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Sample records for c3 ssti polymorphism

  1. C3 Polymorphism Influences Circulating Levels of C3, ASP and Lipids in Schizophrenic Patients.

    PubMed

    Nsaiba, Mohamed Jalloul; Lapointe, Marc; Mabrouk, Hajer; Douki, Wahiba; Gaha, Lotfi; Pérusse, Louis; Bouchard, Claude; Jrad, Besma Bel Hadj; Cianflone, Katherine

    2015-05-01

    Excessive activation of complement is associated with many diseases including schizophrenia. Investigation of C3 polymorphisms, circulating C3, cleavage product ASP/C3adesArg, and lipid metabolism. Cross-sectional analysis. C3 genotyping (CC vs GG for R102L) was performed on 434 Tunisian people consisting of 272 schizophrenic (SZ) patients and 162 control subjects. In a age- and gender-matched subgroups of the three genotypes (131 SZ and 112 NOR), plasma triglycerides, total cholesterol (C), LDL-C, HDL-C, ASP, and complement C3 were measured. C3 gene polymorphism influences BMI and plasma C3, ASP, triglyceride, total cholesterol, LDL-C and HDL-C among SZ patients (p < 0.05-0.0001), with increasing values demonstrated from CC (common form) to CG (heterozygote form) to GG (rare homozygote) forms. Significant correlations between plasma C3 and BMI, triglyceride, HDL-C and ASP (p < 0.05-0.0001) were observed, while ASP correlated with BMI and LDL-C (p = 0.005, p = 0.001, respectively) in SZ patients. Further, proportional conversion of C3 to ASP (%ASP/C3) also increased (p < 0.0001, GG>CG>CC). C3 polymorphisms and plasma C3, ASP and %ASP/C3 correlated with lipid parameters in this SZ population, suggesting that factors predisposing patients to schizophrenia are permissive for complement pathway activation and dyslipidemic influences.

  2. SSTI- Lewis Spacecraft Nickel-Hydrogen Battery

    NASA Technical Reports Server (NTRS)

    Tobias, R. F.

    1997-01-01

    Topics considered include: NASA-Small Spacecraft Technology Initiative (SSTI) objectives, SSTI-Lewis overview, battery requirement, two cells Common Pressure Vessel (CPV) design summary, CPV electric performance, battery design summary, battery functional description, battery performance.

  3. NASA SSTI CLARK 3-meter imaging satellite

    NASA Technical Reports Server (NTRS)

    Sebestyen, George; Hayduk, Robert J.

    1996-01-01

    Within the framework of NASA's Small Satellite Technology Initiative (SSTI) CLARK program, the development of a high technology small satellite is reported on. The satellite will provide 3 m resolution panchromatic and 15 m resolution multispectral image capabilities. The satellite, programmed for launch in 1996, will be in a sun-synchronous orbit and includes the following systems: three-axis zero momentum attitude control; hydrazine propulsion for stationkeeping; Global Positioning System satellite position and star tracker attitude determination; and onboard image storage capability. The objectives of the SSTI CLARK program, the technical characteristics of the satellite, the techniques employed to reduce costs, and the image processing, archiving and distribution are described.

  4. Spacecraft System Integration and Test: SSTI Lewis critical design audit

    NASA Technical Reports Server (NTRS)

    Brooks, R. P.; Cha, K. K.

    1995-01-01

    The Critical Design Audit package is the final detailed design package which provides a comprehensive description of the SSTI mission. This package includes the program overview, the system requirements, the science and applications activities, the ground segment development, the assembly, integration and test description, the payload and technology demonstrations, and the spacecraft bus subsystems. Publication and presentation of this document marks the final requirements and design freeze for SSTI.

  5. Apolipoprotein C3 polymorphism is associated with cognitive function in Caribbean Hispanics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Apolipoprotein C3(APOC3) modulates triglyceride metabolism through inhibition of lipoprotein lipase, but is itself regulated by insulin, so that APOC3 represents a potential mechanism by which glucose metabolism may affect lipid metabolism. Unfavorable lipoprotein profiles and impaired ...

  6. Association of Apolipoprotein C3 Genetic Polymorphisms with the Risk of Ischemic Stroke in the Northern Chinese Han Population

    PubMed Central

    Wang, Yanzhe; Yin, Xiaoyu; Li, Lei; Deng, Shumin; He, Zhiyi

    2016-01-01

    The apolipoprotein C3 (APOC3) gene, which is a member of the APOA1/C3/A4/A5 gene cluster, plays a crucial role in lipid metabolism. Dyslipidemia is an important risk factor for ischemic stroke. In the present study, we performed a hospital-based case—control study of 895 ischemic stroke patients and 883 control subjects to examine the effects of four APOC3 single nucleotide polymorphisms (SNPs) (rs2854116, rs2854117, rs4520 and rs5128) on the risk of ischemic stroke in a northern Chinese Han population. The SNaPshot Multiplex sequencing assay was used for SNP genotyping, and the potential association of genotype distributions and allele frequencies with ischemic stroke was analyzed statistically. Compared with the GG genotype, the CC+GC genotype of rs5128 was significantly associated with an increased risk in females (adjusted OR = 3.38, 95% CI = 1.82–6.28, P <0.01) after all of the risk factors were adjusted for with logistic regression analyses. A similar relationship was found between the rs4520 polymorphism and ischemic stroke risk in Han Chinese women. Under a recessive genetic model, the TT+TC genotypes of this variant increased ischemic stroke risk (adjusted OR = 2.05; 95% CI = 1.28–3.29; P <0.01). Haplotype analysis revealed that in males, the T-C-T-C haplotype of rs2854116-rs2854117-rs4520-rs5128 was significantly more frequent in the ischemic stroke group than in the control group (OR = 1.49, 95% CI = 1.18–1.87, P<0.01). The results of our study indicate that the APOC3 polymorphisms contribute to ischemic stroke susceptibility in females in the northern Chinese Han population. PMID:27690381

  7. System Critical Design Audit (CDA). Books 1, 2 and 3; [Small Satellite Technology Initiative (SSTI Lewis Spacecraft Program)

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Small Satellite Technology Initiative (SSTI) Lewis Spacecraft Program is evaluated. Spacecraft integration, test, launch, and spacecraft bus are discussed. Payloads and technology demonstrations are presented. Mission data management system and ground segment are also addressed.

  8. Autonomous Navigation of the SSTI/Lewis Spacecraft Using the Global Positioning System (GPS)

    NASA Technical Reports Server (NTRS)

    Hart, R. C.; Long, A. C.; Lee, T.

    1997-01-01

    The National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD) is pursuing the application of Global Positioning System (GPS) technology to improve the accuracy and economy of spacecraft navigation. High-accuracy autonomous navigation algorithms are being flight qualified in conjunction with GSFC's GPS Attitude Determination Flyer (GADFLY) experiment on the Small Satellite Technology Initiative (SSTI) Lewis spacecraft, which is scheduled for launch in 1997. Preflight performance assessments indicate that these algorithms can provide a real-time total position accuracy of better than 10 meters (1 sigma) and velocity accuracy of better than 0.01 meter per second (1 sigma), with selective availability at typical levels. This accuracy is projected to improve to the 2-meter level if corrections to be provided by the GPS Wide Area Augmentation System (WAAS) are included.

  9. C3 glomerulopathy: consensus report

    PubMed Central

    Pickering, Matthew C; D'Agati, Vivette D; Nester, Carla M; Smith, Richard J; Haas, Mark; Appel, Gerald B; Alpers, Charles E; Bajema, Ingeborg M; Bedrosian, Camille; Braun, Michael; Doyle, Mittie; Fakhouri, Fadi; Fervenza, Fernando C; Fogo, Agnes B; Frémeaux-Bacchi, Véronique; Gale, Daniel P; Goicoechea de Jorge, Elena; Griffin, Gene; Harris, Claire L; Holers, V Michael; Johnson, Sally; Lavin, Peter J; Medjeral-Thomas, Nicholas; Paul Morgan, B; Nast, Cynthia C; Noel, Laure-Hélène; Peters, D Keith; Rodríguez de Córdoba, Santiago; Servais, Aude; Sethi, Sanjeev; Song, Wen-Chao; Tamburini, Paul; Thurman, Joshua M; Zavros, Michael; Cook, H Terence

    2013-01-01

    C3 glomerulopathy is a recently introduced pathological entity whose original definition was glomerular pathology characterized by C3 accumulation with absent or scanty immunoglobulin deposition. In August 2012, an invited group of experts (comprising the authors of this document) in renal pathology, nephrology, complement biology, and complement therapeutics met to discuss C3 glomerulopathy in the first C3 Glomerulopathy Meeting. The objectives were to reach a consensus on: the definition of C3 glomerulopathy, appropriate complement investigations that should be performed in these patients, and how complement therapeutics should be explored in the condition. This meeting report represents the current consensus view of the group. PMID:24172683

  10. Apolipoprotein A1/C3/A5 haplotypes and serum lipid levels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The association of single nucleotide polymorphisms (SNPs) in the apolipoprotein (Apo) A1/C3/A4/A5 gene cluster and serum lipid profiles is inconsistent. The present study was undertaken to detect the association between the ApoA1/C3/A5 gene polymorphisms and their haplotypes with serum lipid levels ...

  11. Complement component 3 (C3)

    MedlinePlus

    C3 and C4 are the most commonly measured complement components. A complement test may be used to monitor people with an ... normal levels of the complement proteins C3 and C4 . Complement activity varies throughout the body. For example, ...

  12. The Speaking Section of the TOEFL iBT[TM] (SSTiBT): Test-Takers' Reported Strategic Behaviors. TOEFL iBT[TM] Research Report. RR-09-30

    ERIC Educational Resources Information Center

    Swain, Merrill; Huang, Li-Shih; Barkaoui, Khaled; Brooks, Lindsay; Lapkin, Sharon

    2009-01-01

    This study responds to the Test of English as a Foreign Language[TM] (TOEFL[R]) research agenda concerning the need to understand the processes and knowledge that test-takers utilize. Specifically, it investigates the strategic behaviors test-takers reported using when taking the Speaking section of the TOEFL iBT[TM] (SSTiBT). It also investigates…

  13. Overview of C3 Glomerulopathy

    PubMed Central

    Master Sankar Raj, Vimal; Gordillo, Roberto; Chand, Deepa H.

    2016-01-01

    C3 glomerulopathy is an umbrella term, which includes several rare forms of glomerulonephritis (GN) with underlying defects in the alternate complement cascade. A common histological feature noted in all these GN is dominant C3 deposition in the glomerulus. In this review, we will provide an overview of the complement system as well as mediators, with an introduction to pharmaceutical agents that can alter the pathway. PMID:27200326

  14. Update on C3 glomerulopathy

    PubMed Central

    Barbour, Thomas D.; Ruseva, Marieta M.; Pickering, Matthew C.

    2016-01-01

    C3 glomerulopathy refers to a disease process in which abnormal control of complement activation, degradation or deposition results in predominant C3 fragment deposition within the glomerulus and glomerular damage. Recent studies have improved our understanding of its pathogenesis. The key abnormality is uncontrolled C3b amplification in the circulation and/or along the glomerular basement membrane. Family studies in which disease segregates with structurally abnormal complement factor H-related (CFHR) proteins demonstrate that abnormal CFHR proteins are important in some types of C3 glomerulopathy. This is currently thought to be due to the ability of these proteins to antagonize the major negative regulator of C3 activation, complement factor H (CFH), a process termed ‘CFH de-regulation’. Recent clinicopathological cohort studies have led to further refinements in case definition, culminating in a 2013 consensus report, which provides recommendations regarding investigation and treatment. Early clinical experience with complement-targeted therapeutics, notably C5 inhibitors, has also now been published. Here, we summarize the latest developments in C3 glomerulopathy. PMID:25326473

  15. Lifetimes of the {A} States of C_3, C_3-NE, and C_3-AR

    NASA Astrophysics Data System (ADS)

    Wang, Yi-Jen; Chen, Chiao-Wei; Zhou, Liuzhu; Merer, Anthony J.; Hsu, Yen-Chu

    2012-06-01

    The fluorescence lifetimes of the ˜{A} states of C_3, C_3-Ne and C_3-Ar have been measured under supersonic molecular beam conditions. To minimize possible collisional quenching, the lifetimes of all three species were measured at a distance of about 42 nozzle diameters from the orifice. For all the vibrational levels of the ˜{A} state of the C_3 monomer, only J'=1 lifetimes were recorded, using R(0) lines. The accuracy of the lifetimes obtained was estimated to be better than 3ns. General features of the lifetimes of the C_3 monomer are as follows: with increasing excitation of the symmetric stretching vibration, the lifetimes increase to a maximum at v_1=4. Bending excitation reduces the lifetimes, though exceptions occur for the 0 v 0 and 1 v 0 levels. Among all the vibrational levels, 0 2^- 0, 0 4^- 0, and 0 2^+ 0 have the shortest lifetimes, similar to that of the origin level. Lifetimes of the ˜{A} state of C_3-Ne and C_3-Ar have only been measured for features 1.5-2 and 11-14 cm-1, respectively, to the red of the R(0) lines of the ˜{A}-˜{X} bands of free C_3. It is not possible to reduce the backing pressure while measuring lifetimes of the complexes; we therefore reduced the average pressure of the chamber to 1-2x10-5 torr by lowering the repetition rate. No sign of predissociation was found in the Ne complex except for the level 0 12^+ 0. The lifetimes of the complexes did not vary with vibration in the manner found for C_3 itself. The lifetime of the 0 2^- 0 level, one of the lowest vibrational levels of the ˜{A} state, was not affected by complexing with either Ne or Ar, consistent with the observation that the least van der Waals shifts were observed for this vibrational level. G. Zhang, K.-S. Chen, A. J. Merer, Y.-C. Hsu, W.-J. Chen, S. Shaji, and Y.-A. Liao, J. Chem. Phys. 122, 244308 (2005). G. Zhang, B.-G. Lin, S.-M. Wen, and Y.-C. Hsu, J. Chem. Phys. 120, 3189 (2004).

  16. The Importance of the C3 Framework

    ERIC Educational Resources Information Center

    Social Education, 2013

    2013-01-01

    "The C3 Framework for Social Studies State Standards will soon be released under the title "The College, Career, and Civic Life (C3) Framework for Social Studies State Standards: State Guidance for Enhancing the Rigor of K-12 Civics, Economics, Geography, and History." The C3 Project Director and Lead Writer was NCSS member Kathy…

  17. Vimentin mediates uptake of C3 exoenzyme.

    PubMed

    Rohrbeck, Astrid; Schröder, Anke; Hagemann, Sandra; Pich, Andreas; Höltje, Markus; Ahnert-Hilger, Gudrun; Just, Ingo

    2014-01-01

    Clostridium botulinum C3 exoenzyme (C3) selectively inactivates RhoA/B/C GTPases by ADP-ribosylation. Based on this substrate specificity C3 is a well-established tool in cell biology. C3 is taken up by eukaryotic cells although lacking an uptake and translocation domain. Based on different approaches vimentin was identified as membranous C3-interaction partner by mass spectrometry. Vimentin in fact was partly localized at the outer surface of hippocampal HT22 cells and J744A.1 macrophages. Domain analysis identified the rod domain as binding partner of C3. Vimentin was also involved in uptake of C3 as shown by knock down of vimentin in HT22 and J774A.1 cells. The involvement of vimentin in uptake of C3 was further supported by the findings that the vimentin disruptor acrylamide blocked uptake of C3. Vimentin is not only a major organizing element of the intermediate filament network but is also involved in both binding and uptake of C3 exoenzyme. PMID:24967582

  18. Small Spacecraft Technology Initiative (SSTI)

    NASA Technical Reports Server (NTRS)

    Reppucci, George

    1995-01-01

    This is the second in a series of semi-annual reports that describe the technology areas being advanced under this contract and the progress achieved to date. The last technology report concentrated on the spacecraft. This report places greater emphasis on the payloads. White papers by several of the payload providers are attached. These are HSI, UCB, PRKE, and CAFE. This report covers the period from January 1995 through June 1995.

  19. Dense Deposit Disease and C3 Glomerulopathy

    PubMed Central

    Barbour, Thomas D.; Pickering, Matthew C.; Terence Cook, H.

    2013-01-01

    Summary C3 glomerulopathy refers to those renal lesions characterized histologically by predominant C3 accumulation within the glomerulus, and pathogenetically by aberrant regulation of the alternative pathway of complement. Dense deposit disease is distinguished from other forms of C3 glomerulopathy by its characteristic appearance on electron microscopy. The extent to which dense deposit disease also differs from other forms of C3 glomerulopathy in terms of clinical features, natural history, and outcomes of treatment including renal transplantation is less clear. We discuss the pathophysiology of C3 glomerulopathy, with evidence for alternative pathway dysregulation obtained from affected individuals and complement factor H (Cfh)-deficient animal models. Recent linkage studies in familial C3 glomerulopathy have shown genomic rearrangements in the Cfh-related genes, for which the novel pathophysiologic concept of Cfh deregulation has been proposed. PMID:24161036

  20. Histopathology of MPGN and C3 glomerulopathies.

    PubMed

    Cook, H Terence; Pickering, Matthew C

    2015-01-01

    'Membranoproliferative' describes glomerular injury characterized by capillary wall thickening and mesangial expansion owing to increased matrix deposition and hypercellularity. The presence of immune deposits is indicative of membranoproliferative glomerulonephritis (MPGN). Historically, MPGN was further classified into three types according to the appearance and site of the electron-dense deposits seen by electron microscopy, but it is now recognized that many cases show only deposition of the complement component C3, owing to abnormal control of the alternative pathway of complement activation-these cases are now classified as C3 glomerulopathies. Not all cases of C3 glomerulopathy, however, show an MPGN pattern. C3 glomerulopathies include dense deposit disease, which shows dense osmiophilic deposits, and C3 glomerulonephritis, which shows isolated deposits. In many cases, the genetic mutations or autoantibodies responsible for C3 deposition have been identified. Some patients in whom complement control is abnormal will accumulate small amounts of immunoglobulin in their glomeruli and so, in everyday practice, the morphological diagnosis of 'glomerulonephritis with dominant C3' is useful for identifying patients who require investigation of the complement pathway. The recognition that many cases of MPGN are C3 glomerulopathies and that the underlying cause can often be identified in immunoglobulin-associated cases means that the diagnosis of idiopathic MPGN is now very uncommon.

  1. [Complement system regulation and C3 glomerulopathy].

    PubMed

    Xiao, Hui-jie; He, Rui-juan

    2013-04-18

    Complement system is a key system for immune surveillance and homeostasis. Excessive activation of complement system,especially the activation of alternative pathway may play a very important role in the pathogenesis of primary and secondary glomerulonephritis. C3 glomerulopathy is a newly named disease characterized by evident C3 deposition in the glomeruli with little or no immunoglobulin under immunofluorescence (IF). Its clinical and pathological manifestations vary a lot. The decreased plasma C3 and Factor H(FH)suggest that abnormal regulation of complement system plays an importment role in its pathogenesis. C3 glomerulopathy varies a lot as to its clinical manifestation, treatment and prognosis. The inhibition of excessive complement activation might be the key to treating C3 glomerulopathy.

  2. Complement inhibition in C3 glomerulopathy.

    PubMed

    Nester, Carla M; Smith, Richard J H

    2016-06-01

    C3 glomerulopathy (C3G) describes a spectrum of glomerular diseases defined by shared renal biopsy pathology: a predominance of C3 deposition on immunofluorescence with electron microscopy permitting disease sub-classification. Complement dysregulation underlies the observed pathology, a causal relationship that is supported by well described studies of genetic and acquired drivers of disease. In this article, we provide an overview of the features of C3G, including a discussion of disease definition and a review of the causal role of complement. We discuss molecular markers of disease and how biomarkers are informing our evolving understanding of underlying pathology. Research advances are laying the foundation for complement inhibition as a targeted approach to treatment of C3G. PMID:27402056

  3. Eculizumab and Recurrent C3 Glomerulonephritis

    PubMed Central

    Gurkan, Sevgi; Fyfe, Billie; Weiss, Lynne; Xiao, Xue; Zhang, Yuzhou; Smith, Richard J.

    2015-01-01

    Background and objectives Hyperactivity of the alternative complement pathway is the principle defect in the C3 glomerulopathies (C3G). Eculizumab, a monoclonal antibody that binds to C5 to prevent formation of the membrane attack complex, has been shown to be beneficial in some patients with this disease. Design, setting, participants & measurements In this open-label, proof-of-concept efficacy-and-safety study, a patient with the initial diagnosis of Dense Deposit Disease (DDD) and allograft recurrence of C3 (C3GN) glomerulonephritis was treated with eculizumab every-other-week for 1 year. The patient had pathological evidence of C3GN and proteinuria >1 g/d at enrollment. He underwent graft biopsy before enrollment and repeat biopsy at 6 months and 12 months. Results Although no mutations were identified in complement genes, functional studies were positive for C3 nephritic factors and elevated levels of soluble membrane attack complex (sMAC). On therapy, sMAC levels normalized and although proteinuria initially decreased, during therapy it increased reaching pre-treatment levels at 12 months. Although serum creatinine remained stable, repeat allograft biopsies showed progression of disease. Conclusions Clinical and histopathologic data suggest a partial response to eculizumab in this patient. While eculizumab blocked activation of the terminal complement cascade, persistent dysregulation of alternative pathway remained, showing that eculizumab alone cannot control disease in this patient. Additional research is required to identify effective anticomplement therapy for this group of C3G patients. PMID:23689905

  4. C3-class Solar Flare Eruption

    NASA Video Gallery

    Just as sunspot 1105 was turning away from Earth on Sept. 8, the active region erupted, producing a C3-class solar flare (peak @ 2330 UT) and a fantastic prominence. This is a three color closeup o...

  5. 29 CFR 2575.502c-3 - Adjusted civil penalty under section 502(c)(3).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ACT OF 1974 ADJUSTMENT OF CIVIL PENALTIES UNDER ERISA TITLE I Adjustment of Civil Penalties Under ERISA Title I § 2575.502c-3 Adjusted civil penalty under section 502(c)(3). In accordance with the... section 502(c)(3) of the Employee Retirement Income Security Act of 1974, as amended (ERISA), is...

  6. 29 CFR 2575.502c-3 - Adjusted civil penalty under section 502(c)(3).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ACT OF 1974 ADJUSTMENT OF CIVIL PENALTIES UNDER ERISA TITLE I Adjustment of Civil Penalties Under ERISA Title I § 2575.502c-3 Adjusted civil penalty under section 502(c)(3). In accordance with the... section 502(c)(3) of the Employee Retirement Income Security Act of 1974, as amended (ERISA), is...

  7. 29 CFR 2575.502c-3 - Adjusted civil penalty under section 502(c)(3).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ACT OF 1974 ADJUSTMENT OF CIVIL PENALTIES UNDER ERISA TITLE I Adjustment of Civil Penalties Under ERISA Title I § 2575.502c-3 Adjusted civil penalty under section 502(c)(3). In accordance with the... section 502(c)(3) of the Employee Retirement Income Security Act of 1974, as amended (ERISA), is...

  8. 29 CFR 2575.502c-3 - Adjusted civil penalty under section 502(c)(3).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ACT OF 1974 ADJUSTMENT OF CIVIL PENALTIES UNDER ERISA TITLE I Adjustment of Civil Penalties Under ERISA Title I § 2575.502c-3 Adjusted civil penalty under section 502(c)(3). In accordance with the... section 502(c)(3) of the Employee Retirement Income Security Act of 1974, as amended (ERISA), is...

  9. 29 CFR 2575.502c-3 - Adjusted civil penalty under section 502(c)(3).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ACT OF 1974 ADJUSTMENT OF CIVIL PENALTIES UNDER ERISA TITLE I Adjustment of Civil Penalties Under ERISA Title I § 2575.502c-3 Adjusted civil penalty under section 502(c)(3). In accordance with the... section 502(c)(3) of the Employee Retirement Income Security Act of 1974, as amended (ERISA), is...

  10. Rho GTPase Recognition by C3 Exoenzyme Based on C3-RhoA Complex Structure.

    PubMed

    Toda, Akiyuki; Tsurumura, Toshiharu; Yoshida, Toru; Tsumori, Yayoi; Tsuge, Hideaki

    2015-08-01

    C3 exoenzyme is a mono-ADP-ribosyltransferase (ART) that catalyzes transfer of an ADP-ribose moiety from NAD(+) to Rho GTPases. C3 has long been used to study the diverse regulatory functions of Rho GTPases. How C3 recognizes its substrate and how ADP-ribosylation proceeds are still poorly understood. Crystal structures of C3-RhoA complex reveal that C3 recognizes RhoA via the switch I, switch II, and interswitch regions. In C3-RhoA(GTP) and C3-RhoA(GDP), switch I and II adopt the GDP and GTP conformations, respectively, which explains why C3 can ADP-ribosylate both nucleotide forms. Based on structural information, we successfully changed Cdc42 to an active substrate with combined mutations in the C3-Rho GTPase interface. Moreover, the structure reflects the close relationship among Gln-183 in the QXE motif (C3), a modified Asn-41 residue (RhoA) and NC1 of NAD(H), which suggests that C3 is the prototype ART. These structures show directly for the first time that the ARTT loop is the key to target protein recognition, and they also serve to bridge the gaps among independent studies of Rho GTPases and C3.

  11. Genotyping of skin and soft tissue infection (SSTI)-associated methicillin-resistant Staphylococcus aureus (MRSA) strains among outpatients in a teaching hospital in Japan: application of a phage-open reading frame typing (POT) kit.

    PubMed

    Maeda, Tadashi; Saga, Tomoo; Miyazaki, Taito; Kouyama, Yuichi; Harada, Sohei; Iwata, Morihiro; Yoshizawa, Sadako; Kimura, Soichiro; Ishii, Yoshikazu; Urita, Yoshihisa; Sugimoto, Motonobu; Yamaguchi, Keizo; Tateda, Kazuhiro

    2012-12-01

    We aimed to elucidate the current epidemiological features of outpatient skin and soft tissue infection (SSTI)-associated methicillin-resistant Staphylococcus aureus (MRSA) in Japan. Altogether, we evaluated the performance of a phage-open reading frame typing (POT) kit for genotyping these MRSA strains. We collected 57 MRSA strains from all outpatients with SSTIs attending a teaching hospital in Japan. Drug susceptibility measurement and genotyping including SCCmec typing, spa typing, multilocus sequence typing, pulsed-field gel electrophoresis, and commercial POT-kit were performed. The majority of strains (39 strains, 68 %) had the SCCmec-II element. Seventeen strains (30 %) with SCCmec-IV accounted for the second largest population. Strains with SCCmec-IV and SCCmec-V appeared multiclonal, and a predominance of Panton-Valentine leukocidin (PVL) gene-negative CC8/spa-CC008 strains, as well as the first isolate of an ST93 strain in Japan, was observed among them. Only one USA300 strain was identified. Strains with SCCmec-IV and SCCmec-V were significantly susceptible to antimicrobials. The PVL gene was found in 5 SCCmec-IV strains and 1 SCCmec-V strain. The POT-kit successfully predicted the SCCmec type in 54 strains (95 %), and typing by POT1 scores was highly concordant with SCCmec typing and spa typing. Moreover, three PVL-positive strains fell into a particular POT type (POT scores, 106-77-113). Simpson's index of the POT-kit was 0.977. In conclusion, the present study clarified the multiclonal nature of outpatient SSTI-associated MRSA in a teaching hospital in Japan. These data also underscore the utility of the POT-kit for non-outbreak surveillance through its simple platform consisting of two multiplex PCRs without sequencing.

  12. Towards engineering carboxysomes into C3 plants.

    PubMed

    Hanson, Maureen R; Lin, Myat T; Carmo-Silva, A Elizabete; Parry, Martin A J

    2016-07-01

    Photosynthesis in C3 plants is limited by features of the carbon-fixing enzyme Rubisco, which exhibits a low turnover rate and can react with O2 instead of CO2 , leading to photorespiration. In cyanobacteria, bacterial microcompartments, known as carboxysomes, improve the efficiency of photosynthesis by concentrating CO2 near the enzyme Rubisco. Cyanobacterial Rubisco enzymes are faster than those of C3 plants, though they have lower specificity toward CO2 than the land plant enzyme. Replacement of land plant Rubisco by faster bacterial variants with lower CO2 specificity will improve photosynthesis only if a microcompartment capable of concentrating CO2 can also be installed into the chloroplast. We review current information about cyanobacterial microcompartments and carbon-concentrating mechanisms, plant transformation strategies, replacement of Rubisco in a model C3 plant with cyanobacterial Rubisco and progress toward synthesizing a carboxysome in chloroplasts.

  13. Towards engineering carboxysomes into C3 plants.

    PubMed

    Hanson, Maureen R; Lin, Myat T; Carmo-Silva, A Elizabete; Parry, Martin A J

    2016-07-01

    Photosynthesis in C3 plants is limited by features of the carbon-fixing enzyme Rubisco, which exhibits a low turnover rate and can react with O2 instead of CO2 , leading to photorespiration. In cyanobacteria, bacterial microcompartments, known as carboxysomes, improve the efficiency of photosynthesis by concentrating CO2 near the enzyme Rubisco. Cyanobacterial Rubisco enzymes are faster than those of C3 plants, though they have lower specificity toward CO2 than the land plant enzyme. Replacement of land plant Rubisco by faster bacterial variants with lower CO2 specificity will improve photosynthesis only if a microcompartment capable of concentrating CO2 can also be installed into the chloroplast. We review current information about cyanobacterial microcompartments and carbon-concentrating mechanisms, plant transformation strategies, replacement of Rubisco in a model C3 plant with cyanobacterial Rubisco and progress toward synthesizing a carboxysome in chloroplasts. PMID:26867858

  14. Demonstration in human plasma of a form of C3 that has the conformation of "C3b-like C3".

    PubMed

    Hack, C E; Paardekooper, J; Van Milligen, F

    1990-06-01

    Disruption of the thioester in native C3 yields a C3 molecule that functionally resembles C3b. It has been proposed that this C3 molecule (iC3) plays a key role in initiation of the alternative pathway of the C system. However, its presence in plasma has never been demonstrated. We investigated the presence of iC3 in plasma, using mAb that recognize iC3 as well as C3 activation products but not native C3. One of these mAb, anti-C3-5, which binds iC3 via its C3a moiety, was used together with polyclonal 125I-anti-C3c to develop a RIA for iC3. Plasma incubated with methylamine yielded a strong response in this RIA, whereas neither fresh plasma nor serum in which the C system had been activated by incubation with aggregated IgG, did show this strong response. The specificity of this RIA was further demonstrated by additional experiments including experiments with purified preparations of the various forms of C3. Mean level of iC3 in freshly obtained plasma samples from 10 normal donors was 27 nmol/liter, which is 0.49% of total C3. Analysis by SDS-PAGE of C3 species that had been immunoprecipitated by mAb antiC3-5, revealed that some iC3 consisted of C3 molecules with an intact alpha-chain whereas another part consisted of iC3 molecules with an alpha-chain that had been cleaved by factor I. Thus, this study shows that fresh human plasma contains a C3 species with the conformation of "C3b-like C3" (iC3).

  15. Potentiation of NK cytotoxicity by antibody-C3b/iC3b heteroconjugates.

    PubMed

    Yefenof, E; Benizri, R; Reiter, Y; Klein, E; Fishelson, Z

    1990-02-15

    The interaction of two Burkitt lymphoma lines, Raji and Rael, with human C and NK cells was analyzed. Raji cells activate the alternative C pathway (ACP) and then bind C3 fragments. Consequently, the cells become more sensitive to lysis by CR3-bearing NK cells but not to C lysis. In contrast, Rael cells are poor ACP activators, do not bind C3 fragments, and are therefore resistant to C-dependent NK lysis. As suggested earlier, the difference between Raji and Rael could be attributed to the presence or absence of CR2, respectively, on their surface. To potentiate C- and NK-dependent lysis of target cells, we generated heteroconjugates composed of a murine antitransferrin receptor mAb and of human C C3b or iC3b. Antibody-C3b conjugates induced C3 deposition on Rael cells and elevated C3 deposition on Raji cells in human serum. Both Raji and Rael cells coated with antibody-C3b conjugates were efficiently lyzed by the cytolytic ACP in human serum. This conjugate had a small enhancing effect on target cell lysis by NK cells which could be markedly increased by combined treatment of the target cell with antibody-C3b conjugate and C5-depleted human serum. On the other hand, antibody-iC3b conjugates efficiently potentiated lysis of target cells by NK cells in the absence of serum. The iC3b-directed cytotoxicity was mediated by CR3-bearing NK effector cells. Anti-C3 but not anti-mouse Ig antibodies abrogated the activity of the antibody-iC3b conjugate. These results further demonstrate that NK cytotoxicity may be potentiated by opsonizing the target cells with C3 fragments and suggest that antibody-C3b/iC3b conjugates could be potent tools for targeting and potentiation of the lytic action of both C and NK cells against tumor cells.

  16. Potentiation of NK cytotoxicity by antibody-C3b/iC3b heteroconjugates.

    PubMed

    Yefenof, E; Benizri, R; Reiter, Y; Klein, E; Fishelson, Z

    1990-02-15

    The interaction of two Burkitt lymphoma lines, Raji and Rael, with human C and NK cells was analyzed. Raji cells activate the alternative C pathway (ACP) and then bind C3 fragments. Consequently, the cells become more sensitive to lysis by CR3-bearing NK cells but not to C lysis. In contrast, Rael cells are poor ACP activators, do not bind C3 fragments, and are therefore resistant to C-dependent NK lysis. As suggested earlier, the difference between Raji and Rael could be attributed to the presence or absence of CR2, respectively, on their surface. To potentiate C- and NK-dependent lysis of target cells, we generated heteroconjugates composed of a murine antitransferrin receptor mAb and of human C C3b or iC3b. Antibody-C3b conjugates induced C3 deposition on Rael cells and elevated C3 deposition on Raji cells in human serum. Both Raji and Rael cells coated with antibody-C3b conjugates were efficiently lyzed by the cytolytic ACP in human serum. This conjugate had a small enhancing effect on target cell lysis by NK cells which could be markedly increased by combined treatment of the target cell with antibody-C3b conjugate and C5-depleted human serum. On the other hand, antibody-iC3b conjugates efficiently potentiated lysis of target cells by NK cells in the absence of serum. The iC3b-directed cytotoxicity was mediated by CR3-bearing NK effector cells. Anti-C3 but not anti-mouse Ig antibodies abrogated the activity of the antibody-iC3b conjugate. These results further demonstrate that NK cytotoxicity may be potentiated by opsonizing the target cells with C3 fragments and suggest that antibody-C3b/iC3b conjugates could be potent tools for targeting and potentiation of the lytic action of both C and NK cells against tumor cells. PMID:2303717

  17. The Development of the C3 Framework

    ERIC Educational Resources Information Center

    Social Education, 2013

    2013-01-01

    Susan Griffin, executive director of NCSS, was chair of the Task Force of Professional Organizations that initiated and guided the development of "The College, Career, and Civic Life (C3) Framework for Social Studies State Standards", which will soon be released. In this interview with "Social Education", Susan explains how the…

  18. Photosynthesis of C3, C3-C4, and C4 grasses at glacial CO2.

    PubMed

    Pinto, Harshini; Sharwood, Robert E; Tissue, David T; Ghannoum, Oula

    2014-07-01

    Most physiology comparisons of C3 and C4 plants are made under current or elevated concentrations of atmospheric CO2 which do not reflect the low CO2 environment under which C4 photosynthesis has evolved. Accordingly, photosynthetic nitrogen (PNUE) and water (PWUE) use efficiency, and the activity of the photosynthetic carboxylases [Rubisco and phosphoenolpyruvate carboxylase (PEPC)] and decarboxylases [NADP-malic enzyme (NADP-ME) and phosphoenolpyruvate carboxykinase (PEP-CK)] were compared in eight C4 grasses with NAD-ME, PCK, and NADP-ME subtypes, one C3 grass, and one C3-C4 grass grown under ambient (400 μl l(-1)) and glacial (180 μl l(-1)) CO2. Glacial CO2 caused a smaller reduction of photosynthesis and a greater increase of stomatal conductance in C4 relative to C3 and C3-C4 species. Panicum bisulcatum (C3) acclimated to glacial [CO2] by doubling Rubisco activity, while Rubisco was unchanged in Panicum milioides (C3-C4), possibly due to its high leaf N and Rubisco contents. Glacial CO2 up-regulated Rubisco and PEPC activities in concert for several C4 grasses, while NADP-ME and PEP-CK activities were unchanged, reflecting the high control exerted by the carboxylases relative to the decarboxylases on the efficiency of C4 metabolism. Despite having larger stomatal conductance at glacial CO2, C4 species maintained greater PWUE and PNUE relative to C3-C4 and C3 species due to higher photosynthetic rates. Relative to other C4 subtypes, NAD-ME and PEP-CK grasses had the highest PWUE and PNUE, respectively; relative to C3, the C3-C4 grass had higher PWUE and similar PNUE at glacial CO2. Biomass accumulation was reduced by glacial CO2 in the C3 grass relative to the C3-C4 grass, while biomass was less reduced in NAD-ME grasses compared with NADP-ME and PCK grasses. Under glacial CO2, high resource use efficiency offers a key evolutionary advantage for the transition from C3 to C4 photosynthesis in water- and nutrient-limited environments.

  19. A modified competitive inhibition radioimmunoassay for the detection of C3a. Use of 125I-C3 instead of 125I-C3a.

    PubMed

    Hack, C E; Paardekooper, J; Eerenberg, A J; Navis, G O; Nijsten, M W; Thijs, L G; Nuijens, J H

    1988-04-01

    Levels of C3a in plasma are currently measured by a competitive inhibition radioimmunoassay (RIA) in which 125I-C3a is used as a tracer. In this paper, we describe a modification of this RIA: 125I-C3 instead of 125I-C3a is used. The lower limit of detection of this modified RIA is 6 ng of C3a per ml of plasma (i.e. 0.66 nmol/l). This RIA, performed with polyclonal anti-C3a antibodies coupled to a solid phase, appeared to be 30 times more sensitive compared with an RIA in which a monoclonal antibody against C3a is used. In vitro activation of the complement system in serum by aggregated IgG, zymosan, and cobra venom factor resulted in the generation of significant amounts of C3a. Assessment of the C3a levels by the modified RIA in serial plasma samples from patients who underwent cardiopulmonary bypass, yielded results very similar to those described in the literature for the established C3a-RIA. Thus, the modified C3a-RIA offers a convenient alternative for the detection of C3a in plasma samples.

  20. Efficacy of Targeted Complement Inhibition in Experimental C3 Glomerulopathy

    PubMed Central

    Ruseva, Marieta M.; Peng, Tao; Lasaro, Melissa A.; Bouchard, Keith; Liu-Chen, Susan; Sun, Fang; Yu, Zhao-Xue; Marozsan, Andre; Wang, Yi

    2016-01-01

    C3 glomerulopathy refers to renal disorders characterized by abnormal accumulation of C3 within the kidney, commonly along the glomerular basement membrane (GBM). C3 glomerulopathy is associated with complement alternative pathway dysregulation, which includes functional defects in complement regulator factor H (FH). There is no effective treatment for C3 glomerulopathy. We investigated the efficacy of a recombinant mouse protein composed of domains from complement receptor 2 (CR2) and FH (CR2-FH) in two models of C3 glomerulopathy with either preexisting or triggered C3 deposition along the GBM. FH-deficient mice spontaneously develop renal pathology associated with abnormal C3 accumulation along the GBM and secondary plasma C3 deficiency. CR2-FH partially restored plasma C3 levels in FH-deficient mice 2 hours after intravenous injection. CR2-FH specifically targeted glomerular C3 deposits, reduced the linear C3 reactivity assessed with anti-C3 and anti-C3b/iC3b/C3c antibodies, and prevented further spontaneous accumulation of C3 fragments along the GBM. Reduction in glomerular C3d and C9/C5b-9 reactivity was observed after daily administration of CR2-FH for 1 week. In a second mouse model with combined deficiency of FH and complement factor I, CR2-FH prevented de novo C3 deposition along the GBM. These data show that CR2-FH protects the GBM from both spontaneous and triggered C3 deposition in vivo and indicate that this approach should be tested in C3 glomerulopathy. PMID:26047789

  1. Influence of C3 level on the determination of C3d in plasma and synovial fluid by radial immunodiffusion.

    PubMed

    Hack, C E; Paardekooper, J; Hannema, A J

    1986-02-12

    The influence of C3 levels on the determination of C3d in plasma and synovial fluid by radial immunodiffusion was investigated. In the method used, C3 is precipitated by 11% polyethylene glycol (PEG), and C3d is measured in the supernatant. In 51 healthy donors, a weak though significant correlation between C3 and C3d levels was found. The mean concentration of C3d was 1.6% of that in aged serum from healthy donors. So, small amounts of C3 (i.e., 1-2% of the normal plasma level) in the 11% PEG supernatants may contribute significantly to the C3d levels measured. A radioimmunoassay that detects C3, C3b, iC3b and C3c was used to measure C3 levels in the PEG supernatants. In PEG supernatants of 4 plasma samples, 0.3-0.6% of the C3 level in normal plasma was found, whereas in those of 2 synovial fluids much higher levels were found (4-10% of the normal plasma level). When purified 125I-labeled antibodies against C3c were added to the gel of the radial immunodiffusion, C3c antigen was detected in the precipitation rings obtained with all PEG supernatants of plasma samples from patients. Therefore, the quantitative contribution of C3 to the precipitation rings in the C3d radial immunodiffusion was analyzed after the addition of an excess of anti-C3c antibodies to the gel. No effect on the size of the C3d-precipitation rings obtained with plasma samples from patients was observed. However, the C3d precipitation rings obtained with synovial fluids were significantly smaller when the gel used in the radial immunodiffusion contained an excess of anti-C3c antibodies together with the anti-C3d serum. We conclude that it is necessary to add an excess of anti-C3c antibodies to the gel used for the radial immunodiffusion, for the determination of C3d levels in synovial fluid. An antiserum against human C3b, which contains both anti-C3c and anti-C3d antibodies, can be used for this purpose.

  2. Geminivirus C3 Protein: Replication Enhancement and Protein Interactions

    PubMed Central

    Settlage, Sharon B.; See, Renee G.; Hanley-Bowdoin, Linda

    2005-01-01

    Most dicot-infecting geminiviruses encode a replication enhancer protein (C3, AL3, or REn) that is required for optimal replication of their small, single-stranded DNA genomes. C3 interacts with C1, the essential viral replication protein that initiates rolling circle replication. C3 also homo-oligomerizes and interacts with at least two host-encoded proteins, proliferating cell nuclear antigen (PCNA) and the retinoblastoma-related protein (pRBR). It has been proposed that protein interactions contribute to C3 function. Using the C3 protein of Tomato yellow leaf curl virus, we examined the impact of mutations to amino acids that are conserved across the C3 protein family on replication enhancement and protein interactions. Surprisingly, many of the mutations did not affect replication enhancement activity of C3 in tobacco protoplasts. Other mutations either enhanced or were detrimental to C3 replication activity. Analysis of mutated proteins in yeast two-hybrid assays indicated that mutations that inactivate C3 replication enhancement activity also reduce or inactivate C3 oligomerization and interaction with C1 and PCNA. In contrast, mutated C3 proteins impaired for pRBR binding are fully functional in replication assays. Hydrophobic residues in the middle of the C3 protein were implicated in C3 interaction with itself, C1, and PCNA, while polar resides at both the N and C termini of the protein are important for C3-pRBR interaction. These experiments established the importance of C3-C3, C3-C1, and C3-PCNA interactions in geminivirus replication. While C3-pRBR interaction is not required for viral replication in cycling cells, it may play a role during infection of differentiated cells in intact plants. PMID:16014949

  3. Step 1: C3 Flight Demo Data Analysis Plan

    NASA Technical Reports Server (NTRS)

    2005-01-01

    The Data Analysis Plan (DAP) describes the data analysis that the C3 Work Package (WP) will perform in support of the Access 5 Step 1 C3 flight demonstration objectives as well as the processes that will be used by the Flight IPT to gather and distribute the data collected to satisfy those objectives. In addition to C3 requirements, this document will encompass some Human Systems Interface (HSI) requirements in performing the C3 flight demonstrations. The C3 DAP will be used as the primary interface requirements document between the C3 Work Package and Flight Test organizations (Flight IPT and Non-Access 5 Flight Programs). In addition to providing data requirements for Access 5 flight test (piggyback technology demonstration flights, dedicated C3 technology demonstration flights, and Airspace Operations Demonstration flights), the C3 DAP will be used to request flight data from Non- Access 5 flight programs for C3 related data products

  4. Interplay between invertebrate C3a with vertebrate macrophages: functional characterization of immune activities of amphioxus C3a.

    PubMed

    Gao, Zhan; Li, Mengyang; Wu, Jie; Zhang, Shicui

    2013-10-01

    Our current knowledge of the structure and function of C3a comes from the study of vertebrate C3a anaphylatoxins, virtually nothing is known about the structure and function of C3a molecules in invertebrates. Here we demonstrated that C3a from the invertebrate chordate Branchiostoma japonicum, BjC3a, was similar to vertebrate C3a possessing potential antibacterial activity, as revealed by sequence analysis and computational modeling. The antibacterial activity of BjC3a was definitely confirmed by both antibacterial assay and TEM observation showing that recombinant BjC3a was directly bactericidal. Additionally, recombinant BjC3a, like vertebrate C3a, was capable of inducing sea bass macrophage migration and enhancing macrophage phagocytosis and respiratory burst response. Moreover, recombinant BjC3a-desArg (generated by removal of the C-terminal arginine), like mammalian C3a-desArg, retained the immunological activities of BjC3a such as antibacterial and respiratory burst-stimulating activities, indicating that the immunological functions of C3a-desArg were conserved throughout chordate evolution. Altogether, our findings show that invertebrate (amphioxus) BjC3a is able to interact with vertebrate (sea bass) macrophages and mediate immune activities, suggesting the emergence of the inflammatory pathway of the complement system similar to that of vertebrates in the basal chordate amphioxus.

  5. Interplay between invertebrate C3a with vertebrate macrophages: functional characterization of immune activities of amphioxus C3a.

    PubMed

    Gao, Zhan; Li, Mengyang; Wu, Jie; Zhang, Shicui

    2013-10-01

    Our current knowledge of the structure and function of C3a comes from the study of vertebrate C3a anaphylatoxins, virtually nothing is known about the structure and function of C3a molecules in invertebrates. Here we demonstrated that C3a from the invertebrate chordate Branchiostoma japonicum, BjC3a, was similar to vertebrate C3a possessing potential antibacterial activity, as revealed by sequence analysis and computational modeling. The antibacterial activity of BjC3a was definitely confirmed by both antibacterial assay and TEM observation showing that recombinant BjC3a was directly bactericidal. Additionally, recombinant BjC3a, like vertebrate C3a, was capable of inducing sea bass macrophage migration and enhancing macrophage phagocytosis and respiratory burst response. Moreover, recombinant BjC3a-desArg (generated by removal of the C-terminal arginine), like mammalian C3a-desArg, retained the immunological activities of BjC3a such as antibacterial and respiratory burst-stimulating activities, indicating that the immunological functions of C3a-desArg were conserved throughout chordate evolution. Altogether, our findings show that invertebrate (amphioxus) BjC3a is able to interact with vertebrate (sea bass) macrophages and mediate immune activities, suggesting the emergence of the inflammatory pathway of the complement system similar to that of vertebrates in the basal chordate amphioxus. PMID:23954696

  6. Glycine decarboxylase in C3, C4 and C3-C4 intermediate species.

    PubMed

    Schulze, Stefanie; Westhoff, Peter; Gowik, Udo

    2016-06-01

    The glycine decarboxylase complex (GDC) plays a central role in photorespiration. GDC is localized in the mitochondria and together with serine hydroxymethyltransferase it converts two molecules of glycine to one molecule of serine, CO2 and NH3. Overexpression of GDC subunits in the C3 species Arabidopsis thaliana can increase the metabolic flux through the photorespiratory pathway leading to enhanced photosynthetic efficiency and consequently to an enhanced biomass production of the transgenic plants. Changing the spatial expression patterns of GDC subunits was an important step during the evolution of C3-C4 intermediate and likely also C4 plants. Restriction of the GDC activity to the bundle sheath cells led to the establishment of a photorespiratory CO2 pump. PMID:27038285

  7. On the Y-chromosome haplogroup C3c classification.

    PubMed

    Malyarchuk, Boris A; Derenko, Miroslava; Denisova, Galina

    2012-10-01

    As there are ambiguities in classification of the Y-chromosome haplogroup C3c, relatively frequent in populations of Northern Asia, we analyzed all three haplogroup-defining markers M48, M77 and M86 in C3-M217-individuals from Siberia, Eastern Asia and Eastern Europe. We have found that haplogroup C3c is characterized by the derived state at M48, whereas mutations at both M77 and M86 define subhaplogroup C3c1. The branch defined by M48 alone would belong to subhaplogroup C3c*, characteristic for some populations of Central and Eastern Siberia, such as Koryaks, Evens, Evenks and Yukaghirs. Subhaplogroup C3c* individuals could be considered as remnants of the Neolithic population of Siberia, based on the age of C3c*-short tandem repeat variation amounting to 4.5 ± 2.4 thousand years. PMID:22810113

  8. The complement fragment C3d facilitates phagocytosis by monocytes.

    PubMed

    Gaither, T A; Vargas, I; Inada, S; Frank, M M

    1987-11-01

    Two receptors for fragments of C3 are described for human monocytes: CR1 and CR3, which bind C3b and iC3b, respectively. Recently a leucocyte receptor that binds C3dg has also been described, designated CR4. We previously reported that IgM-sensitized sheep erythrocytes that are heavily coated with C3d (EAC3d) can bind to human monocytes that have been cultured in fetal calf serum (FCS). Here we determine whether such binding of C3d-coated targets can lead to phagocytosis, and identify the specific monocyte receptor involved in C3d binding. We confirm that EAC3d bearing greater than 10,000 C3d/cell bind to FCS-cultured monocytes. Furthermore, using non-cultured monocytes, we demonstrate that C3d enhances rosette formation of IgG-coated E and, like C3b and iC3b, C3d augments IgG Fc receptor-mediated phagocytosis. Less than 100 C3d/cell are capable of enhancing phagocytosis, whereas 10,000 or more C3d/cell are required for rosette formation with cultured cells. These results indicate that the C3d-binding receptor is present on peripheral blood monocytes but has poor affinity for target particles coated only with C3d. Anti-CR2 monoclonal antibodies, which recognize the C3d receptor of lymphocytes, do not block EAC3d rosette formation with monocytes. In contrast anti-Mol, a monoclonal antibody against CR3, inhibits EAC3d rosettes by approximately 42%. Anti-CR1 increases this effect, but complete inhibition is not achieved. Ethylenediamine tetraacetate also markedly reduces EAC3d rosetting, reducing the numbers to less than 5%. Thus, the C3d-binding receptor on monocytes, unlike CR4, is metal dependent. Together these data indicate that CR3 is predominantly responsible for C3d binding to monocytes. PMID:3499379

  9. Photosynthesis, Leaf Anatomy, and Morphology of Progeny from Hybrids between C(3) and C(3)/C(4)Panicum Species.

    PubMed

    Bouton, J H; Brown, R H; Evans, P T; Jernstedt, J A

    1986-02-01

    Species in the Laxa group of Panicum have C(3) or C(3)/C(4) photosynthesis based on leaf anatomical and CO(2) exchange characteristics. Hybrids were previously made between C(3)/C(4) and C(3) species in this group (RH Brown et al. 1985 Plant Physiol 77: 653-658). In this paper, CO(2) exchange, morphological, and leaf anatomical characteristics of F(2) or F(5) progeny from colchicine-induced amphiploids of C(3)/C(4) x C(3) hybrids (Panicum milioides Nees ex Trin. [C(3)/C(4)] x Panicum laxum Mez [C(3)] and Panicum spathellosum Doell [C(3)/C(4)] x Panicum boliviense Hack. [C(3)]) were studied.There were no differences found in morphology or physiology between the amphiploids and the F(1) hybrids from which they were produced. In the segregating progeny, CO(2) compensation concentration and photorespiration values typical of C(3), but not of C(3)/C(4) plants, were recovered. Progeny were found from both crosses which possessed O(2) inhibition of apparent photosynthesis typical of the parents, and in the case of the P. milioides x P. laxum cross, leaf anatomy and overall plant morphology typical of the parents were observed in some progeny. The progeny were found to possess recombinations of various traits associated with reduced photorespiration, so that no correlation existed among O(2) inhibition of apparent photosynthesis, CO(2) compensation concentration, and leaf anatomical traits. One plant was especially noteworthy in possessing leaf anatomy typical of C(3)/C(4) plants, but with CO(2) exchange characteristics of C(3) plants.

  10. Why Are C3-C4 Intermediate Species Rare?

    NASA Astrophysics Data System (ADS)

    Johnson, J. E.; Field, C. B.; Berry, J. A.

    2014-12-01

    While C3-C4 intermediate photosynthesis is thought to represent the evolutionary bridge between C3 and C4 photosynthesis, C3-C4 intermediate species are ecologically rare in comparison to both C3 and C4 species. Here, we report results from a laboratory experiment, field observations, and model simulations that suggest a new explanation for the ecological rarity of C3-C4 intermediate species. In the laboratory experiment, we combined gas exchange and fluorescence to characterize the temperature response of photosynthesis in three closely-related species in the genus Flaveria that are representatives of the C3, C3-C4 intermediate, and C4 photosynthetic pathways. The leaf temperature that maximized the quantum yield for CO2 assimilation (Topt(ΦCO2)) was 24.9 ± 0.7°C in Flaveria robusta (C3), 29.8 ± 1.0°C in F. chloraefolia (C3-C4), and 35.7 ± 0.8°C in F. bidentis (C4), and was linearly related to the temperature sensitivity of the coupling between CO2 assimilation and electron transport (d(ΦCO2/ ΦPSII)/dT)). While F. chloraefolia does not simultaneously occur with F. robusta and F. bidentis in naturally-assembled communities, this C3-C4 intermediate species does occur with other C3 and C4 species. During the growing season in two of these mixed-photosynthetic-type communities, leaf temperatures for F. chloraefolia were similar to the Topt(ΦCO2) determined in the laboratory. A model of maximum potential carbon gain suggests that competitive coexistence of C3, C3-C4 intermediate, and C4 species could be dependent on a temperature regime that highlights the distinct relative advantages of the C3-C4 intermediate pathway. In combination, these results suggest that the relative temperature sensitivity of the C3, C3-C4 intermediate, and C4 photosynthetic pathways combined with environmental variation in temperature may help to explain why C3-C4 intermediate species are generally rare.

  11. The molecular and structural bases for the association of complement C3 mutations with atypical hemolytic uremic syndrome.

    PubMed

    Martínez-Barricarte, Rubén; Heurich, Meike; López-Perrote, Andrés; Tortajada, Agustin; Pinto, Sheila; López-Trascasa, Margarita; Sánchez-Corral, Pilar; Morgan, B Paul; Llorca, Oscar; Harris, Claire L; Rodríguez de Córdoba, Santiago

    2015-08-01

    Atypical hemolytic uremic syndrome (aHUS) associates with complement dysregulation caused by mutations and polymorphisms in complement activators and regulators. However, the reasons why some mutations in complement proteins predispose to aHUS are poorly understood. Here, we have investigated the functional consequences of three aHUS-associated mutations in C3, R592W, R161W and I1157T. First, we provide evidence that penetrance and disease severity for these mutations is modulated by inheritance of documented "risk" haplotypes as has been observed with mutations in other complement genes. Next, we show that all three mutations markedly reduce the efficiency of factor I-mediated C3b cleavage when catalyzed by membrane cofactor protein (MCP), but not when catalyzed by factor H. Biacore analysis showed that each mutant C3b bound sMCP (recombinant soluble MCP; CD46) at reduced affinity, providing a molecular basis for its reduced cofactor activity. Lastly, we show by electron microscopy structural analysis a displacement of the TED domain from the MG ring in C3b in two of the C3 mutants that explains these defects in regulation. As a whole our data suggest that aHUS-associated mutations in C3 selectively affect regulation of complement on surfaces and provide a structural framework to predict the functional consequences of the C3 genetic variants found in patients.

  12. The molecular and structural bases for the association of complement C3 mutations with atypical hemolytic uremic syndrome

    PubMed Central

    Martínez-Barricarte, Rubén; Heurich, Meike; López-Perrote, Andrés; Tortajada, Agustin; Pinto, Sheila; López-Trascasa, Margarita; Sánchez-Corral, Pilar; Morgan, B. Paul; Llorca, Oscar; Harris, Claire L.; Rodríguez de Córdoba, Santiago

    2015-01-01

    Atypical hemolytic uremic syndrome (aHUS) associates with complement dysregulation caused by mutations and polymorphisms in complement activators and regulators. However, the reasons why some mutations in complement proteins predispose to aHUS are poorly understood. Here, we have investigated the functional consequences of three aHUS-associated mutations in C3, R592W, R161W and I1157T. First, we provide evidence that penetrance and disease severity for these mutations is modulated by inheritance of documented “risk” haplotypes as has been observed with mutations in other complement genes. Next, we show that all three mutations markedly reduce the efficiency of factor I-mediated C3b cleavage when catalyzed by membrane cofactor protein (MCP), but not when catalyzed by factor H. Biacore analysis showed that each mutant C3b bound sMCP (recombinant soluble MCP; CD46) at reduced affinity, providing a molecular basis for its reduced cofactor activity. Lastly, we show by electron microscopy structural analysis a displacement of the TED domain from the MG ring in C3b in two of the C3 mutants that explains these defects in regulation. As a whole our data suggest that aHUS-associated mutations in C3 selectively affect regulation of complement on surfaces and provide a structural framework to predict the functional consequences of the C3 genetic variants found in patients. PMID:25879158

  13. A study of C3HD in cold interstellar clouds.

    PubMed

    Bell, M B; Avery, L W; Matthews, H E; Feldman, P A; Watson, J K; Madden, S C; Irvine, W M

    1988-03-15

    We have detected the 1(10)-1(01) transition of C3HD at 19.418 GHz at twelve positions in cold, dark clouds and resolved the D hyperfine components in two sources (L1498 and TMC-1C) well enough to derive values for the D quadrupole coupling constants. Simultaneous observations of C3H2 in each source yield relative integrated line intensities in the range 0.10-0.18, from which we derive relative [C3HD]/[C3H2] abundances in the range 0.05-0.15. These are among the highest deuteration ratios yet observed. Within the limits of the observational and modeling uncertainties it is possible to explain the derived [C3HD]/[C3H2] ratios by ion-molecule chemistry if [e-] approximately 3 x 10(-7).

  14. Intracellular sensing of complement C3 activates cell autonomous immunity

    PubMed Central

    Tam, Jerry C.H.; Bidgood, Susanna R.; McEwan, William A.; James, Leo C.

    2014-01-01

    Pathogens traverse multiple barriers during infection including cell membranes. Here we show that during this transition pathogens carry covalently attached complement C3 into the cell, triggering immediate signalling and effector responses. Sensing of C3 in the cytosol activates MAVS-dependent signalling cascades and induces proinflammatory cytokine secretion. C3 also flags viruses for rapid proteasomal degradation, thereby preventing their replication. This system can detect both viral and bacterial pathogens but is antagonized by enteroviruses, such as rhinovirus and poliovirus, which cleave C3 using their 3C protease. The antiviral Rupintrivir inhibits 3C protease and prevents C3 cleavage, rendering enteroviruses susceptible to intracellular complement sensing. Thus, complement C3 allows cells to detect and disable pathogens that have invaded the cytosol. PMID:25190799

  15. Bladder cancer risk and genetic variation in AKR1C3 and other metabolizing genes

    PubMed Central

    Figueroa, Jonine D.; Malats, Núria; García-Closas, Montserrat; Real, Francisco X.; Silverman, Debra; Kogevinas, Manolis; Chanock, Stephen; Welch, Robert; Dosemeci, Mustafa; Lan, Qing; Tardón, Adonina; Serra, Consol; Carrato, Alfredo; García-Closas, Reina; Castaño-Vinyals, Gemma; Rothman, Nathaniel

    2008-01-01

    Aromatic amines (AAs) and polycyclic aromatic hydrocarbons (PAHs) are carcinogens present in tobacco smoke and functional polymorphisms in NAT2 and GSTM1 metabolizing genes are associated with increased bladder cancer risk. We evaluated whether genetic variation in other candidate metabolizing genes are also associated with risk. Candidates included genes that control the transcription of metabolizing genes [aryl hydrocarbon receptor (AHR), AHRR and aryl hydrocarbon nuclear translocator (ARNT)] and genes that activate/detoxify AA or PAH (AKR1C3, CYP1A1, CYP1A2, CYP1B1, CYP3A4, EPHX1, EPHX2, NQO1, MPO, UGT1A4, SULT1A1 and SULT1A2). Using genotype data from 1150 cases of urothelial carcinomas and 1149 controls from the Spanish Bladder Cancer Study, we estimated odds ratios (ORs) and 95% confidence intervals (CIs) adjusting for age, gender, region and smoking status. Based on a test for trend, we observed 10 non-redundant single-nucleotide polymorphisms (SNPs) in five genes (AKR1C3, ARNT, CYP1A1, CYP1B1 and SULT1A2) significantly associated with bladder cancer risk. We observed an inverse association with risk for the AKR1C3 promoter SNP rs1937845 [OR (95% CI) for heterozygote and homozygote variant compared with common homozygote genotype were 0.86 (0.70–1.06) and 0.74 (0.57–0.96), respectively; P for trend = 0.02]. Interestingly, genetic variation in this region has been associated with lung, non-Hodgkin lymphoma and prostate cancer risk. Analysis of additional SNPs to capture most (∼90%) of common genetic variation in AKR1C3 and haplotype walking analyses based on all AKR1C3 SNPs (n = 25) suggest two separate regions associated with bladder cancer risk. These results indicate that genetic variation in carcinogen-metabolizing genes, particularly AKR1C3, could be associated with bladder cancer risk. PMID:18632753

  16. Platelet-associated complement C3 in immune thrombocytopenic purpura

    SciTech Connect

    Myers, T.J.; Kim, B.K.; Steiner, M.; Baldini, M.G.

    1982-05-01

    Platelet-associated C3 (PA-C3) was measured with a quantitative immunofluorescence assay. With this assay, PA-C3 levels were determined for 78 normal volunteers, 30 patients with immune thrombocytopenic purpura (ITP), and 20 patients with nonimmune thrombocytopenias. Platelet-associatd IgG (PA-lgG) levels were also measured with our standard quantitative immunofluorescence assay. All patients with nonimmune thrombocytopenias and ITP in remission had normal PA-C3 levels. Twenty-four patients with active ITP wre classified into 3 groups: 9 (38%) with increased PA-IgG and normal PA-C3 levels, 10 (42%) with elevated PA-C3 and PA-IgG levels, and 5 (20%) with increased PA-C3 values only. A direct correlation was found between PA-C3 and PA-IgG levels. PA-IgG levels were higher in the group of patients with elevated PA-C3 levels than in those with normal values. Platelet survival studies showed reduced survival times of 1.5-2.5 days for the 5 patients with elevated PA-C3 levels only. Elevated PA-C3 levels returned to normal in 7 ITP patients whose platelet counts increased in response to corticosteriod therapy or to splenectomy. Therefore, PA-C3 and PA-IgG assays can be used to identify patients with ITP, to follow their response to therapy, and to classify them into immunologic subgroups similar to red cell classifiation by Coombs' testing in immune hemolytic anemia.

  17. Fibronectin and serum amyloid P component stimulate C3b- and C3bi- mediated phagocytosis in cultured human monocytes

    PubMed Central

    1983-01-01

    Fibronectin (FN) and serum amyloid P component (SAP) markedly enhance phagocytosis mediated by the C3b and C3bi receptors of cultured human monocytes but not of granulocytes. (The C3b and C3bi receptors of granulocytes can be activated by treatment of these phagocytes with PMA.) Activation of monocyte C3 receptors by FN is developmentally regulated: Freshly explanted monocytes respond to FN with a small increase in C3 receptor-mediated phagocytosis while monocytes matured in culture exhibit a much greater response. The mechanism of action of FN on C3 receptors of cultured monocytes is unique in two respects. First, while substrate-bound FN or SAP activate monocyte C3 receptors, soluble FN does not. Second, stimulation of the basal surface of monocyte plasma membranes by substrate-bound FN activates C3b and C3bi receptors on the apical surface of the plasma membrane, i.e., at sites remote from the segments of membrane in contact with the FN or SAP. PMID:6225825

  18. 42 CFR 68c.3 - Who is eligible to apply?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Who is eligible to apply? 68c.3 Section 68c.3 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES FELLOWSHIPS, INTERNSHIPS, TRAINING NATIONAL INSTITUTE OF CHILD HEALTH AND HUMAN DEVELOPMENT CONTRACEPTION AND INFERTILITY...

  19. 42 CFR 68c.3 - Who is eligible to apply?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Who is eligible to apply? 68c.3 Section 68c.3 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES FELLOWSHIPS, INTERNSHIPS, TRAINING NATIONAL INSTITUTE OF CHILD HEALTH AND HUMAN DEVELOPMENT CONTRACEPTION AND INFERTILITY...

  20. 42 CFR 68c.3 - Who is eligible to apply?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Who is eligible to apply? 68c.3 Section 68c.3 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES FELLOWSHIPS, INTERNSHIPS, TRAINING NATIONAL INSTITUTE OF CHILD HEALTH AND HUMAN DEVELOPMENT CONTRACEPTION AND INFERTILITY...

  1. Thermal stability of the polyheme cytochrome c3 superfamily.

    PubMed

    Florens, L; Bianco, P; Haladjian, J; Bruschi, M; Protasevich, I; Makarov, A

    1995-10-16

    The cytochrome c3 superfamily includes Desulfovibrio polyheme cytochromes c. We report the characteristic thermal stability parameters of the Desulfovibrio desulfuricans Norway (D.d.N.) cytochromes c3 (M(r) 13,000 and M(r) 26,000) and the Desulfovibrio vulgaris Hildenborough (D.v.H.) cytochrome c3 (M(r) 13,000) and high molecular mass cytochrome c (Hmc), as obtained with the help of electronic spectroscopy, voltammetric techniques and differential scanning calorimetry. The polyheme cytochromes are denatured over a wide range of temperatures: the D.v.H. cytochrome c3 is highly thermostable (Td = 121 degrees C) contrary to the D.d.N. protein (Td = 73 degrees C). The thermostability of the polyheme cytochromes is redox state dependent. The results are discussed in the light of the structural and functional relationships within the cytochrome c3 superfamily. PMID:7589483

  2. Photosynthesis, Morphology, Leaf Anatomy, and Cytogenetics of Hybrids between C(3) and C(3)/C(4)Panicum Species.

    PubMed

    Brown, R H; Bouton, J H; Evans, P T; Malter, H E; Rigsby, L L

    1985-03-01

    The Laxa group of the Panicum genus contains species which have CO(2) exchange and anatomical characteristics intermediate to C(3) and C(4) photosynthetic types (C(3)/C(4)), and also species characterized as C(3). Hybrids were made between two of the C(3)/C(4) species and two C(3) species. Carbon dioxide exchange and morphological, leaf anatomical, and cytogenetic characteristics of F(1) hybrids between Panicum milioides Nees. ex Trin (C(3)/C(4)) and P. laxum Mez. (C(3)), P. spathellosum Doell (C(3)/C(4)) and P. boliviense Hack. (C(3)), and P. spathellosum and P. laxum were studied. There were no consistent differences in apparent photosynthesis, although two of the three hybrids had higher net CO(2) uptake than the C(3) parent. Values of inhibition of apparent photosynthesis by 21% O(2), CO(2) loss in the light, and CO(2) compensation concentration for the hybrids were between those of the parents. All three hybrids showed leaf anatomical traits, especially organelle quantities in the bundle sheath cells, between those of their respective parents. Linear regression of CO(2) compensation concentration on the percentage of mitochondria and chloroplasts in vascular bundle sheaths of the parents and hybrids gave correlation coefficients of -0.94. This suggests that the reduction in CO(2) loss in the C(3)/C(4) species, and to a lesser degree in the F(1) hybrids, was due to development of organelles and perhaps a higher proportion of leaf photorespiration in bundle sheaths. The overall morphology of the hybrids was so different from the parents that they could be described as new taxonomic forms. The chromosomes in the hybrids were mainly unpaired or paired as bivalents indicating possible homology between some parental genomes.

  3. Stereochemistry analysis and comparison of two C(3)-alkyl substituted cyclohexonedicarboxylates with their C(3)-aryl substituted analogues

    NASA Astrophysics Data System (ADS)

    Chen, Chao-Yue; Wang, Qi; Zhu, Bing-Long; Zhao, Wen-Jie; Hu, Jin-Song

    2016-03-01

    Two representative C(3)-alkyl substituted cyclohexonedicarboxylates (4a and 4b) were synthesized and their conformational features were investigated by single crystal X-ray crystallography for the first time. These stereochemistry results of 4a and 4b were compared with those obtained from the earlier research of C(3)-aryl substituted analogues (1-3).

  4. Reduction of uranium by cytochrome c3 of Desulfovibrio vulgaris

    USGS Publications Warehouse

    Lovley, D.R.; Widman, P.K.; Woodward, J.C.; Phillips, E.J.P.

    1993-01-01

    The mechanism for U(VI) reduction by Desulfovibrio vulgaris (Hildenborough) was investigated. The H2-dependent U(VI) reductase activity in the soluble fraction of the cells was lost when the soluble fraction was passed over a cationic exchange column which extracted cytochrome c3. Addition of cytochrome c3 back to the soluble fraction that had been passed over the cationic exchange column restored the U(VI)-reducing capacity. Reduced cytochrome c3 was oxidized by U(VI), as was a c-type cytochrome(s) in whole-cell suspensions. When cytochrome c3 was combined with hydrogenase, its physiological electron donor, U(VI) was reduced in the presence of H2. Hydrogenase alone could not reduce U(VI). Rapid U(VI) reduction was followed by a subsequent slow precipitation of the U(IV) mineral uraninite. Cytochrome c3 reduced U(VI) in a uranium-contaminated surface water and groundwater. Cytochrome c3 provides the first enzyme model for the reduction and biomineralization of uranium in sedimentary environments. Furthermore, the finding that cytochrome c3 can catalyze the reductive precipitation of uranium may aid in the development of fixed-enzyme reactors and/or organisms with enhanced U(VI)-reducing capacity for the bioremediation of uranium- contaminated waters and waste streams.

  5. Reduction of uranium by cytochrome c3 of Desulfovibrio vulgaris.

    PubMed

    Lovley, D R; Widman, P K; Woodward, J C; Phillips, E J

    1993-11-01

    The mechanism for U(VI) reduction by Desulfovibrio vulgaris (Hildenborough) was investigated. The H2-dependent U(VI) reductase activity in the soluble fraction of the cells was lost when the soluble fraction was passed over a cationic exchange column which extracted cytochrome c3. Addition of cytochrome c3 back to the soluble fraction that had been passed over the cationic exchange column restored the U(VI)-reducing capacity. Reduced cytochrome c3 was oxidized by U(VI), as was a c-type cytochrome(s) in whole-cell suspensions. When cytochrome c3 was combined with hydrogenase, its physiological electron donor, U(VI) was reduced in the presence of H2. Hydrogenase alone could not reduce U(VI). Rapid U(VI) reduction was followed by a subsequent slow precipitation of the U(IV) mineral uraninite. Cytochrome c3 reduced U(VI) in a uranium-contaminated surface water and groundwater. Cytochrome c3 provides the first enzyme model for the reduction and biomineralization of uranium in sedimentary environments. Furthermore, the finding that cytochrome c3 can catalyze the reductive precipitation of uranium may aid in the development of fixed-enzyme reactors and/or organisms with enhanced U(VI)-reducing capacity for the bioremediation of uranium-contaminated waters and waste streams.

  6. Electrostatic Steering Accelerates C3d:CR2 Association.

    PubMed

    Mohan, Rohith R; Huber, Gary A; Morikis, Dimitrios

    2016-08-25

    Electrostatic effects are ubiquitous in protein interactions and are found to be pervasive in the complement system as well. The interaction between complement fragment C3d and complement receptor 2 (CR2) has evolved to become a link between innate and adaptive immunity. Electrostatic interactions have been suggested to be the driving factor for the association of the C3d:CR2 complex. In this study, we investigate the effects of ionic strength and mutagenesis on the association of C3d:CR2 through Brownian dynamics simulations. We demonstrate that the formation of the C3d:CR2 complex is ionic strength-dependent, suggesting the presence of long-range electrostatic steering that accelerates the complex formation. Electrostatic steering occurs through the interaction of an acidic surface patch in C3d and the positively charged CR2 and is supported by the effects of mutations within the acidic patch of C3d that slow or diminish association. Our data are in agreement with previous experimental mutagenesis and binding studies and computational studies. Although the C3d acidic patch may be locally destabilizing because of unfavorable Coulombic interactions of like charges, it contributes to the acceleration of association. Therefore, acceleration of function through electrostatic steering takes precedence to stability. The site of interaction between C3d and CR2 has been the target for delivery of CR2-bound nanoparticle, antibody, and small molecule biomarkers, as well as potential therapeutics. A detailed knowledge of the physicochemical basis of C3d:CR2 association may be necessary to accelerate biomarker and drug discovery efforts. PMID:27092816

  7. C3d adjuvant effects are mediated through the activation of C3d-specific autoreactive T cells.

    PubMed

    De Groot, Anne S; Ross, Ted M; Levitz, Lauren; Messitt, Timothy J; Tassone, Ryan; Boyle, Christine M; Vincelli, Amber J; Moise, Leonard; Martin, William; Knopf, Paul M

    2015-02-01

    Complement fragment C3d covalently attached to antigens enhances immune responses, particularly for antigens lacking T-cell epitopes. Enhancement has been attributed to receptor cross-linking between complement receptor CR2 (CD21) and polysaccharide antigen to surface IgM on naïve B cells. Paradoxically, C3d has still been shown to increase immune responses in CD21 knockout mice, suggesting that an auxiliary activation pathway exists. In prior studies, we demonstrated the CD21-independent C3d adjuvant effect might be due to T-cell recognition of C3d T-helper epitopes processed and presented by major histocompatibility complex class II on the B-cell surface. C3d peptide sequences containing concentrated clusters of putative human C3 T-cell epitopes were identified using the epitope-mapping algorithm, EpiMatrix. These peptide sequences were synthesized and shown in vitro to bind multiple human leukocyte antigen (HLA)-DR alleles with high affinity, and induce interferon-γ responses in healthy donor peripheral blood mononuclear cells. In the present studies, we establish further correlations between HLA binding and HLA-specific lymphocyte reactions with select epitope clusters. In addition, we show that the T-cell phenotype of C3d-specific reactive T cells is CD4(+)CD45RO(+) memory T cells. Finally, mutation of a single T-cell epitope residing within the P28 peptide segment of C3d resulted in significantly diminished adjuvant activity in BALB/c mice. Collectively, these studies support the hypothesis that the paradoxical enhancement of immune responses by C3d in the absence of CD21 is due to internalization and processing of C3d into peptides that activate autoreactive CD4(+) T-helper cells in the context of HLA class II.

  8. C3d adjuvant effects are mediated through the activation of C3d-specific autoreactive T cells.

    PubMed

    De Groot, Anne S; Ross, Ted M; Levitz, Lauren; Messitt, Timothy J; Tassone, Ryan; Boyle, Christine M; Vincelli, Amber J; Moise, Leonard; Martin, William; Knopf, Paul M

    2015-02-01

    Complement fragment C3d covalently attached to antigens enhances immune responses, particularly for antigens lacking T-cell epitopes. Enhancement has been attributed to receptor cross-linking between complement receptor CR2 (CD21) and polysaccharide antigen to surface IgM on naïve B cells. Paradoxically, C3d has still been shown to increase immune responses in CD21 knockout mice, suggesting that an auxiliary activation pathway exists. In prior studies, we demonstrated the CD21-independent C3d adjuvant effect might be due to T-cell recognition of C3d T-helper epitopes processed and presented by major histocompatibility complex class II on the B-cell surface. C3d peptide sequences containing concentrated clusters of putative human C3 T-cell epitopes were identified using the epitope-mapping algorithm, EpiMatrix. These peptide sequences were synthesized and shown in vitro to bind multiple human leukocyte antigen (HLA)-DR alleles with high affinity, and induce interferon-γ responses in healthy donor peripheral blood mononuclear cells. In the present studies, we establish further correlations between HLA binding and HLA-specific lymphocyte reactions with select epitope clusters. In addition, we show that the T-cell phenotype of C3d-specific reactive T cells is CD4(+)CD45RO(+) memory T cells. Finally, mutation of a single T-cell epitope residing within the P28 peptide segment of C3d resulted in significantly diminished adjuvant activity in BALB/c mice. Collectively, these studies support the hypothesis that the paradoxical enhancement of immune responses by C3d in the absence of CD21 is due to internalization and processing of C3d into peptides that activate autoreactive CD4(+) T-helper cells in the context of HLA class II. PMID:25385064

  9. Thermoelasticity of Fe7C3 under inner core conditions

    NASA Astrophysics Data System (ADS)

    Li, Y.; Vočadlo, L.; Brodholt, J.; Wood, I. G.

    2016-08-01

    It has recently been reported, on the basis of extrapolated experimental data, that the iron carbide, Fe7C3, has shear wave velocities and a Poisson's ratio consistent with the seismological values for the Earth's inner core and thus that Fe7C3 is a strong candidate for the inner core composition. In this study, using ab initio molecular dynamics simulations, we report the thermoelastic properties of Fe7C3 at 350 GPa up to its melting temperature. Due to significant elastic softening prior to melting, the calculated elastic properties, including wave velocities, do indeed agree well with those from seismology. However, the density was found to be much too low (by ~8%) when compared to geophysical data, and therefore, Fe7C3 must be ruled out as a major component of the Earth's inner core.

  10. Development of a C3 generic workstation: System overview

    NASA Technical Reports Server (NTRS)

    Strome, David R.

    1988-01-01

    A command, control, and communications (C3) environment is described which will be applied to the evaluation of performance of aircrews, particularly in situations in which they are subjected to chemical defense protection drugs and antihistamines.

  11. Photorespiration connects C3 and C4 photosynthesis.

    PubMed

    Bräutigam, Andrea; Gowik, Udo

    2016-05-01

    C4 plants evolved independently more than 60 times from C3 ancestors. C4 photosynthesis is a complex trait and its evolution from the ancestral C3 photosynthetic pathway involved the modification of the leaf anatomy and the leaf physiology accompanied by changes in the expression of thousands of genes. Under high temperature, high light, and the current CO2 concentration in the atmosphere, the C4 pathway is more efficient than C3 photosynthesis because it increases the CO2 concentration around the major CO2 fixating enzyme Rubisco. The oxygenase reaction and, accordingly, photorespiration are largely suppressed. In the present review we describe a scenario for C4 evolution that not only includes the avoidance of photorespiration as the major driving force for C4 evolution but also highlights the relevance of changes in the expression of photorespiratory genes in inducing and establishing important phases on the path from C3 to C4.

  12. An Observational Investigation of the Identity of B11244 (l-C3H+/C3H-)

    NASA Astrophysics Data System (ADS)

    McGuire, Brett A.; Carroll, P. Brandon; Gratier, Pierre; Guzmán, Viviana; Pety, Jerome; Roueff, Evelyne; Gerin, Maryvonne; Blake, Geoffrey A.; Remijan, Anthony J.

    2014-03-01

    Pety et al. have reported the detection of eight transitions of a closed-shell, linear molecule (B11244) in observations toward the Horsehead photodissociation region (PDR), which they attribute to the l-C3H+ cation. Recent high-level ab initio calculations have called this assignment into question; the anionic C3H- molecule has been suggested as a more likely candidate. Here, we examine observations of the Horsehead PDR, Sgr B2(N), TMC-1, and IRC+10216 in the context of both l-C3H+ and C3H-. We find no observational evidence of Ka = 1 lines, which should be present were the carrier indeed C3H-. Additionally, we find a strong anticorrelation between the presence of known molecular anions and B11244 in these regions. Finally, we discuss the formation and destruction chemistry of C3H- in the context of the physical conditions in the regions. Based on these results, we conclude there is little evidence to support the claim that the carrier is C3H-.

  13. Lifetimes of the ˜{A} States of the C_3-NE and C_3-AR Complexes

    NASA Astrophysics Data System (ADS)

    Wang, Yi-Jen; Chen, Chiao-Wei; Merer, Anthony J.; Hsu, Yen-Chu

    2013-06-01

    Under similar experimental conditions to our previous paper, the fluorescence lifetimes of the ˜{A} states of C_3-Ne and C_3-Ar have been determined. The uncertainties in the measured lifetimes are estimated to be better than 10%. About 50 perpendicular bands and 11 parallel bands of the ˜{A}-˜{X} system of C_3 were used to probe the fluorescence lifetimes of the Ne and Ar complexes. It is not possible to reduce the backing pressure while measuring lifetimes of the complexes; we therefore reduced the average pressure of the chamber to 1-2 × 10^{-5} torr by lowering the repetition rate. No sign of predissociation was found in either complex. Transitions to high vibrational levels of the ˜{A} state of C_3, above 4500 cm^{-1}, give weak laser-induced fluorescence signals, so that lifetime measurements are not possible for some of these bands. The lifetimes of the levels of the Ne complex lying below 4300 cm^{-1} are generally shorter than 300 ns, except for some levels with C-C stretch excitation. The lifetimes of the Ne complex behave quite similarly to those of C_3. In contrast, the lifetimes of the Ar complex do not follow the vibrational dependence of the lifetimes of C_3 and C_3-Ne. We speculate that the complicated lifetime pattern observed in the Ar complex can be attributed to interactions with nearby triplet levels.

  14. The APOA1/C3/A4/A5 cluster and markers of allostatic load in the Boston Puerto Rican Health Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The APOA1/C3/A4/A5 cluster encodes key regulators of plasma lipids. Interactions between dietary factors and single nucleotide polymorphisms (SNPs) in the cluster have been reported. Allostatic load, or physiological dysregulation in response to stress, has been implicated in shaping health disparit...

  15. The interstellar chemistry of H2C3O isomers

    NASA Astrophysics Data System (ADS)

    Loison, Jean-Christophe; Agúndez, Marcelino; Marcelino, Núria; Wakelam, Valentine; Hickson, Kevin M.; Cernicharo, José; Gerin, Maryvonne; Roueff, Evelyne; Guélin, Michel

    2016-03-01

    We present the detection of two H2C3O isomers, propynal and cyclopropenone, toward various starless cores and molecular clouds, together with upper limits for the third isomer propadienone. We review the processes controlling the abundances of H2C3O isomers in interstellar media showing that the reactions involved are gas-phase ones. We show that the abundances of these species are controlled by kinetic rather than thermodynamic effects.

  16. The interstellar chemistry of H2C3O isomers

    PubMed Central

    Loison, Jean-Christophe; Agúndez, Marcelino; Marcelino, Núria; Wakelam, Valentine; Hickson, Kevin M.; Cernicharo, José; Gerin, Maryvonne; Roueff, Evelyne; Guélin, Michel

    2016-01-01

    We present the detection of two H2C3O isomers, propynal and cyclopropenone, toward various starless cores and molecular clouds, together with upper limits for the third isomer propadienone. We review the processes controlling the abundances of H2C3O isomers in interstellar media showing that the reactions involved are gas-phase ones. We show that the abundances of these species are controlled by kinetic rather than thermodynamic effects. PMID:27013768

  17. Effect of sulfide ions on complement factor C3.

    PubMed Central

    Granlund-Edstedt, M; Johansson, E; Claesson, R; Carlsson, J

    1991-01-01

    In infected sites such as the gingival pockets of patients with periodontal disease, sulfide levels up to 1 mmol/liter may be reached. There is little information, however, on how sulfide may interact with the host defense. In a previous study (R. Claesson, M. Granlund-Edstedt, S. Persson, and J. Carlsson, Infect. Immun. 57:2776-2781, 1989), it was shown that polymorphonuclear leukocytes were able to kill bacteria in the presence of 1 mM sulfide. However, sulfide seemed to interfere with the opsonization of the bacteria. It has been claimed that sulfide may be toxic by splitting disulfide bonds of proteins. In the present study, serum was exposed to 2 mM sulfide under anaerobic conditions, and the capacity of sulfide to split disulfide bonds of 10 serum proteins involved in opsonization was evaluated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunodetection of the proteins after blotting. Sulfide had a low capacity to split the disulfide bonds of most proteins. Sulfide had, however, a pronounced effect on the complement component C3 in the form of C3bi. Sulfide released the C-terminal region of the alpha chain from C3bi. When C3 opsonizes bacteria, it is this region of C3bi which binds to complement receptor 3 (CR3) of the polymorphonuclear leukocytes. If sulfide has the same effect on C3bi deposited on the bacterial surface as it has on C3bi in solution, it will annihilate the very important contribution of C3bi to opsonization. Images PMID:1987085

  18. Complotype affects the extent of down-regulation by Factor I of the C3b feedback cycle in vitro.

    PubMed

    Lay, E; Nutland, S; Smith, J E; Hiles, I; Smith, R A G; Seilly, D J; Buchberger, A; Schwaeble, W; Lachmann, P J

    2015-08-01

    Sera from a large panel of normal subjects were typed for three common polymorphisms, one in C3 (R102G) and two in Factor H (V62I and Y402H), that influence predisposition to age-related macular degeneration and to some forms of kidney disease. Three groups of sera were tested; those that were homozygous for the three risk alleles; those that were heterozygous for all three; and those homozygous for the low-risk alleles. These groups vary in their response to the addition of exogenous Factor I when the alternative complement pathway is activated by zymosan. Both the reduction in the maximum amount of iC3b formed and the rate at which the iC3b is converted to C3dg are affected. For both reactions the at-risk complotype requires higher doses of Factor I to produce similar down-regulation. Because iC3b reacting with the complement receptor CR3 is a major mechanism by which complement activation gives rise to inflammation, the breakdown of iC3b to C3dg can be seen to have major significance for reducing complement-induced inflammation. These findings demonstrate for the first time that sera from subjects with different complement alleles behave as predicted in an in-vitro assay of the down-regulation of the alternative complement pathway by increasing the concentration of Factor I. These results support the hypothesis that exogenous Factor I may be a valuable therapeutic aid for down-regulating hyperactivity of the C3b feedback cycle, thereby providing a treatment for age-related macular degeneration and other inflammatory diseases of later life. PMID:25124117

  19. De novo C3 glomerulonephritis in a renal allograft.

    PubMed

    Nahm, Ji Hae; Song, Seung Hwan; Kim, Yu Seun; Cheong, Hae-Il; Lim, Beom Jin; Kim, Beom Seok; Jeong, Hyeon Joo

    2016-01-01

    C3 glomerulonephritis (C3GN) is a recently described, rare glomerular disease characterized by predominant or sole glomerular C3 deposits. Morphologic features of C3GN are similar to those of dense deposit disease (DDD); however, ribbon-like intramembranous electron-dense deposits are absent in the former. We report a case of de novo C3GN in a renal allograft with morphologic transformation to DDD. A 6-year-old boy presented with congenital left renal agenesis and right ureteropelvic junction obstruction. The patient underwent pyeloplasty but experienced recurrent urinary tract infections. At the age of 22 years, he received a renal allograft from a living related donor. C3GN was diagnosed after 1 year of transplantation; initial histology showed minimal mesangiopathy and this progressed to mesangial proliferation and membranoproliferative features over the next 7 years. Serum creatinine levels were stabilized with anti-rejection treatments for combating repeated episodes of acute rejection; however, glomerular and tubular band-like electron-dense deposits became evident.

  20. De novo C3 glomerulonephritis in a renal allograft.

    PubMed

    Nahm, Ji Hae; Song, Seung Hwan; Kim, Yu Seun; Cheong, Hae-Il; Lim, Beom Jin; Kim, Beom Seok; Jeong, Hyeon Joo

    2016-01-01

    C3 glomerulonephritis (C3GN) is a recently described, rare glomerular disease characterized by predominant or sole glomerular C3 deposits. Morphologic features of C3GN are similar to those of dense deposit disease (DDD); however, ribbon-like intramembranous electron-dense deposits are absent in the former. We report a case of de novo C3GN in a renal allograft with morphologic transformation to DDD. A 6-year-old boy presented with congenital left renal agenesis and right ureteropelvic junction obstruction. The patient underwent pyeloplasty but experienced recurrent urinary tract infections. At the age of 22 years, he received a renal allograft from a living related donor. C3GN was diagnosed after 1 year of transplantation; initial histology showed minimal mesangiopathy and this progressed to mesangial proliferation and membranoproliferative features over the next 7 years. Serum creatinine levels were stabilized with anti-rejection treatments for combating repeated episodes of acute rejection; however, glomerular and tubular band-like electron-dense deposits became evident. PMID:26986539

  1. Contribution of polymorphisms in the apolipoprotein AI-CIII-AIV cluster to hyperlipidaemia in patients with gout

    PubMed Central

    Cardona, F; Tinahones, F; Collantes, E; Escudero, A; Garcia-Fuentes, E; Soriguer, F

    2005-01-01

    Background: Studies have shown that hyperuricaemia is independently related to the insulin resistance syndrome and that polymorphisms of the apolipoprotein AI-CIII-AIV cluster are also related to insulin resistance. Objective: To study the prevalence of polymorphisms of the apolipoprotein AI-CIII-AIV cluster in persons with gout and to determine whether these polymorphisms contribute to the pathophysiology of gout or to altered lipid concentrations. Methods: Plasma cholesterol, triglycerides, uric acid, VLDL, LDL, IDL, and HDL triglycerides, cholesterol, and the renal excretion of uric acid were measured in 68 patients with gout with gout and 165 healthy subjects. Polymorphisms were studied by amplification and RFLP in all subjects, using XmnI and MspI in the apolipoprotein AI gene and SstI in the apolipoprotein CIII gene. Results: The A allele at position –75 bp in the apolipoprotein AI gene was more common in patients with gout than in controls (p = 0.01). Levels of cholesterol, triglycerides, uric acid, basal glycaemia, and HDL cholesterol were higher in the patients (p<0.001). In the patients there was also an interaction between mutations at the two polymorphic loci studied in the apolipoprotein AI gene (p = 0.04). An absence of the mutation at position –75 bp of the apolipoprotein AI gene resulted in increased plasma triglyceride levels. Conclusions: Gouty patients have an altered allelic distribution in the apolipoprotein AI-CIII-AIV cluster, which could lead to changes in levels of lipoproteins. This is not caused by a single mutation but rather by a combination of different mutations. PMID:15115711

  2. Highly Accurate Quantum-Chemical Calculations for the Interstellar Molecules C_3 and l-C_3H^+

    NASA Astrophysics Data System (ADS)

    Botschwina, Peter; Schröder, Benjamin; Stein, Christopher; Sebald, Peter; Oswald, Rainer

    2014-06-01

    Composite potential energy surfaces with coupled-cluster contributions up to CCSDTQP were constructed for C_3 and l-C_3H^+ and used in the calculation of spectroscopic properties. The use of very large AO basis sets and the consideration of higher-order correlation beyond CCSD(T) is of utmost importance for C_3 in order to arrive at quantitative spectroscopic data. The first detection of l-C_3H^+ in the interstellar medium was reported by Pety et al., who attributed 9 radio lines observed in the horsehead photodissociation region to that species. That assignment was questioned by the recent theoretical work of Huang et al. However, our more accurate calculations are well in support of the original assignment. The calculated ground-state rotational constant is B_0 = 11248 MHz, only 0.03% off from the radio astronomical value of 11244.9512±0.0015 MHz. The ratio of centrifugal distortion constants D_0(exp.)/D_e(theor.) of 1.8 is quite large, but reasonable in comparison with C_3O and C_3. J. Pety, P. Gratier, V. Guzmán, E. Roueff, M. Gerin et al., Astron. Astrophys. 2012, A68, 1-8. X. Huang, R. C. Fortenberry, T. J. Lee, Astrophys. J. Lett. 2013, 768:L25, 1-5. P. Botschwina, R. Oswald, J. Chem. Phys. 2008, 129, 044305

  3. A prevalent C3 mutation in aHUS patients causes a direct C3 convertase gain of function

    PubMed Central

    Roumenina, Lubka T.; Frimat, Marie; Miller, Elizabeth C.; Provot, Francois; Dragon-Durey, Marie-Agnes; Bordereau, Pauline; Bigot, Sylvain; Hue, Christophe; Satchell, Simon C.; Mathieson, Peter W.; Mousson, Christiane; Noel, Christian; Sautes-Fridman, Catherine; Halbwachs-Mecarelli, Lise; Atkinson, John P.; Lionet, Arnaud

    2012-01-01

    Atypical hemolytic uremic syndrome (aHUS) is a rare renal thrombotic microangiopathy commonly associated with rare genetic variants in complement system genes, unique to each patient/family. Here, we report 14 sporadic aHUS patients carrying the same mutation, R139W, in the complement C3 gene. The clinical presentation was with a rapid progression to end-stage renal disease (6 of 14) and an unusually high frequency of cardiac (8 of 14) and/or neurologic (5 of 14) events. Although resting glomerular endothelial cells (GEnCs) remained unaffected by R139W-C3 sera, the incubation of those sera with GEnC preactivated with pro-inflammatory stimuli led to increased C3 deposition, C5a release, and procoagulant tissue-factor expression. This functional consequence of R139W-C3 resulted from the formation of a hyperactive C3 convertase. Mutant C3 showed an increased affinity for factor B and a reduced binding to membrane cofactor protein (MCP; CD46), but a normal regulation by factor H (FH). In addition, the frequency of at-risk FH and MCP haplotypes was significantly higher in the R139W-aHUS patients, compared with normal donors or to healthy carriers. These genetic background differences could explain the R139W-aHUS incomplete penetrance. These results demonstrate that this C3 mutation, especially when associated with an at-risk FH and/or MCP haplotypes, becomes pathogenic following an inflammatory endothelium-damaging event. PMID:22246034

  4. 17 CFR 240.15c3-1d - Satisfactory Subordination Agreements (Appendix D to 17 CFR 240.15c3-1).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Agreements (Appendix D to 17 CFR 240.15c3-1). 240.15c3-1d Section 240.15c3-1d Commodity and Securities...-Counter Markets § 240.15c3-1d Satisfactory Subordination Agreements (Appendix D to 17 CFR 240.15c3-1). (a... (D). (2) Certain Definitions. For purposes of 17 CFR 240.15c3-1 and this Appendix (D): (i)...

  5. 17 CFR 240.15c3-1d - Satisfactory Subordination Agreements (Appendix D to 17 CFR 240.15c3-1).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Agreements (Appendix D to 17 CFR 240.15c3-1). 240.15c3-1d Section 240.15c3-1d Commodity and Securities...-Counter Markets § 240.15c3-1d Satisfactory Subordination Agreements (Appendix D to 17 CFR 240.15c3-1). (a... (D). (2) Certain Definitions. For purposes of 17 CFR 240.15c3-1 and this appendix (D): (i)...

  6. 17 CFR 240.15c3-1d - Satisfactory Subordination Agreements (Appendix D to 17 CFR 240.15c3-1).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Agreements (Appendix D to 17 CFR 240.15c3-1). 240.15c3-1d Section 240.15c3-1d Commodity and Securities...-Counter Markets § 240.15c3-1d Satisfactory Subordination Agreements (Appendix D to 17 CFR 240.15c3-1). (a... (D). (2) Certain Definitions. For purposes of 17 CFR 240.15c3-1 and this Appendix (D): (i)...

  7. 17 CFR 240.15c3-1d - Satisfactory Subordination Agreements (Appendix D to 17 CFR 240.15c3-1).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Agreements (Appendix D to 17 CFR 240.15c3-1). 240.15c3-1d Section 240.15c3-1d Commodity and Securities...-Counter Markets § 240.15c3-1d Satisfactory Subordination Agreements (Appendix D to 17 CFR 240.15c3-1). (a... (D). (2) Certain Definitions. For purposes of 17 CFR 240.15c3-1 and this Appendix (D): (i)...

  8. 17 CFR 240.15c3-1d - Satisfactory Subordination Agreements (Appendix D to 17 CFR 240.15c3-1).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Agreements (Appendix D to 17 CFR 240.15c3-1). 240.15c3-1d Section 240.15c3-1d Commodity and Securities...-Counter Markets § 240.15c3-1d Satisfactory Subordination Agreements (Appendix D to 17 CFR 240.15c3-1). (a... (D). (2) Certain Definitions. For purposes of 17 CFR 240.15c3-1 and this Appendix (D): (i)...

  9. 12 CFR 563c.3 - Qualification of public accountant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... REQUIREMENTS Form and Content of Financial Statements § 563c.3 Qualification of public accountant. (See also 17 CFR 210.2-01.) The term “qualified public accountant” means a certified public accountant or licensed... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Qualification of public accountant....

  10. 12 CFR 563c.3 - Qualification of public accountant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... REQUIREMENTS Form and Content of Financial Statements § 563c.3 Qualification of public accountant. (See also 17 CFR 210.2-01.) The term “qualified public accountant” means a certified public accountant or licensed... 12 Banks and Banking 5 2011-01-01 2011-01-01 false Qualification of public accountant....

  11. Implementing the C3 Framework: Monitoring the Instructional Shifts

    ERIC Educational Resources Information Center

    Herczog, Michelle M.

    2014-01-01

    The College, Career, and Civic Life (C3) Framework for Social Studies State Standards calls upon social studies teachers to enhance the rigor of civics, economics, geography, history and the other social studies disciplines while building the critical thinking, problem solving, and participatory skills of students to help them become actively…

  12. Hydrology of C-3 Watershed, Seney National Wildlife Refuge, Michigan

    USGS Publications Warehouse

    Sweat, Michael J.

    2001-01-01

    Proposed changes to watershed management practices near C-3 Pool at Seney National Wildlife Refuge will affect surface-water flow patterns, ground-water levels, and possibly local plant communities. Data were collected between fall 1998 and spring 2000 to document existing conditions and to assess potential changes in hydrology that might occur as a consequence of modifications to water management practices in C-3 watershed. Minimum and maximum measured inflows and outflows for the study period are presented in light of proposed management changes to C-3 watershed. Streamflows ranged from 0 to 8.61 cubic meters per second. Low or zero flow was generally measured in late summer and early fall, and highest flows were measured during spring runoff and winter rain events. Ground-water levels varied by about a half meter, with levels closest to or above the land surface during spring runoff into the early summer, and with levels generally below land surface during late fall into early winter. A series of optional management practices that could conserve and restore habitat of the C-3 watershed is described. Modifications to the existing system of a drainage ditch and control structures are examined, as are the possibilities of reconnecting streams to their historical channels and the construction of additional or larger control structures to further manage the distribution of water in the watershed. The options considered could reduce erosion, restore presettlement streamflow conditions, and modify the ground-water gradient.

  13. Effectiveness of mycophenolate mofetil in C3 glomerulonephritis.

    PubMed

    Rabasco, Cristina; Cavero, Teresa; Román, Elena; Rojas-Rivera, Jorge; Olea, Teresa; Espinosa, Mario; Cabello, Virginia; Fernández-Juarez, Gema; González, Fayna; Ávila, Ana; Baltar, José María; Díaz, Montserrat; Alegre, Raquel; Elías, Sandra; Antón, Monserrat; Frutos, Miguel Angel; Pobes, Alfonso; Blasco, Miguel; Martín, Francisco; Bernis, Carmen; Macías, Manuel; Barroso, Sergio; de Lorenzo, Alberto; Ariceta, Gema; López-Mendoza, Manuel; Rivas, Begoña; López-Revuelta, Katia; Campistol, José María; Mendizábal, Santiago; de Córdoba, Santiago Rodríguez; Praga, Manuel

    2015-11-01

    C3 glomerulonephritis is a clinicopathologic entity defined by the presence of isolated or dominant deposits of C3 on immunofluorescence. To explore the effect of immunosuppression on C3 glomerulonephritis, we studied a series of 60 patients in whom a complete registry of treatments was available over a median follow-up of 47 months. Twenty patients had not received immunosuppressive treatments. In the remaining 40 patients, 22 had been treated with corticosteroids plus mycophenolate mofetil while 18 were treated with other immunosuppressive regimens (corticosteroids alone or corticosteroids plus cyclophosphamide). The number of patients developing end-stage renal disease was significantly lower among treated compared with untreated patients (3 vs. 7 patients, respectively). No patient in the corticosteroids plus mycophenolate mofetil group doubled serum creatinine nor developed end-stage renal disease, as compared with 7 (significant) and 3 (not significant), respectively, in patients treated with other immunosuppressive regimens. Renal survival (100, 80, and 72% at 5 years) and the number of patients achieving clinical remission (86, 50, and 25%) were significantly higher in patients treated with corticosteroids plus mycophenolate mofetil as compared with patients treated with other immunosuppressive regimens and untreated patients, respectively. Thus, immunosuppressive treatments, particularly corticosteroids plus mycophenolate mofetil, can be beneficial in C3 glomerulonephritis. PMID:26221755

  14. Effectiveness of mycophenolate mofetil in C3 glomerulonephritis.

    PubMed

    Rabasco, Cristina; Cavero, Teresa; Román, Elena; Rojas-Rivera, Jorge; Olea, Teresa; Espinosa, Mario; Cabello, Virginia; Fernández-Juarez, Gema; González, Fayna; Ávila, Ana; Baltar, José María; Díaz, Montserrat; Alegre, Raquel; Elías, Sandra; Antón, Monserrat; Frutos, Miguel Angel; Pobes, Alfonso; Blasco, Miguel; Martín, Francisco; Bernis, Carmen; Macías, Manuel; Barroso, Sergio; de Lorenzo, Alberto; Ariceta, Gema; López-Mendoza, Manuel; Rivas, Begoña; López-Revuelta, Katia; Campistol, José María; Mendizábal, Santiago; de Córdoba, Santiago Rodríguez; Praga, Manuel

    2015-11-01

    C3 glomerulonephritis is a clinicopathologic entity defined by the presence of isolated or dominant deposits of C3 on immunofluorescence. To explore the effect of immunosuppression on C3 glomerulonephritis, we studied a series of 60 patients in whom a complete registry of treatments was available over a median follow-up of 47 months. Twenty patients had not received immunosuppressive treatments. In the remaining 40 patients, 22 had been treated with corticosteroids plus mycophenolate mofetil while 18 were treated with other immunosuppressive regimens (corticosteroids alone or corticosteroids plus cyclophosphamide). The number of patients developing end-stage renal disease was significantly lower among treated compared with untreated patients (3 vs. 7 patients, respectively). No patient in the corticosteroids plus mycophenolate mofetil group doubled serum creatinine nor developed end-stage renal disease, as compared with 7 (significant) and 3 (not significant), respectively, in patients treated with other immunosuppressive regimens. Renal survival (100, 80, and 72% at 5 years) and the number of patients achieving clinical remission (86, 50, and 25%) were significantly higher in patients treated with corticosteroids plus mycophenolate mofetil as compared with patients treated with other immunosuppressive regimens and untreated patients, respectively. Thus, immunosuppressive treatments, particularly corticosteroids plus mycophenolate mofetil, can be beneficial in C3 glomerulonephritis.

  15. Identification, mapping and linkage analysis of randomly amplified DNA polymorphisms in Tetrahymena thermophila

    SciTech Connect

    Brickner, J.H.; Lynch, T.J.; Zeilinger, D.; Orias, E.

    1996-06-01

    Using the random amplified polymorphic DNA (RAPD) technique and exploiting the unique genetics of Tetrahymena thermophila, we have identified and characterized 40 DNA polymorphisms occurring between two inbred strains (B and C3) of this ciliated protozoan. These RAPD markers permit the PCR amplification of a DNA species using template DNA from SB1969 (B strain) but fail to do so using DNA from C3-368-5 (C3 strain). Polymorphisms were mapped to chromosomes using a panel of monosomic strains constructed by crossing B strain-derived nullisomic strains to inbred strain C3. They map to all five chromosomes and appear to be evenly distributed throughout the genome. Chromosomal groups were then analyzed for linkage using meiotic segregants; four linkage groups were identified in chromosomes 1R, 2L, 3 and 5. The RAPD method appears useful for the construction of a genetic map of the Tetrahymena genome based on DNA polymorphisms. 37 refs., 4 figs., 6 tabs.

  16. Carbon nitride frameworks and dense crystalline polymorphs

    NASA Astrophysics Data System (ADS)

    Pickard, Chris J.; Salamat, Ashkan; Bojdys, Michael J.; Needs, Richard J.; McMillan, Paul F.

    2016-09-01

    We used ab initio random structure searching (AIRSS) to investigate polymorphism in C3N4 carbon nitride as a function of pressure. Our calculations reveal new framework structures, including a particularly stable chiral polymorph of space group P 43212 containing mixed s p2 and s p3 bonding, that we have produced experimentally and recovered to ambient conditions. As pressure is increased a sequence of structures with fully s p3 -bonded C atoms and three-fold-coordinated N atoms is predicted, culminating in a dense P n m a phase above 250 GPa. Beyond 650 GPa we find that C3N4 becomes unstable to decomposition into diamond and pyrite-structured CN2.

  17. Insights into the Effects of Complement Factor H on the Assembly and Decay of the Alternative Pathway C3 Proconvertase and C3 Convertase.

    PubMed

    Bettoni, Serena; Bresin, Elena; Remuzzi, Giuseppe; Noris, Marina; Donadelli, Roberta

    2016-04-01

    The activated fragment of C3 (C3b) and factor B form the C3 proconvertase (C3bB), which is cleaved by factor D to C3 convertase (C3bBb). Older studies (Conrad, D. H., Carlo, J. R., and Ruddy, S. (1978)J. Exp. Med.147, 1792-1805; Pangburn, M. K., and Müller-Eberhard, H. J. (1978)Proc. Natl. Acad. Sci. U.S.A.75, 2416-2420; Kazatchkine, M. D., Fearon, D. T., and Austen, K. F. (1979)J. Immunol.122, 75-81) indicated that the complement alternative pathway regulator factor H (FH) competes with factor B for C3b binding; however, the capability of FH to prevent C3bB assembly has not been formally investigated. Moreover, in the few published studies FH did not favor C3bB dissociation. Whether FH may affect C3bBb formation from C3bB is unknown. We set up user-friendly assays based on combined microplate/Western blotting techniques that specifically detect either C3bB or C3bBb, with the aim of investigating the effect of FH on C3bB assembly and decay and C3bBb formation and decay. We document that FH does not affect C3bB assembly, indicating that FH does not efficiently compete with factor B for C3b binding. We also found that FH does not dissociate C3bB. FH showed a strong C3bBb decay-accelerating activity, as reported previously, and also exerted an apparent inhibitory effect on C3bBb formation. The latter effect was not fully attributable to a rapid FH-mediated dissociation of C3bBb complexes, because blocking decay with properdin and C3 nephritic factor did not restore C3bBb formation. FH almost completely prevented release of the smaller cleavage subunit of FB (Ba), without modifying the amount of C3bB complexes, suggesting that FH inhibits the conversion of C3bB to C3bBb. Thus, the inhibitory effect of FH on C3bBb formation is likely the sum of inhibition of C3bB conversion to C3bBb and of C3bBb decay acceleration. Further studies are required to confirm these findings in physiological cell-based settings.

  18. Pressure Effects on Product Channels of the Allyl Radical Reactions; C3H5+C3H5 and C3H5+CH3

    NASA Astrophysics Data System (ADS)

    Halpern, J. B.; N'Doumi, M.; Fahr, A.

    2011-12-01

    Relatively large hydrocarbon molecules (C4, C6 and larger) have been detected in several planetary environments. The mechanism for the formation of such large molecular species and detailed mechanism for their potential destruction are not well understood and are of considerable current interest. Previously we have studied the kinetics and product channels of small unsaturated hydrocarbon radical (C2 and C3s) reactions relevant to planetary atmospheric modeling. Reactions of C2 radicals (such as vinyl, H2CCH and ethynyl C2H) and C3 radicals (such as propargyl, HCCCH2) can affect the abundances of a large number of stable observable C3, C4, C5, C6 and larger molecules, including linear, aromatic and even poly aromatic molecules. Pressure-dependent product yields have been determined experimentally for the self- and cross-radical reactions performed at 298 K and at pressures between ~4 Torr (0.5 kPa) and 760 Torr (101 kPa). Final reaction products were quantitatively determined using a gas chromatograph with mass spectrometry/flame ionization detection (GC/MS/FID). In some cases complementary computational studies extended the pressure and temperature range of the experiments and provided valuable information on the complex reaction mechanisms. Theses studies provide a systematic framework so that important energetic and structural parameters for radical-radical reactions can be assessed. Here we report recent results for the allyl radical reactions H2CCCH3+ H2CCCH3 and H2CCCH3+CH3. For the allyl radical self-reaction, at high pressures the "head -to-head", combination channel forming 1,5-hexadiene is dominant with a combination/disproportionation = 1,5-hexadiene/propyne ratio of about 24 at 500 Torr (67 kPa, T=298K). At low pressures the ratio is substantially reduced to about 1.2 (at 0.3 kPa) and other major products are observed including allene, propene, 1-butene and propyne.

  19. Assimilatory Sulfate Reduction in C3, C3-C4, and C4 Species of Flaveria1

    PubMed Central

    Koprivova, Anna; Melzer, Michael; von Ballmoos, Peter; Mandel, Therese; Brunold, Christian; Kopriva, Stanislav

    2001-01-01

    The activity of the enzymes catalyzing the first two steps of sulfate assimilation, ATP sulfurylase and adenosine 5′-phosphosulfate reductase (APR), are confined to bundle sheath cells in several C4 monocot species. With the aim to analyze the molecular basis of this distribution and to determine whether it was a prerequisite or a consequence of the C4 photosynthetic mechanism, we compared the intercellular distribution of the activity and the mRNA of APR in C3, C3-C4, C4-like, and C4 species of the dicot genus Flaveria. Measurements of APR activity, mRNA level, and protein accumulation in six Flaveria species revealed that APR activity, cysteine, and glutathione levels were significantly higher in C4-like and C4 species than in C3 and C3-C4 species. ATP sulfurylase and APR mRNA were present at comparable levels in both mesophyll and bundle sheath cells of C4 species Flaveria trinervia. Immunogold electron microscopy demonstrated the presence of APR protein in chloroplasts of both cell types. These findings, taken together with results from the literature, show that the localization of assimilatory sulfate reduction in the bundle sheath cells is not ubiquitous among C4 plants and therefore is neither a prerequisite nor a consequence of C4 photosynthesis. PMID:11598228

  20. Arabidopsis C3H14 and C3H15 have overlapping roles in the regulation of secondary wall thickening and anther development.

    PubMed

    Chai, Guohua; Kong, Yingzhen; Zhu, Ming; Yu, Li; Qi, Guang; Tang, Xianfeng; Wang, Zengguang; Cao, Yingping; Yu, Changjiang; Zhou, Gongke

    2015-05-01

    Plant tandem CCCH zinc finger (TZF) proteins play diverse roles in developmental and adaptive processes. Arabidopsis C3H14 has been shown to act as a potential regulator of secondary wall biosynthesis. However, there is lack of direct evidence to support its functions in Arabidopsis. It is demonstrated here that C3H14 and its homologue C3H15 redundantly regulate secondary wall formation and that they additionally function in anther development. Plants with double, but not single, T-DNA mutants for C3H14 or C3H15 have few pollen grains and thinner stem secondary walls than the wild type. Plants homozygous for c3h14 and heterozygous for c3h15 [c3h14 c3h15(±)] have slightly thinner secondary walls than plants heterozygous for c3h14 and homozygous for c3h15 [c3h14(±) c3h15], and c3h14(±) c3h15 have lower fertility. Overexpression of C3H14 or C3H15 led to increased secondary wall thickness in stems and the ectopic deposition of secondary walls in various tissues, but did not affect anther morphology. Transcript profiles from the C3H14/15 overexpression and c3h14 c3h15 plants revealed marked changes in the expression of many genes associated with cell wall metabolism and pollen formation. Subcellular localization and biochemical analyses suggest that C3H14/15 might function at both the transcriptional and post-transcriptional levels.

  1. Preface: Graphene and C3N4-based photocatalysts

    NASA Astrophysics Data System (ADS)

    Yu, Jiaguo; Jaroniec, Mietek

    2015-12-01

    In recent years, 2D layered materials including graphene and g-C3N4 have attracted more and more attention in the field of photocatalysis and have become the research hotspots due to their broad applications in energy and environment-related areas. A critical appraisal of recent developments related to these important materials was the main theme of the 1st International Workshop on Graphene and C3N4-based Photocatalysts (IWGCP) held at the Wuhan University of Technology, Wuhan, China on June 5-8, 2015. This workshop was jointly organized by Wuhan University of Technology, Jianghan University and Changsha University, China. More than 140 scientists from four continents (Asia, America, Australia and Europe) participated in this workshop, the agenda of which included 8 plenary lectures, 17 keynote lectures, 11 invited lectures, 6 oral presentations and 61 posters.

  2. Deuterium hyperfine structure in interstellar C3HD.

    PubMed

    Bell, M B; Watson, J K; Feldman, P A; Matthews, H E; Madden, S C; Irvine, W M

    1987-05-22

    The deuterium nuclear quadrupole hyperfine structure of the transition 1(10)-1(01) of the ring molecule cyclopropenylidene-d1 (C3HD) has been observed in emission from interstellar molecular clouds. The narrowest linewidths (approximately 7 kHz) so far observed are in the cloud L1498. The derived D coupling constants Xzz = 186.9(1.4) kHz, eta=0.063(18) agree well with correlations based on other molecules.

  3. High-Resolution Infrared Spectroscopy of Ge_2C_3

    NASA Astrophysics Data System (ADS)

    Thorwirth, S.; Lutter, V.; Schlemmer, S.; Giesen, T. F.; Gauss, J.

    2013-06-01

    Carbon-rich systems are of great importance in diverse areas of research like material science as well as astro- and structural chemistry. Despite this relevance, our knowledge of smaller cluster units is still fragmentary, particularly with respect to investigations at high-spectral resolution in the gas phase. Unequivocal assignment of spectral features to their molecular carriers is critically dependent on predictions from high-level quantum-chemical calculations. In turn, high-resolution studies provide useful information to assess the predictive power of quantum-chemical methods. This is particularly interesting for cluster systems harboring heavy elements for which so far relatively little is known from experiment. With this contribution, we would like to present a recent gas-phase study of a polyatomic germanium-carbon cluster, linear Ge_2C_3 (Ge=C=C=C=Ge), which was previously studied in an Ar matrix. The cluster was produced through laser ablation of germanium-graphite sample rods and observed in a free jet at wavelengths around 5μm. Additionally, quantum-chemical calculations of Ge_2C_3 were performed at the CCSD(T) level of theory. The production and observation of Ge_2C_3 suggests that many more binary clusters should be amenable to high-resolution spectroscopic techniques not only in the infrared but also in the microwave region. D. L. Robbins, C. M. L. Rittby, and W. R. M. Graham, J. Chem. Phys. 114, 3570 (2001).

  4. Astronomical identification of the C3H radical

    NASA Technical Reports Server (NTRS)

    Thaddeus, P.; Gottlieb, C. A.; Hjalmarson, A.; Johansson, L. E. B.; Irvine, W. M.

    1985-01-01

    The C3H radical has been identified in the millimeter-wave spectra of IRC +10216 and TMC-1. In IRC +10216, four rotational transitions have been observed, three in the lower fine-structure ladder (2Pi1/2) and one in the upper (2Pi3/2), each a resolved or partially resolved lambda-doublet. In TMC-1, both lambda components of the lowest lying 3/2-1/2 transition of the 2Pi1/2 ladder have been observed, each with well-resolved hfs. In IRC +10216, the excitation of C3H is similar to that of SiCC: the rotational temperature Trot within the 2Pi1/2 ladder is low (8.5 K), because of rapid radiative decay, while Trot across the ladders is high (about 52 K), because interconnecting far-IR radiative transitions are only weakly permitted. The column density of C3H in IRC +10216 averaged over the estimated source diameter of 84 arcsec is 2.8 x 10 to the 13th/sq cm, an order of magnitude less than that of C2H and C4H.

  5. The Climate Change Consortium of Wales (C3W)

    NASA Astrophysics Data System (ADS)

    Hendry, K. R.; Reis, J.; Hall, I. R.

    2011-12-01

    In response to the complexity and multidisciplinary nature of climate change research, the Climate Change Consortium of Wales (C3W) was formed in 2009 by the Welsh universities of Aberystwyth, Bangor, Cardiff and Swansea. Initially funded by Welsh Government, through the Higher Education Funding Council for Wales, the Countryside Council for Wales and the universities, C3W aims to bring together climate change researchers from a wide range of disciplines to explore scientific and sociological drivers, impacts and implications at local, national and international scale. The specific aims are to i) improve our fundamental understanding of the causes, nature, timing and consequences of climate change on Planet Earth's environment and on humanity, and ii) to reconfigure climate research in Wales as a recognisable centre of excellence on the world stage. In addition to improving the infrastructure for climate change research, we aim to improve communication, networking, collaborative research, and multidisciplinary data assimilation within and between the Welsh universities, and other UK and international institutions. Furthermore, C3W aims to apply its research by actively contributing towards national policy development, business development and formal and informal education activities within and beyond Wales.

  6. Timing of eculizumab therapy for C3 glomerulonephritis

    PubMed Central

    Rodriguez-Osorio, Laura; Ortiz, Alberto

    2015-01-01

    Eculizumab is an anti-C5 antibody that inhibits C5 cleavage and prevents the generation of the terminal complement complex C5b-9. Eculizumab is licensed to treat paroxysmal nocturnal haemoglobinuria or atypical haemolytic uraemic syndrome (aHUS). Clinical trials are ongoing for C3 glomerulopathy. Given the unfamiliarity of physicians with these rare diseases and the variability of clinical presentation, a delayed initiation of eculizumab therapy is common. Thus, the question arises as to what extent improvement of kidney function may be expected when patients have been dialysis dependent for weeks or months already when eculizumab is initiated. Furthermore, given the high cost and potential adverse effects of eculizumab, the question arises of when to stop therapy because of futility when patients with kidney-only manifestations remain dialysis dependent. In literature reports, eculizumab was stopped as early as after 3 weeks because the patient remained dialysis dependent. In this issue of CKJ, Inman et al. report on eculizumab-induced reversal of dialysis-dependent kidney failure from C3 glomerulonephritis, illustrating both the potential benefit of eculizumab for this complement-mediated disease and the need for lengthy therapy—dialysis independency was reached after 5 months of eculizumab. Indeed, there are reports of renal function recovery when eculizumab was initiated after 4 months on dialysis and of recovery of renal function 2.0–3.5 months after initiation of eculizumab in dialysis-dependent patients with C3 glomerulopathy or aHUS. PMID:26251715

  7. C3: A comprehensive physician activity and billing tool

    PubMed

    Hirschl; Sikina; Keller; Kastle; McConnell; Greenfield; Plachta

    2000-01-01

    Purpose: The Clinical Charge Capture system (C3) was developed at the University of Michigan to increase the efficiency and accuracy with which information about physician activity and billing is tracked in academic medical centers. Description: This Oracle-based, Visual Basic system integrates the operating room scheduling system, transcription database, clinical data repository, referring physician database, and IDX to allow physicians and staff to perform paperless and on-line standard tasks such as preauthorizing procedures; creating a bill which describes the charges for procedures performed along with their supporting diagnoses; identifying inpatient daily care and consult charges; dictating, editing, signing, and providing attestations for procedural and inpatient notes (menu-driven boilerplate notes are used for common procedures); submitting of charges on-line to IDX; and downloading of payment data from IDX. A messaging system between physicians and billing specialists allows questions to be posed regarding coding issues and options. Summary information about charges is presented and the status of the bill as it progresses through the internal review and billing process is demonstrated. Any missing data are flagged such that delivery of a bill is accurate, timely, and complete. Outpatient clinic visit charges are acquired on line using bar code technology with direct download of clinic charges to IDX. Generation of charges and referral letters may be performed immediately following the performance of a procedure or patient encounter or subsequently in the office. Resident activity is also tracked. Finally, search functions are provided which allow the program to serve as a clinical information research database. Results: The time to bill submission for operative procedures in fiscal year 1996 (Pre-C3) when compared to 1999 (Post-C3) decreased in each individual surgical division (See figure)as well as for the overall Department (Total: mean Pre-C3=40 days

  8. Formation of C3 and C2 in Cometary Comae

    NASA Astrophysics Data System (ADS)

    Hölscher, Alexander

    2015-03-01

    Comets are remnants from the Solar System formation. They reside at large distances from the Sun and are believed to store deep freeze imprints of the chemical and physical conditions at the time the Solar System formed. The main ice component of a comet is H2O followed by CO and CO2 with additional small amounts of molecules with varying complexity. Comets also contain large amounts of dust. If a comet approaches the Sun the ices begin to sublimate giving rise to the cometary coma. The molecules producing the coma can be observed in the infrared, the radio wavelength range and at optical wavelengths. To constrain the formation of the Solar System, models require knowledge of the composition for a statistically significant number of comets. This favors optical observations of e.g. C3 (tricarbon) and C2 (dicarbon) since these species allow observations even of relatively faint comets and do not require space missions (infrared observations). However, one has to link these observed photodissociation product species (daughter species) to the molecules that originally sublimated from the comet nucleus surface, i.e. the so-called parent molecules, as e.g. C2H2 (acetylene) for C2. However, for C3 no parent molecules have been identified so far. This thesis investigates the formation of C3 and C2 radicals in cometary comae due to photodissociation of observed and in the literature proposed hydrocarbon parent molecules. For this purpose a one-dimensional multi-fluid coma chemistry model has been improved and applied. This work added new photo reactions to the model, updated the hydrocarbon photo rate coefficients and quantified their uncertainty. A sensitivity analysis has been carried out to determine the reactions whose uncertainty most affect the model output uncertainty. Special attention should be paid to these so-called key reactions in future laboratory experiments and quantum chemical computations to reduce the model output uncertainty more effectively. This will

  9. Laboratory microwave spectrum of the cyclic C3D radical

    SciTech Connect

    Yamamoto, Satoshi; Saito, Shuji )

    1990-11-01

    The rotational spectral lines of the cyclic C3D radical in the 2B2 electronic ground state are detected in the laboratory. The radical is produced by discharging a gaseous mixture of C2D2, Co, and He, and the spectrum is observed in the 148-360 GHz region. The molecular constants including hyperfine coupling constants due to the D nucleus are determined by the least-squares analysis from 52 observed line frequencies. The frequencies of several low-N transitions needed for future radioastronomical observations are calculated from the molecular constants. 21 refs.

  10. The C3E Women in Clean Energy Symposium

    SciTech Connect

    Saylors-Laster, Kim; Kirsch, Emily; Brown, Sandra; Jordan, Rhonda; Mukherjee, Anuradha; Martin, Cheryl; Madden, Alice; Araujo, Kathy

    2013-09-30

    The Clean Energy Education & Empowerment initiative (C3E), provides a forum for thought leaders across the clean energy sector to devise innovative solutions to the nation's most pressing energy challenges. This year, the symposium was held at MIT's Media Lab in Cambridge, MA, on September 19-20, 2013. What sets the annual conference apart is its focus on building a strong community of professionals dedicated to advancing more women leaders in clean energy fields. By working to leverage the skills, talents and perspectives of women, the symposium helps to better position the U.S. to lead the global clean energy revolution.

  11. MCCx C3I Control Center Interface Emulator

    NASA Technical Reports Server (NTRS)

    Mireles, James R.

    2010-01-01

    This slide presentation reviews the project to develop and demonstrate alternate Information Technologies and systems for new Mission Control Centers that will reduce the cost of facility development, maintenance and operational costs and will enable more efficient cost and effective operations concepts for ground support operations. The development of a emulator for the Control Center capability will enable the facilities to conduct the simulation requiring interactivity with the Control Center when it is off line or unavailable, and it will support testing of C3I interfaces for both command and telemetry data exchange messages (DEMs).

  12. The C3E Women in Clean Energy Symposium

    ScienceCinema

    Saylors-Laster, Kim; Kirsch, Emily; Brown, Sandra; Jordan, Rhonda; Mukherjee, Anuradha; Martin, Cheryl; Madden, Alice; Araujo, Kathy

    2016-07-12

    The Clean Energy Education & Empowerment initiative (C3E), provides a forum for thought leaders across the clean energy sector to devise innovative solutions to the nation's most pressing energy challenges. This year, the symposium was held at MIT's Media Lab in Cambridge, MA, on September 19-20, 2013. What sets the annual conference apart is its focus on building a strong community of professionals dedicated to advancing more women leaders in clean energy fields. By working to leverage the skills, talents and perspectives of women, the symposium helps to better position the U.S. to lead the global clean energy revolution.

  13. Beryllium-induced immune response in C3H mice

    SciTech Connect

    Benson, J.M.; Bice, D.E.; Nikula, K.J.

    1995-12-01

    Studies conducted at ITRI over the past several years have investigated whether Beagle dogs, monkeys, and mice are suitable models for human chronic beryllium-induced lung disease (CBD). Recent studies have focused on the histopathological and immunopathological changes occurring in A/J and C3H/HeJ mice acutely exposed by inhalation to Be metal. Lung lesions in both strains of mice included focal lymphocyte aggregates comprised primarily of B lymphocytes and lesser amounts of T-helper lymphocytes and microgranulomas consisting chiefly of macrophages and T-helper lymphocytes. The distribution of proliferating cells within the microgranulomas was similar to the distribution of T-helper cells. These results strongly suggested that A/J and C3H/HeJ mice responded to inhaled Be metal in a fashion similar to humans in terms of pulmonary lesions and the apparent in situ proliferation of T-helper cells. Results of these studies confirm lymphocyte involvement in the pulmonary response to inhaled Be metal.

  14. A search for interstellar oxiranecarbonitrile (C3H3NO).

    PubMed

    Dickens, J E; Irvine, W M; Ohishi, M; Arrhenius, G; Pitsch, S; Bauder, A; Muller, F; Eschenmoser, A

    1996-04-01

    We report a search in cold, quiescent and in 'hot core' type interstellar molecular clouds for the small cyclic molecule oxiranecarbonitrile (C3H3NO), which has been suggested as a precursor of important prebiotic molecules. We have determined upper limits to the column density and fractional abundance for the observed sources and find that, typically, the fractional abundance by number relative to molecular hydrogen of C3H3NO is less than a few times 10(-10). This limit is one to two orders of magnitude less than the measured abundance of such similarly complex species as CH3CH2CN and HCOOCH3 in well-studied hot cores. A number of astrochemical discoveries were made, including the first detection of the species CH3CH2CN in the massive star-forming clouds G34.3+0.2 and W51M and the first astronomical detections of some eight rotational transitions of CH3CH2CN, CH3CCH, and HCOOCH3. In addition, we found 8 emission lines in the 89 GHz region and 18 in the 102 GHz region which we were unable to assign.

  15. A Search for Interstellar Oxiranecarbonitrile (C3H3NO)

    NASA Technical Reports Server (NTRS)

    Dicken, J. E.; Irvine, W. M.; Ohishi, M.; Arrhenius, G.; Bauder, A.; Mueller, F.; Eschenmoser, A.

    1996-01-01

    We report a search in cold, quiescent and in 'hot core' type interstellar molecular clouds for the small cyclic molecule oxiranecarbonitrile (C3H3NO), which has been suggested as a precursor of important prebiotic molecules. We have determined upper limits to the column density and fractional abundance for the observed sources and find that, typically, the fractional abundance by number relative to molecular hydrogen Of C3H3NO is less than a few times 10(exp -10). This limit is one to two orders of magnitude less than the measured abundance of such similarly complex species as CH3CH2CN and HCOOCH3 in well-studied hot cores. A number of astrochemical discoveries were made, including the first detection of the species CH3CH2CN in the massive star-forming clouds G34.3+0.2 and W51M and the first astronomical detections of some eight rotational transitions of CH3CH2CN, CH3CCH, and HCOOCH3. In addition, we found 8 emission lines in the 89 GHz region and 18 in the 102 GHz region which we were unable to assign.

  16. Complement fragments C3b and iC3b coupled to latex induce a respiratory burst in human neutrophils.

    PubMed

    Hoogerwerf, M; Weening, R S; Hack, C E; Roos, D

    1990-02-01

    The complement fragments C3b and iC3b were purified from human serum by affinity chromatography with Sepharose-coupled monoclonal antibody against the C3d region of C3. The resulting preparations were more than 95% pure and contained less than 0.1% native IgG. Purified C3b and iC3b were coupled to latex beads (0.8 micron diameter) by means of F(ab')2 fragments of monoclonal antibodies against the beta chain or the C3d region of C3, thus orienting the C3b and the iC3b on the latex with the C3b- and iC3b-specific regions outwards. These particles were found to activate the respiratory burst of freshly isolated human neutrophils to 20-30% of the maximal capacity. Latex particles randomly coated with C3b or iC3b were about 3 times less stimulatory. C3b, iC3b and IgG coupled to latex in an oriented fashion were about equally effective in stimulating the respiratory burst. Neutrophils from a patient with a total deficiency of CR3 responded normally to C3b-coated latex but did not respond to iC3b-coated latex. A monoclonal antibody against the alpha chain of CR3 inhibited the activation by iC3b-coated latex and a polyclonal antibody against CR1 partially inhibited the activation by C3b-coated latex. We found an additive effect between IgG-coated latex and C3b-coated latex, regardless of the presence of IgG and C3b on the same particle or on different particles. Thus, binding of ligands to either CR1 or CR3 per se is sufficient to induce an activating signal to the NADPH oxidase in human neutrophils.

  17. Infrared Predissociation Spectroscopy of the Hydrocarbon Cations C_3H^+, C_2H^+, and C_3H_2^+

    NASA Astrophysics Data System (ADS)

    Brünken, Sandra; Lipparini, Filippo; Gauss, Jürgen; Stoffels, Alexander; Redlich, Britta; van der Meer, Lex; Berden, Giel; Oomens, Jos; Schlemmer, Stephan

    2016-06-01

    Reactive hydrocarbon cations play an important role in the astrochemistry of the interstellar medium, but spectroscopic data, needed for their identification in astronomical observations, is sparse. Here we report the first gas-phase vibrational spectra of the linear C_3H^+ (^1 Σ), the radical cation C_2H^+ (^3 Π), and the linear-/cyclic-C_3H_2^+ (^2 Π /^2A_1, resp.). Broadband spectra were recorded by Ne- and He-messenger infrared-predissociation (IR-PD) action spectroscopy in a cryogenic (4-11 K) ion trap instrument (FELion) in the 250-3500 {wn} range using a free electron laser and a MIR-OPO at the FELIX (Free-Electron Laser for Infrared eXperiments) laboratory. The band positions (determined with a precision of 1-2 wn) covering the C-H and C-C stretching as well as several bending modes are compared to high-level (CCSD(T) with large basis sets) quantum-chemical calculations with an emphasis on anharmonic effects and on the influence of the rare-gas messenger atom. The experimental and theoretical data provide a solid basis for subsequent IR high-resolution studies, with the ultimate goal to predict and measure accurate rotational spectra for a radio-astronomical search of these molecular ions in space.

  18. C3 generic workstation: Performance metrics and applications

    NASA Technical Reports Server (NTRS)

    Eddy, Douglas R.

    1988-01-01

    The large number of integrated dependent measures available on a command, control, and communications (C3) generic workstation under development are described. In this system, embedded communications tasks will manipulate workload to assess the effects of performance-enhancing drugs (sleep aids and decongestants), work/rest cycles, biocybernetics, and decision support systems on performance. Task performance accuracy and latency will be event coded for correlation with other measures of voice stress and physiological functioning. Sessions will be videotaped to score non-verbal communications. Physiological recordings include spectral analysis of EEG, ECG, vagal tone, and EOG. Subjective measurements include SWAT, fatigue, POMS and specialized self-report scales. The system will be used primarily to evaluate the effects on performance of drugs, work/rest cycles, and biocybernetic concepts. Performance assessment algorithms will also be developed, including those used with small teams. This system provides a tool for integrating and synchronizing behavioral and psychophysiological measures in a complex decision-making environment.

  19. Synthesis of C3/C1-Substituted Tetrahydroisoquinolines.

    PubMed

    Mihoubi, Mohamed; Micale, Nicola; Scala, Angela; Jarraya, Raoudha Mezghani; Bouaziz, Amira; Schirmeister, Tanja; Risitano, Francesco; Piperno, Anna; Grassi, Giovanni

    2015-01-01

    A broad biological screening of the natural alkaloid N-methylisosalsoline (2) extracted from Hammada scoparia leaves against a panel of human and parasitic proteases revealed an interesting activity profile of 2 towards human 20S proteasome. This outcome suggests that the 1,2,3,4-tetrahydroisoquinoline skeleton may be exploited as a template for the development of novel anticancer agents. In this article, we report the synthesis and chemical characterization of a new series of isosalsoline-type alkaloids (10-11) with variations at N2 and C3 positions with respect to the natural Compound 2, obtained by a synthetic strategy that involves the Bischler-Napieralski cyclization. The substrate for the condensation to the tetrahydroisoquinoline system, i.e., a functionalized β-arylethyl amine, was obtained through an original double reduction of nitroalkene. The synthetic strategy can be directed to the construction of highly substituted and functionalized 1,2,3,4-tetrahydroisoquinolines. PMID:26287146

  20. Lipopolysaccharide-specific bacteriophage for Klebsiella pneumoniae C3.

    PubMed Central

    Tomás, J M; Jofre, J T

    1985-01-01

    Bacteriophage FC3-1 is one of several specific bacteriophages of Klebsiella pneumoniae C3 isolated in our laboratory. Unlike receptors for other Klebsiella phages, the bacteriophage FC3-1 receptor was shown to be lipopolysaccharide, specifically the polysaccharide fraction (O-antigen and core region). We concluded that capsular polysaccharide, outer membrane proteins, and lipid A were not involved in phage binding. Mutants resistant to this phage were isolated and were found to be devoid of lipopolysaccharide O-antigen by several criteria but to contain capsular material serologically identical to that of the wild type. The polysaccharide fraction was concluded to be the primary phage receptor, indicating that it is available to the phage. Images PMID:3888963

  1. Evaluation of effects of multiple candidate genes (LEP, LEPR, MC4R, PIK3C3, and VRTN) on production traits in Duroc pigs.

    PubMed

    Hirose, Kensuke; Ito, Tetsuya; Fukawa, Kazuo; Arakawa, Aisaku; Mikawa, Satoshi; Hayashi, Yoichi; Tanaka, Kazuaki

    2014-03-01

    We evaluated multiple effects of genetic variations of five candidate loci (LEP, LEPR, MC4R, PIK3C3 and VRTN) on four production traits (average daily weight gain (ADG); backfat thickness (BFT); loin eye muscle area (EMA); and intramuscular fat content (IMF)) in a closed nucleus herd of pure Duroc pigs. Polymorphisms in LEPR, MC4R and PIK3C3 had significant single gene effects on ADG and BFT. The additive genetic variance in ADG and BFT (16.99% and 22.51%, respectively) was explained by genetic effects of these three loci. No correlations were observed between the LEP genotype and production traits in this study. Although we detected marginally epistatic interactions between LEPR and PIK3C3 on the eye muscle area, there were no significant epistatic effects on any traits among all loci pairs. These results suggest that LEPR, MC4R, PIK3C3 and VRTN may independently influence growth rate and fat deposition. Furthermore, the statistical models for predicting the breeding values of each trait had the lowest Akaike's information criterion values when considering the effect of the MC4R, LEPR, PIK3C3 and VRTN genotype simultaneously. These results suggest that LEPR, MC4R, PIK3C3 and VRTN are useful markers for accurately predicting breeding values in Duroc pigs.

  2. New Laboratory Measurements of Rhomboidal SiC_3

    NASA Astrophysics Data System (ADS)

    Gottlieb, Carl A.; Thaddeus, Patrick

    2009-06-01

    Rhomboidal SiC_3, the highly polar planar ring with C_{2v} symmetry and a transannular C-C bond, was detected in our laboratory about 10 years ago, and soon afterwards was identified with a radio telescope in the expanding envelope of IRC+10216. Recently a sensitive spectral line survey of IRC+10216 was made with the Submillimeter Array (SMA) in the 300 - 355 GHz range with a 3^'' × 2^'' synthesized beam. Many new lines were detected in this survey. Most are from high rotational transitions of molecules that are known in IRC+10216, but some of the lines are quite narrow and more than 10 of these are unassigned. In support of the SMA observations we have extended the earlier laboratory measurements by Apponi et al. from 286 GHz and K_a ≤ 6, to 450 GHz and K_a ≤ 20 from rotational levels as high as 825 K above ground. As a result uncertainties in the predicted spectrum for lines with high K_a have been reduced by as much as two orders of magnitude, which should aid the assignment of SiC_3 in the SMA survey and in future observations with ALMA. A. J. Apponi, M. C. McCarthy, C. A. Gottlieb, and P. Thaddeus, Journ. Chem. Phys. 111, 3911 (1999). A. J. Apponi, M. C. McCarthy, C. A. Gottlieb, and P. Thaddeus, Astrophys. Journ. Lett. 516, L103 (1999). N. A. Patel, K. H. Young, S. Brünken, R. W. Wilson, P. Thaddeus, K. M. Menten, M. Reid, M. C. McCarthy, Dinh-V Trung, C. A. Gottlieb, and A. Hedden, Astrophys. Journ., in press (2009).

  3. Carbon Isotope Discrimination in Leaves of C3 Plants

    NASA Astrophysics Data System (ADS)

    Cuntz, M.; Gleixner, G.

    2009-04-01

    Carbon isotope composition is regarded as a powerful tool in understanding carbon cycling, both as a tracer and as a process recorder. However, accurate predictions of, for example, partitioning the net carbon flux into its components or obtaining climate information from tree rings, requires a good understanding of plant metabolism and related isotopic fractionations. Mechanistic models have concentrated largely on photosynthetic pathways and their isotopic composition. This cannot be said for respiratory processes. The mechanistic models of leaf isotope discrimination hence do not describe dawn, dusk and night very realistically or not at all. A new steady-state approach of the carbon isotope distribution in glucose potentially addresses the time of twilight and night (Tcherkez et al. 2004). Here, a new model of 13C discrimination in leaves of C3 plants is presented. The model is based on the steady-state approach of Tcherkez et al. (2004) but with much reduced complexity while retaining its general characteristics. In addition, the model introduces some new concepts such as a day-length dependent starch synthesis, night-length dependent starch degradation, energy-driven biosynthesis rates, and continuous leaf discrimination calculation for the whole diel cycle. It is therefore well adapted for biosphere-atmosphere exchange studies. The model predicts enriched sucrose and starch pools in the leaf compared to assimilated CO2. Biosynthesis on the other hand acts as the sink of the remaining, depleted carbon. The model calculates slightly different absolute starch compositions from the Tcherkez et al. (2004) model but this depends on chosen fractionation factors. The greatest difference between the two models is during dawn, dusk and night. For example, while Tcherkez et al. has changing phloem sucrose isotope composition during night, the model here predicts constant sucrose export composition. Observations seem to support rather constant phloem isotope composition

  4. C3: A Collaborative Web Framework for NASA Earth Exchange

    NASA Astrophysics Data System (ADS)

    Foughty, E.; Fattarsi, C.; Hardoyo, C.; Kluck, D.; Wang, L.; Matthews, B.; Das, K.; Srivastava, A.; Votava, P.; Nemani, R. R.

    2010-12-01

    The NASA Earth Exchange (NEX) is a new collaboration platform for the Earth science community that provides a mechanism for scientific collaboration and knowledge sharing. NEX combines NASA advanced supercomputing resources, Earth system modeling, workflow management, NASA remote sensing data archives, and a collaborative communication platform to deliver a complete work environment in which users can explore and analyze large datasets, run modeling codes, collaborate on new or existing projects, and quickly share results among the Earth science communities. NEX is designed primarily for use by the NASA Earth science community to address scientific grand challenges. The NEX web portal component provides an on-line collaborative environment for sharing of Eearth science models, data, analysis tools and scientific results by researchers. In addition, the NEX portal also serves as a knowledge network that allows researchers to connect and collaborate based on the research they are involved in, specific geographic area of interest, field of study, etc. Features of the NEX web portal include: Member profiles, resource sharing (data sets, algorithms, models, publications), communication tools (commenting, messaging, social tagging), project tools (wikis, blogs) and more. The NEX web portal is built on the proven technologies and policies of DASHlink.arc.nasa.gov, (one of NASA's first science social media websites). The core component of the web portal is a C3 framework, which was built using Django and which is being deployed as a common framework for a number of collaborative sites throughout NASA.

  5. Molecular Basis for Complement Recognition and Inhibition Determined by Crystallographic Studies of the Staphylococcal Complement Inhibitor (SCIN) Bound to C3c and C3b

    SciTech Connect

    Garcia, Brandon L.; Ramyar, Kasra X.; Tzekou, Apostolia; Ricklin, Daniel; McWhorter, William J.; Lambris, John D.; Geisbrecht, Brian V.

    2010-10-22

    The human complement system plays an essential role in innate and adaptive immunity by marking and eliminating microbial intruders. Activation of complement on foreign surfaces results in proteolytic cleavage of complement component 3 (C3) into the potent opsonin C3b, which triggers a variety of immune responses and participates in a self-amplification loop mediated by a multi-protein assembly known as the C3 convertase. The human pathogen Staphylococcus aureus has evolved a sophisticated and potent complement evasion strategy, which is predicated upon an arsenal of potent inhibitory proteins. One of these, the staphylococcal complement inhibitor (SCIN), acts at the level of the C3 convertase (C3bBb) and impairs downstream complement function by trapping the convertase in a stable but inactive state. Previously, we have shown that SCIN binds C3b directly and competitively inhibits binding of human factor H and, to a lesser degree, that of factor B to C3b. Here, we report the co-crystal structures of SCIN bound to C3b and C3c at 7.5 and 3.5 {angstrom} limiting resolution, respectively, and show that SCIN binds a critical functional area on C3b. Most significantly, the SCIN binding site sterically occludes the binding sites of both factor H and factor B. Our results give insight into SCIN binding to activated derivatives of C3, explain how SCIN can recognize C3b in the absence of other complement components, and provide a structural basis for the competitive C3b-binding properties of SCIN. In the future, this may suggest templates for the design of novel complement inhibitors based upon the SCIN structure.

  6. Climate Change Communicators: The C3E3 Project

    NASA Astrophysics Data System (ADS)

    Sharif, H. O.; Joseph, J.

    2013-12-01

    The University of Texas at San Antonio (UTSA), San Antonio College (SAC), and the University of North Dakota (UND) have partnered with NASA to provide underrepresented undergraduates from UTSA, SAC, and other community colleges climate-related research and education experiences through the Climate Change Communication: Engineer, Environmental science, and Education (C3E3) project. The program aims to develop a robust response to climate change by providing K-16 climate change education; enhance the effectiveness of K-16 education particularly in engineering and other STEM disciplines by use of new instructional technologies; increase the enrollment in engineering programs and the number of engineering degrees awarded by showing engineering's usefulness in relation to the much-discussed contemporary issue of climate change; increase persistence in STEM degrees by providing student research opportunities; and increase the ethnic diversity of those receiving engineering degrees and help ensure an ethnically diverse response to climate change. Students participated in the second summer internship funded by the project. More than 60 students participated in guided research experiences aligned with NASA Science Plan objectives for climate and Earth system science and the educational objectives of the three institutions. The students went through training in modern media technology (webcasts), and in using this technology to communicate the information on climate change to others, especially high school students, culminating in production of webcasts on investigating the aspects of climate change using NASA data. Content developed is leveraged by NASA Earth observation data and NASA Earth system models and tools. Several departments are involved in the educational program.

  7. Disaster Prevention Coastal Map Production by MMS & C3D

    NASA Astrophysics Data System (ADS)

    Hatake, Shuhei; Kohori, Yuki; Watanabe, Yasushi

    2016-06-01

    In March 2011, Eastern Japan suffered serious damage of Tsunami caused by a massive earthquake. In 2012, Ministry of Land, Infrastructure and Transport published "Guideline of setting assumed areas of inundation by Tsunami" to establish the conditions of topography data used for simulation of Tsunami. In this guideline, the elevation data prepared by Geographical Survey Institute of Japan and 2m/5m/10m mesh data of NSDI are adopted for land area, while 500m mesh data of Hydrographic and Oceanographic Department of Japan Coast Guard and sea charts are adopted for water area. These data, however, do not have continuity between land area and water area. Therefore, in order to study the possibility of providing information for coastal disaster prevention, we have developed an efficient method to acquire continuous topography over land and water including tidal zone. Land area data are collected by Mobile Mapping System (MMS) and water area depth data are collected by interferometry echo sounder (C3D), and both data are simultaneously acquired on a same boat. Elaborate point cloud data of 1m or smaller are expected to be used for realistic simulation of Tsunami waves going upstream around shoreline. Tests were made in Tokyo Bay (in 2014) and Osaka Bay (in 2015). The purpose the test in Osaka Bay is to make coastal map for disaster prevention as a countermeasure for predicted Nankai massive earthquake. In addition to Tsunami simulation, the continuous data covering land and marine areas are expected to be used effectively for maintenance and repair of aged port and river facilities, maintenance and investigation of dykes, and ecosystem preservation.

  8. Polymorphous computing fabric

    DOEpatents

    Wolinski, Christophe Czeslaw; Gokhale, Maya B.; McCabe, Kevin Peter

    2011-01-18

    Fabric-based computing systems and methods are disclosed. A fabric-based computing system can include a polymorphous computing fabric that can be customized on a per application basis and a host processor in communication with said polymorphous computing fabric. The polymorphous computing fabric includes a cellular architecture that can be highly parameterized to enable a customized synthesis of fabric instances for a variety of enhanced application performances thereof. A global memory concept can also be included that provides the host processor random access to all variables and instructions associated with the polymorphous computing fabric.

  9. Technology For Command, Control, Communications And Intelligence (C3I)

    NASA Astrophysics Data System (ADS)

    Burgess, John S.

    1980-02-01

    I am happy to be here this morning with this distinguished technical audience of the Society of Photo-Optical Instrumentation Engineers. You have recognized a very important problem area and I think that through this conference or seminar, you will address many technical aspects of the problems associated with Command, Control, Communications and Intelligence (C³I). C³I is a term that is gaining more and more visibility and acceptance in all areas of military operations. In the past, the transfer of technology into military operations has been concentrated on force effectiveness. Our leaders now recognize more fully that force effectiveness depends to a very high degree on the command and control functions which in turn need to know the status of enemy as well as friendly forces. Perhaps the best way to start this discussion of C³I is to arrive at a definition. Unfortunately, I'm sure that if I ask each of you to give me a definition of C³I, I would have just as many definitions as there are people in the audience. The situation is similar to the old story about the three blind men trying to describe an elephant. I would like to paraphrase a few remarks of Julian Lake in a recent editorial in Military Electronics/Countermeasures Magazine. As he points out, C3 is many things to many people. To the intelligence specialist who is so wrapped up in his intelligence community activity, C³I is simply an extension of the modern applications of intelligence. In fact, the intelligence officer feels that he is the actual center of the C³I structure. On the other hand, the communications specialist thinks that communications is the actual heartbeat of C³I activity, and this is right to a point because communications is a fundamental building block of the C3 function. The computer specialist will point out that C³I is merely a product of the computer age. One reason there was very little done about C³I in the past was the nonavailability of computer techniques and

  10. Complement (C3) metabolism in systemic lupus erythematosus in relation to the disease course.

    PubMed

    Swaak, A J; van Rooyen, A; Vogelaar, C; Pillay, M; Hack, E

    1986-01-01

    Metabolic turnover studies of complement components (C3) provide a direct insight into the dynamics of the complement regulation (synthesis and catabolism). To obtain information about the role of the complement system in relation to the disease course in patients with systemic lupus erythematosus (SLE), a prospective study was performed. The results of the C3 turnover studies were also correlated to the complement levels (C3) and to the presence of C3 conversion products (C3d) in circulation. In nearly all SLE patients (in 21 of the 26 metabolic turnover studies) a C3 hypercatabolism was found, with a quantitative difference depending on the disease phase. In the period preceding an exacerbation an impaired C3 synthesis was observed (in three of the four studies), in contrast to SLE patients in stable disease phase where in one case only a decrease C3 synthesis was calculated (1 out of 15 observations). A linear correlation was found between the serum C3-levels and the ratio of C3d/C3, suggesting that both serologic parameters are quantitatively indicative for C3 hypercatabolism. The study shows that in all SLE patients, irrespective of the disease stage, an increased C3 consumption is found, which supports the concept that a chronic inflammatory process is constantly present.

  11. 21 CFR 866.5260 - Complement C3b inactivator immunological test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... immunochemical techniques the complement C3b inactivator (a plasma protein) in serum. Complement is a group of serum proteins that destroy infectious agents. Measurement of complement C3b inactivator aids in...

  12. 21 CFR 866.5260 - Complement C3b inactivator immunological test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... immunochemical techniques the complement C3b inactivator (a plasma protein) in serum. Complement is a group of serum proteins that destroy infectious agents. Measurement of complement C3b inactivator aids in...

  13. 21 CFR 866.5260 - Complement C3b inactivator immunological test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... immunochemical techniques the complement C3b inactivator (a plasma protein) in serum. Complement is a group of serum proteins that destroy infectious agents. Measurement of complement C3b inactivator aids in...

  14. 21 CFR 866.5260 - Complement C3b inactivator immunological test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... immunochemical techniques the complement C3b inactivator (a plasma protein) in serum. Complement is a group of serum proteins that destroy infectious agents. Measurement of complement C3b inactivator aids in...

  15. Human complement C3 deficiency: Th1 induction requires T cell-derived complement C3a and CD46 activation.

    PubMed

    Ghannam, Arije; Fauquert, Jean-Luc; Thomas, Caroline; Kemper, Claudia; Drouet, Christian

    2014-03-01

    Human T helper type 1 (Th1) responses are essential in defense. Although T cell receptor (TCR) and co-stimulator engagement are indispensable for T cell activation, stimulation of additional receptor pathways are also necessary for effector induction. For example, engagement of the complement regulator CD46 by its ligand C3b generated upon TCR activation is required for IFN-γ production as CD46-deficient patients lack Th1 responses. Utilizing T cells from two C3-deficient patients we demonstrate here that normal Th1 responses also depend on signals mediated by the anaphylatoxin C3a receptor (C3aR). Importantly, and like in CD46-deficient patients, whilst Th1 induction are impaired in C3-deficient patients in vitro, their Th2 responses are unaffected. Furthermore, C3-deficient CD4(+) T cells present with reduced expression of CD25 and CD122, further substantiating the growing notion that complement fragments regulate interleukin-2 receptor (IL-2R) assembly and that disturbance of complement-guided IL-2R assembly contributes to aberrant Th1 effector responses. Lastly, sustained intrinsic production of complement fragments may participate in the Th1 contraction phase as both C3a and CD46 engagement regulate IL-10 co-expression in Th1 cells. These data suggest that C3aR and CD46 activation via intrinsic generation of their respective ligands is an integral part of human Th1 (but not Th2) immunity. PMID:24321396

  16. Characterization of the third component of complement (C3) after activation by cigarette smoke

    SciTech Connect

    Kew, R.R.; Ghebrehiwet, B.; Janoff, A.

    1987-08-01

    Activation of lung complement by tobacco smoke may be an important pathogenetic factor in the development of pulmonary emphysema in smokers. We previously showed that cigarette smoke can modify C3 and activate the alternative pathway of complement in vitro. However, the mechanism of C3 activation was not fully delineated in these earlier studies. In the present report, we show that smoke-treated C3 induces cleavage of the alternative pathway protein, Factor B, when added to serum containing Mg-EGTA. This effect of cigarette smoke is specific for C3 since smoke-treated C4, when added to Mg-EGTA-treated serum, fails to activate the alternative pathway and fails to induce Factor B cleavage. Smoke-modified C3 no longer binds significant amounts of (/sup 14/C)methylamine (as does native C3), and relatively little (/sup 14/C)methylamine is incorporated into its alpha-chain. Thus, prior internal thiolester bond cleavage appears to have occurred in C3 activated by cigarette smoke. Cigarette smoke components also induce formation of noncovalently associated, soluble C3 multimers, with a Mr ranging from 1 to 10 million. However, prior cleavage of the thiolester bond in C3 with methylamine prevents the subsequent formation of these smoke-induced aggregates. These data indicate that cigarette smoke activates the alternative pathway of complement by specifically modifying C3 and that these modifications include cleavage of the thiolester bond in C3 and formation of noncovalently linked C3 multimers.

  17. 17 CFR 240.14c-3 - Annual report to be furnished security holders.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... security holders. 240.14c-3 Section 240.14c-3 Commodity and Securities Exchanges SECURITIES AND EXCHANGE... Section 14(c) § 240.14c-3 Annual report to be furnished security holders. (a) If the information statement... such meeting, of security holders at which directors of the registrant, other than an...

  18. Complement (C3) metabolism in rheumatoid arthritis in relation to the disease course.

    PubMed

    Swaak, A J; Han, H; van Rooyen, A; Pillay, M; Hack, C E

    1988-01-01

    Metabolic turnover studies of the third component of complement, C3, were performed in 23 patients with rheumatoid arthritis (RA) to get a direct insight in the dynamics of complement synthesis and catabolism. Results of these turnover studies were related to the serum level of the total amount of C3 as well as to that of the activation product C3d. A hypercatabolism of C3 was observed in 12 of the 23 patients studied. Six of these 12 patients showed signs of extra-articular RA; only one patient with extra-articular manifestations had a normal catabolism of C3. Decreased serum levels of C3 were not found in any of the patients with a hypercatabolism of C3, indicating that the accelerated turnover was compensated by an increased synthesis. In RA patients levels of the activation product C3d could not correlate with the turnover of C3. However, in selected RA patients without signs of nodules or extra-articular manifestations, they could. Thus, our results indicate that serum levels of C3 and C3d do not reflect C3 metabolism in RA patients. Furthermore, the existence of extra-articular manifestations is accompanied by a more pronounced activation of the complement system.

  19. 17 CFR 240.14c-3 - Annual report to be furnished security holders.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... security holders. 240.14c-3 Section 240.14c-3 Commodity and Securities Exchanges SECURITIES AND EXCHANGE... Section 14(c) § 240.14c-3 Annual report to be furnished security holders. (a) If the information statement... such meeting, of security holders at which directors of the registrant, other than an...

  20. 17 CFR 274.221 - Form N-23c-3, Notification of repurchase offer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... chapter). Editorial Note: For Federal Register citations affecting Form N-23c-3, see the List of CFR... repurchase offer. 274.221 Section 274.221 Commodity and Securities Exchanges SECURITIES AND EXCHANGE... § 274.221 Form N-23c-3, Notification of repurchase offer. Form N-23c-3 shall be filed with copies...

  1. 17 CFR 274.221 - Form N-23c-3, Notification of repurchase offer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... chapter). Editorial Note: For Federal Register citations affecting Form N-23c-3, see the List of CFR... repurchase offer. 274.221 Section 274.221 Commodity and Securities Exchanges SECURITIES AND EXCHANGE... § 274.221 Form N-23c-3, Notification of repurchase offer. Form N-23c-3 shall be filed with copies...

  2. Characterization of the third component of complement (C3) after activation by cigarette smoke.

    PubMed

    Kew, R R; Ghebrehiwet, B; Janoff, A

    1987-08-01

    Activation of lung complement by tobacco smoke may be an important pathogenetic factor in the development of pulmonary emphysema in smokers. We previously showed that cigarette smoke can modify C3 and activate the alternative pathway of complement in vitro. However, the mechanism of C3 activation was not fully delineated in these earlier studies. In the present report, we show that smoke-treated C3 induces cleavage of the alternative pathway protein, Factor B, when added to serum containing Mg-EGTA. This effect of cigarette smoke is specific for C3 since smoke-treated C4, when added to Mg-EGTA-treated serum, fails to activate the alternative pathway and fails to induce Factor B cleavage. Smoke-modified C3 no longer binds significant amounts of [14C]methylamine (as does native C3), and relatively little [14C]methylamine is incorporated into its alpha-chain. Thus, prior internal thiolester bond cleavage appears to have occurred in C3 activated by cigarette smoke. Cigarette smoke components also induce formation of noncovalently associated, soluble C3 multimers, with a Mr ranging from 1 to 10 million. However, prior cleavage of the thiolester bond in C3 with methylamine prevents the subsequent formation of these smoke-induced aggregates. These data indicate that cigarette smoke activates the alternative pathway of complement by specifically modifying C3 and that these modifications include cleavage of the thiolester bond in C3 and formation of noncovalently linked C3 multimers.

  3. Hydrogen storage in C3Ti complex using quantum chemical methods and molecular dynamics simulations.

    PubMed

    Kalamse, Vijayanand; Wadnerkar, Nitin; Chaudhari, Ajay

    2012-06-01

    The hydrogen storage capacity of C(3)Ti and C(3)Ti(+) complex was studied using second order Møller-Plesset (MP2) and density functional theory (DFT) methods with different exchange and correlation functionals. Four and five H(2) molecules can be adsorbed on C(3)Ti and C(3)Ti(+) complex respectively at all the levels of theory used. This corresponds to the gravimetric H(2) uptake capacity of 8.77 and 10.73 wt % for the former and the latter respectively. The nature of interactions between different molecules in H(2) adsorbed complexes is also studied using many-body analysis approach. In the case of C(3)Ti(4H(2)) complex, total five-body interactions is negligible whereas for C(3)Ti(+)(5H(2)) relaxation energy is negligible. All the many-body energies have significant contribution to the binding energy of a respective complex. Atom-centered density matrix propagation molecular dynamics simulations were carried out using different methods to confirm whether H(2) molecules remain adsorbed on C(3)Ti and C(3)Ti(+) complex at room temperature. Adsorption Gibbs free energies show that four and five H(2) molecule adsorption on C(3)Ti and C(3)Ti(+) at room temperature is energetically favorable and unfavorable respectively using MP2 as well as DFT methods used here. H(2) adsorption is thermodynamically favorable over a wide range of temperature on the C(3)Ti than C(3)Ti(+)complex.

  4. The C3 Framework: One Year Later - an Interview with Kathy Swan

    ERIC Educational Resources Information Center

    Social Education, 2014

    2014-01-01

    On September 17, 2013 (Constitution Day), the C3 Framework was released under the title "The College, Career and Civic Life (C3) Framework for Social Studies State Standards: Guidance for Enhancing the Rigor of K-12 Civics, Economics, Geography, and History." The C3 Project Director and lead writer was NCSS member Kathy Swan, who is…

  5. 18 CFR 3c.3 - Reporting fraud, waste, abuse, and corruption and cooperation with official inquiries.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... OF CONDUCT § 3c.3 Reporting fraud, waste, abuse, and corruption and cooperation with official inquiries. (a) Employees shall, in fulfilling the obligation of 5 CFR 2635.101(b)(11), report fraud, waste..., abuse, and corruption and cooperation with official inquiries. 3c.3 Section 3c.3 Conservation of...

  6. 18 CFR 3c.3 - Reporting fraud, waste, abuse, and corruption and cooperation with official inquiries.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... OF CONDUCT § 3c.3 Reporting fraud, waste, abuse, and corruption and cooperation with official inquiries. (a) Employees shall, in fulfilling the obligation of 5 CFR 2635.101(b)(11), report fraud, waste..., abuse, and corruption and cooperation with official inquiries. 3c.3 Section 3c.3 Conservation of...

  7. 17 CFR 270.6c-3 - Exemptions for certain registered variable life insurance separate accounts.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... registered variable life insurance separate accounts. 270.6c-3 Section 270.6c-3 Commodity and Securities... 1940 § 270.6c-3 Exemptions for certain registered variable life insurance separate accounts. A separate account which meets the requirements of paragraph (a) of Rule 6e-2 (17 CFR 270.6e-2) or paragraph (a)...

  8. Detection of complement activation using monoclonal antibodies against C3d

    PubMed Central

    Thurman, Joshua M.; Kulik, Liudmila; Orth, Heather; Wong, Maria; Renner, Brandon; Sargsyan, Siranush A.; Mitchell, Lynne M.; Hourcade, Dennis E.; Hannan, Jonathan P.; Kovacs, James M.; Coughlin, Beth; Woodell, Alex S.; Pickering, Matthew C.; Rohrer, Bärbel; Holers, V. Michael

    2013-01-01

    During complement activation the C3 protein is cleaved, and C3 activation fragments are covalently fixed to tissues. Tissue-bound C3 fragments are a durable biomarker of tissue inflammation, and these fragments have been exploited as addressable binding ligands for targeted therapeutics and diagnostic agents. We have generated cross-reactive murine monoclonal antibodies against human and mouse C3d, the final C3 degradation fragment generated during complement activation. We developed 3 monoclonal antibodies (3d8b, 3d9a, and 3d29) that preferentially bind to the iC3b, C3dg, and C3d fragments in solution, but do not bind to intact C3 or C3b. The same 3 clones also bind to tissue-bound C3 activation fragments when injected systemically. Using mouse models of renal and ocular disease, we confirmed that, following systemic injection, the antibodies accumulated at sites of C3 fragment deposition within the glomerulus, the renal tubulointerstitium, and the posterior pole of the eye. To detect antibodies bound within the eye, we used optical imaging and observed accumulation of the antibodies within retinal lesions in a model of choroidal neovascularization (CNV). Our results demonstrate that imaging methods that use these antibodies may provide a sensitive means of detecting and monitoring complement activation–associated tissue inflammation. PMID:23619360

  9. The C3-bending vibrational levels of the C3-Kr and C3-Xe van der Waals complexes studied by their Ã-X̃ electronic transitions and by ab initio calculations.

    PubMed

    Chao, Jun-Mei; Tham, Keng Seng; Zhang, Guiqiu; Merer, Anthony J; Hsu, Yen-Chu; Hu, Wei-Ping

    2011-02-21

    Fluorescence excitation spectra and wavelength-resolved emission spectra of the C(3)-Kr and C(3)-Xe van der Waals (vdW) complexes have been recorded near the 2(2-)(0), 2(2+)(0), 2(4-)(0), and 1(1)(0) bands of the Ã(1)Π(u)-X̃(1)Σ(g)(+) system of the C(3) molecule. In the excitation spectra, the spectral features of the two complexes are red-shifted relative to those of free C(3) by 21.9-38.2 and 34.3-36.1 cm(-1), respectively. The emission spectra from the à state of the Kr complex consist of progressions in the two C(3)-bending vibrations (ν(2), ν(4)), the vdW stretching (ν(3)), and bending vibrations (ν(6)), suggesting that the equilibrium geometry in the X̃ state is nonlinear. As in the Ar complex [Zhang et al., J. Chem. Phys. 120, 3189 (2004)], the C(3)-bending vibrational levels of the Kr complex shift progressively to lower energy with respect to those of free C(3) as the bending quantum number increases. Their vibrational structures could be modeled as perturbed harmonic oscillators, with the dipole-induced dipole terms of the Ar and Kr complexes scaled roughly by the polarizabilities of the Ar and Kr atoms. Emission spectra of the Xe complex, excited near the Ã, 2(2-) level of free C(3), consist only of progressions in even quanta of the C(3)-bending and vdW modes, implying that the geometry in the higher vibrational levels (υ(bend) ≥ 4, E(vib) ≥ 328 cm(-1)) of the X̃ state is (vibrationally averaged) linear. In this structure the Xe atom bonds to one of the terminal carbons nearly along the inertial a-axis of bent C(3). Our ab initio calculations of the Xe complex at the level of CCSD(T)∕aug-cc-pVTZ (C) and aug-cc-pVTZ-PP (Xe) predict that its equilibrium geometry is T-shaped (as in the Ar and Kr complexes), and also support the assignment of a stable linear isomer when the amplitude of the C(3) bending vibration is large (υ(4) ≥ 4).

  10. A circulating inhibitor of fluid-phase amplification. C3 convertase formation in systemic lupus erythematosus.

    PubMed Central

    Waldo, F B; Forristal, J; Beischel, L; West, C D

    1985-01-01

    C3 nephritic factor (C3NeF) was used to assess the formation of the fluid-phase amplification convertase, C3b,Bb, in 37 serum specimens from 24 patients with systemic lupus erythematosus (SLE). C3b,Bb formation was measured by the concentration of Ba, released when C3b,B is activated. Incubation of normal human serum (NHS) with C3NeF accelerates C3b amplification loop turnover with the formation of large quantities of C3b,Bb. In contrast, sera from 22 of 24 patients with SLE formed little or no convertase when incubated with C3NeF. C3 conversion to C3b was commensurately reduced. The inhibition could not be attributed to depressed serum concentrations of C3, factor B, or classical pathway components. Inhibitor present in excess could be demonstrated in 23 of 34 specimens of SLE serum by mixing experiments. The spontaneous convertase formation that occurs when a portion of the serum H is inactivated with F(ab')2 anti-H was also shown to be inhibited in SLE serum. The inhibition was found, however, to be H dependent in that convertase formation was normal in SLE serum depleted of H. It is concluded that the C3b in most SLE sera is unusually susceptible to inactivation by H, but a functional abnormality was not demonstrable in either C3 or H isolated from SLE serum. The inhibition could be simulated in NHS by addition of heparin, 100 micrograms/ml. In vivo, inhibition of convertase formation could interfere with the solubilization and disposal of immune complexes by reducing the deposition of C3b on the immune complex lattice. PMID:3159752

  11. Complement C3 is expressed by mast cells in cutaneous vasculitis and is degraded by chymase.

    PubMed

    Lipitsä, Tiina; Naukkarinen, Anita; Laitala, Joel; Harvima, Ilkka T

    2016-10-01

    The complement factor C3 and chymase released from tryptase(+), chymase(+) mast cells may be involved in the pathogenesis of cutaneous leukocytoclastic vasculitis. To study whether mast cells contain C3 in vasculitis and whether chymase interacts with C3, cryosections from vasculitis biopsies were double-stained histochemically for C3c in tryptase(+) mast cells, as well as for chymase and vessel wall C3c, or they were treated with 5 µg/ml rh-chymase for 24 h followed by immunofluorescence (IF) analysis of C3c, IgG, IgM and IgA. The effect of rh-chymase on purified human C3, C3a and IgG was studied using SDS-PAGE electrophoresis and LAD2 mast cell cultures. The results show that 34.2 ± 17.9, 37.4 ± 15.5 and 43.4 ± 18.6 % (mean ± SD) of the mast cells express C3c immunoreactivity in the healthy skin, initial petechial (IP) and palpable purpura (PP) lesions, respectively. About 9.4-12.1 % of the chymase(+) mast cells were in apparent contact with C3c(+) vessels in IP and PP. The treatment of cryosections with rh-chymase decreased the IF staining of C3c, but not that of immunoglobulins. In SDS-PAGE, 1-10 µg/ml rh-chymase degraded the alpha- and beta-chains of C3, but did not degrade IgG. Unexpectedly, the rh-chymase treatment of C3 produced fragments that resulted in the release of tryptase and histamine from LAD2 cells. However, rh-chymase degraded C3a and consequently inhibited C3a activity on LAD2. In conclusion, mast cells can be one source for C3 in the early and late phases of vasculitis pathogenesis. However, rh-chymase degraded native C3, vessel wall C3c, and biologically active C3a. Therefore, chymase may control C3-related pathology. PMID:27465068

  12. Characterization of a C3a receptor in rainbow trout and Xenopus: the first identification of C3a receptors in nonmammalian species

    USGS Publications Warehouse

    Boshra, Hani; Wang, Tiehui; Hove-Madsen, Leif; Hansen, John D.; Li, Jun; Matlapudi, Anjun; Secombes, Christopher J.; Tort, Lluis; Sunyer, J. Oriol

    2005-01-01

    Virtually nothing is known about the structure, function, and evolutionary origins of the C3aR in nonmammalian species. Because C3aR and C5aR are thought to have arisen from the same common ancestor, the recent characterization of a C5aR in teleost fish implied the presence of a C3aR in this animal group. In this study we report the cloning of a trout cDNA encoding a 364-aa molecule (TC3aR) that shows a high degree of sequence homology and a strong phylogenetic relationship with mammalian C3aRs. Northern blotting demonstrated that TC3aR was expressed primarily in blood leukocytes. Flow cytometric analysis and immunofluorescence microscopy showed that Abs raised against TC3aR stained to a high degree all blood B lymphocytes and, to a lesser extent, all granulocytes. More importantly, these Abs inhibited trout C3a-mediated intracellular calcium mobilization in trout leukocytes. A fascinating structural feature of TC3aR is the lack of a significant portion of the second extracellular loop (ECL2). In all C3aR molecules characterized to date, the ECL2 is exceptionally large when compared with the same region of C5aR. However, the exact function of the extra portion of ECL2 is unknown. The lack of this segment in TC3aR suggests that the extra piece of ECL2 was not necessary for the interaction of the ancestral C3aR with its ligand. Our findings represent the first C3aR characterized in nonmammalian species and support the hypothesis that if C3aR and C5aR diverged from a common ancestor, this event occurred before the emergence of teleost fish.

  13. Improvement of g-C3N4 photocatalytic properties using the Hummers method.

    PubMed

    Feng, Jing; Chen, Tingting; Liu, Shenna; Zhou, Qihang; Ren, Yueming; Lv, Yanzhuo; Fan, Zhuangjun

    2016-10-01

    In this study, graphitic C3N4 (g-C3N4) with high photocatalytic properties to methylene blue (MB) was synthesized by treating the bulk g-C3N4 using the Hummers method. The bulk g-C3N4 was obtained by calcining dicyandiamide. The g-C3N4 treated by the Hummers method (E-g-C3N4) was characterized and utilized for the photocatalytic removal of MB. The results showed that the Hummers treatment exfoliated the nanosheets bulk g-C3N4 into nanorods and improved the dispersion of E-g-C3N4 in an aqueous solution. It also distinctly enhanced the photocatalytic activity of g-C3N4 to MB, i.e., the removal efficiency increased from 38.45% for the bulk g-C3N4 to 96.61% for the E-g-C3N4.

  14. Biological Control of Bipolaris sorokiniana on Tall Fescue by Stenotrophomonas maltophilia Strain C3.

    PubMed

    Zhang, Z; Yuen, G Y

    1999-09-01

    ABSTRACT Stenotrophomonas maltophilia strain C3 was evaluated for control of leaf spot on tall fescue (Festuca arundinacea) caused by Bipolaris sorokiniana. In growth chamber experiments, C3 inhibited conidial germination on leaf surfaces and reduced lesion frequency and percent diseased leaf area compared with nontreated controls. The amount of leaf spot suppression was related to the C3 dose applied. The highest dose tested, 10(9) CFU/ml, prevented nearly all B. sorokiniana conidia from germinating on treated leaf surfaces and provided nearly complete suppression of lesion development. When colloidal chitin was added to C3 cell suspensions of 10(7) or 10(8) CFU/ml, biocontrol efficacy was significantly increased over C3 applied alone, whereas addition of chitin to a C3 cell suspension of 10(9) CFU/ml had no effect. In field experiments, application of C3 to tall fescue turf resulted in significant reductions in infection frequency and disease severity compared with nontreated controls. Strain C3 applied at 10(9) CFU/ml was more effective than C3 applied at 10(7) CFU/ml, and amendment of the lower dose with colloidal chitin enhanced its efficacy. Populations sizes of C3 established on foliage in a growth chamber and in the field were directly related to dose applied. Chitin amendments did not affect C3 population size.

  15. Complement C3 gene: Expression characterization and innate immune response in razor clam Sinonovacula constricta.

    PubMed

    Peng, Maoxiao; Niu, Donghong; Wang, Fei; Chen, Zhiyi; Li, Jiale

    2016-08-01

    Complement component 3 (C3) is central to the complement system, playing an important role in immune defense, immune regulation and immune pathology. Several C3 genes have been characterized in invertebrates but very few in shellfish. The C3 gene was identified from the razor clam Sinonovacula constricta, referred to here as Sc-C3. It was found to be highly homologous with the C3 gene of Ruditapes decussatus. All eight model motifs of the C3 gene were found to be included in the thiolester bond and the C345C region. Sc-C3 was widely expressed in all healthy tissues with expression being highest in hemolymph. A significant difference in expression was revealed at the umbo larvae development stage. The expression of Sc-C3 was highly regulated in the hemolymph and liver, with a distinct response pattern being noted after a challenge with Micrococcus lysodeikticus and Vibrio parahemolyticus. It is therefore suggested that a complicated and unique response pathway may be present in S. constricta. Further, serum of S. constricta containing Sc-C3 was extracted. This was activated by LPS or bacterium for verification for function. The more obvious immune function of Sc-C3 was described as an effective membrane rupture in hemocyte cells of rabbit, V. parahemolyticus and Vibrio anguillarum. Thus, Sc-C3 plays an essential role in the immune defense of S. constricta. PMID:27231190

  16. Metabolism of radio-labelled C3: effects of in vivo activation in rabbits

    PubMed Central

    Charlesworth, J. A.; Williams, D. G.; Naish, P.; Lachmann, P. J.; Peters, D. K.

    1974-01-01

    Turnover studies were performed in rabbits using biologically screened, highly purified, radio-labelled human C3 and C3c. Experiments were also carried out using agents known to activate the complement system in vivo—cobra venom factor, human nephritic serum and nephrotoxic antibody to rabbit glomerular basement membrane. Activation of labelled C3 by cobra factor provided information regarding the metabolic behaviour of C3d. The fractional catabolic ratio (FCR) of human C3 in normal rabbits was 2·4–2·8% of the plasma pool per hr. FCR for C3c was 4.5% per hr. Activation of C3 in vivo consistently resulted in accelerated disappearance of plasma radioactivity. Analysis of the plasma and total body radioactivity curves indicated that both hypercatabolism and extravascular sequestration of radioactivity were responsible for this phenomenon. PMID:4468849

  17. Eculizumab-induced reversal of dialysis-dependent kidney failure from C3 glomerulonephritis

    PubMed Central

    Inman, Melissa; Prater, Ginnie; Fatima, Huma; Wallace, Eric

    2015-01-01

    C3 glomerulopathy (C3G) is characterized by C3 deposits with minimal immunoglobulin deposition caused by alternative complement pathway dysregulation. Unfortunately, no therapeutic intervention has consistently improved outcomes for patients with C3G. Eculizumab, a monoclonal antibody to C5, is currently the only approved complement-specific agent with some efficacy in the treatment of C3 glomerulonephritis (C3GN). Here, we describe a patient with acute crescentic C3GN with no identified complement mutation or family history of renal disease who required dialysis for 6 months. Five months after initiation of eculizumab, she became dialysis independent, showing improvement is possible after adequate time on eculizumab. PMID:26251714

  18. Highly Unsaturated Platinum and Palladium Carbenes PtC3 and PdC3 Isolated and Characterized in the Gas Phase

    PubMed Central

    Bittner, Dror M.; Zaleski, Daniel P.; Tew, David P.

    2016-01-01

    Abstract Carbenes of platinum and palladium, PtC3 and PdC3, were generated in the gas phase through laser vaporization of a metal target in the presence of a low concentration of a hydrocarbon precursor undergoing supersonic expansion. Rotational spectroscopy and ab initio calculations confirm that both molecules are linear. The geometry of PtC3 was accurately determined by fitting to the experimental moments of inertia of twenty‐six isotopologues. The results are consistent with the proposal of an autogenic isolobal relationship between O, Au+, and Pt atoms. PMID:27478275

  19. Highly Unsaturated Platinum and Palladium Carbenes PtC3 and PdC3 Isolated and Characterized in the Gas Phase

    PubMed Central

    Bittner, Dror M.; Zaleski, Daniel P.; Tew, David P.

    2016-01-01

    Abstract Carbenes of platinum and palladium, PtC3 and PdC3, were generated in the gas phase through laser vaporization of a metal target in the presence of a low concentration of a hydrocarbon precursor undergoing supersonic expansion. Rotational spectroscopy and ab initio calculations confirm that both molecules are linear. The geometry of PtC3 was accurately determined by fitting to the experimental moments of inertia of twenty‐six isotopologues. The results are consistent with the proposal of an autogenic isolobal relationship between O, Au+, and Pt atoms. PMID:26879473

  20. Highly Unsaturated Platinum and Palladium Carbenes PtC3 and PdC3 Isolated and Characterized in the Gas Phase

    DOE PAGES

    Bittner, Dror M.; Zaleski, Daniel P.; Tew, David P.; Walker, Nicholas R.; Legon, Anthony C.

    2016-02-16

    Carbenes of platinum and palladium, PtC3 and PdC3 , were generated in the gas phase through laser vaporization of a metal target in the presence of a low concentration of a hydrocarbon precursor undergoing supersonic expansion. Rotational spectroscopy and abinitio calculations confirm that both molecules are linear. The geometry of PtC3 was accurately determined by fitting to the experimental moments of inertia of twenty-six isotopologues. In conclusion, the results are consistent with the proposal of an autogenic isolobal relationship between O, Au+ , and Ptatoms.

  1. Mutational analysis of the complement receptor type 2 (CR2/CD21)-C3d interaction reveals a putative charged SCR1 binding site for C3d.

    PubMed

    Hannan, Jonathan P; Young, Kendra A; Guthridge, Joel M; Asokan, Rengasamy; Szakonyi, Gerda; Chen, Xiaojiang S; Holers, V Michael

    2005-02-25

    We have characterized the interaction between the first two short consensus repeats (SCR1-2) of complement receptor type 2 (CR2, CD21) and C3d in solution, by utilising the available crystal structures of free and C3d-bound forms of CR2 to create a series of informative mutations targeting specific areas of the CR2-C3d complex. Wild-type and mutant forms of CR2 were expressed on the surface of K562 erythroleukemia cells and their binding ability assessed using C3dg-biotin tetramers complexed to fluorochrome conjugated streptavidin and measured by flow cytometry. Mutations directed at the SCR2-C3d interface (R83A, R83E, G84Y) were found to strongly disrupt C3dg binding, supporting the conclusion that the SCR2 interface reflected in the crystal structure is correct. Previous epitope and peptide mapping studies have also indicated that the PILN11GR13IS sequence of the first inter-cysteine region of SCR1 is essential for the binding of iC3b. Mutations targeting residues within or in close spatial proximity to this area (N11A, N11E, R13A, R13E, Y16A, S32A, S32E), and a number of other positively charged residues located primarily on a contiguous face of SCR1 (R28A, R28E, R36A, R36E, K41A, K41E, K50A, K50E, K57A, K57E, K67A, K67E), have allowed us to reassess those regions on SCR1 that are essential for CR2-C3d binding. The nature of this interaction and the possibility of a direct SCR1-C3d association are discussed extensively. Finally, a D52N mutant was constructed introducing an N-glycosylation sequence at an area central to the CR2 dimer interface. This mutation was designed to disrupt the CR2-C3d interaction, either directly through steric inhibition, or indirectly through disruption of a physiological dimer. However, no difference in C3dg binding relative to wild-type CR2 could be observed for this mutant, suggesting that the dimer may only be found in the crystal form of CR2.

  2. Mutational analysis of the complement receptor type 2 (CR2/CD21)-C3d interaction reveals a putative charged SCR1 binding site for C3d.

    PubMed

    Hannan, Jonathan P; Young, Kendra A; Guthridge, Joel M; Asokan, Rengasamy; Szakonyi, Gerda; Chen, Xiaojiang S; Holers, V Michael

    2005-02-25

    We have characterized the interaction between the first two short consensus repeats (SCR1-2) of complement receptor type 2 (CR2, CD21) and C3d in solution, by utilising the available crystal structures of free and C3d-bound forms of CR2 to create a series of informative mutations targeting specific areas of the CR2-C3d complex. Wild-type and mutant forms of CR2 were expressed on the surface of K562 erythroleukemia cells and their binding ability assessed using C3dg-biotin tetramers complexed to fluorochrome conjugated streptavidin and measured by flow cytometry. Mutations directed at the SCR2-C3d interface (R83A, R83E, G84Y) were found to strongly disrupt C3dg binding, supporting the conclusion that the SCR2 interface reflected in the crystal structure is correct. Previous epitope and peptide mapping studies have also indicated that the PILN11GR13IS sequence of the first inter-cysteine region of SCR1 is essential for the binding of iC3b. Mutations targeting residues within or in close spatial proximity to this area (N11A, N11E, R13A, R13E, Y16A, S32A, S32E), and a number of other positively charged residues located primarily on a contiguous face of SCR1 (R28A, R28E, R36A, R36E, K41A, K41E, K50A, K50E, K57A, K57E, K67A, K67E), have allowed us to reassess those regions on SCR1 that are essential for CR2-C3d binding. The nature of this interaction and the possibility of a direct SCR1-C3d association are discussed extensively. Finally, a D52N mutant was constructed introducing an N-glycosylation sequence at an area central to the CR2 dimer interface. This mutation was designed to disrupt the CR2-C3d interaction, either directly through steric inhibition, or indirectly through disruption of a physiological dimer. However, no difference in C3dg binding relative to wild-type CR2 could be observed for this mutant, suggesting that the dimer may only be found in the crystal form of CR2. PMID:15713467

  3. Re-Analysis of the Dispersed Fluorescence Spectra of the C_3-RARE Gas Atom Complexes

    NASA Astrophysics Data System (ADS)

    Wang, Yi-Jen; Merer, Anthony; Hsu, Yen-Chu

    2015-06-01

    The dispersed fluorescence (DF) spectra of the C_3Ne, C_3Ar, C_3Kr, and C_3Xe complexes near the 0 2^- 0- 000, 0 4^- 0- 000, 0 2^+ 0- 000 and 100-000 bands of the {A}- {X} system of C_3 have been revisited. Some of the DF spectra of the Ne and Ar complexes have been recently obtained with a slightly improved resolution of 6-10 wn. All the DF spectra have been reassigned as emission from van der Waals (vdW) complexes and C_3 fragments. The optically excited C_3-Rg (Rg = rare-gas atom) complexes fluorescence and/or decay down to slightly lower (about 2-30 wn) vibrational levels without changing the internal energy of C_3 and then predissociate via the continua of the nearby vibronic states of C_3. The available dissociation channels depend on the binding energy of the ground electronic state complex. Exceptions have been found at the vdW bands near the 0 4^- 0- 000 band of C_3. The binding energies of the ground electronic states of these four complexes will be discussed. G. Zhang, B.-G. Lin, S.-M. Wen, and Y.-C. Hsu, J. Chem. Phys. 20, 3189(2004) J.-M. Chao, K. S. Tham, G. Zhang, A. J. Merer, Y.-C. Hsu, and W.-P. Hu, J. Chem. Phys. 34, 074313(2011)

  4. Revisiting post-infectious glomerulonephritis in the emerging era of C3 glomerulopathy

    PubMed Central

    Khalighi, Mazdak A.; Wang, Shihtien; Henriksen, Kammi J.; Bock, Margret; Keswani, Mahima; Meehan, Shane M.; Chang, Anthony

    2016-01-01

    Background Post-infectious glomerulonephritis (PIGN) is an immune complex-mediated glomerular injury that typically resolves. Dominant C3 deposition is characteristic of PIGN, but with the emergence of C3 glomerulonephritis (C3GN) as a distinct entity, it is unclear how the pathologic similarities between PIGN and C3GN should be reconciled. Therefore, nephrologists and nephropathologists need additional guidance at the time of biopsy. Methods We studied 23 pediatric and young adult patients diagnosed with PIGN. Patients were divided into two groups, one with co-dominance between C3 and immunoglobulins and the other meeting proposed diagnostic criteria for C3GN. Clinical and pathological features were compared. Results No clinical and/or pathological features could distinguish between those with C3-co-dominant deposits and those with C3 dominance. Nearly all patients in both groups regained their baseline renal function without clinical intervention. Conclusions Although the identification of abnormalities of the alternative pathway of complement is characteristic of C3GN, testing is not widely available and the turnaround time often exceeds 1 month. Our study found that PIGN with either co-dominant or dominant C3 deposition in a cohort of young patients has excellent short-term outcomes. Close clinical observation for persistent abnormalities, such as hypocomplementemia, prolonged hematuria or proteinuria, is recommended to single out patients that may harbor intrinsic complement abnormalities. PMID:27274823

  5. Two-Dimensional Nb-Based M 4 C 3 Solid Solutions (MXenes)

    DOE PAGES

    Yang, Jian; Naguib, Michael; Ghidiu, Michael; Pan, Li-Mei; Gu, Jian; Nanda, Jagjit; Halim, Joseph; Gogotsi, Yury; Barsoum, Michel W.; Zhou, Y.

    2015-10-15

    Two new two-dimensional Nb4C3-based solid solutions (MXenes), (Nb0.8,Ti0.2)4C3Tx and (Nb0.8,Zr0.2)4C3Tx (where T is a surface termination) were synthesizedas confirmed by X-ray diffractionfrom their corresponding MAX phase precursors (Nb0.8,Ti0.2)4AlC3 and (Nb0.8,Zr0.2)4AlC3. In our report we discuss Zr-containing MXene. We also studied intercalation of Li ions into these two compositions, and Nb4C3Tx in order to determine the potential of those materials for energy storage applications. Lithiation and delithiation peaks at 2.26 and 2.35 V, respectively, appeared in the case of Nb4C3Tx, but were not present in Nb2CTx. After 20 cycles at a rate of C/4, the specific capacities of (Nb0.8,Ti0.2)4C3Txand (Nb0.8,Ti0.2)4C3Tx weremore » 158 and 132 mAh/g, respectively, both slightly lower than the capacity of Nb4C3Tx.« less

  6. Factor C acts as a lipopolysaccharide-responsive C3 convertase in horseshoe crab complement activation.

    PubMed

    Ariki, Shigeru; Takahara, Shusaku; Shibata, Toshio; Fukuoka, Takaaki; Ozaki, Aya; Endo, Yuichi; Fujita, Teizo; Koshiba, Takumi; Kawabata, Shun-ichiro

    2008-12-01

    The complement system in vertebrates plays an important role in host defense against and clearance of invading microbes, in which complement component C3 plays an essential role in the opsonization of pathogens, whereas the molecular mechanism underlying C3 activation in invertebrates remains unknown. In an effort to understand the molecular activation mechanism of invertebrate C3, we isolated and characterized an ortholog of C3 (designated TtC3) from the horseshoe crab Tachypleus tridentatus. Flow cytometric analysis using an Ab against TtC3 revealed that the horseshoe crab complement system opsonizes both Gram-negative and Gram-positive bacteria. Evaluation of the ability of various pathogen-associated molecular patterns to promote the proteolytic conversion of TtC3 to TtC3b in hemocyanin-depleted plasma indicated that LPS, but not zymosan, peptidoglycan, or laminarin, strongly induces this conversion, highlighting the selective response of the complement system to LPS stimulation. Although originally characterized as an LPS-sensitive initiator of hemolymph coagulation stored within hemocytes, we identified factor C in hemolymph plasma. An anti-factor C Ab inhibited various LPS-induced phenomena, including plasma amidase activity, the proteolytic activation of TtC3, and the deposition of TtC3b on the surface of Gram-negative bacteria. Moreover, activated factor C present on the surface of Gram-negative bacteria directly catalyzed the proteolytic conversion of the purified TtC3, thereby promoting TtC3b deposition. We conclude that factor C acts as an LPS-responsive C3 convertase on the surface of invading Gram-negative bacteria in the initial phase of horseshoe crab complement activation.

  7. Demonstration of a specific C3a receptor on guinea pig platelets

    SciTech Connect

    Fukuoka, Y.; Hugli, T.E.

    1988-05-15

    Guinea pig platelets reportedly contain receptors specific for the anaphylatoxin C3a based on both ligand-binding studies and functional responses. A portion of the human 125I-C3a that binds to guinea pig platelets is competitively displaced by excess unlabeled C3a; however, the majority of ligand uptake was nonspecific. Uptake of 125I-C3a by guinea pig platelets is maximal in 1 min, and stimulation of guinea pig platelets by thrombin, ADP, or the Ca2+ ionophore A23187 showed little influence on binding of the ligand. Scatchard analysis indicated that approximately 1200 binding sites for C3a exist per cell with an estimated Kd of 8 x 10(-10) M. Human C3a des Arg also binds to guinea pig platelets, but Scatchard analysis indicated that no specific binding occurred. Because the ligand-binding studies were complicated by high levels of nonspecific uptake, we attempted to chemically cross-link the C3a molecule to a specific component on the platelet surface. Cross-linkage of 125I-C3a to guinea pig platelets with bis(sulfosuccinimidyl)suberate revealed radioactive complexes at 105,000 and 115,000 m.w. on SDS-PAGE gels by autoradiographic analysis. In the presence of excess unlabeled C3a, complex formation was inhibited. No cross-linkage could be demonstrated between the inactive 125I-C3a des Arg and the putative C3a-R on guinea pig platelets. Human C3a, but not C3a des Arg induces serotonin release and aggregation of the guinea pig platelets. Human C3a was unable to induce either serotonin release or promote aggregation of human platelets. Uptake of human 125I-C3a by human platelets was not saturable, and Scatchard analysis was inconclusive. Attempts to cross-link 125I-C3a to components on the surface of human platelets also failed to reveal a ligand-receptor complex. Therefore, we conclude that guinea pig platelets have specific surface receptors to C3a and that human platelets appear devoid of receptors to the anaphylatoxin.

  8. Enhanced Attitude Control Experiment for SSTI Lewis Spacecraft

    NASA Technical Reports Server (NTRS)

    Maghami, Peoman G.

    1997-01-01

    The enhanced attitude control system experiment is a technology demonstration experiment on the NASA's small spacecraft technology initiative program's Lewis spacecraft to evaluate advanced attitude control strategies. The purpose of the enhanced attitude control system experiment is to evaluate the feasibility of designing and implementing robust multi-input/multi-output attitude control strategies for enhanced pointing performance of spacecraft to improve the quality of the measurements of the science instruments. Different control design strategies based on modern and robust control theories are being considered for the enhanced attitude control system experiment. This paper describes the experiment as well as the design and synthesis of a mixed H(sub 2)/H(sub infinity) controller for attitude control. The control synthesis uses a nonlinear programming technique to tune the controller parameters and impose robustness and performance constraints. Simulations are carried out to demonstrate the feasibility of the proposed attitude control design strategy. Introduction

  9. Enhanced Photocatalytic Performance of Luminescent g-C3N4 Photocatalyst in Darkroom

    NASA Astrophysics Data System (ADS)

    Li, Huihui; Yin, Shu; Sato, Tsugio; Wang, Yuhua

    2016-02-01

    Graphitic-C3N4(g-C3N4), a low-cost visible-light-driven photocatalyst, was used for the photocatalytic oxidation of aqueous methylene blue (MB) in the dark with Sr4Al14O25:(Eu,Dy) assistance. The Sr4Al14O25:(Eu,Dy)/g-C3N4 photocatalysts were fabricated through the ultrasonic dispersion method. The commercial Sr4Al14O25:(Eu,Dy) phosphor was used as a long afterglow supplier for exciting g-C3N4 in the dark. The results demonstrated that the metal-free g-C3N4 photocatalyst could use the eye-visible long afterglow to photocatalytically decompose MB dyes in the dark. This work may expand the appealing application of g-C3N4 for the environmental cleanup.

  10. 17 CFR 240.15c3-1 - Net capital requirements for brokers or dealers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... the computation required by § 240.15c3-3(e) and set forth in Exhibit A, § 240.15c3-3a, on a weekly... Examining Authorities pursuant to 17 CFR 240.17a-11, if the market maker or specialist fails to deposit any... borrowed from customers in accordance with the provisions of 17 CFR 240.15c3-3 and margin...

  11. 17 CFR 240.15c3-1 - Net capital requirements for brokers or dealers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... the computation required by § 240.15c3-3(e) and set forth in Exhibit A, § 240.15c3-3a, on a weekly... Examining Authorities pursuant to 17 CFR 240.17a-11, if the market maker or specialist fails to deposit any... borrowed from customers in accordance with the provisions of 17 CFR 240.15c3-3 and margin...

  12. 17 CFR 240.15c3-1 - Net capital requirements for brokers or dealers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... the computation required by § 240.15c3-3(e) and set forth in Exhibit A, § 240.15c3-3a, on a weekly... Examining Authorities pursuant to 17 CFR 240.17a-11, if the market maker or specialist fails to deposit any... borrowed from customers in accordance with the provisions of 17 CFR 240.15c3-3 and margin...

  13. Functional Characterization of Autoantibodies against Complement Component C3 in Patients with Lupus Nephritis*

    PubMed Central

    Vasilev, Vasil V.; Noe, Remi; Dragon-Durey, Marie-Agnes; Chauvet, Sophie; Lazarov, Valentin J.; Deliyska, Boriana P.; Fremeaux-Bacchi, Veronique; Dimitrov, Jordan D.; Roumenina, Lubka T.

    2015-01-01

    Lupus nephritis (LN) is a complication of the autoimmune disease systemic lupus erythematosus. Because the complement system plays a critical role in orchestrating inflammatory and immune responses as well as in the clearance of immune complexes, autoreactivity to complement components may have considerable pathological consequences. Autoantibodies against the central complement component C3 have been reported in systemic lupus erythematosus, but their molecular mechanism and functional relevance are not well understood. The objective of this study was to evaluate the frequency and the functional properties of the anti-C3 autoantibodies. Anti-C3 autoantibodies were measured in plasma of 39 LN patients, and identification of their epitopes on the C3 molecule was performed. By using surface plasmon resonance, we analyzed the influence of patient-derived IgG antibodies on the interaction of C3b with Factor B, Factor H, and complement receptor 1. The capacity of these antibodies to dysregulate the C3 convertase on the surface of endothelial cell was measured by flow cytometry. Here we report that the frequency of anti-C3 autoantibodies in LN is ∼30%. They inhibited interactions of the negative complement regulators Factor H and complement receptor 1 with C3b. An enhanced C3 deposition was also observed on human endothelial cells in the presence of C3 autoantibodies. In addition, anti-C3 autoantibody levels correlated with disease activity. In conclusion, the anti-C3 autoantibodies in LN may contribute to the autoimmune pathology by their capacity to overactivate the complement system. PMID:26245903

  14. Lymphoblastoid cell supernatants increase expression of C3b receptors on human polymorphonuclear leucocytes: direct binding studies with 125I-C3b.

    PubMed Central

    Berger, M; Cross, A S

    1984-01-01

    Human PMN incubated in culture supernatants of the Raji long-term human lymphoblastoid cell line showed increased rosette formation with sheep erythrocytes coated with C3b (EIgM C4b3b) but no change in rosette formation with IgG-coated erythrocytes. This suggested a specific increase in cell surface C3b receptors, which was further investigated using 125I-C3b for direct binding studies. The results confirmed that specific binding of 125I-C3b to PMN incubated in culture supernatants increased up to three- to four-fold over binding to PMN incubated in control media alone. Scatchard analysis revealed that the apparent Ka for supernatant-treated cells, 3.36 +/- 0.89 X 10(7) L/M did not differ from the Ka for cells incubated in control media, 3.76 +/- 0.75 X 10(7) L/M, suggesting an increase in a single class of C3b receptors. Kinetic studies revealed that the active factor was present within 24 hr of culture of the Raji cells, and that neutrophils incubated in culture supernatants increased their C3b receptors continuously for up to 4 hr, the longest interval tested. The effect of the culture supernatant was lost with dilution beyond eight- to 10-fold. The results suggest that culture supernatants of this long-term lymphoblastoid cell line contain soluble factors that induce increased expression of C3b receptors on PMN and may thus serve as a model for study of important physiologic effects of lymphocyte products on PMN in vivo. PMID:6230308

  15. Compstatin analog Cp40 inhibits complement dysregulation in vitro in C3 glomerulopathy

    PubMed Central

    Zhang, Yuzhou; Shao, Dingwu; Ricklin, Daniel; Hilkin, Brieanna M.; Nester, Carla M.; Lambris, John D.; Smith, Richard J. H.

    2015-01-01

    C3 glomerulopathy (C3G) defines a group of untreatable ultra-rare renal diseases caused by uncontrolled activation of the alternative complement pathway. Nearly half of patients progress to end stage renal failure within 10 years. Cp40, a second-generation compstatin analog in clinical development, is a 14 amino-acid cyclic peptide that selectively inhibits complement activation in humans and non-human primates by binding to C3 and C3b. We hypothesized that by targeting C3 Cp40 would provide an effective treatment for C3G. By investigating its effects in vitro using multiple assays of complement activity, we show that Cp40 prevents complement-mediated lysis of sheep erythrocytes in sera from C3G patients, prevents complement dysregulation in the presence of patient-derived autoantibodies to the C3 and C5 convertases, and prevents complement dysregulation associated with disease-causing genetic mutations. In aggregate, these data suggest that Cp40 may offer a novel and promising therapeutic option to C3G patients as a disease-specific, targeted therapy. As such, Cp40 could represent a major advance in the treatment of this disease. PMID:25982307

  16. Growth characteristics of primary M7C3 carbide in hypereutectic Fe-Cr-C alloy.

    PubMed

    Liu, Sha; Zhou, Yefei; Xing, Xiaolei; Wang, Jibo; Ren, Xuejun; Yang, Qingxiang

    2016-01-01

    The microstructure of the hypereutectic Fe-Cr-C alloy is observed by optical microscopy (OM). The initial growth morphology, the crystallographic structure, the semi-molten morphology and the stacking faults of the primary M7C3 carbide are observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The in-suit growth process of the primary M7C3 carbide was observed by confocal laser microscope (CLM). It is found that the primary M7C3 carbide in hypereutectic Fe-Cr-C alloy is irregular polygonal shape with several hollows in the center and gaps on the edge. Some primary M7C3 carbides are formed by layers of shell or/and consist of multiple parts. In the initial growth period, the primary M7C3 carbide forms protrusion parallel to {} crystal planes. The extending and revolving protrusion forms the carbide shell. The electron backscattered diffraction (EBSD) maps show that the primary M7C3 carbide consists of multiple parts. The semi-molten M7C3 carbide contains unmelted shell and several small-scale carbides inside, which further proves that the primary M7C3 carbide is not an overall block. It is believed that the coalescence of the primary M7C3 carbides is ascribed to the growing condition of the protrusion and the gap filling process. PMID:27596718

  17. Growth characteristics of primary M7C3 carbide in hypereutectic Fe-Cr-C alloy.

    PubMed

    Liu, Sha; Zhou, Yefei; Xing, Xiaolei; Wang, Jibo; Ren, Xuejun; Yang, Qingxiang

    2016-09-06

    The microstructure of the hypereutectic Fe-Cr-C alloy is observed by optical microscopy (OM). The initial growth morphology, the crystallographic structure, the semi-molten morphology and the stacking faults of the primary M7C3 carbide are observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The in-suit growth process of the primary M7C3 carbide was observed by confocal laser microscope (CLM). It is found that the primary M7C3 carbide in hypereutectic Fe-Cr-C alloy is irregular polygonal shape with several hollows in the center and gaps on the edge. Some primary M7C3 carbides are formed by layers of shell or/and consist of multiple parts. In the initial growth period, the primary M7C3 carbide forms protrusion parallel to {} crystal planes. The extending and revolving protrusion forms the carbide shell. The electron backscattered diffraction (EBSD) maps show that the primary M7C3 carbide consists of multiple parts. The semi-molten M7C3 carbide contains unmelted shell and several small-scale carbides inside, which further proves that the primary M7C3 carbide is not an overall block. It is believed that the coalescence of the primary M7C3 carbides is ascribed to the growing condition of the protrusion and the gap filling process.

  18. Functional analysis of Cobra Venom Factor/human C3 chimeras transiently expressed in mammalian cells.

    PubMed

    Kölln, Johanna; Matzas, Mark; Jänner, Nathalie; Mix, Thorsten; Klensang, Katrin; Bredehorst, Reinhard; Spillner, Edzard

    2004-05-01

    The complement activating venom component Cobra Venom Factor (CVF), a functional and structural homologue of the human complement component C3, forms a stable CVF-dependent C3 convertase complex, which, in contrast to C3-dependent convertase effects continuous activation of the complement and, thereby, decomplementation. In order to elucidate the mechanism underlying the enhanced activity of CVF compared to human C3, we generated two CVF/C3 chimeras and established different affinity-based assay systems for functional analysis of these constructs. To allow for convenient expression and subsequent functional characterisation, the CVF/C3 chimeras as well as CVF and C3 were transiently expressed in mammalian cells. Problems due to the low concentration of the recombinant proteins in the supernatants of transient expressions were circumvented by fusion to peptide tags enabling their efficient immobilisation onto suitable surfaces and subsequent characterisation. In an alternative approach monoclonal antibody fragments generated from a semisynthetic phage display scFv library were employed for concentrating the recombinant proteins by immunoprecipitation. Utilising both approaches all transiently expressed proteins could be characterised for their complement consumption activity. The data obtained with the CVF/C3 chimeras demonstrate that the increased stability of the CVFBb complex is independent of the domains in CVF corresponding to binding sites of factor B and H and the cleavage sites of factor I in the human C3 molecule. PMID:15140572

  19. Regulation by retinoic acid of acylation-stimulating protein and complement C3 in human adipocytes.

    PubMed Central

    Scantlebury, T; Sniderman, A D; Cianflone, K

    2001-01-01

    Acylation-stimulating protein (ASP), a product of complement C3, stimulates triacylglycerol synthesis in adipocytes. Previous studies have identified transthyretin, associated with chylomicrons, as a stimulator of C3 and ASP production. Since both transthyretin and chylomicrons transport retinyl ester/retinol, our goal was to investigate whether retinoic acid (RA) could be a potential hormonal mediator of the effect. Inhibitors of protein synthesis and protein secretion eliminated the stimulatory effects of chylomicrons on both C3 and ASP production in human differentiated adipocytes, suggesting that de novo protein synthesis and secretion are both required. Incubation with chylomicrons increased C3 mRNA levels (37+/-1.5%). RA alone or with chylomicrons had a stimulatory effect on C3 production (29-fold at 16.6 nM RA) and ASP production. An RA receptor antagonist blocked stimulation of C3 mRNA and C3 secretion by both RA and chylomicrons. Finally, RA and chylomicrons activated a 1.8 kb C3-promoter-luciferase construct transfected into 3T3-F442 and 3T3-L1 cells (by 41+/-0.2% and 69+/-0.3% respectively), possibly via RA receptor half-sites identified by sequence analysis. This is the first evidence documenting stimulation by RA of the C3 gene. Thus we propose RA as a novel cellular trigger in chylomicrons that subsequently results in increased ASP production by adipocytes after a meal. PMID:11368771

  20. Temperature variable ion trap studies of C3Hn+ with H2 and HD.

    PubMed

    Savić, I; Gerlich, D

    2005-03-01

    Hydrogenation and deuteration of C3+, C3H+, C3H2+ in collisions with H2 and HD has been studied from room temperature down to 10 K using a 22-pole ion trap. Although exothermic, hydrogenation of C3+ is rather slow at room temperature but becomes faster with decreasing temperature. In addition to the increasing lifetime of the collision complex this behavior may be caused by the floppy structure of C3+ and the freezing of soft bending modes below 50 K. For C3(+) + HD it has been shown that production of C3D+ is slightly favored over C3H+ formation. The controversy over which products are really formed in C3H(+) + H2 collisions and deuterated variants has a long history. Previous and new ion trap results prove that formation of C3H2(+) + H is not endothermic but rather fast, in contradiction to erroneous conclusions from flow tube experiments and ab initio calculations. In addition the reaction shows a complicated isotope dependence, most probably caused by the influence of zero point energies in entrance and exit transition states. For example hydrogen abstraction with HD is faster than with H2 while radiative association is slower. The most surprising result has been obtained for C3H(+) + HD. Here C3HD+ formation is over one hundred times faster than C3H2+. In addition to the details of the potential energy surface it may be that in this case an H-HD exchange reaction takes place via an open-chain propargyl cation intermediate (H2CCCH+). Reactions of C3H2+ and C3H3+ with H2 are very slow but, due to the unique sensitivity of the trapping technique, significant rate coefficients have been determined. The presented results are of fundamental importance for understanding the energetics, structures and reaction dynamics of the deuterated variant of the C3Hn+ collision system. They indicate that the previous quantum chemical calculations are not accurate enough for understanding the low energy behavior of the Cn,Hm+ reaction systems. The laboratory experiments are of

  1. Growth characteristics of primary M7C3 carbide in hypereutectic Fe-Cr-C alloy

    NASA Astrophysics Data System (ADS)

    Liu, Sha; Zhou, Yefei; Xing, Xiaolei; Wang, Jibo; Ren, Xuejun; Yang, Qingxiang

    2016-09-01

    The microstructure of the hypereutectic Fe-Cr-C alloy is observed by optical microscopy (OM). The initial growth morphology, the crystallographic structure, the semi-molten morphology and the stacking faults of the primary M7C3 carbide are observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The in-suit growth process of the primary M7C3 carbide was observed by confocal laser microscope (CLM). It is found that the primary M7C3 carbide in hypereutectic Fe-Cr-C alloy is irregular polygonal shape with several hollows in the center and gaps on the edge. Some primary M7C3 carbides are formed by layers of shell or/and consist of multiple parts. In the initial growth period, the primary M7C3 carbide forms protrusion parallel to {} crystal planes. The extending and revolving protrusion forms the carbide shell. The electron backscattered diffraction (EBSD) maps show that the primary M7C3 carbide consists of multiple parts. The semi-molten M7C3 carbide contains unmelted shell and several small-scale carbides inside, which further proves that the primary M7C3 carbide is not an overall block. It is believed that the coalescence of the primary M7C3 carbides is ascribed to the growing condition of the protrusion and the gap filling process.

  2. Potent complement C3a receptor agonists derived from oxazole amino acids: Structure-activity relationships.

    PubMed

    Singh, Ranee; Reed, Anthony N; Chu, Peifei; Scully, Conor C G; Yau, Mei-Kwan; Suen, Jacky Y; Durek, Thomas; Reid, Robert C; Fairlie, David P

    2015-12-01

    Potent ligands for the human complement C3a receptor (C3aR) were developed from the almost inactive tripeptide Leu-Ala-Arg corresponding to the three C-terminal residues of the endogenous peptide agonist C3a. The analogous Leu-Ser-Arg was modified by condensing the serine side chain with the leucine carbonyl with elimination of water to form leucine-oxazole-arginine. Subsequent elaboration with a variety of N-terminal amide capping groups produced agonists as potent as human C3a itself in stimulating Ca(2+) release from human macrophages. Structure-activity relationships are discussed.

  3. Proteome Alterations of Hippocampal Cells Caused by Clostridium botulinum C3 Exoenzyme.

    PubMed

    Schröder, Anke; Rohrbeck, Astrid; Just, Ingo; Pich, Andreas

    2015-11-01

    C3bot from Clostridium botulinum is a bacterial mono-ADP-ribosylating enzyme, which transfers an ADP-ribose moiety onto the small GTPases Rho A/B/C. C3bot and the catalytic inactive mutant (C3E174Q) cause axonal and dendritic growth as well as branching in primary hippocampal neurons. In cultured murine hippocampal HT22 cells, protein abundances were analyzed in response to C3bot or C3E174Q treatment using a shotgun proteomics approach. Proteome analyses were performed at four time points over 6 days. More than 4000 protein groups were identified at each time point and quantified in triplicate analyses. On day one, 46 proteins showed an altered abundance, and after 6 days, more than 700 proteins responded to C3bot with an up- or down-regulation. In contrast, C3E174Q had no provable impact on protein abundance. Protein quantification was verified for several proteins by multiple reaction monitoring. Data analysis of altered proteins revealed different cellular processes that were affected by C3bot. They are particularly involved in mitochondrial and lysosomal processes, adhesion, carbohydrate and glucose metabolism, signal transduction, and nuclear proteins of translation and ribosome biogenesis. The results of this study gain novel insights into the function of C3bot in hippocampal cells. PMID:26393427

  4. Halogenation and proteolysis of complement component C3 on Salmonella typhimurium during phagocytosis by human neutrophils

    SciTech Connect

    Joiner, K.A.; Schweinle, J.E.

    1989-05-01

    We examined the fate of C component C3 on the surface of Salmonella typhimurium during ingestion by human neutrophils. Initial experiments showed that C3 fragments and C3-acceptor complexes were the major serum ligands which were surface iodinated by canine myeloperoxidase on serum-incubated rough and smooth isolates of S. typhimurium. In contrast, labeled C3 was not identified when the same organisms were ingested by neutrophils in the presence of 125I-Na, a situation previously shown to iodinate particulate targets via the neutrophil myeloperoxidase-halide-H2O2 system. Pretreatment of neutrophils before phagocytosis with the lipid-soluble protease inhibitor diisopropylfluorophosphate (DFP), but not with other protease inhibitors (p-nitrophenylguanidinobenzoate, leupeptin, pepstatin), substantially blocked proteolysis of 125I-C3 on S. typhimurium strain RG108 during ingestion by neutrophils. Purification of neutrophil phagosomes containing S. typhimurium-bearing 125I-C3 showed that DFP but no other protease inhibitors blocked proteolysis of 125I-C3 within phagosomes. Iodinated C3-acceptor complexes were identified by immunoprecipitation from the detergent-insoluble fraction of phagosomes prepared from DFP-treated cells ingesting S. typhimurium in the presence of 125I-Na. These results show that C3 fragments on the surface of S. typhimurium are the major serum ligands which are halogenated and degraded by proteolysis during phagocytosis by human neutrophils, and suggest that the majority of proteolysis on the ingested target occurs within the neutrophil phagosome.

  5. Mutations in complement C3 predispose to development of atypical hemolytic uremic syndrome

    PubMed Central

    Miller, Elizabeth C.; Liszewski, M. Kathryn; Strain, Lisa; Blouin, Jacques; Brown, Alison L.; Moghal, Nadeem; Kaplan, Bernard S.; Weiss, Robert A.; Lhotta, Karl; Kapur, Gaurav; Mattoo, Tej; Nivet, Hubert; Wong, William; Gie, Sophie; de Ligny, Bruno Hurault; Fischbach, Michel; Gupta, Ritu; Hauhart, Richard; Meunier, Vincent; Loirat, Chantal; Dragon-Durey, Marie-Agnès; Fridman, Wolf H.; Janssen, Bert J. C.

    2008-01-01

    Atypical hemolytic uremic syndrome (aHUS) is a disease of complement dysregulation. In approximately 50% of patients, mutations have been described in the genes encoding the complement regulators factor H, MCP, and factor I or the activator factor B. We report here mutations in the central component of the complement cascade, C3, in association with aHUS. We describe 9 novel C3 mutations in 14 aHUS patients with a persistently low serum C3 level. We have demonstrated that 5 of these mutations are gain-of-function and 2 are inactivating. This establishes C3 as a susceptibility factor for aHUS. PMID:18796626

  6. Growth characteristics of primary M7C3 carbide in hypereutectic Fe-Cr-C alloy

    PubMed Central

    Liu, Sha; Zhou, Yefei; Xing, Xiaolei; Wang, Jibo; Ren, Xuejun; Yang, Qingxiang

    2016-01-01

    The microstructure of the hypereutectic Fe-Cr-C alloy is observed by optical microscopy (OM). The initial growth morphology, the crystallographic structure, the semi-molten morphology and the stacking faults of the primary M7C3 carbide are observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The in-suit growth process of the primary M7C3 carbide was observed by confocal laser microscope (CLM). It is found that the primary M7C3 carbide in hypereutectic Fe-Cr-C alloy is irregular polygonal shape with several hollows in the center and gaps on the edge. Some primary M7C3 carbides are formed by layers of shell or/and consist of multiple parts. In the initial growth period, the primary M7C3 carbide forms protrusion parallel to {} crystal planes. The extending and revolving protrusion forms the carbide shell. The electron backscattered diffraction (EBSD) maps show that the primary M7C3 carbide consists of multiple parts. The semi-molten M7C3 carbide contains unmelted shell and several small-scale carbides inside, which further proves that the primary M7C3 carbide is not an overall block. It is believed that the coalescence of the primary M7C3 carbides is ascribed to the growing condition of the protrusion and the gap filling process. PMID:27596718

  7. Evolution of the complement system C3 gene in Antarctic teleosts.

    PubMed

    Melillo, Daniela; Varriale, Sonia; Giacomelli, Stefano; Natale, Lenina; Bargelloni, Luca; Oreste, Umberto; Pinto, Maria Rosaria; Coscia, Maria Rosaria

    2015-08-01

    Notothenioidei are typical Antarctic teleosts evolved to adapt to the very low temperatures of the Antarctic seas. Aim of the present paper is to investigate sequence and structure of C3, the third component of the complement system of the notothenioid Trematomus bernacchii and Chionodraco hamatus. We determined the complete nucleotide sequence of two C3 isoforms of T. bernacchii and a single C3 isoform of C. hamatus. These sequences were aligned against other homologous teleost sequences to check for the presence of diversifying selection. Evidence for positive selection was observed in the evolutionary lineage of Antarctic teleost C3 sequences, especially in that of C. hamatus, the most recently diverged species. Adaptive selection affected numerous amino acid positions including three residues located in the anaphylatoxin domain. In an attempt to evaluate the link between sequence variants and specific structural features, we constructed molecular models of Antarctic teleost C3s, of their proteolytic fragments C3b and C3a, and of the corresponding molecules of the phylogenetically related temperate species Epinephelus coioides, using human crystallographic structures as templates. Subsequently, we compared dynamic features of these models by molecular dynamics simulations and found that the Antarctic C3s models show higher flexibility, which likely allows for more pronounced movements of both the TED domain in C3b and the carboxyl-terminal region of C3a. As such dynamic features are associated to positively selected sites, it appears that Antarctic teleost C3 molecules positively evolved toward an increased flexibility, to cope with low kinetic energy levels of the Antarctic marine environment.

  8. 17 CFR 240.15c3-2 - Customers' free credit balances.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... balances. 240.15c3-2 Section 240.15c3-2 Commodity and Securities Exchanges SECURITIES AND EXCHANGE... Customers' free credit balances. No broker or dealer shall use any funds arising out of any free credit balance carried for the account of any customer in connection with the operation of the business of...

  9. 17 CFR 240.15c3-2 - Customers' free credit balances.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... balances. 240.15c3-2 Section 240.15c3-2 Commodity and Securities Exchanges SECURITIES AND EXCHANGE... Customers' free credit balances. No broker or dealer shall use any funds arising out of any free credit balance carried for the account of any customer in connection with the operation of the business of...

  10. 17 CFR 240.15c3-2 - Customers' free credit balances.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... balances. 240.15c3-2 Section 240.15c3-2 Commodity and Securities Exchanges SECURITIES AND EXCHANGE... Customers' free credit balances. No broker or dealer shall use any funds arising out of any free credit balance carried for the account of any customer in connection with the operation of the business of...

  11. 17 CFR 240.15c3-2 - Customers' free credit balances.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... balances. 240.15c3-2 Section 240.15c3-2 Commodity and Securities Exchanges SECURITIES AND EXCHANGE... Customers' free credit balances. No broker or dealer shall use any funds arising out of any free credit balance carried for the account of any customer in connection with the operation of the business of...

  12. Electronic and rovibrational quantum chemical analysis of C3P-: the next interstellar anion?

    NASA Astrophysics Data System (ADS)

    Fortenberry, Ryan C.; Lukemire, Joseph A.

    2015-11-01

    C3P- is analogous to the known interstellar anion C3N- with phosphorus replacing nitrogen in a simple step down the periodic table. In this work, it is shown that C3P- is likely to possess a dipole-bound excited state. It has been hypothesized and observationally supported that dipole-bound excited states are an avenue through which anions could be formed in the interstellar medium. Additionally, C3P- has a valence excited state that may lead to further stabilization of this molecule, and C3P- has a larger dipole moment than neutral C3P (˜6 D versus ˜4 D). As such, C3P- is probably a more detectable astromolecule than even its corresponding neutral radical. Highly accurate quantum chemical quartic force fields are also applied to C3P- and its singly 13C substituted isotopologues in order to provide structures, vibrational frequencies, and spectroscopic constants that may aid in its detection.

  13. Isoelectric point and adsorption activity of porous g-C3N4

    NASA Astrophysics Data System (ADS)

    Zhu, Bicheng; Xia, Pengfei; Ho, Wingkei; Yu, Jiaguo

    2015-07-01

    The isoelectric point (IEP) is an important physicochemical parameter of many compounds, such as oxides, hydroxides, and nitrides, and can contribute to estimation of the surface charges of compound particles at various pH conditions. In this work, three types of graphitic carbon nitrides (g-C3N4) were synthesized by directly heating melamine, thiourea, and urea. The prepared samples showed different microstructures and IEPs that influenced their adsorption activity. Differences in microstructure resulted from the various precursors used during synthesis. The IEPs of the obtained g-C3N4 were measured to be approximately 4-5, which is due to the equilibrium of chemical reactions between hydrogen ions, hydroxyl ions, and amine groups on the g-C3N4 surface. The IEP of g-C3N4 prepared from thiourea was lower than those of the corresponding samples prepared from melamine and urea. The adsorption activity of methylene blue on g-C3N4 prepared from urea and thiourea was excellent, which indicates that g-C3N4 is a promising adsorbent. This work provides a useful reference for choosing precursors with which to prepare g-C3N4 and combining g-C3N4 with other compounds in solution.

  14. High-yield synthesis and optical properties of g-C3N4.

    PubMed

    Yuan, Yanwen; Zhang, Lulu; Xing, Jun; Utama, M Iqbal Bakti; Lu, Xin; Du, Kezhao; Li, Yongmei; Hu, Xiao; Wang, Shijie; Genç, Aziz; Dunin-Borkowski, Rafal; Arbiol, Jordi; Xiong, Qihua

    2015-08-01

    Graphitic carbon nitride (g-C3N4), a metal-free semiconductor with a band gap of 2.7 eV, has received considerable attention owing to its fascinating photocatalytic performances under visible-light. g-C3N4 exhibits high thermal and chemical stability and non-toxicity such that it has been considered as the most promising photocatalyst for environmental improvement and energy conservation. Hence, it is of great importance to obtain high-quality g-C3N4 and gain a clear understanding of its optical properties. Herein, we report a high-yield synthesis of g-C3N4 products via heating of high vacuum-sealed melamine powder in an ampoule at temperatures between 450 and 650 °C. Using transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), electron energy loss spectroscopy (EELS), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), the chemical composition and crystallization of the as-produced g-C3N4 are demonstrated. A systematic optical study of g-C3N4 is carried out with several approaches. The optical phonon behavior of g-C3N4 is revealed by infrared and Raman spectroscopy, and the emission properties of g-C3N4 are investigated using photoluminescence (PL) spectroscopy, while the photocatalytic properties are explored by the photodegradation experiment. PMID:26152840

  15. Evolutionary implications of C3 -C4 intermediates in the grass Alloteropsis semialata.

    PubMed

    Lundgren, Marjorie R; Christin, Pascal-Antoine; Escobar, Emmanuel Gonzalez; Ripley, Brad S; Besnard, Guillaume; Long, Christine M; Hattersley, Paul W; Ellis, Roger P; Leegood, Richard C; Osborne, Colin P

    2016-09-01

    C4 photosynthesis is a complex trait resulting from a series of anatomical and biochemical modifications to the ancestral C3 pathway. It is thought to evolve in a stepwise manner, creating intermediates with different combinations of C4 -like components. Determining the adaptive value of these components is key to understanding how C4 photosynthesis can gradually assemble through natural selection. Here, we decompose the photosynthetic phenotypes of numerous individuals of the grass Alloteropsis semialata, the only species known to include both C3 and C4 genotypes. Analyses of δ(13) C, physiology and leaf anatomy demonstrate for the first time the existence of physiological C3 -C4 intermediate individuals in the species. Based on previous phylogenetic analyses, the C3 -C4 individuals are not hybrids between the C3 and C4 genotypes analysed, but instead belong to a distinct genetic lineage, and might have given rise to C4 descendants. C3 A. semialata, present in colder climates, likely represents a reversal from a C3 -C4 intermediate state, indicating that, unlike C4 photosynthesis, evolution of the C3 -C4 phenotype is not irreversible. PMID:26524631

  16. C3 glomerulopathy–associated CFHR1 mutation alters FHR oligomerization and complement regulation

    PubMed Central

    Tortajada, Agustín; Yébenes, Hugo; Abarrategui-Garrido, Cynthia; Anter, Jaouad; García-Fernández, Jesús M.; Martínez-Barricarte, Rubén; Alba-Domínguez, María; Malik, Talat H.; Bedoya, Rafael; Pérez, Rocío Cabrera; Trascasa, Margarita López; Pickering, Matthew C.; Harris, Claire L.; Sánchez-Corral, Pilar; Llorca, Oscar; Rodríguez de Córdoba, Santiago

    2013-01-01

    C3 glomerulopathies (C3G) are a group of severe renal diseases with distinct patterns of glomerular inflammation and C3 deposition caused by complement dysregulation. Here we report the identification of a familial C3G-associated genomic mutation in the gene complement factor H–related 1 (CFHR1), which encodes FHR1. The mutation resulted in the duplication of the N-terminal short consensus repeats (SCRs) that are conserved in FHR2 and FHR5. We determined that native FHR1, FHR2, and FHR5 circulate in plasma as homo- and hetero-oligomeric complexes, the formation of which is likely mediated by the conserved N-terminal domain. In mutant FHR1, duplication of the N-terminal domain resulted in the formation of unusually large multimeric FHR complexes that exhibited increased avidity for the FHR1 ligands C3b, iC3b, and C3dg and enhanced competition with complement factor H (FH) in surface plasmon resonance (SPR) studies and hemolytic assays. These data revealed that FHR1, FHR2, and FHR5 organize a combinatorial repertoire of oligomeric complexes and demonstrated that changes in FHR oligomerization influence the regulation of complement activation. In summary, our identification and characterization of a unique CFHR1 mutation provides insights into the biology of the FHRs and contributes to our understanding of the pathogenic mechanisms underlying C3G. PMID:23728178

  17. Final Hazard Categorization for the Remediation of the 116-C-3 Chemical Waste Tanks

    SciTech Connect

    T. M. Blakley; W. D. Schofield

    2007-09-10

    This final hazard categorization (FHC) document examines the hazards, identifies appropriate controls to manage the hazards, and documents the commitments for the 116-C-3 Chemical Waste Tanks Remediation Project. The remediation activities analyzed in this FHC are based on recommended treatment and disposal alternatives described in the Engineering Evaluation for the Remediation to the 116-C-3 Chemical Waste Tanks (BHI 2005e).

  18. Guiding Inquiry with Biography Breaks and the C3 Framework: Can One Person Make a Difference?

    ERIC Educational Resources Information Center

    Young, Terrell A.; Miner, Amy Baird

    2015-01-01

    The purpose of this article is to explore how teachers can use biography breaks to address the National Council of the Social Studies C3 inquiry framework and in the process meet requirements of the Common Core State Standards. We begin by illustrating and explaining biography breaks. Then we introduce the C3 framework and explain as well as…

  19. 26 CFR 301.6501(n)-2 - Certain contributions to section 501(c)(3) organizations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Certain contributions to section 501(c)(3) organizations. 301.6501(n)-2 Section 301.6501(n)-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE... Assessment and Collection § 301.6501(n)-2 Certain contributions to section 501(c)(3) organizations. If...

  20. 26 CFR 301.6501(n)-2 - Certain contributions to section 501(c)(3) organizations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 18 2011-04-01 2011-04-01 false Certain contributions to section 501(c)(3) organizations. 301.6501(n)-2 Section 301.6501(n)-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE... Assessment and Collection § 301.6501(n)-2 Certain contributions to section 501(c)(3) organizations. If...

  1. Evolutionary implications of C3 -C4 intermediates in the grass Alloteropsis semialata.

    PubMed

    Lundgren, Marjorie R; Christin, Pascal-Antoine; Escobar, Emmanuel Gonzalez; Ripley, Brad S; Besnard, Guillaume; Long, Christine M; Hattersley, Paul W; Ellis, Roger P; Leegood, Richard C; Osborne, Colin P

    2016-09-01

    C4 photosynthesis is a complex trait resulting from a series of anatomical and biochemical modifications to the ancestral C3 pathway. It is thought to evolve in a stepwise manner, creating intermediates with different combinations of C4 -like components. Determining the adaptive value of these components is key to understanding how C4 photosynthesis can gradually assemble through natural selection. Here, we decompose the photosynthetic phenotypes of numerous individuals of the grass Alloteropsis semialata, the only species known to include both C3 and C4 genotypes. Analyses of δ(13) C, physiology and leaf anatomy demonstrate for the first time the existence of physiological C3 -C4 intermediate individuals in the species. Based on previous phylogenetic analyses, the C3 -C4 individuals are not hybrids between the C3 and C4 genotypes analysed, but instead belong to a distinct genetic lineage, and might have given rise to C4 descendants. C3 A. semialata, present in colder climates, likely represents a reversal from a C3 -C4 intermediate state, indicating that, unlike C4 photosynthesis, evolution of the C3 -C4 phenotype is not irreversible.

  2. Mapping interactions between complement C3 and regulators using mutations in atypical hemolytic uremic syndrome

    PubMed Central

    Schramm, Elizabeth C.; Roumenina, Lubka T.; Rybkine, Tania; Chauvet, Sophie; Vieira-Martins, Paula; Hue, Christophe; Maga, Tara; Valoti, Elisabetta; Wilson, Valerie; Jokiranta, Sakari; Smith, Richard J. H.; Noris, Marina; Goodship, Tim; Atkinson, John P.

    2015-01-01

    The pathogenesis of atypical hemolytic uremic syndrome (aHUS) is strongly linked to dysregulation of the alternative pathway of the complement system. Mutations in complement genes have been identified in about two-thirds of cases, with 5% to 15% being in C3. In this study, 23 aHUS-associated genetic changes in C3 were characterized relative to their interaction with the control proteins factor H (FH), membrane cofactor protein (MCP; CD46), and complement receptor 1 (CR1; CD35). In surface plasmon resonance experiments, 17 mutant recombinant proteins demonstrated a defect in binding to FH and/or MCP, whereas 2 demonstrated reduced binding to CR1. In the majority of cases, decreased binding affinity translated to a decrease in proteolytic inactivation (known as cofactor activity) of C3b via FH and MCP. These results were used to map the putative binding regions of C3b involved in the interaction with MCP and CR1 and interrogated relative to known FH binding sites. Seventy-six percent of patients with C3 mutations had low C3 levels that correlated with disease severity. This study expands our knowledge of the functional consequences of aHUS-associated C3 mutations relative to the interaction of C3 with complement regulatory proteins mediating cofactor activity. PMID:25608561

  3. Establishing a Research Center: The Minority Male Community College Collaborative (M2C3)

    ERIC Educational Resources Information Center

    Wood, J. Luke; Urias, Marissa Vasquez; Harris, Frank, III

    2016-01-01

    This chapter describes the establishment of the Minority Male Community College Collaborative (M2C3), a research and practice center at San Diego State University. M2C3 partners with community colleges across the United States to enhance access, achievement, and success among men of color. This chapter begins with a description of the national…

  4. 21 CFR 866.5260 - Complement C3b inactivator immunological test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5260 Complement C3b inactivator immunological test system. (a) Identification. A complement... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Complement C3b inactivator immunological...

  5. ClC-3 chloride channel functions as a mechanically sensitive channel in osteoblasts.

    PubMed

    Wang, Huan; Wang, Rong; Wang, Zhe; Liu, Qian; Mao, Yong; Duan, Xiaohong

    2015-12-01

    Mechanical stimulation usually causes the volume changes of osteoblasts. Whether these volume changes could be sensed by the ClC-3 chloride channel, a volume-sensitive ion channel, and further promote the osteodifferentiation in osteoblasts has not been determined. In this study, we applied persistent static compression on MC3T3-E1 cells to detect the expression changes of ClC-3, osteogenic markers, as well as some molecules related with signaling transduction pathway. We tested the key role of ClC-3 in transferring the mechanical signal to osteoinduction by ClC-3 overexpressing and siRNA technique. We found that ClC-3 level was up-regulated by mechanical stimulation in MC3T3-E1 cells. Mechanical force also up-regulated the mRNA level of osteogenic markers such as alkaline phosphatase (Alp), bone sialoprotein (Bsp), and osteocalcin (Oc), which could be blocked or strengthened by Clcn3 siRNA or overexpressing, and Alp expression was more sensitive to the changes of ClC-3 level. We also found that runt-related transcription factor 2 (Runx2), transforming growth factor beta 1 (TGF-β1), and Wnt pathway might be involved in ClC-3 mediated mechanical transduction in osteoblasts. The data from the current study suggest that the ClC-3 chloride channel acts as a mechanically sensitive channel to regulate osteodifferentiation in osteoblasts.

  6. The role of aldo-keto reductase 1C3 (AKR1C3)-mediated prostaglandin D2 (PGD2) metabolism in keloids.

    PubMed

    Mantel, Alon; Newsome, Austin; Thekkudan, Theresa; Frazier, Robert; Katdare, Meena

    2016-01-01

    Keloids are progressively expanding scars, mostly prevalent in individuals of African descent. Previous data identified increased mast cell number and activation state in keloids suggesting a role in disease progression. The major eicosanoid secreted by mast cells is prostaglandin D2 (PGD2), a relatively unstable pro-inflammatory mediator which can be spontaneously converted to 15-deoxy-(Delta12,14)-prostaglandin J2(15d-PGJ2) or enzymatically metabolized to 9α,11β-PGF2 by aldo-keto reductase 1C3 (AKR1C3). In this work, we investigated the possible role of PGD2 and its metabolites in keloids using CRL1762 keloid fibroblasts (KF) and immunohistochemical staining. Our data suggested approximately 3-fold increase of tryptase-positive mast cell count in keloids compared with normal skin. Furthermore, AKR1C3 was overexpressed in the fibrotic area of keloids while relatively weak staining detected in normal skin. Metabolism of PGD2 to 9α,11β-PGF2 by both, KF and normal fibroblasts, was dependent on AKR1C3 as this reaction was attenuated in the presence of the AKR1C3 inhibitor, 2'-hydroxyflavanone, or in cells with decreased AKR1C3 expression. 15d-PGJ2, but not the other tested PGs, inhibited KF proliferation, attenuated KF-mediated collagen gel contraction and increased caspase-3 activation. In addition, treatment with 15d-PGJ2 activated P38-MAPK, induced reactive oxygen species and upregulated superoxide dismutase-1 (SOD-1). Finally, inhibition of P38-MAPK further augmented 15d-PGJ2-induced caspase-3 cleavage and attenuated its effect on SOD-1 transcription. This work suggests that localized dual inhibition of AKR1C3 and P38-MAPK may inhibit keloid progression. Inhibiting AKR1C3 activity may generate oxidative environment due to redirection of PGD2 metabolism towards 15d-PGJ2 while inhibition of P38-MAPK will sensitize keloid cells to ROS-induced apoptosis. PMID:26308156

  7. Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H8O Propan-1-ol (VMSD1111, LB4910_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H8O Propan-1-ol (VMSD1111, LB4910_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  8. Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H7NO N,N-Dimethylmethanamide (VMSD1511, LB4265_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume A 'Binary Liquid Systems of Nonelectrolytes I' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H7NO N,N-Dimethylmethanamide (VMSD1511, LB4265_V)' providing data from direct measurement of low-pressure thermodynamic speed of sound at variable mole fraction and constant temperature, in the single-phase region(s).

  9. Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H7NO N,N-Dimethylmethanamide (VMSD1212, LB4259_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume A 'Binary Liquid Systems of Nonelectrolytes I' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H7NO N,N-Dimethylmethanamide (VMSD1212, LB4259_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  10. Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H7NO N,N-Dimethylmethanamide (VMSD1111, LB4254_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume A 'Binary Liquid Systems of Nonelectrolytes I' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H7NO N,N-Dimethylmethanamide (VMSD1111, LB4254_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  11. Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H8O Propan-1-ol (VMSD1212, LB4918_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H8O Propan-1-ol (VMSD1212, LB4918_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  12. Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H6O2 Methyl ethanoate (VMSD1511, LB4267_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H6O2 Methyl ethanoate (VMSD1511, LB4267_V)' providing data from direct measurement of low-pressure thermodynamic speed of sound at variable mole fraction and constant temperature, in the single-phase region(s).

  13. Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H6O2 Methyl ethanoate (VMSD1412, LB4273_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H6O2 Methyl ethanoate (VMSD1412, LB4273_V)' providing data by calculation of isentropic compressibility from low-pressure density and thermodynamic speed of sound data at variable mole fraction and constant temperature, in the single-phase region(s).

  14. Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H7NO N,N-Dimethylmethanamide (VMSD1412, LB4271_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume A 'Binary Liquid Systems of Nonelectrolytes I' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H7NO N,N-Dimethylmethanamide (VMSD1412, LB4271_V)' providing data by calculation of isentropic compressibility from low-pressure density and thermodynamic speed of sound data at variable mole fraction and constant temperature, in the single-phase region(s).

  15. Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H6O2 Methyl ethanoate (VMSD1111, LB4251_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H6O2 Methyl ethanoate (VMSD1111, LB4251_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  16. Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H8O Propan-1-ol (VMSD1511, LB4926_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H8O Propan-1-ol (VMSD1511, LB4926_V)' providing data from direct measurement of low-pressure thermodynamic speed of sound at variable mole fraction and constant temperature, in the single-phase region(s).

  17. Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H6O2 Methyl ethanoate (VMSD1212, LB4261_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H6O2 Methyl ethanoate (VMSD1212, LB4261_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  18. A comparison of the infrared multiphoton dissociation of C 3H 5C(CH 3) 3 and C 3H 5Ge(CH 3) 3

    NASA Astrophysics Data System (ADS)

    Zhitneva, G. P.

    1999-07-01

    The CO 2 laser-induced multiphoton dissociation (MPD) of C 3H 5X(CH 3) 3 molecules (X=C or Ge) in the gas phase was studied. Average energy absorbed by molecules with C at dissociation threshold is higher than that for Ge-containing molecules. The dependence of fragmentation probability of X(CH 3) 3, formed from MPD of C 3H 5X(CH 3) 3, on the laser fluence is different for molecules with C or Ge. The distinctions in MPD of these molecules can be attributed to the heavy-atom effect on the vibrational energy transfer over the molecule.

  19. Haplotypes in the APOA1-C3-A4-A5 gene cluster affect plasma lipids in both humans and baboons.

    PubMed

    Wang, Qian-fei; Liu, Xin; O'Connell, Jeff; Peng, Ze; Krauss, Ronald M; Rainwater, David L; VandeBerg, John L; Rubin, Edward M; Cheng, Jan-Fang; Pennacchio, Len A

    2004-05-15

    Genetic studies in non-human primates serve as a potential strategy for identifying genomic intervals where polymorphisms impact upon human disease-related phenotypes. It remains unclear, however, whether independently arising polymorphisms in orthologous regions of non-human primates leads to similar variation in a quantitative trait found in both species. To explore this paradigm, we studied a baboon apolipoprotein gene cluster (APOA1/C3/A4/A5) for which the human gene orthologs have well-established roles in influencing plasma HDL-cholesterol and triglyceride concentrations. Our extensive polymorphism analysis of this 68 kb gene cluster in 96 pedigreed baboons identified several haplotype blocks each with limited diversity, consistent with haplotype findings in humans. To determine whether baboons, like humans, also have particular haplotypes associated with lipid phenotypes, we genotyped 634 well-characterized baboons using 16 haplotype tagging SNPs. Genetic analysis of single SNPs, as well as haplotypes, revealed an association of APOA5 and APOC3 variants with HDL-cholesterol and triglyceride concentrations, respectively. Thus, independent variation in orthologous genomic intervals does associate with similar quantitative lipid traits in both species, supporting the possibility of uncovering human quantitative trait loci genes in a highly controlled non-human primate model.

  20. Haplotypes in the APOA1-C3-A4-A5 gene cluster affect plasma lipids in both humans and baboons

    SciTech Connect

    Wang, Qian-fei; Liu, Xin; O'Connell, Jeff; Peng, Ze; Krauss, Ronald M.; Rainwater, David L.; VandeBerg, John L.; Rubin, Edward M.; Cheng, Jan-Fang; Pennacchio, Len A.

    2003-09-15

    Genetic studies in non-human primates serve as a potential strategy for identifying genomic intervals where polymorphisms impact upon human disease-related phenotypes. It remains unclear, however, whether independently arising polymorphisms in orthologous regions of non-human primates leads to similar variation in a quantitative trait found in both species. To explore this paradigm, we studied a baboon apolipoprotein gene cluster (APOA1/C3/A4/A5) for which the human gene orthologs have well established roles in influencing plasma HDL-cholesterol and triglyceride concentrations. Our extensive polymorphism analysis of this 68 kb gene cluster in 96 pedigreed baboons identified several haplotype blocks each with limited diversity, consistent with haplotype findings in humans. To determine whether baboons, like humans, also have particular haplotypes associated with lipid phenotypes, we genotyped 634 well characterized baboons using 16 haplotype tagging SNPs. Genetic analysis of single SNPs, as well as haplotypes, revealed an association of APOA5 and APOC3 variants with HDL cholesterol and triglyceride concentrations, respectively. Thus, independent variation in orthologous genomic intervals does associate with similar quantitative lipid traits in both species, supporting the possibility of uncovering human QTL genes in a highly controlled non-human primate model.

  1. Complement C3-Deficient Mice Fail to Display Age-Related Hippocampal Decline.

    PubMed

    Shi, Qiaoqiao; Colodner, Kenneth J; Matousek, Sarah B; Merry, Katherine; Hong, Soyon; Kenison, Jessica E; Frost, Jeffrey L; Le, Kevin X; Li, Shaomin; Dodart, Jean-Cosme; Caldarone, Barbara J; Stevens, Beth; Lemere, Cynthia A

    2015-09-23

    The complement system is part of the innate immune response responsible for removing pathogens and cellular debris, in addition to helping to refine CNS neuronal connections via microglia-mediated pruning of inappropriate synapses during brain development. However, less is known about the role of complement during normal aging. Here, we studied the role of the central complement component, C3, in synaptic health and aging. We examined behavior as well as electrophysiological, synaptic, and neuronal changes in the brains of C3-deficient male mice (C3 KO) compared with age-, strain-, and gender-matched C57BL/6J (wild-type, WT) control mice at postnatal day 30, 4 months, and 16 months of age. We found the following: (1) region-specific and age-dependent synapse loss in aged WT mice that was not observed in C3 KO mice; (2) age-dependent neuron loss in hippocampal CA3 (but not in CA1) that followed synapse loss in aged WT mice, neither of which were observed in aged C3 KO mice; and (3) significantly enhanced LTP and cognition and less anxiety in aged C3 KO mice compared with aged WT mice. Importantly, CA3 synaptic puncta were similar between WT and C3 KO mice at P30. Together, our results suggest a novel and prominent role for complement protein C3 in mediating aged-related and region-specific changes in synaptic function and plasticity in the aging brain. Significance statement: The complement cascade, part of the innate immune response to remove pathogens, also plays a role in synaptic refinement during brain development by the removal of weak synapses. We investigated whether complement C3, a central component, affects synapse loss during aging. Wild-type (WT) and C3 knock-out (C3 KO) mice were examined at different ages. The mice were similar at 1 month of age. However, with aging, WT mice lost synapses in specific brain regions, especially in hippocampus, an area important for memory, whereas C3 KO mice were protected. Aged C3 KO mice also performed better on

  2. Disappearing Polymorphs Revisited

    PubMed Central

    Bučar, Dejan-Krešimir; Lancaster, Robert W; Bernstein, Joel

    2015-01-01

    Nearly twenty years ago, Dunitz and Bernstein described a selection of intriguing cases of polymorphs that disappear. The inability to obtain a crystal form that has previously been prepared is indeed a frustrating and potentially serious problem for solid-state scientists. This Review discusses recent occurrences and examples of disappearing polymorphs (as well as the emergence of elusive crystal forms) to demonstrate the enduring relevance of this troublesome, but always captivating, phenomenon in solid-state research. A number of these instances have been central issues in patent litigations. This Review, therefore, also highlights the complex relationship between crystal chemistry and the law. PMID:26031248

  3. Structural transitions of complement component C3 and its activation products

    PubMed Central

    Nishida, Noritaka; Walz, Thomas; Springer, Timothy A.

    2006-01-01

    Complement sensitizes pathogens for phagocytosis and lysis. We use electron microscopy to examine the structural transitions in the activation of the pivotal protein in the complement pathway, C3. In the cleavage product C3b, the position of the thioester domain moves ≈100 Å, which becomes covalently coupled to antigenic surfaces. In the iC3b fragment, cleavage in an intervening domain creates a long flexible linker between the thioester domain and the macroglobulin domain ring of C3. Studies on two products of nucleophile addition to C3 reveal a structural intermediate in activation, and a final product, in which the anaphylatoxin domain has undergone a remarkable movement through the macroglobulin ring. PMID:17172439

  4. Convergence of potential net ecosystem production among contrasting C3 grasslands

    PubMed Central

    Peichl, Matthias; Sonnentag, Oliver; Wohlfahrt, Georg; Flanagan, Lawrence B.; Baldocchi, Dennis D.; Kiely, Gerard; Galvagno, Marta; Gianelle, Damiano; Marcolla, Barbara; Pio, Casimiro; Migliavacca, Mirco; Jones, Michael B.; Saunders, Matthew

    2013-01-01

    Metabolic theory and body size dependent constraints on biomass production and decomposition suggest that differences in the intrinsic potential net ecosystem production (NEPPOT) should be small among contrasting C3 grasslands and therefore unable to explain the wide range in the annual apparent net ecosystem production (NEPAPP) reported by previous studies. We estimated NEPPOT for nine C3 grasslands under contrasting climate and management regimes using multi-year eddy covariance data. NEPPOT converged within a narrow range suggesting little difference in the net carbon dioxide uptake capacity across C3 grasslands. Our results indicate a unique feature of C3 grasslands compared to other terrestrial ecosystems and suggest a state of stability in NEPPOT due to tightly coupled production and respiration processes. Consequently, the annual NEPAPP of C3 grasslands is primarily a function of seasonal and short-term environmental and management constraints, and therefore especially susceptible to changes in future climate patterns and associated adaptation of management practices. PMID:23346985

  5. Influence of Si ion implantation on structure and morphology of g-C3N4

    NASA Astrophysics Data System (ADS)

    Varalakshmi, B.; Sreenivasulu, K. V.; Asokan, K.; Srikanth, V. V. S. S.

    2016-07-01

    Effect of Si ion implantation on structural and morphological features of graphite-like carbon nitride (g-C3N4) was investigated. g-C3N4 was prepared by using a simple atmospheric thermal decomposition process. The g-C3N4 pellets were irradiated with a Si ion beam of energy 200 keV with different fluencies. Structural, morphological and elemental, and phase analysis of the implanted samples in comparison with the pristine samples was carried out by using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) with energy dispersive spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR) techniques, respectively. The observations revealed that Si ion implantation results in a negligible change in the crystallite size and alteration of the network-like to the sheet-like morphology of g-C3N4 and Si ions in the g-C3N4 network.

  6. A simple method for the production of anti-C3d monoclonal antibody.

    PubMed

    Cruz, Carlos; León, Graciela

    2007-12-01

    Production of monoclonal antibodies to C3d usually involves the purification of protein. Our method does not require C3 purification; it relies on attachment of C3b to mouse erythrocytes by activation of alternative pathways and further conversion in C3d. We prepared human complement-coated mouse red cells and sensitized mice of the same strain with our own schedule of immunization and applied the classical methods to obtain a mouse monoclonal antibody. We obtained a clone called BMS-11 which produces a monoclonal antibody of IgM class, to C3d with a title of 1:500000. The monoclonal antibody obtained has shown that it is suitable for use as an antiglobulin reagent.

  7. Studies on the haemolytic activity of circulating C1q-C3/C4 complexes.

    PubMed

    Wouters, Diana; Brouwer, Mieke C; Daha, Mohamed R; Hack, C Erik

    2008-04-01

    During classical complement pathway activation, the internal thio-ester of both C3 and C4 becomes exposed which enables C3 and C4 to bind covalently to nearby molecules. Recently, we described that C3 and C4 bind to C1q, the recognition molecule of the classical pathway, upon activation of this pathway. Covalently linked complexes between C1q and activated C4 (C1q-C4 complexes) are specific markers for classical complement pathway activation. In the present study we further investigated the molecular characteristics of complexes between C1q and activated C3 or C4 that occur in vivo. In human serum only complexes of C1q with C3d or C4d fragments were detected but not those with the larger C3b/bi or C4b/bi fragments. We identified that C1q-C4 complexes circulate as part of the intact C1 complex instead of as free C1q. Finally, we investigated whether deposited C3d or C4d affect C1 haemolytic activity. We observed that both C1q-C3 and C1q-C4 complexes are significantly (P<0.05) less active in a C1q-haemolytic assay than non-complexed C1q. Thus, the dominant types of C1q complexes that circulate in vivo are C1q-C3d and C1q-C4d complexes. These complexes are still able to interact with C1r and C1s to form a C1 complex, but seem to have a reduced activity as compared to C1q not carrying C3- or C4-fragments.

  8. The ClC-3 chloride channel and osmoregulation in the European sea bass, Dicentrarchus labrax.

    PubMed

    Bossus, Maryline; Charmantier, Guy; Blondeau-Bidet, Eva; Valletta, Bianca; Boulo, Viviane; Lorin-Nebel, Catherine

    2013-07-01

    Dicentrarchus labrax migrates between sea (SW), brackish and fresh water (FW) where chloride concentrations and requirements for chloride handling change: in FW, fish absorb chloride and restrict renal losses; in SW, they excrete chloride. In this study, the expression and localization of ClC-3 and Na(+)/K(+)-ATPase (NKA) were studied in fish adapted to SW, or exposed to FW from 10 min to 30 days. In gills, NKA-α1 subunit expression transiently increased from 10 min and reached a stabilized intermediate expression level after 24 h in FW. ClC-3 co-localized with NKA in the basolateral membrane of mitochondria-rich cells (MRCs) at all conditions. The intensity of MRC ClC-3 immunostaining was significantly higher (by 50 %) 1 h after the transfer to FW, whereas the branchial ClC-3 protein expression was 30 % higher 7 days after the transfer as compared to SW. This is consistent with the increased number of immunopositive MRCs (immunostained for NKA and ClC-3). However, the ClC-3 mRNA expression was significantly lower in FW gills. In the kidney, after FW transfer, a transient decrease in NKA-α1 subunit expression was followed by significantly higher stable levels from 24 h. The low ClC-3 protein expression detected at both salinities was not observed by immunocytochemistry in the SW kidney; ClC-3 was localized in the basal membrane of the collecting ducts and tubules 7 and 30 days after transfer to FW. Renal ClC-3 mRNA expression, however, seemed higher in SW than in FW. The potential role of this chloride channel ClC-3 in osmoregulatory and osmosensing mechanisms is discussed.

  9. The Y-chromosome C3* star-cluster attributed to Genghis Khan's descendants is present at high frequency in the Kerey clan from Kazakhstan.

    PubMed

    Abilev, Serikbai; Malyarchuk, Boris; Derenko, Miroslava; Wozniak, Marcin; Grzybowski, Tomasz; Zakharov, Ilya

    2012-02-01

    To verify the possibility that the Y-chromosome C3* star-cluster attributed to Genghis Khan and his patrilineal descendants is relatively frequent in the Kereys, who are the dominant clan in Kazakhstan and in Central Asia as a whole, polymorphism of the Y-chromosome was studied in Kazakhs, represented mostly by members of the Kerey clan. The Kereys showed the highest frequency (76.5%) of individuals carrying the Y-chromosome variant known as C3* star-cluster ascribed to the descendants of Genghis Khan. C3* star-cluster haplotypes were found in two subclans, Abakh-Kereys and Ashmaily-Kereys, diverged about 20-22 generations ago according to the historical data. Median network of the Kerey star-cluster haplotypes at 17 STR loci displays a bipartite structure, with two subclusters defined by the only difference at the DYS448 locus. Noteworthy is a strong correspondence of these subclusters with the Kerey subclans affiliation. The data obtained suggest that the Kerey clan appears to be the largest known clan in the world descending from a common Y-chromosome ancestor. Possible ways of Genghis Khan's relationship to the Kereys are discussed.

  10. 17 CFR 240.15c3-1a - Options (Appendix A to 17 CFR 240.15c3-1).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Options (Appendix A to 17 CFR... Options (Appendix A to 17 CFR 240.15c3-1). (a) Definitions. (1) The term unlisted option shall mean any... determined that a percentage of offsetting profits may be applied to losses at the same valuation point....

  11. Crossed-beam radical-radical reaction dynamics of O(3P)+C3H3-->H(2S)+C3H2O

    NASA Astrophysics Data System (ADS)

    Kwon, Lee-Kyoung; Nam, Mi-Ja; Youn, Sung-Eui; Joo, Sun-Kyu; Lee, Hohjai; Choi, Jong-Ho

    2006-05-01

    The radical-radical oxidation reaction, O(P3)+C3H3(propargyl)→H(S2)+C3H2O (propynal), was investigated using vacuum-ultraviolet laser-induced fluorescence spectroscopy in a crossed-beam configuration, together with ab initio and statistical calculations. The barrierless addition of O(P3) to C3H3 is calculated to form energy-rich addition complexes on the lowest doublet potential energy surface, which subsequently undergo direct decomposition steps leading to the major reaction products, H +C3H2O (propynal). According to the nascent H-atom Doppler-profile analysis, the average translational energy of the products and the fraction of the average transitional energy to the total available energy were determined to be 5.09±0.36kcal/mol and 0.077, respectively. On the basis of a comparison with statistical prior calculations, the reaction mechanism and the significant internal excitation of the polyatomic propynal product can be rationalized in terms of the formation of highly activated, short-lived addition-complex intermediates and the adiabaticity of the excess available energy along the reaction coordinate.

  12. 17 CFR 240.15c3-1a - Options (Appendix A to 17 CFR 240.15c3-1).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... terms theoretical gains and losses shall mean the gain and loss in the value of individual option series... 17 Commodity and Securities Exchanges 3 2013-04-01 2013-04-01 false Options (Appendix A to 17 CFR... Options (Appendix A to 17 CFR 240.15c3-1). (a) Definitions. (1) The term unlisted option shall mean...

  13. 17 CFR 240.15c3-1a - Options (Appendix A to 17 CFR 240.15c3-1).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... terms theoretical gains and losses shall mean the gain and loss in the value of individual option series... 17 Commodity and Securities Exchanges 3 2011-04-01 2011-04-01 false Options (Appendix A to 17 CFR... Options (Appendix A to 17 CFR 240.15c3-1). (a) Definitions. (1) The term unlisted option shall mean...

  14. 17 CFR 240.15c3-1a - Options (Appendix A to 17 CFR 240.15c3-1).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... terms theoretical gains and losses shall mean the gain and loss in the value of individual option series... 17 Commodity and Securities Exchanges 3 2012-04-01 2012-04-01 false Options (Appendix A to 17 CFR... Options (Appendix A to 17 CFR 240.15c3-1). (a) Definitions. (1) The term unlisted option shall mean...

  15. Diosgenone: a second P21 polymorph

    PubMed Central

    Hernández Linares, María-Guadalupe; Guerrero-Luna, Gabriel; Bernès, Sylvain; Flores-Alamo, Marcos; Fernández-Herrera, María A.

    2012-01-01

    Diosgenone [(20S,22R,25R)-spirost-4-en-3-one, C27H40O3] has been proposed as a new therapeutic alternative for the treatment of malaria. The first X-ray structure report for diosgenone was by Piro et al. [(2002). Z. Naturforsch. Teil C, 57, 947–950] in the space group P21 (Z′ = 2). We now report a new polymorph in the same space group, with two mol­ecules in the asymmetric unit. Both mol­ecules have similar conformations, characterized by a skewed envelope A ring, which contains the C=C bond conjugated with the ketone functionality at C3. The dimorphism results from a modification of the relative orientation of the mol­ecules in the asymmetric unit: two independent mol­ecules were arranged anti­parallel in the Piro report, while they are parallel in the present determination. PMID:22904824

  16. Enzyme polymorphisms in Canarium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fifty-two accessions of Canarium involving seven species, C. ovatum, C. album, C. megalanthum, C. harveyi, C. indicum, C. mehenbethene, and C. odontophyllum were studied for isozyme polymorphisms. Starch gel electrophoresis with a histidine-citrate buffer system (pH 6.5) was employed to assay six en...

  17. Polymorphous Perversity in Texts

    ERIC Educational Resources Information Center

    Johnson-Eilola, Johndan

    2012-01-01

    Here's the tricky part: If we teach ourselves and our students that texts are made to be broken apart, remixed, remade, do we lose the polymorphous perversity that brought us pleasure in the first place? Does the pleasure of transgression evaporate when the borders are opened?

  18. Polymorphism of sorbitol

    NASA Astrophysics Data System (ADS)

    Nezzal, Amale; Aerts, Luc; Verspaille, Marleen; Henderickx, Geert; Redl, Andreas

    2009-07-01

    The polymorphism of sorbitol was investigated, confirming the existence of four anhydrous crystalline phases plus the hydrate. The crystallised melt (CM), the alpha form, and the gamma form were obtained via a dry route. The CM was confirmed to be a crystalline state with a spherulite morphology. The alpha form was obtained via direct conversion from the CM, in contrast to more complicated routes previously reported, and was found to have a very high crystallinity. Gamma crystals were obtained by seeding the melt at high temperature; however, crystallinity was clearly less than for alpha crystals. Despite its lower crystallinity, the gamma polymorph was found to be the most stable of the anhydrous crystalline forms; this was confirmed by its high melting point and low hygroscopicity. In contrast, the alpha polymorph has a relatively high melting point but lacks moisture stability at high relative humidity. The hydrate form has the same resistance to moisture as the gamma form, but melts at a lower temperature. The combination of both a high melting point and high stability in the presence of water makes the gamma polymorph best suited for confectionary applications.

  19. Investigation of Uranium Polymorphs

    SciTech Connect

    Sweet, Lucas E.; Henager, Charles H.; Hu, Shenyang Y.; Johnson, Timothy J.; Meier, David E.; Peper, Shane M.; Schwantes, Jon M.

    2011-08-01

    The UO3-water system is complex and has not been fully characterized, even though these species are common throughout the nuclear fuel cycle. As an example, most production schemes for UO3 result in a mixture of up to six or more different polymorphic phases, and small differences in these conditions will affect phase genesis that ultimately result in measureable changes to the end product. As a result, this feature of the UO3-water system may be useful as a means for determining process history. This research effort attempts to better characterize the UO3-water system with a variety of optical techniques for the purpose of developing some predictive capability for estimating process history in polymorphic phases of unknown origin. Three commercially relevant preparation methods for the production of UO3 were explored. Previously unreported low temperature routes to β- and γ-UO3 were discovered. Raman and fluorescence spectroscopic libraries were established for pure and mixed polymorphic forms of UO3 in addition to the common hydrolysis products of UO3. An advantage of the sensitivity of optical fluorescence microscopy over XRD has been demonstrated. Preliminary aging studies of the α and γ forms of UO3 have been conducted. In addition, development of a 3-D phase field model used to predict phase genesis of the system was initiated. Thermodynamic and structural constants that will feed the model have been gathered from the literature for most of the UO3 polymorphic phases.

  20. High-yield synthesis and optical properties of g-C3N4

    NASA Astrophysics Data System (ADS)

    Yuan, Yanwen; Zhang, Lulu; Xing, Jun; Utama, M. Iqbal Bakti; Lu, Xin; Du, Kezhao; Li, Yongmei; Hu, Xiao; Wang, Shijie; Genç, Aziz; Dunin-Borkowski, Rafal; Arbiol, Jordi; Xiong, Qihua

    2015-07-01

    Graphitic carbon nitride (g-C3N4), a metal-free semiconductor with a band gap of 2.7 eV, has received considerable attention owing to its fascinating photocatalytic performances under visible-light. g-C3N4 exhibits high thermal and chemical stability and non-toxicity such that it has been considered as the most promising photocatalyst for environmental improvement and energy conservation. Hence, it is of great importance to obtain high-quality g-C3N4 and gain a clear understanding of its optical properties. Herein, we report a high-yield synthesis of g-C3N4 products via heating of high vacuum-sealed melamine powder in an ampoule at temperatures between 450 and 650 °C. Using transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), electron energy loss spectroscopy (EELS), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), the chemical composition and crystallization of the as-produced g-C3N4 are demonstrated. A systematic optical study of g-C3N4 is carried out with several approaches. The optical phonon behavior of g-C3N4 is revealed by infrared and Raman spectroscopy, and the emission properties of g-C3N4 are investigated using photoluminescence (PL) spectroscopy, while the photocatalytic properties are explored by the photodegradation experiment.Graphitic carbon nitride (g-C3N4), a metal-free semiconductor with a band gap of 2.7 eV, has received considerable attention owing to its fascinating photocatalytic performances under visible-light. g-C3N4 exhibits high thermal and chemical stability and non-toxicity such that it has been considered as the most promising photocatalyst for environmental improvement and energy conservation. Hence, it is of great importance to obtain high-quality g-C3N4 and gain a clear understanding of its optical properties. Herein, we report a high-yield synthesis of g-C3N4 products via heating of high vacuum-sealed melamine powder in an ampoule at

  1. C3-OH of Amphotericin B Plays an Important Role in Ion Conductance.

    PubMed

    Davis, Stephen A; Della Ripa, Lisa A; Hu, Lingbowei; Cioffi, Alexander G; Pogorelov, Taras V; Rienstra, Chad M; Burke, Martin D

    2015-12-01

    Amphotericin B (AmB) is the archetype for small molecules that form ion channels in living systems and has recently been shown to replace a missing protein ion transporter and thereby restore physiology in yeast. Molecular modeling studies predict that AmB self-assembles in lipid membranes with the polyol region lining a channel interior that funnels to its narrowest region at the C3-hydroxyl group. This model predicts that modification of this functional group would alter conductance of the AmB ion channel. To test this hypothesis, the C3-hydroxyl group was synthetically deleted, and the resulting derivative, C3deoxyAmB (C3deOAmB), was characterized using multidimensional NMR experiments and single ion channel electrophysiology recordings. C3deOAmB possesses the same macrocycle conformation as AmB and retains the capacity to form transmembrane ion channels, yet the conductance of the C3deOAmB channels is 3-fold lower than that of AmB channels. Thus, the C3-hydroxyl group plays an important role in AmB ion channel conductance, and synthetic modifications at this position may provide an opportunity for further tuning of channel functions. PMID:26580003

  2. The C3-OH of Amphotericin B Plays an Important Role in Ion Conductance

    PubMed Central

    Davis, Stephen A.; Della Ripa, Lisa A.; Hu, Lingbowei; Cioffi, Alexander G.; Pogorelov, Taras V.; Rienstra, Chad M.; Burke, Martin D.

    2015-01-01

    Amphotericin B (AmB) is the archetype for small molecules that form ion channels in living systems, and has recently been shown to replace a missing protein ion transporter and thereby restore physiology in yeast. Molecular modeling studies predict that AmB self-assembles in lipid membranes with the polyol region lining a channel interior that funnels to its narrowest region at the C3-hydroxyl group. This model predicts that modification of this functional group would alter conductance of the AmB ion channel. To test this hypothesis, the C3-hydroxyl group was synthetically deleted and the resulting derivative, C3deoxyAmB (C3deOAmB), was characterized using multidimensional NMR experiments and single ion channel electrophysiology recordings. C3deOAmB possesses the same macrocycle conformation as AmB and retains the capacity to form transmembrane ion channels, yet the conductance of the C3deOAmB channels is threefold lower than that of AmB channels. Thus, the C3-hydroxyl group plays an important role in AmB ion channel conductance, and synthetic modifications at this position may provide an opportunity for further tuning of channel functions. PMID:26580003

  3. Discovery of Small Molecules for Fluorescent Detection of Complement Activation Product C3d.

    PubMed

    Gorham, Ronald D; Nuñez, Vicente; Lin, Jung-Hsin; Rooijakkers, Suzan H M; Vullev, Valentine I; Morikis, Dimitrios

    2015-12-24

    Complement activation plays a major role in many acute and chronic inflammatory conditions. C3d, a terminal product of complement activation, remains covalently attached to cells and is an excellent biomarker of complement-mediated inflammation. We employed a virtual high-throughput screening protocol to identify molecules with predicted binding to complement C3d and with intrinsic fluorescence properties to enable detection. Pharmacophore models were developed based on known C3d-ligand interactions and information from computational analysis of structural and molecular dynamics data. Iterative pharmacophore-based virtual screening was performed to identify druglike molecules with physicochemical similarity to the natural C3d ligand CR2. Hits from the pharmacophore screens were docked to C3d and ranked based on predicted binding free energies. Top-ranked molecules were selected for experimental validation of binding affinity to C3d, using microscale thermophoresis, and for their suitability to become molecular imaging agents, using fluorescence spectroscopy. This work serves as a foundation for identifying additional fluorescent molecules with high-affinity for C3d that will subsequently be explored as noninvasive in vivo diagnostics of complement-mediated inflammation, for spatiotemporal monitoring of disease progression, and for targeting therapeutics to sites of inflammation.

  4. C3d enhanced DNA vaccination induced humoral immune response to glycoprotein C of pseudorabies virus

    SciTech Connect

    Tong Tiezhu; Fan Huiying; Tan Yadi; Xiao Shaobo; Ling Jieyu; Chen Huanchun; Guo Aizhen . E-mail: aizhen@mail.hzau.edu.cn

    2006-09-08

    Murine C3d were utilized to enhance immunogenicity of pseudorabies virus (PrV) gC DNA vaccination. Three copies of C3d and four copies of CR2-binding domain M28{sub 4} were fused, respectively, to truncated gC gene encoding soluble glycoprotein C (sgC) in pcDNA3.1. BALB/c mice were, respectively, immunized with recombinant plasmids, blank vector, and inactivated vaccine. The antibody ELISA titer for sgC-C3d{sub 3} DNA was 49-fold more than that for sgC DNA, and the neutralizing antibody obtained 8-fold rise. Protection of mice from death after lethal PrV (316 LD{sub 5}) challenge was augmented from 25% to 100%. Furthermore, C3d fusion increased Th2-biased immune response by inducing IL-4 production. The IL-4 level for sgC-C3d{sub 3} DNA immunization approached that for the inactivated vaccine. Compared to C3d, M28 enhanced sgC DNA immunogenicity to a lesser extent. In conclusion, we demonstrated that murine C3d fusion significantly enhanced gC DNA immunity by directing Th1-biased to a balanced and more effective Th1/Th2 response.

  5. Fabrication and Characterization of AL-AL4C3 Nanocomposite by Mechanical Alloying

    NASA Astrophysics Data System (ADS)

    Mohammad Sharifi, E.; Enayati, M. H.; Karimzadeh, F.

    Aluminum carbide (Al4C3) seems to be an ideal reinforcement for producing aluminum matrix composites. Al4C3 has high hardness and shear strength as well as a high melting point. The dispersion of Al4C3 particles in the matrix produces a pinning effect that reduces aluminum grain growth, which improves the mechanical properties. In this study, aluminum powders were mixed with 4.5 wt.% graphite and mechanically alloyed using a high-energy ball mill in order to produce Al-Al4C3 nanocomposite. The structural evaluation of powder particles after different milling times was studied by X-ray diffractometry, scanning electron microscopy and microhardness measurements. The aluminum crystallite size estimated with broadening of XRD peaks by Williamson-Hall formula. XRD results suggested that the grain size of aluminum decreased to nanometer range (30 nm) during ball milling. No Al4C3 formed during the mechanical alloying process. Milled powders were then annealed at 300-600 °C for 1 h under argon atmosphere. Annealing at temperatures higher than 300 °C led to formation of Al4C3 phase which increased as annealing temperature increased. Aluminum grain size remained in nanometer range after annealing process. The microhardness of powder particles increased after annealing. Both effects are due to the formation of nanosized Al4C3 particles.

  6. Engineering of human complement component C3 for catalytic inhibition of complement.

    PubMed

    Kölln, Johanna; Bredehorst, Reinhard; Spillner, Edzard

    2005-04-15

    As a novel therapeutic approach in complement-mediated pathologies, we recently developed a human C3 derivative capable of obliterating functional complement by a catalytic, non-inhibitory mechanism. In this derivative, the C-terminal region of hC3 was substituted by a 275 amino acid sequence derived from the corresponding sequence of cobra venom factor (CVF), a complement-activating C3b homologue from snake venom. In this study, we replaced shorter C-terminal sequences of hC3 by corresponding CVF sequences to further reduce potential immunogenicity and to identify domains essential for the formation of functionally stable C3 convertases. In one of these derivatives that is still capable of obliterating functional complement in vitro, the non-human portion could be reduced to a small domain located in the C-terminus of different complement proteins. This conserved NTR/C345C motif is known to be involved in assembly of different convertases of the complement system. These results suggest a major role of the C345C domain in the regulation of the half-life of the C3 convertase. Moreover, its overall identity of 96% to human C3 renders this derivative a promising candidate for therapeutic intervention in complement-mediated pathologies. PMID:15790508

  7. Discovery of Small Molecules for Fluorescent Detection of Complement Activation Product C3d.

    PubMed

    Gorham, Ronald D; Nuñez, Vicente; Lin, Jung-Hsin; Rooijakkers, Suzan H M; Vullev, Valentine I; Morikis, Dimitrios

    2015-12-24

    Complement activation plays a major role in many acute and chronic inflammatory conditions. C3d, a terminal product of complement activation, remains covalently attached to cells and is an excellent biomarker of complement-mediated inflammation. We employed a virtual high-throughput screening protocol to identify molecules with predicted binding to complement C3d and with intrinsic fluorescence properties to enable detection. Pharmacophore models were developed based on known C3d-ligand interactions and information from computational analysis of structural and molecular dynamics data. Iterative pharmacophore-based virtual screening was performed to identify druglike molecules with physicochemical similarity to the natural C3d ligand CR2. Hits from the pharmacophore screens were docked to C3d and ranked based on predicted binding free energies. Top-ranked molecules were selected for experimental validation of binding affinity to C3d, using microscale thermophoresis, and for their suitability to become molecular imaging agents, using fluorescence spectroscopy. This work serves as a foundation for identifying additional fluorescent molecules with high-affinity for C3d that will subsequently be explored as noninvasive in vivo diagnostics of complement-mediated inflammation, for spatiotemporal monitoring of disease progression, and for targeting therapeutics to sites of inflammation. PMID:26613117

  8. Structural influence of gene networks on their inference: analysis of C3NET

    PubMed Central

    2011-01-01

    Background The availability of large-scale high-throughput data possesses considerable challenges toward their functional analysis. For this reason gene network inference methods gained considerable interest. However, our current knowledge, especially about the influence of the structure of a gene network on its inference, is limited. Results In this paper we present a comprehensive investigation of the structural influence of gene networks on the inferential characteristics of C3NET - a recently introduced gene network inference algorithm. We employ local as well as global performance metrics in combination with an ensemble approach. The results from our numerical study for various biological and synthetic network structures and simulation conditions, also comparing C3NET with other inference algorithms, lead a multitude of theoretical and practical insights into the working behavior of C3NET. In addition, in order to facilitate the practical usage of C3NET we provide an user-friendly R package, called c3net, and describe its functionality. It is available from https://r-forge.r-project.org/projects/c3net and from the CRAN package repository. Conclusions The availability of gene network inference algorithms with known inferential properties opens a new era of large-scale screening experiments that could be equally beneficial for basic biological and biomedical research with auspicious prospects. The availability of our easy to use software package c3net may contribute to the popularization of such methods. Reviewers This article was reviewed by Lev Klebanov, Joel Bader and Yuriy Gusev. PMID:21696592

  9. Polymorphism of 4-bromobenzophenone.

    PubMed

    Strzhemechny, Mikhail A; Baumer, Vyacheslav N; Avdeenko, Anatoli A; Pyshkin, Oleg S; Romashkin, Roman V; Buravtseva, Lyubov M

    2007-04-01

    A combination of single-crystal and powder X-ray diffractometry was used to study the structure of two polymorphs of 4-bromobenzophenone over the temperature range from 100 to 300 K. One of the polymorphs of the title compound was known previously and its structure has been determined at room temperature [Ebbinghaus et al. (1997). Z. Kristallogr. 212, 339-340]. Two crystal growth methods were employed, one of which (a modification of the Bridgman-Stockbarger technique) resulted in single crystals of a previously unknown structure. The basic physical properties of the stable polymorph are: growth method, from 2-propanol solutions or gradient sublimation; space group, monoclinic P2(1)/c; melting point, T(m) = 355.2 K; X-ray density (at 100 K), D(x) = 1.646 g cm(-3). The same properties of the metastable polymorph (triclinic P\\overline 1 ) are: growth method, modified Bridgman-Stockbarger method; X-ray density (at 100 K), D(x) = 1.645 g cm(-3); T(m) = 354 K. Thermograms suggest that the melting of the metastable form is accompanied by at least a partial crystallization presumably into the monoclinic form; the transformation is therefore monotropic. Analysis of short distances in both polymorphs shows that numerous weak hydrogen bonds of the C-H...pi type ensure additional stabilization within the respective planes normal to the longest dimension of the molecules. The strong temperature dependence of the lattice constants and of the weak bond distances in the monoclinic form suggest that the weak bond interactions might be responsible for both the large thermal expansion within plane bc and the considerable thermal expansion anisotropy. PMID:17374940

  10. Capillary Deposition of Complement C4d and C3d in Chinese Renal Allograft Biopsies

    PubMed Central

    Lv, Rong; Zhang, Wei; Han, Fei; Liu, Guangjun; Xie, Wenqing

    2015-01-01

    Background. C3d is a product of both the classic and the alternative complement cascades; however, few studies have addressed the role of C3d in renal biopsies and its relationship with long-term graft survival rate is not very clear. Methods. 94 patients with biopsy-proven acute rejection episodes were included in the study. We investigated the associations between histological findings, clinical examinations, and outcome. Results. The overall prevalence for C4dPTC and C3dPTC was 42.6% and 29.8%. There was a significant association between C3dPTC and C4dPTC (P < 0.001). C3dPTC and C4dPTC were related with histological types (P = 0.024 and P < 0.001, resp.). The long-term survival rate for C4dPTC positive transplants was lower than that of C4dPTC negative transplants, but it was not statistic significant in our study (P = 0.150). The survival rate of C3dPTC positive group was much lower than the negative group (P = 0.014). Patients with double positives for C4dPTC and C3dPTC exhibited the lowest survival rate significantly different from those of the C3dPTC only and C4dPTC only groups (P = 0.01 and P = 0.0037). Conclusions. This longitudinal cohort study has demonstrated that C3d deposition in the PTC was closely related to renal dysfunction and pathological changes. PMID:25821339

  11. Abundances of C3Hx Hydrocarbons in Titan's Stratosphere from Cassini CIRS

    NASA Astrophysics Data System (ADS)

    Nixon, C. A.; Jennings, D. E.; Bezard, B.; Vinatier, S.; Teanby, N. A.; Sung, K.; Ansty, T. M.; Irwin, P. G.; Gorius, N.; Cottini, V.; Coustenis, A.; Flasar, F. M.

    2014-12-01

    During the ten years since entry into Saturn orbit in 2004, the Cassini spacecraft has made more than 100 close flybys of Titan, measuring the properties of the atmosphere by both in situ and remote sensing techniques. Cassini's Composite Infrared Spectrometer (CIRS) senses the infrared spectrum from 7-1000 μm (1400-10 cm-1), a region which exhibits the vibrational emissions of many different molecular species. CIRS has therefore been able to map the spatial distributions and temporal variations of hydrocarbons, nitriles and other gas species in Titan's atmosphere, yielding information about the chemistry and dynamics. Recently, Nixon et al. (2013) made the first detection of a new stratospheric gas species from Cassini using CIRS - the C3H6 molecule (propene). This filled in a long-time missing link in the chemical picture of Titan's lower atmosphere, since the C3H4 (propyne) and C3H8 (propane) molecules had been detected in 1981 by Voyager 1 IRIS. The inferred abundance of C3H6 is less than both C3H8 and C3H4, and this pattern is repeated also in the C2Hx molecules where C2H4 is less abundant than C2H2 and C2H6. Therefore a pattern emerges whereby: alkanes > alkynes > alkenes within the C2Hx and C3Hx chemical families in the lower stratosphere. We comment on how this trend compares to published photochemical model predictions, and also give updates on the search for C3Hx isomers (allene: CH2CCH2, and cyclopropane: c-C3H6) and C4Hx species using CIRS.

  12. Glomerular C3d as a novel prognostic marker for renal vasculitis.

    PubMed

    Villacorta, Javier; Diaz-Crespo, Francisco; Acevedo, Mercedes; Guerrero, Carmen; Campos-Martin, Yolanda; García-Díaz, Eugenio; Mollejo, Manuela; Fernandez-Juarez, Gema

    2016-10-01

    Pauci-immune necrotizing crescentic glomerulonephritis is the histologic substrate of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. Several studies in animal models have demonstrated the crucial role of complement activation in the pathogenesis of ANCA-associated vasculitis, but only small series have analyzed the prognostic implications of complement glomerular deposits. This study aimed to assess the clinical and prognostic implications of C3d- and C4d-positive glomerular staining in renal vasculitis. Eighty-five patients with a diagnosis of pauci-immune necrotizing crescentic glomerulonephritis were included in the study. C3d and C4d were analyzed by immunohistochemical staining using a polyclonal antibody. The primary predictors were glomerular C3d- and C4d-positive staining. The primary end point was the cumulative percentage of patients who developed end-stage renal disease. Glomerular staining for C3d and C4d was observed in 42 (49.4%) of 85 biopsies and 38 (44.7%) of 85 biopsies, respectively. C3d-positive staining was associated with the severity of renal impairment and with a lower response rate to treatment (P=.003 and P=.04, respectively). Renal survival at 2 and 5 years was 60.9% and 51.8% in C3d-positive patients compared with 87.7% and 78.9% in C3d-negative patients (P=.04). C4d-positive staining did not show any impact in renal outcome. When adjusted by renal function and other histologic parameters, C3d staining remained as an independent predictor for renal survival (hazard ratio, 2.5; 95% confidence interval, 1.1-5.7; P=.03). Therefore, this study demonstrates that C3d-positive glomerular staining is an independent risk factor for the development of end-stage renal disease in ANCA-associated renal vasculitis.

  13. Resonance Raman fingerprinting of multiheme cytochromes from the cytochrome c3 family.

    PubMed

    Di Paolo, Roberto E; Pereira, Patrícia M; Gomes, Inês; Valente, Filipa M A; Pereira, Inês A C; Franco, Ricardo

    2006-03-01

    Resonance Raman (RR) spectroscopy was used to investigate conformational characteristics of the hemes of several ferricytochromes of the cytochrome c3 family, electron transfer proteins isolated from the periplasm and membranes of sulfate-reducing bacteria. Our analysis concentrated on the low-frequency region of the RR spectra, a fingerprint region that includes vibrations for heme-protein C-S bonds [nu(C(a)S)]. It has been proposed that these bonds are directly involved in the electron transfer process. The three groups of tetraheme cytochrome c3 analyzed, namely Type I cytochrome c (3) (TpIc (3)s), Type II cytochrome c (3) (TpIIc (3)s) and Desulfomicrobium cytochromes c3, display different frequency separations for the two nu(C(a)S) lines that are similar among members of each group. These spectral differences correlate with differences in protein structure observed among the three groups of cytochromes c3. Two larger cytochromes of the cytochrome c3 family display RR spectral characteristics for the nu(C(a)S) lines that are closer to TpIIc3 than to TpIc3. Two other multiheme cytochromes from Desulfovibrio that do not belong to the cytochrome c3 family display nu(C(a)S) lines with reverse relative areas in comparison with the latter family. This RR study shows that the small differences in protein structure observed among these cytochrome c3 correlate to differences on the heme-protein bonds, which are likely to have an impact upon the protein function, making RR spectroscopy a sensitive and useful tool for characterizing these cytochromes.

  14. Nociceptive sensitization by complement C5a and C3a in mouse

    PubMed Central

    Jang, Jun Ho; Clark, J. David; Li, Xiangqi; Yorek, Matthew S.; Usachev, Yuriy M.; Brennan, Timothy J.

    2009-01-01

    Activation of the complement system by injury increases inflammation by producing complement fragments C5a and C3a which are able to recruit and activate immune cells. Complement activation may contribute to pain after inflammation and injury. In the present study, we examined whether C5a and C3a elicit nociception when injected into mouse hind paws in vivo, and whether C5a and C3a activate and/or sensitize mechanosensitive nociceptors when applied on peripheral terminals in vitro. We also examined the dorsal root ganglia (DRG) for C5a receptor (C5aR) mRNA and effects of C5a and C3a on intracellular Ca2+ concentration ([Ca2+]i) using Ca2+ imaging. Heat hyperalgesia was elicited by intraplantar injection of C5a, and mechanical hyperalgesia by C5a and C3a. After exposure to either C5a or C3a, C-nociceptors were sensitized to heat as evidenced by an increased proportion of heat responsive fibers, lowered response threshold to heat and increased action potentials during and after heat stimulation. A-nociceptors were activated by complement. However, no change was observed in mechanical responses of A- and C- nociceptors after C5a and C3a application. The presence of C5aR mRNA was detected in DRG. C5a and C3a application elevated [Ca2+]i and facilitated capsaicin-induced [Ca2+]i responses in DRG neurons. The results suggest a potential role for complement fragments C5a and C3a in nociception by activating and sensitizing cutaneous nociceptors. PMID:20031321

  15. Radiological study of C3–C4 level surgical cases of cervical spondylosis

    PubMed Central

    Tomii, Masato; Mizuno, Junichi; Watanabe, Kazuo

    2016-01-01

    Objective: The purpose of this study was to elucidate the pathological characteristics of C3-C4 cervical spondylotic myelopathy (CSM) from the radiological study. Materials and Methods: A total of 31 patients with single level anterior cervical discectomy and fusion (ACDF) at C3-C4 and 46 patients with single level ACDF at C5-C6 were included in this study. We selected C5-C6 level as a representative of the lower cervical level. The C3-C4 and C5-C6 levels were routinely examined to investigate the areas of the vertebral canal, subarachnoid space, and spinal cord in the cervical canal. Results: The clinical study of C3-C4 ACDF patients showed that as for the C3-C4 area, the area of the cervical vertebral canal, the area of the subarachnoid space, and he transverse surface area of the spinal cord were all significantly smaller in C3-C4 ACDF patients than in C5-C6 ACDF patients. Moreover, as for the C5-C6 area, only the area of the subarachnoid space was significantly smaller in C5-C6 ACDF patients than in C3-C4 ACDF patients. Spondylotic changes predominated at both the C3-C4 and C5-C6 levels. However, in the C5-C6 ACDF patients, spondylotic changes tended to predominate only at the operation level at C5-C6. Conclusions: Aging process develops from lower cervical to upper cervical level. Moreover, this static factor in conjunction with dynamic factor (instability) was the causative factors for the CSM in C3-C4 ACDF patients. PMID:27366255

  16. Induced Resistance as a Mechanism of Biological Control by Lysobacter enzymogenes Strain C3.

    PubMed

    Kilic-Ekici, Ozlem; Yuen, Gary Y

    2003-09-01

    ABSTRACT Induced resistance was found to be a mechanism for biological control of leaf spot, caused by Bipolaris sorokiniana, in tall fescue (Festuca arundinacea) using the bacterium Lysobacter enzymogenes strain C3. Resistance elicited by C3 suppressed germination of B. sorokiniana conidia on the phylloplane in addition to reducing the severity of leaf spot. The pathogen-inhibitory effect could be separated from antibiosis by using heat-inactivated cells of C3 that retained no antifungal activity. Application of live or heat-killed cells to tall fescue leaves resulted only in localized resistance confined to the treated leaf, whereas treatment of roots resulted in systemic resistance expressed in the foliage. The effects of foliar and root applications of C3 were long lasting, as evidenced by suppression of conidial germination and leaf spot development even when pathogen inoculation was delayed 15 days after bacterial treatment. When C3 population levels and germination of pathogen conidia was examined on leaf segments, germination percentage was reduced on all segments from C3-treated leaves compared with segments from non-treated leaves, but no dose-response relationship typical of antagonism was found. Induced resistance by C3 was not host or pathogen specific; foliar application of heat-killed C3 cells controlled B. sorokiniana on wheat and also was effective in reducing the severity of brown patch, caused by Rhizoctonia solani, on tall fescue. Treatments of tall fescue foliage or roots with C3 resulted in significantly elevated peroxidase activity compared with the control.

  17. The C3H2 2(20)-2(11) transition: absorption in cold dark clouds.

    PubMed

    Matthews, H E; Madden, S C; Avery, L W; Irvine, W M

    1986-08-15

    The first observations of the 2(20)-2(11) transition of cyclopropenylidene (C3H2) at 21.6 GHz are described. In all cases where it has been detected, the line appears in absorption, showing that this transition is "refrigerated" (i.e., Tex < 2.7 K) in cold dust clouds. These results are compared with those for the 1(10)-1(01) transition of C3H2, and the consequences for the excitation of C3H2 qualitatively discussed.

  18. Elevated NK sensitivity of Raji cells carrying acceptor-bound C3 fragments.

    PubMed

    Kai, C; Sármay, G; Ramos, O; Yefenof, E; Klein, E

    1988-05-01

    The majority of cell lines derived from Burkitt lymphomas carry CR2 on their plasma membrane cell lines of haematopoietic origin can activate C3 present in human serum through the alternative pathway. However, only the lines that carry CR2 were shown to bind C3 fragments. This bond can be either fixation to acceptor sites or attachment to the CR. Our studies with Raji cells showed that when the possibility for the covalent acceptor bond was eliminated by using methylamine (MA)- or zymosan-treated serum, considerably lower amounts of C3 were bound. In the zymosan-treated serum C3 fragments are present that can bind to receptors but their capacity for acceptor bond is absent. These results indicate that when Raji cell are incubated in human serum some of the generated C3 fragments are bound to acceptors and a lower proportion through the specific interaction with complement receptors. Pretreatment of the CR2 carrying cell lines with human serum elevated their sensitivity to the lytic effect of human blood lymphocytes. We showed in this work that MA-treated serum did not induce this elevation. Zymosan-treated serum under conditions that excluded activation of the residual native C3 molecules, i.e., in the presence of EDTA, did not have the enhancing effect either. These results suggest that the increased lytic efficiency imposed by human serum was due to cleavage of C3 molecules by Raji and fixation of the C3 fragments by acceptor sites. Natural killer cells carry CR3; therefore it is likely that the attached C3 fragments bind also to the effector cells. The C3 molecules could elevate thereby the avidity between the target and the lytic lymphocytes. The observation that C3 fragments are not bound to the surface of CR2 negative lines in spite of their capacity to activate C3 suggests that the receptor molecule is either involved in the activation and/or serves also as an acceptor. PMID:3359489

  19. Reduction of U(VI) and Toxic Metals by Desulfovibrio Cytochrome c3

    SciTech Connect

    Wall, Judy D.

    2003-06-01

    The project, ''Reduction of U(VI) and toxic metals by Desulfovibrio cytochrome c3'', is designed to obtain spectroscopic information for or against a functional interaction of cytochrome c3 and uranium in the whole cells. That is, is the cytochrome c3 the uranium reductase? Our approach has been to start with purified cytochrome and determine any unique spectral disturbances during electron flow to U(VI). Then we will attempt to identify these signals emanating from cells actively reducing uranium. This project is being carried out in collaboration with Dr. William Woodruff at the Los Alamos National Laboratory where the spectral experiments are being carried out.

  20. Disruption of the internal thioester bond in the third component of complement (C3) results in the exposure of neodeterminants also present on activation products of C3. An analysis with monoclonal antibodies.

    PubMed

    Hack, C E; Paardekooper, J; Smeenk, R J; Abbink, J; Eerenberg, A J; Nuijens, J H

    1988-09-01

    Hydrolysis of the internal thioester bond in native C3 is thought to be a key event in initiating the alternative pathway of C activation, because the resulting C3(H2O) acquires "C3b-like" properties. Therefore, disruption of the internal thioester bond is probably accompanied by conformational changes in the C3 molecule. In this study, we demonstrate that such conformational changes indeed occur; 7 of the 19 mAb raised against C3 or C3 activation products recognized epitopes exposed on C3(H2O) but not on native C3. One of these epitopes is located on the C3a part, three on the C3c part, and another three on the C3d,g part. Because the 7 mAb bound equally well to C3 incubated either with MgCl2 or with methylamine (which primarily disrupts the thioester), the conformational changes detected by the mAb apparently occur after disruption of the thioester. Furthermore, the epitopes were also present on the corresponding C3 activation products. Immunoblotting experiments revealed that the epitopes for the three anti-C3d,g mAb were located on the C3d part, C-terminal to the thioester. The epitopes for 2 of the 3 anti-C3c mAb were located on the C-terminal alpha-chain fragment of C3c. Thus, this study provides immunochemical evidence for the biologic resemblance between C3(H2O) and C3 activation products. Implications of these findings for the activation process of C3 are discussed.

  1. 26 CFR 301.6501(n)-2 - Certain contributions to section 501(c)(3) organizations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... private foundation makes a contribution to a section 501(c)(3) organization as provided in section 4942(g)(3), and a deficiency of tax of such foundation occurs due to the failure of the section...

  2. 17 CFR 274.221 - Form N-23c-3, Notification of repurchase offer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... chapter). Editorial Note: For Federal Register citations affecting Form N-23c-3, see the List of CFR... COMMISSION (CONTINUED) FORMS PRESCRIBED UNDER THE INVESTMENT COMPANY ACT OF 1940 Forms for Other...

  3. C3 Vertebral Metastases From Tongue Adenoid Cystic Carcinoma: A Rare Case Report.

    PubMed

    Feng, Helin; Wang, Jin; Guo, Peng; Xu, Jianfa; Feng, Jiangang

    2015-07-01

    We report a rare case involving a patient with C3 vertebral body metastasis secondary to adenoid cystic carcinoma of the tongue.Five years after local resection of the primary tumor, magnetic resonance imaging showed a metastasis located in the left posterior border of the C3 vertebral body. Additionally, multiple pulmonary metastases were identified by computed tomography. Based on these findings, the patient underwent C2-3, C3-4 discectomy; C3 corpectomy; and titanium mesh fusion with a Zephir plate. The diagnosis was confirmed by the pathology findings. During 6 months of follow-up, the patient showed improvement and return of function of the cervical vertebrae, with no serious complications.Because of the scarcity of cases of vertebral metastases from tumors of the tongue in the literature, we have reported this case to add to the available evidence regarding this rarely encountered condition. PMID:26166118

  4. Artificial photosynthetic hydrogen evolution over g-C3N4 nanosheets coupled with cobaloxime.

    PubMed

    Cao, Shao-Wen; Liu, Xin-Feng; Yuan, Yu-Peng; Zhang, Zhen-Yi; Fang, Jun; Loo, Say Chye Joachim; Barber, James; Sum, Tze Chien; Xue, Can

    2013-11-14

    We report an economic and noble-metal-free artificial photosynthetic system, consisting of g-C3N4 as a photosensitizer and a photocatalyst, and cobaloxime as a co-catalyst, for H2 generation. This system allows for effective electron transfer from excited g-C3N4 to Co(III)(dmgH)2pyCl to generate reduced cobaloxime intermediate species for efficient H2 evolution. Transient fluorescence studies reveal that the presence of cobaloxime and TEOA promotes the population of excited electrons to transfer from g-C3N4, which is responsible for the high photocatalytic activity of this g-C3N4-cobaloxime conjugation system. PMID:24072333

  5. Novel function of complement C3d as an autologous helper T-cell target.

    PubMed

    Knopf, Paul M; Rivera, Daniel S; Hai, Si-Han; McMurry, Julie; Martin, William; De Groot, Anne S

    2008-01-01

    The C3d fragment of complement component C3 has been shown to enhance immune responses to antigens that lack T-cell epitopes such as bacterial polysaccharides. C3d binds to the B-cell complement receptor 2 (CR2 or CD21); this binding serves as a co-activation signal to the B cell when the polysaccharide antigen portion binds simultaneously to the B-cell receptor (surface Ig). Bringing together receptor-associated signal transduction molecules CD19 and Igalpha/beta, respectively, results in a lower threshold of activation. Paradoxically, C3d has also been shown to enhance antibody titers in the CD21 knockout (KO) mouse model as well as increase Th1 and Th2 cytokine secretion, suggesting that that an auxiliary CR2-independent pathway of immune activation may exist. We hypothesized that in addition to its molecular adjuvant property that enhances signal 1 during B-cell activation (co-signal 1), C3d also contains T-cell epitopes that are able to stimulate autoreactive C3d peptide-specific helper T cells which we term 'co-signal 2'. Using the EpiMatrix T-cell epitope-mapping algorithm, we identified 11 putative T-cell epitopes in C3d, a very high epitope density for a 302 amino-acid sequence. Eight of these epitope candidates were synthesized and shown to bind a variety of class II HLA-DR molecules of different haplotypes, and to stimulate C3d peptide-specific T cells to secrete pro-inflammatory cytokines in vitro. Further, we demonstrate a C3d-peptide specific increase in CD4(+) intracellular IFN-gamma(+) T cells in peripheral blood mononuclear cells (PBMCs) exposed to C3d peptides in vitro. We believe that the discovery of these autologous T cells autoreactive for C3d provides evidence supporting the 'co-signal 2' hypothesis and may offer a novel explanation of the CD21 KO paradox. PMID:18180801

  6. Regulation of C3 Activation by the Alternative Complement Pathway in the Mouse Retina

    PubMed Central

    Williams, Jennifer A. E.; Stampoulis, Dimitris; Gunter, Chloe E.; Greenwood, John; Adamson, Peter

    2016-01-01

    The purpose of this study was to examine the retinas of mice carrying hemizygous and null double deletions of Cfb-/- and Cfh-/-, and to compare these with the single knockouts of Cfb, Cfh and Cfd. Retinas were isolated from wild type (WT), Cfb-/-/Cfh-/-, Cfb-/-/Cfh+/-, Cfh-/-/Cfb+/-, Cfb-/-, Cfh-/- Cfd-/-, and Cfd+/- mice. Complement proteins were evaluated by western blotting, ELISA and immunocytochemistry, and retinal morphology was assessed using toluidine blue stained semi-thin sections. WT mice showed staining for C3 and its breakdown products in the retinal vasculature and the basal surface of the retinal pigment epithelium (RPE). Cfb-/- mice exhibited a similar C3 staining pattern to WT in the retinal vessels but a decrease in C3 and its breakdown products at the basal surface of the RPE. Deletion of both Cfb and Cfh restored C3 to levels similar to those observed in WT mice, however this reversal of phenotype was not observed in Cfh-/-/Cfb+/- or Cfb-/-/Cfh+/- mice. Loss of CFD caused an increase in C3 and a decrease in C3 breakdown products along the basal surface of the RPE. Overall the retinal morphology and retinal vasculature did not appear different across the various genotypes. We observed that C3 accumulates at the basal RPE in Cfb-/-, Cfb-/-/Cfh-/-, Cfb-/-/Cfh+/-, Cfd-/- and WT mice, but is absent in Cfh-/- and Cfh-/-/Cfb+/- mice, consistent with its consumption in the serum of mice lacking CFH when CFB is present. C3 breakdown products along the surface of the RPE were either decreased or absent when CFB, CFH or CFD was deleted or partially deleted. PMID:27564415

  7. FHR3 Blocks C3d-Mediated Coactivation of Human B Cells.

    PubMed

    Buhlmann, Denise; Eberhardt, Hannes U; Medyukhina, Anna; Prodinger, Wolfgang M; Figge, Marc Thilo; Zipfel, Peter F; Skerka, Christine

    2016-07-15

    The autoimmune renal disease deficient for complement factor H-related (CFHR) genes and autoantibody-positive form of hemolytic uremic syndrome is characterized by the presence of autoantibodies specific for the central complement regulator, factor H, combined with a homozygous deficiency, mostly in CFHR3 and CFHR1 Because FHR3 and FHR1 bind to C3d and inactivated C3b, which are ligands for complement receptor type 2 (CR2/CD21), the aim of the current study was to examine whether FHR3-C3d or FHR1-C3d complexes modulate B cell activation. Laser-scanning microscopy and automated image-based analysis showed that FHR3, but not FHR1 or factor H, blocked B cell activation by the BCR coreceptor complex (CD19/CD21/CD81). FHR3 bound to C3d, thereby inhibiting the interaction between C3d and CD21 and preventing colocalization of the coreceptor complex with the BCR. FHR3 neutralized the adjuvant effect of C3d on B cells, as shown by inhibited intracellular CD19 and Akt phosphorylation in Raji cells, as well as Ca(2+) release in peripheral B cells. In cases of CFHR3/CFHR1 deficiency, the FHR3 binding sites on C3d are occupied by factor H, which lacks B cell-inhibitory functions. These data provide evidence that FHR3, which is absent in patients with the autoimmune form of hemolytic uremic syndrome, is involved in B cell regulation. PMID:27279373

  8. Effect of Hypertriglyceridemia on Beta Cell Mass and Function in ApoC3 Transgenic Mice.

    PubMed

    Liu, Yun-Zi; Cheng, Xiaoyun; Zhang, Ting; Lee, Sojin; Yamauchi, Jun; Xiao, Xiangwei; Gittes, George; Qu, Shen; Jiang, Chun-Lei; Dong, H Henry

    2016-07-01

    Hypertriglyceridemia results from increased production and decreased clearance of triglyceride-rich very low-density lipoproteins, a pathological condition that accounts for heightened risk of ischemic vascular diseases in obesity and type 2 diabetes. Despite its intimate association with insulin resistance, whether hypertriglyceridemia constitutes an independent risk for beta cell dysfunction in diabetes is unknown. Answering this fundamental question is stymied by the fact that hypertriglyceridemia is intertwined with hyperglycemia and insulin resistance in obese and diabetic subjects. To circumvent this limitation, we took advantage of apolipoprotein C3 (ApoC3)-transgenic mice, a model with genetic predisposition to hypertriglyceridemia. We showed that ApoC3-transgenic mice, as opposed to age/sex-matched wild-type littermates, develop hypertriglyceridemia with concomitant elevations in plasma cholesterol and non-esterified fatty acid levels. Anti-insulin and anti-glucagon dual immunohistochemistry in combination with morphometric analysis revealed that ApoC3-transgenic and wild-type littermates had similar beta cell and alpha cell masses as well as islet size and architecture. These effects correlated with similar amplitudes of glucose-stimulated insulin secretion and similar degrees of postprandial glucose excursion in ApoC3-transgenic versus wild-type littermates. Oil Red O histology did not visualize lipid infiltration into islets, correlating with the lack of ectopic triglyceride and cholesterol depositions in the pancreata of ApoC3-transgenic versus wild-type littermates. ApoC3-transgenic mice, despite persistent hypertriglyceridemia, maintained euglycemia under both fed and fasting conditions without manifestation of insulin resistance and fasting hyperinsulinemia. Thus, hypertriglyceridemia per se is not an independent risk factor for beta cell dysfunction in ApoC3 transgenic mice. PMID:27226540

  9. A study of the C3H2 isomers and isotopologues: first interstellar detection of HDCCC

    NASA Astrophysics Data System (ADS)

    Spezzano, S.; Gupta, H.; Brünken, S.; Gottlieb, C. A.; Caselli, P.; Menten, K. M.; Müller, H. S. P.; Bizzocchi, L.; Schilke, P.; McCarthy, M. C.; Schlemmer, S.

    2016-02-01

    The partially deuterated linear isomer HDCCC of the ubiquitous cyclic carbene (c-C3H2) was observed in the starless cores TMC-1C and L1544 at 96.9 GHz, and a confirming line was observed in TMC-1 at 19.38 GHz. To aid the identification in these narrow line sources, four centimetre-wave rotational transitions (two in the previously reported Ka = 0 ladder and two new ones in the Ka = 1 ladder) and 23 transitions in the millimetre band between 96 and 272 GHz were measured in high-resolution laboratory spectra. Ten spectroscopic constants in a standard asymmetric top Hamiltonian allow the main transitions of astronomical interest in the Ka ≤ 3 rotational ladders to be calculated to within 0.1 km s-1 in radial velocity up to 400 GHz. Conclusive identification of the two astronomical lines of HDCCC was provided by the VLSR, which is the same as for the normal isotopic species (H2CCC) in the three narrow line sources. In these sources, deuterium fractionation in singly substituted H2CCC (HDCCC/H2CCC ~4-19%) is comparable to that in c-C3H2 (c-C3H2/c-C3HD ~5-17%) and similarly in doubly deuterated c-C3H2 (c-C3D2/c-C3HD ~3-17%), implying that the efficiency of the deuteration processes in the H2CCC and c-C3H2 isomers are comparable in dark clouds. Based on observations carried out with the IRAM 30 m Telescope. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain).

  10. Regulation of C3 Activation by the Alternative Complement Pathway in the Mouse Retina.

    PubMed

    Williams, Jennifer A E; Stampoulis, Dimitris; Gunter, Chloe E; Greenwood, John; Adamson, Peter; Moss, Stephen E

    2016-01-01

    The purpose of this study was to examine the retinas of mice carrying hemizygous and null double deletions of Cfb-/- and Cfh-/-, and to compare these with the single knockouts of Cfb, Cfh and Cfd. Retinas were isolated from wild type (WT), Cfb-/-/Cfh-/-, Cfb-/-/Cfh+/-, Cfh-/-/Cfb+/-, Cfb-/-, Cfh-/- Cfd-/-, and Cfd+/- mice. Complement proteins were evaluated by western blotting, ELISA and immunocytochemistry, and retinal morphology was assessed using toluidine blue stained semi-thin sections. WT mice showed staining for C3 and its breakdown products in the retinal vasculature and the basal surface of the retinal pigment epithelium (RPE). Cfb-/- mice exhibited a similar C3 staining pattern to WT in the retinal vessels but a decrease in C3 and its breakdown products at the basal surface of the RPE. Deletion of both Cfb and Cfh restored C3 to levels similar to those observed in WT mice, however this reversal of phenotype was not observed in Cfh-/-/Cfb+/- or Cfb-/-/Cfh+/- mice. Loss of CFD caused an increase in C3 and a decrease in C3 breakdown products along the basal surface of the RPE. Overall the retinal morphology and retinal vasculature did not appear different across the various genotypes. We observed that C3 accumulates at the basal RPE in Cfb-/-, Cfb-/-/Cfh-/-, Cfb-/-/Cfh+/-, Cfd-/- and WT mice, but is absent in Cfh-/- and Cfh-/-/Cfb+/- mice, consistent with its consumption in the serum of mice lacking CFH when CFB is present. C3 breakdown products along the surface of the RPE were either decreased or absent when CFB, CFH or CFD was deleted or partially deleted. PMID:27564415

  11. 17 CFR 270.6c-3 - Exemptions for certain registered variable life insurance separate accounts.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... account which meets the requirements of paragraph (a) of Rule 6e-2 (17 CFR 270.6e-2) or paragraph (a) of Rule 6e-3(T) (17 CFR 270.6e-3(T)) and registers as an investment company under section 8(a) of the Act... registered variable life insurance separate accounts. 270.6c-3 Section 270.6c-3 Commodity and...

  12. 17 CFR 270.6c-3 - Exemptions for certain registered variable life insurance separate accounts.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... account which meets the requirements of paragraph (a) of Rule 6e-2 (17 CFR 270.6e-2) or paragraph (a) of Rule 6e-3(T) (17 CFR 270.6e-3(T)) and registers as an investment company under section 8(a) of the Act... registered variable life insurance separate accounts. 270.6c-3 Section 270.6c-3 Commodity and...

  13. 17 CFR 270.6c-3 - Exemptions for certain registered variable life insurance separate accounts.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... account which meets the requirements of paragraph (a) of Rule 6e-2 (17 CFR 270.6e-2) or paragraph (a) of Rule 6e-3(T) (17 CFR 270.6e-3(T)) and registers as an investment company under section 8(a) of the Act... registered variable life insurance separate accounts. 270.6c-3 Section 270.6c-3 Commodity and...

  14. 17 CFR 270.6c-3 - Exemptions for certain registered variable life insurance separate accounts.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... account which meets the requirements of paragraph (a) of Rule 6e-2 (17 CFR 270.6e-2) or paragraph (a) of Rule 6e-3(T) (17 CFR 270.6e-3(T)) and registers as an investment company under section 8(a) of the Act... registered variable life insurance separate accounts. 270.6c-3 Section 270.6c-3 Commodity and...

  15. Theoretical microwave spectral constants for C3H/+/ and C4H/+/

    NASA Technical Reports Server (NTRS)

    Wilson, S.; Green, S.

    1980-01-01

    A number of linear conjugated carbon chain molecules have been observed in the interstellar gas. It has been suggested that ion molecule chemistry schemes may explain the formation of these compounds. In the present paper, theoretical bond lengths and rotation constants are obtained for C3H(+) and C4H(+). Calculations for C3 are used to assess the accuracy of the former. Recent results for C2H(+) are examined.

  16. Structure of Complement C3(H2O) Revealed By Quantitative Cross-Linking/Mass Spectrometry And Modeling*

    PubMed Central

    Pellarin, Riccardo; Sali, Andrej; Barlow, Paul N.

    2016-01-01

    The slow but spontaneous and ubiquitous formation of C3(H2O), the hydrolytic and conformationally rearranged product of C3, initiates antibody-independent activation of the complement system that is a key first line of antimicrobial defense. The structure of C3(H2O) has not been determined. Here we subjected C3(H2O) to quantitative cross-linking/mass spectrometry (QCLMS). This revealed details of the structural differences and similarities between C3(H2O) and C3, as well as between C3(H2O) and its pivotal proteolytic cleavage product, C3b, which shares functionally similarity with C3(H2O). Considered in combination with the crystal structures of C3 and C3b, the QCMLS data suggest that C3(H2O) generation is accompanied by the migration of the thioester-containing domain of C3 from one end of the molecule to the other. This creates a stable C3b-like platform able to bind the zymogen, factor B, or the regulator, factor H. Integration of available crystallographic and QCLMS data allowed the determination of a 3D model of the C3(H2O) domain architecture. The unique arrangement of domains thus observed in C3(H2O), which retains the anaphylatoxin domain (that is excised when C3 is enzymatically activated to C3b), can be used to rationalize observed differences between C3(H2O) and C3b in terms of complement activation and regulation. PMID:27250206

  17. 17 CFR 240.15c3-1a - Options (Appendix A to 17 CFR 240.15c3-1).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 4 2014-04-01 2014-04-01 false Options (Appendix A to 17 CFR... Options (Appendix A to 17 CFR 240.15c3-1). Link to an amendment published at 79 FR 1549, Jan. 8, 2014. (a... of the deductions specified in paragraphs (b)(1)(v)(C) or (b)(2) of this section. Theoretical...

  18. Complement C3dg-mediated erythrophagocytosis: implications for paroxysmal nocturnal hemoglobinuria

    PubMed Central

    Lin, Zhuoer; Schmidt, Christoph Q.; Koutsogiannaki, Sophia; Ricci, Patrizia; Risitano, Antonio M.; Lambris, John D.

    2015-01-01

    The clinical management of paroxysmal nocturnal hemoglobinuria (PNH), a rare but life-threatening hematologic disease, has fundamentally improved with the introduction of a therapeutic that prevents complement-mediated intravascular hemolysis. However, a considerable fraction of PNH patients show insufficient treatment response and remain transfusion dependent. Because the current treatment only prevents C5-induced lysis but not upstream C3 activation, it has been speculated that ongoing opsonization with C3 fragments leads to recognition and phagocytosis of PNH erythrocytes by immune cells. Here, for the first time, we provide experimental evidence for such extravascular hemolysis and demonstrate that PNH erythrocytes from anti–C5-treated patients are phagocytosed by activated monocytes in vitro. Importantly, we show that this uptake can be mediated by the end-stage opsonin C3dg, which is not traditionally considered a phagocytic marker, via interaction with complement receptor 3 (CR3). Interaction studies confirmed that C3dg itself can act as a ligand for the binding domain of CR3. The degree of C3dg-mediated erythrophagocytosis in samples from different PNH patients correlated well with the individual level of C3dg opsonization. This finding may guide future treatment options for PNH but also has potential implications for the description and management of other complement-mediated diseases. PMID:26082452

  19. AKR1C3 as a target in castrate resistant prostate cancer.

    PubMed

    Adeniji, Adegoke O; Chen, Mo; Penning, Trevor M

    2013-09-01

    Aberrant androgen receptor (AR) activation is the major driver of castrate resistant prostate cancer (CRPC). CRPC is ultimately fatal and more therapeutic agents are needed to treat this disease. Compounds that target the androgen axis by inhibiting androgen biosynthesis and or AR signaling are potential candidates for use in CRPC treatment and are currently being pursued aggressively. Aldo-keto reductase 1C3 (AKR1C3) plays a pivotal role in androgen biosynthesis within the prostate. It catalyzes the 17-ketoreduction of weak androgen precursors to give testosterone and 5α-dihydrotestosterone. AKR1C3 expression and activity has been implicated in the development of CRPC, making it a rational target. Selective inhibition of AKR1C3 will be important, however, due to the presence of closely related isoforms, AKR1C1 and AKR1C2 that are also involved in androgen inactivation. We examine the evidence that supports the vital role of AKR1C3 in CRPC and recent developments in the discovery of potent and selective AKR1C3 inhibitors. This article is part of a Special Issue entitled 'CSR 2013'.

  20. Boron doped g-C3N4 with enhanced photocatalytic UO22+ reduction performance

    NASA Astrophysics Data System (ADS)

    Lu, Changhai; Chen, Rongyue; Wu, Xi; Fan, Meifeng; Liu, Yunhai; Le, Zhanggao; Jiang, Shujuan; Song, Shaoqing

    2016-01-01

    Tuning the band gap and absorption intensity of visible-light by element doping is an attractive strategy to enhance the photocatalytic activity of semiconductor materials. Here we doped boron into g-C3N4 to construct highly efficient photocatalysts (B-g-C3N4) for the photocatalytic reduction of UO22+. Characterization and photocatalysis tests showed the band gap of B-g-C3N4 was narrowed, and the absorption intensity of visible-light was enhanced with increasing the formed N-B-C (BCN) of B-g-C3N4, which is consistent with the trend of the photocatalytic performance of B-g-C3N4. The optimized B-g-C3N4 photocatalyst with BCN content of 1.01 at.% exhibited excellent removal efficiency of UO22+ and good photocatalytic stability. Therefore, these results may lead to a new strategy for exploring the advanced photocatalysts based on the carbon nanomaterials with abundant BCN for the photocatalytic reduction of U(VI) pollutant.

  1. Structure of C3PO and mechanism of human RISC activation

    SciTech Connect

    Ye, Xuecheng; Huang, Nian; Liu, Ying; Paroo, Zain; Huerta, Carlos; Li, Peng; Chen, She; Liu, Qinghua; Zhang, Hong

    2011-08-26

    Assembly of the RNA-induced silencing complex (RISC) consists of loading duplex (guide-passenger) siRNA onto Argonaute (Ago2) and removing the passenger strand. Ago2 contributes critically to RISC activation by nicking the passenger strand. Here we reconstituted duplex siRNA-initiated RISC activity using recombinant human Ago2 (hAgo2) and C3PO, indicating that C3PO has a critical role in hAgo2-RISC activation. Consistently, genetic depletion of C3PO compromised RNA silencing in mammalian cells. We determined the crystal structure of hC3PO, which reveals an asymmetric octamer barrel consisting of six translin and two TRAX subunits. This asymmetric assembly is critical for the function of C3PO as an endonuclease that cleaves RNA at the interior surface. The current work supports a Dicer-independent mechanism for human RISC activation, in which Ago2 directly binds duplex siRNA and nicks the passenger strand, and then C3PO activates RISC by degrading the Ago2-nicked passenger strand.

  2. C3G regulates cortical neuron migration, preplate splitting and radial glial cell attachment.

    PubMed

    Voss, Anne K; Britto, Joanne M; Dixon, Mathew P; Sheikh, Bilal N; Collin, Caitlin; Tan, Seong-Seng; Thomas, Tim

    2008-06-01

    Neuronal migration is integral to the development of the cerebral cortex and higher brain function. Cortical neuron migration defects lead to mental disorders such as lissencephaly and epilepsy. Interaction of neurons with their extracellular environment regulates cortical neuron migration through cell surface receptors. However, it is unclear how the signals from extracellular matrix proteins are transduced intracellularly. We report here that mouse embryos lacking the Ras family guanine nucleotide exchange factor, C3G (Rapgef1, Grf2), exhibit a cortical neuron migration defect resulting in a failure to split the preplate into marginal zone and subplate and a failure to form a cortical plate. C3G-deficient cortical neurons fail to migrate. Instead, they arrest in a multipolar state and accumulate below the preplate. The basement membrane is disrupted and radial glial processes are disorganised and lack attachment in C3G-deficient brains. C3G is activated in response to reelin in cortical neurons, which, in turn, leads to activation of the small GTPase Rap1. In C3G-deficient cells, Rap1 GTP loading in response to reelin stimulation is reduced. In conclusion, the Ras family regulator C3G is essential for two aspects of cortex development, namely radial glial attachment and neuronal migration.

  3. AKR1C3 as a Target in Castrate Resistant Prostate Cancer

    PubMed Central

    Adeniji, Adegoke O.; Chen, Mo; Penning, Trevor M.

    2013-01-01

    Aberrant androgen receptor (AR) activation is the major driver of castrate resistant prostate cancer (CRPC). CRPC is ultimately fatal and more therapeutic agents are needed to treat this disease. Compounds that target the androgen axis by inhibiting androgen biosynthesis and or AR signaling are potential candidates for use in CRPC treatment and are currently being pursued aggressively. Aldo-keto reductase 1C3 (AKR1C3) plays a pivotal role in androgen biosynthesis within the prostate. It catalyzes the 17-ketoreduction of weak androgen precursors to give testosterone and 5α-dihydrotestosterone. AKR1C3 expression and activity has been implicated in the development of CRPC, making it a rational target. Selective inhibition of AKR1C3 will be important however, due to the presence of closely related isoforms, AKR1C1 and AKR1C2 that are also involved in androgen inactivation. We examine the evidence that supports the vital role of AKR1C3 in CRPC and recent developments in the discovery of potent and selective AKR1C3 inhibitors. PMID:23748150

  4. Spectroscopy and Photochemistry of Triplet 1,3-Dimethylpropynylidene (MeC3Me).

    PubMed

    Knezz, Stephanie N; Waltz, Terese A; Haenni, Benjamin C; Burrmann, Nicola J; McMahon, Robert J

    2016-09-28

    Photolysis (λ > 472 nm) of 2-diazo-3-pentyne (11) affords triplet 1,3-dimethylpropynylidene (MeC3Me, (3)3), which was characterized spectroscopically in cryogenic matrices. The infrared, electronic absorption, and electron paramagnetic resonance spectra of MeC3Me ((3)3) are compared with those of the parent system (HC3H) to ascertain the effect of alkyl substituents on delocalized carbon chains of this type. Quantum chemical calculations (CCSD(T)/ANO1) predict an unsymmetrical equilibrium structure for triplet MeC3Me ((3)3), but they also reveal a very shallow potential energy surface. The experimental IR spectrum of triplet MeC3Me ((3)3) is best interpreted in terms of a quasilinear, axially symmetric structure. EPR spectra yield zero-field splitting parameters that are typical for triplet carbenes with axial symmetry (|D/hc| = 0.63 cm(-1), |E/hc| = ∼ 0 cm(-1)), while theoretical analysis suggests that the methyl substituents confer significant spin polarization to the carbon chain. Upon irradiation into the near-UV electronic absorption (λmax 350 nm), MeC3Me ((3)3) undergoes 1,2-hydrogen migration to yield pent-1-en-3-yne (4), a photochemical reaction that is typical of carbenes bearing a methyl substituent. This facile process apparently precludes photoisomerization to other interesting C5H6 isomers, in contrast to the rich photochemistry of the parent C3H2 system.

  5. Thermomagnetic analysis of meteorites, 3. C3 and C4 chondrites

    USGS Publications Warehouse

    Herndon, J.M.; Rowe, M.W.; Larson, E.E.; Watson, D.E.

    1976-01-01

    Thermomagnetic analysis was made on samples of all known C3 and C4 chondrites in a controlled oxygen atmosphere. Considerable variation was noted in the occurrence of magnetic minerals, comparable to the variation observed earlier in the C2 chondrites. Magnetite was found as the only major magnetic phase in samples of only three C3 chondrites (2-4 wt.%) and the Karoonda C4 chondrite (7.7 wt.%). The magnetite content of these three C3 chondrites is only about one-third that observed in the C1 and C2 chondrites which were found to contain magnetite as the only magnetic phase. Five C3 chondrites were observed to undergo chemical change during heating, producing magnetite: this behavior is characteristic of troilite oxidation. Upper limits on initial magnetite content of about 1-9% were established for these meteorites. Samples of the remaining five C3 chondrites and the Coolidge C4 chondrite were found to contain both magnetite and metallic iron. In two samples, iron containing ???2% Ni was observed, while in the other four, the iron contained 6-8 wt.% Ni. In addition to containing both magnetite and iron metal, three of these samples reacted during heating to form additional magnetite. Variations in the magnetic mineralogy and, hence by inference bulk mineralogy, of C3 and C4 chondrites indicate a more complex genesis than is evident from whole-rock elemental abundance patterns. ?? 1976.

  6. Membranoproliferative glomerulonephritis with isolated C3 deposits: case report and literature review.

    PubMed

    Darouich, Sihem; Goucha, Rym; Jaafoura, Mohamed Habib; Zekri, Semy; Kheder, Adel; Ben Maiz, Hédi

    2011-02-01

    Membranoproliferative glomerulonephritis with isolated C3 deposits (MPGNC3) is an uncommon condition characterized by overt glomerular C3 deposits in the absence of immunoglobulins and intramembranous dense deposits. Here the authors describe the clinical and morphological features of primary MPGNC3 in a 13-year-old boy and critically review the previously published cases. The patient presented with nephrotic syndrome and microscopic hematuria. Blood tests revealed very low circulating C3 levels. The renal biopsy exhibited subendothelial, subepithelial, and mesangial deposits, with C3 but not immunoglobulins seen on immunofluorescence. This case and the review of the literature indicate that the serum complement profile with decreased levels of C3 and normal levels of classical pathway components together with glomerular deposits containing exclusively complement C3 is highly suggestive of alternative pathway activation. The diagnosis of acquired and/or genetic complement abnormalities in some cases supports that complement dysregulation is implicated in the pathogenesis of MPGNC3. Such data show great promise to provide new therapy strategies based on modulation of the complement system activity.

  7. Regulators of complement activity mediate inhibitory mechanisms through a common C3b-binding mode.

    PubMed

    Forneris, Federico; Wu, Jin; Xue, Xiaoguang; Ricklin, Daniel; Lin, Zhuoer; Sfyroera, Georgia; Tzekou, Apostolia; Volokhina, Elena; Granneman, Joke Cm; Hauhart, Richard; Bertram, Paula; Liszewski, M Kathryn; Atkinson, John P; Lambris, John D; Gros, Piet

    2016-05-17

    Regulators of complement activation (RCA) inhibit complement-induced immune responses on healthy host tissues. We present crystal structures of human RCA (MCP, DAF, and CR1) and a smallpox virus homolog (SPICE) bound to complement component C3b. Our structural data reveal that up to four consecutive homologous CCP domains (i-iv), responsible for inhibition, bind in the same orientation and extended arrangement at a shared binding platform on C3b. Large sequence variations in CCP domains explain the diverse C3b-binding patterns, with limited or no contribution of some individual domains, while all regulators show extensive contacts with C3b for the domains at the third site. A variation of ~100° rotation around the longitudinal axis is observed for domains binding at the fourth site on C3b, without affecting the overall binding mode. The data suggest a common evolutionary origin for both inhibitory mechanisms, called decay acceleration and cofactor activity, with variable C3b binding through domains at sites ii, iii, and iv, and provide a framework for understanding RCA disease-related mutations and immune evasion. PMID:27013439

  8. The g-C3 N4 /C2 N Nanocomposite: A g-C3 N4 -Based Water-Splitting Photocatalyst with Enhanced Energy Efficiency.

    PubMed

    Wang, Huimin; Li, Xingxing; Yang, Jinlong

    2016-07-01

    Water-splitting photocatalysts with good energy efficiency are highly desirable, among which metal-free graphitic carbon nitride (g-C3 N4 ) is considered to be very promising and has been intensively studied in recent years. However, its practical application is hindered by the relatively low efficiencies of visible-light absorption and electron-hole separation. Herein, based on first-principles calculations, it is predicted that, by forming nanocomposites with another carbon nitride (C2 N), the energy efficiency of g-C3 N4 can be significantly improved. On one hand, C2 N has a wide, strong optical absorption in the visible-light region, which acts as a photosensitizer and enhances the photoabsorption efficiency of the composite photocatalyst. On the other hand, C2 N forms a type II heterojunction with g-C3 N4 , which leads to efficient separation of photogenerated electron-hole pairs through the chemical potential difference between the two components. These results provide a potential route to achieve highly efficient metal-free photocatalysts for water splitting. PMID:27110945

  9. The g-C3 N4 /C2 N Nanocomposite: A g-C3 N4 -Based Water-Splitting Photocatalyst with Enhanced Energy Efficiency.

    PubMed

    Wang, Huimin; Li, Xingxing; Yang, Jinlong

    2016-07-01

    Water-splitting photocatalysts with good energy efficiency are highly desirable, among which metal-free graphitic carbon nitride (g-C3 N4 ) is considered to be very promising and has been intensively studied in recent years. However, its practical application is hindered by the relatively low efficiencies of visible-light absorption and electron-hole separation. Herein, based on first-principles calculations, it is predicted that, by forming nanocomposites with another carbon nitride (C2 N), the energy efficiency of g-C3 N4 can be significantly improved. On one hand, C2 N has a wide, strong optical absorption in the visible-light region, which acts as a photosensitizer and enhances the photoabsorption efficiency of the composite photocatalyst. On the other hand, C2 N forms a type II heterojunction with g-C3 N4 , which leads to efficient separation of photogenerated electron-hole pairs through the chemical potential difference between the two components. These results provide a potential route to achieve highly efficient metal-free photocatalysts for water splitting.

  10. Polymorphism of phosphoric oxide

    USGS Publications Warehouse

    Hill, W.L.; Faust, G.T.; Hendricks, S.B.

    1943-01-01

    The melting points and monotropic relationship of three crystalline forms of phosphoric oxide were determined by the method of quenching. Previous vapor pressure data are discussed and interpreted to establish a pressure-temperature diagram (70 to 600??) for the one-component system. The system involves three triple points, at which solid, liquid and vapor (P4O10) coexist in equilibrium, namely: 420?? and 360 cm., 562?? and 43.7 cm. and 580?? and 55.5 cm., corresponding to the hexagonal, orthorhombic and stable polymorphs, respectively, and at least two distinct liquids, one a stable polymer of the other, which are identified with the melting of the stable form and the hexagonal modification, respectively. Indices of refraction of the polymorphs and glasses were determined. The density and the thermal, hygroscopic and structural properties of the several phases are discussed.

  11. [Polymorphs of clopidogrel bisulfate].

    PubMed

    Liu, Yi; Huang, Hai-Wei; Wu, Jian-Min; Shi, Ya-Qin; Yang, La-Hu

    2013-08-01

    This paper is to report the polymorphism of raw materials of clopidogrel bisulfate at home and abroad. By the analysis of Fourier transform infrared spectroscopy (FTIR) and powder X-ray diffraction (p-XRD), samples are roughly classified into two groups, except one patent material. And the differential scanning calorimeter (DSC) examination showed more detailed information for these materials. The results of the study could provide comprehensive basis for the quality evaluation of clopidogrel bisulfate. PMID:24187849

  12. Experimental and theoretical study on the thermal decomposition of C3H6 (propene).

    PubMed

    Hung, Wei-Chung; Tsai, Chieh-Ying; Matsui, Hiroyuki; Wang, Niann-Shiah; Miyoshi, Akira

    2015-02-26

    The mechanism of the thermal unimolecular decomposition of C3H6 (propene) is studied both theoretically and experimentally. The potential energy surfaces for possible reaction pathways are investigated by CBS-QB3 level of quantum chemical calculations, and RRKM/master-equation calculation is performed for the main channels. The time evolutions of H atoms are observed experimentally by using a highly sensitive detection technique (ARAS, detection limit ≈ 10(11) atoms cm(-3)) behind reflected shock waves (0.5-1.0 ppm C3H6 diluted in Ar, 1450-1710 K at 2.0 atm). The objective of this study is to examine the main product channels by combining the experimental and theoretical investigations on the yield and the rates of H atom production. Present quantum chemical calculations identify reactions (1a-1d) as the candidates of product channels: C3H6 → aC3H5 (allyl radical) + H (1a), C3H6 → CH3 + C2H3 (vinyl radical) (1b), C3H6 → CH4 + :CCH2 (singlet vinyldene radical) (1c), and C3H6 → C3H4 (allene) + H2 (1d). The RRKM calculations reveal the branching fractions for (1a), (1b), and (1c) to be approximately 0.8, 0.2, and 0.01, respectively. Reaction (1d) and other product channels are negligible (< 0.1 %), and the pressure dependence of the branching fraction is small under the present experimental conditions. The experimental yield of H atoms (1.7-2.0) is consistent with the theoretical branching fractions considering the H-atom production from the rapid subsequent thermal decomposition of a C3H5 and C2H3. From the observed time profiles of H atoms, the rate of overall thermal decomposition of C3H6 can be evaluated as Ln(k1/s(-1)) = (38.05 ± 1.18) - (48.91 ± 1.85) × 10(3) K/T, which is in excellent agreement with the theoretical prediction.

  13. Functions of the complement components C3 and C5 during sepsis

    PubMed Central

    Flierl, Michael A.; Rittirsch, Daniel; Nadeau, Brian A.; Day, Danielle E.; Zetoune, Firas S.; Sarma, J. Vidya; Huber-Lang, Markus S.; Ward, Peter A.

    2008-01-01

    Activation of the complement system is a key event in the pathogenesis of sepsis. Nevertheless, the exact mechanisms remain inadequately understood. In the current study, we examined the role of complement C3 and C5 in sepsis in wild-type and C3- or C5-deficient mice induced by cecal ligation and puncture. When compared to wild-type mice, C5−/− showed identical survival, and C3−/− presented significantly reduced survival. Interestingly, this was associated with significant decreases in plasma levels of proinflammatory mediators. Moreover, although septic C3−/− animals displayed a 10-fold increase of blood-borne bacteria, C5−/− animals exhibited a 400-fold increase in bacteremia when compared to wild-type mice. These effects were linked to the inability of C5−/− mice to assemble the terminal membrane attack complex (MAC), as determined by complement hemolytic activity (CH-50). Surprisingly, although negative control C3−/− mice failed to generate the MAC, significant increases of MAC formation was found in septic C3−/− mice. In conclusion, our data corroborate that hemolytic complement activity is essential for control of bacteremia in septic mice. Thus, during sepsis, blockade of C5a or its receptors (rather than C5) seems a more promising strategy, because C5a-blockade still allows for MAC formation while the adverse effects of C5a are prevented.—Flierl, M. A., Rittirsch, D., Nadeau, B. A., Day, D. E., Zetoune, F. S., Sarma, J. V., Huber-Lang, M. S., Ward, P. A. Functions of the complement components C3 and C5 during sepsis. PMID:18587006

  14. The chemistry of C3 and C2 in cometary comae. I. Current models revisited

    NASA Astrophysics Data System (ADS)

    Weiler, M.

    2012-02-01

    Context. It is widely accepted that C3 and in particular C2 play an important role in the compositional classification of comets, and the most well-established classification scheme to date is indeed based on the Haser production rates of these two radicals. A link between both C3 and C2 and their actual parent molecules would therefore be desirable to allow both a physical and chemical interpretation of the compositional classification of comets. A first detailed study was performed by Helbert and collaborators for comet C/1995 O1 (Hale-Bopp), which suggested a link between these two radicals and the parent species C2H2, C2H6, and C3H4. Aims: We extend previous studies of the formation of C3 and C2 to other comets at smaller heliocentric distances. The proposed model for the formation of these two radicals is tested for these comets. Methods: We compare the observed radial column densities of C3 and C2 in the comae of the comets C/2001 Q4 (NEAT), C/2002 T7 (LINEAR), and 9P/Tempel 1 with the results of a one-dimensional multi-fluid coma chemistry model. The shape of the modelled radial column density profiles are compared with the observed profiles, and the production rates of the parent species are computed by fitting the observational data with the model. Results: We do not find that C2H6 is a significant parent species of the observed cometary C2. Furthermore, electron impact reactions do not play an important role in the formation of C3. The model for the formation of C3 and C2 derived from comet Hale-Bopp is inconsistent with observations of these radicals in other comets. Based on observations collected at the European Southern Observatory, Chile (ESO programmes 073.C-0571 and 075.C-0355).

  15. Molecular recognition of an ADP-ribosylating Clostridium botulinum C3 exoenzyme by RalA GTPase

    PubMed Central

    Holbourn, Kenneth P.; Sutton, J. Mark; Evans, Hazel R.; Shone, Clifford C.; Acharya, K. Ravi

    2005-01-01

    C3 exoenzymes (members of the ADP-ribosyltranferase family) are produced by Clostridium botulinum (C3bot1 and -2), Clostridium limosum (C3lim), Bacillus cereus (C3cer), and Staphylococcus aureus (C3stau1–3). These exoenzymes lack a translocation domain but are known to specifically inactivate Rho GTPases in host target cells. Here, we report the crystal structure of C3bot1 in complex with RalA (a GTPase of the Ras subfamily) and GDP at a resolution of 2.66 Å. RalA is not ADP-ribosylated by C3 exoenzymes but inhibits ADP-ribosylation of RhoA by C3bot1, C3lim, and C3cer to different extents. The structure provides an insight into the molecular interactions between C3bot1 and RalA involving the catalytic ADP-ribosylating turn–turn (ARTT) loop from C3bot1 and helix α4 and strand β6 (which are not part of the GDP-binding pocket) from RalA. The structure also suggests a molecular explanation for the different levels of C3-exoenzyme inhibition by RalA and why RhoA does not bind C3bot1 in this manner. PMID:15809419

  16. "Invar"-like behavior in compressed Fe7C3 with implication for deep carbon cycle

    NASA Astrophysics Data System (ADS)

    Liu, J.; Li, J.; Ikuta, D.

    2014-12-01

    Iron carbide Fe7C3 has recently emerged as a leading candidate component of the inner core because it is likely the first phase to solidify from a liquid containing iron and a small amount of carbon, and previous studies suggest that it provides a good match for the density of the inner core under relevant conditions. Pressure-induced magnetic transitions have been observed in Fe7C3 (Chen et al., 2012). The pressure of the ferromagnetic to paramagnetic transition remains controversial and its effect on equation of state (EoS) is unclear, thus introducing uncertainties in estimating the density of Fe7C3 under inner core pressures. Here we report the lattice parameters and unit cell volume of hexagonal Fe7C3 at 300 K and up to 70 GPa, obtained through synchrotron x-ray diffraction measurements using a diamond anvil cell. The experiments used fine powder of Fe7C3 that was synthesized in the multi-anvil apparatus at the University of Michigan. The sample was embedded in neon pressure medium together with Au powder and ruby spheres as additional pressure markers. We observed significant softening at 5~8 GPa, similar to the reported "invar"-like behavior in Fe-Ni alloy (Dubrovinsky et al., 2001). For comparison, the compression curve of iron in the same loading turned out to be smooth as expected, which confirms that the abnormal behavior in Fe7C3 compression curve is due to its own property change and not an artifact. The new data allow us to establish the equation-of-state (EoS) of Fe7C3 and then estimate the density of Fe7C3 at inner core conditions. References: Chen, B., Gao, L.L., Lavina, B., Dera, P., Alp, E.E., Zhao, J.Y., Li, J., 2012. Magneto-elastic coupling in compressed Fe7C3 supports carbon in Earth's inner core. Geophys Res Lett 39. Dubrovinsky, L., Dubrovinskaia, N., Abrikosov, I.A., Vennstrom, M., Westman, F., Carlson, S., van Schilfgaarde, M., Johansson, B., 2001. Pressure-induced invar effect in Fe-Ni alloys. Phys Rev Lett 86, 4851-4854.

  17. An extended mini-complement factor H molecule ameliorates experimental C3 glomerulopathy

    PubMed Central

    Nichols, Eva-Maria; Barbour, Thomas D; Pappworth, Isabel Y; Wong, Edwin K S; Palmer, Jeremy M; Sheerin, Neil S; Pickering, Matthew C; Marchbank, Kevin J

    2015-01-01

    Abnormal regulation of the complement alternative pathway is associated with C3 glomerulopathy. Complement factor H is the main plasma regulator of the alternative pathway and consists of 20 short consensus repeat (SCR) domains. Although recombinant full-length factor H represents a logical treatment for C3 glomerulopathy, its production has proved challenging. We and others have designed recombinant mini-factor H proteins in which ‘non-essential' SCR domains have been removed. Here, we report the in vitro and in vivo effects of a mini-complement factor H protein, FH1–5^18–20, using the unique factor H–deficient (Cfh−/−) mouse model of C3 glomerulopathy. FH1–5^18–20 is comprised of the key complement regulatory domains (SCRs 1–5) linked to the surface recognition domains (SCRs 18–20). Intraperitoneal injection of FH1–5^18–20 in Cfh−/− mice reduced abnormal glomerular C3 deposition, similar to full-length factor H. Systemic effects on plasma alternative pathway control were comparatively modest, in association with a short half-life. Thus, FH1–5^18–20 is a potential therapeutic agent for C3 glomerulopathy and other renal conditions with alternative pathway-mediated tissue injury. PMID:26221753

  18. Is C4 photosynthesis less phenotypically plastic than C3 photosynthesis?

    PubMed

    Sage, Rowan F; McKown, Athena D

    2006-01-01

    C4 photosynthesis is a complex specialization that enhances carbon gain in hot, often arid habitats where photorespiration rates can be high. Certain features unique to C4 photosynthesis may reduce the potential for phenotypic plasticity and photosynthetic acclimation to environmental change relative to what is possible with C3 photosynthesis. During acclimation, the structural and physiological integrity of the mesophyll-bundle sheath (M-BS) complex has to be maintained if C4 photosynthesis is to function efficiently in the new environment. Disruption of the M-BS structure could interfere with metabolic co-ordination between the C3 and C4 cycles, decrease metabolite flow rate between the tissues, increase CO2 leakage from the bundle sheath, and slow enzyme activity. C4 plants have substantial acclimation potential, but in most cases lag behind the acclimation responses in C3 plants. For example, some C4 species are unable to maintain high quantum yields when grown in low-light conditions. Others fail to reduce carboxylase content in shade, leaving substantial over-capacity of Rubisco and PEP carboxylase in place. Shade-tolerant C4 grasses lack the capacity for maintaining a high state of photosynthetic induction following sunflecks, and thus may be poorly suited to exploit subsequent sunflecks compared with C3 species. In total, the evidence indicates that C4 photosynthesis is less phenotypically plastic than C3 photosynthesis, and this may contribute to the more restricted ecological and geographical distribution of C4 plants across the Earth.

  19. Vertical Distribution of C3-hydrocarbons in the Stratosphere of Titan

    NASA Astrophysics Data System (ADS)

    Li, Cheng; Zhang, Xi; Gao, Peter; Yung, Yuk

    2015-04-01

    Motivated by the recent detection of propene (C3H6) in the atmosphere of Titan, we use a one-dimensional Titan photochemical model with an updated eddy diffusion profile to systematically study the vertical profiles of the stable species in the C3-hydrocarbon family. We find that the stratospheric volume mixing ratio of propene (C3H6) peaks at 150 km with a value of 5 × 10-9, which is in good agreement with recent observations by the Composite Infrared Spectrometer on the Cassini spacecraft. Another important species that is currently missing from the hydrocarbon family in Titan's stratosphere is allene (CH2CCH2), an isomer of methylacetylene (CH3C2H). We predict that its mixing ratio in the stratosphere is about 10-9, which is on the margin of the detection limit. CH2CCH2 and CH3C2H equilibrate at a constant ratio in the stratosphere by hydrogen-exchanging reactions. Thus, by precisely measuring the ratio of CH2CCH2 to CH3C2H, the abundance of atomic hydrogen in the atmosphere can be inferred. No direct yield for the production of cyclopropane (c-C3H6) is available. From the discharge experiments of Navarro-González & Ramírez, the abundance of cyclopropane is estimated to be 100 times less than that of C3H6.

  20. In Silico Studies of C3 Metabolic Pathway Proteins of Wheat (Triticum aestivum)

    PubMed Central

    Naeem, Muhammad Kashif; Rauf, Sobiah; Iqbal, Hina; Nawaz Shah, Muhammad Kausar; Mir, Asif

    2013-01-01

    Photosynthesis is essential for plant productivity and critical for plant growth. More than 90% of plants have a C3 metabolic pathway primarily for carbon assimilation. Improving crop yields for food and fuel is a major challenge for plant biology. To enhance the production of wheat there is need to adopt the strategies that can create the change in plants at the molecular level. During the study we have employed computational bioinformatics and interactomics analysis of C3 metabolic pathway proteins in wheat. The three-dimensional protein modeling provided insight into molecular mechanism and enhanced understanding of physiological processes and biological systems. Therefore in our study, initially we constructed models for nine proteins involving C3 metabolic pathway, as these are not determined through wet lab experiment (NMR, X-ray Crystallography) and not available in RCSB Protein Data Bank and UniProt KB. On the basis of docking interaction analysis, we proposed the schematic diagram of C3 metabolic pathway. Accordingly, there also exist vice versa interactions between 3PGK and Rbcl. Future site and directed mutagenesis experiments in C3 plants could be designed on the basis of our findings to confirm the predicted protein interactions. PMID:23484105

  1. Physiological and growth responses of C3 and C4 plants at the Pleistocene glacial maximum

    SciTech Connect

    Strain, B.R.

    1995-06-01

    A C3 plant (Abutilon theophrasti) and a C4 plant (Amaranthus retroflexus) were grown from seed in the Duke University Phytotron under four CO2 concentrations (15 Pa, below the Pleistocene minimum), 27 Pa (pre-industrial), 35 Pa (current), and 70 Pa (future) to examine photosynthetic, growth and reproduction responses of annual plants to historic and future levels of CO2. Net photosynthesis and growth were greatly inhibited at 15 Pa and greatly stimulated at 70 Pa. in the C3 Abutilon but only slightly affected in the C4 Amaranthus. Flower bud initiation was not affected by CO2 treatment in either species but all flower buds in 15 Pa CO2 aborted in the C3 within two days of appearance while no inhibition of reproduction was observed at low CO2 in the C4. Differences in physiology, growth and reproduction to the low levels of atmospheric CO2 of the Pleistocene suggest that competitive interactions of C3 and C4 annuals have changed through geologic time. A major question concerning the survival and evolution of obligate C3 annuals during the CO2 minima of the Pleistocene is raised by the results of this study.

  2. Enhancing C3 photosynthesis: an outlook on feasible interventions for crop improvement.

    PubMed

    Singh, Jitender; Pandey, Prachi; James, Donald; Chandrasekhar, Kottakota; Achary, V Mohan Murali; Kaul, Tanushri; Tripathy, Baishnab C; Reddy, Malireddy K

    2014-12-01

    Despite the declarations and collective measures taken to eradicate hunger at World Food Summits, food security remains one of the biggest issues that we are faced with. The current scenario could worsen due to the alarming increase in world population, further compounded by adverse climatic conditions, such as increase in atmospheric temperature, unforeseen droughts and decreasing soil moisture, which will decrease crop yield even further. Furthermore, the projected increase in yields of C3 crops as a result of increasing atmospheric CO2 concentrations is much less than anticipated. Thus, there is an urgent need to increase crop productivity beyond existing yield potentials to address the challenge of food security. One of the domains of plant biology that promises hope in overcoming this problem is study of C3 photosynthesis. In this review, we have examined the potential bottlenecks of C3 photosynthesis and the strategies undertaken to overcome them. The targets considered for possible intervention include RuBisCO, RuBisCO activase, Calvin-Benson-Bassham cycle enzymes, CO2 and carbohydrate transport, and light reactions among many others. In addition, other areas which promise scope for improvement of C3 photosynthesis, such as mining natural genetic variations, mathematical modelling for identifying new targets, installing efficient carbon fixation and carbon concentrating mechanisms have been touched upon. Briefly, this review intends to shed light on the recent advances in enhancing C3 photosynthesis for crop improvement. PMID:25196090

  3. A previously unrecognized role of C3a in proteinuric progressive nephropathy.

    PubMed

    Morigi, Marina; Locatelli, Monica; Rota, Cinzia; Buelli, Simona; Corna, Daniela; Rizzo, Paola; Abbate, Mauro; Conti, Debora; Perico, Luca; Longaretti, Lorena; Benigni, Ariela; Zoja, Carlamaria; Remuzzi, Giuseppe

    2016-01-01

    Podocyte loss is the initial event in the development of glomerulosclerosis, the structural hallmark of progressive proteinuric nephropathies. Understanding mechanisms underlying glomerular injury is the key challenge for identifying novel therapeutic targets. In mice with protein-overload induced by bovine serum albumin (BSA), we evaluated whether the alternative pathway (AP) of complement mediated podocyte depletion and podocyte-dependent parietal epithelial cell (PEC) activation causing glomerulosclerosis. Factor H (Cfh(-/-)) or factor B-deficient mice were studied in comparison with wild-type (WT) littermates. WT+BSA mice showed podocyte depletion accompanied by glomerular complement C3 and C3a deposits, PEC migration to capillary tuft, proliferation, and glomerulosclerosis. These changes were more prominent in Cfh(-/-) +BSA mice. The pathogenic role of AP was documented by data that factor B deficiency preserved glomerular integrity. In protein-overload mice, PEC dysregulation was associated with upregulation of CXCR4 and GDNF/c-Ret axis. In vitro studies provided additional evidence of a direct action of C3a on proliferation and CXCR4-related migration of PECs. These effects were enhanced by podocyte-derived GDNF. In patients with proteinuric nephropathy, glomerular C3/C3a paralleled PEC activation, CXCR4 and GDNF upregulation. These results indicate that mechanistically uncontrolled AP complement activation is not dispensable for podocyte-dependent PEC activation resulting in glomerulosclerosis. PMID:27345360

  4. P7C3 neuroprotective chemicals block axonal degeneration and preserve function after traumatic brain injury.

    PubMed

    Yin, Terry C; Britt, Jeremiah K; De Jesús-Cortés, Héctor; Lu, Yuan; Genova, Rachel M; Khan, Michael Z; Voorhees, Jaymie R; Shao, Jianqiang; Katzman, Aaron C; Huntington, Paula J; Wassink, Cassie; McDaniel, Latisha; Newell, Elizabeth A; Dutca, Laura M; Naidoo, Jacinth; Cui, Huxing; Bassuk, Alexander G; Harper, Matthew M; McKnight, Steven L; Ready, Joseph M; Pieper, Andrew A

    2014-09-25

    The P7C3 class of neuroprotective aminopropyl carbazoles has been shown to block neuronal cell death in models of neurodegeneration. We now show that P7C3 molecules additionally preserve axonal integrity after injury, before neuronal cell death occurs, in a rodent model of blast-mediated traumatic brain injury (TBI). This protective quality may be linked to the ability of P7C3 molecules to activate nicotinamide phosphoribosyltransferase, the rate-limiting enzyme in nicotinamide adenine dinucleotide salvage. Initiation of daily treatment with our recently reported lead agent, P7C3-S243, 1 day after blast-mediated TBI blocks axonal degeneration and preserves normal synaptic activity, learning and memory, and motor coordination in mice. We additionally report persistent neurologic deficits and acquisition of an anxiety-like phenotype in untreated animals 8 months after blast exposure. Optimized variants of P7C3 thus offer hope for identifying neuroprotective agents for conditions involving axonal damage, neuronal cell death, or both, such as occurs in TBI. PMID:25220467

  5. P7C3 and an unbiased approach to drug discovery for neurodegenerative diseases

    PubMed Central

    McKnight, Steven L.; Ready, Joseph M.

    2014-01-01

    A novel neuroprotective small molecule was discovered using a target-agnostic in vivo screen in living mice. This aminopropyl carbazole, named P7C3, is orally bioavailable, crosses the blood–brain barrier, and is non-toxic at doses several fold higher than the efficacious dose. The potency and drug-like properties of P7C3 were optimized through a medicinal chemistry campaign, providing analogues for detailed examination. Improved versions, such as (−)-P7C3-S243 and P7C3-A20, displayed neuro-protective properties in rodent models of Parkinson’s disease, amyotrophic lateral sclerosis, traumatic brain injury and age-related cognitive decline. Derivatives appended with immobilizing moieties may reveal the protein targets of the P7C3 class of neuroprotective compounds. Our results indicate that unbiased, in vivo screens might provide starting points for the development of treatments for neurodegenerative diseases as well as tools to study the biology underlying these disorders. PMID:24514864

  6. Ti-decorated graphitic-C3N4 monolayer: A promising material for hydrogen storage

    NASA Astrophysics Data System (ADS)

    Zhang, Weibin; Zhang, Zhijun; Zhang, Fuchun; Yang, Woochul

    2016-11-01

    Ti-decorated graphitic carbon nitride (g-C3N4) monolayer as a promising material system for high-capacity hydrogen storage is proposed through density functional theory calculations. The stability and hydrogen adsorption of Ti-decorated g-C3N4 is analyzed by computing the adsorption energy, the charge population, and electronic density of states. The most stable decoration site of Ti atom is the triangular N hole in g-C3N4 with an adsorption energy of -7.58 eV. The large diffusion energy barrier of the adsorbed Ti atom of ∼6.00 eV prohibits the cluster formation of Ti atoms. The electric field induced by electron redistribution of Ti-adsorbed porous g-C3N4 significantly enhanced hydrogen adsorption up to five H2 molecules at each Ti atom with an average adsorption energy of -0.30 eV/H2. The corresponding hydrogen capacity reaches up to 9.70 wt% at 0 K. In addition, the hydrogen capacity is predicted to be 6.30 wt% at 233 K and all adsorbed H2 are released at 393 K according to molecular dynamics simulation. Thus, the Ti-decorated g-C3N4 monolayer is suggested to be a promising material for hydrogen storage suggested by the DOE for commercial applications.

  7. Preliminary Mission Results and Project Evaluation of the Delfi-C3 Nano-satellite

    NASA Astrophysics Data System (ADS)

    Bouwmeester, J.; Aalbers, G. T.; Ubbels, W. J.

    2008-08-01

    This paper discusses preliminary mission results of Delfi-C3 up till the early operations phase. The first section will discuss the design philosophy of Delfi-C3. To reduce operational risks, Delfi-C3 followed the KISS principle and is designed to be Single-Point-of-Failure- free. A balance is made between adoption of professional space engineering customs and standards on one hand and the limitations of small satellites, financial budgets and limited human resources on the other hand. The second section of the paper discusses the project planning and management of Delfi-C3. Addressed are reasonable timelines for the development of a nano-satellite, how to deal with a launch slip and the occasional conflicts between the interest of the students and the interest of the project. The third section of the paper will present the results of the early operations of Delfi-C3. Discussed are the performance of the payloads, the bus and the ground network of the satellite. Finally, an early statement of the mission success will be given.

  8. A previously unrecognized role of C3a in proteinuric progressive nephropathy

    PubMed Central

    Morigi, Marina; Locatelli, Monica; Rota, Cinzia; Buelli, Simona; Corna, Daniela; Rizzo, Paola; Abbate, Mauro; Conti, Debora; Perico, Luca; Longaretti, Lorena; Benigni, Ariela; Zoja, Carlamaria; Remuzzi, Giuseppe

    2016-01-01

    Podocyte loss is the initial event in the development of glomerulosclerosis, the structural hallmark of progressive proteinuric nephropathies. Understanding mechanisms underlying glomerular injury is the key challenge for identifying novel therapeutic targets. In mice with protein-overload induced by bovine serum albumin (BSA), we evaluated whether the alternative pathway (AP) of complement mediated podocyte depletion and podocyte-dependent parietal epithelial cell (PEC) activation causing glomerulosclerosis. Factor H (Cfh−/−) or factor B-deficient mice were studied in comparison with wild-type (WT) littermates. WT+BSA mice showed podocyte depletion accompanied by glomerular complement C3 and C3a deposits, PEC migration to capillary tuft, proliferation, and glomerulosclerosis. These changes were more prominent in Cfh−/− +BSA mice. The pathogenic role of AP was documented by data that factor B deficiency preserved glomerular integrity. In protein-overload mice, PEC dysregulation was associated with upregulation of CXCR4 and GDNF/c-Ret axis. In vitro studies provided additional evidence of a direct action of C3a on proliferation and CXCR4-related migration of PECs. These effects were enhanced by podocyte-derived GDNF. In patients with proteinuric nephropathy, glomerular C3/C3a paralleled PEC activation, CXCR4 and GDNF upregulation. These results indicate that mechanistically uncontrolled AP complement activation is not dispensable for podocyte-dependent PEC activation resulting in glomerulosclerosis. PMID:27345360

  9. Enhancing C3 photosynthesis: an outlook on feasible interventions for crop improvement.

    PubMed

    Singh, Jitender; Pandey, Prachi; James, Donald; Chandrasekhar, Kottakota; Achary, V Mohan Murali; Kaul, Tanushri; Tripathy, Baishnab C; Reddy, Malireddy K

    2014-12-01

    Despite the declarations and collective measures taken to eradicate hunger at World Food Summits, food security remains one of the biggest issues that we are faced with. The current scenario could worsen due to the alarming increase in world population, further compounded by adverse climatic conditions, such as increase in atmospheric temperature, unforeseen droughts and decreasing soil moisture, which will decrease crop yield even further. Furthermore, the projected increase in yields of C3 crops as a result of increasing atmospheric CO2 concentrations is much less than anticipated. Thus, there is an urgent need to increase crop productivity beyond existing yield potentials to address the challenge of food security. One of the domains of plant biology that promises hope in overcoming this problem is study of C3 photosynthesis. In this review, we have examined the potential bottlenecks of C3 photosynthesis and the strategies undertaken to overcome them. The targets considered for possible intervention include RuBisCO, RuBisCO activase, Calvin-Benson-Bassham cycle enzymes, CO2 and carbohydrate transport, and light reactions among many others. In addition, other areas which promise scope for improvement of C3 photosynthesis, such as mining natural genetic variations, mathematical modelling for identifying new targets, installing efficient carbon fixation and carbon concentrating mechanisms have been touched upon. Briefly, this review intends to shed light on the recent advances in enhancing C3 photosynthesis for crop improvement.

  10. Structure, electronic, mechanical and optical properties of ternary YAl3C3 carbide

    NASA Astrophysics Data System (ADS)

    Hussain, Altaf; Javed, Athar; Mehmood, Salman; Rasool, M. Nasir; Khan, Muhammad Azhar; Iqbal, Faisal

    2016-05-01

    The electronic structure, mechanical and optical properties of ternary yttrium aluminum carbide (YAl3C3) has been studied by first principles approach. The crystal structure and elastic properties are studied by using Vienna ab initio simulation package (VASP). An orthogonalized linear combination of atomic orbitals (OLCAO) method based on the density functional theory (DFT) is implemented to elucidate the electronic structure and optical properties of ternary YAl3C3 carbide. The YAl3C3 carbide exhibits a narrow indirect band gap, Eg=0.12 eV which shows its poor metallic and/or semiconductor behavior. The effective charge (Q*) calculation reveals more charge transfer from Al-sites as compared to Y-sites which indicates dominant ionic character of Al-sites. The analysis of structure and bond order (BO) calculations show that the Al-C bonds in the basal plane are much stronger as compared to Al-C bonds along the c-axis. The Al-C bonds lying in the basal plane have main contribution into the overall stiffness of YAl3C3 carbide. The effective mass of charge carriers (electrons and holes) and inter-band optical properties (complex dielectric function and optical conductivity) are also studied which show high degree of anisotropy in YAl3C3.

  11. Nanoscale charge transport in cytochrome c3/DNA network: Comparative studies between redox-active molecules

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Harumasa; Che, Dock-Chil; Hirano, Yoshiaki; Suzuki, Masayuki; Higuchi, Yoshiki; Matsumoto, Takuya

    2015-09-01

    The redox-active molecule of a cytochrome c3/DNA network exhibits nonlinear current-voltage (I-V) characteristics with a threshold bias voltage at low temperature and zero-bias conductance at room temperature. I-V curves for the cytochrome c3/DNA network are well matched with the Coulomb blockade network model. Comparative studies of the Mn12 cluster, cytochrome c, and cytochrome c3, which have a wide variety of redox potentials, indicate no difference in charge transport, which suggests that the conduction mechanism is not directly related to the redox states. The charge transport mechanism has been discussed in terms of the newly-formed electronic energy states near the Fermi level, induced by the ionic interaction between redox-active molecules with the DNA network.

  12. Structure of complement receptor 2 in complex with its C3d ligand.

    PubMed

    Szakonyi, G; Guthridge, J M; Li, D; Young, K; Holers, V M; Chen, X S

    2001-06-01

    Complement receptor 2 (CR2/CD21) is an important receptor that amplifies B lymphocyte activation by bridging the innate and adaptive immune systems. CR2 ligands include complement C3d and Epstein-Barr virus glycoprotein 350/220. We describe the x-ray structure of this CR2 domain in complex with C3d at 2.0 angstroms. The structure reveals extensive main chain interactions between C3d and only one short consensus repeat (SCR) of CR2 and substantial SCR side-side packing. These results provide a detailed understanding of receptor-ligand interactions in this protein family and reveal potential target sites for molecular drug design. PMID:11387479

  13. Spacecraft Maximum Allowable Concentrations (SMACs) for C3 to C8 Aliphatic Saturated Aldehydes

    NASA Technical Reports Server (NTRS)

    Langford, Shannon D.

    2007-01-01

    Spacecraft maximum allowable concentrations (SMACs) for C3 to C8, straight-chain, aliphatic aldehydes have been previously assessed and have been documented in volume 4 of Spacecraft Maximum Allowable Concentrations for Selected Airborne Contaminants (James, 2000). These aldehydes as well as associated physical properties are shown in Table 1. The C3 to C8 aliphatic aldehydes can enter the habitable compartments and contaminate breathing air of spacecraft by several routes including incomplete oxidation of alcohols in the Environmental Control and Life Support System (ECLSS) air revitalization subsystem, as a byproduct of human metabolism, through materials off-gassing, or during food preparation. These aldehydes have been detected in the atmosphere of manned space vehicles in the past. Analysis performed by NASA of crew cabin air samples from the Russian Mir Space Station revealed the presence of C3 to C8 aldehydes at concentrations peaking at approximately 0.1 mg/cu m.

  14. C3PO, an endoribonuclease that promotes RNAi by facilitating RISC activation.

    PubMed

    Liu, Ying; Ye, Xuecheng; Jiang, Feng; Liang, Chunyang; Chen, Dongmei; Peng, Junmin; Kinch, Lisa N; Grishin, Nick V; Liu, Qinghua

    2009-08-01

    The catalytic engine of RNA interference (RNAi) is the RNA-induced silencing complex (RISC), wherein the endoribonuclease Argonaute and single-stranded small interfering RNA (siRNA) direct target mRNA cleavage. We reconstituted long double-stranded RNA- and duplex siRNA-initiated RISC activities with the use of recombinant Drosophila Dicer-2, R2D2, and Ago2 proteins. We used this core reconstitution system to purify an RNAi regulator that we term C3PO (component 3 promoter of RISC), a complex of Translin and Trax. C3PO is a Mg2+-dependent endoribonuclease that promotes RISC activation by removing siRNA passenger strand cleavage products. These studies establish an in vitro RNAi reconstitution system and identify C3PO as a key activator of the core RNAi machinery.

  15. Reduction of U(VI) and Toxic Metals by Desulfovibrio Cytochrome C3

    SciTech Connect

    Wall, Judy D

    2013-04-11

    The central objective of our proposed research was twofold: 1) to investigate the structure-function relationship of Desulfovibrio desulfuricans (now Desulfovibrio alaskensis G20) cytochrome c3 with uranium and 2) to elucidate the mechanism for uranium reduction in vitro and in vivo. Physiological analysis of a mutant of D. desulfuricans with a mutation of the gene encoding the type 1 tetraheme cytochrome c3 had demonstrated that uranium reduction was negatively impacted while sulfate reduction was not if lactate were the electron donor. This was thought to be due to the presence of a branched pathway of electron flow from lactate leading to sulfate reduction. Our experimental plan was to elucidate the structural and mechanistic details of uranium reduction involving cytochrome c3.

  16. Downregulation of ClC-3 in dorsal root ganglia neurons contributes to mechanical hypersensitivity following peripheral nerve injury.

    PubMed

    Pang, Rui-Ping; Xie, Man-Xiu; Yang, Jie; Shen, Kai-Feng; Chen, Xi; Su, Ying-Xue; Yang, Chao; Tao, Jing; Liang, Si-Jia; Zhou, Jia-Guo; Zhu, He-Quan; Wei, Xu-Hong; Li, Yong-Yong; Qin, Zhi-Hai; Liu, Xian-Guo

    2016-11-01

    ClC-3 chloride channel/antiporter has been demonstrated to play an important role in synaptic transmission in central nervous system. However, its expression and function in sensory neurons is poorly understood. In present work, we found that ClC-3 is expressed at high levels in dorsal root ganglia (DRG). Co-immunofluorescent data showed that ClC-3 is mainly distributed in A- and C-type nociceptive neurons. ClC-3 expression in DRG is decreased in the spared nerve injury (SNI) model of neuropathic pain. Knockdown of local ClC-3 in DRG neurons with siRNA increased mechanical sensitivity in naïve rats, while overexpression of ClC-3 reversed the hypersensitivity to mechanical stimuli after peripheral nerve injury. In addition, genetic deletion of ClC-3 enhances mouse mechanical sensitivity but did not affect thermal and cold threshold. Restoration of ClC-3 expression in ClC-3 deficient mice reversed the mechanical sensitivity. Mechanistically, loss of ClC-3 enhanced mechanical sensitivity through increasing the excitability of DRG neurons. These data indicate that ClC-3 is an endogenous inhibitor of neuropathic pain development. Downregulation of ClC-3 by peripheral nerve injury is critical for mechanical hypersensitivity. Our findings suggest that ClC-3 is a novel therapeutic target for treating neuropathic pain. PMID:27460962

  17. Downregulation of ClC-3 in dorsal root ganglia neurons contributes to mechanical hypersensitivity following peripheral nerve injury.

    PubMed

    Pang, Rui-Ping; Xie, Man-Xiu; Yang, Jie; Shen, Kai-Feng; Chen, Xi; Su, Ying-Xue; Yang, Chao; Tao, Jing; Liang, Si-Jia; Zhou, Jia-Guo; Zhu, He-Quan; Wei, Xu-Hong; Li, Yong-Yong; Qin, Zhi-Hai; Liu, Xian-Guo

    2016-11-01

    ClC-3 chloride channel/antiporter has been demonstrated to play an important role in synaptic transmission in central nervous system. However, its expression and function in sensory neurons is poorly understood. In present work, we found that ClC-3 is expressed at high levels in dorsal root ganglia (DRG). Co-immunofluorescent data showed that ClC-3 is mainly distributed in A- and C-type nociceptive neurons. ClC-3 expression in DRG is decreased in the spared nerve injury (SNI) model of neuropathic pain. Knockdown of local ClC-3 in DRG neurons with siRNA increased mechanical sensitivity in naïve rats, while overexpression of ClC-3 reversed the hypersensitivity to mechanical stimuli after peripheral nerve injury. In addition, genetic deletion of ClC-3 enhances mouse mechanical sensitivity but did not affect thermal and cold threshold. Restoration of ClC-3 expression in ClC-3 deficient mice reversed the mechanical sensitivity. Mechanistically, loss of ClC-3 enhanced mechanical sensitivity through increasing the excitability of DRG neurons. These data indicate that ClC-3 is an endogenous inhibitor of neuropathic pain development. Downregulation of ClC-3 by peripheral nerve injury is critical for mechanical hypersensitivity. Our findings suggest that ClC-3 is a novel therapeutic target for treating neuropathic pain.

  18. Mixed chimerism and transplant tolerance are not effectively induced in C3a-deficient mice.

    PubMed

    Baśkiewicz-Hałasa, Magdalena; Rogińska, Dorota; Piecyk, Katarzyna; Hałasa, Maciej; Lejkowska, Renata; Pius-Sadowska, Ewa; Machaliński, Bogusław

    2015-01-01

    Mixed chimerism, a phenomenon involved in the development of specific alloantigen tolerance, could be achieved through the transplantation of hematopoietic stem cells into properly prepared recipients. Because the C3a complement component modulates hematopoietic cell trafficking after transplantation, in the present study, we investigated the influence of the C3a deficiency on mixed chimerism and alloantigen tolerance induction. To induce mixed chimerism, C57BL/6J (wild-type strain; H-2K(b); I-E(-)) and B6.129S4-C3(tm1Crr)/J (C3a-deficient) mice were exposed to 3 G total body irradiation (day -1). Subsequently, these mice were treated with CD8-blocking (day -2) and CD40L-blocking (days 0 and 4) antibodies, followed by transplantation with 20 × 10(6) Balb/c (H-2K(d); I-E(+)) bone marrow cells (day 0). The degree of mixed chimerism in peripheral blood leukocytes was measured several times during the 20-week experiment. The tolerance to Balb/c mouse antigens was assessed based on the number of lymphocytes expressing Vβ5 and Vβ11 T-cell receptor and on skin-graft (day 0) acceptance. Applying our experimental model, mixed chimerism and alloantigen tolerance were effectively induced in C57BL/6J (wild-type) mice, but not in C3a(-/-) animals. The present study is, to our knowledge, the first to demonstrate that C3a is vital for achieving stable mixed chimerism and related to this induction of transplant tolerance.

  19. Physicochemical characterization of C3b receptors isolated from human erythrocytes by immunoprecipitation.

    PubMed Central

    Gerdes, J; Stein, H

    1980-01-01

    A high yield of active C3b receptors was obtained by solubilizing human erythrocyte membranes with 2 M KBr, whereas other solubilization agents yielded no, or significantly less activity. Gel filtration of the KBr lysates revealed that the apparent molecular wieght of biologically active C3b receptor molecules was greater than 1 x 10(6). Immunoprecipitates prepared with radio-iodinated KBr lysates and anti-C3 receptor sera (AC3RS) were subjected to sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) or sodium dodecyl gel filtration. Unreduced SDS-PAGE and gel filtration profiles showed three predominant peaks with apparent mol. wts of 1--1.3 x 10(6), 80,000 and 60,000. Whereas the high mol. wt component decreased only slightly after reduction, the 80,000 and 60,000 mol. wt components disappeared and two new peaks with apparent mol. wts of 38,000 and 18,000 appeared in SDS-PAGE profiles. Although the high mol. wt component present in reduced SDS-PAGE profiles was detectable in some of the control experiments, none of the other peaks could be precipitated with control sera, and these components could be demonstrated only when KBr lysates of C3b receptor-positive erythrocytes and AC3RS that were able to inhibit ligand binding of the C3b receptors were used for precipitation. These findings suggest that (a) the C3b receptor of human erythrocytes in its biologically active state is a macromolecule with an apparent mol. wt higher than 1 x 10(6) and (b) the protein moiety consists predominantly of non-covalently linked protein molecules with apparent mol wts of 80,000 and 60,000. These protein molecules are composed of disulphide-bridged polypeptide chains with apparent mol. wts of 38,000 and 18,000. PMID:7461716

  20. Chimpanzee isotopic ecology: a closed canopy C3 template for hominin dietary reconstruction.

    PubMed

    Carlson, Bryce A; Kingston, John D

    2014-11-01

    The most significant hominin adaptations, including features used to distinguish and/or classify taxa, are critically tied to the dietary environment. Stable isotopic analyses of tooth enamel from hominin fossils have provided intriguing evidence for significant C4/CAM (crassulacean acid metabolism) resource consumption in a number of Plio-Pleistocene hominin taxa. Relating isotopic tooth signatures to specific dietary items or proportions of C3 versus C4/CAM plants, however, remains difficult as there is an ongoing need to document and quantify isotopic variability in modern ecosystems. This study investigates the ecological variables responsible for carbon isotopic discrimination and variability within the C3-dominated dietary niche of a closed canopy East African hominoid, Pan troglodytes, from Ngogo, Kibale National Park, Uganda. δ(13)C values among C3 resources utilized by Ngogo chimpanzees were highly variable, ranging over 13‰. Infrequent foraging on papyrus (the only C4 plant consumed by chimpanzees at the site) further extended this isotopic range. Variation was ultimately most attributable to mode of photosynthesis (C3 versus C4), food type, and elevation, which together accounted for approximately 78% of the total sample variation. Among C3 food types, bulk carbon values ranged from -24.2‰ to -31.1‰ with intra-plant variability up to 12.1‰. Pith and sapling leaves were statistically more (13)C depleted than pulp, seeds, flowers, cambium, roots, leaf buds, and leaves from mature trees. The effect of elevation on carbon variation was highly significant and equivalent to an approximately 1‰ increase in δ(13)C for every 150 m of elevation gain, likely reflecting habitat variability associated with topography. These results indicate significant δ(13)C variation attributable to food type and elevation among C3 resources and provide important data for hominin dietary interpretations based on carbon isotopic analyses. PMID:24993419

  1. Development of C3-Symmetric Tris-Urea Low-Molecular-Weight Gelators.

    PubMed

    Yamanaka, Masamichi

    2016-04-01

    This article describes recent developments in C3 -symmetric tris-urea low-molecular-weight gelators and their applications. The C3 -symmetric tris-ureas are excellent frameworks to form supramolecular polymers through noncovalent interactions. In organic solvents, hydrophobic tris-ureas form supramolecular gels. Amphiphilic tris-ureas form supramolecular gels in aqueous media. Functional supramolecular gels were prepared by introducing appropriate functional groups into the outer sphere of tris-ureas. Supramolecular hydrogels obtained from amphiphilic tris-ureas were used in the electrophoresis of proteins. These electrophoreses results showed several unique characteristics compared to typical electrophoreses results obtained using polyacrylamide matrices. PMID:26915980

  2. Correlation between circulating schistosomal antigen, schistosomal complement C3 and intensity of infection.

    PubMed

    Rashed, S M; Khashaba, A; Madwar, M A; Rafik, M M; Abul Fadl, A A; Shash, A M

    1990-06-01

    53.7% of the already parasitologically proved schistosomiasis cases showed circulating schistosomal antigen (C.S.A.) in their sera with significantly higher levels than the controls, with no correlation between the level of C.S.A. and the foecal egg count. Significant higher levels of schistosomal complement C3 were found in schistosomiasis patients as compared to the control group, with no significant difference in the mean level of C3 between patients with positive and negative C.S.A.

  3. A quantum model for bending vibrations and thermodynamic properties of C3.

    NASA Technical Reports Server (NTRS)

    Hansen, C. F.; Pearson, W. E.

    1973-01-01

    The investigation reported was conducted to clarify the thermodynamic properties of C3 by further developing the limit to the partition function suggested by Strauss and Thiele (1967). A quantum solution for the energy levels of a quadratically perturbed square well potential is presented and the consistency of this limit with observed energy levels is established. In the process a more complete physical picture of the bending C3 molecules emerges. The values of entropy deduced from various measurements of graphite pressure are compared with this limit, and the thermodynamic properties predicted for the limiting case are evaluated.

  4. Polymorphic Electronic Circuits

    NASA Technical Reports Server (NTRS)

    Stoica, Adrian

    2004-01-01

    Polymorphic electronics is a nascent technological discipline that involves, among other things, designing the same circuit to perform different analog and/or digital functions under different conditions. For example, a circuit can be designed to function as an OR gate or an AND gate, depending on the temperature (see figure). Polymorphic electronics can also be considered a subset of polytronics, which is a broader technological discipline in which optical and possibly other information- processing systems could also be designed to perform multiple functions. Polytronics is an outgrowth of evolvable hardware (EHW). The basic concepts and some specific implementations of EHW were described in a number of previous NASA Tech Briefs articles. To recapitulate: The essence of EHW is to design, construct, and test a sequence of populations of circuits that function as incrementally better solutions of a given design problem through the selective, repetitive connection and/or disconnection of capacitors, transistors, amplifiers, inverters, and/or other circuit building blocks. The evolution is guided by a search-and-optimization algorithm (in particular, a genetic algorithm) that operates in the space of possible circuits to find a circuit that exhibits an acceptably close approximation of the desired functionality. The evolved circuits can be tested by computational simulation (in which case the evolution is said to be extrinsic), tested in real hardware (in which case the evolution is said to be intrinsic), or tested in random sequences of computational simulation and real hardware (in which case the evolution is said to be mixtrinsic).

  5. 26 CFR 40.6302(c)-3 - Special rules for use of Government depositaries under chapter 33.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... under chapter 33. 40.6302(c)-3 Section 40.6302(c)-3 Internal Revenue INTERNAL REVENUE SERVICE...(c)-3 Special rules for use of Government depositaries under chapter 33. (a) Overview. This section sets forth an alternative method for computing the amount of deposits of taxes imposed by chapter...

  6. 17 CFR 240.15c3-1 - Net capital requirements for brokers or dealers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... forth in Exhibit A, § 240.15c3-3a, on a weekly basis and, in lieu of the 1 percent reduction of certain... Authorities pursuant to 17 CFR 240.17a-11, if the market maker or specialist fails to deposit any required... value of margin securities borrowed from customers in accordance with the provisions of 17 CFR...

  7. Complement C3 Mediated Targeting of Liposomes to Granulocytic Myeloid Derived Suppressor Cells

    PubMed Central

    Kullberg, Max; Martinson, Holly; Mann, Kristine; Anchordoquy, Thomas J.

    2015-01-01

    In cancer patients, granulocytic myeloid derived suppressor cells (G-MDSCs) expand in number, infiltrating tumor and lymphatic tissues where they suppress an anti-tumor immune response. We report here the development of a liposomal drug delivery system that selectively targets GMDSCs. The liposomes form a disulfide bond with activated complement C3 after intravenous injection and are taken up by G-MDSCs, which express the receptor for activated C3. In vitro experiments utilizing serum from a C3 knockout mouse demonstrate that G-MDSCs take up these liposomes in a C3-dependent manner. After systemic administration to tumor bearing mice, liposomes were incorporated by 22% of G-MDSCs in the blood and were also present in a percentage of G-MDSCs in the tumor (11%), spleen (22%), liver (35%) and lungs (26%). This liposomal system offers a versatile means of targeted drug delivery to G-MDSCs and could be an important tool for restoring anti-tumor immunity in cancer patients. PMID:25839391

  8. A visible-light-promoted aerobic metal-free C-3 thiocyanation of indoles.

    PubMed

    Fan, Weigang; Yang, Qi; Xu, Fengshan; Li, Pixu

    2014-11-01

    A simple and efficient visible-light-promoted method for the C-3 thiocyanation of indoles has been developed. The transformation uses Rose Bengal as the photocatalyst and air as the terminal oxidant. The reaction is mild, high-yielding, and environmentally benign.

  9. 76 FR 44800 - Election of Reduced Research Credit Under Section 280C(c)(3)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-27

    ... research credit. The final regulations simplify how taxpayers make the election and affect taxpayers that... return because each member would be required to file a separate Form 6765 to make the election under... 280C(c)(3) is made is generally sufficient to clearly indicate the intent of the common parent to...

  10. Effect of the C(3)-Substituent in Verdazyl Radicals on their Profluorescent Behavior.

    PubMed

    Eusterwiemann, Steffen; Matuschek, David; Stegemann, Linda; Klabunde, Sina; Doerenkamp, Carsten C; Daniliuc, Constantin G; Doltsinis, Nikos L; Strassert, Cristian A; Eckert, Hellmut; Studer, Armido

    2016-01-01

    Methods for the detection of reactive intermediates such as transient radicals are important in organic chemistry, polymer chemistry, biology or medicine. Along these lines we recently reported that 1,5-diphenyl-6-oxo verdazyl radicals can be used as fluorescent spin sensors. In situ generated C-centered radicals are efficiently trapped by the verdazyls, which in turn undergo transformation from a paramagnetic non-fluorescent state to a diamagnetic fluorescent state. Whereas the N-phenyl substituent in the spin probes is of high importance for obtaining profluorescent behavior, the effect of the C(3)-substituent has not been investigated to date. We herein present the synthesis and characterization of various 1,5-diphenyl-6-oxo-verdazyl radicals bearing differently hybridized C-substituents at the C(3) position. Steady-state and time-resolved fluorescence spectroscopy in solution and in the solid state along with time-dependent density functional theory (TDDFT) calculations reveal that a C(3)-aryl substituent is crucial for obtaining fluorescence after spin trapping. In addition, it is shown that the emission wavelength of the C(3)-aryl substituted verdazyl derivatives can be tuned by selective destabilization of the HOMO and the LUMO. PMID:27052756

  11. Redox Equilibria of Cytochrome C3 Immobilised on Self-Assembled Monolayers Coated Silver Electrodes

    NASA Astrophysics Data System (ADS)

    Di Paolo, R. E.; Rivas, L.; Murgida, D.; Hildebrandt, P.

    2005-01-01

    Cytochromes c3 are soluble electron transfer proteins in the periplasm of sulphate-reducing bacteria. They act as electron-proton couplers between hydrogenase and the electron transfer chain of sulphate respiration. In this work, cytochrome c3 (Cyt-c3) obtained from both Desulfovibrio vulgaris and Desulfovibrio gigas, is electrostatically adsorbed on Ag electrodes coated with self-assembled monolayers of 11-mercaptoundecanoic acid. The redox equilibria of the adsorbed tetraheme protein are studied by surface enhanced resonance Raman spectroscopy (SERRS). The quantitative analysis of the SERR spectra, which were measured as a function of the electrode potential, allows determining the redox potentials for the individual hemes of Cyt-c3. The values obtained of the redox potentials are compared with the data provided by NMR experiments and by molecular dynamics simulation studies of the electrostatically bound protein on a coated electrode. It is found that immobilisation causes substantial shifts of the redox potential, which would have an impact on the intramolecular electron flow.

  12. Effect of Ductile Agents on the Dynamic Behavior of SiC3D Network Composites

    NASA Astrophysics Data System (ADS)

    Zhu, Jingbo; Wang, Yangwei; Wang, Fuchi; Fan, Qunbo

    2016-07-01

    Co-continuous SiC ceramic composites using pure aluminum, epoxy, and polyurethane (PU) as ductile agents were developed. The dynamic mechanical behavior and failure mechanisms were investigated experimentally using the split Hopkinson pressure bar (SHPB) method and computationally by finite element (FE) simulations. The results show that the SiC3D/Al composite has the best overall performance in comparison with SiC3D/epoxy and SiC3D/PU composites. FE simulations are generally consistent with experimental data. These simulations provide valuable help in predicting mechanical strength and in interpreting the experimental results and failure mechanisms. They may be combined with micrographs for fracture characterizations of the composites. We found that interactions between the SiC phase and ductile agents under dynamic compression in the SHPB method are complex, and that interfacial condition is an important parameter that determines the mechanical response of SiC3D composites with a characteristic interlocking structure during dynamic compression. However, the effect of the mechanical properties of ductile agents on dynamic behavior of the composites is a second consideration in the production of the composites.

  13. Selective oxidation of alcohols using photoactive VO@g-C3N4.

    EPA Science Inventory

    A photoactive VO@g-C3N4 catalyst has been developed for the selective oxidation of alcohols to the corresponding aldehydes and ketones. The visible light mediated activity of the catalyst could be attributed to photoactive graphitic carbon nitrides surface.

  14. Germination Shifts of C3 and C4 Species under Simulated Global Warming Scenario

    PubMed Central

    Zhang, Hongxiang; Yu, Qiang; Huang, Yingxin; Zheng, Wei; Tian, Yu; Song, Yantao; Li, Guangdi; Zhou, Daowei

    2014-01-01

    Research efforts around the world have been increasingly devoted to investigating changes in C3 and C4 species' abundance or distribution with global warming, as they provide important insight into carbon fluxes and linked biogeochemical cycles. However, changes in the early life stage (e.g. germination) of C3 and C4 species in response to global warming, particularly with respect to asymmetric warming, have received less attention. We investigated germination percentage and rate of C3 and C4 species under asymmetric (+3/+6°C at day/night) and symmetric warming (+5/+5°C at day/night), simulated by alternating temperatures. A thermal time model was used to calculate germination base temperature and thermal time constant. Two additional alternating temperature regimes were used to test temperature metrics effect. The germination percentage and rate increased continuously for C4 species, but increased and then decreased with temperature for C3 species under both symmetric and asymmetric warming. Compared to asymmetric warming, symmetric warming significantly overestimated the speed of germination percentage change with temperature for C4 species. Among the temperature metrics (minimum, maximum, diurnal temperature range and average temperature), maximum temperature was most correlated with germination of C4 species. Our results indicate that global warming may favour germination of C4 species, at least for the C4 species studied in this work. The divergent effects of asymmetric and symmetric warming on plant germination also deserve more attention in future studies. PMID:25137138

  15. Mass spectral analysis of C3 and C4 aliphatic amino acid derivatives.

    NASA Technical Reports Server (NTRS)

    Lawless, J. G.; Chadha, M. S.

    1971-01-01

    Diagnostic criteria are obtained for the distinction of alpha, beta, gamma, and N-methyl isomers of the C3 and C4 aliphatic amino acids, using mass spectral analysis of the derivatives of these acids. The use of deuterium labeling has helped in the understanding of certain fragmentation pathways.

  16. Germination shifts of C3 and C4 species under simulated global warming scenario.

    PubMed

    Zhang, Hongxiang; Yu, Qiang; Huang, Yingxin; Zheng, Wei; Tian, Yu; Song, Yantao; Li, Guangdi; Zhou, Daowei

    2014-01-01

    Research efforts around the world have been increasingly devoted to investigating changes in C3 and C4 species' abundance or distribution with global warming, as they provide important insight into carbon fluxes and linked biogeochemical cycles. However, changes in the early life stage (e.g. germination) of C3 and C4 species in response to global warming, particularly with respect to asymmetric warming, have received less attention. We investigated germination percentage and rate of C3 and C4 species under asymmetric (+3/+6°C at day/night) and symmetric warming (+5/+5°C at day/night), simulated by alternating temperatures. A thermal time model was used to calculate germination base temperature and thermal time constant. Two additional alternating temperature regimes were used to test temperature metrics effect. The germination percentage and rate increased continuously for C4 species, but increased and then decreased with temperature for C3 species under both symmetric and asymmetric warming. Compared to asymmetric warming, symmetric warming significantly overestimated the speed of germination percentage change with temperature for C4 species. Among the temperature metrics (minimum, maximum, diurnal temperature range and average temperature), maximum temperature was most correlated with germination of C4 species. Our results indicate that global warming may favour germination of C4 species, at least for the C4 species studied in this work. The divergent effects of asymmetric and symmetric warming on plant germination also deserve more attention in future studies.

  17. C3Winds: A Novel 3D Wind Observing System to Characterize Severe Weather Events

    NASA Astrophysics Data System (ADS)

    Kelly, M. A.; Wu, D. L.; Yee, J. H.; Boldt, J.; Demajistre, R.; Reynolds, E.; Tripoli, G. J.; Oman, L.; Prive, N.; Heidinger, A. K.; Wanzong, S.

    2015-12-01

    The CubeSat Constellation Cloud Winds (C3Winds) is a NASA Earth Venture Instrument (EV-I) concept with the primary objective to resolve high-resolution 3D dynamic structures of severe wind events. Rapid evolution of severe weather events highlights the need for high-resolution mesoscale wind observations. Yet mesoscale observations of severe weather dynamics are quite rare, especially over the ocean where extratropical and tropical cyclones (ETCs and TCs) can undergo explosive development. Measuring wind velocity at the mesoscale from space remains a great challenge, but is critically needed to understand and improve prediction of severe weather and tropical cyclones. Based on compact, visible/IR imagers and a mature stereoscopic technique, C3Winds has the capability to measure high-resolution (~2 km) cloud motion vectors and cloud geometric heights accurately by tracking cloud features from two formation-flying CubeSats, separated by 5-15 minutes. Complementary to lidar wind measurements from space, C3Winds will provide high-resolution wind fields needed for detailed investigations of severe wind events in occluded ETCs, rotational structures inside TC eyewalls, and ozone injections associated with tropopause folding events. Built upon mature imaging technologies and long history of stereoscopic remote sensing, C3Winds provides an innovative, cost-effective solution to global wind observations with the potential for increased diurnal sampling via CubeSat constellation.

  18. Percutaneous CT-Guided Biopsy of C3 Vertebral Body: Modified Approach for an Old Procedure

    SciTech Connect

    Pua, Uei; Chan, Stephen Yung-Wei

    2013-06-15

    Percutaneous biopsy of upper cervical vertebrae is challenging due to the various critical structures in the location and often requires difficult trajectory such as transoral or paramaxillary approaches. The purpose of this manuscript is to illustrate the utility of head rotation in creating a potential space for direct percutaneous access to C3 vertebral body for safe biopsy.

  19. Structural Analysis of an Open Active Site Conformation of Nonheme Iron Halogenase CytC3

    SciTech Connect

    Wong, Cintyu; Galonic Fujimori, Danica; Walsh, Christopher T.; Drennan, Catherine L.

    2009-04-28

    CytC3, a member of the recently discovered class of nonheme Fe(II) and {alpha}-ketoglutarate ({alpha}KG)-dependent halogenases, catalyzes the double chlorination of l-2-aminobutyric acid (Aba) to produce a known Streptomyces antibiotic, {gamma},{gamma}-dichloroaminobutyrate. Unlike the majority of the Fe(II)-{alpha}KG-dependent enzymes that catalyze hydroxylation reactions, halogenases catalyze a transfer of halides. To examine the important enzymatic features that discriminate between chlorination and hydroxylation, the crystal structures of CytC3 both with and without {alpha}KG/Fe(II) have been solved to 2.2 {angstrom} resolution. These structures capture CytC3 in an open active site conformation, in which no chloride is bound to iron. Comparison of the open conformation of CytC3 with the closed conformation of another nonheme iron halogenase, SyrB2, suggests two important criteria for creating an enzyme-bound FeCl catalyst: (1) the presence of a hydrogen-bonding network between the chloride and surrounding residues, and (2) the presence of a hydrophobic pocket in which the chloride resides.

  20. A survey of cyclopropenylidene (C3H2) in galactic sources.

    PubMed

    Madden, S C; Irvine, W M; Matthews, H E; Friberg, P; Swade, D A

    1989-05-01

    We report the results of an initial survey in a variety of Galactic sources for cyclopropenylidene (C3H2), the first interstellar hydrocarbon ring molecule. C3H2 is found to be very widespread throughout the Galaxy. This, together with its large dipole moment and many observable transitions, makes cyclopropenylidene a promising probe for physical conditions in the interstellar medium. The ortho 1(10)-1(01) transition at 18 GHz is detected in a variety of environments, including giant molecular clouds, diffuse clouds, cold dark clouds, the spiral arm clouds in the direction of distant continuum sources, and the envelope of the carbon star IRC + 10216. The 2(20)-2(11) para line at 21.6 GHz was surveyed in many sources having strong 1(10)-1(01) emission, and, when detected, it was always seen in absorption. A more limited survey of the ortho 2(12)-1(01) transition at 85.3 GHz has been conducted. In addition, the 2(11)-2(02) line of the para species at 46.8 GHz was detected in the dark clouds TMC-1 and L134N. Maps have been made of the clouds TMC-1, L134N, W51, and Orion, confirming that the C3H2 emission is extended in these objects. The data obtained thus far suggest that C3H2 is one of the more abundant organic constituents of the dense interstellar medium.

  1. Aerobic growth of campylobacter in media supplemented with C3-monocarboxylates and C4-dicarboxylates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Experiments were conducted to examine aerobic growth of Campylobacter spp. in media supplemented with C4-dicarboxylates (fumarate, succinate, or malate) and C3-monocarboxylates (pyruvate or lactate). Basal broth media composed of tryptose, yeast extract, and a mineral-vitamin solution was supplement...

  2. Photocatalytic C−H Activation of Hydrocarbons over VO@g‑C3N4

    EPA Science Inventory

    A highly selective and sustainable method has beendeveloped for the oxidation of methyl arenes and their analogues.The VO@g-C3N4 catalyst is very efficient in the C−H activation andoxygen insertion reaction resulting in formation of the correspondingcarbonyl compounds and phenols...

  3. Photosynthetic Characteristics of C3-C4 Intermediate Flaveria Species 1

    PubMed Central

    Rumpho, Mary E.; Ku, Maurice S. B.; Cheng, Shu-Hua; Edwards, Gerald E.

    1984-01-01

    The initial products of photosynthesis by the C3 species Flaveria cronquistii, the C4 species F. trinervia, and the C3-C4 intermediate species F. ramosissima were determined using a pulse-chase technique with 14CO2-12CO2. The intermediate species F. ramosissima incorporated at least 42% of the total soluble 14C fixed into malate and aspartate after 10 seconds of photosynthesis in 14CO2, as compared with 90% for the C4 species F. trinervia and 5% for the C3 species F. cronquistii. In both F. ramosissima and F. trinervia, turnover of labeled malate and aspartate occurred during a chase period in 12CO2, although the rate of turnover was slower in the intermediate species. Relative to F. cronquistii, F. ramosissima showed a reduced incorporation of radioactivity into serine and glycine during the pulse period. These results indicate that a functional C4 pathway of photosynthesis is operating in F. ramosissima which can account for its reduced level of photorespiration, and that this species is a true biochemical intermediate between C3 and C4 plants. PMID:16663775

  4. Bifunctional Ag/C3N4.5 composite nanobelts for photocatalysis and antibacterium.

    PubMed

    Lei, Renbo; Jian, Jikang; Zhang, Zhihua; Song, Bo; Wu, Rong

    2016-09-30

    Multiple functions can be achieved in carbon nitride-based composite nanomaterials by tuning their components and structures. Here, we report on a large-scale synthesis of novel bifunctional Ag/C3N4.5 composite nanobelts (CNBs) with efficient photocatalytic and antibacterial activity. The Ag/C3N4.5 CNBs were synthesized in high yield by a two-step route including a homogeneous precipitation process and a subsequent calcination treatment. The structural, morphological, compositional, and spectroscopic characterizations revealed that the Ag/C3N4.5 CNBs are composed of N-deficient melem ultrathin nanobelts and crystalline Ag nanoparticles attached to the surface of the nanobelts with good contact. The band gap of the Ag/C3N4.5 CNBs is determined to be about 3.04 eV. The efficient photocatalytic and antibacterial activities of the composite nanomaterials are verified by testing the degradation of Rhodamine B (RhB) and the inhibition zone to bacterium E. coli. The work provides a facile route to bifunctional carbon nitride-based composites with potential applications in the fields of the environment and biology.

  5. Association of complement C3 and interleukin-1 with foot infections in diabetic patients

    PubMed Central

    Kheiralla, Z. M. H.; Maklad, S. S.; Ashour, S. M.; El-Sayed Moustafa, E.

    2012-01-01

    The study of the bacteriological profile, the association of complement C3, interleukin-1beta, and zinc therapy of diabetic foot ulcers (type two) was investigated. Twenty diabetics without foot ulcers (group I), 50 diabetics with foot ulcers (group II), and 10 matched normal controls (group III) were enrolled in this study. Diabetic foot ulcers were mostly of grade 2. The most frequent organisms were Clostridium spp., Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli, respectively. Vancomycin, Imipenem, and Meropenem were the most effective against Gram-positive and Gram-negative aerobes, while Imipenem, Meropenem and Chloramphenicol for Gram-positive anaerobes. Group II had abnormal levels of C3 (72%). A significant higher concentration of C3 was found in group II. Group II had abnormal levels of IL-1β (60%). A significant higher concentration of IL-1β was found in group II. Zinc therapy (25 mg/day/oral) induced a highly significant decrease in the frequency of Gram-positive anaerobes and levels of IL-1β. Significantly increases all mineral concentrations in serum level except Mn+2. The study highlights the prevalence of antibiotic multi-drug resistant bacteria causing foot infections in diabetics which require combined antimicrobial therapy. Altered levels of serum complement C3 and IL-1β might be responsible for depressed immune response which might be causes for delayed wound healing and repeated infections. Zinc supplementation may help in healing the wounds by enhancing the immune response. PMID:24688769

  6. Remotely Piloted Vehicle (RPV): Proposed command, control, communications (C3) structure

    NASA Technical Reports Server (NTRS)

    Hughes, R. L.; Evans, W. K.; Howard, W. G.; Wallace, A. S.

    1982-01-01

    The currently proposed command, control, and communications (C3) structure associated with the RPV system, potential problem areas in the transfer of information to and from the RPV system, and options for improving information transfer and estimate the degree of improvement to be expected were identified.

  7. The relationship between complement factor C3, APOE ε4, amyloid and tau in Alzheimer's disease.

    PubMed

    Bonham, Luke W; Desikan, Rahul S; Yokoyama, Jennifer S

    2016-01-01

    Inflammation is becoming increasingly recognized as an important contributor to Alzheimer's disease (AD) pathogenesis. As a part of the innate immune system, the complement cascade enhances the body's ability to destroy and remove pathogens and has recently been shown to influence Alzheimer's associated amyloid and tau pathology. However, little is known in humans about the effects of the complement system and genetic modifiers of AD risk like the ε4 allele of apolioprotein E (APOE ε4) on AD pathobiology. We evaluated cerebrospinal fluid (CSF) protein levels from 267 individuals clinically diagnosed as cognitively normal, mild cognitive impairment, and AD. Using linear models, we assessed the relationship between APOE ε4 genotype, CSF Complement 3 (C3), CSF amyloid-β (amyloid) and CSF hyperphosphorylated tau (ptau). We found a significant interaction between APOE ε4 and CSF C3 on both CSF amyloid and CSF ptau. We also found that CSF C3 is only associated with CSF ptau after accounting for CSF amyloid. Our results support a conceptual model of the AD pathogenic cascade where a synergistic relationship between the complement cascade (C3) and APOE ε4 results in elevated Alzheimer's neurodegeneration and in turn, amyloid further regulates the effect of the complement cascade on downstream tau pathology. PMID:27357286

  8. The optical absorption of triatomic carbon C3 for the wavelength range 260 to 560 nm

    NASA Technical Reports Server (NTRS)

    Jones, J. J.

    1978-01-01

    The spectral absorption properties of C3 have been measured in a shock tube containing a test gas mixture of acetylene diluted with argon. The absorption of a pulsed xenon light source was measured by means of eight photomultiplier channels to a spectrograph and an accompanying drum camera. The postshock test gas temperature and pressure were varied over the range 3240 to 4300 K and 37 to 229 kPa, respectively. The results showed appreciable absorption by C3 for the wavelength range 300 to 540 nm. The various reported measurements of the heat of formation of C3 which are available in the open literature were reviewed, and a value of 198 kcal/mol is recommended. This value, along with best available values for other species, was used to calculate the number density of C3 for the conditions of the present experiments in order to compute absorption cross section or electronic oscillator strength. The computed electronic oscillator strength varied from a high of 0.062 at 3300 K to a low of 0.036 at 3900 K.

  9. Synthesis of 2-substituted tryptophans via a C3- to C2-alkyl migration.

    PubMed

    Mari, Michele; Lucarini, Simone; Bartoccini, Francesca; Piersanti, Giovanni; Spadoni, Gilberto

    2014-01-01

    The reaction of 3-substituted indoles with dehydroalanine (Dha) derivatives under Lewis acid-mediated conditions has been investigated. The formation of 2-substituted tryptophans is proposed to occur through a selective alkylative dearomatization-cyclization followed by C3- to C2-alkyl migration and rearomatization. PMID:25246958

  10. Bifunctional Ag/C3N4.5 composite nanobelts for photocatalysis and antibacterium

    NASA Astrophysics Data System (ADS)

    Lei, Renbo; Jian, Jikang; Zhang, Zhihua; Song, Bo; Wu, Rong

    2016-09-01

    Multiple functions can be achieved in carbon nitride-based composite nanomaterials by tuning their components and structures. Here, we report on a large-scale synthesis of novel bifunctional Ag/C3N4.5 composite nanobelts (CNBs) with efficient photocatalytic and antibacterial activity. The Ag/C3N4.5 CNBs were synthesized in high yield by a two-step route including a homogeneous precipitation process and a subsequent calcination treatment. The structural, morphological, compositional, and spectroscopic characterizations revealed that the Ag/C3N4.5 CNBs are composed of N-deficient melem ultrathin nanobelts and crystalline Ag nanoparticles attached to the surface of the nanobelts with good contact. The band gap of the Ag/C3N4.5 CNBs is determined to be about 3.04 eV. The efficient photocatalytic and antibacterial activities of the composite nanomaterials are verified by testing the degradation of Rhodamine B (RhB) and the inhibition zone to bacterium E. coli. The work provides a facile route to bifunctional carbon nitride-based composites with potential applications in the fields of the environment and biology.

  11. Analytic classification of a class of cuspidal foliations in (C3 , 0)

    NASA Astrophysics Data System (ADS)

    Fernández-Sánchez, Percy; Mozo-Fernández, Jorge; Neciosup, Hernán

    2016-07-01

    In this article we study the analytic classification of certain types of quasi-homogeneous cuspidal holomorphic foliations in (C3 , 0) via the essential holonomy defined over one of the components of the exceptional divisor that appears in the reduction of the singularities of the foliation.

  12. Effect of Ductile Agents on the Dynamic Behavior of SiC3D Network Composites

    NASA Astrophysics Data System (ADS)

    Zhu, Jingbo; Wang, Yangwei; Wang, Fuchi; Fan, Qunbo

    2016-10-01

    Co-continuous SiC ceramic composites using pure aluminum, epoxy, and polyurethane (PU) as ductile agents were developed. The dynamic mechanical behavior and failure mechanisms were investigated experimentally using the split Hopkinson pressure bar (SHPB) method and computationally by finite element (FE) simulations. The results show that the SiC3D/Al composite has the best overall performance in comparison with SiC3D/epoxy and SiC3D/PU composites. FE simulations are generally consistent with experimental data. These simulations provide valuable help in predicting mechanical strength and in interpreting the experimental results and failure mechanisms. They may be combined with micrographs for fracture characterizations of the composites. We found that interactions between the SiC phase and ductile agents under dynamic compression in the SHPB method are complex, and that interfacial condition is an important parameter that determines the mechanical response of SiC3D composites with a characteristic interlocking structure during dynamic compression. However, the effect of the mechanical properties of ductile agents on dynamic behavior of the composites is a second consideration in the production of the composites.

  13. Gas exchange and leaf anatomy of a C3–CAM hybrid, Yucca gloriosa (Asparagaceae)

    PubMed Central

    Heyduk, Karolina; Burrell, Nia; Lalani, Falak; Leebens-Mack, Jim

    2016-01-01

    While the majority of plants use the typical C3 carbon metabolic pathway, ~6% of angiosperms have adapted to carbon limitation as a result of water stress by employing a modified form of photosynthesis known as Crassulacean acid metabolism (CAM). CAM plants concentrate carbon in the cells by temporally separating atmospheric carbon acquisition from fixation into carbohydrates. CAM has been studied for decades, but the evolutionary progression from C3 to CAM remains obscure. In order to better understand the morphological and physiological characteristics associated with CAM photosynthesis, phenotypic variation was assessed in Yucca aloifolia, a CAM species, Yucca filamentosa, a C3 species, and Yucca gloriosa, a hybrid species derived from these two yuccas exhibiting intermediate C3–CAM characteristics. Gas exchange, titratable leaf acidity, and leaf anatomical traits of all three species were assayed in a common garden under well-watered and drought-stressed conditions. Yucca gloriosa showed intermediate phenotypes for nearly all traits measured, including the ability to acquire carbon at night. Using the variation found among individuals of all three species, correlations between traits were assessed to better understand how leaf anatomy and CAM physiology are related. Yucca gloriosa may be constrained by a number of traits which prevent it from using CAM to as high a degree as Y. aloifolia. The intermediate nature of Y. gloriosa makes it a promising system in which to study the evolution of CAM. PMID:26717954

  14. Efficient photocatalytic reduction of CO2 by amine-functionalized g-C3N4

    NASA Astrophysics Data System (ADS)

    Huang, Qian; Yu, Jiaguo; Cao, Shaowen; Cui, Can; Cheng, Bei

    2015-12-01

    Photocatalytic conversion of CO2 into hydrocarbon fuels using semiconductor photocatalysts has attracted great attention, which is considered as a promising approach to resolve the energy shortage and greenhouse effect. In this work, amine-functionalized g-C3N4 was prepared by heating urea at 500 °C, with a subsequent functionalization treatment by monoethanolamine solution. The amine-functionalized g-C3N4 exhibits improved photocatalytic performance on CO2 photoreduction, which can be attributed to the enhanced CO2 adsorption capacity. The optimized photocatalyst shows much higher CO2 conversion efficiency as compared to pure g-C3N4 under the same conditions, with a CH4-production rate of 0.34 μmol h-1 g-1 and CH3OH-production rate of 0.28 μmol h-1 g-1. This work demonstrates the surface amine functionalization is a successful strategy to improve the CO2 adsorption capacity of g-C3N4 for the enhancement of CO2 photoreduction activity.

  15. Growth and Quality of Perennial C3 Grasses in the Southern Great Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spring and fall gaps in forage production for systems utilizing winter wheat forage in the Southern Great Plains have led to an interest in additional resources such as C3 perennial grasses. We evaluated the potential of nine cool-season grass entries for forage production and quality through the fa...

  16. Transportation Command, Control, Communication and Information Systems (C3I): ?Lifting the Lid of Pandora's Box?

    NASA Astrophysics Data System (ADS)

    Grocott, D. F. H.

    Integrated Command, Control, Communication and Information (C3I) Systems have developed a language of their own, drawing heavily on acronyms and information technology terminology, resulting in the impression being given to the uninitiated that either a black art is being practised or at least there is a mystique unknown in other complex systems. No master plan or model exists for C3I systems, and their very existence is predicated primarily on the need to fulfil two basic requirements. First, they exist where there is a need at the highest level of management of an international or national authority, or of a large company, or of a large organization, to exercise real-time optimum use of the total and diverse resources available to the corporate body in pursuit of its mission, charter or commercial goal. Secondly, at the lowest level, C3I systems exist to help an individual, or a machine, or a sensor, to perform a given task or rôle more effectively. The integration of emergency services and the operation of large modern transportation systems are among the civilian systems that stand to gain most from the use of integrated C3I systems.

  17. Complement-dependent cellular cytotoxicity: lymphoblastoid lines that activate complement component 3 (C3) and express C3 receptors have increased sensitivity to lymphocyte-mediated lysis in the presence of fresh human serum.

    PubMed

    Ramos, O F; Sármay, G; Klein, E; Yefenof, E; Gergely, J

    1985-08-01

    Lymphocyte-mediated lysis of cells of the Raji, Daudi, Jijoye, and Bjab lines was elevated when fresh human serum was added to the assay. A higher proportion of effector-target conjugates was observed in the presence of human serum. In similar experiments lysis of 1301, Rael, and P3HR-1 cells was unaltered. All cell lines activated the alternative pathway of complement but they varied in the expression of receptors for complement component 3 (C3) and in the ability to fix the C3 cleavage products on their membrane. The enhancement of lysis in the presence of human serum occurred only with those cells that bound C3. This characteristic was correlated to the expression of C3 receptors. Analysis of the nature of the deposited C3 was performed with Raji cells. Raji cells exposed to human serum bound C3b as indicated by the immunoadherence test. The C3b was further processed to C3bi, because the immunoadherence declined with time and conjugate formation increased with Daudi cells, which carry the C3 receptors CR2 and CR3. This suggests that in the lytic assay lymphocytes with C3bi receptors are recruited in the presence of human serum. We assume that the bridge of C3 molecules between targets and effectors increases the avidity of their interaction. PMID:3895232

  18. Experimental and theoretical study of carbon suboxide C3O2, protonated carbon suboxide C3HO2+ and C3HO2· radical in the gas phase

    NASA Astrophysics Data System (ADS)

    Tortajada, J.; Provot, G.; Morizur, J.-P.; Gal, J.-F.; Maria, P.-C.; Flammang, R.; Govaert, Y.

    1995-02-01

    The proton affinity (PA) of carbon suboxide O=C=C=C=O has been determined by Fourier transform ion cyclotron resonance as 791 kJ mol-1. Ab initio calculations at the MP4(SDTQ)/6-31G**//6-31G** + ZPE(6-31G**) level of theory give a proton affinity for C3O2 of 789 kJ mol-1. The gas-phase reactivity of ions a [O=C=CH---C=O]+ and ions b [O=C=C=C---OH]+, generated from various precursors has been studied by mass spectrometry techniques (metastable ion kinetic energy (MIKE), collision induced decomposition (CID) and neutralization -- reionization (NR) mass spectra). From the experimental and theoretical results it follows that the gas-phase protonation of carbon suboxide yields ion a. At high internal energies these ions show competing losses of H' and CO. The radical [O=C=CH---C=O]·, the neutral counterpart of protonated carbon suboxide, has a lifetime of at least 1 [mu]s.

  19. Compstatin: a C3-targeted complement inhibitor reaching its prime for bedside intervention

    PubMed Central

    Mastellos, Dimitrios C.; Yancopoulou, Despina; Kokkinos, Petros; Huber-Lang, Markus; Hajishengallis, George; Biglarnia, Ali Reza; Lupu, Florea; Nilsson, Bo; Risitano, Antonio M.; Ricklin, Daniel; Lambris, John D.

    2015-01-01

    There is a growing awareness that complement plays an integral role in human physiology and disease, transcending its traditional perception as an accessory system for pathogen clearance and opsonic cell killing. As the list of pathologies linked to dysregulated complement activation grows longer, it has become clear that targeted modulation of this innate immune system opens new windows of therapeutic opportunity for anti-inflammatory drug design. Indeed, the introduction of the first complement-targeting drugs has reignited a vibrant interest in the clinical translation of complement-based inhibitors. Compstatin was discovered as a cyclic peptide that inhibits complement activation by binding C3 and interfering with convertase formation and C3 cleavage. As the convergence point of all activation pathways and a molecular hub for crosstalk with multiple pathogenic pathways, C3 represents an attractive target for therapeutic modulation of the complement cascade. A multidisciplinary drug optimization effort encompassing rational “wet” and in silico synthetic approaches and an array of biophysical, structural, and analytical tools has culminated in an impressive structure-function refinement of compstatin, yielding a series of analogs that show promise for a wide spectrum of clinical applications. These new derivatives have improved inhibitory potency and pharmacokinetic profiles and show efficacy in clinically relevant primate models of disease. This review provides an up-to-date survey of the drug design effort placed on the compstatin family of C3 inhibitors, highlighting the most promising drug candidates. It also discusses translational challenges in complement drug discovery and peptide drug development and reviews concerns related to systemic C3 interception. PMID:25678219

  20. Mesophyll Chloroplast Investment in C3, C4 and C2 Species of the Genus Flaveria.

    PubMed

    Stata, Matt; Sage, Tammy L; Hoffmann, Natalie; Covshoff, Sarah; Ka-Shu Wong, Gane; Sage, Rowan F

    2016-05-01

    The mesophyll (M) cells of C4 plants contain fewer chloroplasts than observed in related C3 plants; however, it is uncertain where along the evolutionary transition from C3 to C4 that the reduction in M chloroplast number occurs. Using 18 species in the genus Flaveria, which contains C3, C4 and a range of C3-C4 intermediate species, we examined changes in chloroplast number and size per M cell, and positioning of chloroplasts relative to the M cell periphery. Chloroplast number and coverage of the M cell periphery declined in proportion to increasing strength of C4 metabolism in Flaveria, while chloroplast size increased with increasing C4 cycle strength. These changes increase cytosolic exposure to the cell periphery which could enhance diffusion of inorganic carbon to phosphenolpyruvate carboxylase (PEPC), a cytosolic enzyme. Analysis of the transcriptome from juvenile leaves of nine Flaveria species showed that the transcript abundance of four genes involved in plastid biogenesis-FtsZ1, FtsZ2, DRP5B and PARC6-was negatively correlated with variation in C4 cycle strength and positively correlated with M chloroplast number per planar cell area. Chloroplast size was negatively correlated with abundance of FtsZ1, FtsZ2 and PARC6 transcripts. These results indicate that natural selection targeted the proteins of the contractile ring assembly to effect the reduction in chloroplast numbers in the M cells of C4 Flaveria species. If so, efforts to engineer the C4 pathway into C3 plants might evaluate whether inducing transcriptome changes similar to those observed in Flaveria could reduce M chloroplast numbers, and thus introduce a trait that appears essential for efficient C4 function. PMID:26985020

  1. Complement C3 Is the Strongest Predictor of Whole-Body Insulin Sensitivity in Psoriatic Arthritis

    PubMed Central

    D’Angelo, Salvatore; Russo, Emilio; Nicolosi, Kassandra; Gallucci, Antonio; Chiaravalloti, Agostino; Bruno, Caterina; Naty, Saverio; De Sarro, Giovambattista; Olivieri, Ignazio; Grembiale, Rosa Daniela

    2016-01-01

    Objectives To evaluate the correlation between inflammatory measures and whole-body insulin sensitivity in psoriatic arthritis (PsA) patients. Methods For the present study, 40 nondiabetic PsA patients were recruited. A standard oral glucose tolerance test (OGTT) was performed. The insulin sensitivity index (ISI), insulinogenic index (IGI) and oral disposition index (ODI) were calculated from dynamic values of glucose and insulin obtained during OGTT. Results In our study population, mean ISI was 3.5 ± 2.5, median IGI was 1.2 (0.7–1.8), mean ODI 4.5 ± 4.5. In univariate correlation analysis, ISI correlated inversely with systolic blood pressure (sBP) (R = -0.52, p = 0.001), diastolic blood pressure (dBP) (R = -0.45, p = 0.004) and complement C3 (R = -0.43, p = 0.006) and ODI correlated inversely with sBP (R = -0.38, p = 0.02), dBP (R = -0.35, p = 0.03) and complement C3 (R = -0.37, p = 0.02). No significant correlations were found between analyzed variables and IGI. In a stepwise multiple regression, only complement C3 entered in the regression equation and accounted for approximately 50% of the variance of ISI. Using a receiver operating characteristic (ROC) curve we identified the best cut-off for complement C3 of 1.32 g/L that yielded a sensitivity of 56% and a specificity of 96% for classification of insulin resistant patients. Conclusions In conclusion, our data suggest that serum complement C3 could represent a useful marker of whole-body insulin sensitivity in PsA patients. PMID:27656896

  2. Initial events during the evolution of C4 photosynthesis in C3 species of Flaveria.

    PubMed

    Sage, Tammy L; Busch, Florian A; Johnson, Daniel C; Friesen, Patrick C; Stinson, Corey R; Stata, Matt; Sultmanis, Stefanie; Rahman, Beshar A; Rawsthorne, Stephen; Sage, Rowan F

    2013-11-01

    The evolution of C4 photosynthesis in many taxa involves the establishment of a two-celled photorespiratory CO2 pump, termed C2 photosynthesis. How C3 species evolved C2 metabolism is critical to understanding the initial phases of C4 plant evolution. To evaluate early events in C4 evolution, we compared leaf anatomy, ultrastructure, and gas-exchange responses of closely related C3 and C2 species of Flaveria, a model genus for C4 evolution. We hypothesized that Flaveria pringlei and Flaveria robusta, two C3 species that are most closely related to the C2 Flaveria species, would show rudimentary characteristics of C2 physiology. Compared with less-related C3 species, bundle sheath (BS) cells of F. pringlei and F. robusta had more mitochondria and chloroplasts, larger mitochondria, and proportionally more of these organelles located along the inner cell periphery. These patterns were similar, although generally less in magnitude, than those observed in the C2 species Flaveria angustifolia and Flaveria sonorensis. In F. pringlei and F. robusta, the CO2 compensation point of photosynthesis was slightly lower than in the less-related C3 species, indicating an increase in photosynthetic efficiency. This could occur because of enhanced refixation of photorespired CO2 by the centripetally positioned organelles in the BS cells. If the phylogenetic positions of F. pringlei and F. robusta reflect ancestral states, these results support a hypothesis that increased numbers of centripetally located organelles initiated a metabolic scavenging of photorespired CO2 within the BS. This could have facilitated the formation of a glycine shuttle between mesophyll and BS cells that characterizes C2 photosynthesis.

  3. Mesophyll Chloroplast Investment in C3, C4 and C2 Species of the Genus Flaveria.

    PubMed

    Stata, Matt; Sage, Tammy L; Hoffmann, Natalie; Covshoff, Sarah; Ka-Shu Wong, Gane; Sage, Rowan F

    2016-05-01

    The mesophyll (M) cells of C4 plants contain fewer chloroplasts than observed in related C3 plants; however, it is uncertain where along the evolutionary transition from C3 to C4 that the reduction in M chloroplast number occurs. Using 18 species in the genus Flaveria, which contains C3, C4 and a range of C3-C4 intermediate species, we examined changes in chloroplast number and size per M cell, and positioning of chloroplasts relative to the M cell periphery. Chloroplast number and coverage of the M cell periphery declined in proportion to increasing strength of C4 metabolism in Flaveria, while chloroplast size increased with increasing C4 cycle strength. These changes increase cytosolic exposure to the cell periphery which could enhance diffusion of inorganic carbon to phosphenolpyruvate carboxylase (PEPC), a cytosolic enzyme. Analysis of the transcriptome from juvenile leaves of nine Flaveria species showed that the transcript abundance of four genes involved in plastid biogenesis-FtsZ1, FtsZ2, DRP5B and PARC6-was negatively correlated with variation in C4 cycle strength and positively correlated with M chloroplast number per planar cell area. Chloroplast size was negatively correlated with abundance of FtsZ1, FtsZ2 and PARC6 transcripts. These results indicate that natural selection targeted the proteins of the contractile ring assembly to effect the reduction in chloroplast numbers in the M cells of C4 Flaveria species. If so, efforts to engineer the C4 pathway into C3 plants might evaluate whether inducing transcriptome changes similar to those observed in Flaveria could reduce M chloroplast numbers, and thus introduce a trait that appears essential for efficient C4 function.

  4. Global modeling of the C1-C3 alkyl nitrates using STOCHEM-CRI

    NASA Astrophysics Data System (ADS)

    Khan, M. A. H.; Cooke, M. C.; Utembe, S. R.; Morris, W. C.; Archibald, A. T.; Derwent, R. G.; Jenkin, M. E.; Orr-Ewing, A. J.; Higgins, C. M.; Percival, C. J.; Leather, K. E.; Shallcross, D. E.

    2015-12-01

    The atmospheric global budget and distribution of C1-C3 alkyl nitrates have been investigated using a global three-dimensional chemistry transport model, STOCHEM-CRI. Alkyl nitrates (RONO2) are significant NOx reservoir species and the more detailed VOC oxidation mechanism (CRI v2-R5) leads to greater photochemical production. RONO2 are significant sources of NOx in regions remote from NOx sources. The study shows that the global burden and the atmospheric life-time of C1-C3 alkyl nitrates are 113 Gg and 9-10 days, respectively, which are in excellent agreement with estimates established by previous studies. The abundance of alkyl nitrates have been found to be higher in the continental atmosphere, with CH3ONO2 mixing ratios up to 20 ppt over the Amazon rainforest. Up to 15, 10, 2, and 5 ppt of modelled CH3ONO2, C2H5ONO2, n-C3H7ONO2 and i-C3H7ONO2 have been found in the northern hemisphere over regions with large anthropogenic emissions of NOx and VOCs. The combination of atmospheric production and long-range transport led to high alkyl nitrate levels at high latitudes. The model performance for C1-C3 alkyl nitrates was established using observations from nine flights and nine field campaigns. The comparison shows a tendency towards model under-prediction of the observations, particularly in the southern hemispheric marine boundary layer, possibly due to the absence of oceanic production mechanisms and air-sea exchange processes in the model. The discrepancies between model and observed seasonal cycles, especially of CH3ONO2, in both hemispheres are discussed.

  5. Human C3 mutation reveals a mechanism of dense deposit disease pathogenesis and provides insights into complement activation and regulation

    PubMed Central

    Martínez-Barricarte, Rubén; Heurich, Meike; Valdes-Cañedo, Francisco; Vazquez-Martul, Eduardo; Torreira, Eva; Montes, Tamara; Tortajada, Agustín; Pinto, Sheila; Lopez-Trascasa, Margarita; Morgan, B. Paul; Llorca, Oscar; Harris, Claire L.; Rodríguez de Córdoba, Santiago

    2010-01-01

    Dense deposit disease (DDD) is a severe renal disease characterized by accumulation of electron-dense material in the mesangium and glomerular basement membrane. Previously, DDD has been associated with deficiency of factor H (fH), a plasma regulator of the alternative pathway (AP) of complement activation, and studies in animal models have linked pathogenesis to the massive complement factor 3 (C3) activation caused by this deficiency. Here, we identified a unique DDD pedigree that associates disease with a mutation in the C3 gene. Mutant C3923ΔDG, which lacks 2 amino acids, could not be cleaved to C3b by the AP C3-convertase and was therefore the predominant circulating C3 protein in the patients. However, upon activation to C3b by proteases, or to C3(H2O) by spontaneous thioester hydrolysis, C3923ΔDG generated an active AP C3-convertase that was regulated normally by decay accelerating factor (DAF) but was resistant to decay by fH. Moreover, activated C3b923ΔDG and C3(H2O)923ΔDG were resistant to proteolysis by factor I (fI) in the presence of fH, but were efficiently inactivated in the presence of membrane cofactor protein (MCP). These characteristics cause a fluid phase–restricted AP dysregulation in the patients that continuously activated and consumed C3 produced by the normal C3 allele. These findings expose structural requirements in C3 that are critical for recognition of the substrate C3 by the AP C3-convertase and for the regulatory activities of fH, DAF, and MCP, all of which have implications for therapeutic developments. PMID:20852386

  6. Polymorphic Evolutionary Games.

    PubMed

    Fishman, Michael A

    2016-06-01

    In this paper, I present an analytical framework for polymorphic evolutionary games suitable for explicitly modeling evolutionary processes in diploid populations with sexual reproduction. The principal aspect of the proposed approach is adding diploid genetics cum sexual recombination to a traditional evolutionary game, and switching from phenotypes to haplotypes as the new game׳s pure strategies. Here, the relevant pure strategy׳s payoffs derived by summing the payoffs of all the phenotypes capable of producing gametes containing that particular haplotype weighted by the pertinent probabilities. The resulting game is structurally identical to the familiar Evolutionary Games with non-linear pure strategy payoffs (Hofbauer and Sigmund, 1998. Cambridge University Press), and can be analyzed in terms of an established analytical framework for such games. And these results can be translated into the terms of genotypic, and whence, phenotypic evolutionary stability pertinent to the original game.

  7. Step 1: Human System Integration (HSI) FY05 Pilot-Technology Interface Requirements for Command, Control, and Communications (C3)

    NASA Technical Reports Server (NTRS)

    2005-01-01

    The document provides the Human System Integration(HSI) high-level functional C3 HSI requirements for the interface to the pilot. Description includes (1) the information required by the pilot to have knowledge C3 system status, and (2) the control capability needed by the pilot to obtain C3 information. Fundamentally, these requirements provide the candidate C3 technology concepts with the necessary human-related elements to make them compatible with human capabilities and limitations. The results of the analysis describe how C3 operations and functions should interface with the pilot to provide the necessary C3 functionality to the UA-pilot system. Requirements and guidelines for C3 are partitioned into three categories: (1) Pilot-Air Traffic Control (ATC) Voice Communications (2) Pilot-ATC Data Communications, and (3) command and control of the unmanned aircraft (UA). Each requirement is stated and is supported with a rationale and associated reference(s).

  8. Gene Polymorphisms in Chronic Periodontitis

    PubMed Central

    Laine, Marja L.; Loos, Bruno G.; Crielaard, W.

    2010-01-01

    We aimed to conduct a review of the literature for gene polymorphisms associated with chronic periodontitis (CP) susceptibility. A comprehensive search of the literature in English was performed using the keywords: periodontitis, periodontal disease, combined with the words genes, mutation, or polymorphism. Candidate gene polymorphism studies with a case-control design and reported genotype frequencies in CP patients were searched and reviewed. There is growing evidence that polymorphisms in the IL1, IL6, IL10, vitamin D receptor, and CD14 genes may be associated with CP in certain populations. However, carriage rates of the rare (R)-allele of any polymorphism varied considerably among studies and most of the studies appeared under-powered and did not correct for other risk factors. Larger cohorts, well-defined phenotypes, control for other risk factors, and analysis of multiple genes and polymorphisms within the same pathway are needed to get a more comprehensive insight into the contribution of gene polymorphisms in CP. PMID:20339487

  9. C3-Luc Cells Are an Excellent Model for Evaluation of Cellular Immunity following HPV16L1 Vaccination

    PubMed Central

    Li, Li-Li; Wang, He-Rong; Zhou, Zhi-Yi; Luo, Jing; Wang, Xiao-Li; Xiao, Xiang-Qian; Zhou, Yu-Bai; Zeng, Yi

    2016-01-01

    C3 and TC-1 are the two model cell lines most commonly used in studies of vaccines and drugs against human papillomavirus (HPV) infection. Because C3 cells contain both the HPV16 E and L genes, but TC-1 cells contain only the HPV16 E genes, C3 cells are usually used as the model cell line in studies targeting the HPV16 L protein. However, expression of the L1 protein is difficult to detect in C3 cells using common methods. In our study, Short tandem repeat analysis (STR) was used to demonstrate that C3 cells are indeed derived from mice, PCR results show that HPV16 L1, E6 and E7 genes were detected in C3 genomic DNA, and RT-PCR results demonstrated that L1 transcription had occurred in C3 cells. However, the expression of C3 protein was not found in the results of western blot and immunohistochemistry (IHC). Growth and proliferation of C3 were inhibited by mice spleen lymphocytes that had been immunized with a vaccine against HPV16L1. The luciferase gene was integrated into C3 cells, and it was confirmed that addition of the exogenous gene had no effect on C3 cells by comparing cell growth and tumor formation with untransformed cells. Cells stably expressing luciferase (C3-luc) were screened and subcutaneously injected into the mice. Tumors became established and were observed using a Spectrum Pre-clinical in Vivo Imaging System. Tumor size of mice in the different groups at various time points was calculated by counting photons. The sensitivity of the animals to the vaccine was quantified by statistical comparison. Ten or 30 days following injection of the C3-luc cells, tumor size differed significantly between the PBS and vaccine groups, indicating that C3 cells were susceptible to vaccination even after tumors were formed in vivo. PMID:26900913

  10. C3 Promotes Expansion of CD8+ and CD4+ T cells in a Listeria monocytogenes infection

    PubMed Central

    Nakayama, Yumi; Kim, Shin-Il; Kim, Eui Ho; Lambris, John D.; Sandor, Matyas; Suresh, M.

    2009-01-01

    It is known that C3 is required for optimal expansion of T cells during acute viral infections. However, it is not yet determined whether T cell responses to intracellular bacterial infections require C3. Therefore, we have investigated the requirement for C3 to elicit potent T cell responses to Listeria monocytogenes (LM). We show that expansion of antigen-specific CD8 and CD4 T cells during a primary response to LM was markedly reduced in the absence of C3 activity. Further studies indicated that, unlike in an influenza virus infection, the regulation of LM-specific T cell responses by C3 might not involve the downstream effector C5a. Moreover, reduced T cell responses to LM was not linked to defective maturation of DCs or developmental anomalies in the peripheral T cell compartment of C3-deficient mice. Experiments involving adoptive transfer of C3-deficient CD8 T cells into the C3-sufficient environment of wild type mice showed that these T cells do not have intrinsic proliferative defects and paracrine source of C3 will suffice for clonal expansion of CD8 T cells in vivo. However, stimulation of purified C3-deficient CD8 T cells by plastic-immobilized anti-CD3 showed that C3 promotes T cell proliferation directly, independent of its effects on antigen-presenting cells. Based on these findings, we propose that diminished T cell responses to LM in C3-deficient mice might be at least in part due to lack of direct effects of C3 on T cells. These studies have furthered our understanding of C3-mediated regulation of T cell immunity to intracellular pathogens. PMID:19648268

  11. Delineation of the complement receptor type 2-C3d complex by site-directed mutagenesis and molecular docking.

    PubMed

    Shaw, Craig D; Storek, Michael J; Young, Kendra A; Kovacs, James M; Thurman, Joshua M; Holers, V Michael; Hannan, Jonathan P

    2010-12-10

    The interactions between the complement receptor type 2 (CR2) and the C3 complement fragments C3d, C3dg, and iC3b are essential for the initiation of a normal immune response. A crystal-derived structure of the two N-terminal short consensus repeat (SCR1-2) domains of CR2 in complex with C3d has previously been elucidated. However, a number of biochemical and biophysical studies targeting both CR2 and C3d appear to be in conflict with these structural data. Previous mutagenesis and heteronuclear NMR spectroscopy studies directed toward the C3d-binding site on CR2 have indicated that the CR2-C3d cocrystal structure may represent an encounter/intermediate or nonphysiological complex. With regard to the CR2-binding site on C3d, mutagenesis studies by Isenman and coworkers [Isenman, D. E., Leung, E., Mackay, J. D., Bagby, S. & van den Elsen, J. M. H. (2010). Mutational analyses reveal that the staphylococcal immune evasion molecule Sbi and complement receptor 2 (CR2) share overlapping contact residues on C3d: Implications for the controversy regarding the CR2/C3d cocrystal structure. J. Immunol. 184, 1946-1955] have implicated an electronegative "concave" surface on C3d in the binding process. This surface is discrete from the CR2-C3d interface identified in the crystal structure. We generated a total of 18 mutations targeting the two (X-ray crystallographic- and mutagenesis-based) proposed CR2 SCR1-2 binding sites on C3d. Using ELISA analyses, we were able to assess binding of mutant forms of C3d to CR2. Mutations directed toward the concave surface of C3d result in substantially compromised CR2 binding. By contrast, targeting the CR2-C3d interface identified in the cocrystal structure and the surrounding area results in significantly lower levels of disruption in binding. Molecular modeling approaches used to investigate disparities between the biochemical data and the X-ray structure of the CR2-C3d cocrystal result in highest-scoring solutions in which CR2 SCR1-2 is

  12. Delineation of the complement receptor type 2-C3d complex by site-directed mutagenesis and molecular docking.

    PubMed

    Shaw, Craig D; Storek, Michael J; Young, Kendra A; Kovacs, James M; Thurman, Joshua M; Holers, V Michael; Hannan, Jonathan P

    2010-12-10

    The interactions between the complement receptor type 2 (CR2) and the C3 complement fragments C3d, C3dg, and iC3b are essential for the initiation of a normal immune response. A crystal-derived structure of the two N-terminal short consensus repeat (SCR1-2) domains of CR2 in complex with C3d has previously been elucidated. However, a number of biochemical and biophysical studies targeting both CR2 and C3d appear to be in conflict with these structural data. Previous mutagenesis and heteronuclear NMR spectroscopy studies directed toward the C3d-binding site on CR2 have indicated that the CR2-C3d cocrystal structure may represent an encounter/intermediate or nonphysiological complex. With regard to the CR2-binding site on C3d, mutagenesis studies by Isenman and coworkers [Isenman, D. E., Leung, E., Mackay, J. D., Bagby, S. & van den Elsen, J. M. H. (2010). Mutational analyses reveal that the staphylococcal immune evasion molecule Sbi and complement receptor 2 (CR2) share overlapping contact residues on C3d: Implications for the controversy regarding the CR2/C3d cocrystal structure. J. Immunol. 184, 1946-1955] have implicated an electronegative "concave" surface on C3d in the binding process. This surface is discrete from the CR2-C3d interface identified in the crystal structure. We generated a total of 18 mutations targeting the two (X-ray crystallographic- and mutagenesis-based) proposed CR2 SCR1-2 binding sites on C3d. Using ELISA analyses, we were able to assess binding of mutant forms of C3d to CR2. Mutations directed toward the concave surface of C3d result in substantially compromised CR2 binding. By contrast, targeting the CR2-C3d interface identified in the cocrystal structure and the surrounding area results in significantly lower levels of disruption in binding. Molecular modeling approaches used to investigate disparities between the biochemical data and the X-ray structure of the CR2-C3d cocrystal result in highest-scoring solutions in which CR2 SCR1-2 is

  13. C3-induced release of neurotrophic factors from Schwann cells - potential mechanism behind its regeneration promoting activity.

    PubMed

    Rohrbeck, Astrid; Stahl, Frank; Höltje, Markus; Hettwer, Timo; Lindner, Patrick; Hagemann, Sandra; Pich, Andreas; Haastert-Talini, Kirsten

    2015-11-01

    Previous studies revealed a peripheral nerve regeneration (PNR)(1) promoting activity of Clostridium botulinum C3(2) exoenzyme or a 26(mer) C-terminal peptide fragment covering amino acids 156-181 (C3(156-181)),(3) when delivered as one-time injection at the lesion site. The current study was performed to 1) investigate if prolonged availability of C3 and C3(156-181) at the lesion site can further enhance PNR in vivo and to 2) elucidate effects of C3 and C3(156-181) on Schwann cells (SCs)(4)in vitro. For in vivo studies, 10 mm adult rat sciatic nerve gaps were reconstructed with the epineurial pouch technique or autologous nerve grafts. Epineurial pouches were filled with a hydrogel containing i) vehicle, ii) 40 μM C3 or iii) 40 μM C3(156-181). Sensory and motor functional recovery was monitored over 12 weeks and the outcome of PNR further analyzed by nerve morphometry. In vitro, we compared gene expression profiles (microarray analysis) and neurotrophic factor expression (western blot analysis) of untreated rat neonatal SCs with those treated with C3 or C3(156-181) for 72 h. Effects on neurotrophic factor expression levels were proven in adult human SCs. Unexpectedly, prolonged delivery of C3 and C3(156-181) at the lesion site did not increase the outcome of PNR. Regarding the potential mechanism underlying their previously detected PNR promoting action, however, 6 genes were found to be commonly altered in SCs upon treatment with C3 or C3(156-181). We demonstrate significant down-regulation of genes involved in glutamate uptake (Eaac1,(5)Grin2a(6)) and changes in neurotrophic factor expression (increase of FGF-2(7) and decrease of NGF(8)). Our microarray-based expression profiling revealed novel C3-regulated genes in SCs possibly involved in the axonotrophic (regeneration promoting) effects of C3 and C3(156-181). Detection of altered neurotrophic factor expression by C3 or C3(156-181) treated primary neonatal rat SCs and primary adult human SCs supports

  14. Anthracycline resistance mediated by reductive metabolism in cancer cells: The role of aldo-keto reductase 1C3

    SciTech Connect

    Hofman, Jakub; Malcekova, Beata; Skarka, Adam; Novotna, Eva; Wsol, Vladimir

    2014-08-01

    Pharmacokinetic drug resistance is a serious obstacle that emerges during cancer chemotherapy. In this study, we investigated the possible role of aldo-keto reductase 1C3 (AKR1C3) in the resistance of cancer cells to anthracyclines. First, the reducing activity of AKR1C3 toward anthracyclines was tested using incubations with a purified recombinant enzyme. Furthermore, the intracellular reduction of daunorubicin and idarubicin was examined by employing the transfection of A549, HeLa, MCF7 and HCT 116 cancer cells with an AKR1C3 encoding vector. To investigate the participation of AKR1C3 in anthracycline resistance, we conducted MTT cytotoxicity assays with these cells, and observed that AKR1C3 significantly contributes to the resistance of cancer cells to daunorubicin and idarubicin, whereas this resistance was reversible by the simultaneous administration of 2′-hydroxyflavanone, a specific AKR1C3 inhibitor. In the final part of our work, we tracked the changes in AKR1C3 expression after anthracycline exposure. Interestingly, a reciprocal correlation between the extent of induction and endogenous levels of AKR1C3 was recorded in particular cell lines. Therefore, we suggest that the induction of AKR1C3 following exposure to daunorubicin and idarubicin, which seems to be dependent on endogenous AKR1C3 expression, eventually might potentiate an intrinsic resistance given by the normal expression of AKR1C3. In conclusion, our data suggest a substantial impact of AKR1C3 on the metabolism of daunorubicin and idarubicin, which affects their pharmacokinetic and pharmacodynamic behavior. In addition, we demonstrate that the reduction of daunorubicin and idarubicin, which is catalyzed by AKR1C3, contributes to the resistance of cancer cells to anthracycline treatment. - Highlights: • Metabolism of anthracyclines by AKR1C3 was studied at enzyme and cellular levels. • Anthracycline resistance mediated by AKR1C3 was demonstrated in cancer cells. • Induction of AKR1C3

  15. Antibody-mediated complement C3b/iC3b binding to group B Streptococcus in paired mother and baby serum samples in a refugee population on the Thailand-Myanmar border.

    PubMed

    Herbert, Jenny; Thomas, Stephen; Brookes, Charlotte; Turner, Claudia; Turner, Paul; Nosten, Francois; Le Doare, Kirsty; Hudson, Michael; Heath, Paul T; Gorringe, Andrew; Taylor, Stephen

    2015-03-01

    Streptococcus agalactiae (group B streptococcus [GBS]) is the leading cause of neonatal sepsis and meningitis. In this study, we determined antibody-mediated deposition of complement C3b/iC3b onto the bacterial cell surface of GBS serotypes Ia, Ib, II, III, and V. This was determined for 520 mother and umbilical cord serum sample pairs obtained at the time of birth from a population on the Thailand-Myanmar border. Antibody-mediated deposition of complement C3b/iC3b was detected to at least one serotype in 91% of mothers, despite a known carriage rate in this population of only 12%. Antibody-mediated C3b/iC3b deposition corresponded to known carriage rates, with the highest levels of complement deposition observed onto the most prevalent serotype (serotype II) followed by serotypes Ia, III, V, and Ib. Finally, neonates born to mothers carrying serotype II GBS at the time of birth showed higher antibody-mediated C3b/iC3b deposition against serotype II GBS than neonates born to mothers with no serotype II carriage. Assessment of antibody-mediated C3b/iC3b deposition against GBS may provide insights into the seroepidemiology of anti-GBS antibodies in mothers and infants in different populations. PMID:25589553

  16. Generation of three different fragments of bound C3 with purified factor I or serum. II. Location of binding sites in the C3 Fragments for Factors B and H, complement receptors , and bovine conglutinin

    PubMed Central

    Ross, GD; Newman, SL; Lambris, JD; Devery-Pocius, JE; Cain, JA; Lackmann, PJ

    1983-01-01

    The many different recognized functions of C3 are dependent upon the ability of the activated C3 molecule both to bind covalently to protein and carbohydrate surfaces and to provide binding sites for as many as eleven different proteins. The location of the binding sites for six of these different proteins (factors B and H, complement receptors CR(1), CR(2) and CR(3) and conglutinin) was examined in the naturally occurring C3-fragments generated by C3 activation (C3b) and degradation by Factor I (iC3b, C3c, C3d,g) and trypsin (C3d). Evidence was obtained for at least four distinct binding sites in C3 for these six different C3 ligands. One binding site for B was detectable only in C3b, whereas a second binding site for H and CR(1) was detectable in both C3b and iC3b. The affinity of the binding site for H and CR(1) was charge dependent and considerably reduced in iC3b as compared to C3b. H binding to iC3b-coated sheep erythrocytes (EC3bi) was measurable only in low ionic strength buffer (4 mS). The finding that C3c-coated microspheres bound to CR(1), indicated that this second binding site was still intact in the C3c fragment. However, H binding to C3c was not examined. A third binding site in C3 for CR(2) was exposed in the d region by factor I cleavage of C3b into iC3b, and the activity of this site was unaffected by the further I cleavage of iC3b into C3d,g. Removal of the 8,000-dalton C3g fragment from C3d,g with trypsin forming C3d, resulted in reduced CR2 activity. However, because saturating amounts of monoclonal anti-C3g did not block the CR(2)-binding activity of EC3d,g, it appears unlikely that the g region of C3d,g or iC3b forms a part of the CR(2)-binding site. In addition, detergent-solubilized EC3d (C3d-OR) inhibited the CR(2)-binding activity of EC3d,g. Monocytes and neutrophils, that had been previously thought to lack CR(2) because of their inability to form EC3d rosettes, did bind EC3d,g containing greater than 5 × 10(4) C3d,g molecules per E

  17. Antibody-Mediated Complement C3b/iC3b Binding to Group B Streptococcus in Paired Mother and Baby Serum Samples in a Refugee Population on the Thailand-Myanmar Border

    PubMed Central

    Herbert, Jenny; Thomas, Stephen; Brookes, Charlotte; Turner, Claudia; Turner, Paul; Nosten, Francois; Le Doare, Kirsty; Hudson, Michael; Heath, Paul T.; Gorringe, Andrew

    2015-01-01

    Streptococcus agalactiae (group B streptococcus [GBS]) is the leading cause of neonatal sepsis and meningitis. In this study, we determined antibody-mediated deposition of complement C3b/iC3b onto the bacterial cell surface of GBS serotypes Ia, Ib, II, III, and V. This was determined for 520 mother and umbilical cord serum sample pairs obtained at the time of birth from a population on the Thailand-Myanmar border. Antibody-mediated deposition of complement C3b/iC3b was detected to at least one serotype in 91% of mothers, despite a known carriage rate in this population of only 12%. Antibody-mediated C3b/iC3b deposition corresponded to known carriage rates, with the highest levels of complement deposition observed onto the most prevalent serotype (serotype II) followed by serotypes Ia, III, V, and Ib. Finally, neonates born to mothers carrying serotype II GBS at the time of birth showed higher antibody-mediated C3b/iC3b deposition against serotype II GBS than neonates born to mothers with no serotype II carriage. Assessment of antibody-mediated C3b/iC3b deposition against GBS may provide insights into the seroepidemiology of anti-GBS antibodies in mothers and infants in different populations. PMID:25589553

  18. NPOESS C3S Expandability: SafetyNet(TM) and McMurdo Improvements

    NASA Astrophysics Data System (ADS)

    Paciaroni, J.; Jamilkowski, M. L.

    2009-12-01

    The National Oceanic & Atmospheric Administration (NOAA), Department of Defense (DoD), and National Aeronautics and Space Administration (NASA) are jointly acquiring the next-generation weather and environmental satellite system; the National Polar-orbiting Operational Environmental Satellite System (NPOESS). NPOESS replaces the current Polar-orbiting Operational Environmental Satellites (POES) managed by NOAA and the Defense Meteorological Satellite Program (DMSP) managed by the DoD. The NPOESS satellites carry a suite of sensors that collect meteorological, oceanographic, climatological, and solar-geophysical observations of the earth, atmosphere, and space. The command and telemetry portion of NPOESS is the Command, Control and Communications Segment (C3S), developed by Raytheon Intelligence & Information Systems. C3S is responsible for managing the overall NPOESS mission from control and status of the space and ground assets to ensuring delivery of timely, high quality data from the Space Segment (SS) to the Interface Data Processing Segment (IDPS) for processing. In addition, the C3S provides the globally distributed ground assets necessary to collect and transport mission, telemetry, and command data between the satellites and the processing locations. The C3S provides all functions required for day-to-day commanding and state-of-health monitoring of the NPP and NPOESS satellites, and delivery of Stored Mission Data (SMD) to each U.S. Weather Central Interface Data Processor (IDP) for data products development and transfer to System subscribers. The C3S also monitors and reports system-wide health and status and data communications with external systems and between the NPOESS segments. Two crucial elements of NPOESS C3S expandability are SafetyNet(TM) and communications improvements to McMurdo Station, Antarctica. ‘SafetyNet(TM)’ is a key feature of the National Polar-orbiting Operational Environmental Satellite System (NPOESS), vital element of the C3S

  19. NPOESS C3S Expandability: SafetyNetTM and McMurdo Improvements

    NASA Astrophysics Data System (ADS)

    Jamilkowski, M. L.; Paciaroni, J.; Pela, F.

    2010-12-01

    The National Oceanic & Atmospheric Administration (NOAA), Department of Defense (DoD), and National Aeronautics & Space Administration (NASA) are jointly acquiring the next-generation weather & environmental satellite system; the National Polar-orbiting Operational Environmental Satellite System (NPOESS). NPOESS replaces the current NOAA Polar-orbiting Operational Environmental Satellites (POES) and Dod's Defense Meteorological Satellite Program (DMSP). The NPOESS satellites carry a suite of sensors that collect meteorological, oceanographic, climatological, and solar-geophysical observations of the earth, atmosphere, and space. The command & telemetry portion of NPOESS is the Command, Control and Communications Segment (C3S), developed by Raytheon Intelligence & Information Systems. C3S is responsible for managing the overall NPOESS mission from control and status of the space and ground assets to ensuring delivery of timely, high quality data from the Space Segment (SS) to the Interface Data Processing Segment (IDPS) for processing. In addition, the C3S provides the globally distributed ground assets necessary to collect and transport mission, telemetry, and command data between the satellites and the processing locations. The C3S provides all functions required for day-to-day commanding & state-of-health monitoring of the NPP & NPOESS satellites, and delivery of Stored Mission Data (SMD) to each US Weather Central Interface Data Processor (IDP) for data products development and transfer to System subscribers. The C3S also monitors and reports system-wide health and status & data communications with external systems and between NPOESS segments. Two crucial elements of NPOESS C3S expandability are SafetyNetTM and communications improvements to McMurdo Station, Antarctica. SafetyNetTM is a key feature of NPOESS and a vital element of the C3S and Northrop Grumman Aerospace Systems patented data collection architecture. The centerpiece of SafetyNetTM is the system of

  20. Lack of carcinogenicity of tragacanth gum in B6C3F1 mice.

    PubMed

    Hagiwara, A; Boonyaphiphat, P; Kawabe, M; Naito, H; Shirai, T; Ito, N

    1992-08-01

    Tragacanth gum was administered at dietary levels of 0 (control), 1.25 and 5.0% to groups of 50 male and 50 female B6C3F1 mice for 96 wk after which all animals were maintained on a basal diet without tragacanth gum for a further 10 wk. Mean body weights of females in the 5.0% and 1.25% groups were lower than those of the controls after 11 and 16 wk, respectively. However, there were no treatment-related clinical signs or adverse effects on survival rate, urinalysis, haematology, blood biochemistry and organ weight. While detailed histopathology revealed the development of squamous cell hyperplasias, papillomas and one carcinoma in the forestomach, there was no significant treatment-related increase in the incidence of any preneoplastic or neoplastic lesion. Thus, under the experimental conditions used, tragacanth gum was not carcinogenic in B6C3F1 mice of either sex.

  1. Unexpected Complication with the New C3 Excluder: Cause and Treatment

    SciTech Connect

    Katsargyris, Athanasios; Oikonomou, Kyriakos; Bracale, Umberto M.; Verhoeven, Eric L. G.

    2013-04-15

    The new C3 Gore Excluder delivery system enables both up/downward and rotational repositioning of the device before complete deployment. This contributes to more precise proximal landing and permits facilitation of the contralateral gate cannulation. During separate deployment, the position of the ipsilateral limb can also be readjusted. We have used the modified C3 delivery system in more than 50 patients, and in most cases, we were able to utilize the repositioning options of the device to achieve optimal fixation and sealing. However, we present a case where our attempt to readjust the position of the ipsilateral limb led to upward migration of the main body with coverage of the left renal artery origin. The latter was secured with a bare stent implantation.

  2. Effects of curvilinear motion in large-amplitude bending of C3

    NASA Technical Reports Server (NTRS)

    Hansen, C. F.; Pearson, W. E.; Henderson, B. J.

    1974-01-01

    The geometry of the bending of a linear triatomic molecule is analyzed, and an expression for the average rotational constant is derived. A harmonic oscillator model of C3 is fitted to the observed rotational constant within 0.6%. The bond distance between atoms at zero bending is 1.287 A according to this model; this is noticeably larger than the average internuclear distance of 1.277 A for the vibrational ground state. The first order perturbation solutions for the vibrational energy levels, taking into account the effect of a quartic perturbation potential, closely match observed levels. For a square well potential model of C3, the effect of curvilinear motion in bending is similar to that found for the harmonic oscillator model, though the decreases in energy are about twice as large. In both models, the average energy decrease is relatively constant at approximately 10% over a wide range of vibrational quantum number.

  3. Dark Matter Search Results from the PICO-2L C3F8 Bubble Chamber

    SciTech Connect

    Amole, C.; Ardid, M.; Asner, David M.; Baxter, D.; Behnke, E.; Bhattacharjee, P. S.; Borsodi, H.; Bou-Cabo, M.; Brice, S. J.; Broemmelsiek, D.; Clark, K.; Collar, J. I.; Cooper, P. S.; Crisler, M.; Dahl, C. E.; Daley, S.; Das, Madhusmita; Debris, F.; Dhungana, N.; Farine, J.; Felis, I.; Filgas, R.; Fines-Neuschild, M.; Girard, Francoise; Giroux, G.; Hai, M.; Hall, Jeter C.; Harris, O.; Jackson, C. M.; Jin, M.; Krauss, C. B.; Lafreniere, M.; Laurin, M.; Lawson, I.; Levine, I.; Lippincott, W. H.; Mann, E.; Martin, J. P.; Maurya, D.; Mitra, Pitam; Neilson, R.; Noble, A. J.; Plante, A.; Podviianiuk, R. B.; Priya, S.; Robinson, A. E.; Ruschman, M.; Scallon, O.; Seth, S.; Sonnenschein, Andrew; Starinski, N.; Stekl, I.; Vazquez-Jauregui, E.; Wells, J.; Wichoski, U.; Zacek, V.; Zhang, J.

    2015-06-12

    New data are reported from the operation of a 2-liter C3F8 bubble chamber in the 2100 meter deep SNOLAB underground laboratory, with a total exposure of 211.5 kg-days at four different recoil energy thresholds ranging from 3.2 keV to 8.1 keV. These data show that C3F8 provides excellent electron recoil and alpha rejection capabilities at very low thresholds, including the rst observation of a dependence of acoustic signal on alpha energy. Twelve single nuclear recoil event candidates were observed during the run. The candidate events exhibit timing characteristics that are not consistent with the hypothesis of a uniform time distribution, and no evidence for a dark matter signal is claimed. These data provide the most sensitive direct detection constraints on WIMP-proton spin-dependent scattering to date, with signicant sensitivity at low WIMP masses for spin-independent WIMP-nucleon scattering.

  4. Intracellular location of NADP(+)-linked malic enzyme in C 3 plants.

    PubMed

    El-Shora, H M; Ap Rees, T

    1991-10-01

    The aim of this work was to determine the maximum catalytic activity and intracellular location of NADP(+)-linked malic enzyme (EC 1.1.1.40) in C3 plants. Appreciable activities, ranging from 80 to 712 nmol · (gFW)(-1) · min(-1), were found in a wide range of tissues (roots and leaves of Pisum sativum L., cotyledons of Cucurbit a pepo Alef., developing seeds of Brassica napus L., mesocarp of Persea americana Gaertn., and suspension cultures of Glycine max L.). Overall, activity showed a rough positive correlation with biosynthesis. Differential and density-gradient fractionation of extracts of the cotyledons of germinating marrow (C. pepo) and lysates of protoplasts of suspension cultures of G. showed that the enzyme had the same distribution as the plastid marker enzymes. It is suggested that in C3 plants NADP(+)-linked malic enzyme is confined to the plastids and involved in biosynthesis.

  5. C3-symmetric Ti(IV) triphenolate amino complexes as sulfoxidation catalysts with aqueous hydrogen peroxide.

    PubMed

    Mba, Myriam; Prins, Leonard J; Licini, Giulia

    2007-01-01

    [reaction: see text] The Ti(IV) complex 2c bearing a C3-symmetric triphenolate amine ligand is an air and moisture tolerant complex that efficiently catalyzes sulfoxidation reactions at room temperature without previous activation (catalyst loading down to 0.01%, TONs up to 8000, TOFs up to 1700 h-1, quantitative yields). Reactions were performed with aqueous hydrogen peroxide as oxidant, which adds value to the methodology from the environmental viewpoint.

  6. Complement split products c3a and c4a in chronic lyme disease.

    PubMed

    Stricker, R B; Savely, V R; Motanya, N C; Giclas, P C

    2009-01-01

    Complement split products C3a and C4a are reportedly elevated in patients with acute Lyme disease. We have now examined these immunologic markers in patients with chronic Lyme disease compared to appropriate disease controls. The study population consisted of 29 healthy controls, 445 patients with chronic Lyme disease, 11 patients with systemic lupus erythematosus (SLE) and six patients with AIDS. The Lyme disease patients were divided according to predominant musculoskeletal symptoms (324 patients) or predominant neurologic symptoms (121 patients). C3a and C4a levels were measured by radioimmunoassay. All patients with chronic Lyme disease and AIDS had normal C3a levels compared to controls, whereas patients with SLE had significantly increased levels of this marker. Patients with predominant musculoskeletal symptoms of Lyme disease and AIDS patients had significantly increased levels of C4a compared to either controls, patients with predominant neurologic symptoms of Lyme disease or SLE patients. Response to antibiotic therapy in chronic Lyme disease was associated with a significant decrease in the C4a level, whereas lack of response was associated with a significant increase in this marker. In contrast, AIDS patients had persistently increased C4a levels despite antiretroviral therapy. Lyme patients with positive single-photon emission computed tomographic (SPECT) scans had significantly lower C4a levels compared to Lyme patients with normal SPECT scan results. Patients with predominant musculoskeletal symptoms of Lyme disease have normal C3a and increased C4a levels. This pattern differs from the increase in both markers seen in acute Lyme disease, and C4a changes correlate with the response to therapy in chronic Lyme disease. C4a appears to be a valuable immunologic marker in patients with persistent symptoms of Lyme disease.

  7. A1BG and C3 are overexpressed in patients with cervical intraepithelial neoplasia III.

    PubMed

    Canales, Norma Angélica Galicia; Marina, Vicente Madrid; Castro, Jorge Salmerón; Jiménez, Alfredo Antúnez; Mendoza-Hernández, Guillermo; McCARRON, Elizabeth Langley; Roman, Margarita Bahena; Castro-Romero, Julieta Ivone

    2014-08-01

    The present study aimed to analyze sera proteins in females with cervical intraepithelial neoplasia, grade III (CIN III) and in healthy control females, in order to identify a potential biomarker which detects lesions that have a greater probability of cervical transformation. The present study investigated five sera samples from females who were Human Papilloma Virus (HPV) 16(+) and who had been histopathologically diagnosed with CIN III, as well as five sera samples from healthy control females who were HPV-negative. Protein separation was performed using two-dimensional (2D) gel electrophoresis and the proteins were stained with Colloidal Coommassie Blue. Quantitative analysis was performed using ImageMaster 2D Platinum 6.0 software. Peptide sequence identification was performed using a nano-LC ESIMS/MS system. The proteins with the highest Mascot score were validated using western blot analysis in an additional 55 sera samples from the control and CIN III groups. The eight highest score spots that were found to be overexpressed in the CIN III sera group were identified as α-1-B glycoprotein (A1BG), complement component 3 (C3), a pro-apolipoprotein, two apolipoproteins and three haptoglobins. Only A1BG and C3 were validated using western blot analysis, and the bands were compared between the two groups using densitometry analysis. The relative density of the bands of A1BG and C3 was found to be greater in all of the serum samples from the females with CIN III, compared with those of the individuals in the control group. In summary, the present study identified two proteins whose expression was elevated in females with CIN III, suggesting that they could be used as biomarkers for CIN III. However, further investigations are required in order to assess the expression of A1BG and C3 in different pre-malignant lesions.

  8. A1BG and C3 are overexpressed in patients with cervical intraepithelial neoplasia III

    PubMed Central

    CANALES, NORMA ANGÉLICA GALICIA; MARINA, VICENTE MADRID; CASTRO, JORGE SALMERÓN; JIMÉNEZ, ALFREDO ANTÚNEZ; MENDOZA-HERNÁNDEZ, GUILLERMO; McCARRON, ELIZABETH LANGLEY; ROMAN, MARGARITA BAHENA; CASTRO-ROMERO, JULIETA IVONE

    2014-01-01

    The present study aimed to analyze sera proteins in females with cervical intraepithelial neoplasia, grade III (CIN III) and in healthy control females, in order to identify a potential biomarker which detects lesions that have a greater probability of cervical transformation. The present study investigated five sera samples from females who were Human Papilloma Virus (HPV) 16+ and who had been histopathologically diagnosed with CIN III, as well as five sera samples from healthy control females who were HPV-negative. Protein separation was performed using two-dimensional (2D) gel electrophoresis and the proteins were stained with Colloidal Coommassie Blue. Quantitative analysis was performed using ImageMaster 2D Platinum 6.0 software. Peptide sequence identification was performed using a nano-LC ESIMS/MS system. The proteins with the highest Mascot score were validated using western blot analysis in an additional 55 sera samples from the control and CIN III groups. The eight highest score spots that were found to be overexpressed in the CIN III sera group were identified as α-1-B glycoprotein (A1BG), complement component 3 (C3), a pro-apolipoprotein, two apolipoproteins and three haptoglobins. Only A1BG and C3 were validated using western blot analysis, and the bands were compared between the two groups using densitometry analysis. The relative density of the bands of A1BG and C3 was found to be greater in all of the serum samples from the females with CIN III, compared with those of the individuals in the control group. In summary, the present study identified two proteins whose expression was elevated in females with CIN III, suggesting that they could be used as biomarkers for CIN III. However, further investigations are required in order to assess the expression of A1BG and C3 in different pre-malignant lesions. PMID:25009667

  9. Characterization of a C3 Deoxygenation Pathway Reveals a Key Branch Point in Aminoglycoside Biosynthesis.

    PubMed

    Lv, Meinan; Ji, Xinjian; Zhao, Junfeng; Li, Yongzhen; Zhang, Chen; Su, Li; Ding, Wei; Deng, Zixin; Yu, Yi; Zhang, Qi

    2016-05-25

    Apramycin is a clinically interesting aminoglycoside antibiotic (AGA) containing a highly unique bicyclic octose moiety, and this octose is deoxygenated at the C3 position. Although the biosynthetic pathways for most 2-deoxystreptamine-containing AGAs have been well characterized, the pathway for apramycin biosynthesis, including the C3 deoxygenation process, has long remained unknown. Here we report detailed investigation of apramycin biosynthesis by a series of genetic, biochemical and bioinformatical studies. We show that AprD4 is a novel radical S-adenosyl-l-methionine (SAM) enzyme, which uses a noncanonical CX3CX3C motif for binding of a [4Fe-4S] cluster and catalyzes the dehydration of paromamine, a pseudodisaccharide intermediate in apramycin biosynthesis. We also show that AprD3 is an NADPH-dependent reductase that catalyzes the reduction of the dehydrated product from AprD4-catalyzed reaction to generate lividamine, a C3' deoxygenated product of paromamine. AprD4 and AprD3 do not form a tight catalytic complex, as shown by protein complex immunoprecipitation and other assays. The AprD4/AprD3 enzyme system acts on different pseudodisaccharide substrates but does not catalyze the deoxygenation of oxyapramycin, an apramycin analogue containing a C3 hydroxyl group on the octose moiety, suggesting that oxyapramycin and apramycin are partitioned into two parallel pathways at an early biosynthetic stage. Functional dissection of the C6 dehydrogenase AprQ shows the crosstalk between different AGA biosynthetic gene clusters from the apramycin producer Streptomyces tenebrarius, and reveals the remarkable catalytic versatility of AprQ. Our study highlights the intriguing chemistry in apramycin biosynthesis and nature's ingenuity in combinatorial biosynthesis of natural products.

  10. Collaborative Chronic Care Networks (C3Ns) to transform chronic illness care.

    PubMed

    Margolis, Peter A; Peterson, Laura E; Seid, Michael

    2013-06-01

    Despite significant gains by pediatric collaborative improvement networks, the overall US system of chronic illness care does not work well. A new paradigm is needed: a Collaborative Chronic Care Network (C3N). A C3N is a network-based production system that harnesses the collective intelligence of patients, clinicians, and researchers and distributes the production of knowledge, information, and know-how over large groups of people, dramatically accelerating the discovery process. A C3N is a platform of "operating systems" on which interconnected processes and interventions are designed, tested, and implemented. The social operating system is facilitated by community building, engaging all stakeholders and their expertise, and providing multiple ways to participate. Standard progress measures and a robust information technology infrastructure enable the technical operating system to reduce unwanted variation and adopt advances more rapidly. A structured approach to innovation design provides a scientific operating system or "laboratory" for what works and how to make it work. Data support testing and research on multiple levels: comparative effectiveness research for populations, evaluating care delivery processes at the care center level, and N-of-1 trials and other methods to select the best treatment of individual patient circumstances. Methods to reduce transactional costs to participate include a Federated IRB Model in which centers rely on a protocol approved at 1 central institutional review board and a "commons framework" for organizational copyright and intellectual property concerns. A fully realized C3N represents a discontinuous leap to a self-developing learning health system capable of producing a qualitatively different approach to improving health. PMID:23729764

  11. Analysis of apolipoprotein A5, C3 and plasma triglyceride concentrations in genetically engineered mice

    SciTech Connect

    Baroukh, Nadine; Bauge, Eric; Akiyama, Jennifer; Chang, Jessie; Afzal, Veena; Fruchart, Jean-Charles; Rubin, Edward M.; Fruchart, Jamila; Pennacchio, Len A.

    2004-03-11

    To address the relationship between the apolipoprotein A5 and C3 genes, we generated independent lines of mice that either over-expressed or completely lacked both genes. We report both lines display normal triglyceride concentrations compared to over-expression or deletion of either gene alone. Together, these data support that APOA5 and APOC3 independently influence plasma triglyceride concentrations but in an opposing manner.

  12. Characterization of a C3 Deoxygenation Pathway Reveals a Key Branch Point in Aminoglycoside Biosynthesis.

    PubMed

    Lv, Meinan; Ji, Xinjian; Zhao, Junfeng; Li, Yongzhen; Zhang, Chen; Su, Li; Ding, Wei; Deng, Zixin; Yu, Yi; Zhang, Qi

    2016-05-25

    Apramycin is a clinically interesting aminoglycoside antibiotic (AGA) containing a highly unique bicyclic octose moiety, and this octose is deoxygenated at the C3 position. Although the biosynthetic pathways for most 2-deoxystreptamine-containing AGAs have been well characterized, the pathway for apramycin biosynthesis, including the C3 deoxygenation process, has long remained unknown. Here we report detailed investigation of apramycin biosynthesis by a series of genetic, biochemical and bioinformatical studies. We show that AprD4 is a novel radical S-adenosyl-l-methionine (SAM) enzyme, which uses a noncanonical CX3CX3C motif for binding of a [4Fe-4S] cluster and catalyzes the dehydration of paromamine, a pseudodisaccharide intermediate in apramycin biosynthesis. We also show that AprD3 is an NADPH-dependent reductase that catalyzes the reduction of the dehydrated product from AprD4-catalyzed reaction to generate lividamine, a C3' deoxygenated product of paromamine. AprD4 and AprD3 do not form a tight catalytic complex, as shown by protein complex immunoprecipitation and other assays. The AprD4/AprD3 enzyme system acts on different pseudodisaccharide substrates but does not catalyze the deoxygenation of oxyapramycin, an apramycin analogue containing a C3 hydroxyl group on the octose moiety, suggesting that oxyapramycin and apramycin are partitioned into two parallel pathways at an early biosynthetic stage. Functional dissection of the C6 dehydrogenase AprQ shows the crosstalk between different AGA biosynthetic gene clusters from the apramycin producer Streptomyces tenebrarius, and reveals the remarkable catalytic versatility of AprQ. Our study highlights the intriguing chemistry in apramycin biosynthesis and nature's ingenuity in combinatorial biosynthesis of natural products. PMID:27120352

  13. Dynamic Entangled Porous Framework for Hydrocarbon (C2-C3) Storage, CO2 Capture, and Separation.

    PubMed

    Sikdar, Nivedita; Bonakala, Satyanarayana; Haldar, Ritesh; Balasubramanian, Sundaram; Maji, Tapas Kumar

    2016-04-18

    Storage and separation of small (C1-C3) hydrocarbons are of great significance as these are alternative energy resources and also can be used as raw materials for many industrially important materials. Selective capture of greenhouse gas, CO2 from CH4 is important to improve the quality of natural gas. Among the available porous materials, MOFs with permanent porosity are the most suitable to serve these purposes. Herein, a two-fold entangled dynamic framework {[Zn2 (bdc)2 (bpNDI)]⋅4DMF}n with pore surface carved with polar functional groups and aromatic π clouds is exploited for selective capture of CO2 , C2, and C3 hydrocarbons at ambient condition. The framework shows stepwise CO2 and C2 H2 uptake at 195 K but type I profiles are observed at 298 K. The IAST selectivity of CO2 over CH4 is the highest (598 at 298 K) among the MOFs without open metal sites reported till date. It also shows high selectivity for C2 H2 , C2 H4 , C2 H6 , and C3 H8 over CH4 at 298 K. DFT calculations reveal that aromatic π surface and the polar imide (RNC=O) functional groups are the primary adsorption sites for adsorption. Furthermore, breakthrough column experiments showed CO2 /CH4 C2 H6 /CH4 and CO2 /N2 separation capability at ambient condition.

  14. C-H Bond Activation by Early Transition Metal Carbide Cluster Anion MoC3 (-).

    PubMed

    Li, Zi-Yu; Hu, Lianrui; Liu, Qing-Yu; Ning, Chuan-Gang; Chen, Hui; He, Sheng-Gui; Yao, Jiannian

    2015-12-01

    Although early transition metal (ETM) carbides can activate CH bonds in condensed-phase systems, the electronic-level mechanism is unclear. Atomic clusters are ideal model systems for understanding the mechanisms of bond activation. For the first time, CH activation of a simple alkane (ethane) by an ETM carbide cluster anion (MoC3 (-) ) under thermal-collision conditions has been identified by using high-resolution mass spectrometry, photoelectron imaging spectroscopy, and high-level quantum chemical calculations. Dehydrogenation and ethene elimination were observed in the reaction of MoC3 (-) with C2 H6 . The CH activation follows a mechanism of oxidative addition that is much more favorable in the carbon-stabilized low-spin ground electronic state than in the high-spin excited state. The reaction efficiency between the MoC3 (-) anion and C2 H6 is low (0.23±0.05) %. A comparison between the anionic and a highly efficient cationic reaction system (Pt(+) +C2 H6 ) was made. It turned out that the potential-energy surfaces for the entrance channels of the anionic and cationic reaction systems can be very different. PMID:26490554

  15. Nitrogen Starvation Induced Oxidative Stress in an Oil-Producing Green Alga Chlorella sorokiniana C3

    PubMed Central

    He, Chen-Liu; Wang, Qiang

    2013-01-01

    Microalgal lipid is one of the most promising feedstocks for biodiesel production. Chlorella appears to be a particularly good option, and nitrogen (N) starvation is an efficient environmental pressure used to increase lipid accumulation in Chlorella cells. The effects of N starvation of an oil-producing wild microalga, Chlorella sorokiniana C3, on lipid accumulation were investigated using thin layer chromatography (TLC), confocal laser scanning microscopy (CLSM) and flow cytometry (FCM). The results showed that N starvation resulted in lipid accumulation in C. sorokiniana C3 cells, oil droplet (OD) formation and significant lipid accumulation in cells were detected after 2 d and 8 d of N starvation, respectively. During OD formation, reduced photosynthetic rate, respiration rate and photochemistry efficiency accompanied by increased damage to PSII were observed, demonstrated by chlorophyll (Chl) fluorescence, 77K fluorescence and oxygen evolution tests. In the mean time the rate of cyclic electron transportation increased correspondingly to produce more ATP for triacylglycerols (TAGs) synthesis. And 0.5 d was found to be the turning point for the early stress response and acclimation of cells to N starvation. Increased level of membrane peroxidation was also observed during OD formation, and superoxide dismutase (SOD), peroxide dismutase (POD) and catalase (CAT) enzyme activity assays suggested impaired reactive oxygen species (ROS) scavenging ability. Significant neutral lipid accumulation was also observed by artificial oxidative stress induced by H2O2 treatment. These results suggested coupled neutral lipid accumulation and oxidative stress during N starvation in C. sorokiniana C3. PMID:23874918

  16. Laboratory detection of the C3N an C4H free radicals

    NASA Technical Reports Server (NTRS)

    Gottlieb, C. A.; Gottlieb, E. W.; Thaddeus, P.; Kawamura, H.

    1983-01-01

    The millimeter-wave spectra of the linear carbon chain free radicals C3N and C4H, first identified in IRC + 10216 and hitherto observed only in a few astronomical sources, have been detected with a Zeeman-modulated spectrometer in laboratory glow discharges through low pressure flowing mixtures of N2 + HC3N and He + HCCH, respectively. Four successive rotational transitions between 168 and 198 GHz have been measured for C3N, and five rotational transitions between 143 and 200 GHz for C4H; each is a well-resolved spin doublet owing to the unpaired electron present in both species. Precise values for the rotational, centrifugal distortion, and spin doubling constants have been obtained, which, with hyperfine constants derived from observations of the lower rotational transitions in the astronomical source TMC 1, allow all the rotational transitions of C3N and C4H at frequencies less than 300 GHz to be calculated to an absolute accuracy exceeding 1 ppm.

  17. Mechanical properties and chemical bonding characteristics of Cr7C3 type multicomponent carbides

    NASA Astrophysics Data System (ADS)

    Xiao, B.; Feng, J.; Zhou, C. T.; Jiang, Y. H.; Zhou, R.

    2011-01-01

    The first principles calculations based on density functional theory are performed to investigate the mechanical properties and chemical bonding features of several Cr7C3 type multicomponent carbides (Fe16Cr12C12, Fe12Cr12W4C12, Fe12Cr12Mo4C12, Fe12Cr12W4C8B4, and Fe12Cr12Mo4C8B4). The full set elastic constants are calculated using stress-strain method. The Voigt-Reuss-Hill approximation is used to evaluate the mechanical moduli. The mechanical anisotropy is characterized by calculating several different anisotropic indexes and factors, such as universal anisotropic index (AU), shear anisotropic factors (A1, A2, and A3), and percent anisotropy (AB and AG). The surface constructions of bulk and Young's moduli are illustrated to indicate the mechanical anisotropy. The obtained results indicate that the presence of B could deteriorate the mechanical moduli of (Fe,Cr)7C3 phase in Cr cast iron slightly. On the other hand, the chemical stability of (Fe,Cr)7C3 carbides is improved due to chemical bonding modifications through doping with B. These conclusions are in agreement with experimental results.

  18. Dark matter limits from a 2L C3F8 filled bubble chamber

    NASA Astrophysics Data System (ADS)

    Robinson, Alan Edward

    The PICO-2L C3F8 bubble chamber search for Weakly Interacting Massive Particle (WIMP) dark matter was operated in the SNOLAB underground laboratory at the same location as the previous CF3I filled COUPP-4kg detector. Neutron calibrations using photoneutron sources in C3F8 and CF3I filled calibration bubble chambers were performed to verify the sensitivity of these target fluids to dark matter scattering. This data was combined with similar measurements using a low-energy neutron beam at the University of Montreal and in situ calibrations of the PICO-2L and COUPP-4kg detectors. C3F 8 provides much greater sensitivity to WIMP-proton scattering than CF 3I in bubble chamber detectors. PICO-2L searched for dark matter recoils with energy thresholds below 10 keV. Radiopurity assays of detector materials were performed and the expected neutron recoil background was evaluated to be 1.6 +0.3-0.9 single bubble events during the 211.5 kg-day exposure. Twelve single bubble dark matter candidate events were observed. These events were not uniformly distributed in time, and were likely caused by particulates in the active volume. Despite this background, PICO-2L sets a world-leading upper limit to the WIMP-proton spin dependent scattering cross-section.

  19. Structural Domain Switching by Magnetic Fields in RAl3C3 (R = Rare Earth)

    NASA Astrophysics Data System (ADS)

    Matsumura, Takeshi; Hayashi, Yuya; Takai, Shun; Otsubo, Toru; Matsuda, Saori; Ochiai, Akira

    2015-11-01

    Hexagonal-to-orthorhombic structural transitions in RAl3C3 have been studied by X-ray diffraction for R = Yb, Tm, Er, Dy, and Lu. We report how orthorhombic domains are controlled by adjusting external magnetic fields. It is shown that orthorhombic domains in RAl3C3 can be aligned by the field when the R ion is magnetic. It is also shown that a single-domain state can be switched to another single-domain state by the field even in paramagnetic states with small induced moments. For R = Lu, however, it was not possible to change the multidomain state by a field of up to 70 kOe. We discuss that domain selection and switching are caused by magnetic anisotropies in the orthorhombic phase of RAl3C3. We also propose an idea to explain the field-induced antiferromagnetism revealed by Khalyavin et al. [Phys. Rev. B 87, 220406(R) (2013)].

  20. High efficiency photocatalysis for pollutant degradation with MoS2/C3N4 heterostructures.

    PubMed

    Li, Qian; Zhang, Ning; Yang, Yong; Wang, Guozhong; Ng, Dickon H L

    2014-07-29

    Porous graphitic carbon nitride was synthesized by controllable thermal polymerization of urea in air. Their textural, electrical, and optical properties were tuned by varying the heating rate. The presence of proper residual oxygen in carbon nitride matrix had enhanced light absorption and inhibited the recombination of charge carriers. Furthermore, the MoS2 nanosheets were coupled into the carbon nitride to form MoS2/C3N4 heterostructures via a facile ultrasonic chemical method. The optimized MoS2/C3N4 heterostructure with 0.05 wt % MoS2 showed a reaction rate constant as high as 0.301 min(-1), which was 3.6 times that of bare carbon nitride. As analyzed by SEM, TEM, UV-vis absorption, PL and photoelectrochemical measurements, intimate contact interface, extended light response range, enhanced separation speed of charge carriers, and high photocurrent density upon MoS2 coupling led to the photocatalytic promotion of the MoS2/C3N4 heterostructures. In this architecture, MoS2 served as electron trapper to extend the lifetime of separated electron-hole pairs. Meanwhile, the accumulated holes on the surface of carbon nitride oxidized the organic dye directly, which was a predominant process in the photodegradation of organic pollutants in water treatment. The promotional mechanisms and principles reported here would have great significance in heterogeneous photocatalysis.

  1. Dark Matter Limits From a 2L C3F8 Filled Bubble Chamber

    SciTech Connect

    Robinson, Alan Edward

    2015-12-01

    The PICO-2L C3F8 bubble chamber search forWeakly Interacting Massive Particle (WIMP) dark matter was operated in the SNOLAB underground laboratory at the same location as the previous CF3I lled COUPP-4kg detector. Neutron calibrations using photoneutron sources in C3F8 and CF3I lled calibration bubble chambers were performed to verify the sensitivity of these target uids to dark matter scattering. This data was combined with similar measurements using a low-energy neutron beam at the University of Montreal and in situ calibrations of the PICO-2L and COUPP-4kg detectors. C3F8 provides much greater sensitivity to WIMP-proton scattering than CF3I in bubble chamber detectors. PICO-2L searched for dark matter recoils with energy thresholds below 10 keV. Radiopurity assays of detector materials were performed and the expected neutron recoil background was evaluated to be 1.6+0:3

  2. CFH haplotypes and ARMS2, C2, C3, and CFB alleles show association with susceptibility to age-related macular degeneration in Mexicans

    PubMed Central

    Zenteno, Juan Carlos; Fernández-López, Juan Carlos; Rodríguez-Corona, Ulises; Falfán-Valencia, Ramcés; Sebastian, Leticia; Morales, Fabiola; Ochoa-Contreras, Daniel; Carnevale, Alessandra; Silva-Zolezzi, Irma

    2014-01-01

    Purpose To evaluate the contribution of genetic variants of complement factor H (CFH), complement component 2 and 3 (C2 and C3), complement factor B (CFB), and age-related maculopathy susceptibility 2 (ARMS2) to age-related macular degeneration (AMD) risk in the Mexican Mestizo population. Methods Analysis included 282 unrelated Mexican patients with advanced AMD, 205 healthy controls, and 280 population controls. Stereoscopic fundus images were graded on the Clinical Age-Related Maculopathy System (CARMS). We designed a resequencing strategy using primers with M13 adaptor for the 23 exons of the CFH gene in a subgroup of 96 individuals clinically evaluated: 48 AMD cases and 48 age- and sex-matched healthy controls. Single nucleotide polymorphisms (SNPs) in C3 (Arg80Gly and Pro292Leu), C2 (rs547154), CFB (Leu9His), and ARMS2 (Ala69Ser) were genotyped in all patients, healthy and population controls using TaqMan assay. Results All evaluated individuals were Mexican Mestizos, and their genetic ancestry was validated using 224 ancestry informative markers and calculating Fst values. The CFH resequencing revealed 19 SNPs and a common variant in the intron 2 splice acceptor site; three CFH haplotypes inferred from individual genotypes, showed significant differences between cases and controls. The risk alleles in C3 (rs1047286, odds ratio [OR]=2.48, 95% confidence interval [CI]=1.64–3.75, p=1.59E-05; rs2230199, OR=2.15, 95% CI=1.48–3.13, p=6.28E-05) and in ARMS2 (rs10490924, OR=3.09, 95% CI=2.48–3.86, p=5.42E-23) were strongly associated with risk of AMD. The protective effect of alleles in C2 (rs547154) and CFB (rs4151667) showed a trend but was not significantly associated after correction for multiple testing. Conclusions Our results show that ARMS2 and C3 are major contributors to advanced AMD in Mexican patients, while the contributions of CFH, C2, and CFB are minor to those of other populations, reveling significant ethnic differences in minor allele

  3. Preferential Nucleation during Polymorphic Transformations

    PubMed Central

    Sharma, H.; Sietsma, J.; Offerman, S. E.

    2016-01-01

    Polymorphism is the ability of a solid material to exist in more than one phase or crystal structure. Polymorphism may occur in metals, alloys, ceramics, minerals, polymers, and pharmaceutical substances. Unresolved are the conditions for preferential nucleation during polymorphic transformations in which structural relationships or special crystallographic orientation relationships (OR’s) form between the nucleus and surrounding matrix grains. We measured in-situ and simultaneously the nucleation rates of grains that have zero, one, two, three and four special OR’s with the surrounding parent grains. These experiments show a trend in which the activation energy for nucleation becomes smaller – and therefore nucleation more probable - with increasing number of special OR’s. These insights contribute to steering the processing of polymorphic materials with tailored properties, since preferential nucleation affects which crystal structure forms, the average grain size and texture of the material, and thereby - to a large extent - the final properties of the material. PMID:27484579

  4. Preferential Nucleation during Polymorphic Transformations

    NASA Astrophysics Data System (ADS)

    Sharma, H.; Sietsma, J.; Offerman, S. E.

    2016-08-01

    Polymorphism is the ability of a solid material to exist in more than one phase or crystal structure. Polymorphism may occur in metals, alloys, ceramics, minerals, polymers, and pharmaceutical substances. Unresolved are the conditions for preferential nucleation during polymorphic transformations in which structural relationships or special crystallographic orientation relationships (OR’s) form between the nucleus and surrounding matrix grains. We measured in-situ and simultaneously the nucleation rates of grains that have zero, one, two, three and four special OR’s with the surrounding parent grains. These experiments show a trend in which the activation energy for nucleation becomes smaller – and therefore nucleation more probable - with increasing number of special OR’s. These insights contribute to steering the processing of polymorphic materials with tailored properties, since preferential nucleation affects which crystal structure forms, the average grain size and texture of the material, and thereby - to a large extent - the final properties of the material.

  5. Preferential Nucleation during Polymorphic Transformations.

    PubMed

    Sharma, H; Sietsma, J; Offerman, S E

    2016-08-03

    Polymorphism is the ability of a solid material to exist in more than one phase or crystal structure. Polymorphism may occur in metals, alloys, ceramics, minerals, polymers, and pharmaceutical substances. Unresolved are the conditions for preferential nucleation during polymorphic transformations in which structural relationships or special crystallographic orientation relationships (OR's) form between the nucleus and surrounding matrix grains. We measured in-situ and simultaneously the nucleation rates of grains that have zero, one, two, three and four special OR's with the surrounding parent grains. These experiments show a trend in which the activation energy for nucleation becomes smaller - and therefore nucleation more probable - with increasing number of special OR's. These insights contribute to steering the processing of polymorphic materials with tailored properties, since preferential nucleation affects which crystal structure forms, the average grain size and texture of the material, and thereby - to a large extent - the final properties of the material.

  6. Preferential Nucleation during Polymorphic Transformations.

    PubMed

    Sharma, H; Sietsma, J; Offerman, S E

    2016-01-01

    Polymorphism is the ability of a solid material to exist in more than one phase or crystal structure. Polymorphism may occur in metals, alloys, ceramics, minerals, polymers, and pharmaceutical substances. Unresolved are the conditions for preferential nucleation during polymorphic transformations in which structural relationships or special crystallographic orientation relationships (OR's) form between the nucleus and surrounding matrix grains. We measured in-situ and simultaneously the nucleation rates of grains that have zero, one, two, three and four special OR's with the surrounding parent grains. These experiments show a trend in which the activation energy for nucleation becomes smaller - and therefore nucleation more probable - with increasing number of special OR's. These insights contribute to steering the processing of polymorphic materials with tailored properties, since preferential nucleation affects which crystal structure forms, the average grain size and texture of the material, and thereby - to a large extent - the final properties of the material. PMID:27484579

  7. Potential of knowledge discovery using workflows implemented in the C3Grid

    NASA Astrophysics Data System (ADS)

    Engel, Thomas; Fink, Andreas; Ulbrich, Uwe; Schartner, Thomas; Dobler, Andreas; Fritzsch, Bernadette; Hiller, Wolfgang; Bräuer, Benny

    2013-04-01

    With the increasing number of climate simulations, reanalyses and observations, new infrastructures to search and analyse distributed data are necessary. In recent years, the Grid architecture became an important technology to fulfill these demands. For the German project "Collaborative Climate Community Data and Processing Grid" (C3Grid) computer scientists and meteorologists developed a system that offers its users a webinterface to search and download climate data and use implemented analysis tools (called workflows) to further investigate them. In this contribution, two workflows that are implemented in the C3Grid architecture are presented: the Cyclone Tracking (CT) and Stormtrack workflow. They shall serve as an example on how to perform numerous investigations on midlatitude winterstorms on a large amount of analysis and climate model data without having an insight into the data source, program code and a low-to-moderate understanding of the theortical background. CT is based on the work of Murray and Simmonds (1991) to identify and track local minima in the mean sea level pressure (MSLP) field of the selected dataset. Adjustable thresholds for the curvature of the isobars as well as the minimum lifetime of a cyclone allow the distinction of weak subtropical heat low systems and stronger midlatitude cyclones e.g. in the Northern Atlantic. The user gets the resulting track data including statistics about the track density, average central pressure, average central curvature, cyclogenesis and cyclolysis as well as pre-built visualizations of these results. Stormtrack calculates the 2.5-6 day bandpassfiltered standard deviation of the geopotential height on a selected pressure level. Although this workflow needs much less computational effort compared to CT it shows structures that are in good agreement with the track density of the CT workflow. To what extent changes in the mid-level tropospheric storm track are reflected in trough density and intensity

  8. Glyphosate Resistance of C3 and C4 Weeds under Rising Atmospheric CO2.

    PubMed

    Fernando, Nimesha; Manalil, Sudheesh; Florentine, Singarayer K; Chauhan, Bhagirath S; Seneweera, Saman

    2016-01-01

    The present paper reviews current knowledge on how changes of plant metabolism under elevated CO2 concentrations (e[CO2]) can affect the development of the glyphosate resistance of C3 and C4 weeds. Among the chemical herbicides, glyphosate, which is a non-selective and post-emergence herbicide, is currently the most widely used herbicide in global agriculture. As a consequence, glyphosate resistant weeds, particularly in major field crops, are a widespread problem and are becoming a significant challenge to future global food production. Of particular interest here it is known that the biochemical processes involved in photosynthetic pathways of C3 and C4 plants are different, which may have relevance to their competitive development under changing environmental conditions. It has already been shown that plant anatomical, morphological, and physiological changes under e[CO2] can be different, based on (i) the plant's functional group, (ii) the available soil nutrients, and (iii) the governing water status. In this respect, C3 species are likely to have a major developmental advantage under a CO2 rich atmosphere, by being able to capitalize on the overall stimulatory effect of e[CO2]. For example, many tropical weed grass species fix CO2 from the atmosphere via the C4 photosynthetic pathway, which is a complex anatomical and biochemical variant of the C3 pathway. Thus, based on our current knowledge of CO2 fixing, it would appear obvious that the development of a glyphosate-resistant mechanism would be easier under an e[CO2] in C3 weeds which have a simpler photosynthetic pathway, than for C4 weeds. However, notwithstanding this logical argument, a better understanding of the biochemical, genetic, and molecular measures by which plants develop glyphosate resistance and how e[CO2] affects these measures will be important before attempting to innovate sustainable technology to manage the glyphosate-resistant evolution of weeds under e[CO2]. Such information will be of

  9. Glyphosate Resistance of C3 and C4 Weeds under Rising Atmospheric CO2.

    PubMed

    Fernando, Nimesha; Manalil, Sudheesh; Florentine, Singarayer K; Chauhan, Bhagirath S; Seneweera, Saman

    2016-01-01

    The present paper reviews current knowledge on how changes of plant metabolism under elevated CO2 concentrations (e[CO2]) can affect the development of the glyphosate resistance of C3 and C4 weeds. Among the chemical herbicides, glyphosate, which is a non-selective and post-emergence herbicide, is currently the most widely used herbicide in global agriculture. As a consequence, glyphosate resistant weeds, particularly in major field crops, are a widespread problem and are becoming a significant challenge to future global food production. Of particular interest here it is known that the biochemical processes involved in photosynthetic pathways of C3 and C4 plants are different, which may have relevance to their competitive development under changing environmental conditions. It has already been shown that plant anatomical, morphological, and physiological changes under e[CO2] can be different, based on (i) the plant's functional group, (ii) the available soil nutrients, and (iii) the governing water status. In this respect, C3 species are likely to have a major developmental advantage under a CO2 rich atmosphere, by being able to capitalize on the overall stimulatory effect of e[CO2]. For example, many tropical weed grass species fix CO2 from the atmosphere via the C4 photosynthetic pathway, which is a complex anatomical and biochemical variant of the C3 pathway. Thus, based on our current knowledge of CO2 fixing, it would appear obvious that the development of a glyphosate-resistant mechanism would be easier under an e[CO2] in C3 weeds which have a simpler photosynthetic pathway, than for C4 weeds. However, notwithstanding this logical argument, a better understanding of the biochemical, genetic, and molecular measures by which plants develop glyphosate resistance and how e[CO2] affects these measures will be important before attempting to innovate sustainable technology to manage the glyphosate-resistant evolution of weeds under e[CO2]. Such information will be of

  10. Glyphosate Resistance of C3 and C4 Weeds under Rising Atmospheric CO2

    PubMed Central

    Fernando, Nimesha; Manalil, Sudheesh; Florentine, Singarayer K.; Chauhan, Bhagirath S.; Seneweera, Saman

    2016-01-01

    The present paper reviews current knowledge on how changes of plant metabolism under elevated CO2 concentrations (e[CO2]) can affect the development of the glyphosate resistance of C3 and C4 weeds. Among the chemical herbicides, glyphosate, which is a non-selective and post-emergence herbicide, is currently the most widely used herbicide in global agriculture. As a consequence, glyphosate resistant weeds, particularly in major field crops, are a widespread problem and are becoming a significant challenge to future global food production. Of particular interest here it is known that the biochemical processes involved in photosynthetic pathways of C3 and C4 plants are different, which may have relevance to their competitive development under changing environmental conditions. It has already been shown that plant anatomical, morphological, and physiological changes under e[CO2] can be different, based on (i) the plant’s functional group, (ii) the available soil nutrients, and (iii) the governing water status. In this respect, C3 species are likely to have a major developmental advantage under a CO2 rich atmosphere, by being able to capitalize on the overall stimulatory effect of e[CO2]. For example, many tropical weed grass species fix CO2 from the atmosphere via the C4 photosynthetic pathway, which is a complex anatomical and biochemical variant of the C3 pathway. Thus, based on our current knowledge of CO2 fixing, it would appear obvious that the development of a glyphosate-resistant mechanism would be easier under an e[CO2] in C3 weeds which have a simpler photosynthetic pathway, than for C4 weeds. However, notwithstanding this logical argument, a better understanding of the biochemical, genetic, and molecular measures by which plants develop glyphosate resistance and how e[CO2] affects these measures will be important before attempting to innovate sustainable technology to manage the glyphosate-resistant evolution of weeds under e[CO2]. Such information will be

  11. Photochemical Modeling of the Distribution of C3H8 in the Atmosphere of Saturn

    NASA Astrophysics Data System (ADS)

    Edgington, S. G.; Simon-Miller, A.; Jennings, D.; Bjoraker, G.; Romani, P.; Achterberg, R.; Orton, G.; Flasar, M.; Cassini CIRS Team

    2005-08-01

    Cassini's Composite Infrared Spectrometer (CIRS) has measured the abundance of C2H2 and C3H8 (Propane) at several latitudes in the Southern hemisphere. An increase of radiance with latitude towards the pole has been observed, possibly implying a corresponding increase of C3H8. In an effort explain the observed distribution of both species, it is important to model the creation, destruction, and transport of these chemical species. Furthermore, since both molecules have overlapping absorption features in the same spectral region near 748 cm-1, such modeling will aid in refining derived abundances and separating temperature effects. The photochemistry model used in Edgington et al. (1998, 1999, 2000) to model simultaneously hydrocarbons, ammonia, and phosphine is updated and expanded to include paths relevant to the creation of C3H8. Destruction occurs through photolysis, while transport would tend to spread C3H8 from its source regions. With a series of exercises in 1- and 2- dimensions, we explore the extent to which photolysis, vertical, and/or meridional transport impacts the distribution of C2H2 and C3H8 with latitude. Thermal profiles derived from CIRS observations versus latitude are used as they have an impact on numerous reaction rates. We then compare these results with abundances derived from observations taken with the CIRS instrument. Edgington, S.G., West, R.A., Friedson, A.J., Atreya, S.K., 2000. A 2-D photochemical model with meridional circulation. Bull. American. Astron. Soc., 32, 1013. Edgington, S.G., S.K. Atreya, L.M. Trafton, J.J. Caldwell, R.F. Beebe, A.A. Simon, and R.A. West, 1999. Ammonia and eddy mixing variations in the southern hemisphere of Jupiter from HST Faint Object Spectrograph Observations. Icarus, 142, 342-357. Edgington, S.G., S.K. Atreya, L.M. Trafton, J.J. Caldwell, R.F. Beebe, A.A. Simon, R.A. West, and C. Barnet, 1998. On the latitude variation of ammonia, acetylene, and phosphine altitude profiles on Jupiter from HST Faint

  12. Genetic polymorphisms and disease prevention.

    PubMed

    Mahoney, Martin C

    2007-06-15

    Building upon the resources of traditional epidemiology, molecular epidemiology has extended our understanding that disease risk varies based not only upon acquired factors (e.g., exposures, behaviors, demographics), but also as a function of inherited factors (e.g., genetic polymorphisms). Individual susceptibility to cancer is influenced by polymorphisms in phase I enzymes (e.g., activation), phase 2 enzymes (e.g., detoxification), defects in the repair of DNA damage and other cancer susceptibility genes. Because tobacco use and nutrition represent behaviors/exposures which account for a significant number of cancer cases and deaths, these two factors are used to illustrate the relationship between genetic polymorphisms and disease prevention. Susceptibility to the health risks of smoking appears to be influenced by genetic factors that impact initiation, dependence, and nicotine metabolism. Nutrient metabolism also involves polymorphic enzyme pathways and gene-nutrient interactions may influence cancer risk. While the discipline of molecular epidemiology continues to face methodologic challenges related to the need to study large numbers of subjects, current knowledge can be applied to prevention activities. Genetic polymorphisms, and other molecular markers, can be used to develop clinical prevention studies targeted to unique subsets of persons at the highest risk of developing disease. Knowledge about the relationships between polymorphisms and disease outcomes can also be used for reinforcing healthy lifestyles, motivating positive behavior changes, helping to target medical therapy, and aiding in better focusing surveillance activities. PMID:17252563

  13. The frequency of cytochrome P450 2E1 polymorphisms in Black South Africans.

    PubMed

    Chelule, Paul K; Pegoraro, Rosemary J; Gqaleni, Nceba; Dutton, Michael F

    2006-01-01

    Polymorphisms in the promoter region of the Cytochrome P4502E1 (CYP2E1) gene reportedly modify the metabolic activity of CYP2E1 enzyme, and have been associated with increased susceptibility to squamous cell carcinoma (SCC) of the oesophagus in high prevalence areas such as China. To assess the frequency of these polymorphisms in Black South Africans, a population with a high incidence of oesophageal SCC, this study examined genomic DNA from 331 subjects for restriction fragment length polymorphisms in the CYP2E1 (RsaI and PstI digestion). The frequency of the CYP2E1 c1/c1 and c1/c3 genotypes was 95% and 5% respectively. The frequency of the CYP2E1 allele distribution was found to be markedly different between Chinese and South African populations; hence it is important to place racial differences into consideration when proposing allelic variants as genetic markers for cancer. PMID:17264406

  14. Reduced graphene oxide wrapped Cu2O supported on C3N4: An efficient visible light responsive semiconductor photocatalyst

    NASA Astrophysics Data System (ADS)

    Ganesh Babu, S.; Vinoth, R.; Surya Narayana, P.; Bahnemann, Detlef; Neppolian, B.

    2015-10-01

    Herein, Cu2O spheres were prepared and encapsulated with reduced graphene oxide (rGO). The Cu2O-rGO-C3N4 composite covered the whole solar spectrum with significant absorption intensity. rGO wrapped Cu2O loading caused a red shift in the absorption with respect to considering the absorption of bare C3N4. The photoluminescence study confirms that rGO exploited as an electron transport layer at the interface of Cu2O and C3N4 heterojunction. Utmost, ˜2 fold synergistic effect was achieved with Cu2O-rGO-C3N4 for the photocatalytic reduction of 4-nitrophenol to 4-aminophenol in comparison with Cu2O-rGO and C3N4. The Cu2O-rGO-C3N4 photocatalyst was reused for four times without loss in its activity.

  15. New polymorphous computing fabric.

    SciTech Connect

    Wolinski, C.; Gokhale, M.; McCabe, K. P.

    2002-01-01

    This paper introduces a new polymorphous computing Fabric well suited to DSP and Image Processing and describes its implementation on a Configurable System on a Chip (CSOC). The architecture is highly parameterized and enables customization of the synthesized Fabric to achieve high performance for a specific class of application. For this reason it can be considered to be a generic model for hardware accelerator synthesis from a high level specification. Another important innovation is the Fabric uses a global memory concept, which gives the host processor random access to all the variables and instructions on the Fabric. The Fabric supports different computing models including MIMD, SPMD and systolic flow and permits dynamic reconfiguration. We present a specific implementation of a bank of FIR filters on a Fabric composed of 52 cells on the Altera Excalibur ARM running at 33 MHz. The theoretical performance of this Fabric is 1.8 GMACh. For the FIR application we obtain 1.6 GMAC/s real performance. Some automatic tools have been developed like the tool to provide a host access utility and assembler.

  16. Preparation of water-dispersible porous g-C3N4 with improved photocatalytic activity by chemical oxidation.

    PubMed

    Li, Hui-Jun; Sun, Bo-Wen; Sui, Li; Qian, Dong-Jin; Chen, Meng

    2015-02-01

    Hydrophilic treatment of bulk graphene-like carbon nitride (g-C3N4) for future applications has aroused extensive interest, due to its enhanced specific surface area and unusual electronic properties. Herein, water-dispersible g-C3N4 with a porous structure can be obtained by chemical oxidation of bulk g-C3N4 with K2Cr2O7-H2SO4. Acid oxidation results in the production of hydroxyl and carboxyl groups on its basal plane and the formation of a porous structure of g-C3N4 at the same time. The porous g-C3N4 appears as networks with tens of micrometers in width and possesses a high specific surface area of 235.2 m(2) g(-1). The final concentration of porous g-C3N4 can be up to 3 mg mL(-1). Compared with bulk g-C3N4, the as-obtained porous g-C3N4 exhibits excellent water dispersion stability and shows great superiority in photoinduced charge carrier separation and transfer. The photocatalytic activities of porous g-C3N4 towards degradation of organic pollutants are much higher than those of the bulk due to the larger band gap (by 0.2 eV) and specific surface areas.

  17. Use of Single-Layer g-C3N4/Ag Hybrids for Surface-Enhanced Raman Scattering (SERS)

    NASA Astrophysics Data System (ADS)

    Jiang, Jizhou; Zou, Jing; Wee, Andrew Thye Shen; Zhang, Wenjing

    2016-09-01

    Surface-enhanced Raman scattering (SERS) substrates with high activity and stability are desirable for SERS sensing. Here, we report a new single atomic layer graphitic-C3N4 (S-g-C3N4) and Ag nanoparticles (NPs) hybrid as high-performance SERS substrates. The SERS mechanism of the highly stable S-g-C3N4/Ag substrates was systematically investigated by a combination of experiments and theoretical calculations. From the results of XPS and Raman spectroscopies, it was found that there was a strong interaction between S-g-C3N4 and Ag NPs, which facilitates the uniform distribution of Ag NPs over the edges and surfaces of S-g-C3N4 nanosheets, and induces a charge transfer from S-g-C3N4 to the oxidizing agent through the silver surface, ultimately protecting Ag NPs from oxidation. Based on the theoretical calculations, we found that the net surface charge of the Ag atoms on the S-g-C3N4/Ag substrates was positive and the Ag NPs presented high dispersibility, suggesting that the Ag atoms on the S-g-C3N4/Ag substrates were not likely to be oxidized, thereby ensuring the high stability of the S-g-C3N4/Ag substrate. An understanding of the stability mechanism in this system can be helpful for developing other effective SERS substrates with long-term stability.

  18. The Steroidogenic Enzyme AKR1C3 Regulates Stability of the Ubiquitin Ligase Siah2 in Prostate Cancer Cells.

    PubMed

    Fan, Lingling; Peng, Guihong; Hussain, Arif; Fazli, Ladan; Guns, Emma; Gleave, Martin; Qi, Jianfei

    2015-08-21

    Re-activation of androgen receptor (AR) activity is the main driver for development of castration-resistant prostate cancer. We previously reported that the ubiquitin ligase Siah2 enhanced AR transcriptional activity and prostate cancer cell growth. Among the genes we found to be regulated by Siah2 was AKR1C3, which encodes a key androgen biosynthetic enzyme implicated in castration-resistant prostate cancer development. Here, we found that Siah2 inhibition in CWR22Rv1 prostate cancer cells decreased AKR1C3 expression as well as intracellular androgen levels, concomitant with inhibition of cell growth in vitro and in orthotopic prostate tumors. Re-expression of either wild-type or catalytically inactive forms of AKR1C3 partially rescued AR activity and growth defects in Siah2 knockdown cells, suggesting a nonenzymatic role for AKR1C3 in these outcomes. Unexpectedly, AKR1C3 re-expression in Siah2 knockdown cells elevated Siah2 protein levels, whereas AKR1C3 knockdown had the opposite effect. We further found that AKR1C3 can bind Siah2 and inhibit its self-ubiquitination and degradation, thereby increasing Siah2 protein levels. We observed parallel expression of Siah2 and AKR1C3 in human prostate cancer tissues. Collectively, our findings identify a new role for AKR1C3 in regulating Siah2 stability and thus enhancing Siah2-dependent regulation of AR activity in prostate cancer cells.

  19. Use of Single-Layer g-C3N4/Ag Hybrids for Surface-Enhanced Raman Scattering (SERS)

    PubMed Central

    Jiang, Jizhou; Zou, Jing; Wee, Andrew Thye Shen; Zhang, Wenjing

    2016-01-01

    Surface-enhanced Raman scattering (SERS) substrates with high activity and stability are desirable for SERS sensing. Here, we report a new single atomic layer graphitic-C3N4 (S-g-C3N4) and Ag nanoparticles (NPs) hybrid as high-performance SERS substrates. The SERS mechanism of the highly stable S-g-C3N4/Ag substrates was systematically investigated by a combination of experiments and theoretical calculations. From the results of XPS and Raman spectroscopies, it was found that there was a strong interaction between S-g-C3N4 and Ag NPs, which facilitates the uniform distribution of Ag NPs over the edges and surfaces of S-g-C3N4 nanosheets, and induces a charge transfer from S-g-C3N4 to the oxidizing agent through the silver surface, ultimately protecting Ag NPs from oxidation. Based on the theoretical calculations, we found that the net surface charge of the Ag atoms on the S-g-C3N4/Ag substrates was positive and the Ag NPs presented high dispersibility, suggesting that the Ag atoms on the S-g-C3N4/Ag substrates were not likely to be oxidized, thereby ensuring the high stability of the S-g-C3N4/Ag substrate. An understanding of the stability mechanism in this system can be helpful for developing other effective SERS substrates with long-term stability. PMID:27687573

  20. Dual interaction of factor H with C3d and glycosaminoglycans in host-nonhost discrimination by complement.

    PubMed

    Kajander, Tommi; Lehtinen, Markus J; Hyvärinen, Satu; Bhattacharjee, Arnab; Leung, Elisa; Isenman, David E; Meri, Seppo; Goldman, Adrian; Jokiranta, T Sakari

    2011-02-15

    The alternative pathway of complement is important in innate immunity, attacking not only microbes but all unprotected biological surfaces through powerful amplification. It is unresolved how host and nonhost surfaces are distinguished at the molecular level, but key components are domains 19-20 of the complement regulator factor H (FH), which interact with host (i.e., nonactivator surface glycosaminoglycans or sialic acids) and the C3d part of C3b. Our structure of the FH19-20:C3d complex at 2.3-Å resolution shows that FH19-20 has two distinct binding sites, FH19 and FH20, for C3b. We show simultaneous binding of FH19 to C3b and FH20 to nonactivator surface glycosaminoglycans, and we show that both of these interactions are necessary for full binding of FH to C3b on nonactivator surfaces (i.e., for target discrimination). We also show that C3d could replace glycosaminoglycan binding to FH20, thus providing a feedback control for preventing excess C3b deposition and complement amplification. This explains the molecular basis of atypical hemolytic uremic syndrome, where mutations on the binding interfaces between FH19-20 and C3d or between FH20 and glycosaminoglycans lead to complement attack against host surfaces.

  1. JPSS CGS C3S McMurdo Multimission Communications System

    NASA Astrophysics Data System (ADS)

    Higgins, C.; Urbano, J.; Jamilkowski, M. L.

    2011-12-01

    NOAA's next-generation civilian environmental satellite system, the Joint Polar Satellite System (JPSS) developed by NASA, will supply the afternoon orbit & ground system of the restructured NPOESS program. JPSS will replace NOAA's current POES system and ground processing part of both POES & DoD's Defense Weather Satellite System (DWSS). JPSS sensors will collect meteorological, oceanographic, climatological & solar-geophysical data. The command & data distribution part of the JPSS Common Ground System (CGS) is the Command, Control & Communications Segment (C3S), developed by Raytheon Intelligence & Information Systems. C3S manages the overall JPSS & DWSS missions from control & status of the space & ground assets to ensuring timely delivery of high-quality data to the Interface Data Processing Segment (IDPS). Key to C3S' data delivery system are 15 globally-distributed ground receptors developed by Raytheon Company which will collect up to 5 times the environmental data about 4 times faster than current polar-orbiting weather satellites. Then these data will be rapidly forwarded to weather centrals via the global fiber optic network for processing/production of data records for use in environmental prediction models. McMurdo Station, Antarctica is a major receptor site due to its high latitude. With the NSF, C3S completed the upgrade & expansion of their existing off-continent satellite communications (SATCOM) link with 60 Mbps of bandwidth outbound and 20 Mbps inbound to missions using McMurdo. C3S completed the 1st big milestone in 2008 increasjng bandwidth of 3 Mbps to/from Antarctica to 10 Mbps both ways. Raytheon's C3S also upgraded network infrastructure at McMurdo Station & Belrose Earth Station, Australia SATCOM sites. This provides routing support for several missions, plus expansion capabilities to support future missions at McMurdo. The upgrade completed in Dec 2010 to prepare for use of McMurdo Station to support new downlink capabilities, called the

  2. Carbon Isotope Discrimination in C3 Land Plants is Independent of Atmospheric PCO2

    NASA Astrophysics Data System (ADS)

    Kohn, M. J.

    2015-12-01

    The δ13C of terrestrial C3 plant tissues and soil organic matter is important for understanding the carbon cycle, inferring past climatic and ecological conditions, and predicting responses of vegetation to future climate change. Plant δ13C depends on the δ13C of atmospheric CO2 and mean annual precipitation (MAP), but an unresolved decades-long debate centers on whether terrestrial C3 plant δ13C responds to pCO2. Here, the pCO2-dependence of C3 land plant δ13C was tested using isotopic records from low- and high-pCO2 times spanning historical through Eocene data. Historical data do not resolve a clear pCO2-effect (-1.2±1.0 to 0.59±0.34‰/100 ppmv), and organic carbon records of the Pleistocene-Holocene transition implicate changes in MAP and ecosystems, rather than pCO2, as the major driver of δ13C changes. Fossil collagen and tooth enamel data constrain pCO2-effects most tightly to -0.03±0.13 and -0.03±0.24‰/100 ppmv between 200 and 700 ppmv. Combining all constraints yields a preferred value of 0.0±0.2‰/100 ppmv (2 s.e.), i.e. there is effectively no pCO2 effect. Recent models of pCO2-dependence imply unrealistic MAP for Cenozoic records.

  3. Photoelectrochemical Conversion from Graphitic C3N4 Quantum Dot Decorated Semiconductor Nanowires.

    PubMed

    An, Tiance; Tang, Jing; Zhang, Yueyu; Quan, Yingzhou; Gong, Xingao; Al-Enizi, Abdullah M; Elzatahry, Ahmed A; Zhang, Lijuan; Zheng, Gengfeng

    2016-05-25

    Despite the recent progress of developing graphitic carbon nitride (g-C3N4) as a metal-free photocatalyst, the synthesis of nanostructured g-C3N4 has still remained a complicated and time-consuming approach from its bulk powder, which substantially limits its photoelectrochemical (PEC) applications as well as the potential to form composites with other semiconductors. Different from the labor-intensive methods used before, such as exfoliation or assistant templates, herein, we developed a facile method to synthesize graphitic C3N4 quantum dots (g-CNQDs) directly grown on TiO2 nanowire arrays via a one-step quasi-chemical vapor deposition (CVD) process in a homemade system. The as-synthesized g-CNQDs uniformly covered over the surface of TiO2 nanowires and exhibited attractive photoluminescence (PL) properties. In addition, compared to pristine TiO2, the heterojunction of g-CNQD-decorated TiO2 nanowires showed a substantially enhanced PEC photocurrent density of 3.40 mA/cm(2) at 0 V of applied potential vs Ag/AgCl under simulated solar light (300 mW/cm(2)) and excellent stability with ∼82% of the photocurrent retained after over 10 h of continuous testing, attributed to the quantum and sensitization effects of g-CNQDs. Density functional theory calculations were further carried out to illustrate the synergistic effect of TiO2 and g-CNQD. Our method suggests that a variety of g-CNQD-based composites with other semiconductor nanowires can be synthesized for energy applications. PMID:27149607

  4. C3 vanadium(V) amine triphenolate complexes: vanadium haloperoxidase structural and functional models.

    PubMed

    Mba, Miriam; Pontini, Marta; Lovat, Silvia; Zonta, Cristiano; Bernardinelli, Gerald; Kündig, Peter E; Licini, Giulia

    2008-10-01

    The C 3 vanadium(V) amine triphenolate complex 1f has been characterized as a structural and functional model of vanadium haloperoxidases. The complex catalyzes efficiently sulfoxidations at room temperature using hydrogen peroxide as the terminal oxidant, yielding the corresponding sulfoxides in quantitative yields and high selectivities (catalyst loading down to 0.01%, TONs up to 9900, and TOFs up to 8000 h (-1)) as well as bromination of 1,3,5-trimethoxybenzene (catalyst loading down to 0.05%, TONs up to 1260, and TOFs up to 220 h (-1)).

  5. Optical and electrical characterization of C3H6O/Ar glow discharge

    NASA Astrophysics Data System (ADS)

    Villalobos, S.; Castillo, F.; Flores, O.; Reyes, P. G.; Martínez, H.

    2015-03-01

    A low pressure glow discharge apparatus was used to produce a glow discharge of C3H6O/Ar mixture at a total pressure of 2.0 Torr. The emission spectra were measured in the wavelength range of 200 to 1100 nm. The principal species observed were Ar I, C6H4O, C6H5, CHO, CH3O, CO2, CO, H2O, and H2. The electron temperature and ion density have been measured using a double Langmuir probe, and the electron temperature and ion density were found in the order of 10 eV and 1010 cm-3.

  6. Future directions of C3 research at DARPA (Defense Advanced Research Projects Agency)

    NASA Astrophysics Data System (ADS)

    Perry, D. G.; Dahmann, J. S.

    Research into C3 related problems is a major effort of the Information Science and Technology Office of the Defense Advanced Research Projects Agency. The major thrusts of projects are in the area of future, high-risk efforts, often resulting in the development of a conceptual model or prototype. Some of these prototypes are then further developed to provide an infrastructure for future research. The programs can be divided into two groups: base technology research programs and testbed programs. The testbeds provide a focus for the technology programs.

  7. Octupolar (C3 and S4) Symmetric Cyclized Indole Derivatives: Syntheses, Structures, and NLO Properties.

    PubMed

    Wang, Lei; Fang, Qi; Lu, Qing; Zhang, Shao-jun; Jin, Ying-ying; Liu, Zhi-qiang

    2015-09-01

    Several cyclized indole derivatives have been synthesized, and their structures been determined. The C3-symmetric single-chiral N-phenyltriindole (Tr-Ph3) crystallized in the P1 space group, and the S4-symmetric saddle-like tetraindole (TTr) crystallized in the I4̅ space group. The Tr-Ph3 and TTr crystals exhibit remarkable powder SHG intensities 5 and 11 times that of KH2PO4 (KDP), respectively. TTr is a useful octupolar core to build S4-symmetric molecules and crystals for second-NLO materials.

  8. Optical characterization of perturbed sites and C3i sites in rare earth doped oxide crystals

    NASA Astrophysics Data System (ADS)

    Reinemer, Gregoy Donald

    Energies, linewidths, and line strengths for some intrinsic and perturbed site transitions of seven different rare-earth ions doped into Y3Al 5O12 were measured as a function of concentration using visible and infrared absorption. Nearest and next-nearest neighbor ion pair transitions were characterized by their concentration dependence, and an analysis of Pr 3+ and Nd3+ pairs showed that those ions are distributed randomly in the lattice. For all transitions studied, the intrinsic D2 site and pair site transitions accounted for 92%--95% of the total line strength; the remaining 5%--8% was assigned to perturbed site transitions. No significant dependence of perturbed site line strength on ionic radius was observed. The nominally equal perturbed site line strength for all transitions studied implied that oscillator strengths for intrinsic and perturbed sites were similar. The perturbed sites appear to be a normal property of the Y3Al 5O12 lattice. To further investigate the nature of the perturbed sites, experiments were done showing that Er3+ occupies a site in Er3+ :Y3Al5O12 with a threefold axis along <111> that is consistent with occupation of the octahedral Al3+ site with C3i symmetry. Allowed magnetic dipole transitions at 1.5 microns were identified in the 4I15/2(1)→ 4I13/2 absorption spectrum using site selective fluorescence. Angle dependent Zeeman experiments on these transitions confirmed that they are from a site with a threefold axis along <111>. Using optical nutation experiments, the number density for Er 3+ C3i sites in 1.0 at.% Er3+:Y3Al 5O12 was determined to be (5 +/- 2) x 10 17 Er3+/cm3. Since Er3+ has nearly the same ionic radius as Y3+, the occupation of these same sites by Y3+ was deduced to be 0.6% +/- 0.3%. Assuming each Y3+ C3i site perturbs 12 D2 sites, the fractional line strength for perturbed sites would be 5% +/- 2%. Similar experiments on 0.05 at.% Er3+:Y2O 3 characterized C3i site Er3+ 4I 15/2 and 4I13/2 crystal field levels and g

  9. Sc2@C3v(8)-C82 vs. Sc2C2@C3v(8)-C82: drastic effect of C2 capture on the redox properties of scandium metallofullerenes.

    PubMed

    Kurihara, Hiroki; Lu, Xing; Iiduka, Yuko; Mizorogi, Naomi; Slanina, Zdenek; Tsuchiya, Takahiro; Nagase, Shigeru; Akasaka, Takeshi

    2012-01-30

    We describe the first example of scandium dimetallofullerenes, Sc(2)@C(3v)(8)-C(82), which has the same cage as the previously assigned scandium carbide cluster fullerene Sc(2)C(2)@C(3v)(8)-C(82) but they exhibit distinctly different electronic configurations and electronic behaviours, confirming the drastic influence of the internal C(2) unit.

  10. An ab initio study on the formation of interstellar tricarbon isomers l-C 3(X 1Σg+) and c-C 3(X 3A 2')

    NASA Astrophysics Data System (ADS)

    Mebel, A. M.; Kaiser, R. I.

    2002-07-01

    Ab initio CCSD(T)/6-311+G(3df,2p)//B3LYP/6-311G(d,p) calculations have been performed to investigate potential energy surfaces of the C( 3Pj)+ C2H( X2Σ +) and CH( X2Π Ω)+ C2( X1Σ g+) reactions. Both reactions are shown to proceed by barrierless additions of C( 3Pj) and CH to C 2H and C 2, respectively, to produce the c-C 3H(X 2B 1) and l- C3H( X2Π Ω) intermediates with high exothermicities, which can rearrange to each other via a barrier of 27 kcal/mol. l-C 3H fragments into l- C3( X1Σ g+)+ H( 2S1/2) (the major product), and c-C 3H dissociates to c- C3( X3A2')+ H( 2S1/2) (the minor product), both without an exit barrier. The reactions represent facile neutral-neutral pathways to produce tricarbon isomers in interstellar environments.

  11. Structural Polymorphism in Amyloids

    PubMed Central

    Jones, Eric M.; Wu, Bo; Surewicz, Krystyna; Nadaud, Philippe S.; Helmus, Jonathan J.; Chen, Shugui; Jaroniec, Christopher P.; Surewicz, Witold K.

    2011-01-01

    The C-terminally-truncated human prion protein variant Y145Stop (or PrP23–144), associated with a familial prion disease, provides a valuable model for studying the fundamental properties of protein amyloids. In previous solid-state NMR experiments, we established that the β-sheet core of the PrP23–144 amyloid is composed of two β-strand regions encompassing residues ∼113–125 and ∼130–140. The former segment contains a highly conserved hydrophobic palindrome sequence, 113AGAAAAGA120, which has been considered essential to PrP conformational conversion. Here, we examine the role of this segment in fibrillization of PrP23–144 using a deletion variant, Δ113–120 PrP23–144, in which the palindrome sequence is missing. Surprisingly, we find that deletion of the palindrome sequence affects neither the amyloidogenicity nor the polymerization kinetics of PrP23–144, although it does alter amyloid conformation and morphology. Using two-dimensional and three-dimensional solid-state NMR methods, we find that Δ113–120 PrP23–144 fibrils contain an altered β-core extended N-terminally to residue ∼106, encompassing residues not present in the core of wild-type PrP23–144 fibrils. The C-terminal β-strand of the core, however, is similar in both fibril types. Collectively, these data indicate that amyloid cores of PrP23–144 variants contain “essential” (i.e. nucleation-determining) and “nonessential” regions, with the latter being “movable” in amino acid sequence space. These findings reveal an intriguing new mechanism for structural polymorphism in amyloids and suggest a potential means for modulating the physicochemical properties of amyloid fibrils without compromising their polymerization characteristics. PMID:22002245

  12. Effects of variations in the APOA1/C3/A4/A5 gene cluster on different parameters of postprandial lipid metabolism in healthy young men.

    PubMed

    Delgado-Lista, Javier; Perez-Jimenez, Francisco; Ruano, Juan; Perez-Martinez, Pablo; Fuentes, Francisco; Criado-Garcia, Juan; Parnell, Laurence D; Garcia-Rios, Antonio; Ordovas, Jose M; Lopez-Miranda, Jose

    2010-01-01

    The APOA1/C3/A4/A5 gene cluster encodes important regulators of fasting lipids, but the majority of lipid metabolism takes place in the postprandial state and knowledge about gene regulation in this state is scarce. With the aim of characterizing possible regulators of lipid metabolism, we studied the effects of nine single nucleotide polymorphisms (SNPs) during postprandial lipid metabolism. Eighty-eight healthy young men were genotyped for APOA1 -2630 (rs613808), APOA1 -2803 (rs2727784), APOA1 -3012 (rs11216158), APOC3 -640 (rs2542052), APOC3 -2886 (rs2542051), APOC3 G34G (rs4520), APOA4 N147S (rs5104), APOA4 T29T (rs5092), and A4A5_inter (rs1263177) and were fed a saturated fatty acid-rich meal (1g fat/kg of weight with 60% fat, 15% protein and 25% carbohydrate). Serial blood samples were extracted for 11 h after the meal. Total cholesterol and fractions [HDL-cholesterol, LDL-cholesterol, trifacylglycerols (TGs) in plasma, TG-rich lipoproteins (TRLs) (large TRLs and small TRLs), apolipoprotein A-I and apolipoprotein B] were determined. APOA1 -2803 homozygotes for the minor allele and A4A5_inter carriers showed a limited degree of postprandial lipemia. Carriers of the rare alleles of APOA4 N147S and APOA4 T29T had lower APOA1 plasma concentration during this state. APOC3 -640 was associated with altered TG kinetics but not its magnitude. We have identified new associations between SNPs in the APOA1/C3/A4/A5 gene cluster and altered postprandial lipid metabolism.

  13. Effect of Carbide Ceramic Zone on Wear Resistance of the (Fe,Cr)7C3/Fe Surface Gradient Composite

    NASA Astrophysics Data System (ADS)

    Ye, Fangxia; Xu, Yunhua; Hojamberdiev, Mirabbos; Lai, Yujun; Wang, Chong; Wang, Xin

    2015-08-01

    In this work, we report on the influence of microstructure and mechanical properties of the (Fe,Cr)7C3 ceramic zone on wear resistance of the (Fe,Cr)7C3/Fe surface gradient composite fabricated by in situ synthesis method followed by a post-heat treatment at 1100 °C for 20 h in argon atmosphere. The phase composition, microstructure, nanoindentation hardness, elastic modulus, fracture toughness, and relative wear resistance of the (Fe,Cr)7C3/Fe surface gradient composite were investigated by means of x-ray diffraction, scanning electron microscopy, nanoindentation tester, and wear resistance testing instrument, respectively. The XRD results showed that (Fe,Cr)7C3 is the predominant crystalline phases in the fabricated composite. The volume fraction of the (Fe,Cr)7C3 particulates formed has a gradient distribution from the surface to the iron matrix, and the microstructure also changes significantly. The (Fe,Cr)7C3 bulk ceramic zone with the volume fraction of about 100% and the (Fe,Cr)7C3 dense ceramic zone with the volume fraction of about 90% were synthesized on the upper surface of the (Fe,Cr)7C3/Fe surface gradient composite, respectively. The average nanoindentation hardness and elastic modulus of the (Fe,Cr)7C3 bulk ceramic zone of the composite were determined to be 12.711 and 256.054 GPa, respectively. The fracture toughness of the (Fe,Cr)7C3 bulk ceramic zone is in the range of 2.06-4.19 MPa m1/2, and its relative wear resistance is about 56 times higher than that of the iron matrix. The (Fe,Cr)7C3 dense ceramic zone with rod-like, secondary (Fe,Cr)7C3 particulates was formed at the bottom of the (Fe,Cr)7C3 bulk ceramic zone. Rod-like, secondary (Fe,Cr)7C3 particulates are dense and grew in the direction of the iron substrate, providing higher wear resistance to the composite. The wear mechanisms of the (Fe,Cr)7C3 bulk and dense ceramic zones are considered to be microcutting, microcracking, and spalling pit.

  14. Contact activation of C3 enables tethering between activated platelets and polymorphonuclear leukocytes via CD11b/CD18

    PubMed Central

    Hamad, Osama A.; Mitroulis, Ioannis; Fromell, Karin; Kozarcanin, Huda; Chavakis, Triantafyllos; Ricklin, Daniel; Lambris, John D.; Ekdahl, Kristina N.; Nilsson, Bo

    2016-01-01

    Summary Complement component C3 has a potential role in thrombotic pathologies. It is transformed, without proteolytic cleavage, into C3(H2O) upon binding to the surface of activated platelets. We hypothesise that C3(H2O) bound to activated platelets and to platelet-derived microparticles (PMPs) contributes to platelet-PMN complex (PPC) formation and to the binding of PMPs to PMNs. PAR-1 activation of platelets in human whole blood from normal individuals induced the formation of CD16+/CD42a+ PPC. The complement inhibitor compstatin and a C5a receptor antagonist inhibited PPC formation by 50 %, while monoclonal antibodies to C3(H2O) or anti-CD11b inhibited PPC formation by 75–100 %. Using plasma protein-depleted blood and blood from a C3-deficient patient, we corroborated the dependence on C3, obtaining similar results after reconstitution with purified C3. By analogy with platelets, PMPs isolated from human serum were found to expose C3(H2O) and bind to PMNs. This interaction was also blocked by the anti-C3(H2O) and anti-CD11b monoclonal antibodies, indicating that C3(H2O) and CD11b are involved in tethering PMPs to PMNs. We confirmed the direct interaction between C3(H2O) and CD11b by quartz crystal microbalance analysis using purified native C3 and recombinant CD11b/CD18 and by flow cytometry using PMP and recombinant CD11b. Transfectants expressing CD11b/CD18 were also shown to specifically adhere to surface-bound C3(H2O). We have identified contact-activated C3(H2O) as a novel ligand for CD11b/CD18 that mediates PPC formation and the binding of PMPs to PMNs. Given the various roles of C3 in thrombotic reactions, this finding is likely to have important pathophysiological implications. PMID:26293614

  15. Contact activation of C3 enables tethering between activated platelets and polymorphonuclear leukocytes via CD11b/CD18.

    PubMed

    Hamad, Osama A; Mitroulis, Ioannis; Fromell, Karin; Kozarcanin, Huda; Chavakis, Triantafyllos; Ricklin, Daniel; Lambris, John D; Ekdahl, Kristina N; Nilsson, Bo

    2015-11-25

    Complement component C3 has a potential role in thrombotic pathologies. It is transformed, without proteolytic cleavage, into C3(H2O) upon binding to the surface of activated platelets. We hypothesise that C3(H2O) bound to activated platelets and to platelet-derived microparticles (PMPs) contributes to platelet-PMN complex (PPC) formation and to the binding of PMPs to PMNs. PAR-1 activation of platelets in human whole blood from normal individuals induced the formation of CD16+/CD42a+ PPC. The complement inhibitor compstatin and a C5a receptor antagonist inhibited PPC formation by 50 %, while monoclonal antibodies to C3(H2O) or anti-CD11b inhibited PPC formation by 75-100 %. Using plasma protein-depleted blood and blood from a C3-deficient patient, we corroborated the dependence on C3, obtaining similar results after reconstitution with purified C3. By analogy with platelets, PMPs isolated from human serum were found to expose C3(H2O) and bind to PMNs. This interaction was also blocked by the anti-C3(H2O) and anti-CD11b monoclonal antibodies, indicating that C3(H2O) and CD11b are involved in tethering PMPs to PMNs. We confirmed the direct interaction between C3(H2O) and CD11b by quartz crystal microbalance analysis using purified native C3 and recombinant CD11b/CD18 and by flow cytometry using PMP and recombinant CD11b. Transfectants expressing CD11b/CD18 were also shown to specifically adhere to surface-bound C3(H2O). We have identified contact-activated C3(H2O) as a novel ligand for CD11b/CD18 that mediates PPC formation and the binding of PMPs to PMNs. Given the various roles of C3 in thrombotic reactions, this finding is likely to have important pathophysiological implications. PMID:26293614

  16. Identification of OprF as a Complement Component C3 Binding Acceptor Molecule on the Surface of Pseudomonas aeruginosa

    PubMed Central

    Mishra, Meenu; Ressler, Adam; Schlesinger, Larry S.

    2015-01-01

    Pseudomonas aeruginosa is a versatile opportunistic pathogen that can cause devastating persistent infections. Complement is a highly conserved pathway of the innate immune system, and its role in the first line of defense against pathogens is widely appreciated. One of the earliest events in the complement cascade is the conversion of C3 to C3a and C3b, the latter typically binds to one or more acceptor molecules on the pathogen surface. We previously demonstrated that complement C3b binding acceptors exist on the P. aeruginosa surface. In the current study, we utilized either C3 polyclonal or C3b monoclonal antibodies in a far-Western technique followed by mass spectroscopy to identify the C3b acceptor molecule(s) on the P. aeruginosa surface. Our data provide evidence that OprF (an outer membrane porin, highly conserved in the Pseudomonadaceae) binds C3b. An oprF-deficient P. aeruginosa strain exhibits reduced C3 deposition compared to the wild type. We observed reduced internalization of oprF-deficient bacteria by neutrophils after opsonization compared with wild-type P. aeruginosa. Heterologous expression of OprF significantly enhanced C3b binding and increased serum-mediated bactericidal effects in complement-susceptible Escherichia coli. Furthermore, the predicted secondary structure of the C-terminal, surface-exposed region of OprF has high structural identity to the OmpA domain of several other Gram-negative bacteria, one of which is known to bind C3b. Therefore, these findings provide new insights into the biology of complement interactions with P. aeruginosa and other Gram-negative bacteria. PMID:25964476

  17. C3a Increases VEGF and Decreases PEDF mRNA Levels in Human Retinal Pigment Epithelial Cells

    PubMed Central

    Long, Qin; Cao, Xiaoguang; Bian, Ailing

    2016-01-01

    Complement activation, specifically complement 3 (C3) activation and C3a generation, contributes to an imbalance between angiogenic stimulation by vascular endothelial growth factor (VEGF) and angiogenic inhibition by pigment epithelial derived factor (PEDF), leading to pathological angiogenesis. This study aimed to investigate the effects of C3a and small interfering RNA (siRNA) targeting C3 on the levels of VEGF and PEDF mRNAs in human retinal pigment epithelial (RPE) cells. ARPE-19 cells were cultured in the presence of exogenous C3a at 0.1 μM and 0.3 μM C3a for 24, 48, and 72 hours. 0.1 pmol/μL duplexes of siRNA targeting C3 were applied for C3a inhibition by transfecting ARPE-19 cells for 48 hours. RT-PCR was performed to examine the level of VEGF and PEDF mRNA. A random siRNA duplex was set for control siRNA. Results demonstrated that exogenous C3a significantly upregulated VEGF and downregulated PEDF mRNA levels in cultured ARPE-19 cells, and siRNA targeting C3 transfection reversed the above changes, significantly reducing VEGF and enhancing PEDF mRNAs level in ARPE-19 cells compared to the control. The present data provided evidence that reducing C3 activation can decreases VEGF and increase PEDF mRNA level in RPE and may serve as a potential therapy in pathological angiogenesis. PMID:27747237

  18. Comparative phenotypic assessment of cardiac pathology, physiology, and gene expression in C3H/HeJ, C57BL/6J, and B6C3F1/J mice.

    PubMed

    Auerbach, Scott S; Thomas, Reuben; Shah, Ruchir; Xu, Hong; Vallant, Molly K; Nyska, Abraham; Dunnick, June K

    2010-10-01

    Human cardiomyopathies often lead to heart failure, a major cause of morbidity and mortality in industrialized nations. Described here is a phenotypic characterization of cardiac function and genome-wide expression from C3H/HeJ, C57BL/6J, and B6C3F1/J male mice. Histopathologic analysis identified a low-grade background cardiomyopathy (murine progressive cardiomyopathy) in eight of nine male C3H/HeJ mice (age nine to ten weeks), but not in male C57BL/6J and in only of ten male B6C3F1/J mice. The C3H/HeJ mouse had an increased heart rate and a shorter RR interval compared to the B6C3F1/J and C57BL/6J mice. Cardiac genomic studies indicated the B6C3F1/J mice exhibited an intermediate gene expression phenotype relative to the 2 parental strains. Disease-centric enrichment analysis indicated a number of cardiomyopathy-associated genes were induced in B6C3F1/J and C3H/HeJ mice, including Myh7, My14, and Lmna and also indicated differential expression of genes associated with metabolic (e.g., Pdk2) and hypoxic stress (e.g. Hif1a). A novel coexpression and integrated pathway network analysis indicated Prkaa2, Pdk2, Rhoj, and Sgcb are likely to play a central role in the pathophysiology of murine progressive cardiomyopathy in C3H/HeJ mice. Our studies indicate that genetically determined baseline differences in cardiac phenotype have the potential to influence the results of cardiotoxicity studies. PMID:21037199

  19. Molecular-beam experiments for photodissociation of propenal at 157 nm and quantum-chemical calculations for migration and elimination of hydrogen atoms in systems C3H4O and C3H3O

    NASA Astrophysics Data System (ADS)

    Chin, Chih-Hao; Chaudhuri, Chanchal; Lee, Shih-Huang

    2011-07-01

    We investigated the dynamics of photodissociation of propenal (acrolein, CH2CHCHO) at 157 nm in a molecular beam and of migration and elimination of hydrogen atoms in systems C3H4O and C3H3O using quantum-chemical calculations. Compared with the previous results of photodissociation of propenal at 193 nm, the major difference is that the C3H3O fragment present at the 193-nm photolysis disappears at the 157-nm photolysis whereas the C3H2O fragment absent at 193 nm appears at 157 nm. Optimized structures and harmonic vibrational frequencies of molecular species with gross formula C3H2-4O were computed at the level of B3LYP/6-311G(d,p) and total energies of those molecules at optimized structures were computed at the level of CCSD(T)/6-311+G(3df,2p). Based on the calculated potential-energy surfaces, we deduce that the C3H3O fragment observed in the photolysis of propenal at 193 nm is probably CHCCHOH (2A″) and/or CH2CCOH (2A″) produced from an intermediate hydroxyl propadiene (CH2CCHOH) following isomerization. Adiabatic and vertical ionization potentials of eight isomers of C3H3O and two isomers of C3H2O were calculated; CHCCHOH (2A″) and CH2CCOH (2A″) have ionization potentials in good agreement with the experimental value of ˜7.4 eV. We also deduce that all the nascent C3H3O fragments from the photolysis of propenal at 157 nm spontaneously decompose mainly to C2H3 + CO and C3H2O + H because of the large excitation energy. This work provides profound insight into the dynamics of migration and elimination of hydrogen atoms of propenal optically excited in the vacuum-ultraviolet region.

  20. Dark Matter Search Results from the PICO-2L C3F8 Bubble Chamber.

    PubMed

    Amole, C; Ardid, M; Asner, D M; Baxter, D; Behnke, E; Bhattacharjee, P; Borsodi, H; Bou-Cabo, M; Brice, S J; Broemmelsiek, D; Clark, K; Collar, J I; Cooper, P S; Crisler, M; Dahl, C E; Daley, S; Das, M; Debris, F; Dhungana, N; Farine, J; Felis, I; Filgas, R; Fines-Neuschild, M; Girard, F; Giroux, G; Hai, M; Hall, J; Harris, O; Jackson, C M; Jin, M; Krauss, C B; Lafrenière, M; Laurin, M; Lawson, I; Levine, I; Lippincott, W H; Mann, E; Martin, J P; Maurya, D; Mitra, P; Neilson, R; Noble, A J; Plante, A; Podviianiuk, R B; Priya, S; Robinson, A E; Ruschman, M; Scallon, O; Seth, S; Sonnenschein, A; Starinski, N; Štekl, I; Vázquez-Jáuregui, E; Wells, J; Wichoski, U; Zacek, V; Zhang, J

    2015-06-12

    New data are reported from the operation of a 2 liter C3F8 bubble chamber in the SNOLAB underground laboratory, with a total exposure of 211.5 kg days at four different energy thresholds below 10 keV. These data show that C3F8 provides excellent electron-recoil and alpha rejection capabilities at very low thresholds. The chamber exhibits an electron-recoil sensitivity of <3.5×10(-10) and an alpha rejection factor of >98.2%. These data also include the first observation of a dependence of acoustic signal on alpha energy. Twelve single nuclear recoil event candidates were observed during the run. The candidate events exhibit timing characteristics that are not consistent with the hypothesis of a uniform time distribution, and no evidence for a dark matter signal is claimed. These data provide the most sensitive direct detection constraints on WIMP-proton spin-dependent scattering to date, with significant sensitivity at low WIMP masses for spin-independent WIMP-nucleon scattering. PMID:26196790

  1. En bloc resection of a C2–C3 upper cervical chordoma: Technical note

    PubMed Central

    Weil, Alexander G.; Shehadeh, Mohammed; Ayad, Tareck; Abboud, Olivier; Shedid, Daniel

    2015-01-01

    Background: Recently, en bloc spondylectomy for upper cervical chordomas has been reported. Most authors utilize the combined approaches (e.g., transoral tumor resection with anterior column reconstruction and primary pharyngeal closure without up-front flap repair). However, the 60% incidence of posterior pharyngeal wall dehiscence delays oral intake, typically requires an additional surgery (e.g. free-flap), and delays radiation therapy. Methods: Here, we demonstrate the efficacy of en bloc C2–C3 spondylectomy for the treatment of upper cervical chordomas utilizing a combined transoral followed by posterior approach. We used a novel anterior de-epithelialized submental island flap (SIF) as an underlay graft between the pharyngeal wall and cage/hardware to prevent pharyngeal wound dehiscence. Results: Despite a small pharyngeal fistula, the construct healed and the patient was disease-free 40 months later. Conclusion: En bloc C2–C3 spondylectomy for the treatment of an upper cervical chordoma typically requires a combined transoral and posterior approaches. This required utilization of an anterior SIF to promote adequate wound healing. This maneuver avoided incurring the typical complications of combined approaches (e.g. transoral tumor resection with anterior column reconstruction and primary pharyngeal closure without up-front flap repair). PMID:26693391

  2. Dark Matter Search Results from the PICO-2L C3F8 Bubble Chamber.

    PubMed

    Amole, C; Ardid, M; Asner, D M; Baxter, D; Behnke, E; Bhattacharjee, P; Borsodi, H; Bou-Cabo, M; Brice, S J; Broemmelsiek, D; Clark, K; Collar, J I; Cooper, P S; Crisler, M; Dahl, C E; Daley, S; Das, M; Debris, F; Dhungana, N; Farine, J; Felis, I; Filgas, R; Fines-Neuschild, M; Girard, F; Giroux, G; Hai, M; Hall, J; Harris, O; Jackson, C M; Jin, M; Krauss, C B; Lafrenière, M; Laurin, M; Lawson, I; Levine, I; Lippincott, W H; Mann, E; Martin, J P; Maurya, D; Mitra, P; Neilson, R; Noble, A J; Plante, A; Podviianiuk, R B; Priya, S; Robinson, A E; Ruschman, M; Scallon, O; Seth, S; Sonnenschein, A; Starinski, N; Štekl, I; Vázquez-Jáuregui, E; Wells, J; Wichoski, U; Zacek, V; Zhang, J

    2015-06-12

    New data are reported from the operation of a 2 liter C3F8 bubble chamber in the SNOLAB underground laboratory, with a total exposure of 211.5 kg days at four different energy thresholds below 10 keV. These data show that C3F8 provides excellent electron-recoil and alpha rejection capabilities at very low thresholds. The chamber exhibits an electron-recoil sensitivity of <3.5×10(-10) and an alpha rejection factor of >98.2%. These data also include the first observation of a dependence of acoustic signal on alpha energy. Twelve single nuclear recoil event candidates were observed during the run. The candidate events exhibit timing characteristics that are not consistent with the hypothesis of a uniform time distribution, and no evidence for a dark matter signal is claimed. These data provide the most sensitive direct detection constraints on WIMP-proton spin-dependent scattering to date, with significant sensitivity at low WIMP masses for spin-independent WIMP-nucleon scattering.

  3. Crystal structure of cytochrome c3 from Desulfovibrio desulfuricans Norway at 1.7 A resolution.

    PubMed

    Czjzek, M; Payan, F; Guerlesquin, F; Bruschi, M; Haser, R

    1994-11-01

    The crystal structure of cytochrome c3 (M(r) 13,000) from Desulfovibrio desulfuricans (118 residues, four heme groups) has been crystallographically refined to 1.7 A resolution using a simulated annealing method, based on the structure-model at 2.5 A resolution, already published. The final R-factor for 10,549 reflections was 0.198 covering the range from 5.5 to 1.7 A resolution. The individual temperature factors were refined for a total of 1059 protein atoms, together with 126 bound solvent molecules. The structure has been analyzed with respect to its detailed conformational properties, secondary structure features, temperature factor behaviour, bound solvent sites and heme geometry and ligation. The characteristic secondary structures of the polypeptide chain of this molecule are one extended alpha-helix, a short beta-strand and 13 reverse turns. The four heme groups are located in different structural environments, all highly exposed to solvent. The particular structural features of the heme environments are compared to the four hemes of the cytochrome c3 from Desulfovibrio vulgaris Miyazaki. PMID:7966289

  4. Spongy polyethersulfone membrane for hepatocyte cultivation: studies on human hepatoma C3A cells.

    PubMed

    Kinasiewicz, Andrzej; Smietanka, Anna; Dudziński, Konrad; Chwojnowski, Andrzej; Gajkowska, Barbara; Weryński, Andrzej

    2008-09-01

    There are different types of membranes used for hepatocyte cultivation. In our studies, spongy polyethersulfone (PES) membranes were examined as a support for hepatic cell cultivation in vitro. The extended surface of the membranes allows to introduce a high cell number especially in three-dimensional gel structure. Scanning electron microscopy analysis indicated that C3A cells used in our experiments grew well on PES membranes forming microvilli characteristic for normal hepatocytes. Analysis of cell viability proved that spongy PES membrane is well tolerated by J774 macrophages and did not stimulate nitric oxide synthesis. Bile canalicular structures were observed in fluorescence microscopy after F-actin staining with tetramethyl rhodamine iso-thiocyanate (TRITC)-phalloidin. The C3A cells showed high affinity to the PES membranes and adhered to almost 90% during the initial 24 h of incubation. Albumin production increased during static culture from the value of 805.2 +/- 284.4 (ng/24 h/initial 10(6) cells) during the first days, to 2017.6 +/- 505.9 (ng/24 h/initial 10(6) cells) after 10 days of culture. In conclusion, the spongy PES membranes can be used as scaffold for hepatocyte cultivation, especially for the creation of three-dimensional environments.

  5. The Copernicus Climate Change Service (C3S): A European Answer to Climate Change

    NASA Astrophysics Data System (ADS)

    Thepaut, Jean-Noel

    2016-04-01

    Copernicus is the European Commission's flagship Earth observation programme that delivers freely accessible operational data and information services. ECMWF has been entrusted to operate two key parts of the Copernicus programme, which will bring a consistent standard to the measurement, forecasting and prediction of atmospheric conditions and climate change: • The Copernicus Atmosphere Monitoring Service, CAMS, provides daily forecasts detailing the makeup composition of the atmosphere from the ground up to the stratosphere. • The Copernicus Climate Change Service (C3S) (in development) will routinely monitor and analyse more than 20 essential climate variables to build a global picture of our climate, from the past to the future, as well as developing customisable climate indicators for relevant economic sectors, such as energy, water management, agriculture, insurance, health…. C3S has now taken off and a number of proof-of-concept sectoral climate services have been initiated. This paper will focus on the description and expected outcome of these proof-of-concept activities as well as the definition of a roadmap towards a fully operational European Climate Change Service.

  6. Coherence Pathways with Cartesian Product Operators. The C3PO Method

    NASA Astrophysics Data System (ADS)

    Kingsley, P. B.

    The product-operator formalism using the Cartesian operator basis was modified, and the notation of Ix(φ) = Ixcos φ + Iysin φ and Iy(φ) = Iycos φ - Ixsin φ simplified the product-operator description of uncoupled or weakly coupled spins in multipulse sequences with arbitrary pulse phases and chemical-shift precessions. The compact Cartesian coordinate product- operator (C3PO) formalism is more compact than any other proposed basis set, easily provides complete coherence-pathway information, and provides better visualization than the original Cartesian basis set. Formulas for evolution under radiofrequency pulses, chemical-shift precession with spin-spin coupling, and multiple-quantum coherences are provided for weakly coupled IS and I 3S spin systems ( I = S = {1}/{2}) and for a strongly coupled IS (AB) spin system. Formulas are also provided for a spin coupled to an S = 1 spin. The C3PO formalism is compared with the spherical basis set, and examples are provided for STEAM-localized spectroscopy, COSY, and a strongly coupled AB spin system.

  7. Dark Matter Search Results from the PICO-2L C3F8 Bubble Chamber

    NASA Astrophysics Data System (ADS)

    Amole, C.; Ardid, M.; Asner, D. M.; Baxter, D.; Behnke, E.; Bhattacharjee, P.; Borsodi, H.; Bou-Cabo, M.; Brice, S. J.; Broemmelsiek, D.; Clark, K.; Collar, J. I.; Cooper, P. S.; Crisler, M.; Dahl, C. E.; Daley, S.; Das, M.; Debris, F.; Dhungana, N.; Farine, J.; Felis, I.; Filgas, R.; Fines-Neuschild, M.; Girard, F.; Giroux, G.; Hai, M.; Hall, J.; Harris, O.; Jackson, C. M.; Jin, M.; Krauss, C. B.; Lafrenière, M.; Laurin, M.; Lawson, I.; Levine, I.; Lippincott, W. H.; Mann, E.; Martin, J. P.; Maurya, D.; Mitra, P.; Neilson, R.; Noble, A. J.; Plante, A.; Podviianiuk, R. B.; Priya, S.; Robinson, A. E.; Ruschman, M.; Scallon, O.; Seth, S.; Sonnenschein, A.; Starinski, N.; Štekl, I.; Vázquez-Jáuregui, E.; Wells, J.; Wichoski, U.; Zacek, V.; Zhang, J.; PICO Collaboration

    2015-06-01

    New data are reported from the operation of a 2 liter C3F8 bubble chamber in the SNOLAB underground laboratory, with a total exposure of 211.5 kg days at four different energy thresholds below 10 keV. These data show that C3F8 provides excellent electron-recoil and alpha rejection capabilities at very low thresholds. The chamber exhibits an electron-recoil sensitivity of <3.5 ×1 0-10 and an alpha rejection factor of >98.2 %. These data also include the first observation of a dependence of acoustic signal on alpha energy. Twelve single nuclear recoil event candidates were observed during the run. The candidate events exhibit timing characteristics that are not consistent with the hypothesis of a uniform time distribution, and no evidence for a dark matter signal is claimed. These data provide the most sensitive direct detection constraints on WIMP-proton spin-dependent scattering to date, with significant sensitivity at low WIMP masses for spin-independent WIMP-nucleon scattering.

  8. Engineering C4 photosynthesis into C3 chassis in the synthetic biology age.

    PubMed

    Schuler, Mara L; Mantegazza, Otho; Weber, Andreas P M

    2016-07-01

    C4 photosynthetic plants outperform C3 plants in hot and arid climates. By concentrating carbon dioxide around Rubisco C4 plants drastically reduce photorespiration. The frequency with which plants evolved C4 photosynthesis independently challenges researchers to unravel the genetic mechanisms underlying this convergent evolutionary switch. The conversion of C3 crops, such as rice, towards C4 photosynthesis is a long-standing goal. Nevertheless, at the present time, in the age of synthetic biology, this still remains a monumental task, partially because the C4 carbon-concentrating biochemical cycle spans two cell types and thus requires specialized anatomy. Here we review the advances in understanding the molecular basis and the evolution of the C4 trait, advances in the last decades that were driven by systems biology methods. In this review we emphasise essential genetic engineering tools needed to translate our theoretical knowledge into engineering approaches. With our current molecular understanding of the biochemical C4 pathway, we propose a simplified rational engineering model exclusively built with known C4 metabolic components. Moreover, we discuss an alternative approach to the progressing international engineering attempts that would combine targeted mutagenesis and directed evolution. PMID:26945781

  9. Transgenic approaches to manipulate the environmental responses of the C3 carbon fixation cycle.

    PubMed

    Raines, Christine A

    2006-03-01

    The limitation to photosynthetic CO2 assimilation in C3 plants in hot, dry environments is dominated by ribulose 1.5-bisphosphate carboxylase/oxygenase (Rubisco) because CO2 availability is restricted and photorespiration is stimulated. Using a combination of genetic engineering and transgenic technology, three approaches to reduce photorespiration have been taken; two of these focused on increasing the carboxylation efficiency of Rubisco either by reducing the oxygenase reaction directly or by manipulating the Rubisco enzyme by concentrating CO2 in the region of Rubisco through the introduction of enzymes of the C4 pathway. The third approach attempted to reduce photorespiration directly by manipulation of enzymes in this pathway. The progress in each of these areas is discussed, and the most promising approaches are highlighted. Under saturating CO2 conditions, Rubisco did not limit photosynthesis, and limitation shifted to ribulose bisphosphate (RuBP) regeneration capacity of the C3 cycle. Transgenic analysis was used to identify the specific enzymes that may be targets for improving carbon fixation, and the way this may be exploited in the high CO2 future is considered.

  10. Dark matter search results from the PICO-2L C$_3$F$_8$ bubble chamber

    DOE PAGES

    Amole, C.

    2015-06-11

    New data are reported from the operation of a 2 liter C3F8 bubble chamber in the SNOLAB underground laboratory, with a total exposure of 211.5 kg days at four different energy thresholds below 10 keV. These data show that C3F8 provides excellent electron-recoil and alpha rejection capabilities at very low thresholds. The chamber exhibits an electron-recoil sensitivity of < 3.5 × 10–10 and an alpha rejection factor of > 98.2%. These data also include the first observation of a dependence of acoustic signal on alpha energy. Twelve single nuclear recoil event candidates were observed during the run. The candidate eventsmore » exhibit timing characteristics that are not consistent with the hypothesis of a uniform time distribution, and no evidence for a dark matter signal is claimed. Lastly, these data provide the most sensitive direct detection constraints on WIMP-proton spin-dependent scattering to date, with significant sensitivity at low WIMP masses for spin-independent WIMP-nucleon scattering.« less

  11. Engineering C4 photosynthesis into C3 chassis in the synthetic biology age.

    PubMed

    Schuler, Mara L; Mantegazza, Otho; Weber, Andreas P M

    2016-07-01

    C4 photosynthetic plants outperform C3 plants in hot and arid climates. By concentrating carbon dioxide around Rubisco C4 plants drastically reduce photorespiration. The frequency with which plants evolved C4 photosynthesis independently challenges researchers to unravel the genetic mechanisms underlying this convergent evolutionary switch. The conversion of C3 crops, such as rice, towards C4 photosynthesis is a long-standing goal. Nevertheless, at the present time, in the age of synthetic biology, this still remains a monumental task, partially because the C4 carbon-concentrating biochemical cycle spans two cell types and thus requires specialized anatomy. Here we review the advances in understanding the molecular basis and the evolution of the C4 trait, advances in the last decades that were driven by systems biology methods. In this review we emphasise essential genetic engineering tools needed to translate our theoretical knowledge into engineering approaches. With our current molecular understanding of the biochemical C4 pathway, we propose a simplified rational engineering model exclusively built with known C4 metabolic components. Moreover, we discuss an alternative approach to the progressing international engineering attempts that would combine targeted mutagenesis and directed evolution.

  12. An ab initio study of the C3(+) cation using multireference methods

    NASA Technical Reports Server (NTRS)

    Taylor, Peter R.; Martin, J. M. L.; Francois, J. P.; Gijbels, R.

    1991-01-01

    The energy difference between the linear 2 sigma(sup +, sub u) and cyclic 2B(sub 2) structures of C3(+) has been investigated using large (5s3p2d1f) basis sets and multireference electron correlation treatments, including complete active space self consistent fields (CASSCF), multireference configuration interaction (MRCI), and averaged coupled-pair functional (ACPF) methods, as well as the single-reference quadratic configuration interaction (QCISD(T)) method. Our best estimate, including a correction for basis set incompleteness, is that the linear form lies above the cyclic from by 5.2(+1.5 to -1.0) kcal/mol. The 2 sigma(sup +, sub u) state is probably not a transition state, but a local minimum. Reliable computation of the cyclic/linear energy difference in C3(+) is extremely demanding of the electron correlation treatment used: of the single-reference methods previously considered, CCSD(T) and QCISD(T) perform best. The MRCI + Q(0.01)/(4s2p1d) energy separation of 1.68 kcal/mol should provide a comparison standard for other electron correlation methods applied to this system.

  13. Complement anaphylatoxin C3a is a potent inducer of embryonic chick retina regeneration

    PubMed Central

    Haynes, Tracy; Luz-Madrigal, Agustin; Reis, Edimara S.; Echeverri Ruiz, Nancy P.; Grajales-Esquivel, Erika; Tzekou, Apostolia; Tsonis, Panagiotis A.; Lambris, John D.; Del Rio-Tsonis, Katia

    2013-01-01

    Identifying the initiation signals for tissue regeneration in vertebrates is one of the major challenges in regenerative biology. Much of the research thus far has indicated that certain growth factors have key roles. Here we show that complement fragment C3a is sufficient to induce complete regeneration of the embryonic chick retina from stem/progenitor cells present in the eye, independent of fibroblast growth factor receptor signaling. Instead, C3a induces retina regeneration via STAT3 activation, which in turn activates the injury- and inflammation-responsive factors, IL-6, IL-8 and TNF-α. This activation sets forth regulation of Wnt2b, Six3 and Sox2, genes associated with retina stem and progenitor cells. Thus, our results establish a mechanism for retina regeneration based on injury and inflammation signals. Furthermore, our results indicate a unique function for complement anaphylatoxins that implicate these molecules in the induction and complete regeneration of the retina, opening new avenues of experimentation in the field. PMID:23942241

  14. Starch Accumulation in the Bundle Sheaths of C3 Plants: A Possible Pre-Condition for C4 Photosynthesis.

    PubMed

    Miyake, Hiroshi

    2016-05-01

    C4 plants have evolved >60 times from their C3 ancestors. C4 photosynthesis requires a set of closely co-ordinated anatomical and biochemical characteristics. However, it is now recognized that the evolution of C4 plants requires fewer changes than had ever been considered, because of the genetic, biochemical and anatomical pre-conditions of C3 ancestors that were recruited into C4 photosynthesis. Therefore, the pre-conditions in C3 plants are now being actively investigated to clarify the evolutionary trajectory from C3 to C4 plants and to engineer C4 traits efficiently into C3 crops. In the present mini review, the anatomical characteristics of C3 and C4 plants are briefly reviewed and the importance of the bundle sheath for the evolution of C4 photosynthesis is described. For example, while the bundle sheath of C3 rice plants accumulates large amounts of starch in the developing leaf blade and at the lamina joint of the mature leaf, the starch sheath function is also observed during leaf development in starch accumulator grasses regardless of photosynthetic type. The starch sheath function of C3 plants is therefore also implicated as a possible pre-condition for the evolution of C4 photosynthesis. The phylogenetic relationships between the types of storage carbohydrates and of photosynthesis need to be clarified in the future. PMID:26936788

  15. Enhanced visible-light photocatalytic activity of g-C3N4/TiO2 films.

    PubMed

    Boonprakob, Natkritta; Wetchakun, Natda; Phanichphant, Sukon; Waxler, David; Sherrell, Peter; Nattestad, Andrew; Chen, Jun; Inceesungvorn, Burapat

    2014-03-01

    Enhanced photocatalytic degradation of methylene blue (MB) using graphitic carbon nitride/titanium dioxide (g-C3N4/TiO2) catalyst films has been demonstrated in this present work. The g-C3N4/TiO2 composites were prepared by directly heating the mixture of melamine and pre-synthesized TiO2 nanoparticles in Ar gas flow. The g-C3N4 contents in the g-C3N4/TiO2 composites were varied as 0, 20, 50 and 70 wt%. It was found that the visible-light-induced photocatalytic degradation of MB was remarkably increased upon coupling TiO2 with g-C3N4 and the best degradation performance of ~70% was obtained from 50 wt% g-C3N4 loading content. Results from UV-vis absorption study, Electron microscopy, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy suggest that the improved photoactivity is due to a decrease in band gap energy, an increased light absorption in visible light region and possibly an enhanced electron-hole separation efficiency as a result of effective interfacial electron transfer between TiO2 and g-C3N4 of the g-C3N4/TiO2 composite film. Based on the obtained results, the possible MB degradation mechanism is ascribed mainly to the generation of active species induced by the photogenerated electrons. PMID:24407703

  16. The mammalian class 3 PI3K (PIK3C3) is required for early embryogenesis and cell proliferation.

    PubMed

    Zhou, Xiang; Takatoh, Jun; Wang, Fan

    2011-01-01

    The Pik3c3 gene encodes an 887 amino acid lipid kinase, phosphoinositide-3-kinase class 3 (PIK3C3). PIK3C3 is known to regulate various intracellular membrane trafficking events. However, little is known about its functions during early embryogenesis in mammals. To investigate the function of PIK3C3 in vivo, we generated Pik3c3 null mice. We show here that Pik3c3 heterozygous are normal and fertile. In contrast, Pik3c3 homozygous mutants are embryonic lethal and die between E7.5 and E8.5 of embryogenesis. Mutant embryos are poorly developed with no evidence of mesoderm formation, and suffer from severely reduced cell proliferations. Cell proliferation defect is also evident in vitro, where mutant blastocysts in culture fail to give rise to typical colonies formed by inner cell mass. Electron microscopic analysis revealed that epiblast cells in mutant embryos appear normal, whereas the visceral endoderm cells contain larger vesicles inside the lipid droplets. Finally, we provide evidence that mTOR signaling is drastically reduced in Pik3c3 null embryos, which could be a major contributor to the observed proliferation and embryogenesis defects. PMID:21283715

  17. Molecular cloning and expression analysis of Pleurodeles waltl complement component C3 under normal physiological conditions and environmental stresses.

    PubMed

    Guéguinou, Nathan; Huin-Schohn, Cécile; Ouzren-Zarhloul, Nassima; Ghislin, Stéphanie; Frippiat, Jean-Pol

    2014-10-01

    C3 is a component of the complement system that plays a central role in immunity, development and tissue regeneration. In this study, we isolated the C3 cDNA of the Iberian ribbed newt Pleurodeles waltl. This cDNA encodes a 1637 amino acid protein with an estimated molecular mass of 212.5 kDa. The deduced amino acid sequence showed that P. waltl C3 contains all the conserved domains known to be critical for C3 function. Quantitative real-time PCR (qRT-PCR) demonstrated that under normal physiological conditions, P. waltl C3 mRNA is expressed early during development because it is likely required for neurulation. Then, its expression increased as the immune system developed. In adults, the liver is the richest source of C3, though other tissues can also contribute. Further analysis of C3 expression demonstrated that C3 transcription increased when P. waltl larvae were exposed to pH or temperature stress, suggesting that environmental modifications might affect this animal's defenses against pathogens.

  18. Magnetic Fe@g-C3N4: A Photoactive Catalyst for the Hydrogenation of Alkenes and Alkynes

    EPA Science Inventory

    A photoactive catalyst, Fe@g-C3N4, has been developed for the hydrogenation of alkenes and alkynes using hydrazine hydrate as a source of hydrogen. The magnetically separable Fe@g-C3N4 eliminates the use of high pressure hydrogenation and the reaction can be accomplished using vi...

  19. Mesophyll cells of C4 plants have fewer chloroplasts than those of closely related C3 plants.

    PubMed

    Stata, Matt; Sage, Tammy L; Rennie, Troy D; Khoshravesh, Roxana; Sultmanis, Stefanie; Khaikin, Yannay; Ludwig, Martha; Sage, Rowan F

    2014-11-01

    The evolution of C(4) photosynthesis from C(3) ancestors eliminates ribulose bisphosphate carboxylation in the mesophyll (M) cell chloroplast while activating phosphoenolpyruvate (PEP) carboxylation in the cytosol. These changes may lead to fewer chloroplasts and different chloroplast positioning within M cells. To evaluate these possibilities, we compared chloroplast number, size and position in M cells of closely related C(3), C(3) -C(4) intermediate and C(4) species from 12 lineages of C(4) evolution. All C(3) species had more chloroplasts per M cell area than their C(4) relatives in high-light growth conditions. C(3) species also had higher chloroplast coverage of the M cell periphery than C(4) species, particularly opposite intercellular air spaces. In M cells from 10 of the 12 C(4) lineages, a greater fraction of the chloroplast envelope was pulled away from the plasmalemma in the C(4) species than their C(3) relatives. C(3) -C(4) intermediate species generally exhibited similar patterns as their C(3) relatives. We interpret these results to reflect adaptive shifts that facilitate efficient C(4) function by enhancing diffusive access to the site of primary carbon fixation in the cytosol. Fewer chloroplasts in C(4) M cells would also reduce shading of the bundle sheath chloroplasts, which also generate energy required by C(4) photosynthesis.

  20. 26 CFR 31.6302(c)-3 - Deposit rules for taxes under the Federal Unemployment Tax Act.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Unemployment Tax Act. 31.6302(c)-3 Section 31.6302(c)-3 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... for taxes under the Federal Unemployment Tax Act. (a) Requirement—(1) In general. Except as provided... deposit. For the requirement to deposit tax under the Federal Unemployment Tax Act by electronic...

  1. 26 CFR 31.6302(c)-3 - Deposit rules for taxes under the Federal Unemployment Tax Act.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Unemployment Tax Act. 31.6302(c)-3 Section 31.6302(c)-3 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... for taxes under the Federal Unemployment Tax Act. (a) Requirement—(1) In general. Except as provided... deposit. For the requirement to deposit tax under the Federal Unemployment Tax Act by electronic...

  2. 26 CFR 31.6302(c)-3 - Deposit rules for taxes under the Federal Unemployment Tax Act.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Unemployment Tax Act. 31.6302(c)-3 Section 31.6302(c)-3 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... for taxes under the Federal Unemployment Tax Act. (a) Requirement—(1) In general. Except as provided... deposit. For the requirement to deposit tax under the Federal Unemployment Tax Act by electronic...

  3. 26 CFR 31.6302(c)-3 - Deposit rules for taxes under the Federal Unemployment Tax Act.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Unemployment Tax Act. 31.6302(c)-3 Section 31.6302(c)-3 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... for taxes under the Federal Unemployment Tax Act. (a) Requirement—(1) In general. Except as provided... deposit. For the requirement to deposit tax under the Federal Unemployment Tax Act by electronic...

  4. Q and A about the College, Career, and Civic Life (C3) Framework for Social Studies State Standards

    ERIC Educational Resources Information Center

    Herczog, Michelle

    2013-01-01

    The "College, Career, and Civic Life (C3) Framework for Social Studies State Standards: State Guidance for Enhancing the Rigor of K-12 Civics, Economics, Geography, and History" will soon be released. The C3 Framework was developed to serve two audiences: for states to upgrade their state social studies standards, and for…

  5. In vitro CAPE inhibitory activity towards human AKR1C3 and the molecular basis.

    PubMed

    Li, Cuiyun; Zhao, Yining; Zheng, Xuehua; Zhang, Hong; Zhang, Liping; Chen, Yunyun; Li, Qing; Hu, Xiaopeng

    2016-06-25

    AKR1C3 is a critical enzyme for producing testosterone and 5α-DHT in the human body. Inhibiting AKR1C3 is a potential target for treating castration-resistant prostate cancer (CRPC). To find AKR1C3 inhibitors with a new molecular skeleton and binding mode, we analyzed the in vitro inhibitory activity of caffeic acid phenethyl ester (CAPE) and eight other phenolic acid analogues towards AKR1C3 and six other human AKR1 enzymes. We analyzed CAPE and octyl gallate interactions with AKR1C3 using X-ray crystallography, which provided a molecular basis for understanding the phenolic acid inhibitory activity and selectivity towards human AKR1s. PMID:27163852

  6. Corrosion performance of bi-layer Ni/Cr2C3-NiCr HVAF thermal spray coating

    NASA Astrophysics Data System (ADS)

    Sadeghimeresht, E.; Markocsan, N.; Nylén, P.; Björklund, S.

    2016-04-01

    The corrosion behavior of three HVAF thermal spray coating systems (A: single-layer Ni, B: single-layer Cr2C3-NiCr coatings, and C: bi-layer Ni/Cr2C3-NiCr coating) was comparatively studied using immersion, salt spray, and electrochemical tests. Polarization and EIS results showed that the corrosion behavior of Cr2C3-NiCr coatings in 3.5 wt.% NaCl solution was significantly improved by adding the intermediate layer of Ni. It was illustrated that the polarization resistance of the bi-layer Ni/Cr2C3-NiCr and single-layer Cr2C3-NiCr coatings were around 194 and 38 kΩ cm2, respectively. Microstructure analysis revealed that the bond coating successfully prevented the corrosion propagation toward the coating.

  7. Sonochemical Synthesis of CdS/C3N4 Composites with Efficient Photocatalytic Performance Under Visible Light Irradiation.

    PubMed

    Chai, Bo; Wang, Xing

    2016-02-01

    The CdS/C3N4 composites with efficient photocatalytic performance under visible light irradiation were synthesized by a facile sonochemical route. The as-prepared CdS/C3N4 composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution trans- mission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance absorption spectra (DRS), fourier transform infrared spectroscopy (FTIR) and photoluminescence spectra (PL). The photocatalytic degradation of rhodamine B (RhB) by the CdS/C3N4 composites was explored and optimized, suggesting the optimal amount of CdS in the composites was 50 wt%. The significantly enhanced photocatalytic activity of CdS/C3N4 composites could be attributed to the effectively interfacial transfer of photogenerated charge carriers between CdS and C3N4, which restrained the recombination of electron-hole pairs. PMID:27433724

  8. Sonochemical Synthesis of CdS/C3N4 Composites with Efficient Photocatalytic Performance Under Visible Light Irradiation.

    PubMed

    Chai, Bo; Wang, Xing

    2016-02-01

    The CdS/C3N4 composites with efficient photocatalytic performance under visible light irradiation were synthesized by a facile sonochemical route. The as-prepared CdS/C3N4 composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution trans- mission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance absorption spectra (DRS), fourier transform infrared spectroscopy (FTIR) and photoluminescence spectra (PL). The photocatalytic degradation of rhodamine B (RhB) by the CdS/C3N4 composites was explored and optimized, suggesting the optimal amount of CdS in the composites was 50 wt%. The significantly enhanced photocatalytic activity of CdS/C3N4 composites could be attributed to the effectively interfacial transfer of photogenerated charge carriers between CdS and C3N4, which restrained the recombination of electron-hole pairs.

  9. Comparative Hydrodynamics of Bacterial Polymorphism

    NASA Astrophysics Data System (ADS)

    Spagnolie, Saverio E.; Lauga, Eric

    2011-02-01

    Most bacteria swim through fluids by rotating helical flagella which can take one of 12 distinct polymorphic shapes, the most common of which is the normal form used during forward swimming runs. To shed light on the prevalence of the normal form in locomotion, we gather all available experimental measurements of the various polymorphic forms and compute their intrinsic hydrodynamic efficiencies. The normal helical form is found to be the most efficient of the 12 polymorphic forms by a significant margin—a conclusion valid for both the peritrichous and polar flagellar families, and robust to a change in the effective flagellum diameter or length. Hence, although energetic costs of locomotion are small for bacteria, fluid mechanical forces may have played a significant role in the evolution of the flagellum.

  10. Complement Component C3 Binds to Activated Normal Platelets without Preceding Proteolytic Activation and Promotes Binding to Complement Receptor 1

    PubMed Central

    Hamad, Osama A.; Nilsson, Per H.; Wouters, Diana; Lambris, John D.; Ekdahl, Kristina N.; Nilsson, Bo

    2010-01-01

    It has been reported that complement is activated on the surface of activated platelets, despite the presence of multiple regulators of complement activation. To reinvestigate the mechanisms by which activated platelets bind to complement components, the presence of complement proteins on the surfaces of nonactivated and thrombin receptor-activating peptide-activated platelets was analyzed by flow cytometry and Western blot analyses. C1q, C4, C3, and C9 were found to bind to thrombin receptor-activating peptide-activated platelets in lepirudin-anticoagulated platelet-rich plasma (PRP) and whole blood. However, inhibiting complement activation at the C1q or C3 level did not block the binding of C3 to activated platelets. Diluting PRP and chelating divalent cations also had no effect, further indicating that the deposition of complement components was independent of complement activation. Furthermore, washed, activated platelets bound added C1q and C3 to the same extent as platelets in PRP. The use of mAbs against different forms of C3 demonstrated that the bound C3 consisted of C3(H2O). Furthermore, exogenously added soluble complement receptor 1 was shown to bind to this form of platelet-bound C3. These observations indicate that there is no complement activation on the surface of platelets under physiological conditions. This situation is in direct contrast to a number of pathological conditions in which regulators of complement activation are lacking and thrombocytopenia and thrombotic disease are the ultimate result. However, the generation of C3(H2O) represents nonproteolytic activation of C3 and after factor I cleavage may act as a ligand for receptor binding. PMID:20139276

  11. Deciphering the Regulon of Streptomyces coelicolor AbrC3, a Positive Response Regulator of Antibiotic Production

    PubMed Central

    Rico, Sergio; Santamaría, Ramón I.; Yepes, Ana; Rodríguez, Héctor; Laing, Emma; Bucca, Giselda; Smith, Colin P.

    2014-01-01

    The atypical two-component system (TCS) AbrC1/C2/C3 (encoded by SCO4598, SCO4597, and SCO4596), comprising two histidine kinases (HKs) and a response regulator (RR), is crucial for antibiotic production in Streptomyces coelicolor and for morphological differentiation under certain nutritional conditions. In this study, we demonstrate that deletion of the RR-encoding gene, abrC3 (SCO4596), results in a dramatic decrease in actinorhodin (ACT) and undecylprodiginine (RED) production and delays morphological development. In contrast, the overexpression of abrC3 in the parent strain leads to a 33% increase in ACT production in liquid medium. Transcriptomic analysis and chromatin immunoprecipitation with microarray technology (ChIP-chip) analysis of the ΔabrC3 mutant and the parent strain revealed that AbrC3 directly controls ACT production by binding to the actII-ORF4 promoter region; this was independently verified by in vitro DNA-binding assays. This binding is dependent on the sequence 5′-GAASGSGRMS-3′. In contrast, the regulation of RED production is not due to direct binding of AbrC3 to either the redZ or redD promoter region. This study also revealed other members of the AbrC3 regulon: AbrC3 is a positive autoregulator which also binds to the promoter regions of SCO0736, bdtA (SCO3328), absR1 (SCO6992), and SCO6809. The direct targets share the 10-base consensus binding sequence and may be responsible for some of the phenotypes of the ΔabrC3 mutant. The identification of the AbrC3 regulon as part of the complex regulatory network governing antibiotic production widens our knowledge regarding TCS involvement in control of antibiotic synthesis and may contribute to the rational design of new hyperproducer host strains through genetic manipulation of such systems. PMID:24509929

  12. Evolution of the Phosphoenolpyruvate Carboxylase Protein Kinase Family in C3 and C4 Flaveria spp.1[W][OPEN

    PubMed Central

    Aldous, Sophia H.; Weise, Sean E.; Sharkey, Thomas D.; Waldera-Lupa, Daniel M.; Stühler, Kai; Mallmann, Julia; Groth, Georg; Gowik, Udo; Westhoff, Peter; Arsova, Borjana

    2014-01-01

    The key enzyme for C4 photosynthesis, Phosphoenolpyruvate Carboxylase (PEPC), evolved from nonphotosynthetic PEPC found in C3 ancestors. In all plants, PEPC is phosphorylated by Phosphoenolpyruvate Carboxylase Protein Kinase (PPCK). However, differences in the phosphorylation pattern exist among plants with these photosynthetic types, and it is still not clear if they are due to interspecies differences or depend on photosynthetic type. The genus Flaveria contains closely related C3, C3-C4 intermediate, and C4 species, which are evolutionarily young and thus well suited for comparative analysis. To characterize the evolutionary differences in PPCK between plants with C3 and C4 photosynthesis, transcriptome libraries from nine Flaveria spp. were used, and a two-member PPCK family (PPCKA and PPCKB) was identified. Sequence analysis identified a number of C3- and C4-specific residues with various occurrences in the intermediates. Quantitative analysis of transcriptome data revealed that PPCKA and PPCKB exhibit inverse diel expression patterns and that C3 and C4 Flaveria spp. differ in the expression levels of these genes. PPCKA has maximal expression levels during the day, whereas PPCKB has maximal expression during the night. Phosphorylation patterns of PEPC varied among C3 and C4 Flaveria spp. too, with PEPC from the C4 species being predominantly phosphorylated throughout the day, while in the C3 species the phosphorylation level was maintained during the entire 24 h. Since C4 Flaveria spp. evolved from C3 ancestors, this work links the evolutionary changes in sequence, PPCK expression, and phosphorylation pattern to an evolutionary phase shift of kinase activity from a C3 to a C4 mode. PMID:24850859

  13. Depletion of C3orf1/TIMMDC1 inhibits migration and proliferation in 95D lung carcinoma cells.

    PubMed

    Wu, Huiling; Wang, Wenbing; Xu, Huaxi

    2014-01-01

    In our previous study, we identified an association of high expression of c3orf1, also known as TIMMDC1 (translocase of inner mitochondrial membrane domain-containing protein 1), with metastatic characteristics in lung carcinoma cells. To investigate the preliminary function and mechanism of this mitochondrial protein, we depleted C3orf1 expression by introducing siRNA into 95D lung carcinoma cells. We demonstrated that C3orf1 depletion significantly suppressed 95D cell growth and migration. We confirmed C3orf1 localization in the inner mitochondrial membrane and showed that mitochondrial viability, membrane potential, and ATPase activity were remarkably reduced upon depletion of C3orf1. Microarray data indicated that genes involved in regulation of cell death, migration, and cell-cycle arrest were significantly altered after C3orf1 depletion for 48 h. The expression of genes involved in focal adhesion, ECM-receptor interaction, and p53-signaling pathways were notably altered. Furthermore, cell-cycle arrest genes such as CCNG2 and PTEN as well as genes involved in cell migration inhibition, such as TIMP3 and COL3A1, were upregulated after C3orf1 depletion in 95D cells. Concurrently, expression of the migration-promoting gene NUPR1 was markedly reduced, as confirmed by real-time PCR. We conclude that C3orf1 is critical for mitochondrial function, migration, and proliferation in 95D lung carcinoma cells. Depletion of C3orf1 inhibited cell migration and cell proliferation in association with upregulation of genes involved in cell-cycle arrest and cell migration inhibition. These results suggest that C3orf1 (TIMMDC1) may be a viable treatment target for lung carcinoma, and that further study of the role of this protein in lung carcinoma pathogenesis is justified. PMID:25391042

  14. The Copernicus Climate Change Service (C3S): Open Access to a Climate Data Store

    NASA Astrophysics Data System (ADS)

    Thepaut, Jean-Noel; Dee, Dick

    2016-04-01

    In November 2014, The European Centre for Medium-range Weather Forecasts (ECMWF) signed an agreement with the European Commission to deliver two of the Copernicus Earth Observation Programme Services on the Commission's behalf. The ECMWF delivered services - the Copernicus Climate Change Service (C3S) and Atmosphere Monitoring Service (CAMS) - will bring a consistent standard to how we monitor and predict atmospheric conditions and climate change. They will maximise the potential of past, current and future earth observations - ground, ocean, airborne, satellite - and analyse these to monitor and predict atmospheric conditions and in the future, climate change. With the wealth of free and open data that the services provide, they will help business users to assess the impact of their business decisions and make informed choices, delivering a more energy efficient and climate aware economy. These sound investment decisions now will not only stimulate growth in the short term, but reduce the impact of climate change on the economy and society in the future. C3S is in its proof of concept phase and through its Climate Data Store will provide • global and regional climate data reanalyses; • multi-model seasonal forecasts; • customisable visual data to enable examination of wide range of scenarios and model the impact of changes; • access to all the underlying data, including climate data records from various satellite and in-situ observations. In addition, C3S will provide key indicators on climate change drivers (such as carbon dioxide) and impacts (such as reducing glaciers). The aim of these indicators will be to support European adaptation and mitigation policies in a number of economic sectors. At the heart of the Service is the provision of open access to a one stop shop (the Climate Data Store) of climate data and modelling, analysing more than 20 Essential Climate Variables to build a global picture of our past, present and future climate and developing

  15. Design and development of TT30, a novel C3d-targeted C3/C5 convertase inhibitor for treatment of human complement alternative pathway-mediated diseases.

    PubMed

    Fridkis-Hareli, Masha; Storek, Michael; Mazsaroff, Istvan; Risitano, Antonio M; Lundberg, Ante S; Horvath, Christopher J; Holers, V Michael

    2011-10-27

    To selectively modulate human complement alternative pathway (CAP) activity implicated in a wide range of acute and chronic inflammatory conditions and to provide local cell surface and tissue-based inhibition of complement-induced damage, we developed TT30, a novel therapeutic fusion protein linking the human complement receptor type 2 (CR2/CD21) C3 fragment (C3frag = iC3b, C3dg, C3d)-binding domain with the CAP inhibitory domain of human factor H (fH). TT30 efficiently blocks ex vivo CAP-dependent C3frag accumulation on activated surfaces, membrane attack complex (MAC) formation and hemolysis of RBCs in a CR2-dependent manner, and with a ∼ 150-fold potency gain over fH, without interference of C3 activation or MAC formation through the classic and lectin pathways. TT30 protects RBCs from hemolysis and remains bound and detectable for at least 24 hours. TT30 selectively inhibits CAP in cynomolgus monkeys and is bioavailable after subcutaneous injection. Using a unique combination of targeting and effector domains, TT30 controls cell surface CAP activation and has substantial potential utility for the treatment of human CAP-mediated diseases.

  16. Design and development of TT30, a novel C3d-targeted C3/C5 convertase inhibitor for treatment of human complement alternative pathway-mediated diseases.

    PubMed

    Fridkis-Hareli, Masha; Storek, Michael; Mazsaroff, Istvan; Risitano, Antonio M; Lundberg, Ante S; Horvath, Christopher J; Holers, V Michael

    2011-10-27

    To selectively modulate human complement alternative pathway (CAP) activity implicated in a wide range of acute and chronic inflammatory conditions and to provide local cell surface and tissue-based inhibition of complement-induced damage, we developed TT30, a novel therapeutic fusion protein linking the human complement receptor type 2 (CR2/CD21) C3 fragment (C3frag = iC3b, C3dg, C3d)-binding domain with the CAP inhibitory domain of human factor H (fH). TT30 efficiently blocks ex vivo CAP-dependent C3frag accumulation on activated surfaces, membrane attack complex (MAC) formation and hemolysis of RBCs in a CR2-dependent manner, and with a ∼ 150-fold potency gain over fH, without interference of C3 activation or MAC formation through the classic and lectin pathways. TT30 protects RBCs from hemolysis and remains bound and detectable for at least 24 hours. TT30 selectively inhibits CAP in cynomolgus monkeys and is bioavailable after subcutaneous injection. Using a unique combination of targeting and effector domains, TT30 controls cell surface CAP activation and has substantial potential utility for the treatment of human CAP-mediated diseases. PMID:21860027

  17. Genetics Home Reference: catecholaminergic polymorphic ventricular tachycardia

    MedlinePlus

    ... for This Page Cerrone M, Napolitano C, Priori SG. Catecholaminergic polymorphic ventricular tachycardia: A paradigm to understand ... on PubMed Central Liu N, Ruan Y, Priori SG. Catecholaminergic polymorphic ventricular tachycardia. Prog Cardiovasc Dis. 2008 ...

  18. Variation in AKR1C3, which Encodes the Neuroactive Steroid Synthetic Enzyme 3α-HSD Type 2 (17β-HSD Type 5), Moderates the Subjective Effects of Alcohol

    PubMed Central

    Milivojevic, Verica; Feinn, Richard; Kranzler, Henry R.; Covault, Jonathan

    2014-01-01

    Rationale Animal models suggest that neuroactive steroids contribute to alcohol’s acute effects. We previously reported that a common non-synonymous polymorphism, AKR1C3*2 in the gene encoding the enzyme 3α-HSD2/17β-HSD5 and a synonymous SNP, rs248793, in SRD5A1, which encodes 5α-reductase, were associated with alcohol dependence (AD). Objectives To investigate whether these polymorphisms moderate subjective effects of alcohol in humans and whether AKR1C3*2 affects neuroactive steroid synthesis. Methods 65 Caucasian men (34 lighter and 31 heavier drinkers; mean age 26.2 y) participated in a double-blind laboratory study where they consumed drinks containing no ethanol or 0.8 g/kg of ethanol. Breath alcohol, heart rate (HR), and self-reported alcohol effects were measured at 40-min intervals and genotype was examined as a moderator of alcohol’s effects. Levels of the neuroactive steroid 5α-androstane-3α,17β-diol and its precursors, 3α,5α-androsterone and dihydrotestosterone, were measured at study entry using GC/MS. Results Initially, carriers of the AD-protective AK1C3*2 G-allele had higher levels of 5α-androstane-3α,17β-diol relative to the precursor 3α,5α-androsterone than C-allele homozygotes. AKR1C3*2 G-allele carriers exhibited greater increases in heart rate and stimulant and sedative effects of alcohol than C-allele homozygotes. The genotype effects on sedation were observed only in heavier drinkers. The only effect of the SRD5A1 SNP was to moderate HR. There were no interactive effects of the two SNPs. Conclusions The observed effects of variation in a gene encoding a neuroactive steroid biosynthetic enzyme on the rate of 17p–reduction of androsterone relative to androstanediol and on alcohol’s sedative effects may help to explain the association of AKR1C3*2 with AD. PMID:24838369

  19. Differential Mycobacterium bovis BCG Vaccine-Derived Efficacy in C3Heb/FeJ and C3H/HeOuJ Mice Exposed to a Clinical Strain of Mycobacterium tuberculosis

    PubMed Central

    Henao-Tamayo, Marcela; Obregón-Henao, Andrés; Creissen, Elizabeth; Shanley, Crystal; Orme, Ian

    2014-01-01

    The global epidemic caused by the bacterial pathogen Mycobacterium tuberculosis continues unabated. Moreover, the only available vaccine against tuberculosis, Mycobacterium bovis bacillus Calmette-Guérin (BCG), demonstrates variable efficacy. To respond to this global threat, new animal models that mimic the pathological disease process in humans are required for vaccine testing. One new model, susceptible C3Heb/FeJ mice, is similar to human tuberculosis in that these animals are capable of forming necrotic tubercle granulomas, in contrast to resistant C3H/HeOuJ mice. In this study, we evaluated the impact of prior BCG vaccination of C3Heb/FeJ and C3H/HeOuJ mice on exposure to a low-dose aerosol of Mycobacterium tuberculosis W-Beijing strain SA161. Both BCG-vaccinated murine strains demonstrated reduced bacterial loads 25 days after infection compared to controls, indicating vaccine efficacy. However, during chronic infection, vaccine efficacy waned in C3H/HeOuJ but not in C3Heb/FeJ mice. Protection in vaccinated C3Heb/FeJ mice was associated with reduced numbers of CD11b+ Gr1+ cells, increased numbers of effector and memory T cells, and an absence of necrotic granulomas. BCG vaccine efficacy waned in C3H/HeOuJ mice, as indicated by reduced expression of gamma interferon (IFN-γ) and increased expressions of interleukin-17 (IL-17), IL-10, and Foxp3 by T cells compared to C3Heb/FeJ mice. This is the first murine vaccine model system described to date that can be utilized to dissect differential vaccine-derived immune efficacy. PMID:25392011

  20. Differential Mycobacterium bovis BCG vaccine-derived efficacy in C3Heb/FeJ and C3H/HeOuJ mice exposed to a clinical strain of Mycobacterium tuberculosis.

    PubMed

    Henao-Tamayo, Marcela; Obregón-Henao, Andrés; Creissen, Elizabeth; Shanley, Crystal; Orme, Ian; Ordway, Diane J

    2015-01-01

    The global epidemic caused by the bacterial pathogen Mycobacterium tuberculosis continues unabated. Moreover, the only available vaccine against tuberculosis, Mycobacterium bovis bacillus Calmette-Guérin (BCG), demonstrates variable efficacy. To respond to this global threat, new animal models that mimic the pathological disease process in humans are required for vaccine testing. One new model, susceptible C3Heb/FeJ mice, is similar to human tuberculosis in that these animals are capable of forming necrotic tubercle granulomas, in contrast to resistant C3H/HeOuJ mice. In this study, we evaluated the impact of prior BCG vaccination of C3Heb/FeJ and C3H/HeOuJ mice on exposure to a low-dose aerosol of Mycobacterium tuberculosis W-Beijing strain SA161. Both BCG-vaccinated murine strains demonstrated reduced bacterial loads 25 days after infection compared to controls, indicating vaccine efficacy. However, during chronic infection, vaccine efficacy waned in C3H/HeOuJ but not in C3Heb/FeJ mice. Protection in vaccinated C3Heb/FeJ mice was associated with reduced numbers of CD11b(+) Gr1(+) cells, increased numbers of effector and memory T cells, and an absence of necrotic granulomas. BCG vaccine efficacy waned in C3H/HeOuJ mice, as indicated by reduced expression of gamma interferon (IFN-γ) and increased expressions of interleukin-17 (IL-17), IL-10, and Foxp3 by T cells compared to C3Heb/FeJ mice. This is the first murine vaccine model system described to date that can be utilized to dissect differential vaccine-derived immune efficacy.

  1. Crystal Polymorphs of Barbital: News about a Classic Polymorphic System

    PubMed Central

    2013-01-01

    Barbital is a hypnotic agent that has been intensely studied for many decades. The aim of this work was to establish a clear and comprehensible picture of its polymorphic system. Four of the six known solid forms of barbital (denoted I0, III, IV, and V) were characterized by various analytical techniques, and the thermodynamic relationships between the polymorph phases were established. The obtained data permitted the construction of the first semischematic energy/temperature diagram for the barbital system. The modifications I0, III, and V are enantiotropically related to one another. Polymorph IV is enantiotropically related to V and monotropically related to the other two forms. The transition points for the pairs I0/III, I0/V, and III/IV lie below 20 °C, and the transition point for IV/V is above 20 °C. At room temperature, the order of thermodynamic stability is I0 > III > V > IV. The metastable modification III is present in commercial samples and has a high kinetic stability. The solid-state NMR spectra provide information on aspects of crystallography (viz., the asymmetric units and the nature of hydrogen bonding). The known correlation between specific N–H···O=C hydrogen bonding motifs of barbiturates and certain IR characteristics was used to predict the H-bonded pattern of polymorph IV. PMID:24283960

  2. Development of mRuby2-Transfected C3H10T1/2 Fibroblasts for Musculoskeletal Tissue Engineering

    PubMed Central

    Yang, Yunzhi Peter

    2015-01-01

    Mouse C3H10T1/2 fibroblasts are multipotent, mesenchymal stem cell (MSC)-like progenitor cells that are widely used in musculoskeletal research. In this study, we have established a clonal population of C3H10T1/2 cells stably-transfected with mRuby2, an orange-red fluorescence reporter gene. Flow cytometry analysis and fluorescence imaging confirmed successful transfection of these cells. Cell counting studies showed that untransfected C3H10T1/2 cells and mRuby2-transfected C3H10T1/2 cells proliferated at similar rates. Adipogenic differentiation experiments demonstrated that untransfected C3H10T1/2 cells and mRuby2-transfected C3H10T1/2 cells stained positive for Oil Red O and showed increased expression of adipogenic genes including adiponectin and lipoprotein lipase. Chondrogenic differentiation experiments demonstrated that untransfected C3H10T1/2 cells and mRuby2-transfected C3H10T1/2 cells stained positive for Alcian Blue and showed increased expression of chondrogenic genes including aggrecan. Osteogenic differentiation experiments demonstrated that untransfected C3H10T1/2 cells and mRuby2-transfected C3H10T1/2 cells stained positive for alkaline phosphatase (ALP) as well as Alizarin Red and showed increased expression of osteogenic genes including alp, ocn and osf-1. When seeded on calcium phosphate-based ceramic scaffolds, mRuby2-transfected C3H10T1/2 cells maintained even fluorescence labeling and osteogenic differentiation. In summary, mRuby2-transfected C3H10T1/2 cells exhibit mRuby2 fluorescence and showed little-to-no difference in terms of cell proliferation and differentiation as untransfected C3H10T1/2 cells. These cells will be available from American Type Culture Collection (ATCC; CRL-3268™) and may be a valuable tool for preclinical studies. PMID:26407291

  3. Development of mRuby2-Transfected C3H10T1/2 Fibroblasts for Musculoskeletal Tissue Engineering.

    PubMed

    Ker, Dai Fei Elmer; Sharma, Rashmi; Wang, Evelyna Tsi Hsin; Yang, Yunzhi Peter

    2015-01-01

    Mouse C3H10T1/2 fibroblasts are multipotent, mesenchymal stem cell (MSC)-like progenitor cells that are widely used in musculoskeletal research. In this study, we have established a clonal population of C3H10T1/2 cells stably-transfected with mRuby2, an orange-red fluorescence reporter gene. Flow cytometry analysis and fluorescence imaging confirmed successful transfection of these cells. Cell counting studies showed that untransfected C3H10T1/2 cells and mRuby2-transfected C3H10T1/2 cells proliferated at similar rates. Adipogenic differentiation experiments demonstrated that untransfected C3H10T1/2 cells and mRuby2-transfected C3H10T1/2 cells stained positive for Oil Red O and showed increased expression of adipogenic genes including adiponectin and lipoprotein lipase. Chondrogenic differentiation experiments demonstrated that untransfected C3H10T1/2 cells and mRuby2-transfected C3H10T1/2 cells stained positive for Alcian Blue and showed increased expression of chondrogenic genes including aggrecan. Osteogenic differentiation experiments demonstrated that untransfected C3H10T1/2 cells and mRuby2-transfected C3H10T1/2 cells stained positive for alkaline phosphatase (ALP) as well as Alizarin Red and showed increased expression of osteogenic genes including alp, ocn and osf-1. When seeded on calcium phosphate-based ceramic scaffolds, mRuby2-transfected C3H10T1/2 cells maintained even fluorescence labeling and osteogenic differentiation. In summary, mRuby2-transfected C3H10T1/2 cells exhibit mRuby2 fluorescence and showed little-to-no difference in terms of cell proliferation and differentiation as untransfected C3H10T1/2 cells. These cells will be available from American Type Culture Collection (ATCC; CRL-3268™) and may be a valuable tool for preclinical studies. PMID:26407291

  4. Partial characterization of a new C3-type capsule-dissolving phage of Streptococcus cremoris.

    PubMed

    Saxelin, M L; Nurmiaho, E L; Korhola, M P; Sundman, V

    1979-10-01

    A viscous, ropy, sour milk product, called 'viili,' is produced in Finland. Capsule-forming strains of Streptococcus cremoris are the typical starters for this product. Occasionally fermentation fails and results in a non-ropy clot. The reasons for these failures, however, are obscure. In one batch of spoiled 'viili,' a new C3-type bacteriophage, termed KSY1, was isolated. The head of the phage was about 230 nm long and about 50 nm wide and the tail was 35 nm long and carried a complex collar structure. Upon infection of a number of encapsulated cultures of S. cremoris with KSY1, the cocci, though not serving as a host of the phage, lost their capsules. A capsuleless strain, S. cremoris 249, served as a host. The latent period was about 150 min and the average burst size 80. The bouyant density of KSYI1 was 1.436 g/cm3.

  5. DFT study on the chemical sensitivity of C3N nanotubes toward acetone

    NASA Astrophysics Data System (ADS)

    Bagheri, Zargham

    2016-02-01

    Potential application of single-walled C3N nanotubes was investigated as chemical sensors for acetone molecules based on the density functional theory calculations. It was found that the pristine nanotube weakly adsorbs an acetone molecule with the adsorption energy of - 9.7 kcal/mol, and its electronic properties are not sensitive to this molecule. By replacing a C atom with a Si atom, the nanotube becomes a p-type semiconductor. The adsorption energy of the acetone molecule on the Si-doped nanotube becomes much more negative (Ead=-67.4 kcal/mol). The adsorption process leads to a sizable increase in the resistance of the Si-doped tube, thereby, it can show the presence of acetone molecule, creating an electronic signal. Also, the sensitivity of these devices can be controlled by the doping level of Si atoms. By increasing the number of dopant atoms from 1 to 4, the sensitivity is gradually increased.

  6. Carcinogenicity study of cochineal in B6C3F1 mice.

    PubMed

    Mori, H; Iwata, H; Tanaka, T; Morishita, Y; Mori, Y; Kojima, T; Okumura, A

    1991-09-01

    The carcinogenicity of cochineal, a red colouring used in food and other products, was studied in a 2-yr bioassay in B6C3F1 mice. Groups of 50-55 mice of each sex were given 0, 3 or 6% cochineal in the diet for 2 yr. Mice of all groups developed tumours including hepatocellular adenomas or carcinomas, pulmonary adenomas or adenocarcinomas and lymphomas or lymphatic leukaemias, and the incidences of these tumours were not significantly different in treated and control groups. The results indicate that cochineal lacks carcinogenicity in mice and are consistent with those of in vitro short-term assays of cochineal and of carminic acid, an active principle of cochineal. PMID:1937288