsible for many community-acquired and hospital-associated infections and is associated with high mortality. Concern over the emergence of multidrug-resistant strains has renewed interest in the elucidation of host mechanisms that defend against S. aureus infection. We recently demonstrated that human serum mannose-binding lectin (MBL) binds to S. aureus wall teichoic acid (WTA), a cell wall glycopolymer, a discovery that prompted further screening to identify additional serum proteins that recognize S. aureus cell wall components. In this report, we incubated human serum with 10 different S. aureus mutants and determined that serum amyloid P component (SAP) bound specifically to a WTA-deficient S. aureus ΔtagO mutant, but not to tagO-complemented, WTA-expressing cells. Biochemical characterization revealed that SAP recognizes bacterial peptidoglycan as a ligand and that WTA inhibits this interaction. Although SAP binding to peptidoglycan was not observed to induce complement activation, SAP-bound ΔtagO cells were phagocytosed by human polymorphonuclear leukocytes in an Fcγ receptor-dependent manner. These results indicate that SAP functions as a host defense factor, similar to other peptidoglycan recognition proteins and nucleotide-binding oligomerization domain (NOD)-like receptors. PMID:23966633

Prediction of protein interaction hot spots using rough set-based multiple criteria linear programming.

PubMed

Chen, Ruoying; Zhang, Zhiwang; Wu, Di; Zhang, Peng; Zhang, Xinyang; Wang, Yong; Shi, Yong

2011-01-21

Protein-protein interactions are fundamentally important in many biological processes and it is in pressing need to understand the principles of protein-protein interactions. Mutagenesis studies have found that only a small fraction of surface residues, known as hot spots, are responsible for the physical binding in protein complexes. However, revealing hot spots by mutagenesis experiments are usually time consuming and expensive. In order to complement the experimental efforts, we propose a new computational approach in this paper to predict hot spots. Our method, Rough Set-based Multiple Criteria Linear Programming (RS-MCLP), integrates rough sets theory and multiple criteria linear programming to choose dominant features and computationally predict hot spots. Our approach is benchmarked by a dataset of 904 alanine-mutated residues and the results show that our RS-MCLP method performs better than other methods, e.g., MCLP, Decision Tree, Bayes Net, and the existing HotSprint database. In addition, we reveal several biological insights based on our analysis. We find that four features (the change of accessible surface area, percentage of the change of accessible surface area, size of a residue, and atomic contacts) are critical in predicting hot spots. Furthermore, we find that three residues (Tyr, Trp, and Phe) are abundant in hot spots through analyzing the distribution of amino acids. Copyright © 2010 Elsevier Ltd. All rights reserved.

Discovery of an operon that participates in agmatine metabolism and regulates biofilm formation in Pseudomonas aeruginosa

PubMed Central

Williams, Bryan J.; Du, Rui-Hong; Calcutt, M. Wade; Abdolrasulnia, Rasul; Christman, Brian W.; Blackwell, Timothy S.

2013-01-01

Summary Agmatine is the decarboxylation product of arginine and a number of bacteria have devoted enzymatic pathways for its metabolism. Pseudomonas aeruginosa harbours the aguBA operon that metabolizes agmatine to putrescine, which can be subsequently converted into other polyamines or shunted into the TCA cycle for energy production. We discovered an alternate agmatine operon in the P. aeruginosa strain PA14 named agu2ABCA′ that contains two genes for agmatine deiminases (agu2A and agu2A′). This operon was found to be present in 25% of clinical P. aeruginosa isolates. Agu2A′ contains a twin-arginine translocation signal at its N-terminus and site-directed mutagenesis and cell fractionation experiments confirmed this protein is secreted to the periplasm. Analysis of the agu2ABCA′ promoter demonstrates that agmatine induces expression of the operon during the stationary phase of growth and during biofilm growth and agu2ABCA′ provides only weak complementation of aguBA, which is induced during log phase. Biofilm assays of mutants of all three agmatine deiminase genes in PA14 revealed that deletion of agu2ABCA′, specifically its secreted product Agu2A′, reduces biofilm production of PA14 following addition of exogenous agmatine. Together, these findings reveal a novel role for the agu2ABCA′ operon in the biofilm development of P. aeruginosa. PMID:20149107

Measurement of nurses' attitudes and knowledge regarding acute care older patients: Psychometrics of the OPACS-US combined with the KOP-Q.

PubMed

Dikken, Jeroen; Hoogerduijn, Jita G; Lagerwey, Mary D; Shortridge-Baggett, Lillie; Klaassen, Sharon; Schuurmans, Marieke J

In clinical practice, identifying positive and negative attitudes toward older patients is very important to improve quality of care provided to them. The Older People in Acute Care Survey - United States (OPACS-US) is an instrument measuring hospital nurses attitudes regarding older patients. However, psychometrics have never been assessed. Furthermore, knowledge being related to attitude and behavior should also be measured complementing the OPACS-US. The purpose of this study was to assess structural validity and reliability of the OPACS-US and assess whether the OPACS-US can be complemented with the Knowledge about Older Patients-Quiz (KOP-Q). A multicenter cross sectional design was conducted. Registered nurses (n = 130, mean age 39,9 years; working experience 14,6 years) working in four general hospitals were included in the study. Nurses completed the OPACS-US section A: practice experiences, B: general opinion and the KOP-Q online. Findings demonstrated that the OPACS-US is a valid and reliable survey instrument that measures practice experiences and general opinion. Furthermore, the OPACS-US can be combined with the KOP-Q adding a knowledge construct, and is ready for use within education and/or quality improvement programs in the USA. Copyright © 2017 Elsevier Inc. All rights reserved.

Using Low-Tech Interactions in the Chemistry Classroom to Engage Students in Active Learning

ERIC Educational Resources Information Center

Shaver, Michael P.

2010-01-01

Two complementary techniques to gauge student understanding and inspire interactive learning in the chemistry classroom are presented. Specifically, this article explores the use of student responses with their thumbs as an alternative to electronic-response systems and complementing these experiences with longer, task-based questions in an…

Ties That Bind: Communities in American History.

ERIC Educational Resources Information Center

Auel, Lisa B.

The communities that individuals have created are endlessly diverse. They have followed ancient patterns and have experimented boldly with innovative ideas. This publication and the exhibition it complements present only a few of the many ways that individuals have found to live together. It is divided according to the specific forces behind the…

Launch of STS-67 Space Shuttle Endeavour

NASA Technical Reports Server (NTRS)

1995-01-01

Carrying a crew of seven and a complement of astronomic experiments, the Space Shuttle Endeavour embarks on NASA's longest shuttle flight to date. Endeavour's liftoff from Launch Pad 39A occurred at 1:38:13 a.m. (EST), March 2, 1995. In this view the fence line near the launch pad is evident in the foreground.

Elementary Science Supplement to the Syllabus. Level I (Ages 4 through 7).

ERIC Educational Resources Information Center

New York State Education Dept., Albany.

Developed to complement existing elementary science programs, the materials in this first volume of New York's Elementary Science Supplement to the Syllabus emphasize a direct experience, hands-on approach for children of ages 4 through 7. Major sections include: (1) guidelines for program activities (explaining the organizational format of the…

Student Perceptions and Effectiveness of an Innovative Learning Tool: Anatomy Glove Learning System

ERIC Educational Resources Information Center

Lisk, Kristina; McKee, Pat; Baskwill, Amanda; Agur, Anne M. R.

2015-01-01

A trend in anatomical education is the development of alternative pedagogical approaches to replace or complement experiences in a cadaver laboratory; however, empirical evidence on their effectiveness is often not reported. This study aimed to evaluate the effectiveness of Anatomy Glove Learning System (AGLS), which enables students to learn the…

Curriculum Outline for a General Oceanography Field Laboratory (Review Cycle-Annual).

ERIC Educational Resources Information Center

Schlenker, Richard M.

A curriculum guide, in outline form, for oceanography field laboratories is presented. Designed to complement and expand upon an oceanography lecture course, it provides a list of objectives related to student experiences in three areas: (1) operating oceanographic equipment; (2) gathering, manipulating, and evaluating data; and (3) writing formal…

Statistical Significance and Effect Size: Two Sides of a Coin.

ERIC Educational Resources Information Center

Fan, Xitao

This paper suggests that statistical significance testing and effect size are two sides of the same coin; they complement each other, but do not substitute for one another. Good research practice requires that both should be taken into consideration to make sound quantitative decisions. A Monte Carlo simulation experiment was conducted, and a…

The Art of Learning: A Guide to Outstanding North Carolina Arts in Education Programs.

ERIC Educational Resources Information Center

Herman, Miriam L.

The Arts in Education programs delineated in this guide complement the rigorous arts curriculum taught by arts specialists in North Carolina schools and enable students to experience the joy of the creative process while reinforcing learning in other curricula: language arts, mathematics, social studies, science, and physical education. Programs…

Outdoor Education in Girl Scouting.

ERIC Educational Resources Information Center

Kennedy, Carolyn L.

This book was written to help Girl Scout leaders prepare themselves and the girls with whom they work to enjoy outdoor experiences together. It complements the age-level handbook and leaders' guide, and training provided by the local Girl Scout council. The book contains nine chapters. The first chapter lists age-level characteristics of girls,…

The Land Is Like a Book.

ERIC Educational Resources Information Center

Andrews, Tom

2002-01-01

A 10-day summer science camp for high school students at an ecological research station in the Canadian tundra combines outdoor education and science education. Experiences with Dene elders led staff to implement their traditional teaching methods using the landscape as teacher. All classes are held outside, and a Dene couple complements the staff…

Beer and Fast Cars: How Brewers Target Blue-collar Youth through Motor Sport Sponsorships.

ERIC Educational Resources Information Center

Buchanan, David R.; Lev, Jane

This study explored how motor sports sponsorships complement and amplify the brewers' media campaigns by joining masculinity, risk, excitement, and beer in the actual "lived" experiences of potential consumers. To document industry expenditures and justifications for motor sports sponsorship, trade journals and newsletters (N=25) and…

Developing Non-Formal Education Competences as a Complement of Formal Education for STEM Lecturers

ERIC Educational Resources Information Center

Terrazas-Marín, Roy Alonso

2018-01-01

This paper focuses on a current practice piece on professional development for university lecturers, transformative learning, dialogism and STEM (Science, Technology, Engineering and Mathematics) education. Its main goals are to identify the key characteristics that allow STEM educators to experiment with the usage of non-formal education…

Measurement of high-voltage and radiation-damage limitations to advanced solar array performance

NASA Technical Reports Server (NTRS)

Guidice, D. A.; Severance, P. S.; Keinhardt, K. C.

1991-01-01

A description is given of the reconfigured Photovoltaic Array Space Power (PASP) Plus experiment: its objectives, solar-array complement, and diagnostic sensors. Results from a successful spaceflight will lead to a better understanding of high-voltage and radiation-damage limitations in the operation of new-technology solar arrays.

Questioning LibQUAL+[TM]: Expanding Its Assessment of Academic Library Effectiveness

ERIC Educational Resources Information Center

Edgar, William B.

2006-01-01

This article examines LibQUAL+[TM]'s instrument, fundamental assumption, and research approach and proposes a functional/technical model of academic library effectiveness. This expanded view of library effectiveness complements LibQUAL+[TM], emphasizing it to be dependent upon users' experience of service delivery, as LibQUAL+[TM] recognizes.…

Is Research Mediating the Relationship between Teaching Experience and Student Satisfaction?

ERIC Educational Resources Information Center

Berbegal-Mirabent, Jasmina; Mas-Machuca, Marta; Marimon, Frederic

2018-01-01

Universities must ensure that academic staff are qualified and competent for performing their job. Teaching and research are two key activities in which lecturers should excel. While some authors suggest teaching and research complement each other and positively influence student satisfaction, some others point to a rivalry effect between the two.…

[How can rehabilitation and the psychiatric sector complement each other?].

PubMed

Dandoy, Stéphanie

2014-01-01

The specific experience of the ESAT in Aubervilliers enables us to measure the benefit which a real partnership between the medico-social team and the area psychiatric team could have. This complementary approach favours a topological separation between a place of support and a place of work and facilitates the individual's personal reconstruction.

Potential synergistic effects of cereal rye biomass and soybean planting density on weed suppression

USDA-ARS?s Scientific Manuscript database

Increasing crop density is a cultural weed management practice that can complement the use of cover crops for weed suppression. In this research, we created a range of cover crop biomass and soybean densities in order to assess their weed suppressive ability alone and in combination. The experiment ...

Academics across Borders: Narratives of Linguistic Capital, Language Competence and Communication Strategies

ERIC Educational Resources Information Center

Gimenez, Julio; Morgan, W. John

2017-01-01

This article reports on a study that examined the personal employment paths of six international academics at a British university. To complement previous accounts of difficult migration, it focuses on the successful experiences of such academics, in particular how proficiency in English facilitated their move into employment in higher education…

Exploring Quarks, Gluons and the Higgs Boson

ERIC Educational Resources Information Center

Johansson, K. Erik

2013-01-01

With real particle collision data available on the web, the amazing dynamics of the fundamental particles of the standard model can be explored in classrooms. Complementing the events from the ATLAS experiment with animations of the fundamental processes on the quark and gluon level makes it possible to better understand the invisible world of…

OTFE, Payload Specialist Fred Leslie works in Spacelab

NASA Image and Video Library

1995-11-05

STS073-233-007 (20 October - 5 November 1995) --- Payload specialist Fred W. Leslie makes use of the versatile U.S. Microgravity Laboratory (USML-2) glovebox to conduct an investigation with the Oscillatory Thermocapillary Flow Experiment (OTFE). This complement of the Surface-Tension-Driven Convection Experiment (STDCE) studies the shapes that fluid surfaces in weightless environments assume within specific containers. Leslie was one of two guest researchers who joined five NASA astronauts for 16 days of on Earth-orbit research in support of USML-2.

Two-Electron Correlations in e+H-->e+e+p Near Threshold

NASA Astrophysics Data System (ADS)

Kato, Daiji; Watanabe, Shinichi

1995-03-01

We present an ab initio calculation of the ionization cross section of atomic hydrogen near threshold with precision that compares excellently with the Shah-Elliot-Gilbody experiment [J. Phys. B 20, 3501 (1987)]. This fills the gap between theory and experiment down to 0.1 a.u. above threshold, complementing the recent spectacular work of Bray and Stelbovics [Phys. Rev. Lett. 70, 746 (1993)]. The angular momentum distributions of the secondary electron display an evolution in correlation patterns toward the threshold.

Invalid corps.

PubMed

Lande, R Gregory

2008-06-01

This article explores America's historical experience with medical disability compensation programs during the Revolutionary War and the Civil War. Contemporary newspaper reports, complemented by book and journal articles, provide an understanding of the medical disability compensation programs offered during the Revolutionary War and the Civil War. Military planners, politicians, and service members struggled to develop a fair and balanced medical disability compensation program during the Revolutionary War and the Civil War. Based on America's extensive experience with the Civil War Invalid Corps, an alternative for motivated military personnel could be developed.

PASP Plus: An experiment to measure space-environment effects on photovoltaic power subsystems

NASA Technical Reports Server (NTRS)

Guidice, Donald A.

1992-01-01

The Photovoltaic Array Space Power Plus Diagnostic experiment (PASP Plus) was accepted as part of the APEX Mission payload aboard a Pegastar satellite to be orbited by a Pegasus launch vehicle in late 1992. The mission's elliptical orbit will allow us to investigate both space plasma and space radiation effects. PASP Plus will have eleven types of solar arrays and a full complement of environmental and interactions diagnostic sensors. Measurements of space-plasma interactions on the various solar arrays will be made at large negative voltages (to investigate arcing parameters) and at large positive voltages (to investigate leakage currents) by biasing the arrays to various levels up to -500 and +500 volts. The long-term deterioration in solar array performance caused by exposure to space radiation will also be investigated; radiation dosage will be measured by an electron/proton dosimeter included in the environmental sensor complement. Experimental results from PASP Plus will help establish cause-and-effect relationships and lead to improved design guidelines and test standards for new-technology solar arrays.

Genetics Home Reference: Fanconi anemia

MedlinePlus

... D1 Genetic Testing Registry: Fanconi anemia, complementation group D2 Genetic Testing Registry: Fanconi anemia, complementation group E ... ANEMIA, COMPLEMENTATION GROUP D1 FANCONI ANEMIA, COMPLEMENTATION GROUP D2 FANCONI ANEMIA, COMPLEMENTATION GROUP E FANCONI ANEMIA, COMPLEMENTATION ...

The 2015 Transition of Wartime Operational Control: A Threat or Opportunity for the ROK /US Alliance

DTIC Science & Technology

2014-06-13

effects in regional stability. In other words, as Matthew J. Jordan pointed out, multilateral efforts will complement and not supplant established...operations. 46Matthew J. Jordan , “Multilateralism in North East Asia” (Master’s Naval War College...dismantling DPRK’s nuclear program. The impetus for these talks emerged in 2003 when the DPRK revealed its uranium enrichment program. This enrichment

Molecular Characterization of Two Lactate Dehydrogenase Genes with a Novel Structural Organization on the Genome of Lactobacillus sp. Strain MONT4

PubMed Central

Weekes, Jennifer; Yüksel, Gülhan Ü.

2004-01-01

Two lactate dehydrogenase (ldh) genes from Lactobacillus sp. strain MONT4 were cloned by complementation in Escherichia coli DC1368 (ldh pfl) and were sequenced. The sequence analysis revealed a novel genomic organization of the ldh genes. Subcloning of the individual ldh genes and their Northern blot analyses indicated that the genes are monocistronic. PMID:15466577

Sequence and molecular characterization of a DNA region encoding the dibenzothiophene desulfurization operon of Rhodococcus sp. strain IGTS8.

PubMed Central

Piddington, C S; Kovacevich, B R; Rambosek, J

1995-01-01

Dibenzothiophene (DBT), a model compound for sulfur-containing organic molecules found in fossil fuels, can be desulfurized to 2-hydroxybiphenyl (2-HBP) by Rhodococcus sp. strain IGTS8. Complementation of a desulfurization (dsz) mutant provided the genes from Rhodococcus sp. strain IGTS8 responsible for desulfurization. A 6.7-kb TaqI fragment cloned in Escherichia coli-Rhodococcus shuttle vector pRR-6 was found to both complement this mutation and confer desulfurization to Rhodococcus fascians, which normally is not able to desulfurize DBT. Expression of this fragment in E. coli also conferred the ability to desulfurize DBT. A molecular analysis of the cloned fragment revealed a single operon containing three open reading frames involved in the conversion of DBT to 2-HBP. The three genes were designated dszA, dszB, and dszC. Neither the nucleotide sequences nor the deduced amino acid sequences of the enzymes exhibited significant similarity to sequences obtained from the GenBank, EMBL, and Swiss-Prot databases, indicating that these enzymes are novel enzymes. Subclone analyses revealed that the gene product of dszC converts DBT directly to DBT-sulfone and that the gene products of dszA and dszB act in concert to convert DBT-sulfone to 2-HBP. PMID:7574582

Gender differences in autoimmunity associated with exposure to environmental factors

PubMed Central

Pollard, K. Michael

2011-01-01

Autoimmunity is thought to result from a combination of genetics, environmental triggers, and stochastic events. Gender is also a significant risk factor with many diseases exhibiting a female bias. Although the role of environmental triggers, especially medications, in eliciting autoimmunity is well established less is known about the interplay between gender, the environment and autoimmunity. This review examines the contribution of gender in autoimmunity induced by selected chemical, physical and biological agents in humans and animal models. Epidemiological studies reveal that environmental factors can be associated with a gender bias in human autoimmunity. However many studies show that the increased risk of autoimmunity is often influenced by occupational exposure or other gender biased activities. Animal studies, although often prejudiced by the exclusive use of female animals, reveal that gender bias can be strain specific suggesting an interaction between sex chromosome complement and background genes. This observation has important implications because it argues that within a gender biased disease there may be individuals in which gender does not contribute to autoimmunity. Exposure to environmental factors, which encompasses everything around us, adds an additional layer of complexity. Understanding how the environment influences the relationship between sex chromosome complement and innate and adaptive immune responses will be essential in determining the role of gender in environmentally-induced autoimmunity. PMID:22137891

The role of hemocytes in A. gambiae antiplasmodial immunity

PubMed Central

Ramirez, Jose Luis; Garver, Lindsey S.; Brayner, Fábio André; Alves, Luiz Carlos; Rodrigues, Janneth; Molina-Cruz, Alvaro; Barillas-Mury, Carolina

2013-01-01

Hemocytes synthesize key components of the mosquito complement-like system, but their role in the activation of antiplasmodial responses has not been established. The effect of activating Toll signaling in hemocytes on Plasmodium survival was investigated by transferring hemocytes or cell-free hemolymph from donor mosquitoes in which the suppressor cactus was silenced. These transfers greatly enhanced antiplasmodial immunity, indicating that hemocytes are active players in the activation of the complement-like system, through an effector(s) regulated by the Toll pathway. A comparative analysis of hemocyte populations between susceptible (S) G3 and the refractory (R) L3-5 A. gambiae mosquito strains did not reveal significant differences under basal conditions or in response to Plasmodium berghei infection. The response of S mosquitoes to different Plasmodium species revealed similar kinetics following infection with P. berghei, P. yoelii or P. falciparum, but the strength of the priming response was stronger in less compatible mosquito-parasite pairs. The Toll, Imd, STAT or JNK signaling cascades were not essential for the production of hemocyte differentiation factor (HDF) in response to P. berghei infection, but disruption of Toll, STAT or JNK abolished hemocyte differentiation in response to HDF. We conclude that hemocytes are key mediators of A. gambiae antiplasmodial responses. PMID:23886925

Knowledge-based design of a biosensor to quantify localized ERK activation in living cells

PubMed Central

Kummer, Lutz; Hsu, Chia-Wen; Dagliyan, Onur; MacNevin, Christopher; Kaufholz, Melanie; Zimmermann, Bastian; Dokholyan, Nikolay V.; Hahn, Klaus M.; Plückthun, Andreas

2014-01-01

Summary Investigation of protein activation in living cells is fundamental to understand how proteins are influenced by the full complement of upstream regulators they experience. We describe here the generation of a biosensor based on the Designed Ankyrin Repeat Protein (DARPin) binding scaffold suited for intracellular applications. Combining selection and evolution from libraries, knowledge-based design and efficient and rapid testing of conjugate candidates, we created an ERK activity biosensor by derivatizing a DARPin specific for phosphorylated ERK (pERK) with a solvatochromic merocyanine dye (mero87), whose fluorescence increases upon pERK binding. The biosensor specifically responded to pERK2, recognized by its conformation, but not to non-phosphorylated ERK2 or other closely related mitogen-activated kinases tested. Activated endogenous ERK was visualized in mouse embryo fibroblasts incubated in 2% serum, revealing greater activation in the nucleus, perinuclear regions, and especially the nucleoli. Activity was greatly reduced by the MEK1/2 inhibitor U0126. The DARPin-based biosensor will serve as useful tool for studying biological functions of ERK in vitro and in vivo. PMID:23790495

Chemical combination effects predict connectivity in biological systems

PubMed Central

Lehár, Joseph; Zimmermann, Grant R; Krueger, Andrew S; Molnar, Raymond A; Ledell, Jebediah T; Heilbut, Adrian M; Short, Glenn F; Giusti, Leanne C; Nolan, Garry P; Magid, Omar A; Lee, Margaret S; Borisy, Alexis A; Stockwell, Brent R; Keith, Curtis T

2007-01-01

Efforts to construct therapeutically useful models of biological systems require large and diverse sets of data on functional connections between their components. Here we show that cellular responses to combinations of chemicals reveal how their biological targets are connected. Simulations of pathways with pairs of inhibitors at varying doses predict distinct response surface shapes that are reproduced in a yeast experiment, with further support from a larger screen using human tumour cells. The response morphology yields detailed connectivity constraints between nearby targets, and synergy profiles across many combinations show relatedness between targets in the whole network. Constraints from chemical combinations complement genetic studies, because they probe different cellular components and can be applied to disease models that are not amenable to mutagenesis. Chemical probes also offer increased flexibility, as they can be continuously dosed, temporally controlled, and readily combined. After extending this initial study to cover a wider range of combination effects and pathway topologies, chemical combinations may be used to refine network models or to identify novel targets. This response surface methodology may even apply to non-biological systems where responses to targeted perturbations can be measured. PMID:17332758

Mapping transcription factor interactome networks using HaloTag protein arrays.

PubMed

Yazaki, Junshi; Galli, Mary; Kim, Alice Y; Nito, Kazumasa; Aleman, Fernando; Chang, Katherine N; Carvunis, Anne-Ruxandra; Quan, Rosa; Nguyen, Hien; Song, Liang; Alvarez, José M; Huang, Shao-Shan Carol; Chen, Huaming; Ramachandran, Niroshan; Altmann, Stefan; Gutiérrez, Rodrigo A; Hill, David E; Schroeder, Julian I; Chory, Joanne; LaBaer, Joshua; Vidal, Marc; Braun, Pascal; Ecker, Joseph R

2016-07-19

Protein microarrays enable investigation of diverse biochemical properties for thousands of proteins in a single experiment, an unparalleled capacity. Using a high-density system called HaloTag nucleic acid programmable protein array (HaloTag-NAPPA), we created high-density protein arrays comprising 12,000 Arabidopsis ORFs. We used these arrays to query protein-protein interactions for a set of 38 transcription factors and transcriptional regulators (TFs) that function in diverse plant hormone regulatory pathways. The resulting transcription factor interactome network, TF-NAPPA, contains thousands of novel interactions. Validation in a benchmarked in vitro pull-down assay revealed that a random subset of TF-NAPPA validated at the same rate of 64% as a positive reference set of literature-curated interactions. Moreover, using a bimolecular fluorescence complementation (BiFC) assay, we confirmed in planta several interactions of biological interest and determined the interaction localizations for seven pairs. The application of HaloTag-NAPPA technology to plant hormone signaling pathways allowed the identification of many novel transcription factor-protein interactions and led to the development of a proteome-wide plant hormone TF interactome network.

Reproducibility of manual pressure force on provocation of the sacroiliac joint.

PubMed

Levin, U; Nilsson-Wikmar, L; Stenström, C H; Lundeberg, T

1998-01-01

Previous studies of pain-provocation sacroiliac (SI) joint tests have revealed conflicting results. The aim of the present study was to evaluate the intra- and inter-test reliability of pressure force applied during distraction test, compression test and pressure on the apex sacralis. Seventeen physiotherapists (PTs), median age 43 years and median clinical experience 11 years, all experienced in musculoskeletal evaluation and therapy, participated in the study. Each PT performed each test on the same healthy volunteer for 20 s, on three separate occasions, at intervals of one week using a specially constructed examination table which registered pressure force. The PTs were capable of maintaining a relatively constant pressure force for 20 s. The intra-test reliability was acceptable even though there were individual differences on different occasions between those PTs who used the SI joint tests often and those who seldom or never used them. The inter-test reliability was insufficient. The findings indicate the advantage of registering pressure force as a complement for standardized methods for pain-provoking tests and when learning provocation tests, since individual variability was considerable.

Implicit Learning of Predictive Relationships in Three-element Visual Sequences by Young and Old Adults

PubMed Central

Howard, James H.; Howard, Darlene V.; Dennis, Nancy A.; Kelly, Andrew J.

2008-01-01

Knowledge of sequential relationships enables future events to be anticipated and processed efficiently. Research with the serial reaction time task (SRTT) has shown that sequence learning often occurs implicitly without effort or awareness. Here we report four experiments that use a triplet-learning task (TLT) to investigate sequence learning in young and older adults. In the TLT people respond only to the last target event in a series of discrete, three-event sequences or triplets. Target predictability is manipulated by varying the triplet frequency (joint probability) and/or the statistical relationships (conditional probabilities) among events within the triplets. Results revealed that both groups learned, though older adults showed less learning of both joint and conditional probabilities. Young people used the statistical information in both cues, but older adults relied primarily on information in the second cue alone. We conclude that the TLT complements and extends the SRTT and other tasks by offering flexibility in the kinds of sequential statistical regularities that may be studied as well as by controlling event timing and eliminating motor response sequencing. PMID:18763897

Affective norms of 875 Spanish words for five discrete emotional categories and two emotional dimensions.

PubMed

Hinojosa, J A; Martínez-García, N; Villalba-García, C; Fernández-Folgueiras, U; Sánchez-Carmona, A; Pozo, M A; Montoro, P R

2016-03-01

In the present study, we introduce affective norms for a new set of Spanish words, the Madrid Affective Database for Spanish (MADS), that were scored on two emotional dimensions (valence and arousal) and on five discrete emotional categories (happiness, anger, sadness, fear, and disgust), as well as on concreteness, by 660 Spanish native speakers. Measures of several objective psycholinguistic variables--grammatical class, word frequency, number of letters, and number of syllables--for the words are also included. We observed high split-half reliabilities for every emotional variable and a strong quadratic relationship between valence and arousal. Additional analyses revealed several associations between the affective dimensions and discrete emotions, as well as with some psycholinguistic variables. This new corpus complements and extends prior databases in Spanish and allows for designing new experiments investigating the influence of affective content in language processing under both dimensional and discrete theoretical conceptions of emotion. These norms can be downloaded as supplemental materials for this article from www.dropbox.com/s/o6dpw3irk6utfhy/Hinojosa%20et%20al_Supplementary%20materials.xlsx?dl=0 .

Development and preliminary evaluation of a new test of ongoing speech comprehension.

PubMed

Best, Virginia; Keidser, Gitte; Buchholz, Jӧrg M; Freeston, Katrina

2016-01-01

The overall goal of this work is to create new speech perception tests that more closely resemble real world communication and offer an alternative or complement to the commonly used sentence recall test. We describe the development of a new ongoing speech comprehension test based on short everyday passages and on-the-go questions. We also describe the results of an experiment conducted to compare the psychometric properties of this test to those of a sentence test. Both tests were completed by a group of listeners that included normal hearers as well as hearing-impaired listeners who participated with and without their hearing aids. Overall, the psychometric properties of the two tests were similar, and thresholds were significantly correlated. However, there was some evidence of age/cognitive effects in the comprehension test that were not revealed by the sentence test. This new comprehension test promises to be useful for the larger goal of creating laboratory tests that combine realistic acoustic environments with realistic communication tasks. Further efforts will be required to assess whether the test can ultimately improve predictions of real-world outcomes.

The Identification of Two Arabinosyltransferases from Tomato Reveals Functional Equivalency of Xyloglucan Side Chain Substituents1[W][OPEN

PubMed Central

Schultink, Alex; Cheng, Kun; Park, Yong Bum; Cosgrove, Daniel J.; Pauly, Markus

2013-01-01

Xyloglucan (XyG) is the dominant hemicellulose present in the primary cell walls of dicotyledonous plants. Unlike Arabidopsis (Arabidopsis thaliana) XyG, which contains galactosyl and fucosyl substituents, tomato (Solanum lycopersicum) XyG contains arabinofuranosyl residues. To investigate the biological function of these differing substituents, we used a functional complementation approach. Candidate glycosyltransferases were identified from tomato by using comparative genomics with known XyG galactosyltransferase genes from Arabidopsis. These candidate genes were expressed in an Arabidopsis mutant lacking XyG galactosylation, and two of them resulted in the production of arabinosylated XyG, a structure not previously found in this plant species. These genes may therefore encode XyG arabinofuranosyltransferases. Moreover, the addition of arabinofuranosyl residues to the XyG of this Arabidopsis mutant rescued a growth and cell wall biomechanics phenotype, demonstrating that the function of XyG in plant growth, development, and mechanics has considerable flexibility in terms of the specific residues in the side chains. These experiments also highlight the potential of reengineering the sugar substituents on plant wall polysaccharides without compromising growth or viability. PMID:23893172

Sequestration by IFIT1 Impairs Translation of 2′O-unmethylated Capped RNA

PubMed Central

Lacerda, Livia; Benda, Christian; Holze, Cathleen; Eberl, Christian H.; Mann, Angelika; Kindler, Eveline; Gil-Cruz, Cristina; Ziebuhr, John; Thiel, Volker; Pichlmair, Andreas

2013-01-01

Viruses that generate capped RNA lacking 2′O methylation on the first ribose are severely affected by the antiviral activity of Type I interferons. We used proteome-wide affinity purification coupled to mass spectrometry to identify human and mouse proteins specifically binding to capped RNA with different methylation states. This analysis, complemented with functional validation experiments, revealed that IFIT1 is the sole interferon-induced protein displaying higher affinity for unmethylated than for methylated capped RNA. IFIT1 tethers a species-specific protein complex consisting of other IFITs to RNA. Pulsed stable isotope labelling with amino acids in cell culture coupled to mass spectrometry as well as in vitro competition assays indicate that IFIT1 sequesters 2′O-unmethylated capped RNA and thereby impairs binding of eukaryotic translation initiation factors to 2′O-unmethylated RNA template, which results in inhibition of translation. The specificity of IFIT1 for 2′O-unmethylated RNA serves as potent antiviral mechanism against viruses lacking 2′O-methyltransferase activity and at the same time allows unperturbed progression of the antiviral program in infected cells. PMID:24098121

Leveraging algal omics to reveal potential targets for augmenting TAG accumulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arora, Neha; Pienkos, Philip T.; Pruthi, Vikas

Ongoing global efforts to commercialize microalgal biofuels have expedited the use of multi-omics techniques to gain insights into lipid biosynthetic pathways. Functional genomics analyses have recently been employed to complement existing sequence-level omics studies, shedding light on the dynamics of lipid synthesis and its interplay with other cellular metabolic pathways, thus revealing possible targets for metabolic engineering. Here, we review the current status of algal omics studies to reveal potential targets to augment TAG accumulation in various microalgae. Here, this review specifically aims to examine and catalog systems level data related to stress-induced TAG accumulation in oleaginous microalgae and informmore » future metabolic engineering strategies to develop strains with enhanced bioproductivity, which could pave a path for sustainable green energy.« less

Leveraging Algal Omics to Reveal Potential Targets for Augmenting TAG Accumulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guarnieri, Michael T; Pienkos, Philip T; Arora, Neha

2018-04-18

Ongoing global efforts to commercialize microalgal biofuels have expedited the use of multi-omics techniques to gain insights into lipid biosynthetic pathways. Functional genomics analyses have recently been employed to complement existing sequence-level omics studies, shedding light on the dynamics of lipid synthesis and its interplay with other cellular metabolic pathways, thus revealing possible targets for metabolic engineering. Here, we review the current status of algal omics studies to reveal potential targets to augment TAG accumulation in various microalgae. This review specifically aims to examine and catalog systems level data related to stress-induced TAG accumulation in oleaginous microalgae and inform futuremore » metabolic engineering strategies to develop strains with enhanced bioproductivity, which could pave a path for sustainable green energy.« less

Leveraging algal omics to reveal potential targets for augmenting TAG accumulation

DOE PAGES

Arora, Neha; Pienkos, Philip T.; Pruthi, Vikas; ...

2018-04-18

Ongoing global efforts to commercialize microalgal biofuels have expedited the use of multi-omics techniques to gain insights into lipid biosynthetic pathways. Functional genomics analyses have recently been employed to complement existing sequence-level omics studies, shedding light on the dynamics of lipid synthesis and its interplay with other cellular metabolic pathways, thus revealing possible targets for metabolic engineering. Here, we review the current status of algal omics studies to reveal potential targets to augment TAG accumulation in various microalgae. Here, this review specifically aims to examine and catalog systems level data related to stress-induced TAG accumulation in oleaginous microalgae and informmore » future metabolic engineering strategies to develop strains with enhanced bioproductivity, which could pave a path for sustainable green energy.« less

Leveraging algal omics to reveal potential targets for augmenting TAG accumulation.

PubMed

Arora, Neha; Pienkos, Philip T; Pruthi, Vikas; Poluri, Krishna Mohan; Guarnieri, Michael T

2018-04-18

Ongoing global efforts to commercialize microalgal biofuels have expedited the use of multi-omics techniques to gain insights into lipid biosynthetic pathways. Functional genomics analyses have recently been employed to complement existing sequence-level omics studies, shedding light on the dynamics of lipid synthesis and its interplay with other cellular metabolic pathways, thus revealing possible targets for metabolic engineering. Here, we review the current status of algal omics studies to reveal potential targets to augment TAG accumulation in various microalgae. This review specifically aims to examine and catalog systems level data related to stress-induced TAG accumulation in oleaginous microalgae and inform future metabolic engineering strategies to develop strains with enhanced bioproductivity, which could pave a path for sustainable green energy. Copyright © 2018. Published by Elsevier Inc.

The role of language in the development of false belief understanding: a training study.

PubMed

Lohmann, Heidemarie; Tomasello, Michael

2003-01-01

The current study used a training methodology to determine whether different kinds of linguistic interaction play a causal role in children's development of false belief understanding. After 3 training sessions, 3-year-old children improved their false belief understanding both in a training condition involving perspective-shifting discourse about deceptive objects (without mental state terms) and in a condition in which sentential complement syntax was used (without deceptive objects). Children did not improve in a condition in which they were exposed to deceptive objects without accompanying language. Children showed most improvement in a condition using both perspective-shifting discourse and sentential complement syntax, suggesting that each of these types of linguistic experience plays an independent role in the ontogeny of false belief understanding.

A Distributed Middleware Architecture for Attack-Resilient Communications in Smart Grids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hodge, Brian S; Wu, Yifu; Wei, Jin

Distributed Energy Resources (DERs) are being increasingly accepted as an excellent complement to traditional energy sources in smart grids. As most of these generators are geographically dispersed, dedicated communications investments for every generator are capital cost prohibitive. Real-time distributed communications middleware, which supervises, organizes and schedules tremendous amounts of data traffic in smart grids with high penetrations of DERs, allows for the use of existing network infrastructure. In this paper, we propose a distributed attack-resilient middleware architecture that detects and mitigates the congestion attacks by exploiting the Quality of Experience (QoE) measures to complement the conventional Quality of Service (QoS)more » information to detect and mitigate the congestion attacks effectively. The simulation results illustrate the efficiency of our proposed communications middleware architecture.« less

A Distributed Middleware Architecture for Attack-Resilient Communications in Smart Grids: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Yifu; Wei, Jin; Hodge, Bri-Mathias

Distributed energy resources (DERs) are being increasingly accepted as an excellent complement to traditional energy sources in smart grids. Because most of these generators are geographically dispersed, dedicated communications investments for every generator are capital-cost prohibitive. Real-time distributed communications middleware - which supervises, organizes, and schedules tremendous amounts of data traffic in smart grids with high penetrations of DERs - allows for the use of existing network infrastructure. In this paper, we propose a distributed attack-resilient middleware architecture that detects and mitigates the congestion attacks by exploiting the quality of experience measures to complement the conventional quality of service informationmore » to effectively detect and mitigate congestion attacks. The simulation results illustrate the efficiency of our proposed communications middleware architecture.« less

A perspective of computational fluid dynamics

NASA Technical Reports Server (NTRS)

Kutler, P.

1986-01-01

Computational fluid dynamics (CFD) is maturing, and is at a stage in its technological life cycle in which it is now routinely applied to some rather complicated problems; it is starting to create an impact on the design cycle of aerospace flight vehicles and their components. CFD is also being used to better understand the fluid physics of flows heretofore not understood, such as three-dimensional separation. CFD is also being used to complement and is being complemented by experiments. In this paper, the primary and secondary pacing items that govern CFD in the past are reviewed and updated. The future prospects of CFD are explored which will offer people working in the discipline challenges that should extend the technological life cycle to further increase the capabilities of a proven demonstrated technology.

Synergy between the classical and alternative pathways of complement is essential for conferring effective protection against the pandemic influenza A(H1N1) 2009 virus infection

PubMed Central

Rattan, Ajitanuj; Pawar, Shailesh D.; Nawadkar, Renuka; Kulkarni, Neeraja

2017-01-01

The pandemic influenza A(H1N1) 2009 virus caused significant morbidity and mortality worldwide thus necessitating the need to understand the host factors that influence its control. Previously, the complement system has been shown to provide protection during the seasonal influenza virus infection, however, the role of individual complement pathways is not yet clear. Here, we have dissected the role of intact complement as well as of its individual activation pathways during the pandemic influenza virus infection using mouse strains deficient in various complement components. We show that the virus infection in C3-/- mice results in increased viral load and 100% mortality, which can be reversed by adoptive transfer of naïve wild-type (WT) splenocytes, purified splenic B cells, or passive transfer of immune sera from WT, but not C3-/- mice. Blocking of C3a and/or C5a receptor signaling in WT mice using receptor antagonists and use of C3aR-/- and C5aR-/- mice showed significant mortality after blocking/ablation of C3aR, with little or no effect after blocking/ablation of C5aR. Intriguingly, deficiency of C4 and FB in mice resulted in only partial mortality (24%-32%) suggesting a necessary cross-talk between the classical/lectin and alternative pathways for providing effective protection. In vitro virus neutralization experiments performed to probe the cross-talk between the various pathways indicated that activation of the classical and alternative pathways in concert, owing to coating of viral surface by antibodies, is needed for its efficient neutralization. Examination of the virus-specific complement-binding antibodies in virus positive subjects showed that their levels vary among individuals. Together these results indicate that cooperation between the classical and alternative pathways not only result in efficient direct neutralization of the pandemic influenza virus, but also lead to the optimum generation of C3a, which when sensed by the immune cells along with the antigen culminates in generation of effective protective immune responses. PMID:28301559

Guinea pig complement potently measures vibriocidal activity of human antibodies in response to cholera vaccines.

PubMed

Kim, Kyoung Whun; Jeong, Soyoung; Ahn, Ki Bum; Yang, Jae Seung; Yun, Cheol-Heui; Han, Seung Hyun

2017-12-01

The vibriocidal assay using guinea pig complement is widely used for the evaluation of immune responses to cholera vaccines in human clinical trials. However, it is unclear why guinea pig complement has been used over human complement in the measurement of vibriocidal activity of human sera and there have not been comparison studies for the use of guinea pig complement over those from other species. Therefore, we comparatively investigated the effects of complements derived from human, guinea pig, rabbit, and sheep on vibriocidal activity. Complements from guinea pig, rabbit, and human showed concentration-dependent vibriocidal activity in the presence of quality control serum antibodies. Of these complements, guinea pig complement was the most sensitive and effective over a wide concentration range. When the vibriocidal activity of complements was measured in the absence of serum antibodies, human, sheep, and guinea pig complements showed vibriocidal activity up to 40-fold, 20-fold, and 1-fold dilution, respectively. For human pre- and post-vaccination sera, the most potent vibriocidal activity was observed when guinea pig complement was used. In addition, the highest fold-increases between pre- and post- vaccinated sera were obtained with guinea pig complement. Furthermore, human complement contained a higher amount of V. cholerae- and its lipopolysaccharide-specific antibodies than guinea pig complement. Collectively, these results suggest that guinea pig complements are suitable for vibriocidal assays due to their high sensitivity and effectiveness to human sera.

Searching for long-lived particles: A compact detector for exotics at LHCb

NASA Astrophysics Data System (ADS)

Gligorov, Vladimir V.; Knapen, Simon; Papucci, Michele; Robinson, Dean J.

2018-01-01

We advocate for the construction of a new detector element at the LHCb experiment, designed to search for displaced decays of beyond Standard Model long-lived particles, taking advantage of a large shielded space in the LHCb cavern that is expected to soon become available. We discuss the general features and putative capabilities of such an experiment, as well as its various advantages and complementarities with respect to the existing LHC experiments and proposals such as SHiP and MATHUSLA. For two well-motivated beyond Standard Model benchmark scenarios—Higgs decay to dark photons and B meson decays via a Higgs mixing portal—the reach either complements or exceeds that predicted for other LHC experiments.

The Autophagy Gene BcATG8 Regulates the Vegetative Differentiation and Pathogenicity of Botrytis cinerea.

PubMed

Ren, Weichao; Liu, Na; Sang, Chengwei; Shi, Dongya; Zhou, Mingguo; Chen, Changjun; Qin, Qingming; Chen, Wenchan

2018-06-01

Autophagy is a conserved degradation process that maintains intracellular homeostasis to ensure normal cell differentiation and development in eukaryotes. ATG8 is one of the key molecular components of the autophagy pathway. In this study, we identified and characterized BcATG8 , a homologue of Saccharomyces cerevisiae (yeast) ATG8 in the necrotrophic plant pathogen Botrytis cinerea Yeast complementation experiments demonstrated that BcATG8 can functionally complement the defects of the yeast ATG8 null mutant. Direct physical interaction between BcAtg8 and BcAtg4 was detected in the yeast two-hybrid system. Subcellular localization assays showed that green fluorescent protein-tagged BcAtg8 (GFP-BcAtg8) localized in the cytoplasm as preautophagosomal structures (PAS) under general conditions but mainly accumulated in the lumen of vacuoles in the case of autophagy induction. Deletion of BcATG8 (Δ BcAtg8 mutant) blocked autophagy and significantly impaired mycelial growth, conidiation, sclerotial formation, and virulence. In addition, the conidia of the Δ BcAtg8 mutant contained fewer lipid droplets (LDs), and quantitative real-time PCR (qRT-PCR) assays revealed that the basal expression levels of the LD metabolism-related genes in the mutant were significantly different from those in the wild-type (WT) strain. All of these phenotypic defects were restored by gene complementation. These results indicate that BcATG8 is essential for autophagy to regulate fungal development, pathogenesis, and lipid metabolism in B. cinerea IMPORTANCE The gray mold fungus Botrytis cinerea is an economically important plant pathogen with a broad host range. Although there are fungicides for its control, many classes of fungicides have failed due to its genetic plasticity. Exploring the fundamental biology of B. cinerea can provide the theoretical basis for sustainable and long-term disease management. Autophagy is an intracellular process for degradation and recycling of cytosolic materials in eukaryotes and is now known to be vital for fungal life. Here, we report studies of the biological role of the autophagy gene BcATG8 in B. cinerea The results suggest that autophagy plays a crucial role in vegetative differentiation and virulence of B. cinerea . Copyright © 2018 American Society for Microbiology.

Deep phenotyping of 89 xeroderma pigmentosum patients reveals unexpected heterogeneity dependent on the precise molecular defect

PubMed Central

Fassihi, Hiva; Sethi, Mieran; Fawcett, Heather; Wing, Jonathan; Chandler, Natalie; Mohammed, Shehla; Craythorne, Emma; Morley, Ana M. S.; Lim, Rongxuan; Turner, Sally; Henshaw, Tanya; Garrood, Isabel; Giunti, Paola; Hedderly, Tammy; Abiona, Adesoji; Naik, Harsha; Harrop, Gemma; McGibbon, David; Jaspers, Nicolaas G. J.; Botta, Elena; Nardo, Tiziana; Stefanini, Miria; Young, Antony R.; Sarkany, Robert P. E.; Lehmann, Alan R.

2016-01-01

Xeroderma pigmentosum (XP) is a rare DNA repair disorder characterized by increased susceptibility to UV radiation (UVR)-induced skin pigmentation, skin cancers, ocular surface disease, and, in some patients, sunburn and neurological degeneration. Genetically, it is assigned to eight complementation groups (XP-A to -G and variant). For the last 5 y, the UK national multidisciplinary XP service has provided follow-up for 89 XP patients, representing most of the XP patients in the United Kingdom. Causative mutations, DNA repair levels, and more than 60 clinical variables relating to dermatology, ophthalmology, and neurology have been measured, using scoring systems to categorize disease severity. This deep phenotyping has revealed unanticipated heterogeneity of clinical features, between and within complementation groups. Skin cancer is most common in XP-C, XP-E, and XP-V patients, previously considered to be the milder groups based on cellular analyses. These patients have normal sunburn reactions and are therefore diagnosed later and are less likely to adhere to UVR protection. XP-C patients are specifically hypersensitive to ocular damage, and XP-F and XP-G patients appear to be much less susceptible to skin cancer than other XP groups. Within XP groups, different mutations confer susceptibility or resistance to neurological damage. Our findings on this large cohort of XP patients under long-term follow-up reveal that XP is more heterogeneous than has previously been appreciated. Our data now enable provision of personalized prognostic information and management advice for each XP patient, as well as providing new insights into the functions of the XP proteins. PMID:26884178

KSC-03PD-0089

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. - A student shows off one of the experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03PD-0085

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. - Students pause during their work on their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03PD-0093

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. -- Students show off one of the experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03PD-0092

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. -- Students show off one of the experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0093

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. -- Students show off one of the experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0089

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. - A student shows off one of the experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0092

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. -- Students show off one of the experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

KSC-03pd0085

NASA Image and Video Library

2003-01-15

KENNEDY SPACE CENTER, FLA. - Students pause during their work on their experiments that will fly in SPACEHAB on Space Shuttle Columbia on mission STS-107. SPACEHAB's complement of commercial experiments includes six educational experiments designed and developed by students in six different countries under the auspices of Space Technology and Research Students (STARS), a global education program managed by SPACEHAB subsidiary Space Media. The countries represented are Australia, China, Israel, Japan, Liechtenstein and the United States. The student investigators who conceived these experiments will monitor their operations in space. The experiments will be housed in BioServe Space Technologies' Isothermal Containment Module (ICM --a small temperature-controlled facility that provides experiment support such as physical containment, lighting, and video imaging) and stowed in a middeck-size locker aboard the SPACEHAB Research Double Module.

Mathematical and computational approaches can complement experimental studies of host-pathogen interactions.

PubMed

Kirschner, Denise E; Linderman, Jennifer J

2009-04-01

In addition to traditional and novel experimental approaches to study host-pathogen interactions, mathematical and computer modelling have recently been applied to address open questions in this area. These modelling tools not only offer an additional avenue for exploring disease dynamics at multiple biological scales, but also complement and extend knowledge gained via experimental tools. In this review, we outline four examples where modelling has complemented current experimental techniques in a way that can or has already pushed our knowledge of host-pathogen dynamics forward. Two of the modelling approaches presented go hand in hand with articles in this issue exploring fluorescence resonance energy transfer and two-photon intravital microscopy. Two others explore virtual or 'in silico' deletion and depletion as well as a new method to understand and guide studies in genetic epidemiology. In each of these examples, the complementary nature of modelling and experiment is discussed. We further note that multi-scale modelling may allow us to integrate information across length (molecular, cellular, tissue, organism, population) and time (e.g. seconds to lifetimes). In sum, when combined, these compatible approaches offer new opportunities for understanding host-pathogen interactions.

Organics Exposure in Orbit (OREOcube): A Next-Generation Space Exposure Platform

NASA Technical Reports Server (NTRS)

Elsaesser, Andreas; Quinn, Richard; Ehrenfreund, Pascale; Mattioda, Andrew L.; Ricco, Antonio J.; Alonzo, Jason; Breitenbach, Alex; Chan, Yee Kim; Fresneau, Aurelien; Salama, Farid;

The quasi-harmonic ultrasonic polar scan for material characterization: experiment and numerical modeling.

PubMed

Kersemans, Mathias; Martens, Arvid; Van Den Abeele, Koen; Degrieck, Joris; Pyl, Lincy; Zastavnik, Filip; Sol, Hugo; Van Paepegem, Wim

2015-04-01

Conventionally, the ultrasonic polar scan (UPS) records the amplitude or time-of-flight in transmission using short ultrasonic pulses for a wide range of incidence angles, resulting in a fingerprint of the critical bulk wave angles of the material at the insonified spot. Here, we investigate the use of quasi-harmonic ultrasound (bursts) in a polar scan experiment, both experimentally and numerically. It is shown that the nature of the fingerprint drastically changes, and reveals the positions of the leaky Lamb angles. To compare with experiments, both plane wave and bounded beam simulations have been performed based on the recursive stiffness matrix method. Whereas the plane wave computations yield a pure Lamb wave angle fingerprint, this is no longer valid for the more realistic case of a bounded beam. The experimental recordings are fully supported by the bounded beam simulations. To complement the traditional amplitude measurement, experimental and numerical investigations have been performed to record, predict and analyze the phase of the transmitted ultrasonic beam. This results in the conceptual introduction of the 'phase polar scan', exposing even more intriguing and detailed patterns. In fact, the combination of the amplitude and the phase polar scan provides the complete knowledge about the complex transmission coefficient for every possible angle of incidence. This comprehensive information will be very valuable for inverse modeling of the local elasticity tensor based on a single UPS experiment. Finally, the UPS method has been applied for the detection of an artificial delamination. Compared to the pulsed UPS, the quasi-harmonic UPS (both the amplitude and phase recording) shows a superior sensitivity to the presence of a delamination. Copyright © 2015 Elsevier B.V. All rights reserved.

The Complement System in Dialysis: A Forgotten Story?

PubMed Central

Poppelaars, Felix; Faria, Bernardo; Gaya da Costa, Mariana; Franssen, Casper F. M.; van Son, Willem J.; Berger, Stefan P.; Daha, Mohamed R.; Seelen, Marc A.

2018-01-01

Significant advances have lead to a greater understanding of the role of the complement system within nephrology. The success of the first clinically approved complement inhibitor has created renewed appreciation of complement-targeting therapeutics. Several clinical trials are currently underway to evaluate the therapeutic potential of complement inhibition in renal diseases and kidney transplantation. Although, complement has been known to be activated during dialysis for over four decades, this area of research has been neglected in recent years. Despite significant progress in biocompatibility of hemodialysis (HD) membranes and peritoneal dialysis (PD) fluids, complement activation remains an undesired effect and relevant issue. Short-term effects of complement activation include promoting inflammation and coagulation. In addition, long-term complications of dialysis, such as infection, fibrosis and cardiovascular events, are linked to the complement system. These results suggest that interventions targeting the complement system in dialysis could improve biocompatibility, dialysis efficacy, and long-term outcome. Combined with the clinical availability to safely target complement in patients, the question is not if we should inhibit complement in dialysis, but when and how. The purpose of this review is to summarize previous findings and provide a comprehensive overview of the role of the complement system in both HD and PD. PMID:29422906

DOE Office of Scientific and Technical Information (OSTI.GOV)

McGee, Mike; Harms, Elvin; Klebaner, Arkadiy

Two TESLA-style 8-cavity cryomodules have been operated at Fermilab Accelerator Science and Technology (FAST), formerly the Superconducting Radio Frequency (SRF) Accelerator Test Facility. Operational instabilities were revealed during Radio Frequency (RF) power studies. These observations were complemented by the characterization of thermal acoustic effects on cavity microphonics manifested by apparent noisy boiling of helium involving vapor bubble and liquid vibration. The thermal acoustic measurements also consider pressure and temperature spikes which drive the phenomenon at low and high frequencies.

CSI Web Adventures: A Forensics Virtual Apprenticeship for Teaching Science and Inspiring STEM Careers

ERIC Educational Resources Information Center

Miller, Leslie; Chang, Ching-I; Hoyt, Daniel

2010-01-01

CSI: The Experience, a traveling museum exhibit and a companion web adventure, was created through a grant from the National Science Foundation as a potential model for informal learning. The website was designed to enrich and complement the exhibit by modeling the forensic process. Substantive science, real-world lab techniques, and higher-level…

Empirical Analysis of the Use of the VISIR Remote Lab in Teaching Analog Electronics

ERIC Educational Resources Information Center

Garcia-Zubia, Javier; Cuadros, Jordi; Romero, Susana; Hernandez-Jayo, Unai; Orduña, Pablo; Guenaga, Mariluz; Gonzalez-Sabate, Lucinio; Gustavsson, Ingvar

2017-01-01

Remote laboratories give students the opportunity of experimenting in STEM by using the Internet to control and measure an experimental setting. Remote laboratories are increasingly used in the classroom to complement, or substitute for, hands-on laboratories, so it is important to know its learning value. While many authors approach this question…

Mapping Civic Engagement: A Case Study of Service-Learning in Appalachia

ERIC Educational Resources Information Center

Mann, Jessica; Casebeer, Daniel

2016-01-01

This study uses social cartography to map student perceptions of a co-curricular service-learning project in an impoverished rural community. As a complement to narrative discourse, mapping provides an opportunity to visualize not only the spatial nature of the educational experience but also, in this case, the benefits of civic engagement. The…

Rhythmic Alternation and the Optional Complementiser in English: New Evidence of Phonological Influence on Grammatical Encoding

ERIC Educational Resources Information Center

Lee, Ming-Wei; Gibbons, Julie

2007-01-01

In a recall-based spoken production experiment, native English-speaking participants' variable use of the complementiser "that" to introduce the sentential complement in sentences like "Henry knew (that) Lucy/Louise washed the dishes" was found to be related to whether "that" inclusion/omission resulted in an alternating sequence of stressed and…

How Artefacts Mediate Small-Group Co-Creation Activities in a Mobile-Assisted Seamless Language Learning Environment?

ERIC Educational Resources Information Center

Wong, L. -H.; Chen, W.; Jan, M.

2012-01-01

The rich learning resources and contexts learners experience in their everyday life could play important roles in complementing formal learning, but are often neglected by learners and teachers. In this paper, we present an intervention study in "Move, Idioms!", a mobile-assisted Chinese language learning approach that emphasizes contextualized…

Learning About Life the Playful Way: From Kindergarten to Play Group. Situation Report.

ERIC Educational Resources Information Center

Kischke, Martina I.

This paper describes various types of child care services available for preschool children in West Germany. The paper emphasizes the importance of play in children's cognitive and social development. Preschool experiences guided by a trained staff are considered an important complement to family life. According to the paper, West Germany is…

iVirtualWorld: A Domain-Oriented End-User Development Environment for Building 3D Virtual Chemistry Experiments

ERIC Educational Resources Information Center

Zhong, Ying

2013-01-01

Virtual worlds are well-suited for building virtual laboratories for educational purposes to complement hands-on physical laboratories. However, educators may face technical challenges because developing virtual worlds requires skills in programming and 3D design. Current virtual world building tools are developed for users who have programming…

Making the Invisible Visible: Enhancing Students' Conceptual Understanding by Introducing Representations of Abstract Objects in a Simulation

ERIC Educational Resources Information Center

Olympiou, Georgios; Zacharias, Zacharia; deJong, Ton

2013-01-01

This study aimed to identify if complementing representations of concrete objects with representations of abstract objects improves students' conceptual understanding as they use a simulation to experiment in the domain of "Light and Color". Moreover, we investigated whether students' prior knowledge is a factor that must be considered in deciding…

Task Experience and Children's Working Memory Performance: A Perspective from Recall Timing

ERIC Educational Resources Information Center

Towse, John N.; Cowan, Nelson; Horton, Neil J.; Whytock, Shealagh

2008-01-01

Working memory is an important theoretical construct among children, and measures of its capacity predict a range of cognitive skills and abilities. Data from 9- and 11-year-old children illustrate how a chronometric analysis of recall can complement and elaborate recall accuracy in advancing our understanding of working memory. A reading span…

Optical design for the Laser Astrometric Test of Relativity

NASA Technical Reports Server (NTRS)

Turyshev, Slava G.; Shao, Michael; Nordtvedt, Kenneth L., Jr.

2004-01-01

This paper discusses the Laser Astrometric Test of Relativity (LATOR) mission. LATOR is a Michelson-Morley-type experiment designed to test the pure tensor metric nature of gravitation the fundamental postulate of Einstein's theory of general relativity. With its focus on gravity's action on light propagation it complements other tests which rely on the gravitational dynamics of bodies.

Designing Mixed Reality Mobile Games for Crisis Management Training

ERIC Educational Resources Information Center

Di Loreto, Ines; Mora, Simone; Divitini, Monica

2013-01-01

Games for crisis management offer an interesting complement to traditional training. Experiments on their usage show that games can be promising tools able to address some of the limitations of traditional training. Also our first assessment with a board game for panic management shows that this particular kind of game could be useful for soft…

Using Mobile Phones to Prepare for University Lectures: Student's Experiences

ERIC Educational Resources Information Center

Rismark, Marit; Solvberg, Astrid M.; Stromme, Alex; Hokstad, Leif Martin

2007-01-01

In this paper we present findings from a study of students' use of mobile phones in a biology course at the Norwegian University of Science and Technology (NTNU). Using a qualitative research approach we focus on how mobile phones can complement and add value to the educational challenge of encouraging university students to obtain some topic…

Structural study of the Fox-1 RRM protein hydration reveals a role for key water molecules in RRM-RNA recognition

PubMed Central

Blatter, Markus; Cléry, Antoine; Damberger, Fred F.

2017-01-01

Abstract The Fox-1 RNA recognition motif (RRM) domain is an important member of the RRM protein family. We report a 1.8 Å X-ray structure of the free Fox-1 containing six distinct monomers. We use this and the nuclear magnetic resonance (NMR) structure of the Fox-1 protein/RNA complex for molecular dynamics (MD) analyses of the structured hydration. The individual monomers of the X-ray structure show diverse hydration patterns, however, MD excellently reproduces the most occupied hydration sites. Simulations of the protein/RNA complex show hydration consistent with the isolated protein complemented by hydration sites specific to the protein/RNA interface. MD predicts intricate hydration sites with water-binding times extending up to hundreds of nanoseconds. We characterize two of them using NMR spectroscopy, RNA binding with switchSENSE and free-energy calculations of mutant proteins. Both hydration sites are experimentally confirmed and their abolishment reduces the binding free-energy. A quantitative agreement between theory and experiment is achieved for the S155A substitution but not for the S122A mutant. The S155 hydration site is evolutionarily conserved within the RRM domains. In conclusion, MD is an effective tool for predicting and interpreting the hydration patterns of protein/RNA complexes. Hydration is not easily detectable in NMR experiments but can affect stability of protein/RNA complexes. PMID:28505313

Complement Activation in Inflammatory Skin Diseases

PubMed Central

Giang, Jenny; Seelen, Marc A. J.; van Doorn, Martijn B. A.; Rissmann, Robert; Prens, Errol P.; Damman, Jeffrey

2018-01-01

The complement system is a fundamental part of the innate immune system, playing a crucial role in host defense against various pathogens, such as bacteria, viruses, and fungi. Activation of complement results in production of several molecules mediating chemotaxis, opsonization, and mast cell degranulation, which can contribute to the elimination of pathogenic organisms and inflammation. Furthermore, the complement system also has regulating properties in inflammatory and immune responses. Complement activity in diseases is rather complex and may involve both aberrant expression of complement and genetic deficiencies of complement components or regulators. The skin represents an active immune organ with complex interactions between cellular components and various mediators. Complement involvement has been associated with several skin diseases, such as psoriasis, lupus erythematosus, cutaneous vasculitis, urticaria, and bullous dermatoses. Several triggers including auto-antibodies and micro-organisms can activate complement, while on the other hand complement deficiencies can contribute to impaired immune complex clearance, leading to disease. This review provides an overview of the role of complement in inflammatory skin diseases and discusses complement factors as potential new targets for therapeutic intervention. PMID:29713318

On the intracellular trafficking of mouse S5 ribosomal protein from cytoplasm to nucleoli.

PubMed

Matragkou, Ch; Papachristou, H; Karetsou, Z; Papadopoulos, G; Papamarcaki, T; Vizirianakis, I S; Tsiftsoglou, A S; Choli-Papadopoulou, T

2009-10-09

The non-ribosomal functions of mammalian ribosomal proteins have recently attracted worldwide attention. The mouse ribosomal protein S5 (rpS5) derived from ribosomal material is an assembled non-phosphorylated protein. The free form of rpS5 protein, however, undergoes phosphorylation. In this study, we have (a) investigated the potential role of phosphorylation in rpS5 protein transport into the nucleus and then into nucleoli and (b) determined which of the domains of rpS5 are involved in this intracellular trafficking. In vitro PCR mutagenesis of mouse rpS5 cDNA, complemented by subsequent cloning and expression of rpS5 truncated recombinant forms, produced in fusion with green fluorescent protein, permitted the investigation of rpS5 intracellular trafficking in HeLa cells using confocal microscopy complemented by Western blot analysis. Our results indicate the following: (a) rpS5 protein enters the nucleus via the region 38-50 aa that forms a random coil as revealed by molecular dynamic simulation. (b) Immunoprecipitation of rpS5 with casein kinase II and immobilized metal affinity chromatography analysis complemented by in vitro kinase assay revealed that phosphorylation of rpS5 seems to be indispensable for its transport from nucleus to nucleoli; upon entering the nucleus, Thr-133 phosphorylation triggers Ser-24 phosphorylation by casein kinase II, thus promoting entrance of rpS5 into the nucleoli. Another important role of rpS5 N-terminal region is proposed to be the regulation of protein's cellular level. The repetitively co-appearance of a satellite C-terminal band below the entire rpS5 at the late stationary phase, and not at the early logarithmic phase, of cell growth suggests a specific degradation balancing probably the unassembled ribosomal protein molecules with those that are efficiently assembled to ribosomal subunits. Overall, these data provide new insights on the structural and functional domains within the rpS5 molecule that contribute to its cellular functions.

MHC-matched induced pluripotent stem cells can attenuate cellular and humoral immune responses but are still susceptible to innate immunity in pigs.

PubMed

Mizukami, Yoshihisa; Abe, Tomoyuki; Shibata, Hiroaki; Makimura, Yukitoshi; Fujishiro, Shuh-hei; Yanase, Kimihide; Hishikawa, Shuji; Kobayashi, Eiji; Hanazono, Yutaka

2014-01-01

Recent studies have revealed negligible immunogenicity of induced pluripotent stem (iPS) cells in syngeneic mice and in autologous monkeys. Therefore, human iPS cells would not elicit immune responses in the autologous setting. However, given that human leukocyte antigen (HLA)-matched allogeneic iPS cells would likely be used for medical applications, a more faithful model system is needed to reflect HLA-matched allogeneic settings. Here we examined whether iPS cells induce immune responses in the swine leukocyte antigen (SLA)-matched setting. iPS cells were generated from the SLA-defined C1 strain of Clawn miniature swine, which were confirmed to develop teratomas in mice, and transplanted into the testes (n = 4) and ovary (n = 1) of C1 pigs. No teratomas were found in pigs on 47 to 125 days after transplantation. A Mixed lymphocyte reaction revealed that T-cell responses to the transplanted MHC-matched (C1) iPS cells were significantly lower compared to allogeneic cells. The humoral immune responses were also attenuated in the C1-to-C1 setting. More importantly, even MHC-matched iPS cells were susceptible to innate immunity, NK cells and serum complement. iPS cells lacked the expression of SLA class I and sialic acids. The in vitro cytotoxic assay showed that C1 iPS cells were targeted by NK cells and serum complement of C1. In vivo, the C1 iPS cells developed larger teratomas in NK-deficient NOG (T-B-NK-) mice (n = 10) than in NK-competent NOD/SCID (T-B-NK+) mice (n = 8) (p<0.01). In addition, C1 iPS cell failed to form teratomas after incubation with the porcine complement-active serum. Taken together, MHC-matched iPS cells can attenuate cellular and humoral immune responses, but still susceptible to innate immunity in pigs.

Identification of Plasmodium falciparum DNA Repair Protein Mre11 with an Evolutionarily Conserved Nuclease Function

PubMed Central

Badugu, Sugith Babu; Nabi, Shaik Abdul; Vaidyam, Pratap; Laskar, Shyamasree; Bhattacharyya, Sunanda; Bhattacharyya, Mrinal Kanti

2015-01-01

The eukaryotic Meiotic Recombination protein 11 (Mre11) plays pivotal roles in the DNA damage response (DDR). Specifically, Mre11 senses and signals DNA double strand breaks (DSB) and facilitates their repair through effector proteins belonging to either homologous recombination (HR) or non-homologous end joining (NHEJ) repair mechanisms. In the human malaria parasite Plasmodium falciparum, HR and alternative-NHEJ have been identified; however, little is known about the upstream factors involved in the DDR of this organism. In this report, we identify a putative ortholog of Mre11 in P. falciparum (PfalMre11) that shares 22% sequence similarity to human Mre11. Homology modeling reveals striking structural resemblance of the predicted PfalMre11 nuclease domain to the nuclease domain of Saccharomyces cerevisiae Mre11 (ScMre11). Complementation analyses reveal functional conservation of PfalMre11 nuclease activity as demonstrated by the ability of the PfalMre11 nuclease domain, in conjunction with the C-terminal domain of ScMre11, to functionally complement an mre11 deficient yeast strain. Functional complementation was virtually abrogated by an amino acid substitution in the PfalMre11 nuclease domain (D398N). PfalMre11 is abundant in the mitotically active trophozoite and schizont stages of P. falciparum and is up-regulated in response to DNA damage, suggesting a role in the DDR. PfalMre11 exhibits physical interaction with PfalRad50. In addition, yeast 2-hybrid studies show that PfalMre11 interacts with ScRad50 and ScXrs2, two important components of the well characterized Mre11-Rad50-Xrs2 complex which is involved in DDR signaling and repair in S. cerevisiae, further supporting a role for PfalMre11 in the DDR. Taken together, these findings provide evidence that PfalMre11 is an evolutionarily conserved component of the DDR in Plasmodium. PMID:25938776

The Combined Release and Radiation Effects Satellite program (CRRES): A unique series of scientific experiments

NASA Technical Reports Server (NTRS)

1991-01-01

CRRES is a program to study the space environment which surrounds Earth and the effects of space radiation on modern satellite electronic systems. The satellite will carry an array of active experiments including chemical releases and a complement of sophisticated scientific instruments to accomplish these objectives. Other chemical release active experiments will be performed with suborbital rocket probes. These chemical releases will paint the magnetic and electric fields in Earthspace with clouds of glowing ions. Earthspace will be a laboratory, and the releases will be studied with an extensive network of ground-, aircraft-, and satellite-based diagnostic instruments.

KSC-97PC947

NASA Image and Video Library

1997-06-28

STS-94 Pilot Susan Leigh Still arrives at the Shuttle Landing Facility aboard a T-38 jet in preparation for the reflight of the Microgravity Science Laboratory-1 mission. Launch is scheduled for July 1, 1997, at 2:37 p.m. EDT. The laboratory was scheduled to fly again with the full complement of STS-83 experiments after that mission was cut short due to a faulty fuel cell. During the scheduled 16-day STS-94 mission, the experiments will be used to test some of the hardware, facilities and procedures that are planned for use on the International Space Station while the flight crew conducts combustion, protein crystal growth and materials processing experiments

KSC-97PC946

NASA Image and Video Library

1997-06-28

STS-94 Commander James D. Halsell, Jr., arrives at the Shuttle Landing Facility aboard a T-38 jet in preparation for the reflight of the Microgravity Science Laboratory-1 mission. Launch is scheduled for July 1, 1997, at 2:37 p.m. EDT. The laboratory was scheduled to fly again with the full complement of STS-83 experiments after that mission was cut short due to a faulty fuel cell. During the scheduled 16-day STS-94 mission, the experiments will be used to test some of the hardware, facilities and procedures that are planned for use on the International Space Station while the flight crew conducts combustion, protein crystal growth and materials processing experiments

Laboratory experiments in integrated circuit fabrication

NASA Technical Reports Server (NTRS)

Jenkins, Thomas J.; Kolesar, Edward S.

1993-01-01

The objectives of the experiment are fourfold: to provide practical experience implementing the fundamental processes and technology associated with the science and art of integrated circuit (IC) fabrication; to afford the opportunity for the student to apply the theory associated with IC fabrication and semiconductor device operation; to motivate the student to exercise engineering decisions associated with fabricating integrated circuits; and to complement the theory of n-channel MOS and diffused devices that are presented in the classroom by actually fabricating and testing them. Therefore, a balance between theory and practice can be realized in the education of young engineers, whose education is often criticized as lacking sufficient design and practical content.

The Semantics of Complementation in English: A Cognitive Semantic Account of Two English Complement Constructions

ERIC Educational Resources Information Center

Smith, Michael B.

2009-01-01

Studies on complementation in English and other languages have traditionally focused on syntactic issues, most notably on the constituent structures of different complement types. As a result, they have neglected the role of meaning in the choice of different complements. This paper investigates the semantics of complementation within the…

Pressure dependence of carbonate exchange with [NpO 2(CO 3) 3] 4– in aqueous solutions

DOE PAGES

Pilgrim, Corey D.; Zavarin, Mavrik; Casey, William H.

2016-12-13

Here, the rates of ligand exchange into the geochemically important [NpO 2(CO 3) 3] 4– aqueous complex are measured as a function of pressure in order to complement existing data on the isostructural [UO 2(CO 3) 3] 4– complex. Experiments are conducted at pH conditions where the rate of exchange is independent of the proton concentration. Unexpectedly, the experiments show a distinct difference in the pressure dependencies of rates of exchange for the uranyl and neptunyl complexes.

The Complement System and Adverse Pregnancy Outcomes

PubMed Central

Regal, Jean F.; Gilbert, Jeffrey S.; Burwick, Richard M.

2015-01-01

Adverse pregnancy outcomes significantly contribute to morbidity and mortality for mother and child, with lifelong health consequences for both. The innate and adaptive immune system must be regulated to insure survival of the feta allograft, and the complement system is no exception. An intact complement system optimizes placental development and function and is essential to maintain host defense and fetal survival. Complement regulation is apparent at the placental interface from early pregnancy with some degree of complement activation occurring normally throughout gestation. However, a number of pregnancy complications including early pregnancy loss, fetal growth restriction, hypertensive disorders of pregnancy and preterm birth are associated with excessive or misdirected complement activation, and are more frequent in women with inherited or acquired complement system disorders or complement gene mutations. Clinical studies employing complement biomarkers in plasma and urine implicate dysregulated complement activation in components of each of the adverse pregnancy outcomes. In addition, mechanistic studies in rat and mouse models of adverse pregnancy outcomes address the complement pathways or activation products of importance and allow critical analysis of the pathophysiology. Targeted complement therapeutics are already in use to control adverse pregnancy outcomes in select situations. A clearer understanding of the role of the complement system in both normal pregnancy and complicated or failed pregnancy will allow a rational approach to future therapeutic strategies for manipulating complement with the goal of mitigating adverse pregnancy outcomes, preserving host defense, and improving long term outcomes for both mother and child. PMID:25802092

Remote collection and analysis of witness reports on flash floods

NASA Astrophysics Data System (ADS)

Gourley, Jonathan; Erlingis, Jessica; Smith, Travis; Ortega, Kiel; Hong, Yang

2010-05-01

Typically, flash floods are studied ex post facto in response to a major impact event. A complement to field investigations is developing a detailed database of flash flood events, including minor events and null reports (i.e., where heavy rain occurred but there was no flash flooding), based on public survey questions conducted in near-real time. The Severe Hazards Analysis and Verification Experiment (SHAVE) has been in operation at the National Severe Storms Laboratory (NSSL) in Norman, OK, USA during the summers since 2006. The experiment employs undergraduate students to analyse real-time products from weather radars, target specific regions within the conterminous US, and poll public residences and businesses regarding the occurrence and severity of hail, wind, tornadoes, and now flash floods. In addition to providing a rich learning experience for students, SHAVE has been successful in creating high-resolution datasets of severe hazards used for algorithm and model verification. This talk describes the criteria used to initiate the flash flood survey, the specific questions asked and information entered to the database, and then provides an analysis of results for flash flood data collected during the summer of 2008. It is envisioned that specific details provided by the SHAVE flash flood observation database will complement databases collected by operational agencies and thus lead to better tools to predict the likelihood of flash floods and ultimately reduce their impacts on society.

Laboratory Experiments on Meandering Meltwater Channels

NASA Astrophysics Data System (ADS)

Fernandez, R.; Berens, J.; Parker, G.; Stark, C. P.

2017-12-01

Meandering channels of all scales and flowing over a wide variety of media have common planform patterns. Although the analogy in planform suggests there is a common underlying framework, the constitutive relations driving planform evolution through vertical incision/deposition and lateral migration differ from medium to medium. The driving processes in alluvial and mixed bedrock-alluvial meandering channels have been studied substantially over the last decades. However, this is not the case for meandering channels in other media such as ice or soluble rock. Here we present results from experiments conducted at the Ven Te Chow Hydrosystems Laboratory of the University of Illinois at Urbana-Champaign on meltwater meandering channels. A rivulet is carved into an ice block and water is allowed to flow at a constant discharge. Planform evolution is analyzed with time lapse imaging and complemented with rubber molds of the channel once the experiment is over. These molds give us the full 3D structure of the meandering, including incisional overhang. Vertical incision rates are measured throughout the run by taking elevations along the channel, and these measurements are complemented with analysis from the molds. We show examples of meandering of intense amplitude with deep overhangs. Features resembling scroll bars document cyclically punctuated melting. We report on lateral migration rates, incision rates, sinuosity, channel depths, channel widths, reach averaged velocities, bend wavelengths and amplitudes and compare them to values reported in the literature for alluvial rivers.

Spacecraft attitude determination accuracy from mission experience

NASA Technical Reports Server (NTRS)

Brasoveanu, D.; Hashmall, J.

1994-01-01

This paper summarizes a compilation of attitude determination accuracies attained by a number of satellites supported by the Goddard Space Flight Center Flight Dynamics Facility. The compilation is designed to assist future mission planners in choosing and placing attitude hardware and selecting the attitude determination algorithms needed to achieve given accuracy requirements. The major goal of the compilation is to indicate realistic accuracies achievable using a given sensor complement based on mission experience. It is expected that the use of actual spacecraft experience will make the study especially useful for mission design. A general description of factors influencing spacecraft attitude accuracy is presented. These factors include determination algorithms, inertial reference unit characteristics, and error sources that can affect measurement accuracy. Possible techniques for mitigating errors are also included. Brief mission descriptions are presented with the attitude accuracies attained, grouped by the sensor pairs used in attitude determination. The accuracies for inactive missions represent a compendium of missions report results, and those for active missions represent measurements of attitude residuals. Both three-axis and spin stabilized missions are included. Special emphasis is given to high-accuracy sensor pairs, such as two fixed-head star trackers (FHST's) and fine Sun sensor plus FHST. Brief descriptions of sensor design and mode of operation are included. Also included are brief mission descriptions and plots summarizing the attitude accuracy attained using various sensor complements.

Characterization of the Bacillus stearothermophilus manganese superoxide dismutase gene and its ability to complement copper/zinc superoxide dismutase deficiency in Saccharomyces cerevisiae

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bowler, C.; Inze, D.; Van Camp, W.

1990-03-01

Recombinant clones containing the manganese superoxide dismutase (MnSOD) gene of Bacillus stearothermophilus were isolated with an oligonucleotide probe designed to match a part of the previously determined amino acid sequence. Complementation analyses, performed by introducing each plasmid into a superoxide dismutase-deficient mutant of Escherichia coli, allowed us to define the region of DNA which encodes the MnSOD structural gene and to identify a promoter region immediately upstream from the gene. These data were subsequently confirmed by DNA sequencing. Since MnSOD is normally restricted to the mitochondria in eucaryotes, we were interested (i) in determining whether B. stearothermophilus MnSOD could functionmore » in eucaryotic cytosol and (ii) in determining whether MnSOD could replace the structurally unrelated copper/zinc superoxide dismutase (Cu/ZnSOD) which is normally found there. To test this, the sequence encoding bacterial MnSOD was cloned into a yeast expression vector and subsequently introduced into a Cu/ZnSOD-deficient mutant of the yeast Saccharomyces cerevisiae. Functional expression of the protein was demonstrated, and complementation tests revealed that the protein was able to provide tolerance at wild-type levels to conditions which are normally restrictive for this mutant. Thus, in spite of the evolutionary unrelatedness of these two enzymes, Cu/ZnSOD can be functionally replaced by MnSOD in yeast cytosol.« less

Hiding in plain sight: immune evasion by the staphylococcal protein SdrE.

PubMed

Herr, Andrew B; Thorman, Alexander W

2017-05-10

The human immune system is responsible for identification and destruction of invader cells, such as the bacterial pathogen Staphylococcus aureus In response, S. aureus brings to the fight a large number of virulence factors, including several that allow it to evade the host immune response. The staphylococcal surface protein SdrE was recently reported to bind to complement Factor H, an important regulator of complement activation. Factor H attaches to the surface of host cells to inhibit complement activation and amplification, preventing the destruction of the host cell. SdrE binding to Factor H allows S. aureus to mimic a host cell and reduces bacterial killing by granulocytes. In a new study published in Biochemical Journal , Zhang et al. describe crystal structures of SdrE and its complex with the C-terminal portion of Factor H. The structure of SdrE and its interaction with the Factor H peptide closely resemble a family of surface proteins that recognize extracellular matrix components such as fibrinogen. However, unbound SdrE forms a novel 'Closed' conformation with an occluded peptide-binding groove. These structures reveal a fascinating mechanism for immune evasion and provide a potential avenue for the development of novel antimicrobial agents to target SdrE. © 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

Do Archaea and bacteria co-infection have a role in the pathogenesis of chronic chagasic cardiopathy?

PubMed

Higuchi, Maria de Lourdes; Kawakami, Joyce; Ikegami, Renata; Clementino, Maysa Beatriz Mandetta; Kawamoto, Flavio M; Reis, Marcia M; Bocchi, Edimar

2009-07-01

Chronic cardiopathy (CC) in Chagas disease is a fibrotic myocarditis with C5b-9 complement deposition. Mycoplasma and Chlamydia may interfere with the complement response. Proteolytic enzymes and archaeal genes that have been described in Trypanosoma cruzi may increase its virulence. Here we tested the hypothesis that different ratios of Mycoplasma, Chlamydia and archaeal organisms, which are frequent symbionts, may be associated with chagasic clinical forms. eight indeterminate form (IF) and 20 CC chagasic endomyocardial biopsies were submitted to in situ hybridization, electron and immunoelectron microscopy and PCR techniques for detection of Mycoplasma pneumoniae (MP), Chlamydia pneumoniae(CP), C5b-9 and archaeal-like bodies. MP and CP-DNA were always present at lower levels in CC than in IF (p < 0.001) and were correlated with each other only in CC. Electron microscopy revealed Mycoplasma, Chlamydia and two types of archaeal-like bodies. One had electron dense lipid content (EDL) and was mainly present in IF. The other had electron lucent content (ELC) and was mainly present in CC. In this group, ELC correlated negatively with the other microbes and EDL and positively with C5b-9. The CC group was positive for Archaea and T. cruzi DNA. In conclusion, different amounts of Mycoplasma, Chlamydia and archaeal organisms may be implicated in complement activation and may have a role in Chagas disease outcome.

Mutant Cells That Do Not Respond to Interleukin-1 (IL-1) Reveal a Novel Role for IL-1 Receptor-Associated Kinase

PubMed Central

Li, Xiaoxia; Commane, Mairead; Burns, Carmel; Vithalani, Kalpa; Cao, Zhaodan; Stark, George R.

1999-01-01

Mutagenized human 293 cells containing an interleukin-1 (IL-1)-regulated herpes thymidine kinase gene, selected in IL-1 and gancyclovir, have yielded many independent clones that are unresponsive to IL-1. The four clones analyzed here carry recessive mutations and represent three complementation groups. Mutant A in complementation group I1 lacks IL-1 receptor-associated kinase (IRAK), while the mutants in the other two groups are defective in unknown components that function upstream of IRAK. Expression of exogenous IRAK in I1A cells (I1A-IRAK) restores their responsiveness to IL-1. Neither NFκB nor Jun kinase is activated in IL-1-treated I1A cells, but these responses are restored in I1A-IRAK cells, indicating that IRAK is required for both. To address the role of the kinase activity of IRAK in IL-1 signaling, its ATP binding site was mutated (K239A), completely abolishing kinase activity. In transfected I1A cells, IRAK-K239A was still phosphorylated upon IL-1 stimulation and, surprisingly, still complemented all the defects in the mutant cells. Therefore, IRAK must be phosphorylated by a different kinase, and phospho-IRAK must play a role in IL-1-mediated signaling that does not require its kinase activity. PMID:10373513

Sundanese Complementation

ERIC Educational Resources Information Center

Kurniawan, Eri

2013-01-01

The focus of this thesis is the description and analysis of clausal complementation in Sundanese, an Austronesian language spoken in Indonesia. The thesis examined a range of clausal complement types in Sundanese, which consists of (i) "yen/(wi)rehna" "that" complements, (ii) "pikeun" "for" complements,…

Contrasting Complement Control, Temporal Adjunct Control and Controlled Verbal Gerund Subjects in ASD: The Role of Contextual Cues in Reference Assignment.

PubMed

Janke, Vikki; Perovic, Alexandra

2017-01-01

This study examines two complex syntactic dependencies (complement control and sentence-final temporal adjunct control) and one pragmatic dependency (controlled verbal gerund subjects) in children with ASD. Sixteen high-functioning (HFA) children (aged 6-16) with a diagnosis of autism and no language impairment, matched on age, gender and non-verbal MA to one TD control group, and on age, gender and verbal MA to another TD control group, undertook three picture-selection tasks. Task 1 measured their base-line interpretations of the empty categories ( ec ). Task 2 preceded these sentence sets with a weakly established topic cueing an alternative referent and Task 3 with a strongly established topic cueing an alternative referent. In complement control (Ron persuaded Hermione ec to kick the ball) and sentence-final temporal adjunct control (Harry tapped Luna while ec feeding the owl), the reference of the ec is argued to be related obligatorily to the object and subject respectively. In controlled verbal-gerund subjects (VGS) ( ec Rowing the boat clumsily made Luna seasick), the ec 's reference is resolved pragmatically. Referent choices across the three tasks were compared. TD children chose the object uniformly in complement control across all tasks but in adjunct control, preferences shifted toward the object in Task 3. In controlled VGSs, they exhibited a strong preference for an internal-referent interpretation in Task 1, which shifted in the direction of the cues in Tasks 2 and 3. HFA children gave a mixed performance. They patterned with their TD counterparts on complement control and controlled VGSs but performed marginally differently on adjunct control: no TD groups were influenced by the weakly established topic in Task 2 but all groups were influenced by the strongly established topic in Task 3. HFA children were less influenced than the TD children, resulting in their making fewer object choices overall but revealing parallel patterns of performance. In this first study of three sub-types of control in ASD, we demonstrate that HFA children consult the same pragmatic cues to the same degree as TD children, in spite of the diverse pragmatic deficits reported for this population.

Contrasting Complement Control, Temporal Adjunct Control and Controlled Verbal Gerund Subjects in ASD: The Role of Contextual Cues in Reference Assignment

PubMed Central

Janke, Vikki; Perovic, Alexandra

2017-01-01

This study examines two complex syntactic dependencies (complement control and sentence-final temporal adjunct control) and one pragmatic dependency (controlled verbal gerund subjects) in children with ASD. Sixteen high-functioning (HFA) children (aged 6–16) with a diagnosis of autism and no language impairment, matched on age, gender and non-verbal MA to one TD control group, and on age, gender and verbal MA to another TD control group, undertook three picture-selection tasks. Task 1 measured their base-line interpretations of the empty categories (ec). Task 2 preceded these sentence sets with a weakly established topic cueing an alternative referent and Task 3 with a strongly established topic cueing an alternative referent. In complement control (Ron persuaded Hermione ec to kick the ball) and sentence-final temporal adjunct control (Harry tapped Luna while ec feeding the owl), the reference of the ec is argued to be related obligatorily to the object and subject respectively. In controlled verbal-gerund subjects (VGS) (ec Rowing the boat clumsily made Luna seasick), the ec's reference is resolved pragmatically. Referent choices across the three tasks were compared. TD children chose the object uniformly in complement control across all tasks but in adjunct control, preferences shifted toward the object in Task 3. In controlled VGSs, they exhibited a strong preference for an internal-referent interpretation in Task 1, which shifted in the direction of the cues in Tasks 2 and 3. HFA children gave a mixed performance. They patterned with their TD counterparts on complement control and controlled VGSs but performed marginally differently on adjunct control: no TD groups were influenced by the weakly established topic in Task 2 but all groups were influenced by the strongly established topic in Task 3. HFA children were less influenced than the TD children, resulting in their making fewer object choices overall but revealing parallel patterns of performance. In this first study of three sub-types of control in ASD, we demonstrate that HFA children consult the same pragmatic cues to the same degree as TD children, in spite of the diverse pragmatic deficits reported for this population. PMID:28400743

Disease-linked mutations in factor H reveal pivotal role of cofactor activity in self-surface-selective regulation of complement activation.

PubMed

Kerr, Heather; Wong, Edwin; Makou, Elisavet; Yang, Yi; Marchbank, Kevin; Kavanagh, David; Richards, Anna; Herbert, Andrew P; Barlow, Paul N

2017-08-11

Spontaneous activation enables the complement system to respond very rapidly to diverse threats. This activation is efficiently suppressed by complement factor H (CFH) on self-surfaces but not on foreign surfaces. The surface selectivity of CFH, a soluble protein containing 20 complement-control protein modules (CCPs 1-20), may be compromised by disease-linked mutations. However, which of the several functions of CFH drives this self-surface selectivity remains unknown. To address this, we expressed human CFH mutants in Pichia pastoris We found that recombinant I62-CFH (protective against age-related macular degeneration) and V62-CFH functioned equivalently, matching or outperforming plasma-derived CFH, whereas R53H-CFH, linked to atypical hemolytic uremic syndrome (aHUS), was defective in C3bBb decay-accelerating activity (DAA) and factor I cofactor activity (CA). The aHUS-linked CCP 19 mutant D1119G-CFH had virtually no CA on (self-like) sheep erythrocytes ( E S ) but retained DAA. The aHUS-linked CCP 20 mutant S1191L/V1197A-CFH (LA-CFH) had dramatically reduced CA on E S but was less compromised in DAA. D1119G-CFH and LA-CFH both performed poorly at preventing complement-mediated hemolysis of E S PspCN, a CFH-binding Streptococcus pneumoniae protein domain, binds CFH tightly and increases accessibility of CCPs 19 and 20. PspCN did not improve the DAA of any CFH variant on E S Conversely, PspCN boosted the CA, on E S , of I62-CFH, R53H-CFH, and LA-CFH and also enhanced hemolysis protection by I62-CFH and LA-CFH. We conclude that CCPs 19 and 20 are critical for efficient CA on self-surfaces but less important for DAA. Exposing CCPs 19 and 20 with PspCN and thus enhancing CA on self-surfaces may reverse deficiencies of some CFH variants. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Complement Evasion Strategies of Viruses: An Overview

PubMed Central

Agrawal, Palak; Nawadkar, Renuka; Ojha, Hina; Kumar, Jitendra; Sahu, Arvind

2017-01-01

Being a major first line of immune defense, the complement system keeps a constant vigil against viruses. Its ability to recognize large panoply of viruses and virus-infected cells, and trigger the effector pathways, results in neutralization of viruses and killing of the infected cells. This selection pressure exerted by complement on viruses has made them evolve a multitude of countermeasures. These include targeting the recognition molecules for the avoidance of detection, targeting key enzymes and complexes of the complement pathways like C3 convertases and C5b-9 formation – either by encoding complement regulators or by recruiting membrane-bound and soluble host complement regulators, cleaving complement proteins by encoding protease, and inhibiting the synthesis of complement proteins. Additionally, viruses also exploit the complement system for their own benefit. For example, they use complement receptors as well as membrane regulators for cellular entry as well as their spread. Here, we provide an overview on the complement subversion mechanisms adopted by the members of various viral families including Poxviridae, Herpesviridae, Adenoviridae, Flaviviridae, Retroviridae, Picornaviridae, Astroviridae, Togaviridae, Orthomyxoviridae and Paramyxoviridae. PMID:28670306

Elucidation of the Block to Herpes Simplex Virus Egress in the Absence of Tegument Protein UL16 Reveals a Novel Interaction with VP22

PubMed Central

Starkey, Jason L.; Han, Jun; Chadha, Pooja; Marsh, Jacob A.

2014-01-01

UL16 is a tegument protein of herpes simplex virus (HSV) that is conserved among all members of the Herpesviridae, but its function is poorly understood. Previous studies revealed that UL16 is associated with capsids in the cytoplasm and interacts with the membrane protein UL11, which suggested a “bridging” function during cytoplasmic envelopment, but this conjecture has not been tested. To gain further insight, cells infected with UL16-null mutants were examined by electron microscopy. No defects in the transport of capsids to cytoplasmic membranes were observed, but the wrapping of capsids with membranes was delayed. Moreover, clusters of cytoplasmic capsids were often observed, but only near membranes, where they were wrapped to produce multiple capsids within a single envelope. Normal virion production was restored when UL16 was expressed either by complementing cells or from a novel position in the HSV genome. When the composition of the UL16-null viruses was analyzed, a reduction in the packaging of glycoprotein E (gE) was observed, which was not surprising, since it has been reported that UL16 interacts with this glycoprotein. However, levels of the tegument protein VP22 were also dramatically reduced in virions, even though this gE-binding protein has been shown not to depend on its membrane partner for packaging. Cotransfection experiments revealed that UL16 and VP22 can interact in the absence of other viral proteins. These results extend the UL16 interaction network beyond its previously identified binding partners to include VP22 and provide evidence that UL16 plays an important function at the membrane during virion production. PMID:24131716

The Pathway Coexpression Network: Revealing pathway relationships

PubMed Central

Tanzi, Rudolph E.

2018-01-01

A goal of genomics is to understand the relationships between biological processes. Pathways contribute to functional interplay within biological processes through complex but poorly understood interactions. However, limited functional references for global pathway relationships exist. Pathways from databases such as KEGG and Reactome provide discrete annotations of biological processes. Their relationships are currently either inferred from gene set enrichment within specific experiments, or by simple overlap, linking pathway annotations that have genes in common. Here, we provide a unifying interpretation of functional interaction between pathways by systematically quantifying coexpression between 1,330 canonical pathways from the Molecular Signatures Database (MSigDB) to establish the Pathway Coexpression Network (PCxN). We estimated the correlation between canonical pathways valid in a broad context using a curated collection of 3,207 microarrays from 72 normal human tissues. PCxN accounts for shared genes between annotations to estimate significant correlations between pathways with related functions rather than with similar annotations. We demonstrate that PCxN provides novel insight into mechanisms of complex diseases using an Alzheimer’s Disease (AD) case study. PCxN retrieved pathways significantly correlated with an expert curated AD gene list. These pathways have known associations with AD and were significantly enriched for genes independently associated with AD. As a further step, we show how PCxN complements the results of gene set enrichment methods by revealing relationships between enriched pathways, and by identifying additional highly correlated pathways. PCxN revealed that correlated pathways from an AD expression profiling study include functional clusters involved in cell adhesion and oxidative stress. PCxN provides expanded connections to pathways from the extracellular matrix. PCxN provides a powerful new framework for interrogation of global pathway relationships. Comprehensive exploration of PCxN can be performed at http://pcxn.org/. PMID:29554099

BINDING OF SOLUBLE IMMUNE COMPLEXES TO HUMAN LYMPHOBLASTOID CELLS

PubMed Central

Theofilopoulos, Argyrios N.; Dixon, Frank J.; Bokisch, Viktor A.

1974-01-01

In the present work we studied the expression of membrane-bound Ig (MBIg) as well as receptors for IgG Fc and complement on nine human lymphoblastoid cell lines. When MBIg and receptors for IgG Fc were compared, four categories of cell lines could be distinguished: (a) cell lines having both MBIg and receptors for IgG Fc, (b) cell lines having MBIg but lacking receptors for IgG Fc, (c) cell lines lacking MBIg but having receptors for IgG Fc, and (d) cell lines lacking both MBIg and receptors for IgG Fc. Two types of receptors for complement could be detected on the cell lines studied, one for C3-C3b and one for C3d. When sensitized red cells carrying C3b or C3d were used for rosette tests, three categories of cell lines could be distinguished: (a) cell lines having receptors for C3b and C3d, (b) cell lines having receptors only for C3d and (c) cell lines lacking both receptors. However, when a more sensitive immunofluorescent method was used instead of the rosette technique, it was found that cell lines unable to form rosettes with EAC1423bhu were able to bind soluble C3 or C3b which indicated the presence of these receptors on the cell surface. Inhibition experiments showed that receptors for C3-C3b and receptors for C3d are distinct and that receptors for C3-C3b and C3d are different from receptors for IgG Fc. A cell line (Raji) without MBIg but with receptors for IgG Fc, C3-C3b, and C3d was selected for use in studying the binding mechanism of soluble immune complexes to cell surface membrane. Aggregated human gamma globulin was used in place of immune complexes. Immune complexes containing complement bind to Raji cells only via receptors for complement, namely receptors for C3-C3b and C3d. Binding of immune complexes containing complement to cells is much greater than that of complexes without complement. Immune complexes bound to cells via receptors for complement can be partially released from the cell surface by addition of normal human serum as well as isolated human C3 or C3b. We postulate that such release is due to competition of immune complex bound C3b and free C3 or C3b for the receptors on Raji cells. PMID:4139225

[Biologically active compounds from the aqueous extract of Urtica dioica].

PubMed

Wagner, H; Willer, F; Kreher, B

1989-10-01

From the water extract of the roots of Urtica dioica (stinging nettle) a polysaccharide fraction was isolated which revealed activity in the carrageenan rat paw edema model and lymphocyte transformation test. Ion exchange chromatography and gel filtration of this fraction afforded 4 different polysaccharides, one of which reduced dose dependent hemolysis in the classical pathway of the complement test. The Urtica dioica lectin (UDA) was reisolated and found to stimulate the proliferation of human lymphocytes.

Combined analysis of transcriptome and proteome data as a tool for the identification of candidate biomarkers in renal cell carcinoma

PubMed Central

Seliger, Barbara; Dressler, Sven P.; Wang, Ena; Kellner, Roland; Recktenwald, Christian V.; Lottspeich, Friedrich; Marincola, Francesco M.; Baumgärtner, Maja; Atkins, Derek; Lichtenfels, Rudolf

2012-01-01

Results obtained from expression profilings of renal cell carcinoma using different “ome”-based approaches and comprehensive data analysis demonstrated that proteome-based technologies and cDNA microarray analyses complement each other during the discovery phase for disease-related candidate biomarkers. The integration of the respective data revealed the uniqueness and complementarities of the different technologies. While comparative cDNA microarray analyses though restricted to upregulated targets largely revealed genes involved in controlling gene/protein expression (19%) and signal transduction processes (13%), proteomics/PROTEOMEX-defined candidate biomarkers include enzymes of the cellular metabolism (36%), transport proteins (12%) and cell motility/structural molecules (10%). Candidate biomarkers defined by proteomics and PROTEOMEX are frequently shared, whereas the sharing rate between cDNA microarray and proteome-based profilings is limited. Putative candidate biomarkers provide insights into their cellular (dys)function and their diagnostic/prognostic value but still warrant further validation in larger patient numbers. Based on the fact that merely 3 candidate biomarkers were shared by all applied technologies, namely annexin A4, tubulin alpha-1A chain and ubiquitin carboxyl-terminal hydrolase L1 the analysis at a single hierarchical level of biological regulation seems to provide only limited results thus emphasizing the importance and benefit of performing rather combinatorial screenings which can complement the standard clinical predictors. PMID:19235166

A Drosophila SNAP-25 null mutant reveals context-dependent redundancy with SNAP-24 in neurotransmission.

PubMed Central

Vilinsky, Ilya; Stewart, Bryan A; Drummond, James; Robinson, Iain; Deitcher, David L

2002-01-01

The synaptic protein SNAP-25 is an important component of the neurotransmitter release machinery, although its precise function is still unknown. Genetic analysis of other synaptic proteins has yielded valuable information on their role in synaptic transmission. In this study, we performed a mutagenesis screen to identify new SNAP-25 alleles that fail to complement our previously isolated recessive temperature-sensitive allele of SNAP-25, SNAP-25(ts). In a screen of 100,000 flies, 26 F(1) progeny failed to complement SNAP-25(ts) and 21 of these were found to be null alleles of SNAP-25. These null alleles die at the pharate adult stage and electroretinogram recordings of these animals reveal that synaptic transmission is blocked. At the third instar larval stage, SNAP-25 nulls exhibit nearly normal neurotransmitter release at the neuromuscular junction. This is surprising since SNAP-25(ts) larvae exhibit a much stronger synaptic phenotype. Our evidence indicates that a related protein, SNAP-24, can substitute for SNAP-25 at the larval stage in SNAP-25 nulls. However, if a wild-type or mutant form of SNAP-25 is present, then SNAP-24 does not appear to take part in neurotransmitter release at the larval NMJ. These results suggest that the apparent redundancy between SNAP-25 and SNAP-24 is due to inappropriate genetic substitution. PMID:12242238

Complementation analysis of mutants of nitric oxide synthase reveals that the active site requires two hemes.

PubMed Central

Xie, Q W; Leung, M; Fuortes, M; Sassa, S; Nathan, C

1996-01-01

For catalytic activity, nitric oxide synthases (NOSs) must be dimeric. Previous work revealed that the requirements for stable dimerization included binding of tetrahydrobiopterin (BH4), arginine, and heme. Here we asked what function is served by dimerization. We assessed the ability of individually inactive mutants of mouse inducible NOS (iNOS; NOS2), each deficient in binding a particular cofactor or cosubstrate, to complement each other by generating NO upon cotransfection into human epithelial cells. The ability of the mutants to homodimerize was gauged by gel filtration and/or PAGE under partially denaturing conditions, both followed by immunoblot. Their ability to heterodimerize was assessed by coimmunoprecipitation. Heterodimers that contained only one COOH-terminal hemimer and only one BH4-binding site could both form and function, even though the NADPH-, FAD-, and FMN-binding domains (in the COOH-terminal hemimer) and the BH4-binding sites (in the NH2-terminal hemimer) were contributed by opposite chains. Heterodimers that contained only one heme-binding site (Cys-194) could also form, either in cis or in trans to the nucleotide-binding domains. However, for NO production, both chains had to bind heme. Thus, NO production by iNOS requires dimerization because the active site requires two hemes. Images Fig. 2 Fig. 3 Fig. 4 Fig. 7 PMID:8643499

Searching for long-lived particles: A compact detector for exotics at LHCb

DOE PAGES

Gligorov, Vladimir V.; Knapen, Simon; Papucci, Michele; ...

2018-01-31

We advocate for the construction of a new detector element at the LHCb experiment, designed to search for displaced decays of beyond Standard Model long-lived particles, taking advantage of a large shielded space in the LHCb cavern that is expected to soon become available. We discuss the general features and putative capabilities of such an experiment, as well as its various advantages and complementarities with respect to the existing LHC experiments and proposals such as SHiP and MATHUSLA. For two well-motivated beyond Standard Model benchmark scenarios—Higgs decay to dark photons and B meson decays via a Higgs mixing portal—the reachmore » either complements or exceeds that predicted for other LHC experiments.« less

Aistear vis-à-vis the Primary Curriculum: The Experiences of Early Years Teachers in Ireland

ERIC Educational Resources Information Center

Gray, Colette; Ryan, Anna

2016-01-01

Launched in 2009, the Aistear early years curriculum framework sought to complement and extend the primary school curriculum (PSC) at infant class level in the Republic of Ireland. While Aistear focuses on the development of attitudes, values and learning dispositions and is neither statutory nor inspected, the PSC centres on the acquisition of…

Complementing Classroom Learning through Outdoor Adventure Education: Out-of-School-Time Experiences That Make a Difference

ERIC Educational Resources Information Center

Richmond, Dan; Sibthorp, Jim; Gookin, John; Annarella, Sarah; Ferri, Stephanie

2018-01-01

Recent research underscores the importance of the skills, beliefs and behaviors that support student achievement in the classroom and beyond. This set of intrapersonal and interpersonal assets (e.g. perseverance, grit, social skills, efficacy beliefs and mind-sets) are often referred to as noncognitive factors, as they are not measured directly by…

A Healing Space: The Experiences of First Nations and Inuit Youth with Equine-Assisted Learning (EAL)

ERIC Educational Resources Information Center

Dell, Colleen Anne; Chalmers, Darlene; Bresette, Nora; Swain, Sue; Rankin, Deb; Hopkins, Carol

2011-01-01

The Nimkee NupiGawagan Healing Centre (NNHC) in Muncey, ON provides residential treatment to First Nations and Inuit youth who abuse solvents. As a complement to its culture-based programming, in 2008 the centre began offering weekly equine-assisted learning (EAL) curriculum to its clients in partnership with the Keystone Equine Centre and the…

Career Notes: Explore and Practice Personal Career Growth Skills. CHOICE (Challenging Options in Career Education).

ERIC Educational Resources Information Center

Gans, Connie; And Others

This text is the second in a series of advanced career education materials which, with an elementary segment, form a career education curriculum for elementary-secondary migrant students. Complementing texts on careers and roles and on work exploration and work experience, the text uses activities, poems, and cartoons to focus on self-awareness…

Experience from an Optional Dissection Course in a Clinically-Orientated Concept to Complement System-Based Anatomy in a Reformed Curriculum

ERIC Educational Resources Information Center

Eppler, Elisabeth; Serowy, Steffen; Link, Karl; Filgueira, Luis

2018-01-01

Profound anatomical knowledge is the basis for modern demands in medicine and surgery, but many countries worldwide including Australia and New Zealand have discontinued offering dissection courses to medical and dental students during the past decades. This educational project done in Australia aimed at enhancing basic and advanced anatomy…

Excavating and (Re)Presenting Stories: Narrative Inquiry as an Emergent Methodology in the Field of Adult Vocational Education and Technology

ERIC Educational Resources Information Center

Zimmerman, Aaron Samuel; Kim, Jeong-Hee

2017-01-01

Narrative inquiry has been a popular methodology in different disciplines for the last few decades. Using stories, narrative inquiry illuminates lived experience, serving as a valuable complement to research methodologies that are rooted in positivist epistemologies. In this article, we present a brief introduction to narrative inquiry including…

Antibody-mediated rejection in kidney transplantation: a review of pathophysiology, diagnosis, and treatment options.

PubMed

Kim, Miae; Martin, Spencer T; Townsend, Keri R; Gabardi, Steven

2014-07-01

Antibody-mediated rejection (AMR), also known as B-cell-mediated or humoral rejection, is a significant complication after kidney transplantation that carries a poor prognosis. Although fewer than 10% of kidney transplant patients experience AMR, as many as 30% of these patients experience graft loss as a consequence. Although AMR is mediated by antibodies against an allograft and results in histologic changes in allograft vasculature that differ from cellular rejection, it has not been recognized as a separate disease process until recently. With an improved understanding about the importance of the development of antibodies against allografts as well as complement activation, significant advances have occurred in the treatment of AMR. The standard of care for AMR includes plasmapheresis and intravenous immunoglobulin that remove and neutralize antibodies, respectively. Agents targeting B cells (rituximab and alemtuzumab), plasma cells (bortezomib), and the complement system (eculizumab) have also been used successfully to treat AMR in kidney transplant recipients. However, the high cost of these medications, their use for unlabeled indications, and a lack of prospective studies evaluating their efficacy and safety limit the routine use of these agents in the treatment of AMR in kidney transplant recipients. © 2014 Pharmacotherapy Publications, Inc.

CUVE - Cubesat UV Experiment: Unveil Venus' UV Absorber with Cubesat UV Mapping Spectrometer

NASA Astrophysics Data System (ADS)

Cottini, V.; Aslam, S.; D'Aversa, E.; Glaze, L.; Gorius, N.; Hewagama, T.; Ignatiev, N.; Piccioni, G.

2017-09-01

Our Venus mission concept Cubesat UV Experiment (CUVE) is one of ten proposals selected for funding by the NASA PSDS3 Program - Planetary Science Deep Space SmallSat Studies. CUVE concept is to insert a CubeSat spacecraft into a Venusian orbit and perform remote sensing of the UV spectral region using a high spectral resolution point spectrometer to resolve UV molecular bands, observe nightglow, and characterize the unidentified main UV absorber. The UV spectrometer is complemented by an imaging UV camera with multiple bands in the UV absorber main band range for contextual imaging. CUVE Science Objectives are: the nature of the "Unknown" UV-absorber; the abundances and distributions of SO2 and SO at and above Venus's cloud tops and their correlation with the UV absorber; the atmospheric dynamics at the cloud tops, structure of upper clouds and wind measurements from cloud-tracking; the nightglow emissions: NO, CO, O2. This mission will therefore be an excellent platform to study Venus' cloud top atmospheric properties where the UV absorption drives the planet's energy balance. CUVE would complement past, current and future Venus missions with conventional spacecraft, and address critical science questions cost effectively.

Continued Development of in Situ Geochronology for Planetary Using KArLE (Potassium-Argon Laser Experiment)

NASA Technical Reports Server (NTRS)

Devismes, D.; Cohen, B. A.

2016-01-01

Geochronology is a fundamental measurement for planetary samples, providing the ability to establish an absolute chronology for geological events, including crystallization history, magmatic evolution, and alteration events, and providing global and solar system context for such events. The capability for in situ geochronology will open up the ability for geochronology to be accomplished as part of lander or rover complement, on multiple samples rather than just those returned. An in situ geochronology package can also complement sample return missions by identifying the most interesting rocks to cache or return to Earth. The K-Ar radiometric dating approach to in situ dating has been validated by the Curiosity rover on Mars as well as several laboratories on Earth. Several independent projects developing in situ rock dating for planetary samples, based on the K-Ar method, are giving promising results. Among them, the Potassium (K)-Argon Laser Experiment (KArLE) at MSFC is based on techniques already in use for in planetary exploration, specifically, Laser-induced Breakdown Spectroscopy (LIBS, used on the Curiosity Chemcam), mass spectroscopy (used on multiple planetary missions, including Curiosity, ExoMars, and Rosetta), and optical imaging (used on most missions).

Let’s Tie the Knot: Marriage of Complement and Adaptive Immunity in Pathogen Evasion, for Better or Worse

PubMed Central

Bennett, Kaila M.; Rooijakkers, Suzan H. M.; Gorham, Ronald D.

2017-01-01

The complement system is typically regarded as an effector arm of innate immunity, leading to recognition and killing of microbial invaders in body fluids. Consequently, pathogens have engaged in an arms race, evolving molecules that can interfere with proper complement responses. However, complement is no longer viewed as an isolated system, and links with other immune mechanisms are continually being discovered. Complement forms an important bridge between innate and adaptive immunity. While its roles in innate immunity are well-documented, its function in adaptive immunity is less characterized. Therefore, it is no surprise that the field of pathogenic complement evasion has focused on blockade of innate effector functions, while potential inhibition of adaptive immune responses (via complement) has been overlooked to a certain extent. In this review, we highlight past and recent developments on the involvement of complement in the adaptive immune response. We discuss the mechanisms by which complement aids in lymphocyte stimulation and regulation, as well as in antigen presentation. In addition, we discuss microbial complement evasion strategies, and highlight specific examples in the context of adaptive immune responses. These emerging ties between complement and adaptive immunity provide a catalyst for future discovery in not only the field of adaptive immune evasion but in elucidating new roles of complement. PMID:28197139

Let's Tie the Knot: Marriage of Complement and Adaptive Immunity in Pathogen Evasion, for Better or Worse.

PubMed

Bennett, Kaila M; Rooijakkers, Suzan H M; Gorham, Ronald D

2017-01-01

The complement system is typically regarded as an effector arm of innate immunity, leading to recognition and killing of microbial invaders in body fluids. Consequently, pathogens have engaged in an arms race, evolving molecules that can interfere with proper complement responses. However, complement is no longer viewed as an isolated system, and links with other immune mechanisms are continually being discovered. Complement forms an important bridge between innate and adaptive immunity. While its roles in innate immunity are well-documented, its function in adaptive immunity is less characterized. Therefore, it is no surprise that the field of pathogenic complement evasion has focused on blockade of innate effector functions, while potential inhibition of adaptive immune responses (via complement) has been overlooked to a certain extent. In this review, we highlight past and recent developments on the involvement of complement in the adaptive immune response. We discuss the mechanisms by which complement aids in lymphocyte stimulation and regulation, as well as in antigen presentation. In addition, we discuss microbial complement evasion strategies, and highlight specific examples in the context of adaptive immune responses. These emerging ties between complement and adaptive immunity provide a catalyst for future discovery in not only the field of adaptive immune evasion but in elucidating new roles of complement.

Structural Basis for Antagonism by Suramin of Heparin Binding to Vaccinia Complement Protein

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ganesh, Vannakambadi K.; Muthuvel, Suresh Kumar; Smith, Scott A.

2010-07-19

Suramin is a competitive inhibitor of heparin binding to many proteins, including viral envelope proteins, protein tyrosine phosphatases, and fibroblast growth factors (FGFs). It has been clinically evaluated as a potential therapeutic in treatment of cancers caused by unregulated angiogenesis, triggered by FGFs. Although it has shown clinical promise in treatment of several cancers, suramin has many undesirable side effects. There is currently no experimental structure that reveals the molecular interactions responsible for suramin inhibition of heparin binding, which could be of potential use in structure-assisted design of improved analogues of suramin. We report the structure of suramin, in complexmore » with the heparin-binding site of vaccinia virus complement control protein (VCP), which interacts with heparin in a geometrically similar manner to many FGFs. The larger than anticipated flexibility of suramin manifested in this structure, and other details of VCP-suramin interactions, might provide useful structural information for interpreting interactions of suramin with many proteins.« less

Clinical polyomavirus BK variants with agnogene deletion are non-functional but rescued by trans-complementation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Myhre, Marit Renee; Olsen, Gunn-Hege; Gosert, Rainer

High-level replication of polyomavirus BK (BKV) in kidney transplant recipients is associated with the emergence of BKV variants with rearranged (rr) non-coding control region (NCCR) increasing viral early gene expression and cytopathology. Cloning and sequencing revealed the presence of a BKV quasispecies which included non-functional variants when assayed in a recombinant virus assay. Here we report that the rr-NCCR of BKV variants RH-3 and RH-12, both bearing a NCCR deletion including the 5' end of the agnoprotein coding sequence, mediated early and late viral reporter gene expression in kidney cells. However, in a recombinant virus they failed to produce infectiousmore » progeny despite large T-antigen and VP1 expression and the formation of nuclear virus-like particles. Infectious progeny was generated when the agnogene was reconstructed in cis or agnoprotein provided in trans from a co-existing BKV rr-NCCR variant. We conclude that complementation can rescue non-functional BKV variants in vitro and possibly in vivo.« less

The prozone effect exerted by the complement-binding anti-Lea on anti-D.

PubMed

Joshi, Sanmukh R; Parekh, Kamlesh H

2017-01-01

Prozone phenomenon is seen with very high-titer antibodies in an immune serum. The prozone effect on anti-D by a low-titer anti-Le a was investigated associated with neonatal jaundice. Standard methods were used in investigations. The child was born at full-term developed mild jaundice. With weak direct antiglobulin test+, her indirect serum bilirubin was progressed to 27.5 mg/dL in 48 h. Anti-D and anti-Le a were detected in the mother. Both these antibodies were detected in the child's serum though the eluate from red blood cells (RBCs) contained only anti-D. Mother's anti-D was masked by anti-Le a if the RBCs possessed both the antigens together. Anti-D was revealed only with D-positive RBCs lacking Le a or if the serum was modified by mixing with Le a+ saliva or was heated at 56°C or fortified with citrate solution. An anti-D showed prozone effect exerted by the complement-fixing anti-Le a in the test.

Complement-dependent cytotoxicity (CDC) to detect Anti-HLA antibodies: old but gold.

PubMed

Saito, Patrícia Keiko; Yamakawa, Roger Haruki; Pereira, Lucieni Christina Marques da Silva; da Silva, Waldir Veríssimo; Borelli, Sueli Donizete

2014-07-01

The criterion (gold) standard to detect anti-human leukocyte antigen (HLA) antibodies is the complement-dependent cytotoxicity (CDC) assay. Recently, more sensitive methods have been used for the same purpose. This study analyzed 70 serum samples of patients with end-stage renal disease using CDC, CDC with the addition of anti-human globulin (CDC-AHG), CDC with the addition of dithiothreitol (CDC-DTT), and the recent solid-phase immunoassay (SPI; Labscreen PRA) to detect anti-HLA antibodies. Mean percent panel reactive antibodies (PRA) detected by SPI was 37.5% (±34.2) higher than the values detected by the other methods. Comparative analyses revealed significant difference between CDC and CDC-AHG, and between CDC and SPI (P < 0.0001), but not between CDC-AHG and SPI (P = 0.8026). Although the CDC-AHG method is "old," its performance to detect anti-HLA antibodies in the samples analyzed was comparable to the SPI in the evaluation of percent class I PRA. © 2014 Wiley Periodicals, Inc.

Starch Catabolism by a Prominent Human Gut Symbiont Is Directed by the Recognition of Amylose Helices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koropatkin, Nicole M.; Martens, Eric C.; Gordon, Jeffrey I.

2009-01-12

The human gut microbiota performs functions that are not encoded in our Homo sapiens genome, including the processing of otherwise undigestible dietary polysaccharides. Defining the structures of proteins involved in the import and degradation of specific glycans by saccharolytic bacteria complements genomic analysis of the nutrient-processing capabilities of gut communities. Here, we describe the atomic structure of one such protein, SusD, required for starch binding and utilization by Bacteroides thetaiotaomicron, a prominent adaptive forager of glycans in the distal human gut microbiota. The binding pocket of this unique {alpha}-helical protein contains an arc of aromatic residues that complements the naturalmore » helical structure of starch and imposes this conformation on bound maltoheptaose. Furthermore, SusD binds cyclic oligosaccharides with higher affinity than linear forms. The structures of several SusD/oligosaccharide complexes reveal an inherent ligand recognition plasticity dominated by the three-dimensional conformation of the oligosaccharides rather than specific interactions with the composite sugars.« less

Xeroderma pigmentosum complementation group F: A rare cause of cerebellar ataxia with chorea.

PubMed

Carré, G; Marelli, C; Anheim, M; Geny, C; Renaud, M; Rezvani, H R; Koenig, M; Guissart, C; Tranchant, C

2017-05-15

The complementation group F of Xeroderma pigmentosum (XP-F) is rare in the Caucasian population, and usually devoid of neurological symptoms. We report two cases, both Caucasian, who exhibited progressive cerebellar ataxia, chorea, a mild subcortical frontal cognitive impairment, and in one case severe polyneuropathy. Brain MRI demonstrated cerebellar (2/2) and cortical (1/2) atrophy. Both patients had only mild sunburn sensitivity and no skin cancer. Mini-exome sequencing approach revealed in ERCC4, two heterozygous mutations, one of which was never described (c.580-584+1delCCAAGG, exon 3), in the first case, and an already reported homozygous mutation, in the second case. These cases emphasize that XP-F is a rare cause of recessive cerebellar ataxia and can in some cases clinically mimic Huntington's disease due to chorea and executive impairment. The association of ataxia, chorea, and sun hypersensitivity are major guidance for the diagnosis, which should not be missed, in order to prevent skin neoplastic complications. Copyright © 2017 Elsevier B.V. All rights reserved.

A widespread plant-fungal-bacterial symbiosis promotes plant biodiversity, plant nutrition and seedling recruitment

PubMed Central

van der Heijden, Marcel GA; Bruin, Susanne de; Luckerhoff, Ludo; van Logtestijn, Richard SP; Schlaeppi, Klaus

2016-01-01

Highly diverse microbial assemblages colonize plant roots. It is still poorly understood whether different members of this root microbiome act synergistically by supplying different services (for example, different limiting nutrients) to plants and plant communities. In order to test this, we manipulated the presence of two widespread plant root symbionts, arbuscular mycorrhizal fungi and nitrogen-fixing rhizobia bacteria in model grassland communities established in axenic microcosms. Here, we demonstrate that both symbionts complement each other resulting in increased plant diversity, enhanced seedling recruitment and improved nutrient acquisition compared with a single symbiont situation. Legume seedlings obtained up to 15-fold higher productivity if they formed an association with both symbionts, opposed to productivity they reached with only one symbiont. Our results reveal the importance of functional diversity of symbionts and demonstrate that different members of the root microbiome can complement each other in acquiring different limiting nutrients and in driving important ecosystem functions. PMID:26172208

Genetic control of the alternative pathway of complement in humans and age-related macular degeneration

PubMed Central

Hecker, Laura A.; Edwards, Albert O.; Ryu, Euijung; Tosakulwong, Nirubol; Baratz, Keith H.; Brown, William L.; Issa, Peter Charbel; Scholl, Hendrik P.; Pollok-Kopp, Beatrix; Schmid-Kubista, Katharina E.; Bailey, Kent R.; Oppermann, Martin

2010-01-01

Activation of the alternative pathway of complement is implicated in common neurodegenerative diseases including age-related macular degeneration (AMD). We explored the impact of common variation in genes encoding proteins of the alternative pathway on complement activation in human blood and in AMD. Genetic variation across the genes encoding complement factor H (CFH), factor B (CFB) and component 3 (C3) was determined. The influence of common haplotypes defining transcriptional and translational units on complement activation in blood was determined in a quantitative genomic association study. Individual haplotypes in CFH and CFB were associated with distinct and novel effects on plasma levels of precursors, regulators and activation products of the alternative pathway of complement in human blood. Further, genetic variation in CFH thought to influence cell surface regulation of complement did not alter plasma complement levels in human blood. Plasma markers of chronic activation (split-products Ba and C3d) and an activating enzyme (factor D) were elevated in AMD subjects. Most of the elevation in AMD was accounted for by the genetic variation controlling complement activation in human blood. Activation of the alternative pathway of complement in blood is under genetic control and increases with age. The genetic variation associated with increased activation of complement in human blood also increased the risk of AMD. Our data are consistent with a disease model in which genetic variation in the complement system increases the risk of AMD by a combination of systemic complement activation and abnormal regulation of complement activation in local tissues. PMID:19825847

Keeping It All Going-Complement Meets Metabolism.

PubMed

Kolev, Martin; Kemper, Claudia

2017-01-01

The complement system is an evolutionary old and crucial component of innate immunity, which is key to the detection and removal of invading pathogens. It was initially discovered as a liver-derived sentinel system circulating in serum, the lymph, and interstitial fluids that mediate the opsonization and lytic killing of bacteria, fungi, and viruses and the initiation of the general inflammatory responses. Although work performed specifically in the last five decades identified complement also as a critical instructor of adaptive immunity-indicating that complement's function is likely broader than initially anticipated-the dominant opinion among researchers and clinicians was that the key complement functions were in principle defined. However, there is now a growing realization that complement activity goes well beyond "classic" immune functions and that this system is also required for normal (neuronal) development and activity and general cell and tissue integrity and homeostasis. Furthermore, the recent discovery that complement activation is not confined to the extracellular space but occurs within cells led to the surprising understanding that complement is involved in the regulation of basic processes of the cell, particularly those of metabolic nature-mostly via novel crosstalks between complement and intracellular sensor, and effector, pathways that had been overlooked because of their spatial separation. These paradigm shifts in the field led to a renaissance in complement research and provide new platforms to now better understand the molecular pathways underlying the wide-reaching effects of complement functions in immunity and beyond. In this review, we will cover the current knowledge about complement's emerging relationship with the cellular metabolism machinery with a focus on the functional differences between serum-circulating versus intracellularly active complement during normal cell survival and induction of effector functions. We will also discuss how taking a closer look into the evolution of key complement components not only made the functional connection between complement and metabolism rather "predictable" but how it may also give clues for the discovery of additional roles for complement in basic cellular processes.

Complement in Lupus Nephritis: New Perspectives.

PubMed

Bao, Lihua; Cunningham, Patrick N; Quigg, Richard J

2015-09-01

Systemic lupus erythematosus (SLE) is an autoimmune disorder caused by loss of tolerance to self-antigens, the production of autoantibodies and deposition of complement-fixing immune complexes (ICs) in injured tissues. SLE is characterized by a wide range of clinical manifestations and targeted organs, with lupus nephritis being one of the most serious complications. The complement system consists of three pathways and is tightly controlled by a set of regulatory proteins to prevent injudicious complement activation on host tissue. The involvement of the complement system in the pathogenesis of SLE is well accepted; yet, its exact role is still not clear. Complement plays dual roles in the pathogenesis of SLE. On the one hand, the complement system appears to have protective features in that hereditary homozygous deficiencies of classical pathway components, such as C1q and C4, are associated with an increased risk for SLE. On the other hand, IC-mediated activation of complement in affected tissues is clearly evident in both experimental and human SLE along with pathological features that are logical consequences of complement activation. Studies in genetically altered mice have shown that lack of complement inhibitors, such as complement factor H (CFH) or decay-accelerating factor (DAF) accelerates the development of experimental lupus nephritis, while treatment with recombinant protein inhibitors, such as Crry-Ig, CR2-Crry, CR2-DAF and CR2-CFH, ameliorates the disease development. Complement-targeted drugs, including soluble complement receptor 1 (TP10), C1 esterase inhibitor and a monoclonal anti-C5 antibody (eculizumab), have been shown to inhibit complement safely, and are now being investigated in a variety of clinical conditions. SLE is an autoimmune disorder which targets multiple systems. Complement is centrally involved and plays dual roles in the pathogenesis of SLE. Studies from experimental lupus models and clinical trials support the use of complement-targeted therapy in the treatment of SLE.

First-Principles Predictions of Near-Edge X-ray Absorption Fine Structure Spectra of Semiconducting Polymers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Su, Gregory M.; Patel, Shrayesh N.; Pemmaraju, C. D.

The electronic structure and molecular orientation of semiconducting polymers in thin films determine their ability to transport charge. Methods based on near-edge X-ray absorption fine structure (NEXAFS) spectroscopy can be used to probe both the electronic structure and microstructure of semiconducting polymers in both crystalline and amorphous films. However, it can be challenging to interpret NEXAFS spectra on the basis of experimental data alone, and accurate, predictive calculations are needed to complement experiments. Here, we show that first-principles density functional theory (DFT) can be used to model NEXAFS spectra of semiconducting polymers and to identify the nature of transitions inmore » complicated NEXAFS spectra. Core-level X-ray absorption spectra of a set of semiconducting polymers were calculated using the excited electron and core-hole (XCH) approach based on constrained-occupancy DFT. A comparison of calculations on model oligomers and periodic structures with experimental data revealed the requirements for accurate prediction of NEXAFS spectra of both conjugated homopolymers and donor–acceptor polymers. The NEXAFS spectra predicted by the XCH approach were applied to study molecular orientation in donor–acceptor polymers using experimental spectra and revealed the complexity of using carbon edge spectra in systems with large monomeric units. The XCH approach has sufficient accuracy in predicting experimental NEXAFS spectra of polymers that it should be considered for design and analysis of measurements using soft X-ray techniques, such as resonant soft X-ray scattering and scanning transmission X-ray microscopy.« less

Visual target modulation of functional connectivity networks revealed by self-organizing group ICA.

PubMed

van de Ven, Vincent; Bledowski, Christoph; Prvulovic, David; Goebel, Rainer; Formisano, Elia; Di Salle, Francesco; Linden, David E J; Esposito, Fabrizio

2008-12-01

We applied a data-driven analysis based on self-organizing group independent component analysis (sogICA) to fMRI data from a three-stimulus visual oddball task. SogICA is particularly suited to the investigation of the underlying functional connectivity and does not rely on a predefined model of the experiment, which overcomes some of the limitations of hypothesis-driven analysis. Unlike most previous applications of ICA in functional imaging, our approach allows the analysis of the data at the group level, which is of particular interest in high order cognitive studies. SogICA is based on the hierarchical clustering of spatially similar independent components, derived from single subject decompositions. We identified four main clusters of components, centered on the posterior cingulate, bilateral insula, bilateral prefrontal cortex, and right posterior parietal and prefrontal cortex, consistently across all participants. Post hoc comparison of time courses revealed that insula, prefrontal cortex and right fronto-parietal components showed higher activity for targets than for distractors. Activation for distractors was higher in the posterior cingulate cortex, where deactivation was observed for targets. While our results conform to previous neuroimaging studies, they also complement conventional results by showing functional connectivity networks with unique contributions to the task that were consistent across subjects. SogICA can thus be used to probe functional networks of active cognitive tasks at the group-level and can provide additional insights to generate new hypotheses for further study. Copyright 2007 Wiley-Liss, Inc.

NASA Lewis' Telescience Support Center Supports Orbiting Microgravity Experiments

NASA Technical Reports Server (NTRS)

Hawersaat, Bob W.

1998-01-01

The Telescience Support Center (TSC) at the NASA Lewis Research Center was developed to enable Lewis-based science teams and principal investigators to monitor and control experimental and operational payloads onboard the International Space Station. The TSC is a remote operations hub that can interface with other remote facilities, such as universities and industrial laboratories. As a pathfinder for International Space Station telescience operations, the TSC has incrementally developed an operational capability by supporting space shuttle missions. The TSC has evolved into an environment where experimenters and scientists can control and monitor the health and status of their experiments in near real time. Remote operations (or telescience) allow local scientists and their experiment teams to minimize their travel and maintain a local complement of expertise for hardware and software troubleshooting and data analysis. The TSC was designed, developed, and is operated by Lewis' Engineering and Technical Services Directorate and its support contractors, Analex Corporation and White's Information System, Inc. It is managed by Lewis' Microgravity Science Division. The TSC provides operational support in conjunction with the NASA Marshall Space Flight Center and NASA Johnson Space Center. It enables its customers to command, receive, and view telemetry; monitor the science video from their on-orbit experiments; and communicate over mission-support voice loops. Data can be received and routed to experimenter-supplied ground support equipment and/or to the TSC data system for display. Video teleconferencing capability and other video sources, such as NASA TV, are also available. The TSC has a full complement of standard services to aid experimenters in telemetry operations.

Why Do Students Engage in Elective Courses on Acupuncture and Homeopathy at Medical School? A Survey.

PubMed

Jocham, Alexandra; Berberat, Pascal O; Schneider, Antonius; Linde, Klaus

We aimed to investigate why medical students in Germany participate in elective courses on acupuncture or homeopathy. The study was a nationwide, cross-sectional survey. Elective courses on acupuncture and homeopathy in the academic half-year 2013/14 were identified by inquiries directed to all 37 German medical schools, to student initiatives, and organizations supporting such courses. Participants of courses were asked to fill in a questionnaire consisting of a free-text question on their motives and closed questions regarding personal experiences, personal environment, evidence, role of the therapy as a complement to conventional medicine, and opportunistic aspects in relation to the therapy chosen. Students participating in 16 of 18 identified acupuncture courses (n = 220) and 12 of 13 identified homeopathy courses (n = 113) filled in the questionnaire. Content analysis of the free text showed that personal experience, a feeling that conventional medicine is somehow incomplete, the belief that acupuncture or homeopathy could help to overcome this shortcoming, and positive characteristics attributed to the therapies were the main motives for participation. Quantitative analyses showed that own experiences and considering the therapy a useful complement to conventional medicine were similarly rated motives in both groups, while opportunistic aspects played almost no role. The influence of the personal environment was more important among homeopathy students, while acupuncture students considered their therapy better backed by evidence. In our survey, personal experiences and the belief that acupuncture or homeopathy allows grasping the patient more holistically were primary motives for participation. © 2017 S. Karger GmbH, Freiburg.

Spontaneous mutation reveals influence of exopolysaccharide on Lactobacillus johnsonii surface characteristics.

PubMed

Horn, Nikki; Wegmann, Udo; Dertli, Enes; Mulholland, Francis; Collins, Samuel R A; Waldron, Keith W; Bongaerts, Roy J; Mayer, Melinda J; Narbad, Arjan

2013-01-01

As a competitive exclusion agent, Lactobacillus johnsonii FI9785 has been shown to prevent the colonization of selected pathogenic bacteria from the chicken gastrointestinal tract. During growth of the bacterium a rare but consistent emergence of an altered phenotype was noted, generating smooth colonies in contrast to the wild type rough form. A smooth colony variant was isolated and two-dimensional gel analysis of both strains revealed a protein spot with different migration properties in the two phenotypes. The spot in both gels was identified as a putative tyrosine kinase (EpsC), associated with a predicted exopolysaccharide gene cluster. Sequencing of the epsC gene from the smooth mutant revealed a single substitution (G to A) in the coding strand, resulting in the amino acid change D88N in the corresponding gene product. A native plasmid of L. johnsonii was engineered to produce a novel vector for constitutive expression and this was used to demonstrate that expression of the wild type epsC gene in the smooth mutant produced a reversion to the rough colony phenotype. Both the mutant and epsC complemented strains had increased levels of exopolysaccharides compared to the wild type strain, indicating that the rough phenotype is not solely associated with the quantity of exopolysaccharide. Another gene in the cluster, epsE, that encoded a putative undecaprenyl-phosphate galactosephosphotransferase, was deleted in order to investigate its role in exopolysaccharide biosynthesis. The ΔepsE strain exhibited a large increase in cell aggregation and a reduction in exopolysaccharide content, while plasmid complementation of epsE restored the wild type phenotype. Flow cytometry showed that the wild type and derivative strains exhibited clear differences in their adhesive ability to HT29 monolayers in tissue culture, demonstrating an impact of EPS on surface properties and bacteria-host interactions.

Protein profiling in serum after traumatic brain injury in rats reveals potential injury markers.

PubMed

Thelin, Eric Peter; Just, David; Frostell, Arvid; Häggmark-Månberg, Anna; Risling, Mårten; Svensson, Mikael; Nilsson, Peter; Bellander, Bo-Michael

2018-03-15

The serum proteome following traumatic brain injury (TBI) could provide information for outcome prediction and injury monitoring. The aim with this affinity proteomic study was to identify serum proteins over time and between normoxic and hypoxic conditions in focal TBI. Sprague Dawley rats (n=73) received a 3mm deep controlled cortical impact ("severe injury"). Following injury, the rats inhaled either a normoxic (22% O 2 ) or hypoxic (11% O 2 ) air mixture for 30min before resuscitation. The rats were sacrificed at day 1, 3, 7, 14 and 28 after trauma. A total of 204 antibodies targeting 143 unique proteins of interest in TBI research, were selected. The sample proteome was analyzed in a suspension bead array set-up. Comparative statistics and factor analysis were used to detect differences as well as variance in the data. We found that complement factor 9 (C9), complement factor B (CFB) and aldolase c (ALDOC) were detected at higher levels the first days after trauma. In contrast, hypoxia inducing factor (HIF)1α, amyloid precursor protein (APP) and WBSCR17 increased over the subsequent weeks. S100A9 levels were higher in hypoxic-compared to normoxic rats, together with a majority of the analyzed proteins, albeit few reached statistical significance. The principal component analysis revealed a variance in the data, highlighting clusters of proteins. Protein profiling of serum following TBI using an antibody based microarray revealed temporal changes of several proteins over an extended period of up to four weeks. Further studies are warranted to confirm our findings. Copyright © 2016 The Author(s). Published by Elsevier B.V. All rights reserved.

Evasion of Complement-Mediated Lysis and Complement C3 Deposition Are Regulated by Francisella tularensis Lipopolysaccharide O Antigen1

PubMed Central

Clay, Corey D.; Soni, Shilpa; Gunn, John S.; Schlesinger, Larry S.

2009-01-01

The bacterium Francisella tularensis (Ft) is a potential weapon of bioterrorism when aerosolized. Macrophage infection is necessary for disease progression and efficient phagocytosis by human macrophages requires serum opsonization by complement. Microbial complement activation leads to surface deposition of a highly regulated protein complex resulting in opsonization or membrane lysis. The nature of complement component C3 deposition, i.e., C3b (opsonization and lysis) or C3bi (opsonization only) fragment deposition, is central to the outcome of activation. In this study, we examine the mechanisms of Ft resistance to complement-mediated lysis, C3 component deposition on the Ft surface, and complement activation. Upon incubation in fresh nonimmune human serum, Schu S4 (Ft subsp. tularensis), Fn (Ft subsp. novicida), and LVS (Ft subsp. holarctica live vaccine strain) were resistant to complement-mediated lysis, but LVSG and LVSR (LVS strains altered in surface carbohydrate structures) were susceptible. C3 deposition, however, occurred on all strains. Complement-susceptible strains had markedly increased C3 fragment deposition, including the persistent presence of C3b compared with C3bi, which indicates that C3b inactivation results in survival of complement-resistant strains. C1q, an essential component of the classical activation pathway, was necessary for lysis of complement-susceptible strains and optimal C3 deposition on all strains. Finally, use of Francisella LPS mutants confirmed O Ag as a major regulator of complement resistance. These data provide evidence that pathogenic Francisella activate complement, but are resistant to complement-mediated lysis in part due to limited C3 deposition, rapid conversion of surface-bound C3b to C3bi, and the presence of LPS O Ag. PMID:18832715

NETosing Neutrophils Activate Complement Both on Their Own NETs and Bacteria via Alternative and Non-alternative Pathways

PubMed Central

Yuen, Joshua; Pluthero, Fred G.; Douda, David N.; Riedl, Magdalena; Cherry, Ahmed; Ulanova, Marina; Kahr, Walter H. A.; Palaniyar, Nades; Licht, Christoph

2016-01-01

Neutrophils deposit antimicrobial proteins, such as myeloperoxidase and proteases on chromatin, which they release as neutrophil extracellular traps (NETs). Neutrophils also carry key components of the complement alternative pathway (AP) such as properdin or complement factor P (CFP), complement factor B (CFB), and C3. However, the contribution of these complement components and complement activation during NET formation in the presence and absence of bacteria is poorly understood. We studied complement activation on NETs and a Gram-negative opportunistic bacterial pathogen Pseudomonas aeruginosa (PA01, PAKwt, and PAKgfp). Here, we show that anaphylatoxin C5a, formyl-methionyl-leucyl-phenylalanine (fMLP) and phorbol myristate acetate (PMA), which activates NADPH oxidase, induce the release of CFP, CFB, and C3 from neutrophils. In response to PMA or P. aeruginosa, neutrophils secrete CFP, deposit it on NETs and bacteria, and induce the formation of terminal complement complexes (C5b–9). A blocking anti-CFP antibody inhibited AP-mediated but not non-AP-mediated complement activation on NETs and P. aeruginosa. Therefore, NET-mediated complement activation occurs via both AP- and non AP-based mechanisms, and AP-mediated complement activation during NETosis is dependent on CFP. These findings suggest that neutrophils could use their “AP tool kit” to readily activate complement on NETs and Gram-negative bacteria, such as P. aeruginosa, whereas additional components present in the serum help to fix non-AP-mediated complement both on NETs and bacteria. This unique mechanism may play important roles in host defense and help to explain specific roles of complement activation in NET-related diseases. PMID:27148258

Blood SC5b-9 complement levels increase at parturition during term and preterm labor.

PubMed

Segura-Cervantes, Enrique; Mancilla-Ramirez, Javier; Zurita, Luis; Paredes, Yuriria; Arredondo, José Luis; Galindo-Sevilla, Norma

2015-06-01

We explored the hypothesis that complement, an innate and adaptive immune effector, is active in the plasma of parturient women and is deposited on fetal membranes collected after delivery. A cross-sectional study was designed to evaluate complement activity at parturition. Pregnant women (n = 97) between 15 and 41 years of age were enrolled in a hospital protocol during the perinatal period to assess both SC5b-9 complement activity in blood and complement deposition on fetal membranes during parturition. Soluble SC5b-9 complement activity in plasma fractions was measured using a standard enzyme-linked immunosorbent assay (ELISA) that included specific anti-complement antibodies. Complement deposition on membranes was analyzed using immuno-dot blots and immunohistochemistry. Soluble SC5b-9 complement complex levels were increased in the plasma of women during term labor (TL; median 3361; range 1726-5670 ng/mL), preterm labor (PL; median 2958; range 1552-7092 ng/mL), and preterm premature rupture of membranes (PPROM; median 2272; range 167-6540 ng/mL) compared with pregnant women who were not in labor (P; median 1384; range 174-4570 ng/mL; P < 0.001, Kruskal-Wallis test). Active complement, as assessed by the C9 neo-antigen in C5b-9 complexes, was deposited on fetal membranes, with no difference between term and preterm delivery. The deposition of active complement on fetal membranes was confirmed by immunohistochemistry. Women who underwent non-labor-indicated Cesarean sections did not exhibit complement deposition. Soluble SC5b-9 complement complex levels increased in the plasma of women during parturition, and complement C5b-9 complexes were deposited on fetal membranes. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Complement-Mediated Enhancement of Monocyte Adhesion to Endothelial Cells by HLA Antibodies, and Blockade by a Specific Inhibitor of the Classical Complement Cascade, TNT003

PubMed Central

Valenzuela, Nicole M.; Thomas, Kimberly A.; Mulder, Arend; Parry, Graham C.; Panicker, Sandip; Reed, Elaine F.

2017-01-01

Background Antibody-mediated rejection (AMR) of most solid organs is characterized by evidence of complement activation and/or intragraft macrophages (C4d + and CD68+ biopsies). We previously demonstrated that crosslinking of HLA I by antibodies triggered endothelial activation and monocyte adhesion. We hypothesized that activation of the classical complement pathway at the endothelial cell surface by HLA antibodies would enhance monocyte adhesion through soluble split product generation, in parallel with direct endothelial activation downstream of HLA signaling. Methods Primary human aortic endothelial cells (HAEC) were stimulated with HLA class I antibodies in the presence of intact human serum complement. C3a and C5a generation, endothelial P-selectin expression, and adhesion of human primary and immortalized monocytes (Mono Mac 6) were measured. Alternatively, HAEC or monocytes were directly stimulated with purified C3a or C5a. Classical complement activation was inhibited by pretreatment of complement with an anti-C1s antibody (TNT003). Results Treatment of HAEC with HLA antibody and human complement increased the formation of C3a and C5a. Monocyte recruitment by human HLA antibodies was enhanced in the presence of intact human serum complement or purified C3a or C5a. Specific inhibition of the classical complement pathway using TNT003 or C1q-depleted serum significantly reduced adhesion of monocytes in the presence of human complement. Conclusions Despite persistent endothelial viability in the presence of HLA antibodies and complement, upstream complement anaphylatoxin production exacerbates endothelial exocytosis and leukocyte recruitment. Upstream inhibition of classical complement may be therapeutic to dampen mononuclear cell recruitment and endothelial activation characteristic of microvascular inflammation during AMR. PMID:28640789

Hijacking Complement Regulatory Proteins for Bacterial Immune Evasion.

PubMed

Hovingh, Elise S; van den Broek, Bryan; Jongerius, Ilse

2016-01-01

The human complement system plays an important role in the defense against invading pathogens, inflammation and homeostasis. Invading microbes, such as bacteria, directly activate the complement system resulting in the formation of chemoattractants and in effective labeling of the bacteria for phagocytosis. In addition, formation of the membrane attack complex is responsible for direct killing of Gram-negative bacteria. In turn, bacteria have evolved several ways to evade complement activation on their surface in order to be able to colonize and invade the human host. One important mechanism of bacterial escape is attraction of complement regulatory proteins to the microbial surface. These molecules are present in the human body for tight regulation of the complement system to prevent damage to host self-surfaces. Therefore, recruitment of complement regulatory proteins to the bacterial surface results in decreased complement activation on the microbial surface which favors bacterial survival. This review will discuss recent advances in understanding the binding of complement regulatory proteins to the bacterial surface at the molecular level. This includes, new insights that have become available concerning specific conserved motives on complement regulatory proteins that are favorable for microbial binding. Finally, complement evasion molecules are of high importance for vaccine development due to their dominant role in bacterial survival, high immunogenicity and homology as well as their presence on the bacterial surface. Here, the use of complement evasion molecules for vaccine development will be discussed.

Hijacking Complement Regulatory Proteins for Bacterial Immune Evasion

PubMed Central

Hovingh, Elise S.; van den Broek, Bryan; Jongerius, Ilse

2016-01-01

The human complement system plays an important role in the defense against invading pathogens, inflammation and homeostasis. Invading microbes, such as bacteria, directly activate the complement system resulting in the formation of chemoattractants and in effective labeling of the bacteria for phagocytosis. In addition, formation of the membrane attack complex is responsible for direct killing of Gram-negative bacteria. In turn, bacteria have evolved several ways to evade complement activation on their surface in order to be able to colonize and invade the human host. One important mechanism of bacterial escape is attraction of complement regulatory proteins to the microbial surface. These molecules are present in the human body for tight regulation of the complement system to prevent damage to host self-surfaces. Therefore, recruitment of complement regulatory proteins to the bacterial surface results in decreased complement activation on the microbial surface which favors bacterial survival. This review will discuss recent advances in understanding the binding of complement regulatory proteins to the bacterial surface at the molecular level. This includes, new insights that have become available concerning specific conserved motives on complement regulatory proteins that are favorable for microbial binding. Finally, complement evasion molecules are of high importance for vaccine development due to their dominant role in bacterial survival, high immunogenicity and homology as well as their presence on the bacterial surface. Here, the use of complement evasion molecules for vaccine development will be discussed. PMID:28066340

Complement Constructions in English: Fairly Difficult for EFL Language Learners

ERIC Educational Resources Information Center

Fazeli, Fatemeh; Shokrpour, Nasrin

2012-01-01

Complement constructions vary significantly in English and Persian. There are more complementation structures in English than in Persian and a complement structure in Persian might have more than one equivalent in English. Producing complement structures (CSs) in English is very difficult for native speakers of Persian, especially in an EFL…