Sample records for alpha beta forms

  1. Recognition of base pair inversions in duplex by chimeric (alpha,beta) triplex-forming oligonucleotides.

    Timofeev, Edward N; Goryaeva, Baira V; Florentiev, Vladimir L


    DNA recognition by triplex-forming oligonucleotides (TFOs) is usually limited by homopurine-homopyrimidine sequence in duplexes. Modifications of the third strand may overcome this limitation. Chimeric alpha-beta TFOs are expected to form triplex DNA upon binding to non-regular sequence duplexes. In the present study we describe binding properties of chimeric alpha-beta oligodeoxynucleotides in the respect to short DNA duplexes with one, three, and five base pair inversions. Non-natural chimeric TFO's contained alpha-thymidine residues inside (GT) or (GA) core sequences. Modified residues were addressed to AT/TA inversions in duplexes. It was found in the non-denaturing gel-electrophoresis experiments that single or five adjacent base pair inversions in duplexes may be recognized by chimeric alpha-beta TFO's at 10 degrees C and pH 7.8. Three dispersed base pair inversions in the double stranded DNA prevented triplex formation by either (GT) or (GA) chimeras. Estimation of thermal stability of chimeric alpha-beta triplexes showed decrease in T(m) values as compared with unmodified complexes. PMID:16928141

  2. beta-Hexosaminidase isozymes from cells cotransfected with alpha and beta cDNA constructs: analysis of the alpha-subunit missense mutation associated with the adult form of Tay-Sachs disease.

    Brown, C. A.; Mahuran, D. J.


    In vitro mutagenesis and transient expression in COS cells has been used to associate a missense mutation with a clinical or biochemical phenotype. Mutations affecting the alpha-subunit of beta-hexosaminidase A (alpha beta) (E.C. result in Tay-Sachs disease. Because hexosaminidase A is heterodimeric, analysis of alpha-chain mutations is not straightforward. We examine three approaches utilizing previously identified mutations affecting alpha-chain folding. These involve transfection ...

  3. [beta]-hexosaminidase isozymes from cells cotransfected with [alpha] and [beta] cDNA constructs: Analysis of the [alpha]-subunit missense mutation associated with the adult form of Tay-Sachs disease

    Brown, C.A.; Mahuran, D.J. (Univ. of Toronto (Canada))


    In vitro mutagenesis and transient expression in COS cells has been used to associate a missense mutation with a clinical or biochemical phenotype. Mutations affecting the [alpha]-subunit of [beta]-hexosaminidase A ([alpha][beta]) (E.C. result in Tay-Sachs disease. Because hexosaminidase A is heterodimeric, analysis of [alpha]-chain mutations is not straightforward. The authors examine three approaches utilizing previously identified mutations affecting [alpha]-chain folding. These involve transfection of (1) the [alpha] cDNA alone; (2) a [beta] cDNA construct encoding a [beta]-subunit substituted at a position homologous to that of the [alpha]-subunit, and (3) both [alpha] and [beta] cDNAs. The latter two procedures amplified residual activity levels over that of patient samples, an effect not previously found with mutations affecting an [open quotes]active[close quotes] [alpha]Arg residue. This effect may help to discriminate between protein-folding and active-site mutations. The authors conclude that, with proper controls, the latter method of cotransfection can be used to evaluate the effects and perhaps to predict the clinical course of some [alpha]-chain mutations. Using this technique, they demonstrate that the adult-onset Tay-Sachs mutation, [alpha]Gly[yields]Ser[sup 269], does not directly affect [alpha][beta] dimerization but exerts an indirect effect on the dimer through destabilizing the folded [alpha]-subunit at physiological temperatures. Two other [alpha] mutations linked to more severe phenotypes appear to inhibit the initial folding of the subunit. 36 refs., 2 figs., 5 tabs.

  4. Monitor for alpha beta contamination of hands

    The following specifications of hands alpha beta contamination monitor are presented: the position of the hands, the detection and separation of alpha and beta, the information processing, the programming, the results presentation and general characteristics. (A.L.B.)

  5. From beta-relaxation to alpha-decay: Atomistic picture from molecular dynamics simulations for glass-forming Ni0.5Zr0.5 melt

    In glass-forming melts the decay of structural fluctuation shows the well known transition from beta-relaxation (von-Schweidler law with exponent b) to alpha-decay (KWW law with exponent beta). Here we present results from molecular dynamics simulations for a metallic glass forming Ni0.5Zr0.5 model aimed at giving an understanding of this transition on the atomistic scale. At the considered temperature below mode coupling Tc, the dynamics of the system can be interpreted by residence of the particles in their neighbour cages and escape from the cages as rare processes. Our analysis yields that the fraction of residing particles is characterized by a hierarchical law in time, with von-Schweidler b explicitly related to the exponent of this law. In the alpha-decay regime the stretching exponent reflects, in addition, floating of the cages due to strain effects of escaped particles. Accordingly, the change from beta-relaxation to alpha-decay indicates the transition from low to large fraction of escaped particles.

  6. A Trp474Cys mutation in the alpha-subunit of beta-hexosaminidase causes a subacute encephalopathic form of G{sub M2} gangliosidosis, type 1

    Petroulakis, E.; Cao, Z.; Salo, T. [Univ. of Manitoba, Winnipeg (Canada)] [and others


    Mutations in the HEXA gene that encodes the {alpha}-subunit of the heterodimeric lysosomal enzyme {beta}-hexosaminidase A, or Hex A ({alpha}{beta}), cause G{sub M2} gangliosidosis, type 1. The infantile form (Tay-Sachs disease) results when there is no residual Hex A activity, while less severe and more variable clinical phenotypes result when residual Hex A activity is present. A non-Jewish male who presented with an acute psychotic episode at age 16 was diagnosed with a subacute encephalopathic form of G{sub M2} gangliosidosis. At age 19, chronic psychosis with intermittent acute exacerbations remains the most disabling symptom in this patient and his affected brother although both exhibit some ataxia and moderately severe dysarthria. We have found a 4 bp insertion (+TATC 1278) associated with infantile Tay-Sachs disease on one allele; no previously identified mutation was found on the second allele. SSCP analysis detected a shift in exon 13 and sequencing revealed a G1422C mutation in the second allele that results in a Trp474Cys substitution. The presence of the mutation was confirmed by the loss of HaeIII and ScrFI sites in exon 13 PCR products from the subjects and their father. The mutation was introduced into the {alpha}-subunit cDNA and Hex S ({alpha}{alpha}) and Hex A ({alpha}{beta}) were transiently expressed in monkey COS-7 cells. The Trp474Cys mutant protein had approximately 5% and 12% of wild-type Hex S and Hex A activity, respectively. Western blot analysis revealed a small amount of residual mature {alpha}-subunit and a normal level of precursor protein. We conclude that the Trp474Cys mutation is the cause of the Hex A deficiency associated with a subacute (juvenile-onset) phenotype in this patient. Like other mutations in exon 13 of HEXA, it appears to affect intracellular processing. Studies of the defect in intracellular processing are in progress.

  7. Synthesis of beta-hexosaminidase in cell-free translation and in intact fibroblasts: an insoluble precursor alpha chain in a rare form of Tay-Sachs disease.

    Proia, R L; Neufeld, E F


    RNA was isolated from human term placenta or cultured fibroblasts and translated in a rabbit reticulocyte system in the presence of [35S]methionine; the translation products were immunoprecipitated with antisera made against beta-hexosaminidase or its isolated alpha and beta chains and analyzed by polyacrylamide gel electrophoresis. The largest translated alpha and beta chain polypeptides had Mrs of 65,000 and 59,000, respectively. These are approximately equal to 2,000 greater than the Mrs o...

  8. The Val{sup 192}Leu mutation in the {alpha}-subunit of {beta}-hexosaminidase A is not associated with the B1-variant form of Tay-Sachs disease

    Hou, Y.; Vavougios, G.; Hinek, A. [Univ. of Toronto (Canada)] [and others


    Substitution mutations adversely affecting the {alpha}-subunit of {beta}-hexosaminidase A ({alpha}{beta}) (EC result in Tay-Sachs disease. The majority affect the initial folding of the pro-{alpha} chain in the endoplasmic reticulum, resulting in its retention and degradation. A much less common occurrence is a mutation that specifically affects an {open_quotes}active-site{close_quotes} residue necessary for substrate binding and/or catalysis. In this case, hexosaminidase A is present in the lysosome, but it lacks all {alpha}-specific activity. This biochemical phenotype is referred to as the {open_quotes}B1-variant form{close_quotes} of Tay-Sachs disease. Kinetic analysis of suspected B1-variant mutations is complex because hexosaminidase A is heterodimeric and both subunits possess similar active sites. In this report, we examine a previously identified B1-variant mutation, {alpha}-Val{sup 192}Leu. Chinese hamster ovary cells were permanently cotransfected with an {alpha}-cDNA-construct encoding the substitution and a mutant {beta}-cDNA ({beta}-Arg{sup 211}Lys), encoding a {beta}-subunit that is inactive but normal in all other respects. We were surprised to find that the Val{sup 192}Leu substitution produced a pro-{alpha} chain that did not form {alpha}-{beta} dimers and was not transported to the lysosome. Finally, we reexamined the hexosaminidase activity and protein levels in the fibroblasts from the original patient. These data were also not consistent with the biochemical phenotype of the B1 variant of Tay-Sachs disease previously reported to be present. Thus, we conclude that the Val{sup 192}Leu substitution does not specifically affect the {alpha}-active site. 23 refs., 4 figs., 2 tabs.

  9. The monomeric alpha beta form of the insulin receptor exhibits much higher insulin-dependent tyrosine-specific protein kinase activity than the intact alpha 2 beta 2 form of the receptor.

    Fujita-Yamaguchi, Y; Kathuria, S.


    The relationship between the structure of the insulin receptor and its kinase activity was studied on the purified receptor treated with different concentrations of dithiothreitol. An enhanced autophosphorylation of the beta subunit (Mr, 90,000) was observed on NaDodSO4/PAGE under reducing conditions when the receptor was treated with 0.1-0.75 mM dithiothreitol in the presence of 1 microM insulin. Since we have previously observed (unpublished data) that incubation of the purified receptor wi...

  10. Thermodynamics in $f(R,R_{\\alpha\\beta}R^{\\alpha\\beta},\\phi)$ theory of gravity

    Zubair, M; Bahamonde, Sebastian


    First and second laws of black hole thermodynamics are examined at the apparent horizon of FRW spacetime in $f(R,R_{\\alpha\\beta}R^{\\alpha\\beta} ,\\phi)$ gravity, where $R$, $R_{\\alpha\\beta}$ and $\\phi$ are the Ricci scalar, Ricci invariant and the scalar field respectively. In this modified theory, Friedmann equations are formulated for any spatial curvature. These equations can be presented into the form of first law of thermodynamics $T_{h}d\\hat{S}_{h}+ T_{h}d_{i}\\hat{S}_{h}+W dV=dE$, where $d_{i}\\hat{S}_{h}$ is an extra entropy term because of the non-equilibrium presentation of the equations. The generalized second law of thermodynamics (GSLT) is expressed in an inclusive form where these results can be represented, in GR, $f(R)$ and $f(R, \\phi)$ gravities. Finally to check the validity of GSLT, we take some particular models and produce constraints of the parameters.

  11. Cosmological reconstruction and energy bounds in $f(R,R_{\\alpha \\beta}R^{\\alpha\\beta},\\phi)$ gravity

    Zubair, M


    We discuss the cosmological reconstruction of $f(R,R_{\\alpha\\beta}R^{\\alpha\\beta},\\phi)$ (where $R$, $R_{\\alpha\\beta}R^{\\alpha\\beta}$ and $\\phi$ represents the Ricci scalar, Ricci invariant and scalar field) corresponding to power law and de Sitter evolution in the framework of FRW universe model. We derive the energy conditions for this modified theory which seem to be more general and can be reduced to some known forms of these conditions in general relativity, $f(R)$ and $f(R,\\phi)$ theories. We have presented the general constraints in terms of recent values of snap, jerk, deceleration and Hubble parameters. The energy bounds are analyzed for reconstructed as well as known models in this theory. Finally, the free parameters are analyzed comprehensively.

  12. Alpha-globin loci in homozygous beta-thalassemia intermedia.

    Triadou, P; Lapoumeroulie, C; Girot, R; Labie, D


    Homozygous beta-thalassemia intermediate (TI) differs from thalassemia major (TM) in being less severe clinically. Associated alpha-thalassemia could account for the TI phenotype by reducing the alpha/non-alpha chain imbalance. We have analyzed the alpha loci of 9 TI and 11 TM patients by restriction endonuclease mapping. All the TM and 7 of the TI patients have the normal complement of four alpha-globin genes (alpha alpha/alpha alpha). One TI patient has three alpha-globin genes (alpha alpha/-alpha), and another TI patient has five alpha genes (alpha alpha/alpha alpha alpha). PMID:6305827

  13. Smart Beta or Smart Alpha

    Winther, Kenneth Lillelund; Steenstrup, Søren Resen


    that smart beta investing probably will do better than passive market capitalization investing over time, we believe many are coming to a conclusion too quickly regarding active managers. Institutional investors are able to guide managers through benchmarks and risk frameworks toward the same well...... only superior to the common capitalization weighted index but also to their smart beta benchmark, even after cost for value, size, and low volatility funds. We encourage investors to increase the use of smart beta as benchmarks while still obtaining extra performance through active management—a concept...

  14. Rare-earth doped (alpha'/beta')-sialon ceramics

    Gajum, N R


    combination of light and heavy rare-earth (Yb-Nd and Gd-Nd), and then pressureless sintered and compared with the single cation materials. Materials in the as sintered state were composed of a high alpha' sialon content with a minor amount of beta' sialon and 12H A1N polytype indicating that the heavy rare-earth (which is the principal alpha' stabilizer) has a dominant effect although EDAX analysis confirmed the presence of both cations (light and heavy) within the alpha' structure. The research also compared, and developed an understanding of, the thermal stability of alpha'-sialon using single Yb or mixed cations. The Yb single cation alpha'/beta' materials exhibited excellent stability over a range of temperature (1200 - 1600 deg C) and for different periods of time up to 168 hrs. The heat treatments result in the crystallisation of the residual phase as a Yb garnet phase which formed at approx 1300 deg C. The mixed cation alpha'/beta' materials showed some alpha'-beta' transformation. The transformation w...

  15. Osmotic fragility test in heterozygotes for alpha and beta thalassaemia.

    Maccioni, L; Cao, A


    This study shows that the combination of heterozygous beta thalassaemia and deletion heterozygous (-alpha/alpha alpha) or homozygous (-alpha/-alpha) alpha+ thalassaemia may result in the production of erythrocytes which have normal mean volume and haemoglobinisation but decreased osmotic fragility. Based on this finding and previous studies, which have shown that beta thalassaemia screening by the osmotic fragility test may miss a significant proportion of beta thalassaemia heterozygotes, we ...

  16. HPLC/1H NMR spectroscopic studies of the reactive alpha-1-O-acyl isomer formed during acyl migration of S-naproxen beta-1-O-acyl glucuronide.

    Corcoran, O; Mortensen, R W; Hansen, S H; Troke, J; Nicholson, J K


    A widely held view in drug metabolism and pharmacokinetic studies is that the initial 1-isomer to 2-isomer step in the intramolecular acyl migration of drug ester glucuronides is irreversible, and that alpha-1-O-acyl isomers do not occur under physiological conditions. We investigated this hypothesis using high-performance liquid chromatography directly coupled to proton nuclear magnetic resonance spectroscopy (HPLC/1H NMR) and mass spectrometry (LC/MS) to probe the migration reactions of S-naproxen beta-1-O-acyl glucuronide, in phosphate buffer at pH 7.4, 37 degrees C. We report the first direct observation of the alpha-1-O-acyl isomer of a drug ester glucuronide (S-naproxen) formed in a biosystem via the facile acyl migration of the corresponding pure beta-1-O-acyl glucuronide. The unequivocal identification of the reactive product was achieved using stopped-flow one-dimensional HPLC/1H NMR and two-dimensional 1H-1H total correlation spectroscopy (1H-1H TOCSY). Parallel LC/ion-trap mass spectrometry yielded the confirmatory glucuronide masses. Moreover, "dynamic" stopped-flow HPLC/1H NMR experiments revealed transacylation of the isolated alpha-1-O-acyl isomer to a mixture of alpha/beta-2-O-acyl isomers; the reverse reaction from the isolated alpha/beta-2-O-acyl isomers to the alpha-1-O-acyl isomer was also clearly demonstrated. This application of "dynamic" stopped-flow HPLC/1H NMR allows key kinetic data to be obtained on a reactive metabolite that would otherwise be difficult to follow by conventional HPLC and NMR methods where sample preparation and off-line separations are necessary. These data challenge the widely held view that the alpha-1-O-acyl isomers of drug ester glucuronides do not occur under physiological conditions. Furthermore, the similar formation of alpha-1-O-acyl isomers from zomepirac and diflunisal beta-1-O-acyl glucuronides has recently been confirmed (Corcoran et al., unpublished results). Such reactions are also likely to be widespread

  17. Source preparations for alpha and beta measurements

    Holm, E. [Risoe National Lab., Roskilde (Denmark)


    Regarding alpha particle emitters subject for environmental studies, electrodeposition or co-precipitation as fluorides are the most common methods. For electro deposition stainless steel is generally used as cathode material but also other metals such as Ni, Ag, and Cu showed promising results. The use of other anode material than platinum, such as graphite should be investigated. For other purposes such as optimal resolution other more sophisticated methods are used but often resulting in poorer recovery. For beta particle emitters the type of detection system will decide the source preparation. Similar methods as for alpha particle emitters, electrodeposition or precipitation techniques can be used. Due to the continuous energy distribution of the beta pulse height distribution a high resolution is not required. Thicker sources from the precipitates or a stable isotopic carrier can be accepted but correction for absorption in the source must be done. (au)

  18. Source preparations for alpha and beta measurements

    Regarding alpha particle emitters subject for environmental studies, electrodeposition or co-precipitation as fluorides are the most common methods. For electro deposition stainless steel is generally used as cathode material but also other metals such as Ni, Ag, and Cu showed promising results. The use of other anode material than platinum, such as graphite should be investigated. For other purposes such as optimal resolution other more sophisticated methods are used but often resulting in poorer recovery. For beta particle emitters the type of detection system will decide the source preparation. Similar methods as for alpha particle emitters, electrodeposition or precipitation techniques can be used. Due to the continuous energy distribution of the beta pulse height distribution a high resolution is not required. Thicker sources from the precipitates or a stable isotopic carrier can be accepted but correction for absorption in the source must be done. (au)

  19. Integrins (alpha7beta1) in muscle function and survival. Disrupted expression in merosin-deficient congenital muscular dystrophy

    Vachon, P H; Xu, H; Liu, L;


    Mutations in genes coding for dystrophin, for alpha, beta, gamma, and delta-sarcoglycans, or for the alpha2 chain of the basement membrane component merosin (laminin-2/4) cause various forms of muscular dystrophy. Analyses of integrins showed an abnormal expression and localization of alpha7beta1...

  20. Synthesis of a precursor for the preparation of 9 alpha,11 alpha-tritiated 5 alpha-androstane-3 alpha,17 beta-diol 17-glucuronide

    Starting from 11 beta-hydroxytestosterone, the synthesis of a strategic precursor, C-9 (11) unsaturated 5 alpha-androstane-3 alpha, 17 beta-diol 17-glucuronide (9a), for the preparation of 9 alpha,11 alpha-tritiated 5 alpha-androstane-3 alpha, 17 beta-diol 17-glucuronide has been achieved. The authors optimized the reaction conditions for catalytic reduction employing hydrogen and subsequent base hydrolysis followed by purification on Amberlite XAD-2 resin to obtain the saturated 5 alpha-androstane-3 alpha, 17 beta-diol 17-glucuronide

  1. Development of a three-layer phoswich alpha-beta-gamma imaging detector

    Yamamoto, Seiichi; Ishibashi, Hiroyuki


    For radiation monitoring at the sites of such nuclear power plant accidents as Fukushima Daiichi, radiation detectors are needed not only for gamma photons but also for alpha and beta particles because some nuclear fission products emit beta particles and gamma photons and some nuclear fuels contain plutonium that emits alpha particles. In some applications, imaging detectors are required to detect the distribution of plutonium particles that emit alpha particles and radiocesium in foods that emits beta particles and gamma photons. To solve these requirements, we developed an imaging detector that can measure the distribution of alpha and beta particles as well as gamma photons. The imaging detector consists of three-layer scintillators optically coupled to each other and to a position sensitive photomultiplier tube (PSPMT). The first layer, which is made of a thin plastic scintillator (decay time: ~5 ns), detects alpha particles. The second layer, which is made of a thin Gd2SiO5 (GSO) scintillator with 1.5 mol% Ce (decay time: 35 ns), detects beta particles. The third layer made of a thin GSO scintillator with 0.4 mol% Ce (decay time: 70 ns) detects gamma photons. Using pulse shape discrimination, the images of these layers can be separated. The position information is calculated by the Anger principle from 8×8 anode signals from the PSPMT. The images for the alpha and beta particles and the gamma photons are individually formed by the pulse shape discriminations for each layer. We detected alpha particle images in the first layer and beta particle images in the second layer. Gamma photon images were detected in the second and third layers. The spatial resolution for the alpha and beta particles was ~1.25 mm FWHM and less than 2 mm FWHM for the gamma photons. We conclude that our developed alpha-beta-gamma imaging detector is promising for imaging applications not only for the environmental monitoring of radionuclides but also for medical and molecular imaging.

  2. Isolation and characterization of recombinant human casein kinase II subunits alpha and beta from bacteria

    Grankowski, N; Boldyreff, B; Issinger, O G


    cDNA encoding the casein kinase II (CKII) subunits alpha and beta of human origin were expressed in Escherichia coli using expression vector pT7-7. Significant expression was obtained with E. coli BL21(DE3). The CKII subunits accounted for approximately 30% of the bacterial protein; however, most...... of the expressed proteins were produced in an insoluble form. The recombinant CKII alpha subunit was purified by DEAE-cellulose chromatography, followed by phosphocellulose and heparin-agarose chromatography. The recombinant CKII beta subunit was extracted from the insoluble pellet and purified in a...... single step on phosphocellulose. From 10 g bacterial cells, the yield of soluble protein was 12 mg alpha subunit and 5 mg beta subunit. SDS/PAGE analysis of the purified recombinant proteins indicated molecular masses of 42 kDa and 26 kDa for the alpha and beta subunits, respectively, in agreement with...

  3. Biodegradable films containing {alpha}-tocopherol/{beta}-cyclodextrin complex; Filmes biodegradaveis contendo {alpha}-tocoferol complexado em {beta}-ciclodextrina

    Motta, Caroline; Martelli, Silvia M.; Soldi, Valdir, E-mail: [Lab. de Materiais Polimericos (POLIMAT), Dept. de Quimica, Universidade Federal de Santa Catarina, Florianopolis, SC (Brazil); Barreto, Pedro L.M. [Lab. de Reologia (REOLAB), Dept. de Ciencia e Tecnologia de Alimentos, Universidade Federal de Santa Catarina, Florianopolis, SC (Brazil)


    The growing environmental concern about pollution and the need to reduce dependence of plastic industry in relation to non-renewable resources has increased the interest of both researchers and industry in the use of biopolymers. In this work {beta}-cyclodextrin/{alpha}-tocopherol complexes were prepared and characterized. In order to obtain polymeric active biofilms, the {beta}-cyclodextrin/{alpha}-tocopherol complex was incorporated into a polymeric matrix of carboxymethylcellulose. The {beta}-cyclodextrin/{alpha}-tocopherol complex was characterized through of X-ray diffraction and thermogravimetric analysis. The physicochemical properties of the films incorporated with the complex were evaluated through mechanical and colorimetric analysis and moisture sorption isotherm. (author)

  4. Sources of Alpha and Beta in Property Funds

    Baum, Andrew; Farrelly, Kieran


    This paper examines issues related to potential analytical performance systems for global property funds. These will include traditional attribution methods but will also cover the performance concepts of alpha and beta widely used in other asset classes. We look at issues including...what creates beta, and what drives alpha in real estate investment? How can it be measured and isolated? How do these concepts relate to traditional attribution systems? Can performance records and performanc...

  5. Properly formed but improperly localized synaptic specializations in the absence of laminin alpha4.

    Patton, B L; Cunningham, J M; Thyboll, J; Kortesmaa, J; Westerblad, H; Edström, L; Tryggvason, K; Sanes, J R


    Precise apposition of pre- to postsynaptic specializations is required for optimal function of chemical synapses, but little is known about how it is achieved. At the skeletal neuromuscular junction, active zones (transmitter release sites) in the nerve terminal lie directly opposite junctional folds in the postsynaptic membrane. Few active zones or junctional folds form in mice lacking the laminin beta2 chain, which is normally concentrated in the synaptic cleft. beta2 and the broadly expressed gamma1 chain form heterotrimers with alpha chains, three of which, alpha2, alpha4 and alpha5, are present in the synaptic cleft. Thus, alpha2beta2gamma1, alpha4beta2gamma1 and alpha5beta2gamma1 heterotrimers are all lost in beta2 mutants. In mice lacking laminin alpha4, active zones and junctional folds form in normal numbers, but are not precisely apposed to each other. Thus, formation and localization of synaptic specializations are regulated separately, and alpha4beta2gamma1 (called laminin-9) is critical in the latter process. PMID:11369940

  6. Integrin {alpha}{beta}1, {alpha}{sub v}{beta}, {alpha}{sub 6}{beta} effectors p130Cas, Src and talin regulate carcinoma invasion and chemoresistance

    Sansing, Hope A. [Department of Oral and Craniofacial Biology, Louisiana State University Health Sciences Center-New Orleans, School of Dentistry, New Orleans, LA (United States); Sarkeshik, Ali; Yates, John R. [Department of Chemical Physiology, Scripps Research Institute, La Jolla, CA (United States); Patel, Vyomesh; Gutkind, J. Silvio [Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States); Yamada, Kenneth M. [Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States); Berrier, Allison L., E-mail: [Department of Oral and Craniofacial Biology, Louisiana State University Health Sciences Center-New Orleans, School of Dentistry, New Orleans, LA (United States)


    Research highlights: {yields} Proteomics of clustered integrin {alpha}{beta}1, {alpha}{sub v}{beta}, {alpha}{sub 6}{beta} receptors in oral carcinoma. {yields} p130Cas, Dek, Src and talin regulate oral carcinoma invasion. {yields} p130Cas, talin, Src and zyxin regulate oral carcinoma resistance to cisplatin. -- Abstract: Ligand engagement by integrins induces receptor clustering and formation of complexes at the integrin cytoplasmic face that controls cell signaling and cytoskeletal dynamics critical for adhesion-dependent processes. This study searches for a subset of integrin effectors that coordinates both tumor cell invasion and resistance to the chemotherapeutic drug cisplatin in oral carcinomas. Candidate integrin effectors were identified in a proteomics screen of proteins recruited to clustered integrin {alpha}{beta}1, {alpha}{sub v}{beta} or {alpha}{sub 6}{beta} receptors in oral carcinomas. Proteins with diverse functions including microtubule and actin binding proteins, and factors involved in trafficking, transcription and translation were identified in oral carcinoma integrin complexes. Knockdown of effectors in the oral carcinoma HN12 cells revealed that p130Cas, Dek, Src and talin were required for invasion through Matrigel. Disruption of talin or p130Cas by RNA interference increased resistance to cisplatin, whereas targeting Dek, Src or zyxin reduced HN12 resistance to cisplatin. Analysis of the spreading of HN12 cells on collagen I and laminin I revealed that a decrease in p130Cas or talin expression inhibited spreading on both matrices. Interestingly, a reduction in zyxin expression enhanced spreading on laminin I and inhibited spreading on collagen I. Reduction of Dek, Src, talin or zyxin expression reduced HN12 proliferation by 30%. Proliferation was not affected by a reduction in p130Cas expression. We conclude that p130Cas, Src and talin function in both oral carcinoma invasion and resistance to cisplatin.

  7. Dynamic expression of alpha 1 beta 1 and alpha 2 beta 1 integrin receptors by human vascular smooth muscle cells. Alpha 2 beta 1 integrin is required for chemotaxis across type I collagen-coated membranes.

    Skinner, M P; Raines, E W; Ross, R.


    Vascular smooth muscle cells (SMCs) in the media of normal arteries express alpha 1 beta 1 integrin with no detectable alpha 2 beta 1 as determined by immunocytochemistry. In contrast, immunoprecipitation of integrins expressed by human SMCs cultured from medial explants shows strong expression of alpha 2 beta 1 and no expression of alpha 1 beta 1. The apparent reciprocal expression of these two collagen and laminin receptors was confirmed by flow cytometric analysis of fluorescent labeled ce...

  8. Improved targeting of the alpha(v)beta (3) integrin by multimerisation of RGD peptides.

    Dijkgraaf, I.; Kruijtzer, J.A.; Liu, S.; Soede, A.C.; Oyen, W.J.G.; Corstens, F.H.M.; Liskamp, R.M.; Boerman, O.C.


    PURPOSE: The integrin alpha(v)beta(3) is expressed on sprouting endothelial cells and on various tumour cell types. Due to the restricted expression of alpha(v)beta(3) in tumours, alpha(v)beta(3) is considered a suitable receptor for tumour targeting. In this study the alpha(v)beta(3) binding charac

  9. Constitution of pseudobinary hypoeutectic beta-NiAl + alpha-V alloys

    Cotton, J. D.; Kaufman, M. J.; Noebe, R. D.


    The formation of pseudobinary eutectics between NiAl (beta) and V (alpha) at high temperatures was investigated as a possible way of improving the ductility and toughness of the alloy. It is found that a pseudobinary eutectic, characterized by a large beta+alpha field, is formed in the Ni-Al-V ternary system below about 1370 C. The high-temperature solubility of V in beta is about 14 percent, decreasing markedly with decreasing temperature and increasing Al content above 50 at. pct Al. The pseudobinary hypoeutectic exibits crack resistance under indentation loading.

  10. Expression of interleukin-2R alpha and interleukin-2R beta in Hodgkin's disease.

    Tesch, H.; A. Günther; Abts, H.; Jücker, M; Klein, S; Krueger, G. R.; Diehl, V.


    Hodgkin and Reed-Sternberg cells, the putative malignant cells of Hodgkin's disease (HD), carry regularly the CD25 antigen that forms one chain of the interleukin-2 (IL-2) receptor (IL-2R alpha). To analyze the putative role of IL-2R expression in Hodgkin's disease, we have investigated the expression of both IL-2R alpha and IL-2R beta chains in HD-derived cell lines and in primary specimens from patients with HD. Expression of IL-2R alpha and IL-2R beta was detected in all HD-derived cell li...

  11. Alpha Beta Monitoring System Based on a Pair of Simultaneous Multi Wire Proportional Counters

    A new approach for a simultaneous alpha beta contamination monitoring system is presented. In nuclear environments or laboratories working with open radioactive sources there exists a risk of contamination. In order to avoid external contamination hazards, hand & foot alpha beta monitoring systems are needed. Usually, monitoring systems are based on large area Multi Wire Proportional Counters (MWPC).Generally, in the MWPC detectors the filling gas is supplied by a continuous gas supply system. The filling gas should not exhibit appreciable electron attachment coefficient. Typically, a noble gas such as Argon Methane, 90%Ar+10%CH4 is in use. This method of measurement is effective, yet it requires expensive maintenance costs due to gas flow control and periodical replacements. Several hand held commercial detectors such as Rotem Ind. PA-100, are based on free air flow alpha MWPC. Due to the energy released from the alpha particles in the filling gas a large number of ion pairs are formed. Despite the electron attachment coefficient of free air, a measurable pulse is obtained. Contrary to alpha sources, beta emitters deposit only a small part of their energy. In order to obtain a measurable pulse from beta interactions, oxygen free gas is required. Gas sealed detectors which are appropriate for beta measurements, require a relative thick entrance window in order to avoid gas leakage. Thick windows absorb alpha particles so that they are not appropriate for alpha measurement. The presented approach combines a pair of simultaneous MWPC assembled in a ôpancakeö type configuration; the sealed gas beta counter is located behind a free air alpha detector. This approach enables simultaneous alpha-beta measurement without needing continuous gas supply

  12. Pressure phase lines and enthalpies for the. cap alpha. -. beta. and. beta. -liquid transitions in beryllium

    Abey, A.


    The effect of hydrostatic pressure on the ..cap alpha..-..beta.. and ..beta..-liquid transition temperatures in Be was measured in a gas pressure system. Differential thermal analysis was used in the pressure range from 0.1 MPa to 0.7 GPa. For the ..cap alpha..-..beta.. transition, dT/dP = 43 +- 7 K/GPa; for the ..beta..-liquid transition, dT/dP = 35 +- 7 K/GPa. Although it is possible that large systematic errors may arise from experimental procedures, our results are seriously at odds with those of other investigators. Transition enthalpies for the ..cap alpha..-..beta.. and ..beta..-liquid transitions were 1.9 +- 0.2 and 2.2 +- 0.2 kcal/g.m., respectively, at a pressure of 0.1 MPa.

  13. Biotransformation of alpha- and 6beta-santonin by fungus and plant cell cultures.

    Yang, L; Dai, J; Sakai, J-I; Ando, M


    One fungus, Abisidia coerulea IFO 4011, and suspended cell cultures of one plant, Asparagus officinalis, were employed to bioconvert alpha- and 6beta-santonin. Incubation of alpha-santonin with the cell cultures of the fungus afforded two products, 11beta-hydroxy-alpha-santonin (1, in 76.5% yield) and 8alpha-hydroxy-alpha-santonin (2, in 2.0% yield). And from 6beta-santonin, four major products (3, 4, 5 and 6) and four minor products (7, 8, 9 and 10) were obtained, including 8alpha-hydroxylated products in trace yields. Very interestingly, a skeletal rearrangement occurred and a guaiane product (13) formed in a very low yield when alpha-santonin incubating with A.officinalis cell cultures, while not in the case of 6beta-santonin as substrate. Among the obtained 15 products, 2, 7, 8, 9, 10 and 12 are new compounds. The fact of 8alpha hydroxylation of santonin enables the formation of 8,12-eudesmanolide instead of 6,12-eudesmanolide and some useful modification at C-8 position. In addition, these reactions would provide evidence for the biogenesis between different types of eudesmane and/or guaiane compounds in the plants in nature. PMID:16864442

  14. Radioligands for imaging myocardial {alpha}- and β-adrenoceptors

    Riemann, B.; Schaefers, M.; Schober, O. [Dept. of Nuclear Medicine, Muenster Univ. (Germany); Law, M.P. [MRC Clinical Sciences Centre, Imperial Coll. School of Science, Technology and Medicine, Hammersmith Hospital, London (United Kingdom); Wichter, T. [Dept. of Cardiology and Angiology, Muenster Univ. (Germany)


    Alpha- and beta-adrenoceptors play an important role in the control of heart function. According to their molecular, biological, and pharmacological characteristics, they are subdivided into {alpha}{sub 1}-, {alpha}{sub 2}- and β{sub 1}-, β{sub 2}-, β{sub 3}-, β{sub 4}- adrenoceptors. In cardiac disease, there is often a selective downregulation of β{sub 1}-adrenoceptors associated with a relative increase in β{sub 2}- and {alpha}{sub 1}-adrenoceptors. Functional imaging techniques like single-photon emission tomography (SPECT) and positron emission tomography (PET) provide the unique capability for non-invasive assessment of cardiac adrenoceptors. Radioligands with high specific binding to cardiac {alpha}- and β-adrenoceptors suitable for radiolabelling are required for clinical studies. The non-selective β-adrenoceptor antagonist [{sup 11}C]CGP-12177 was used to quantify β-adrenoceptor density using PET in patients with heart disease. New non-selective ligands (e. g. [{sup 11}C]CGP-12388, [{sup 18}F]CGP-12388, [{sup 11}C]carazolol and [{sup 18}F]fluorocarazolol) are currently evaluated; β{sub 1}-selective radioligands (e. g. [{sup 11}C]CGP-26505, [{sup 11}C]bisoprolol, [{sup 11}C]HX-CH 44) and β{sub 2}-selective radioligands (e. g. [{sup 11}C]formoterol, [{sup 11}C]ICI-118551) were assessed in animals. None of them turned out as suitable for cardiac PET. Potential radioligands for imaging cardiac {alpha}{sub 1}-adrenoceptors are based on prazosin. Whereas [{sup 11}C]prazosin shows low specific binding to myocardium, its derivative [{sup 11}C]GB67 looks more promising. The putative {alpha}{sub 2}-adrenoceptor radioligand [{sup 11}C]MK-912 shows high uptake in rodent myocardium but has not yet been evaluated in man. A number of radioligands were evaluated for assessing cardiac adrenoceptors using PET. New radioligands are needed to provide more insight into cardiac pathophysiology which may influence the

  15. Low-Temperature Forming of Beta Titanium Alloys

    Kaneko, R. S.; Woods, C. A.


    Low cost methods for titanium structural fabrication using advanced cold-formable beta alloys were investigated for application in a Mach 2.7 supersonic cruise vehicle. This work focuses on improving processing and structural efficiencies as compared with standard hot formed and riveted construction of alpha-beta alloy sheet structure. Mechanical property data and manufacturing parameters were developed for cold forming, brazing, welding, and processing Ti-15V-3Cr-3Sn-3Al sheet, and Ti-3Al-8V-6Cr-4Zr on a more limited basis. Cost and structural benefits were assessed through the fabrication and evaluation of large structural panels. The feasibility of increasing structural efficiency of beta titanium structure by selective reinforcement with metal matrix composite was also explored.

  16. Synthesis of plastic scintillation microspheres: Alpha/beta discrimination

    Plastic scintillation microspheres (PSm) have been developed as an alternative for liquid scintillation cocktails due to their ability to avoid the mixed waste, besides other strengths in which the possibility for alpha/beta discrimination is included. The aim of this work was to evaluate the capability of PSm containing two combinations of fluorescence solutes (PPO/POPOP and pT/Bis-MSB) and variable amounts of a second organic solvent (naphthalene) to enhance the alpha/beta discrimination. Two commercial detectors with different Pulse Shape Discrimination performances (Quantulus and Triathler) were used to evaluate the alpha/beta discrimination. An optimal discrimination of alpha/beta particles was reached, with very low misclassification values (2% for beta particles and 0.5% for alpha particles), when PSm containing PPO/POPOP and between 0.6 and 2.0 g of naphthalene were evaluated using Triathler and the appropriate programme for data processing. - Highlights: • Plastic scintillation microspheres for α/β discrimination have been synthesised. • The energy transfer process in PSm with different compositions has been investigated. • The α/β discrimination capabilities of two commercial detectors have been evaluated. • 2% and 0.5% of misclassifications for β and α radionuclides have been achieved respectively

  17. Alpha and beta dose gradients in tooth enamel

    New results describing gradients in effective alpha and beta doses within a layer of tooth enamel in planar geometry are presented. The alpha (track) dose to an enamel layer is calculated using an algorithm similar to that of Aitken (Aitken, M.J., 1987. Alpha dose to a thin layer. Ancient TL 5, 1-3.). The code for ROSY version 1.4 incorporates this algorithm. The approach allows for variation of the alpha track dose near the edges of the enamel, and we describe the gradient of the alpha track dose within 40 μm of each edge of the enamel for natural sources. In ESR or luminescence dating of naturally thin layers, for which stripping of the surface layer containing the alpha dose gradients may not be feasible, age estimates may change by as much as 5-10% when the detailed alpha dose calculation is included. Modern Monte Carlo-based results for the variation of beta dose for depths up to 2 mm are compared with ROSY results. For external irradiation by different sources, the attenuation of the ROSY dose estimate with depth is usually less rapid than that of the Monte Carlo-based estimate. The ROSY estimate of average beta dose to a layer in this case is between 5 and 18% higher than the Monte Carlo estimate

  18. The Val192Leu mutation in the alpha-subunit of beta-hexosaminidase A is not associated with the B1-variant form of Tay-Sachs disease.

    Hou, Y; Vavougios, G.; Hinek, A.; Wu, K. K.; Hechtman, P; Kaplan, F; Mahuran, D. J.


    Substitution mutations adversely affecting the alpha-subunit of beta-hexosaminidase A (alphabeta) (EC result in Tay-Sachs disease. The majority affect the initial folding of the pro-alpha chain in the endoplasmic reticulum, resulting in its retention and degradation. A much less common occurrence is a mutation that specifically affects an "active-site" residue necessary for substrate binding and/or catalysis. In this case, hexosaminidase A is present in the lysosome, but it lacks al...

  19. Infrared spectra of olivine polymorphs - Alpha, beta phase and spinel

    Jeanloz, R.


    The infrared absorption spectra of several olivines (alpha phase) and their corresponding beta phase (modified spinel) and spinel (gamma) high-pressure polymorphs are determined. Spectra were measured for ground and pressed samples of alpha and gamma A2SiO4, where A = Fe, Ni, Co; alpha and gamma Mg2GeO4; alpha Mg2SiO4; and beta Co2SiO4. The spectra are interpreted in terms of internal, tetrahedral and octagonal, and lattice vibration modes, and the spinel results are used to predict the spectrum of gamma Mg2SiO4. Analysis of spectra obtained from samples of gamma Mg2GeO4 heated to 730 and 1000 C provides evidence that partial inversion could occur in silicate spinels at elevated temperatures and pressures.

  20. Phoswich Detector for Simultaneous Measuring Alpha/beta Particles

    The new type phoswich detector consisting of the ZnS(Ag) and plastic scintillator for alpha/beta-ray simultaneous counting was developed for monitoring radiological contamination inside pipes. The detection performance was estimated using the PSD (pulse shape discrimination) method as a function of distance between the scintillator and radioactive source. The attenuation of particles traveling through a thin film for preventing the detector from being contaminated was experimentally estimated. It is concluded from our investigation that the phoswich detector developed can provide a sufficient alpha/beta-ray discrimination. The application of a thin film for preventing the detector from being contaminated was proven to be feasible.

  1. The H-alpha/H-beta ratio in solar flares

    Zirin, H.; Liggett, M.; Patterson, A.


    The present investigation involves the study of an extensive body of data accumulated of simultaneous H-alpha and H-beta cinematography of flares. The data were obtained with two telescopes simultaneously photographing flares in H-alpha and H-beta. The results of measurements in a number of flares are presented in a table. The flares were selected purely by optical quality of the data. That the measured ratios are not too different from those in stellar flares is suggested by the last two columns of the table. These columns show that a variety of possible line width ratios could give an integrated intensity ratio of less than unity.

  2. Alpha-beta discrimination in LENA

    Alpha emitting isotopes, mainly 210Po, provide a background for the detection of 7Be neutrinos in LENA (Low Energy Neutrino Astronomy). This background can be reduced by a pulse shape analysis, as alpha particles and electrons have a different typical pulse shape, caused by the different energy deposition per unit path length ((dE)/(dx)). Thus, the efficiency of this method was analyzed by a detailed Monte Carlo study. Several scintillators as well as the influence of the photomultiplier performance on the discrimination efficiency were investigated.

  3. Chondroitin sulphate modification in the alpha4 chain of human recombinant laminin-8 (alpha4beta1gamma1).

    Kortesmaa, Jarkko; Doi, Masayuki; Patarroyo, Manuel; Tryggvason, Karl


    We have produced human laminin-8 (alpha4beta1gamma1) using recombinant technology. Approximately half of the recombinant laminin-8 (rLN-8) molecules were found to have a chondroitin sulphate modification in the alpha4 chain. The substituted and non-substituted forms were separated and tested for cell adhesion activity. Lower cell adhesion promoting activity was seen for the substituted form, but the integrin receptor utilization was similar. We also found the human rLN-8 to behave identically in cell adhesion assays compared to a human/mouse hybrid variant of rLN-8. PMID:12392759

  4. Complexes of V(3) with alpha-, beta- and gamma-picolines in alcohol solutions

    The systems of V(3) with alpha, beta and gamma-picolines in ethyl alcohol solutions were investigated by spectroscopic, conductometric and magnetic methods. VCl3 reacts with picolines in low concentrations of V(3) to produce 1:1 electrolytic, monomeric red-violet complexes of the type [VL4Cl2]+ (L=beta and gamma-pic.) and the brown complex of the type [V(alpha- pic)2Cl]-. Stability constants of the monomeric complexes were determined spectrophotometrically. At higher concentrations of V(3) the dimeric, 1:1 electrolytic, deep-violet complexes of the type [L3Cl2V-Cl-VCl2L3]+ (L=beta and gamma-pic.) are formed most probably. The V(3) complex with alpha-picoline is rather a monomer. (author)

  5. alpha 11beta 1 integrin recognizes the GFOGER sequence in interstitial collagens.

    Zhang, Wan-Ming; Kapyla, Jarmo; Puranen, J Santeri; Knight, C Graham; Tiger, Carl-Fredrik; Pentikainen, Olli T; Johnson, Mark S; Farndale, Richard W; Heino, Jyrki; Gullberg, Donald


    The integrins alpha(1)beta(1), alpha(2)beta(1), alpha(10)beta(1), and alpha(11)beta(1) are referred to as a collagen receptor subgroup of the integrin family. Recently, both alpha(1)beta(1) and alpha(2)beta(1) integrins have been shown to recognize triple-helical GFOGER (where single letter amino acid nomenclature is used, O = hydroxyproline) or GFOGER-like motifs found in collagens, despite their distinct binding specificity for various collagen subtypes. In the present study we have investigated the mechanism whereby the latest member in the integrin family, alpha(11)beta(1), recognizes collagens using C2C12 cells transfected with alpha(11) cDNA and the bacterially expressed recombinant alpha(11) I domain. The ligand binding properties of alpha(11)beta(1) were compared with those of alpha(2)beta(1). Mg(2+)-dependent alpha(11)beta(1) binding to type I collagen required micromolar Ca(2+) but was inhibited by 1 mm Ca(2+), whereas alpha(2)beta(1)-mediated binding was refractory to millimolar concentrations of Ca(2+). The bacterially expressed recombinant alpha(11) I domain preference for fibrillar collagens over collagens IV and VI was the same as the alpha(2) I domain. Despite the difference in Ca(2+) sensitivity, alpha(11)beta(1)-expressing cells and the alpha(11) I domain bound to helical GFOGER sequences in a manner similar to alpha(2)beta(1)-expressing cells and the alpha(2) I domain. Modeling of the alpha I domain-collagen peptide complexes could partially explain the observed preference of different I domains for certain GFOGER sequence variations. In summary, our data indicate that the GFOGER sequence in fibrillar collagens is a common recognition motif used by alpha(1)beta(1), alpha(2)beta(1), and also alpha(11)beta(1) integrins. Although alpha(10) and alpha(11) chains show the highest sequence identity, alpha(2) and alpha(11) are more similar with regard to collagen specificity. Future studies will reveal whether alpha(2)beta(1) and alpha(11)beta(1

  6. HPLC Analysis of [Alpha]- and [Beta]-Acids in Hops

    Danenhower, Travis M.; Force, Leyna J.; Petersen, Kenneth J.; Betts, Thomas A.; Baker, Gary A.


    Hops have been used for centuries to impart aroma and bitterness to beer. The cones of the female hop plant contain both essential oils, which include many of the fragrant components of hops, and a collection of compounds known as [alpha]- and [beta]-acids that are the precursors to bittering agents. In order for brewers to predict the ultimate…

  7. EEG Alpha and Beta Activity in Normal and Deaf Subjects.

    Waldron, Manjula; And Others

    Electroencephalogram and task performance data were collected from three groups of young adult males: profoundly deaf Ss who signed from an early age, profoundly deaf Ss who only used oral (speech and speedreading) methods of communication, and normal hearing Ss. Alpha and Beta brain wave patterns over the Wernicke's area were compared across…

  8. The alpha3 laminin subunit, alpha6beta4 and alpha3beta1 integrin coordinately regulate wound healing in cultured epithelial cells and in the skin

    Goldfinger, L E; Hopkinson, S B; deHart, G W;


    function-inhibiting antibodies, we provide evidence that LN5 and its two integrin receptors (alpha6beta4 and alpha3beta1) appear necessary for wound healing to occur in MCF-10A cell culture wounds. We propose a model for healing of wounded epithelial tissues based on these results....... epithelial cells. We have prepared a monoclonal antibody (12C4) whose epitope is located toward the carboxy terminus of the globular domain of the alpha3 laminin subunit. This epitope is lost from the alpha3 subunit as a consequence of proteolytic processing. Antibody 12C4 stains throughout the matrix of...... cover the wound site. A similar phenomenon is observed in human skin wounds, since we also detect expression of the unprocessed alpha3 laminin subunit at the leading tip of the sheet of epidermal cells that epithelializes skin wounds in vivo. In addition, using alpha3 laminin subunit and integrin...

  9. Impairment of physical performance after treatment with beta blockers and alpha blockers.

    Bengtsson, C.


    An investigation was made into the effect of various types of beta blockers, an alpha blocker, a combined alpha and beta blocker, and a diuretic on physical performance in a normotensive man. Beta blockers, the alpha blocker, and the combined alpha and beta blocker significantly (p less than 0.001) reduced physical performance. Further studies are needed to confirm these findings in a larger series of subjects.

  10. Evaluation and comparison of alpha- and beta-amanitin toxicity on MCF-7 cell line

    Kaya, Ertuğrul; BAYRAM, Recep; YAYKAŞLI, Kürşat Oğuz; YILMAZ, İsmail; BAYRAM, Sait


    Alpha- and beta-amanitins are the main toxins of the poisonous Amanita phalloides mushroom. Although there are many studies available concerning alpha-amanitin, there are limited data about beta-amanitin in the literature. Therefore, this study is aimed at comparing the toxic effects of alpha- and beta-amanitin on the MCF-7 cell line. Materials and methods: The alpha- and beta-amanitins used for this research were purified from Amanita phalloides by preparative high-performance liquid chrom...

  11. Expression and functional importance of collagen-binding integrins, alpha 1 beta 1 and alpha 2 beta 1, on virus-activated T cells

    Andreasen, Susanne Ø; Thomsen, Allan R; Koteliansky, Victor E; Novobrantseva, Tatiana I; Sprague, Andrew G; de Fougerolles, Antonin R; Christensen, Jan P


    Adhesive interactions are crucial to cell migration into inflammatory sites. Using murine lymphocytic choriomeningitis virus as an Ag model system, we have investigated expression and function of collagen-binding integrins, alpha(1)beta(1) and alpha(2)beta(1), on activated and memory T cells. Using...... this system and MHC tetramers to define Ag-specific T cells, we demonstrate that contrary to being VLAs, expression of alpha(1)beta(1) and alpha(2)beta(1) can be rapidly induced on acutely activated T cells, that expression of alpha(1)beta(1) remains elevated on memory T cells, and that expression of...... alpha(1)beta(1) parallels that of viral-specific effector CD8(+) T cells (defined by tetramer and IFN-gamma staining). In an adoptive transfer model, mAb-mediated blockade of these integrins on activated effector and memory T cells inhibited Ag-specific delayed-type hypersensitivity responses; similar...

  12. Collective search by mobile robots using alpha-beta coordination

    Goldsmith, S.Y.; Robinett, R. III


    One important application of mobile robots is searching a geographical region to locate the origin of a specific sensible phenomenon. Mapping mine fields, extraterrestrial and undersea exploration, the location of chemical and biological weapons, and the location of explosive devices are just a few potential applications. Teams of robotic bloodhounds have a simple common goal; to converge on the location of the source phenomenon, confirm its intensity, and to remain aggregated around it until directed to take some other action. In cases where human intervention through teleoperation is not possible, the robot team must be deployed in a territory without supervision, requiring an autonomous decentralized coordination strategy. This paper presents the alpha beta coordination strategy, a family of collective search algorithms that are based on dynamic partitioning of the robotic team into two complementary social roles according to a sensor based status measure. Robots in the alpha role are risk takers, motivated to improve their status by exploring new regions of the search space. Robots in the beta role are motivated to improve but are conservative, and tend to remain aggregated and stationary until the alpha robots have identified better regions of the search space. Roles are determined dynamically by each member of the team based on the status of the individual robot relative to the current state of the collective. Partitioning the robot team into alpha and beta roles results in a balance between exploration and exploitation, and can yield collective energy savings and improved resistance to sensor noise and defectors. Alpha robots waste energy exploring new territory, and are more sensitive to the effects of ambient noise and to defectors reporting inflated status. Beta robots conserve energy by moving in a direct path to regions of confirmed high status.

  13. : beta-carotene, alpha-linolenate and carcinogenesis.

    Maillard, Virginie; Hoinard, Claude; Arab, Khelifa; Jourdan, Marie-Lise; Bougnoux, Philippe; Chajès, Véronique


    To investigate whether dietary alpha-linolenic acid (ALA) content alters the effect of beta-carotene on mammary carcinogenesis, we conducted a chemically induced mammary tumorigenesis experiment in rats randomly assigned to four nutritional groups (15 rats per group) varying in beta-carotene supplementation and ALA content. Two oil formula-enriched diets (15 %) were used: one with 6 g ALA/kg diet in an essential fatty acids (EFA) ratio of linoleic acid:ALA of 5:1 w/w (EFA 5 diet), the other w...

  14. ADAM12 and alpha9beta1 integrin are instrumental in human myogenic cell differentiation

    Lafuste, Peggy; Sonnet, Corinne; Chazaud, Bénédicte; Dreyfus, Patrick A; Gherardi, Romain K; Wewer, Ulla M; Authier, François-Jérôme


    of alpha9 parallels that of ADAM12 and culminates at time of fusion. alpha9 and ADAM12 coimmunoprecipitate and participate to mpc adhesion. Inhibition of ADAM12/alpha9beta1 integrin interplay, by either ADAM12 antisense oligonucleotides or blocking antibody to alpha9beta1, inhibited overall mpc...

  15. Recombinant laminin-8 (alpha(4)beta(1)gamma(1)). Production, purification,and interactions with integrins.

    Kortesmaa, J; Yurchenco, P; Tryggvason, K


    Laminins are a large family of heterotrimeric extracellular matrix glycoproteins that, in addition to having structural roles, take part in the regulation of processes such as cell migration, differentiation, and proliferation. The laminin alpha(4) chain is widely distributed both in adults and during development in tissues such as cardiac, skeletal and smooth muscle fibers, vascular endothelia, lungs, and in peripheral nerves. It can associate with laminin beta(1)/gamma(1) chains to form laminin-8 and with the beta(2)/gamma(1) chains to form laminin-9. Functional studies on these laminins have been hampered by poor availability of the protein in pure and soluble forms. To facilitate studies on laminin-8, recombinant laminin-8 was produced in a mammalian expression system, purified and shown to form native Y-shaped molecules in rotary shadowing electron microscopy. Integrins mediating cell adhesion to laminin-8 were identified using function-blocking mAbs. The integrin specificities were found to differ somewhat from that of laminin-1. Integrin alpha(6)beta(1) was found to be a major mediator of adhesion of HT-1080 and cultured capillary endothelial cells to laminin-8. Considering the expression patterns of laminin-8 and integrin alpha(6)beta(1) it is likely that the former is a ligand for the latter in vivo as well. PMID:10809728

  16. Preconcentration techniques of alpha and beta emitters in environmental samples

    As is well known it is often necessary to determine very low activities of alpha and beta emitters in environmental and industrial samples for radiation protection purposes. Therefore, due to self absorption problems, the radioisotopes to be determined must be concentrated and isolated before any counting procedure. The radiochemical separation techniques shortly described are the following: the distillation of HTO for the determination of tritium in aqueous solution by liquid scintillation counting; the coprecipitation of Ra-226 and Y-90 before the low background alpha and beta counting. A particular emphasis is devoted to Column Reversed Phase Partition Chromatography (Extraction Chromatography) which has been successfully used in the last years for radioecological and radio-toxicological purposes

  17. Haemopoietic effects of 7 alpha, 17 beta dimethyltestosterone

    Some haematic parameters were investigated in female COBS mice treated with 7 alpha, 17 beta Dimethyltestosterone (DMT). The drug causes an increase of circulating platelets in normal mice. Bone marrow graft from DMT-treated donors facilitates in irradiated mice repopulation of white blood cells and platelets but lowers % survival. These data are interpreted on the basis of a 'commitment' and a loss of self-maintenance induced by DMT on CFUs compartment. (author)

  18. Gross alpha/beta measurements in water samples using liquid scintillation counter

    Liquid scintillation techniques provide the detection and quantification of alpha and beta emitters in aqueous sample. Liquid Scintillation Counter (LSC) techniques using Pulse Decay Analysis (PDA) allow counting of alpha and beta radiation in the same sample simultaneously. PDA uses special pulse decay time discrimination electronics to differentiate alpha pulses from beta pulses in a liquid scintillator. In this experiment, Packard Tricarb 2770 TR-SL LSC has been used. Ultima Gold LLT produced by Packard Instrument Company was used as the liquid scintillator. The optimum counting parameters and Pulse Decay Discriminator (PDD) settings were provided for the best alpha and beta separation. PDD was verified by counting a pure alpha ''2''4''1Am and a pure beta ''3''6Cl. Spill of beta in alpha and alpha in beta was found around 0.1% at the optimum discriminator setting of 139. The counting efficiencies were 100% and 97% for alpha and beta counting respectively. Water samples were pre-concentrated to achieve the Turkish maximum permissible levels of 0.037 BqL''-''1 for gross alpha radioactivity and 0.37 BqL''-''1 for gross beta radioactivity in drinking water. After counting, the alpha and beta spill corrections were made and the gross alpha and beta radioactivities were calculated. LSC method results were compared with the gas flow proportional counters

  19. Function of the integrin alpha 6 beta 1 in metastatic breast carcinoma cells assessed by expression of a dominant-negative receptor

    Shaw, L M; Chao, C; Wewer, U M;


    : alpha 2 beta 1, alpha 3 beta 1, and alpha 6 beta 1, but uses only alpha 6 beta 1 to mediate adhesion and migration on laminin matrices. To investigate the contribution of alpha 6 beta 1 to the aggressive behavior of these cells, we developed a dominant-negative strategy for knocking out alpha 6 beta 1...

  20. Inversion in the lactose region of Escherichia coli K-12: inversion termini map within IS3 elements alpha 3 beta 3 and beta 5 alpha 5.

    Savić, D J; Romac, S P; Ehrlich, S D


    In this work, the previously described inversion in the lactose region of the Escherichia coli K-12 chromosome (D. J. Savić, J. Bacteriol. 140:311-319, 1979) is analyzed in greater detail. The results presented indicate that the inversion most likely occurred by a homologous recombination between alpha 3 beta 3 and beta 5 alpha 5 IS3 elements.

  1. Prolyl hydroxylation of collagen type I is required for efficient binding to integrin alpha 1 beta 1 and platelet glycoprotein VI but not to alpha 2 beta 1.

    Perret, Stéephanie; Eble, Johannes A; Siljander, Pia R-M; Merle, Christine; Farndale, Richard W; Theisen, Manfred; Ruggiero, Florence


    Collagen is a potent adhesive substrate for cells, an event essentially mediated by the integrins alpha 1 beta 1 and alpha 2 beta 1. Collagen fibrils also bind to the integrin alpha 2 beta 1 and the platelet receptor glycoprotein VI to activate and aggregate platelets. The distinct triple helical recognition motifs for these receptors, GXOGER and (GPO)n, respectively, all contain hydroxyproline. Using unhydroxylated collagen I produced in transgenic plants, we investigated the role of hydroxyproline in the receptor-binding properties of collagen. We show that alpha 2 beta 1 but not alpha 1 beta 1 mediates cell adhesion to unhydroxylated collagen. Soluble recombinant alpha 1 beta 1 binding to unhydroxylated collagen is considerably reduced compared with bovine collagens, but binding can be restored by prolyl hydroxylation of recombinant collagen. We also show that platelets use alpha 2 beta 1 to adhere to the unhydroxylated recombinant molecules, but the adhesion is weaker than on fully hydroxylated collagen, and the unhydroxylated collagen fibrils fail to aggregate platelets. Prolyl hydroxylation is thus required for binding of collagen to platelet glycoprotein VI and to cells by alpha 1 beta 1. These observations give new insights into the molecular basis of collagen-receptor interactions and offer new selective applications for the recombinant unhydroxylated collagen I. PMID:12771137

  2. Mouse egg integrin alpha 6 beta 1 functions as a sperm receptor.

    Almeida, E A; Huovila, A P; Sutherland, A E; Stephens, L E; Calarco, P G; Shaw, L M; Mercurio, A M; Sonnenberg, A; Primakoff, P; Myles, D G; White, J M


    Binding between sperm and egg plasma membranes is an essential step in fertilization. Whereas fertilin, a mammalian sperm surface protein, is involved in this crucial interaction, sperm receptors on the egg plasma membrane have not been identified. Because fertilin contains a predicted integrin ligand domain, we investigated the expression and function of integrin subunits in unfertilized mouse eggs. Polymerase chain reactions detected mRNAs for alpha 5, alpha 6, alpha v, beta 1, beta 3, and beta 5. Immunofluorescence revealed alpha 6 beta 1 and alpha v beta 3 on the plasma membrane. GoH3, a function-blocking anti-alpha 6 monoclonal antibody, abolished sperm binding, but a nonfunction-blocking anti-alpha 6 monoclonal antibody, a function-blocking anti-alpha v beta 3 polyclonal antibody, and an RGD peptide had no effect. Somatic cells bound sperm avidly, but only if they expressed alpha 6 beta 1. A peptide analog of the fertilin integrin ligand domain inhibited sperm binding to eggs and alpha 6 beta 1+ cells and diminished GoH3 staining of eggs. Our results indicate a novel role for the integrin alpha 6 beta 1 as a cell-cell adhesion receptor that mediates sperm-egg binding. PMID:7600577

  3. Synthesis and reactivity of {alpha}-phenylseleno-{beta}-substituted styrenes: preparation of (Z)-allyl alcohols, (E)-{alpha}-phenyl-{alpha},{beta}-unsaturated aldehydes and {alpha}-aryl acetophenones

    Lenardao, Eder J.; Jacob, Raquel G.; Silva, Thiago B. da [Universidade Federal de Pelotas, RS (Brazil). Dept. de Quimica Analitica e Inorganica]. E-mail:; Cella, Rodrigo [Santa Maria Univ., RS (Brazil). Dept. de Quimica; Perin, Gelson [Universidade Federal de Pelotas, RS (Brazil). Dept. de Quimica Organica


    A new and efficient method was developed to prepare {alpha}-phenylseleno-{beta}-substituted styrenes by reaction of diethyl {alpha}-phenylseleno benzylphosphonate with NaH and aldehydes. Selenium-lithium exchange by reaction with n-BuLi yielded the vinyl lithium species, which were captured with several electrophiles, like aldehydes and DMF, affording exclusively (Z)-allyl alcohols, and (E)-{alpha}-phenyl-{alpha}-{beta}-unsaturated aldehydes, respectively in good yields. The hydrolysis of the vinyl selenides in presence of TiCl{sub 4} allowed the corresponding {alpha}-aryl acetophenones. (author)

  4. Theta, alpha and beta burst transcranial magnetic stimulation: brain modulation in tinnitus

    Dirk De Ridder, Elsa van der Loo, Karolien Van der Kelen, Tomas Menovsky, Paul van de Heyning, Aage Moller


    Introduction: Some forms of tinnitus are considered to be auditory phantom phenomena related to reorganization and hyperactivity of the auditory central nervous system. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive tool capable of modulating human brain activity, using single pulse or burst stimuli. Burst rTMS has only been performed in the theta range, and has not been used clinically. The authors analyze whether burst TMS at theta (5 Hz), alpha (10 Hz) and beta (20 H...

  5. Ontogeny of alpha- and beta-adrenergic anorexia in rats.

    Lora-Vilchis, M C; Chambert, G; Rodriguez-Zendejas, A M; Soto-Mora, L M; Russek, M; Epstein, A N


    The anorectic action of alpha- (phenylephrine) and beta- (isoproterenol) adrenergic agonists was studied in mildly deprived neonatal, weanling, prepubescent, and adult rats. Intraperitoneal phenylephrine produced a reduction of food intake at all ages but with reduced potency and with a maximum of 50% in neonates. Contrary to intramuscular epinephrine that has no effect on feeding at any age, intramuscular phenylephrine was as effective as intraperitoneal in neonates, probably because it is not as rapidly destroyed in tissues as epinephrine. However, in weanlings and adults intramuscular phenylephrine was much less anorectic than intraperitoneal, suggesting that this effect is exerted via the liver. Isoproterenol did not reduce milk intake at any age before adulthood. Lactate had no effect on milk intake before the age of 40 days. Thus catecholamine anorexia is a purely alpha-adrenergic effect in young rats and appears before the metabolic effect of lactate. beta-Adrenergic anorexia, on the other hand, can be obtained only after puberty, suggesting that the mechanism mediating it matures after the preparatory action of the sexual hormones. PMID:2849323

  6. Regulatory sequences within DQ. cap alpha. and DQ. beta

    Sullivan, K.; Peterlin, B.M.


    The Class II Histocompatibility Antigen DQ is characterized by tissue specific expression, relatively late appearance in development and modulation of expression in response to gamma interferon, phorbol 12-myristate 13-acetate (PMA), and prostaglandins of the E series. They have utilized the sensitive reporter function of chloramphenicol acetyl transferase (CAT) in transient expression assays to screen for the presence of regulatory regions within the DQ..cap alpha.. and DQ..beta.. genes. Two regions have been identified which stimulate CAT transcription in transfected cells. One region includes the first intron of DQ..beta.. and the other region brackets the first exon of DQ/sup 2/. These regions are both tissue specific in their stimulation of CAT transcription i.e., both regions stimulate transcription more effectively in a DQ expressing B cell line (BJAB) than in a DQ negative T cell line (Jurkat). Additionally, the CAT plasmids containing the first intron of DQ..beta.. appear to be gamma interferon responsive. Transfection of these plasmids into BJAB followed by treatment of the cells with gamma interferon for 24 hours results in a doubling of the CAT transcription. This increase is analogous to the endogenous DQ response to gamma interferon. These two regions undoubtedly contribute to the complex regulation of DQ expression.

  7. Quartz luminescence response to a mixed alpha-beta field: Investigations on Romanian loess

    Constantin, Daniela; Jain, Mayank; Murray, Andrew S.; Buylaert, Jan-Pieter; Timar-Gabor, Alida


    beta radiation follow the same recombination path. We also show that a mixed alpha-beta dose response reproduces the beta dose response only up to about 800Gy. Assuming an a-value of 0.04 we have shown that laboratory alpha and beta dose response curves overlap up to effective alpha doses of ~50Gy....... Based on these results, we conclude that exposure of fine grains to alpha radiation during burial and transport cycles prior to deposition, as well exposure to the mixed radiation field experienced during burial are not responsible for the age discrepancies previously reported on fine and coarse grained......-OSL laboratory dose response curves do not reflect the growth of the OSL signal in nature. A main difference in coarse- and fine-grained quartz dating lies in the alpha irradiation history, but the effect of mixed alpha-beta fields has so far received little attention. In the present study we investigate whether...

  8. Mechanism of concerted inhibition of alpha2beta2-type hetero-oligomeric aspartate kinase from Corynebacterium glutamicum.

    Yoshida, Ayako; Tomita, Takeo; Kuzuyama, Tomohisa; Nishiyama, Makoto


    Aspartate kinase (AK) is the first and committed enzyme of the biosynthetic pathway producing aspartate family amino acids, lysine, threonine, and methionine. AK from Corynebacterium glutamicum (CgAK), a bacterium used for industrial fermentation of amino acids, including glutamate and lysine, is inhibited by lysine and threonine in a concerted manner. To elucidate the mechanism of this unique regulation in CgAK, we determined the crystal structures in several forms: an inhibitory form complexed with both lysine and threonine, an active form complexed with only threonine, and a feedback inhibition-resistant mutant (S301F) complexed with both lysine and threonine. CgAK has a characteristic alpha(2)beta(2)-type heterotetrameric structure made up of two alpha subunits and two beta subunits. Comparison of the crystal structures between inhibitory and active forms revealed that binding inhibitors causes a conformational change to a closed inhibitory form, and the interaction between the catalytic domain in the alpha subunit and beta subunit (regulatory subunit) is a key event for stabilizing the inhibitory form. This study shows not only the first crystal structures of alpha(2)beta(2)-type AK but also the mechanism of concerted inhibition in CgAK. PMID:20573952

  9. Pax4 Expression does not Transduce Pancreatic Alpha Cells to Beta Cells

    Ling Chen


    Full Text Available Background/Aims: The lack of available beta cells greatly limits the use of beta cell transplantation as a therapy for diabetes. Thus, generation of beta cells from other sources is substantially required. Pax4 has been shown to induce reprograming of alpha cells into beta cells during embryogenesis. Nevertheless, whether expression of Pax4 in adult alpha cells could trigger this alpha-to-beta cell reprogramming is unknown. Methods: Here we generated an adeno-associated virus carrying Pax4 and GFP under a CMV promoter (AAV-Pax4. We used AAV-Pax4 to transduce a mouse alpha cell line in vitro, and to transduce primary alpha cells in diabetic mice. Reprogramming was examined by double immunostaining and by changes in beta cell number. The effects on blood glucose were evaluated by fasting blood glucose and glucose response. Results: In vitro, Pax4 overexpression neither induced insulin expression, nor suppressed glucagon expression in alpha cells. In vivo, Pax4 overexpression failed to increase beta cell number, and did not alter hyperglycemia and glucose response in diabetic mice. Conclusion: Pax4 expression is not sufficient to transduce pancreatic alpha cells into beta cells. Overexpression of Pax4 in alpha cells may not increase functional beta cell number in diabetic patients.

  10. Nicotinic {alpha}4{beta}2 receptor imaging agents

    Pichika, Rama [Brain Imaging Center, Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697-3960 (United States); Easwaramoorthy, Balasubramaniam [Brain Imaging Center, Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697-3960 (United States); Collins, Daphne [Brain Imaging Center, Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697-3960 (United States); Christian, Bradley T. [Department of Nuclear Medicine, Kettering Medical Center, Dayton, OH 45429 (United States); Shi, Bingzhi [Department of Nuclear Medicine, Kettering Medical Center, Dayton, OH 45429 (United States); Narayanan, Tanjore K. [Department of Nuclear Medicine, Kettering Medical Center, Dayton, OH 45429 (United States); Potkin, Steven G. [Brain Imaging Center, Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697-3960 (United States); Mukherjee, Jogeshwar [Brain Imaging Center, Department of Psychiatry and Human Behavior, University of California, Irvine, CA 92697-3960 (United States)]. E-mail:


    The {alpha}4{beta}2 nicotinic acetylcholine receptor (nAChR) has been implicated in various neurodegenerative diseases. Optimal positron emission tomography (PET) imaging agents are therefore highly desired for this receptor. We report here the development and initial evaluation of 2-fluoro-3-[2-((S)-3-pyrrolinyl)methoxy]pyridine (nifene). In vitro binding affinity of nifene in rat brain homogenate using {sup 3}H-cytisine exhibited a K {sub i}=0.50 nM for the {alpha}4{beta}2 sites. The radiosynthesis of 2-{sup 18}F-fluoro-3-[2-((S)-3-pyrrolinyl)methoxy]pyridine ({sup 18}F-nifene) was accomplished in 2.5 h with an overall radiochemical yield of 40-50%, decay corrected. The specific activity was estimated to be approx. 37-185 GBq/{mu}mol. In vitro autoradiography in rat brain slices indicated selective binding of {sup 18}F-nifene to anteroventral thalamic (AVT) nucleus, thalamus, subiculum, striata, cortex and other regions consistent with {alpha}4{beta}2 receptor distribution. Rat cerebellum showed some binding, whereas regions in the hippocampus had the lowest binding. The highest ratio of >13 between AVT and cerebellum was measured for {sup 18}F-nifene in rat brain slices. The specific binding was reduced (>95%) by 300 {mu}M nicotine in these brain regions. Positron emission tomography imaging study of {sup 18}F-nifene (130 MBq) in anesthetized rhesus monkey was carried out using an ECAT EXACT HR+ scanner. PET study showed selective maximal uptake in the regions of the anterior medial thalamus, ventro-lateral thalamus, lateral geniculate, cingulate gyrus, temporal cortex including the subiculum. The cerebellum in the monkeys showed lower binding than the other regions. Thalamus-to-cerebellum ratio peaked at 30-35 min postinjection to a value of 2.2 and subsequently reduced. The faster binding profile of {sup 18}F-nifene indicates promise as a PET imaging agent and thus needs further evaluation.

  11. Characteristics of continuous cooling transformation in [alpha]+[beta] titanium alloys. [alpha]+[beta] gata gokin no hentai soshikii keisei model to netsukan ensei teika gensho no kaimei

    Fujii, H. (Nippon Steel Corp., Tokyo (Japan))


    When [alpha]+[beta] titanium alloys are subject to a [beta] process, i.e. the alloys are heated to the [beta] region; the temperature is maintained; and then the alloy are cooled, they present several transformation microstructures depending on cooling speeds. In this study, the cooling speed from the [beta] region was varied to examine the effect of cooling speed on the formation of microstructures. This effect is now undergoing continued examination. In this study, using Ti-6Al-4V and Ti-6Al-6V-2Sn alloys, the diffusion transformation was especially examined and the following results were obtained: the diffusion transformation develops by generation of side-plate [alpha]-phase instead of growth of grain boundary [alpha]-phase. For such the structural behavior, based on the assumption that vanadium which concentrates near the grain boundary [alpha]-phase in early stages of the transformation plays an important role, a model of formation mechanism of Widmanstatten microstructure is developed. The ductility loss of the Widmanstatten microstructure in the specified [alpha]+[beta] temperature range can be explained by the model which presents the solution that the loss is a result of generation of the special microstructure region containing the soft [beta]-phase at higher percentage along the grain boundary [alpha]-phase. 21 refs., 10 figs., 1 tab.

  12. Selective cell adhesion inhibitors: Barbituric acid based alpha4beta7--MAdCAM inhibitors.

    Harriman, Geraldine C; Brewer, Matthias; Bennett, Robert; Kuhn, Cyrille; Bazin, Marc; Larosa, Greg; Skerker, Paul; Cochran, Nancy; Gallant, Debra; Baxter, Deborah; Picarella, Dominic; Jaffee, Bruce; Luly, Jay R; Briskin, Michael J


    A novel series of barbituric acid derivatives were identified as selective inhibitors of alpha4beta7 MAdCAM (mucosal addressin cell adhesion molecule-1) interactions via a high throughput screening exercise. These inhibitors were optimized to submicromolar potencies in whole cell adhesion assays, retaining their selectivity over alpha4beta1 VCAM. PMID:18331794

  13. Beta delayed alpha emission from the neutron deficient rare earth isotopes 152Tm and 150Ho

    The study of beta-delayed proton emission is a well known method to aid the determination of the beta strength distribution in nuclei far from the stability line. At the neutron deficient side of the nuclear chart the process of proton or alpha emission from excited states is energetically allowed when one goes far enough from stability. However, beta-delayed alphas have seldom been measured for nuclei heavier than A = 20. Here we present a study of the beta-delayed alpha-particle emission from 152Tm and 150Ho and their importance in the full B(GT) distribution.

  14. Alpha-beta monitoring system based on pair of simultaneous Multi-Wire Proportional Counters

    Wengrowicz, U.; Amidan, D.; Orion, I.


    A new approach for a simultaneous alpha-beta Multi-wire Proportional Counter (MWPC) is presented. The popular approach for alpha-beta monitoring systems consists of a large area MWPC using noble gas flow such as Argon Methane. This method of measurement is effective but requires large-scale and expensive maintenance due to the needs of gas flow control and periodic replacements. In this work, a pair of simultaneous MWPCs for alpha-beta measuring is presented. The developed detector consists of a sealed gas MWPC sensor for beta particles, behind a free air alpha sensor. This approach allows effective simultaneous detection and discrimination of both alpha and beta radiation without the maintenance cost noble gas flow required for unsealed detectors.

  15. Liquid scintillation alpha-beta-radiometer TIM-100

    The basic purpose is direct analysis of strontium 90 specific activity in water samples without preliminary concentration. Radiometer can be applied also to the direct analysis of total specific activity of alpha-radiating nuclides in drinking water and for determination of radon specific activity in water. The measurements of specific beta-activity of drinking water don't demand of preliminary preparation of samples: it is not necessary to perform concentration or radiochemical separation of strontium 90 from water samples. Measurement time along with preparation of the device for work is no more than 2 hours. Volume of test of water is 2,5 litres. Minimal detected activity (MDA) for strontium 90 is of 0,37 Bq/l at 90 minutes measurement time, relative error is 50%, confidence level is 0,95. It is supposed that in tests of water strontium 90 is in radioactive equilibrium with their daughter isotope yttrium 90. In samples of water the presence of others isotopes interfering strontium-90 is possible, for example, cesium 137 and potassium 40. For strontium 90 MDA of 0,37 Bq/l is achieved in cases when values of specific activities of specified isotopes satisfy to the following conditions: cesium 137 < 20 Bq/l; potassium 40 < 1 Bq/l. Along with determination of strontium 90 concentration in water samples it is possible to measure the total specific activity of alpha-radiating isotopes: plutonium 239, americium 241 etc. MDA of alpha isotopes is 1,85 Bq/l (measurement time is 90 min., relative error is 50 %, confidence level is 0,95)

  16. Biosynthesis of Tcr-alpha, beta and Tcr-gamma, delta/CD3 complexes

    Bauguil-Caspar, S; Arnaud, J; Kuhlmann, J; Geisler, C; Rubin, B

    Jurkat J76 clone, LYON L12.37 clone and L12.37 cells transfected with J76-alpha cDNA or J76 Tcr-alpha mutated cDNA (J79) were analysed for membrane expression of Tcr/CD3 complex using WT31 mAb (Tcr-alpha, beta) or Tcr-delta 1 mAb (Tcr-gamma, delta): LYON cells express V beta 9 bearing Tcr......-beta chains. J76 Tcr-alpha cDNA transfected LYON cells have intracellular Tcr-gamma, delta chains and J79 Tcr-alpha cDNA transfected LYON cells have intracellular Tcr-alpha (M), beta chains....

  17. Application of semiempirical expressions to the alpha and beta radiometry of environmental depositions samples

    Were applied two semiempirical equations exponential beta absorption and Bragg-Kleeman approximation complementary to experimental corrections for beta backscattering and auto absorption of beta and alpha radiations in measurements of environmental depositions samples In the first case was verified the validity of mentioned corrections with an application boundary to mass greater than 300 Pb-210 (0.015 mg/cm2) In the second case, the Bragg-Kleeman approximation combined with the experimental beta corrections, bring a judgment to determine the fundamental alpha and beta emisors samples which results the Pb-210 group

  18. The Schizosaccharomyces pombe casein kinase II alpha and beta subunits: evolutionary conservation and positive role of the beta subunit.

    Roussou, I; Draetta, G


    Casein kinase II is a key regulatory enzyme involved in many cellular processes, including the control of growth and cell division. We report the molecular cloning and sequencing of cDNAs encoding the alpha and the beta subunits of casein kinase II of Schizosaccharomyces pombe. The deduced amino acid sequence of Cka1, the alpha catalytic subunit, shows high sequence similarity to alpha subunits identified in other species. The amino acid sequence of Ckb1, the S. pombe beta subunit, is 57% ide...

  19. The interaction of CK2alpha and CK2beta, the subunits of protein kinase CK2, requires CK2beta in a preformed conformation and is enthalpically driven

    Raaf, Jennifer; Brunstein, Elena; Issinger, Olaf-Georg; Niefind, Karsten


    The protein kinase CK2 (former name: "casein kinase 2") predominantly occurs as a heterotetrameric holoenzyme composed of two catalytic chains (CK2alpha) and two noncatalytic subunits (CK2beta). The CK2beta subunits form a stable dimer to which the CK2alpha monomers are attached independently. In...... contrast to the cyclins in the case of the cyclin-dependent kinases CK2beta is no on-switch of CK2alpha; rather the formation of the CK2 holoenzyme is accompanied with an overall change of the enzyme's profile including a modulation of the substrate specificity, an increase of the thermostability, and an...... allocation of docking sites for membranes and other proteins. In this study we used C-terminal deletion variants of human CK2alpha and CK2beta that were enzymologically fully competent and in particular able to form a heterotetrameric holoenzyme. With differential scanning calorimetry (DSC) we confirmed the...

  20. Cyclic deformation behavior of an {alpha}/{beta} titanium alloy. 2: Internal stresses and micromechanic modelling

    Feaugas, X.; Clavel, M. [Univ. de Technologie de Compiegne (France); Pilvin, P. [Univ. Paris VI, Evry (France)]|[Ecole des Mines de Paris, Evry (France). Centre des Materiaux


    A micromechanic model was used to study the influence of the different microstructure heterogeneity levels of an {alpha}/{beta} titanium alloy during monotonic and cyclic loadings. In the micromechanic model two levels of heterogeneity were considered: the cell and the two phases ({alpha} and {beta}). The cell is defined as an {alpha} (h.c.p.) crystal surrounded by {beta}-phase (b.c.c.). A modified Kroener`s rule is used to describe the stress localization. This rule takes into account the elasto-plastic accommodation between cells and between phases. The main results are the following: the rate of reduction of the {alpha}/{beta} incompatibilities is greater than that associated with inter-cells and the cyclic softening depends not only on the reduction of the transgranular incompatibilities ({alpha}-phase), but also on inter-cell internal stress redistribution.

  1. On Schr\\"odinger equation with potential U = - {\\alpha}r^{-1} + {\\beta}r + kr^{2} and the bi-confluent Heun functions theory

    Ovsiyuk, E; Veko, O


    It is shown that Schr\\"odinger equation with combination of three potentials U = - {\\alpha} r^{-1} + {\\beta} r + kr^{2}, Coulomb, linear and harmonic, the potential often used to describe quarkonium, is reduced to a bi-confluent Heun differential equation. The method to construct its solutions in the form of polynomials is developed, however with additional constraints in four parameters of the model, {\\alpha}, {\\beta}, k, l. The energy spectrum looks as a modified combination of oscillator and Coulomb parts.

  2. Blood platelets contain and secrete laminin-8 (alpha4beta1gamma1) and adhere to laminin-8 via alpha6beta1 integrin.

    Geberhiwot, T; Ingerpuu, S; Pedraza, C; Neira, M; Lehto, U; Virtanen, I; Kortesmaa, J; Tryggvason, K; Engvall, E; Patarroyo, M


    Laminins, a family of heterotrimeric proteins with cell adhesive/signaling properties, are characteristic components of basement membranes of vasculature and tissues. In the present study, permeabilized platelets were found to react with a monoclonal antibody to laminin gamma1 chain by immunofluorescence. In Western blot analysis of platelet lysates, several monoclonal antibodies to gamma1 and beta1 laminin chains recognized 220- to 230-kDa polypeptides, under reducing conditions, and a structure with much slower electrophoretic mobility under nonreducing conditions. Immunoaffinity purification on a laminin beta1 antibody-Sepharose column yielded polypeptides of 230, 220, 200, and 180 kDa from platelet lysates. In the purified material, mAbs to beta1 and gamma1 reacted with the two larger polypeptides, while affinity-purified rabbit antibodies to laminin alpha4 chain recognized the smallest polypeptide. Identity of the polypeptides was confirmed by microsequencing. One million platelets contained on average 1 ng of laminin (approximately 700 molecules per cell), of which 20-35% was secreted within minutes after stimulation with either thrombin or phorbol ester. Platelets adhered to plastic surfaces coated with the purified platelet laminin, and this process was largely inhibited by antibodies to beta1 and alpha6 integrin chains. We conclude that platelets contain and, following activation, secrete laminin-8 (alpha4beta1gamma1) and that the cells adhere to the protein by using alpha6beta1 integrin. PMID:10585296

  3. Alternative splicing produces transcripts coding for alpha and beta chains of a hetero-dimeric phosphagen kinase.

    Ellington, W Ross; Yamashita, Daisuke; Suzuki, Tomohiko


    Glycocyamine kinase (GK) catalyzes the reversible phosphorylation of glycocyamine (guanidinoacetate), a reaction central to cellular energy homeostasis in certain animals. GK is a member of the phosphagen kinase enzyme family and appears to have evolved from creatine kinase (CK) early in the evolution of multi-cellular animals. Prior work has shown that GK from the polychaete Neanthes (Nereis) diversicolor exits as a hetero-dimer in vivo and that the two polypeptide chains (termed alpha and beta) are coded for by unique transcripts. In the present study, we demonstrate that the GK from a congener Nereis virens is also hetero-dimeric and is coded for by alpha and beta transcripts, which are virtually identical to the corresponding forms in N. diversicolor. The GK gene from N. diversicolor was amplified by PCR. Sequencing of the PCR products showed that the alpha and beta chains are the result of alternative splicing of the GK primary mRNA transcript. These results also strongly suggest that this gene underwent an early tandem exon duplication event. Full-length cDNAs for N. virens GKalpha and GKbeta were individually ligated into expression vectors and the resulting constructs used to transform Escherichia coli expression hosts. Regardless of expression conditions, minimal GK activity was observed in both GKalpha and GKbeta constructs. Inclusion bodies for both were harvested, unfolded in urea and alpha chains, beta chains and mixtures of alpha and beta chains were refolded by sequential dialysis. Only modest amounts of GK activity were observed when alpha and beta were refolded individually. In contrast, when refolded the alpha and beta mixture yielded highly active hetero-dimers, as validated by size exclusion chromatography, electrophoresis and mass spectrometry, with a specific activity comparable to that of natural GK. The above evidence suggests that there is a preference for hetero-dimer formation in the GKs from these two polychaetes. The evolution of the

  4. C/EBP beta regulation of the tumor necrosis factor alpha gene.

    Pope, R. M.; Leutz, A; Ness, S A


    Activated macrophages contribute to chronic inflammation by the secretion of cytokines and proteinases. Tumor necrosis factor alpha (TNF alpha) is particularly important in this process because of its ability to regulate other inflammatory mediators in an autocrine and paracrine fashion. The mechanism(s) responsible for the cell type-specific regulation of TNF alpha is not known. We present data to show that the expression of TNF alpha is regulated by the transcription factor C/EBP beta (NF-I...

  5. The physiological and pharmacological role of presynaptic alpha- and beta-adrenoceptors in man.

    Brown, M. J.; Struthers, A D; Burrin, J M; Di Silvio, L.; Brown, D. C.


    Two studies were performed each in six normal volunteers in order to find evidence of either a physiological or pharmacological role of presynaptic alpha- and presynaptic beta-adrenoceptors in man. In Study 1 subjects received a 60 min infusion of guanfacine 3 mg (alpha 2-adrenoceptor agonist) preceded by either idazoxan (alpha 2-adrenoceptor antagonist) or vehicle. Guanfacine reduced plasma noradrenaline concentration by approximately 30% and this fall was not antagonised by the alpha 2-rece...

  6. Improved method for the complete separation of gross alpha and beta emitters in drinking water

    During this work, a modified methodology for the separation of gross alpha and beta activity from potable water is proposed. Laboratory spiked experiments show a recovery of gross radioactivity in the range of 98-99% with the proposed methodology. The detection limits using this methodology are 20mBq/l and 2mBq/l for gross beta and alpha respectively. These detection limits are two order of magnitude lower than the maximum acceptable concentration of gross alpha and gross beta activity i.e. less than 0.5/(0.1) Bq/L and 1 Bq/L, respectively. (author)

  7. Gross alpha and gross beta radioactivity in drinking water from Zacatecas and Guadalupe cities, Mexico

    The conditions to measure the gross alpha and gross beta radioactivity in water samples from Zacatecas and Guadalupe cities in the State of Zacatecas, Mexico were established. The gross alpha and beta radioactivity of water samples were measured using a liquid scintillation detector. The results show that the gross beta radioactivity in all cases is lower than the maximum contaminant level and the gros alpha radioactivity is higher in the samples collected from Guadalupe City and in the samples collected from the Southwest of Zacatecas City. (author)

  8. Calibrating instrument of plane sources of alpha and beta

    The instrument is standard instrument for measuring emissivity of plane sources of alpha and beta under 2π geometry in radionuclide metrologic technique. It is composed of box-type detector and truck-type NIM (made in China) to make up integral equipment. Its detector is composed of multivire proportion counter with electrostatic screen of zero potential and unique anticoincidence multiwire proportion counter in lead chamber. The characteristics of the instrument are as follows: Low background (α≤ 0.006 C · P · M/cm2, β≤ 0.03 C · P · M/cm2), low work voltage, low noise, high detective efficiency (>99%), large sensitive area (150 x 100 mm), less dead time, possessing micro accidental anticoincidences, better property of high voltage plateau and discriminating. It has fulfiled the requirements of standard which possesses wide rang (50 C · M · M ∼ 106 C · P · M), high precision (± 5 ∼ 6% for 50 C · P · M ∼ 220 C · P · M, ≤ ± 0.6% for 200 C · P · M ∼ 106 C · P · M); besides, have solved the problem of instability which usualy occurs in same kind of equipments for measuring a sources with less face conductivity

  9. Stoichiometric inhibition of amyloid beta-protein aggregation with peptides containing alternating alpha,alpha-disubstituted amino acids.

    Etienne, Marcus A; Aucoin, Jed P; Fu, Yanwen; McCarley, Robin L; Hammer, Robert P


    We have prepared two peptides based on the hydrophobic core (Lys-Leu-Val-Phe-Phe) of amyloid beta-protein (Abeta) that contain alpha,alpha-disubstituted amino acids at alternating positions, but differ in the positioning of the oligolysine chain (AMY-1, C-terminus; AMY-2, N-terminus). We have studied the effects of AMY-1 and AMY-2 on the aggregation of Abeta and find that, at stoichiometric concentrations, both peptides completely stop Abeta fibril growth. Equimolar mixtures of AMY-1 and Abeta form only globular aggregates as imaged by scanning force microscopy and transmission electron microscopy. These samples show no signs of protofibrillar or fibrillar material even after prolonged periods of time (4.5 months). Also, 10 mol % of AMY-1 prevents Abeta self-assembly for long periods of time; aged samples (4.5 months) show only a few protofibrillar or fibrillar aggregates. Circular dichroism spectroscopy of equimolar mixtures of AMY-1 and Abeta show that the secondary structure of the mixture changes over time and progresses to a predominantly beta-sheet structure, which is consistent with the design of these inhibitors preferring a sheet-like conformation. Changing the position of the charged tail on the peptide, AMY-2 interacts with Abeta differently in that equimolar mixtures form large ( approximately 1 mum) globular aggregates which do not progress to fibrils, but precipitate out of solution. The differences in the aggregation mediated by the two peptides is discussed in terms of a model where the inhibitors act as cosurfactants that interfere with the native ability of Abeta to self-assemble by disrupting hydrophobic interactions either at the C-terminus or N-terminus of Abeta. PMID:16536517

  10. Gross alpha and gross beta activity in the products and by-product of amang tin tailings process

    Gross alpha and gross beta activities were determined for mineral samples collected from five amang tailing factories. The measured activity of alpha ranged from 31 to 220,000 Bq kg-1 with an average 9,154 Bq kg-1, whereas for beta activity ranged from 9 to 552,000 Bq kg-1 with an average 19,811 Bq kg-1. The higher gross alpha and gross beta observed of monazite while the lowest recorded of waste (sand) and pyrite for gross alpha and gross beta activity respectively. The minimum detectable activities were 180 and 40 Bq kg-1 for gross alpha and gross beta respectively. (author)

  11. Crystal structure of 2-chloroacetamide (. cap alpha. form): a reinvestigation

    Kalyanaraman, B.; Kispert, L.D.; Atwood, J.L.


    The crystal structure of the ..cap alpha.. form of 2-chloroacetamide, grown by sublimation, has been determined from three-dimensional counter data and refined by full-matrix least-squares techniques. The crystals belong to the monoclinic space group P2/sub 1//c with a = 10.263(8), b = 5.142(5), c = 7.458(6) A, ..beta.. = 98.72(4)/sup 0/, and D/sub x/ = 1.60 g cm/sup -3/ for Z = 4. The final R factor for 518 observed reflections is 0.037. The molecule exists as a hydrogen-bonded dimer in the crystal structure. The configuration of atoms C(1), C(2), O, and N is planar to within 0.008 A, and the Cl-C(1)-C(2)-O dihedralangle equals 168/sup 0/. The dimeric hydrogen bonding as well as the CH/sub 2/ conformation favors the stabilization of a transient oxygen-centered radical. 3 figures, 3 tables.

  12. Effect of tissue-specific acetylcholinesterase inhibitor C-547 on alpha 3 beta 4 and alpha beta epsilon delta acetylcholine receptors in COS cells

    Lindovský, Jiří; Petrov, K.; Krůšek, Jan; Reznik, V.S.; Nikolsky, E. E.; Vyskočil, František


    Roč. 688, 1-3 (2012), s. 22-26. ISSN 0014-2999 R&D Projects: GA MŠk(CZ) LC554; GA ČR(CZ) GA202/09/0806; GA AV ČR(CZ) IAA500110905; GA AV ČR(CZ) IAA100110501; GA AV ČR(CZ) IAA5011411 Institutional research plan: CEZ:AV0Z50110509 Institutional support: RVO:67985823 Keywords : nicotinic ACh receptor * alpha 3 beta 4 * alpha beta epsilon delta * C-547 * anti-cholinesterase Subject RIV: ED - Physiology Impact factor: 2.592, year: 2012

  13. Alpha and beta dose-rate determination using a gas proportional counter

    The use of proportional gas detectors for determination of the alpha (α) and beta (β) dose rate (due to U, Th and K) of pottery and sediment samples in luminescence and ESR dating was investigated. Alpha and beta count-rate measurements on standard powders of U, Th and K at two different counter voltages, low voltage in which the system detects α-particles and β-particles using different pulse height regions, allow the determination of conversion coefficients that relate count rates to dose rates in samples. The conversion coefficients were applied to the alpha and beta count rates measured on different types of test samples. Analysis of the results shows a remarkable accuracy in the evaluation of the beta dose rates. However, under both measurement conditions (low and high voltage), the alpha dose rates were found to deviate from the expected values to the extent that this procedure must be considered unusable at present. (Author)

  14. Early and continuing effects of combined alpha and beta irradiation of the lung:

    Scott, B.R.; Hahn, F.F.; Snipes, M.B.; Newton, G.J.; Eidson, A.F.; Mauderly, J.L.; Boecker, B.B.


    This report summarizes an inhalation exposure experiment that concerns early and continuing effects of combined alpha and beta irradiation of the lung of rats. Both morbidity at 18 months and mortality within 18 months after exposure were examined for rats exposed to the beta-emitter /sup 147/Pm, the alpha-emitter /sup 238/Pu, or both combined. The results were used to validate hazard-function models that were developed (1)for pulmonary functional morbidity at 18 months and (2) for lethality from radiation pneumonitis and pulmonary fibrosis within 18 months. Both models were found to adequately predict the experimental observations after combined chronic alpha and beta irradiation of the lung. A relative biological effectiveness of approximately 7 was obtained for /sup 238/Pu alpha radiation compared to /sup 147/Pm beta radiation for both pulmonary functional morbidity and lethality from radiation pneumonitis and pulmonary fibrosis. 12 refs., 16 figs., 11 tabs.

  15. Measurement of the branching ratio for beta-delayed alpha decay of 16N

    Refsgaard, J; Dijck, E A; Fynbo, H O U; Lund, M V; Portela, M N; Raabe, R; Randisi, G; Renzi, F; Sambi, S; Sytema, A; Willmann, L; Wilschut, H W


    While the 12C(a,g)16O reaction plays a central role in nuclear astrophysics, the cross section at energies relevant to hydrostatic helium burning is too small to be directly measured in the laboratory. The beta-delayed alpha spectrum of 16N can be used to constrain the extrapolation of the E1 component of the S-factor; however, with this approach the resulting S-factor becomes strongly correlated with the assumed beta-alpha branching ratio. We have remeasured the beta-alpha branching ratio by implanting 16N ions in a segmented Si detector and counting the number of beta-alpha decays relative to the number of implantations. Our result, 1.49(5)e-5, represents a 25% increase compared to the accepted value and implies an increase of 14% in the extrapolated S-factor.

  16. Total alpha and beta activity of air and fallout in Belgrade from 2006 to 2008

    The results of radioactivity control of air and fallout in Belgrade from 2006 to 2008 are presented. The measurements were carried out by low-background proportional gas alpha beta counter PIC-WPC-9550. The system was calibrated with 241Am for total alpha and 90Sr for total beta activity measurements. Efficiency for α and β activity measurement was 31% and 46%, respectively. Monthly average values of the total alpha and beta activity in air varied between 0.003 and 0.053 mBq/m3 and between 0.02 and 0.40 mBq/m3, respectively. Monthly average of the total alpha and beta activity of fallout varied between 0.022 and 0.55 Bq/m2 and between 0.15 and 4.7 Bq/m2, respectively. (author)

  17. Thermomechanical treatment of {beta}-treated Zircaloy-4 within the upper {alpha}-range; Traitements thermomecaniques dans le haut domaine {alpha} du zircaloy-4 trempe-{beta}

    Chauvy, C


    Zircaloy-4 is a Zr base alloy mainly used for nuclear applications. This study deals with its behaviour during forming, with a special interest for physical mechanisms acting in the upper {alpha}-range. The {beta}-treated Zircaloy-4 is first described in terms of microstructure and texture. The {alpha} plates are organised in colonies with alternating crystallographic orientations. The Burgers relationships have also been checked. The mechanical behaviour shows two distinct domains (with or without hardening). This could be linked to interactions between the solutes (Sn, O) and mobile dislocations. The evolution of crystallographic texture is characterised by X-ray diffraction. At 550 C, twinning is shown to be the main deformation mechanism under specific experimental conditions. Globularization of the initial lamellar structure is identified as a continuous dynamic recrystallization process, more efficient at higher temperature. High strains are necessary to achieve this phenomenon but meta-dynamic recrystallization can also be used to obtain an equiaxed microstructure after limited strains. (author)

  18. Synthesis of 7 alpha- and 7 beta-spermidinylcholesterol, squalamine analogues.

    Choucair, B; Dherbomez, M; Roussakis, C; El-kihel, L


    Stereoselective synthesis of squalamine dessulfates analogues, 7 alpha and 7 beta-N-[3N-(4-aminobutyl) aminopropyl]aminocholesterol are reported, using 7 alpha and 7 beta-aminocholesterol as a key intermediate. It's the first example in which the position of spermidine is modified at the steroid ring. These molecules showed a comparable antibacteria and fungi activities to squalamine. Then, they have a cytotoxic activity on a human non-small cell bronchopulmonary carcinoma line (NSCLC-N6). PMID:15261272

  19. Monocytic cells synthesize, adhere to, and migrate on laminin-8 (alpha 4 beta 1 gamma 1).

    Pedraza, C; Geberhiwot, T; Ingerpuu, S; Assefa, D; Wondimu, Z; Kortesmaa, J; Tryggvason, K; Virtanen, I; Patarroyo, M


    Laminins, a growing family of large heterotrimeric proteins with cell adhesive and signaling properties, are major components of vascular and other basement membranes. Expression, recognition, and use of laminin isoforms by leukocytes are poorly understood. In monoblastic THP-1 cells, transcripts for laminin gamma(1)-, beta(1)-, and alpha(4)-chains were detected by RT-PCR. Following immunoaffinity purification on a laminin beta(1) Ab-Sepharose column, laminin beta(1)- (220 kDa), gamma(1)- (200 kDa), and alpha(4)- (180/200 kDa) chains were detected by Western blotting in THP-1 cells and in two other monoblastic cell lines, U-937 and Mono Mac 6. After cell permeabilization, a mAb to laminin gamma(1)-chain reacted with practically all blood monocytes by immunofluorescence flow cytometry, and laminin-8 (alpha(4)beta(1)gamma(1)) could be isolated also from these cells. Monoblastic JOSK-I cells adhered constitutively to immobilized recombinant laminin-8, less than to laminin-10/11 (alpha(5)beta(1)gamma(1)/alpha(5)beta(2)gamma(1)) but to a higher level than to laminin-1 (alpha(1)beta(1)gamma(1)). Compared with the other laminin isoforms, adhesion to laminin-8 was preferentially mediated by alpha(6)beta(1) and beta(2) integrins. Laminin-8 and, to a lower extent, laminin-1 promoted spontaneous and chemokine-induced migration of blood monocytes, whereas laminin-10/11 was inhibitory. Altogether, the results indicate that leukocytes, as other cell types, are able to synthesize complete laminin molecules. Expression, recognition, and use of laminin-8 by leukocytes suggest a major role of this laminin isoform in leukocyte physiology. PMID:11067943

  20. Theta, alpha and beta burst transcranial magnetic stimulation: brain modulation in tinnitus

    Dirk De Ridder, Elsa van der Loo, Karolien Van der Kelen, Tomas Menovsky, Paul van de Heyning, Aage Moller


    Full Text Available Introduction: Some forms of tinnitus are considered to be auditory phantom phenomena related to reorganization and hyperactivity of the auditory central nervous system. Repetitive transcranial magnetic stimulation (rTMS is a non-invasive tool capable of modulating human brain activity, using single pulse or burst stimuli. Burst rTMS has only been performed in the theta range, and has not been used clinically. The authors analyze whether burst TMS at theta (5 Hz, alpha (10 Hz and beta (20 Hz frequencies can temporarily suppress narrow band noise/white noise tinnitus, which has been demonstrated to be intractable to tonic stimulation. Methods: rTMS is performed both in tonic and burst mode in 46 patients contralateral to the tinnitus side, at 5, 10 and 20 Hz. Fourteen placebo negative rTMS responders are further analyzed. Results: In 5 patients, maximal tinnitus suppression is obtained with theta, in 2 with alpha and in 7 with beta burst stimulation. Burst rTMS suppresses narrow band/white tinnitus much better than tonic rTMS t(13=6.4, p<.000. Women experience greater suppression of their tinnitus with burst stimulation than men, t(12=2.9, p<.05. Furthermore left sided tinnitus is perceived as more distressing on the TQ than right sided tinnitus, t(12=3.2, p<.01. The lower the tinnitus pitch the more effectively rTMS suppresses tinnitus(r=-0.65, p<0.05. Discussion: Burst rTMS can be used clinically, not only theta burst, but also alpha and beta burst. Burst rTMS is capable of suppressing narrow band/white noise tinnitus very much better than tonic rTMS. This could be due the simple fact that burst neuromodulation is more powerful than tonic neuromodulation or to a differential effect of burst and tonic stimulation on the lemniscal and extralemniscal auditory system. In some patients only alpha or beta burst rTMS is capable of suppressing tinnitus, and theta burst not. Therefore in future rTMS studies it could be worthwhile not to limit burst

  1. Congruences between modular forms given by the divided beta family in homotopy theory

    Behrens, Mark


    We characterize the 2-line of the p-local Adams-Novikov spectral sequence in terms of modular forms satisfying a certain explicit congruence condition for primes p > 3. We give a similar characterization of the 1-line, reinterpreting some earlier work of A. Baker and G. Laures. These results are then used to deduce that, for l a prime which generates the p-adic units, the spectrum Q(l) detects the alpha and beta families in the stable stems.

  2. Predicting dust extinction properties of star-forming galaxies from H-alpha/UV ratio

    Koyama, Yusei; Hayashi, Masao; Shimakawa, Rhythm; Yamamura, Issei; Egusa, Fumi; Oi, Nagisa; Tanaka, Ichi; Tadaki, Ken-ichi; Takita, Satoshi; Makiuti, Sin'itirou


    Using star-forming galaxies sample in the nearby Universe (0.02alpha-to-FUV flux ratio. We find that the H-alpha dust extinction (A(Ha)) derived with H-alpha/H-beta ratio (Balmer decrement) increases with increasing H-alpha/UV ratio as expected, but there remains a considerable scatter around the relation, which is largely dependent on stellar mass and/or H-alpha equivalent width (EW(Ha)). At fixed H-alpha/UV ratio, galaxies with higher stellar mass (or galaxies with lower EW(Ha)) tend to be more highly obscured by dust. We quantify this trend and establish an empirical calibration for predicting A(Ha) with a combination of H-alpha/UV ratio, stellar mass and EW(Ha), with which we can successfully reduce the systematic uncertainties accompanying the simple H-alpha/UV approach by ~15-30%. The new recipes proposed in this study will provide a conveni...

  3. Measurement of gross alpha and beta in air filter samples by using liquid scintillation counter

    The determination of gross alpha and gross beta in particulate air filter samples was carried out by alpha, beta discrimination method using Liquid Scintillation Analyzer by setting the PSA value at 55 for 5 ml 0.1 HCl plus 15 ml of Ultima Gold AB cocktail by using 241Am and 90Sr/90Y sources. The standardized method was compared with the gross alpha and gross beta activity determined by conventional method of direct counting with end window G.M. counter and ZnS (Ag). The minimum detectable activity of LSA method was found to be 9.3 mBq and 17.7 mBq for gross alpha and gross beta respectively for 6000 sec compared to the conventional method of 9.8 mBq and 189 mBq respectively at the same counting time. The result of analysis by both method indicate that the alpha, beta discrimination set up of LSA method is highly effective in the determination of low level alpha, beta activity in air filter samples. (author)

  4. Uptake of neutral alpha- and beta-amino acids by human proximal tubular cells

    Jessen, H; Røigaard, H; Jacobsen, Christian


    relatively low. Nor did L-arginine and L-aspartic acid affect the uptake of beta-alanine into AHKE cells. Comparison with the results obtained for normal (NHKE) and immortalized (IHKE) embryonic cells suggested an unaltered expression of the types of transport carriers for neutral alpha- and beta-amino acids...

  5. [Eutopic and ectopic production of glycoprotein hormones alpha and beta subunits].

    Bidart, J M; Baudin, E; Troalen, F; Bellet, D; Schlumberger, M


    Human chorionic gonadotropin (hCG) is a glycoprotein composed of two subunits, alpha and beta, linked together by a covalent bond. Ectopic production of hCG has been described in various histological types of cancer. Actually, these malignant tumors predominantly secrete the free beta subunit (hCG beta) and not hCG. Production of free hCG beta is especially found in patients with bladder, pancreas, uterine and lung tumors. In patients with neuroendocrine tumors, serum levels of free hCG beta are higher in gastrointestinal-pancreatic and lung tumors. The significance of ectopic production of hCG beta--epiphenomena or intrinsic biological role--remains unknown. Several reports on the similar structure of hCG beta and certain growth factors suggest that free hCG beta could have an effect on cell proliferation. Increased serum levels of the free alpha subunit are found mainly in patients with neuroendocrine tumors localized in the gut or lung. Serum levels may also be raised in patients with a pituitary tumor, but such production is often associated with a rise in other pituitary hormones. The free alpha subunit plays a role in embryon development and would stimulate production of prolactin by decidual cells. The free alpha subunit may also play a role in tumor growth. PMID:9239230

  6. Closed-form expressions for moments of a class of beta generalized distributions

    Cordeiro, Gauss M.; Nadarajah, Saralees


    For the first time, we derive explicit closed-form expressions for moments of some beta generalized distributions including the beta gamma, beta normal, beta beta, beta Student t and beta F distributions. These expressions are given as infinite weighted sums of well-known special functions for which numerical routines for computation are available.

  7. Purification and characterization of thermostable beta-mannanase and alpha-galactosidase from Bacillus stearothermophilus.

    Talbot, G; Sygusch, J


    Bacillus stearothermophilus secretes beta-mannanase and alpha-galactosidase enzymatic activities capable of hydrolyzing galactomannan substrates. Expression of the hemicellulase activities in the presence of locust bean gum was sequential, with mannanase activity preceding expression of alpha-galactosidase activity. The hemicellulase activities were purified to homogeneity by a combination of ammonium sulfate fractionation, gel filtration, hydrophobic interaction chromatography, and ion-excha...

  8. Invariant glycines and prolines flanking in loops the strand beta 2 of various (alpha/beta)8-barrel enzymes: a hidden homology?

    Janecek, S


    The question of parallel (alpha/beta)8-barrel fold evolution remains unclear, owing mainly to the lack of sequence homology throughout the amino acid sequences of (alpha/beta)8-barrel enzymes. The "classical" approaches used in the search for homologies among (alpha/beta)8-barrels (e.g., production of structurally based alignments) have yielded alignments perfect from the structural point of view, but the approaches have been unable to reveal the homologies. These are proposed to be "hidden" in (alpha/beta)8-barrel enzymes. The term "hidden homology" means that the alignment of sequence stretches proposed to be homologous need not be structurally fully satisfactory. This is due to the very long evolutionary history of all (alpha/beta)8-barrels. This work identifies so-called hidden homology around the strand beta 2 that is flanked by loops containing invariant glycines and prolines in 17 different (alpha/beta)8-barrel enzymes, i.e., roughly in half of all currently known (alpha/beta)8-barrel proteins. The search was based on the idea that a conserved sequence region of an (alpha/beta)8-barrel enzyme should be more or less conserved also in the equivalent part of the structure of the other enzymes with this folding motif, given their mutual evolutionary relatedness. For this purpose, the sequence region around the well-conserved second beta-strand of alpha-amylase flanked by the invariant glycine and proline (56_GFTAIWITP, Aspergillus oryzae alpha-amylase numbering), was used as the sequence-structural template. The proposal that the second beta-strand of (alpha/beta)8-barrel fold is important from the evolutionary point of view is strongly supported by the increasing trend of the observed beta 2-strand structural similarity for the pairs of (alpha/beta)8-barrel enzymes: alpha-amylase and the alpha-subunit of tryptophan synthase, alpha-amylase and mandelate racemase, and alpha-amylase and cyclodextrin glycosyltransferase. This trend is also in agreement with the

  9. Isothermal and aniso-thermal creep in the {alpha} phase domain, {beta} phase domain and {alpha}+{beta} two phase domain in a Zr-1%NbO alloy; Fluage isotherme et anisotherme dans les domaines monophases ({alpha} et {beta}) et biphases ({alpha} et {beta}) d'un alliage Zr-1%NbO

    Kaddour, D


    The coupling between phase transformation and mechanical behaviour of a Zr-1%NbO alloy was studied using an original experimental device already used in a previous study devoted to the Zy-4 alloy. The Zr-1%NbO alloy undergoes a phase transformation {alpha} (hc) {r_reversible} (cc) typically between 750 and 1000 C. The transformation temperatures were measured in situ by using the resistivity and dilatometry techniques. The isothermal creep behaviour of fuel cladding tubes was studied, first after heating, in the {alpha} phase domain between 650 and 760 C, in the {beta} phase domain between 960 and 1100 C, as well as in the ({alpha} + {beta}) two phase domain between 800 and 900 C. The results are summarized in Ashby deformation mechanism maps. It is confirmed that the {beta} phase is much more sensitive to creep flow than the {alpha} phase. The effect of microstructure on the isothermal creep flow behaviour was then investigated by first applying a thermal cycle involving either a full or a partial transformation from {alpha} to {beta}. It was investigated both in the {alpha} phase domain, and after direct cooling into the ({alpha} + {beta}) phase domain. The behaviour in aniso-thermal conditions was finally studied at heating and cooling rates of 10 and 200 C/min. In both cases, we showed that there is no significant transformation plasticity in the stress range under investigation ({<=} 5 MPa). A finite element model using Voronoi polyhedra and eventually meshing a film of intergranular {beta} phase was used to describe the behaviour of material in the ({alpha} + {beta}) domain in various microstructural states. The model predictions are in good agreement with the experimental results for the microstructure obtained after cooling, but the model underestimates creep deformation in the as-received state. This difference is probably related to the fact that interface sliding is not taken into account in the model. (author)

  10. Integrin alpha3beta1, a novel receptor for alpha3(IV) noncollagenous domain and a trans-dominant Inhibitor for integrin alphavbeta3.

    Borza, Corina M; Pozzi, Ambra; Borza, Dorin-Bogdan; Pedchenko, Vadim; Hellmark, Thomas; Hudson, Billy G; Zent, Roy


    Exogenous soluble human alpha3 noncollagenous (NC1) domain of collagen IV inhibits angiogenesis and tumor growth. These biological functions are attributed to the binding of alpha3NC1 to integrin alphavbeta3. However, in some tumor cells that express integrin alphavbeta3, the alpha3NC1 domain does not inhibit proliferation, suggesting that integrin alphavbeta3 expression is not sufficient to mediate the anti-tumorigenic activity of this domain. Therefore, in the present study, we searched for novel binding receptors for the soluble alpha3NC1 domain in cells lacking alphavbeta3 integrin. In these cells, soluble alpha3NC1 bound integrin alpha3beta1; however, unlike alphavbeta3, alpha3beta1 integrin did not mediate cell adhesion to immobilized alpha3NC1 domain. Interestingly, in cells lacking integrin alpha3beta1, adhesion to the alpha3NC1 domain was enhanced due to activation of integrin alphavbeta3. These findings indicate that integrin alpha3beta1 is a receptor for the alpha3NC1 domain and transdominantly inhibits integrin alphavbeta3 activation. Thus integrin alpha3beta1, in conjunction with integrin alphavbeta3, modulates cellular responses to the alpha3NC1 domain, which may be pivotal in the mechanism underpinning its anti-angiogenic and anti-tumorigenic activities. PMID:16731529

  11. The proportion of hybrid heterodimers in homozygous or doubly heterozygous beta chain variant hemoglobinopathies associated with alpha chain hemoglobin variants.

    Krauss, J S


    Four alpha genes exist on chromosome 16, but one or more of these genes can be deleted in association with Hemoglobin (Hb)G-Philadelphia in cis to alpha-thalassemia-2 in African-Americans. Therefore, the proportion of HbG-Philadelphia in HbG heterozygotes is trimodal at about 25% for alphaGalpha/alpha alpha, 33% for alphaG-/alpha alpha, and 50% for alphaG-/alpha alpha in patients with HbA. Those who are homozygous or doubly heterozygous for beta chain variants (betaX2 or betaXbetaY) have neither HbA nor the alpha chain variant (alphaX2 betaA2), but have hybrid heterodimers (alphaX2 betaX2). The proportion of hybrid heterodimers here should also be trimodal mirroring alpha gene status. Eleven patients were identified: 4 with Hb SSG, 3 with Hb SCG, and 1 each with Hb OCG, HbSSMontgomery, HbSSChicago, and HbSSBourmedes. Heterodimer proportions were: 43.3 +/- 1.5, 33.5 +/- 2.3, and 15.8 +/- 1.1% for 2, 3, and 4 respective alpha genes which had been studied in 8/11 of the patients (r = 0.98), implying that the prime determinant of the proportion of hybrid heterodimers in this patient group is the number of functional alpha genes. PMID:11045763

  12. Music genre preference and tempo alter alpha and beta waves in human non-musicians

    Hunter Gentry


    Full Text Available This study examined the effects of music genre and tempo on brain activation patterns in 10 nonmusicians.Two genres (rock and jazz and three tempos (slowed, medium/normal, andquickened were examined using EEG recording and analyzed through Fast Fourier Transform(FFT analysis. When participants listened to their preferred genre, an increase in alpha waveamplitude was observed. Alpha waves were not significantly affected by tempo. Beta waveamplitude increased significantly as the tempo increased. Genre had no effect on beta waves. Thefindings of this study indicate that genre preference and artificially modified tempo do affectalpha and beta wave activation in non-musicians listening to preselected songs.

  13. Structure and properties of alpha- and beta- CeCuSn: A single-crystal and Mossbauer spectroscopic investigation

    Sebastian, C. Peter; Rayaprol, Sudhindra; Hoffmann, Rolf-Dieter; Rodewald, Ute Ch.; Pape, Tania; Pottgen, Rainer


    Two modifications of CeCuSn were prepared from the elements: the high-temperature (beta) modification crystallizes directly from the quenched sample, while the low-temperature (alpha) modification forms after annealing at 700 deg C for one month. Both modifications were investigated by X-ray powder and single crystal diffraction. We find for alpha-CeCuSn a structure of ZrBeSi type, space group P63/mmc, a = 458.2(1), c = 793.7(2) pm, wR2 = 0.0727, 148 F2 values, 8 variable parameters. In the c...

  14. Synthesis of alpha,beta-unsaturated ketones as chalcone analogues via a S(RN)1 mechanism.

    Curti, Christophe; Gellis, Armand; Vanelle, Patrice


    An electron-transfer chain reaction between 2-nitropropane anion and alpha-bromoketones derived from nitrobenzene and nitrothiophene was demonstrated by mechanistic study and a specific convenient synthetic protocol. Thus, 2-bromo-1-(5-nitrothiophen-2-yl)ethanone or 2-bromo-1-(4-nitrophenyl)ethanone were reacted with several cyclic nitronate anions to form alpha,beta-unsaturated ketones via a S(RN)1 mechanism. This new method can be used to synthesize a wide variety of chalcone analogues. PMID:17851431

  15. Hydrogen and sliding at alpha/beta interfaces of titanium alloys

    Margolin, Harold


    Emerging evidence that the sliding between alpha and beta interfaces reported in both Ti-Mn alloys and the Ti-4.5Al-5Mo-1.5Cr ('Corona 5') alloy at room temperature is associated with hydrogen suggests that this may be a general problem contributing to Ti alloys' room-temperature creep. The present evaluation of experimental data indicates that while the hydrogen is concentrated at the Ti-Mn alloys' beta phase, no hydride formation at the alpha/beta interfaces has been reported for either the Ti-Mn alloys or Corona 5. If a hydrogen flux is needed, sliding at the alpha-beta interfaces should be a function of total hydrogen content in the alloy.

  16. Alpha and beta adrenergic effects on metabolism in contracting, perfused muscle

    Richter, Erik; Ruderman, N B; Galbo, H


    The role of alpha- and beta-adrenergic receptor stimulation for the effect of epinephrine on muscle glycogenolysis, glucose- and oxygen uptake and muscle performance was studied in the perfused rat hindquarter at rest and during electrical stimulation (60 contractions/min). Adrenergic stimulation...... was obtained by epinephrine in a physiological concentration (2.4 X 10(-8) M) and alpha- and beta-adrenergic blockade by 10(-5) M phentolamine and propranolol, respectively. Epinephrine enhanced net glycogenolysis during contractions most markedly in slow-twitch red fibers. In these fibers the effect...... stimulation of alpha-adrenergic receptors and had a positive inotropic effect during contractions which was abolished by alpha- as well as by beta-adrenergic blockade. The results indicate that epinephrine has profound effects on contracting muscle, and that these effects are elicited through different...

  17. alpha4beta2 nicotinic acetylcholine receptors on dopaminergic neurons mediate nicotine reward and anxiety relief

    McGranahan, Tresa M.; Patzlaff, Natalie E.; Grady, Sharon R.; Heinemann, Stephen F.; Booker, T.K.


    Nicotine is the primary psychoactive substance in tobacco and it exerts its effects by interaction with various subtypes of nicotinic acetylcholine receptors (nAChRs) in the brain. One of the major subtypes expressed in brain, the alpha4beta2-nAChR, endogenously modulates neuronal excitability and thereby, modifies certain normal, as well as nicotine-induced, behaviors. Although alpha4-containing nAChRs are widely expressed across the brain, a major focus has been on their roles within midbrain dopaminergic regions involved in drug addition, mental illness and movement control in humans. We developed a unique model system to examine the role of alpha4-nAChRs within dopaminergic neurons by a targeted genetic deletion of the alpha4 subunit from dopaminergic neurons in mice. The loss alpha4 mRNA and alpha4beta2-nAChRs from dopaminergic neurons was confirmed, as well as selective loss of alpha4beta2-nAChR function from dopaminergic but not GABAergic neurons. Two behaviors central to nicotine dependence, reward and anxiety relief, were examined. Alpha4-nAChRs specifically on dopaminergic neurons were demonstrated to be necessary for nicotine reward as measured by nicotine place preference, but not for another drug of addiction, cocaine. Alpha4-nAChRs are necessary for the anxiolytic effects of nicotine in the elevated plus maze and elimination of alpha4-beta2-nAChRs specifically from dopaminergic neurons decreased sensitivity to the anxiolytic effects of nicotine. Deletion of alpha4-nAChRs specifically from dopaminergic neurons also increased sensitivity to nicotine-induced locomotor depression, however nicotine-induced hypothermia was unaffected. This is the first work to develop a dopaminergic specific deletion of a nAChR subunit and examine resulting changes in nicotine behaviors. PMID:21795541

  18. An X11alpha/FSBP complex represses transcription of the GSK3beta gene promoter.

    Lau, Kwok-Fai


    X11alpha is a neuronal adaptor protein that interacts with the amyloid precursor protein (APP) through a centrally located phosphotyrosine binding domain to inhibit the production of Abeta peptide that is deposited in Alzheimer\\'s disease brains. X11alpha also contains two C-terminal postsynaptic density-95, large discs, zona occludens 1 (PDZ) domains, and we show here that through its PDZ domains, X11alpha interacts with a novel transcription factor, fibrinogen silencer binding protein. Moreover, we show that an X11alpha\\/fibrinogen silencer binding protein complex signals to the nucleus to repress glycogen synthase kinase-3beta promoter activity. Glycogen synthase kinase-3beta is a favoured candidate kinase for phosphorylating tau in Alzheimer\\'s disease. Our findings show a new function for X11alpha that may impact on Alzheimer\\'s disease pathogenesis.

  19. Design and device construction for plane tables preparation for counter alpha/beta total

    This work presents the design and assembly of a device for plane tables preparation for quantification alpha/beta total of radioactive waste samples. The determination of the activity index alpha/beta total is used to detect a wide variety of matrices quickly and the concentration of alpha and/or beta emitters of the contained radionuclides in different samples. In particular, the determination of the activity index alpha and beta total of radioactive wastes involves the digestion of samples in aggressive means that will be evaporated to dryness for its quantification. With the purpose of controlling the emission of corrosive gases during the preparation of the plane tables for the quantification of the index alpha and beta total, was designed and built the device in the Radioactive Waste Laboratory that allows to prepare plane tables for proportional counters in a sure and efficient way. The device is constituted by heating equipment, evaporation cylinder and a gases cleaning system. The self-absorption curve got ready starting from the device. (Author)

  20. Rapid determination of gross alpha/beta activity in milk using liquid scintilation counter technique

    Sas Daniel


    Full Text Available Rapid determination of gross alpha and beta emitters in milk by liquid scintillation counter is discussed. This method is based on direct addition of different types of milk into scintillation cocktail and therefore it is very promising for fast determination of alpha/beta activity due to direct alpha and beta separation, measurement in close 4p geometry and without sample treatment. The selected group of radionuclides was chosen with the respect to military significance, radio-toxicity, and possibility of potential misuse. As model radionuclides 241Am, 239Pu, and 90Sr were selected. The Liquid Scintilation Counter Hidex 300 SL equipped with triple-double-coincidence-ratio technique was used for sample measurement. The aim of the work was focused on comparison of different cocktails produced by Hidex and Perkin Elmer, choosing the best cocktail based on our measurement results and adjustment of its appropriate volume. Furthermore, the optimization of ratio between the volume of scintillation cocktail and the volume of urine was investigated with the respect to the model radionuclides. According to the obtained results, the efficiency for alpha emitters was greater than 85% and for beta, greater than 95%. The obtained results allowed this method to be used for rapid determination of gross alpha/beta activity in cases where time is an essence, such as first responders or mass-scale samples, where ordinary means suffer from lack of capacity or simply collapse under the onslaught.

  1. SU-E-J-03: A Comprehensive Comparison Between Alpha and Beta Emitters for Cancer Radioimmunotherapy

    Huang, C.Y. [University of Sydney, Camperdown, NSW (Australia); Guatelli, S [University of Wollongong, Wollongong, NSW (Australia); Oborn, B [Illawarra Cancer Care Centre, Wollongong, NSW (Australia); Allen, B [University of Western Sydney, Liverpool, NSW (Australia)


    Purpose: The purpose of this study is to perform a comprehensive comparison of the therapeutic efficacy and cytotoxicity of alpha and beta emitters for Radioimmunotherapy (RIT). For each stage of cancer development, specific models were built for the separate objectives of RIT to be addressed:a) kill isolated cancer cells in transit in the lymphatic and vascular circulation,b) regress avascular cell clusters,c) regress tumor vasculature and tumors. Methods: Because of the nature of short range, high LET alpha and long energy beta radiation and heterogeneous antigen expression among cancer cells, the microdosimetric approach is essential for the RIT assessment. Geant4 based microdosimetric models are developed for the three different stages of cancer progression: cancer cells, cell clusters and tumors. The energy deposition, specific energy resulted from different source distribution in the three models was calculated separately for 4 alpha emitting radioisotopes ({sup 211}At, {sup 213}Bi, {sup 223}Ra and {sup 225}Ac) and 6 beta emitters ({sup 32}P, {sup 33}P, {sup 67}Cu, {sup 90}Y, {sup 131}I and {sup 177}Lu). The cell survival, therapeutic efficacy and cytotoxicity are determined and compared between alpha and beta emitters. Results: We show that internal targeted alpha radiation has advantages over beta radiation for killing isolated cancer cells, regressing small cell clusters and also solid tumors. Alpha particles have much higher dose specificity and potency than beta particles. They can deposit 3 logs more dose than beta emitters to single cells and solid tumor. Tumor control probability relies on deep penetration of radioisotopes to cancer cell clusters and solid tumors. Conclusion: The results of this study provide a quantitative understanding of the efficacy and cytotoxicity of RIT for each stage of cancer development.

  2. SU-E-J-03: A Comprehensive Comparison Between Alpha and Beta Emitters for Cancer Radioimmunotherapy

    Purpose: The purpose of this study is to perform a comprehensive comparison of the therapeutic efficacy and cytotoxicity of alpha and beta emitters for Radioimmunotherapy (RIT). For each stage of cancer development, specific models were built for the separate objectives of RIT to be addressed:a) kill isolated cancer cells in transit in the lymphatic and vascular circulation,b) regress avascular cell clusters,c) regress tumor vasculature and tumors. Methods: Because of the nature of short range, high LET alpha and long energy beta radiation and heterogeneous antigen expression among cancer cells, the microdosimetric approach is essential for the RIT assessment. Geant4 based microdosimetric models are developed for the three different stages of cancer progression: cancer cells, cell clusters and tumors. The energy deposition, specific energy resulted from different source distribution in the three models was calculated separately for 4 alpha emitting radioisotopes (211At, 213Bi, 223Ra and 225Ac) and 6 beta emitters (32P, 33P, 67Cu, 90Y, 131I and 177Lu). The cell survival, therapeutic efficacy and cytotoxicity are determined and compared between alpha and beta emitters. Results: We show that internal targeted alpha radiation has advantages over beta radiation for killing isolated cancer cells, regressing small cell clusters and also solid tumors. Alpha particles have much higher dose specificity and potency than beta particles. They can deposit 3 logs more dose than beta emitters to single cells and solid tumor. Tumor control probability relies on deep penetration of radioisotopes to cancer cell clusters and solid tumors. Conclusion: The results of this study provide a quantitative understanding of the efficacy and cytotoxicity of RIT for each stage of cancer development

  3. Ion-Induced Dipole Interactions and Fragmentation Times : C$\\alpha$ -C$\\beta$ Chromophore Bond Dissociation Channel

    Soorkia, Satchin; Kumar, Sunil; Pérot-Taillandier, Marie; Lucas, Bruno; Jouvet, Christophe; Barat, Michel; Fayeton, Jacqueline A


    The fragmentation times corresponding to the loss of the chromophore (C$\\alpha$-- C$\\beta$ bond dissociation channel) after photoexcitation at 263 nm have been investigated for several small peptides containing tryptophan or tyrosine. For tryptophan-containing peptides, the aromatic chromophore is lost as an ionic fragment (m/z 130), and the fragmentation time increases with the mass of the neutral fragment. In contrast, for tyrosine-containing peptides the aromatic chromophore is always lost as a neutral fragment (mass = 107 amu) and the fragmentation time is found to be fast (\\textless{}20 ns). These different behaviors are explained by the role of the postfragmentation interaction in the complex formed after the C$\\alpha$--C$\\beta$ bond cleavage.

  4. Modulator effects of interleukin-1beta and tumor necrosis factor-alpha on AMPA-induced excitotoxicity in mouse organotypic hippocampal slice cultures

    Bernardino, Liliana; Xapelli, Sara; Silva, Ana P;


    The inflammatory cytokines interleukin-1beta and tumor necrosis factor-alpha (TNF-alpha) have been identified as mediators of several forms of neurodegeneration in the brain. However, they can produce either deleterious or beneficial effects on neuronal function. We investigated the effects of...... concentration of mouse recombinant TNF-alpha (10 ng/ml) enhanced excitotoxicity when the cultures were simultaneously exposed to AMPA and to this cytokine. Decreasing the concentration of TNF-alpha to 1 ng/ml resulted in neuroprotection against AMPA-induced neuronal death independently on the application...

  5. Effect of Disturbance Regime on Alpha and Beta Diversity of Rock Pools

    Annie Séguin


    Full Text Available Measures of alpha diversity are more frequently used to detect environmental changes and subsequent impacts on biodiversity, while measures based on variability (beta diversity are said to be more appropriate for detecting those impacts. Theory predicts that beta diversity should increase with disturbance frequency in patchy communities. Our objective in this study was to experimentally determine the effect of high and low disturbance regimes, frequency and intensity combined, on marine benthic alpha and beta diversity. The experiment was conducted in a rock pool system of the St. Lawrence estuary, Canada. Rock pools were disturbed by (1 nutrient enrichment and (2 draining according to three disturbance regimes (none, low, high. Disturbance regimes had little or no effect on alpha diversity of benthic algae and sessile animals. However, the low regime of nutrient enrichment induced greater within-group beta diversity than the reference rock pools, while the high disturbance regime induced equal or even smaller within-group beta diversity compared to the reference. Draining had an opposite effect on benthic beta diversity, with a greater variability of the community structure under the high regime of disturbance. Taking into account the effect of disturbance regimes on beta diversity could provide a useful diagnostic for disturbed benthic communities.

  6. Alpha9beta1 integrin in melanoma cells can signal different adhesion states for migration and anchorage

    Lydolph, Magnus C; Morgan-Fisher, Marie; Høye, Anette M;


    Cell surface integrins are the primary receptors for cell migration on extracellular matrix, and exist in several activation states regulated in part by ectodomain conformation. The alpha9 integrin subunit, which pairs only with beta1, has specific roles in the immune system and may regulate cell......beta1 integrin- and Rho kinase-dependent focal adhesion and stress fibre formation, suggesting that the activation status of alpha9beta1 integrin was altered. The effect of manganese ions in promoting focal adhesion formation was reproduced by beta1 integrin activating antibody. The alpha9beta1...

  7. BEGe detector response to alpha and beta-radiation near its p{sup +} electrode

    Bode, Tobias; Agostini, Matteo; Barnabe-Heider, Marik; Budjas, Dusan; Schoenert, Stefan [Technische Universitaet Muenchen (Germany); Collaboration: GERDA-Collaboration


    In Phase II of the GERDA (Germanium Detector Array) experiment Broad Energy Germanium (BEGe) detectors will continue the search for the neutrinoless double beta decay (0{nu}{beta}{beta}) of {sup 76}Ge. The main feature of these detectors is their small p{sup +} electrode used for signal read-out. Due to the thin dead layer of the p{sup +} contact, surface events close to this electrode represent a potential background for the search of 0{nu}{beta}{beta}. A study was conducted to determine the response of the detector to alpha and beta-radiation using movable collimated sources within a custom-build cryostat. Preliminary results of this study and a possible method to discriminate these events will be presented.

  8. The Assay of Alpha- and Beta-Emitters by Means of Scintillating Ion-Exchange Resins

    The development of scintillating resins (SIER) has provided a unique system for the detection and counting of alpha- and beta-ray emitting nuclides. The property of ion exchange permits the concentration of ionic radionuclides from aqueous solutions of widely varying chemical conditions. The property of scintillation in response to the emitted particles allows for the detection of the adsorbed radionuclides. Both anionic and cationic SIER have been developed and possess the strongly basic, quaternary ammonium group and the strongly acidic, aryl sulphonic group respectively. Therefore, the voluminous literature on the uses of commercially available ion-exchange resins can be applied in many cases to SIER. The availability of both anionic and cationic resins presents the possibility of a method for the adsorption of almost all elements except the rare gases. The stability of SIER is such that it can be used in solution of strong sodium hydroxide, concentrated hydrochloric and sulphuric acids as well as 6N nitric acid at 25°C for short periods (3 - 4 h) of time. SIER is readily adapted for counting with the available scintillation counting apparatus. The activated resin can be counted in a plastic (or glass) cup coupled to a photomultiplier tube and an electronic pulse counter. It can also be transferred to a glass vial, immersed in aqueous alcohol or toluene, and counted in a liquid scintillation counter. SIER in the form of small spherical beads permits the use of counting vessels with many different geometric configurations. Both alpha- and beta-ray emitting nuclides have been efficiently adsorbed and counted using these methods. The low-energy beta-emitters, such as 63Ni and 14C, have been counted with 12 and 35%efficiencies respectively. The alpha-emitters of 239Pu and 237Np have been adsorbed and efficiently counted (70-90%) on both the anionic and cationic resins. 14C-tagged amino acids have also been counted at over 20% efficiency using a liquid

  9. Calibration and validation of measures a total alpha beta counter in the tunisian mineral water

    The risks due to contamination of mineral waters are essentially risk internal radiation following ingestion of radionuclides which brought us in this study to determine the global alpha and beta of the Tunisian mineral water. We used an alpha beta global counter. The results obtained by this technique have shown that alpha activity of these 10 waters are all lower than 50 mBq / l and are varied between 3.75 and 8.4 mBq / l and beta activity was found only 9 waters are also lower than 50 mBq / l (between 7.17 and 18.25) when only one is between 100 and 500 mBq / l (101.17).

  10. Assessment of Base Line Concentrations for Trace Elements and Total Alpha, Beta Gross for Some Herbs

    Five marked brands of drinking herbs, commonly consumed by Egyptian population were collected from local market. Concentration of essential and toxic elements have been measured by atomic absorption spectrometry (AAS). Also, the total alpha and beta gross activities in all samples were measured using ultra low level liquid scintillation counting system (LSC). Cinnamon was found to contain relatively high amounts of essential as well as toxic elements but the measurement using LSC revealed no detection for both alpha and beta gross activity. The annual effective doses for different herbs were also calculated referring to the dose conversion factor (dose per unit intake) for both alpha and beta gross activity when dealing with naturally occurring radionuclides. The study also shows that these herbs are additional source of trace heavy elements intake

  11. Environmental hydrogen embrittlement of an alpha-beta titanium alloy - Effect of microstructure.

    Nelson, H. G.; Williams, D. P.; Stein, J. E.


    Study of environmental hydrogen embrittlement of a Ti-6 Al-4 alloy as a function of test displacement rate and of variations in alpha-beta microstructure. Embrittlement in low-pressure (about 1 atm) gaseous hydrogen was inversely dependent on test displacement rate and strongly dependent on microstructure. At a given displacement rate, microstructures having a continuous alpha-phase matrix were less severely embrittled than those having a continuous beta-phase matrix. Further, brittle fracture occurred in the former microstructures by transgranular cleavage and in the latter microstructures by intergranular separation. These observations are consistent with previous studies made on slow strain-rate embrittlement of hydrogen-charged titanium alloys and are explained in terms of relative hydrogen transport rates within the alpha-phase and beta-phase titanium.

  12. Preparation and validation of gross alpha/beta samples used in EML's quality assessment program

    A set of water and filter samples have been incorporated into the existing Environmental Measurements Laboratory's (EML) Quality Assessment Program (QAP) for gross alpha/beta determinations by participating DOE laboratories. The participating laboratories are evaluated by comparing their results with the EML value. The preferred EML method for measuring water and filter samples, described in this report, uses gas flow proportional counters with 2 in. detectors. Procedures for sample preparation, quality control and instrument calibration are presented. Liquid scintillation (LS) counting is an alternative technique that is suitable for quantifying both the alpha (241Am, 230Th and 238Pu) and beta (90Sr/90Y) activity concentrations in the solutions used to prepare the QAP water and air filter samples. Three LS counting techniques (Cerenkov, dual dpm and full spectrum analysis) are compared. These techniques may be used to validate the activity concentrations of each component in the alpha/beta solution before the QAP samples are actually prepared

  13. A preliminary study of gross alpha/beta activity concentrations in drinking waters from Albania

    A pilot study involving screening measurements of gross alpha/beta activity concentration in drinking water was performed in 12 cities with the highest population density in Albania. The aim of this study was to develop a first insight regarding the radiological quality of drinking and bottled water supplies. The tap and bottled water samples investigated are acceptable for consumption, complying with the WHO recommendations for drinking water. The average gross alpha and beta activity concentrations were 36-18+37 and 269-150+337 mBq/L, respectively in tap waters. While for bottled water the gross alpha and beta activities were respectively 39-23+55 and 220-132+336 mBq/L. The data obtained can provide information for authorities regarding the quality of drinking water and a baseline for future contaminations. (author)

  14. Dose-response effects of estrogenic mycotoxins (zearalenone, alpha- and beta-zearalenol on motility, hyperactivation and the acrosome reaction of stallion sperm

    Colenbrander Ben


    . Conversely, zearalenone and 17beta-estradiol did not induce the acrosome reaction but induced hyperactive motility albeit to a different extent. Conclusions Apparently, the mycotoxin zearalenone has 17beta-estradiol-like estrogenic activity that enables it to induce hyperactivated motility of equine sperm cells, whereas the zearalenol derivatives induce premature completion of the acrosome reaction and thereby adversely affect stallion sperm physiology. The alpha form of zearalenol still possessed the estrogenic ability to induce hyperactivated motility, whereas its beta stereo-isomere had lost this property.

  15. Purification and characterization of extremely thermostable beta-mannanase, beta-mannosidase, and alpha-galactosidase from the hyperthermophilic eubacterium Thermotoga neapolitana 5068.

    Duffaud, G D; McCutchen, C M; Leduc, P; Parker, K N; Kelly, R M


    Thermostable and thermoactive beta-mannanase (1,4-beta-D-mannan mannanohydrolase [EC]), beta-mannosidase (beta-D-mannopyranoside hydrolase [EC]) and alpha-galactosidase (alpha-D-galactoside galactohydrolase [EC]) were purified to homogeneity from cell extracts and extracellular culture supernatants of the hyperthermophilic eubacterium Thermotoga neapolitana 5068 grown on guar gum-based media. The beta-mannanase was an extracellular monomeric enzyme with a molecular ...

  16. A genetic combination of silent beta-thalassaemia, high Hb A2 beta-thalassaemia, and single alpha globin gene deletion causing mild thalassaemia intermedia.

    R. Galanello; Maccioni, L; ROSATELLI, M. C.; Ibba, P; Nurchi, A M; Cao, A


    This paper reports a Sardinian patient, who was a compound heterozygote for silent beta-thalassaemia and high Hb A2 beta o-thalassaemia with the clinical phenotype of mild thalassaemia intermedia; alpha globin gene mapping showed a single alpha globin gene deletion. The reduced alpha globin chain output resulted in more balanced globin chain synthesis, which in turn accounted for the mild clinical phenotype.

  17. Transport of alpha- and beta-D-glucose by the intact human red cell

    The kinetics of alpha- and beta-D-glucose mutarotation and the transport of these anomers by intact human red cells were determined at 0.6 and 36.6 degrees C. The mutarotation coefficients for alpha- and beta-D-glucose in cell-free tris(hydroxymethyl)aminomethane medium (pH 7.4) at 0.6 degrees C are (2.25 +/- 0.2) and (1.73 +/- 0.42) X 10(-3) min-1, respectively, and at 36.6 degrees C are (69 +/- 12) and (75 +/- 5) X 10(-3) min-1, respectively. These values are in good agreement with previous estimates. At 0.6 degrees C, the red cell contains no detectable mutarotase activity. Initial rates of sugar uptake were measured by using radiolabeled D-glucose and time courses of uptake by turbidimetry. The time courses of alpha- and beta-D-glucose and an equilibrium mixture of alpha- and beta-D-glucose infinite-cis entry are identical at 0.66 degrees C (n = 41) where negligible mutarotation is observed. The apparent Ki values for inhibition of radiolabeled D-glucose initial uptake by unlabeled alpha- or beta-D-glucose at 0.6 degrees C are identical (1.6 mM). The calculated Vmax parameters for uptake of the radiolabeled anomers at this temperature are also indistinguishable. The time courses of infinite-cis alpha- and beta-D-glucose uptake at 36.66 degrees C are identical (n = 40). While D-glucose mutarotation is more rapid at this temperature, the anomers of D-glucose are not transported differently by the red cell hexose transfer system

  18. Alpha/beta pulse shape discrimination in plastic scintillation using commercial scintillation detectors

    Activity determination in different types of samples is a current need in many different fields. Simultaneously analysing alpha and beta emitters is now a routine option when using liquid scintillation (LS) and pulse shape discrimination. However, LS has an important drawback, the generation of mixed waste. Recently, several studies have shown the capability of plastic scintillation (PS) as an alternative to LS, but no research has been carried out to determine its capability for alpha/beta discrimination. The objective of this study was to evaluate the capability of PS to discriminate alpha/beta emitters on the basis of pulse shape analysis (PSA). The results obtained show that PS pulses had lower energy than LS pulses. As a consequence, a lower detection efficiency, a shift to lower energies and a better discrimination of beta and a worst discrimination of alpha disintegrations was observed for PS. Colour quenching also produced a decrease in the energy of the particles, as well as the effects described above. It is clear that in PS, the discrimination capability was correlated with the energy of the particles detected. Taking into account the discrimination capabilities of PS, a protocol for the measurement and the calculation of alpha and beta activities in mixtures using PS and commercial scintillation detectors has been proposed. The new protocol was applied to the quantification of spiked river water samples containing a pair of radionuclides (3H-241Am or 90Sr/90Y-241Am) in different activity proportions. The relative errors in all determinations were lower than 7%. These results demonstrate the capability of PS to discriminate alpha/beta emitters on the basis of pulse shape and to quantify mixtures without generating mixed waste.

  19. Gross alpha and beta activities in potable waters used by pharmaceutical companies in India

    This paper presents the gross alpha and gross beta radioactivity present in potable waters used by pharmaceutical firms from different states of India. A three year analysis in more than 90 water samples indicated that the gross alpha activity was observed to be in the range of <1 to 42.9±2.5mBq/l while gross beta activity was in the range of <20 to 67.6±2 mBq/l. Higher level of activity was observed in Goa waters. However the activities were observed to be within the limits of drinking water regulations as per USEPA 40CFR.141 and WHO regulations. (author)

  20. GFM-II large area surface monitor for alpha beta contamination

    Du Xiang Yang; Han Shu Ping; Zhang Xia


    GFM-II large area surface monitor for alpha/beta contamination is equipped with four independent detecting channels, each channel consists one probe and one charge sensitive amplifier. The pancake probe is flow gas proportional counter tubes array. Total active area of the instrument is 1000 cm sup 2. This instrument has an rolling frame, so it can move rapidly on flat ground. Its characteristics is that: 1) Use flow gas proportional counter array instead of single counter, 2) Lower working voltage, 3) Simultaneously rapid measurement for alpha/beta

  1. Interleukin-1 alpha, interleukin-1 beta and interleukin-8 gene expression in human aural cholesteatomas.

    Kim, C S; Lee, C H; Chung, J W; Kim, C D


    Bone destruction is a common characteristic feature of chronic otitis media, especially aural cholesteatoma. A number of immunohistochemical studies have suggested that interleukin-1 (IL-1) may be responsible for cholesteatomatous bone destruction. We designed this study to present the mRNA expression patterns of IL-1 alpha, IL-1 beta, and IL-8, which can induce and activate the leukocyte, the major reservoir of potent proteolytic enzymes. Total RNAs were extracted from aural cholesteatomas, external auditory canal skin (EACS), postauricular skin (PAS), and granulation tissues and transcribed into cDNAs. cDNAs were amplified by using PCR technique with primers for IL-1 alpha, IL-1 beta, IL-8, and beta-actin. Amplified products were hybridized with each internal probe and the relative density was measured. In granulation tissues, the relative density of IL-1 alpha was greater than that of other tissues. The ratio of IL-1 beta and IL-8 of aural cholesteatoma was significantly higher than that of EACS and PAS. We suggest that both of IL-1 alpha and IL-1 beta may play a role in the pathological changes, and that IL-8, which is mainly produced from cholesteatomatous epithelium, may have an important role in the pathological changes of cholesteatomas. PMID:8725537

  2. The Crystal Structure of CD8alpha,Beta in Complex With YTS156.7.7 Fab And Interaction With Other CD8 Antibodies Define the Binding Mode of CD8alpha,Beta to MHC Class I

    Shore, D.A.; Issafras, H.; Landais, E.; Teyton, L.; Wilson, I.A.


    The CD8{alpha}{beta} heterodimer interacts with class I pMHC on antigen-presenting cells as a co-receptor for TCR-mediated activation of cytotoxic T cells. To characterize this immunologically important interaction, we used monoclonal antibodies (mAbs) specific to either CD8{alpha} or CD8{beta} to probe the mechanism of CD8{alpha}{beta} binding to pMHCI. The YTS156.7 mAb inhibits this interaction and blocks T cell activation. To elucidate the molecular basis for this inhibition, the crystal structure of the CD8{alpha}{beta} immunoglobulin-like ectodomains were determined in complex with mAb YTS156.7 Fab at 2.7 {angstrom} resolution. The YTS156.7 epitope on CD8{beta} was identified and implies that residues in the CDR1 and CDR2-equivalent loops of CD8{beta} are occluded upon binding to class I pMHC. To further characterize the pMHCI/CD8{alpha}{beta} interaction, binding of class I tetramers to CD8{alpha}{beta} on the surface of T cells was assessed in the presence of anti-CD8 mAbs. In contrast to YTS156.7, mAb YTS105.18, which is specific for CD8{alpha}, does not inhibit binding of CD8{alpha}{beta} to class I tetramers, indicating the YTS105.18 epitope is not occluded in the pMHCI/CD8{alpha}{beta} complex. Together, these data indicate a model for the pMHCI/CD8{alpha}{beta} interaction similar to that observed for CD8{alpha}{alpha} in the CD8{alpha}{alpha}/pMHCI complex, but in which CD8{alpha} occupies the lower orientation (membrane proximal to the antigen presenting cell), and CD8{beta} occupies the upper position (membrane distal). The implication of this molecular assembly for the function of CD8{alpha}{beta} in T cell activation is discussed.

  3. Phylogenetic and functional alpha and beta diversity in temperate and tropical tree communities

    Nathan G Swenson; Erikson, David L.; Mi, Xiangcheng; Norman A. Bourg; Forero-Montaña, Jimena; Ge, Xuejun; Howe, Robert; Lake, Jeffrey K.; Liu, Xiaojuan; Ma, Keping; Pei, Nancai; Thompson, Jill; Uriarte, Maria; Wolf, Amy; Wright, S. Joseph


    The study of biodiversity has tended to focus primarily on relatively information poor measures of species diversity. Recently, many studies of local diversity (alpha diversity) have begun to use measures of functional and phylogenetic alpha diversity. Investigations into the phylogenetic and functional dissimilarity (beta diversity) of communities have been far less numerous, but these dissimilarity measures have the potential to infer the mechanisms underlying community assembly and dynamic...

  4. New miniaturized alpha/beta spectrometric system for the surface contamination monitoring and radon personal dosimeter

    The heart of the new miniaturized alpha/beta spectroscopic system is a Smart Card MCA having a 12 bit resolution and a 32 bit memory for each channel with the size of a cheque card. The system consists of a single or up to 12 alpha spectrometers in a battery powered casing with connectors for direct detector/amplifier module plugging. Surface contamination in the order of 1 Bq/cm2 of 239Pu can be measured. (M.D.)

  5. Music genre preference and tempo alter alpha and beta waves in human non-musicians

    Hunter Gentry; Ethan Humphries; Sebastian Pena; Aldijana Mekic; Nicole Hurless; David F Nichols


    This study examined the effects of music genre and tempo on brain activation patterns in 10 nonmusicians.Two genres (rock and jazz) and three tempos (slowed, medium/normal, andquickened) were examined using EEG recording and analyzed through Fast Fourier Transform(FFT) analysis. When participants listened to their preferred genre, an increase in alpha waveamplitude was observed. Alpha waves were not significantly affected by tempo. Beta waveamplitude increased significantly as the tempo incre...

  6. Determination of total alpha and beta activity in water for human consumption by LSC(Liquid Scintillation Counter)

    The Ordinance Brazilian of Ministry of Health (MS 2914/2011) establishes the standards for quality of water intended for human consumption, being limits values of 5.0 Bq/L for gross alpha, and 1.0 Bq/L for gross beta radioactivity. The liquid scintillation spectrometry (LSC) technique has been presented as an alternative to conventional procedure using gas flow proportional counter. The present work shows a review of the methods for determination of gross alpha and gross beta in water by using LSC. Between the factors that influence the accuracy and repeatability of the analytical results we can highlight: thermal preconcentration, type of the acid and calibration standard. A procedure was established and carried out to samples of the National Program of Intercomparison of Radionuclides in Environmental Samples for evaluation of its performance. The gross alpha and gross beta analysis in samples of the public water supplies in the Metropolitan Region of Goiania, state of Goias was carried out. The results are consistent with the guideline values form the Ministry of Health concerning radioactivity. (author)

  7. New miniaturized alpha/beta spectrometric systems for the surface contamination monitoring and radon personal dosimeter

    We report on a new miniaturized alpha/beta spectrometric system. This cheque cart 12 bit SARAD spectra 5011 spectrometric system we can combine with a new developed detector, preamp and forming unit. A very important application of this new measuring system is the alpha nuclidspecific surface contamination monitoring. Especially in old nuclear power station it is very important in the decommissioning process to know the nuclide vector. We report of applications to use this new technology to measure the nuclide vector in old lead cells or construction elements in old nuclear reactors. We measure surface contamination in the order of 1 Bq/cm2 of Pu-239 very easy. A other modification of this cheque cart spectrometer is the radon personal dosimeter. In this case we have integrated on a cheque cart a 8 bit spectrometer, a 1cm2 silicon detector, the signal processing, AD-conversion, data storage and transponder system for the data transfer. Using this transponder system we can also use a local resoluted dosimetry. The main application of this system is the radon dosimetry on workplaces, for instance water works, mines, show caves and other work places with high radon levels. This easy system can replace the passive screening methods and also the nuclear track etch dosimeters. Because the low price and the easy data read out the amortisation of such a electronic system is in the order of two years

  8. Improvement of the in vitro dissolution of praziquantel by complexation with alpha-, beta- and gamma-cyclodextrins.

    Becket, G; Schep, L J; Tan, M Y


    Although praziquantel (PZQ) is the primary drug of choice in the treatment of schistosomiasis, its poor solubility has restricted its delivery via the oral route. In spite of its poor solubility, PZQ is well absorbed across the gastrointestinal tract, but large doses are required to achieve adequate concentrations at the target sites. Improving the solubility would enable the parenteral route to be used, thereby avoiding significant first pass metabolism. The aqueous solubility of PZQ was improved by forming inclusion complexes with alpha-, beta- and gamma-cyclodextrins (CDs). These complexes were assessed and confirmed by solubility analysis, Fourier transform infrared analysis, elemental analysis, differential scanning calorimetry and mass spectrometry. Dissolution of PZQ from the alpha-, beta- and gamma-CD complexes was 2.6-, 5- and 8-fold greater, respectively, than that of the pure drug. However, only the beta-complex had a stability constant in the optimum range for pharmaceutical use, suggesting that the preferred complex for further development would be a water-soluble beta-CD derivative. PMID:10053203

  9. PGC-1alpha and PGC-1beta have both similar and distinct effects on myofiber switching toward an oxidative phenotype

    Mortensen, Ole Hartvig; Frandsen, Lis; Schjerling, Peter; Nishimura, Erica; Grunnet, Niels


    Peroxisome proliferator-activated receptor-gamma coactivator-1alpha and -1beta (PGC-1alpha and PGC-1beta) were overexpressed by adenovirus-mediated gene transfer in cultures of primary rat skeletal muscle cells derived from neonatal myoblasts. Effects on muscle fiber type transition and metabolism...

  10. Treatment of marrow stroma with interferon-alpha restores normal beta 1 integrin-dependent adhesion of chronic myelogenous leukemia hematopoietic progenitors. Role of MIP-1 alpha.

    R Bhatia; McGlave, P B; Verfaillie, C M


    The mechanisms by which interferon-alpha (IFN-alpha) restores normal hematopoiesis in chronic myelogenous leukemia (CML) are not well understood. We have recently demonstrated that IFN-alpha acts directly on CML hematopoietic progenitors to restore their adhesion to marrow stroma by modulating beta 1 integrin receptor function. In the present study we examined the effect of IFN-alpha treatment of marrow stroma on subsequent adhesion of CML progenitors. Stromal layers were preincubated with IF...

  11. A Further Measurement of the beta-Delayed alpha-Particle Emission of 16N

    III, R H F; McDonald, J E; Wilds, E L


    We measured the beta-delayed alpha-particle emission spectrum of 16N with a sensitivity for beta-decay branching ratios of the order of 10-10. The 16N nuclei were produced using the d(15N,16N)p reaction with 70 MeV 15N beams and a deuterium gas target 7.5 cm long at a pressure of 1250 torr. The 16N nuclei were collected (over 10 s) using a thin aluminum foil with an areal density of 180 mu g/cm2 tilted at 7 Deg with respect to the beam. The activity was transferred to the counting area by means of a stepping motor in less than 3 s with the counting carried out over 8 s. The beta-delayed alpha-particles were measured using a time of flight method to achieve a sufficiently low background. Standard calibration sources (148Gd, 241Am, 208,209Po, and 227Ac) as well as alpha-particles and 7Li from the 10B(n,alpha)7Li reaction were used for an accurate energy calibration. The energy resolution of the catcher foil (180-220 keV) was calculated and the time of flight resolution (3-10 nsec) was measured using the beta-de...

  12. Rapid determination of gross alpha and beta activity in contaminated solutions by liquid scintillation spectrometry

    The use of liquid scintillation counting (LSC) as a rapid detection method for emergency situations was studied. The application of the method to a rapid estimation of gross alpha and beta activities in spent decontamination solutions, urine and aerosol filters was tested. The applicable minimum detectable activities were derived by using the standard addition method. (orig.)

  13. Method validation to determine total alpha beta emitters in water samples using LSC

    In this work a method was validated to determine gross alpha and beta emitters in water samples using liquid scintillation counter. 200 ml of water from each sample were evaporated to 20 ml and 8 ml of them were mixed with 12 ml of the suitable cocktail to be measured by liquid scintillation counter Wallac Winspectral 1414. The lower detection limit by this method (LDL) was 0.33 DPM for total alpha emitters and 1.3 DPM for total beta emitters. and the reproducibility limit was (± 2.32 DPM) and (±1.41 DPM) for total alpha and beta emitters respectively, and the repeatability limit was (±2.19 DPM) and (±1.11 DPM) for total alpha and beta emitters respectively. The method is easy and fast because of the simple preparation steps and the large number of samples that can be measured at the same time. In addition, many real samples and standard samples were analyzed by the method and showed accurate results so it was concluded that the method can be used with various water samples. (author)

  14. Gross alpha and gross beta determination in surface and groundwater water by liquid scintillation counting (LSC)

    The present study has used 40 samples of groundwater and surface water collected at four different sites along the period of one year in Brumadinho and Nova Lima, two municipalities in the State of Minas Gerais, Brazil, as part of a more extensive study aiming at determination of the natural radioactivity in the water used for domestic use. These two sites are inside an Environmental Protection Area is located in a region of very intensive iron ore exploration. In addition of mineral resources, the region has a geological characteristic that includes quartzitic conglomerates associated with uranium. Radioactivity levels were determined via liquid scintillation counting (LSC), a fast and high counting efficiency method that can be advantageously employed to determine gross alpha and gross beta activity in liquid samples. Previously to gross alpha and gross beta counting the samples were acidified with concentrated HNO3 in the field. The technique involved a pre-concentration of the sample to obtain a low detection limit. Specific details of the employed methodology are commented. The results showed that concentrations of gross alpha natural activity and gross beta values ranged from less than the detection limit of the equipment (0.03 Bq.L-1) to 0.275 ± 0.05 Bq.L-1 for gross alpha. As regards gross beta, all samples were below the limit of detection. (author)

  15. Fragmentation of alpha- and beta-alanine molecules by ions at Bragg-peak energies

    Bari, S.; Sobocinski, P.; Postma, J.; Alvarado, F.; Hoekstra, R.; Bernigaud, V.; Manil, B.; Rangama, J.; Huber, B.; Schlathoelter, T.


    The interaction of keV He(+), He(2+), and O(5+) ions with isolated alpha and beta isomers of the amino acid alanine was studied by means of high resolution coincidence time-of-flight mass spectrometry. We observed a strong isomer dependence of characteristic fragmentation channels which manifests in

  16. Beta-alanine/alpha-ketoglutarate aminotransferase for 3-hydroxypropionic acid production

    Jessen, Holly Jean; Liao, Hans H; Gort, Steven John; Selifonova, Olga V


    The present disclosure provides novel beta-alanine/alpha ketoglutarate aminotransferase nucleic acid and protein sequences having increased biological activity. Also provided are cells containing such enzymes, as well as methods of their use, for example to produce malonyl semialdehyde and downstream products thereof, such as 3-hydroxypropionic acid and derivatives thereof.

  17. Beta-alanine/alpha-ketoglutarate aminotransferase for 3-hydroxypropionic acid production

    Jessen, Holly Jean (Chanhassen, MN); Liao, Hans H. (Eden Prairie, MN); Gort, Steven John (Apple Valley, MN); Selifonova, Olga V. (Plymouth, MN)


    The present disclosure provides novel beta-alanine/alpha ketoglutarate aminotransferase nucleic acid and protein sequences having increased biological activity. Also provided are cells containing such enzymes, as well as methods of their use, for example to produce malonyl semialdehyde and downstream products thereof, such as 3-hydroxypropionic acid and derivatives thereof.

  18. Alpha and beta particle induced scintillations in liquid and solid neon

    Michniak, R A; McKinsey, D N; Doyle, J M


    Scintillations induced by alpha and beta particles in liquid and solid neon are studied and their light yield measured. Charged particle scintillation in neon is primarily in the extreme ultraviolet (EUV). We detect this EUV light by converting it to blue using a wavelength shifting fluor and detecting the blue light with a photomultiplier tube. It is observed that liquid neon is a somewhat less-efficient scintillator than liquid helium for both alpha and beta radiation while the light yield in solid neon is greater than in liquid helium. Based on our measurements of the relative light yields of liquid and solid neon to liquid helium whose absolute light yield has previously been determined, we find that an alpha source in liquid neon produces up to 5900 photons per MeV while a beta source produces up to 7400 photons per MeV. In solid neon, we find that an alpha particle produces up to 9300 photons per MeV while a beta particle produces up to 17,000 photons per MeV. We observe a significant dependence of the ...

  19. Loss of integrin alpha1beta1 ameliorates Kras-induced lung cancer.

    Macias-Perez, Ines; Borza, Corina; Chen, Xiwu; Yan, Xuexian; Ibanez, Raquel; Mernaugh, Glenda; Matrisian, Lynn M; Zent, Roy; Pozzi, Ambra


    The collagen IV binding receptor integrin alpha1beta1 has been shown to regulate lung cancer due to its proangiogenic properties; however, it is unclear whether this receptor also plays a direct role in promoting primary lung tumors. To investigate this possibility, integrin alpha1-null mice were crossed with KrasLA2 mice that carry an oncogenic mutation of the Kras gene (G12D) and develop spontaneous primary tumors with features of non-small cell lung cancer. We provide evidence that KrasLA2/alpha1-null mice have a decreased incidence of primary lung tumors and longer survival compared with KrasLA2/alpha1 wild-type controls. Tumors from KrasLA2/alpha1-null mice were also smaller, less vascularized, and exhibited reduced cell proliferation and increased apoptosis, as determined by proliferating cell nuclear antigen and terminal deoxynucleotidyl-transferase-mediated dUTP nick-end staining, respectively. Moreover, tumors from the KrasLA2/alpha1-null mice showed diminished extracellular signal-regulated kinase (ERK) but enhanced p38 mitogen-activated protein kinase activation. Primary lung tumor epithelial cells isolated from KrasLA2/alpha1-null mice showed a significant decrease in anchorage-independent colony formation, collagen-mediated cell proliferation, ERK activation, and, most importantly, tumorigenicity when injected into nude mice compared with KrasLA2/alpha1 wild-type tumor cells. These results indicate that loss of the integrin alpha1 subunit decreases the incidence and growth of lung epithelial tumors initiated by oncogenic Kras, suggesting that both Kras and integrin alpha1beta1 cooperate to drive the growth of non-small cell lung cancer in vivo. PMID:18676835

  20. Time course and extent of alpha 1-adrenoceptor density changes in rat heart after beta-adrenoceptor blockade.

    Steinkraus, V.; Nose, M; H. Scholz; Thormählen, K.


    1. It has been suggested that impaired beta-adrenoceptor stimulation is a condition under which the functional role of cardiac alpha 1-adrenoceptors is enhanced. We therefore investigated the extent and time course of changes in alpha 1-adrenoceptor characteristics after chronic treatment with the beta-adrenoceptor blocker propranolol in rat heart. For comparison beta-adrenoceptors were also studied. The mechanism of the changes in adrenoceptor density was investigated with cycloheximide, an ...

  1. Interaction of ibogaine with human alpha3beta4-nicotinic acetylcholine receptors in different conformational states.

    Arias, Hugo R; Rosenberg, Avraham; Targowska-Duda, Katarzyna M; Feuerbach, Dominik; Yuan, Xiao Juan; Jozwiak, Krzysztof; Moaddel, Ruin; Wainer, Irving W


    The interaction of ibogaine and phencyclidine (PCP) with human (h) alpha3beta4-nicotinic acetylcholine receptors (AChRs) in different conformational states was determined by functional and structural approaches including, radioligand binding assays, Ca2+ influx detections, and thermodynamic and kinetics measurements. The results established that (a) ibogaine inhibits (+/-)-epibatidine-induced Ca2+ influx in h(alpha)3beta4 AChRs with approximately 9-fold higher potency than that for PCP, (b) [3H]ibogaine binds to a single site in the h(alpha)3beta4 AChR ion channel with relatively high affinity (Kd = 0.46 +/- 0.06 microM), and ibogaine inhibits [3H]ibogaine binding to the desensitized h(alpha)3beta4 AChR with slightly higher affinity compared to the resting AChR. This is explained by a slower dissociation rate from the desensitized ion channel compared to the resting ion channel, and (c) PCP inhibits [3H]ibogaine binding to the h(alpha)3beta4 AChR, suggesting overlapping sites. The experimental results correlate with the docking simulations suggesting that ibogaine and PCP interact with a binding domain located between the serine (position 6') and valine/phenylalanine (position 13') rings. This interaction is mediated mainly by van der Waals contacts, which is in agreement with the observed enthalpic contribution determined by non-linear chromatography. However, the calculated entropic contribution also indicates local conformational changes. Collectively our data suggest that ibogaine and PCP bind to overlapping sites located between the serine and valine/phenylalanine rings, to finally block the AChR ion channel, and in the case of ibogaine, to probably maintain the AChR in the desensitized state for longer time. PMID:20684041

  2. Divergent evolution of a beta/alpha-barrel subclass: detection of numerous phosphate-binding sites by motif search.

    Bork, P.; Gellerich, J.; Groth, H.; Hooft, R.; Martin, F.


    Study of the most conserved region in many beta/alpha-barrels, the phosphate-binding site, revealed a sequence motif in a few beta/alpha-barrels with known tertiary structure, namely glycolate oxidase (GOX), cytochrome b2 (Cyb2), tryptophan synthase alpha subunit (TrpA), and the indoleglycerolphosphate synthase (TrpC). Database searches identified this motif in numerous other enzyme families: (1) IMP dehydrogenase (IMPDH) and GMP reductase (GuaC); (2) phosphoribosylformimino-5-aminoimidazol c...

  3. Amino acid sequence of the alpha subunit and computer modelling of the alpha and beta subunits of echicetin from the venom of Echis carinatus (saw-scaled viper).

    Polgár, J; Magnenat, E M; Peitsch, M C; Wells, T N; Saqi, M S; Clemetson, K J


    Echicetin, a heterodimeric protein from the venom of Echis carinatus, binds to platelet glycoprotein Ib (GPIb) and so inhibits platelet aggregation or agglutination induced by various platelet agonists acting via GPIb. The amino acid sequence of the beta subunit of echicetin has been reported and found to belong to the recently identified snake venom subclass of the C-type lectin protein family. Echicetin alpha and beta subunits were purified. N-terminal sequence analysis provided direct evidence that the protein purified was echicetin. The paper presents the complete amino acid sequence of the alpha subunit and computer models of the alpha and beta subunits. The sequence of alpha echicetin is highly similar to the alpha and beta chains of various heterodimeric and homodimeric C-type lectins. Neither of the fully reduced and alkylated alpha or beta subunits of echicetin inhibited the platelet agglutination induced by von Willebrand factor-ristocetin or alpha-thrombin. Earlier reports about the inhibitory activity of reduced and alkylated echicetin beta subunit might have been due to partial reduction of the protein. PMID:9163349

  4. Measurement of (222)Rn by absorption in plastic scintillators and alpha/beta pulse shape discrimination.

    Mitev, Krasimir K


    This work demonstrates that common plastic scintillators like BC-400, EJ-200 and SCSF-81 absorb radon and their scintillation pulse decay times are different for alpha- and beta-particles. This allows the application of pulse shape analysis for separation of the pulses of alpha- and beta-particles emitted by the absorbed radon and its progeny. It is shown that after pulse shape discrimination of beta-particles' pulses, the energy resolution of BC-400 and EJ-200 alpha spectra is sufficient to separate the peaks of (222)Rn, (218)Po and (214)Po and allows (222)Rn measurements that are unaffected by the presence of thoron ((220)Rn) in the environment. The alpha energy resolution of SCSF-81 in the experiments degrades due to imperfect collection of the light emitted inside the scintillating fibers. The experiments with plastic scintillation microspheres (PSM) confirm previous findings of other researchers that PSM have alpha-/beta-discrimination properties and show suitability for radon measurements. The diffusion length of radon in BC-400 and EJ-200 is determined. The pilot experiments show that the plastic scintillators are suitable for radon-in-soil-gas measurements. Overall, the results of this work suggest that it is possible to develop a new type of radon measurement instruments which employ absorption in plastic scintillators, pulse-shape discrimination and analysis of the alpha spectra. Such instruments can be very compact and can perform continuous, real-time radon measurements and thoron detection. They can find applications in various fields from radiation protection to earth sciences. PMID:26851823

  5. Detection of Ly$\\beta$ auto-correlations and Ly$\\alpha$-Ly$\\beta$ cross-correlations in BOSS Data Release 9

    Iršič, Vid; Bailey, Stephen; Eisenstein, Daniel J; Font-Ribera, Andreu; Goff, Jean-Marc Le; Lundgren, Britt; McDonald, Patrick; O'Connell, Ross; Palanque-Delabrouille, Nathalie; Petitjean, Patrick; Rich, Jim; Rossi, Graziano; Schneider, Donald P; Sheldon, Erin S; Yèche, Christophe


    The Lyman-$\\beta$ forest refers to a region in the spectra of distant quasars that lies between the rest-frame Lyman-$\\beta$ and Lyman-$\\gamma$ emissions. The forest in this region is dominated by a combination of absorption due to resonant Ly$\\alpha$ and Ly$\\beta$ scattering. When considering the 1D Ly$\\beta$ forest in addition to the 1D Ly$\\alpha$ forest, the full statistical description of the data requires four 1D power spectra: Ly$\\alpha$ and Ly$\\beta$ auto-power spectra and the Ly$\\alpha$-Ly$\\beta$ real and imaginary cross-power spectra. We describe how these can be measured using an optimal quadratic estimator that naturally disentangles Ly$\\alpha$ and Ly$\\beta$ contributions. Using a sample of approximately 60,000 quasar sight-lines from the BOSS Data Release 9, we make the measurement of the one-dimensional power spectrum of fluctuations due to the Ly$\\beta$ resonant scattering. While we have not corrected our measurements for resolution damping of the power and other systematic effects carefully eno...

  6. Molecular cloning and phylogenetic analysis of integrins alpha v beta 1 and alpha v beta 6 of one-humped camel (Camelus dromedarius)

    Du, Junzheng; Larska, Magdalena Larska; Chang, Huiyun;


    Bactrian camels can relatively easily be infected with FMDV, but dromedary camels remain resistant even to high doses of the virus. To understand the different susceptibility between the two camel species from the standpoint of viral receptors, this work reports the sequences of the dromedary camel...... into the Artiodactyla group, together with those of Bactrian camel, pig, sheep, and cattle that are susceptible to FMDV infection. Compared with the Bactrian camel integrins, 4, 10, and 8 amino acid changes were found in the dromedary camel alpha v, beta 1, and beta 6 subunits, respectively. This study...... will be of importance in understanding the differences of integrins as FMDV receptors among dromedary camel and other species. Crown...

  7. Irradiation effect on {alpha}- and {beta}-caseins of milk and Queso Blanco cheese determined by capillary electrophoresis

    Ham, J.S.; Jeong, S.G.; Lee, S.G.; Han, G.S.; Chae, H.S.; Yoo, Y.M.; Kim, D.H. [Animal Food Processing Division, National Institute of Animal Science, Suwon 441-706 (Korea, Republic of); Lee, W.K. [College of Veterinary Medicine, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Jo, C. [Department of Animal Science and Biotechnology, Chungnam National University, Daejeon 305-764 (Korea, Republic of)], E-mail:


    Milk and Queso Blanco cheese were exposed to irradiation with doses of 1, 2, 3, 5, and 10 kGy to investigate the irradiation effect on {alpha}- and {beta}-casein using a capillary electrophoresis. {alpha}{sub S1}-Casein to total protein ratio in raw milk was decreased from 19.63% to 8.64% by 10 kGy of gamma irradiation. The ratio of {alpha}{sub S1}- to {alpha}{sub S0}-casein was also decreased from 1.38 to 0.53, which showed {alpha}{sub S1}-casein is more susceptible to gamma irradiation than {alpha}{sub S0}-casein. Similarly, {alpha}{sub S1}-casein to total protein ratio in Queso Blanco cheese was decreased from 17.48% to 7.82% and the ratio of {alpha}{sub S1}- to {alpha}{sub S0}-casein was decreased from 1.16 to 0.43 by 10 kGy of gamma irradiation. Dose-dependent reduction of {beta}{sub A1}-casein was also found. {beta}{sub A1}-Casein to total protein ratios in raw milk and Queso Blanco cheese were decreased from 22.00% to 14.16% and from 21.96% to 13.89% after 10 kGy, respectively. The ratios of {beta}{sub A1}- to {beta}{sub A2}-casein were from 1.10 to 0.64 and 0.93 to 0.57 in milk and Queso Blanco cheese, respectively. However, {alpha}{sub S0}-, {beta}{sub B}-, and {beta}{sub A3}-casein increased by irradiation at 10 kGy. The results suggest that {alpha}{sub S1}-casein and {beta}{sub A1}-casein were more susceptible to gamma irradiation, and may be related to the reduction of milk allergenicity caused by gamma irradiation.

  8. PET imaging of alpha(v)beta(3) integrin expression in tumours with Ga-68-labelled mono-, di- and tetrameric RGD peptides

    Dijkgraaf, Ingrid; Yim, Cheng-Bin; Franssen, Gerben M.; Schuit, Robert C.; Luurtsema, Gert; Liu, Shuang; Oyen, Wim J. G.; Boerman, Otto C.


    Due to the restricted expression of alpha(v)beta(3) in tumours, alpha(v)beta(3) is considered a suitable receptor for tumour targeting. In this study the alpha(v)beta(3)-binding characteristics of Ga-68-labelled monomeric, dimeric and tetrameric RGD peptides were determined and compared with their I

  9. Interleukin-1beta and tumor necrosis factor-alpha are expressed by different subsets of microglia and macrophages after ischemic stroke in mice

    Clausen, Bettina Hjelm; Lambertsen, Kate Lykke; Babcock, Alicia;


    BACKGROUND: Interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) are expressed by microglia and infiltrating macrophages following ischemic stroke. Whereas IL-1beta is primarily neurotoxic in ischemic stroke, TNF-alpha may have neurotoxic and/or neuroprotective effects. We inv...


    HOLDEN, H.E.


    In his review of radionuclides for dating purposes, Roth noted that there were a large number of nuclides, normally considered ''stable'' but which are radioactive with a very long half-life. Roth suggested that I review the data on the half-life values of these long-lived nuclides for the 2001 Atomic Weights Commission meeting in Brisbane. I provided a report, BNL-NCS-68377, to fulfill Roth's request. Peiser has now made a similar suggestion that I review these data for our next Commission meeting in Ottawa for their possible inclusion in our Tables. These half-life values for long-lived nuclides include those due to various decay modes, {alpha}-decay, {beta}-decay, electron capture decay, {beta}{beta}-decay, proton decay and spontaneous fission decay. This data review (post Brisbane) provides an update to the recommendation of the 2001 review.

  11. Effects of microstructural parameters and back stress on damage mechanisms in {alpha}/{beta} titanium alloys

    Helbert, A.L.; Feaugas, X.; Clavel, M. [Univ. de Technologie de Compiegne (France)


    Damage initiation and kinetics in four {alpha}/{beta} titanium alloys have been experimentally and numerically investigated. Efforts were focused on triaxiality, {chi} = {Sigma}{sub m}/{Sigma}{sub eq} and internal stresses effects. The study of void nucleation has provided nucleation criteria corresponding to voids at the {alpha}/{beta} interface. This macroscopic nucleation criterion, written as {Sigma}{sub m} = f({var_epsilon}{sub peq}), was explained with the help of microscopic observations. Microscopic parameters such as plastic strain in the {alpha}-phase or local hydrostatic stress {sigma}{sub m}{sup loc} at the {alpha}/{beta} interface have been linked to the damage initiation. Also, the influence of the different heterogeneity levels on the macroscopic nucleation criterion was demonstrated. It has also been shown that internal stresses increased both nucleation and growth kinetics. Damage mechanisms are well described by a Gurson-Tvergaard model modified to take into account internal stresses. In particular, the existence of a material physical property, f{sub c} (void volume fraction at fracture) was shown.

  12. Inhibitory effects of Turkish folk remedies on inflammatory cytokines: interleukin-1alpha, interleukin-1beta and tumor necrosis factor alpha.

    Yeşilada, E; Ustün, O; Sezik, E; Takaishi, Y; Ono, Y; Honda, G


    In this study, in vitro inhibitory effects of 55 extracts or fractions obtained from 10 plant species on interleukin-1 (IL-1alpha, IL-1beta) and tumor necrosis factor (TNF-alpha) biosynthesis were studied. The following plant materials from Turkish folk medicine for the treatment of various diseases which are thought to be inflammatory in nature e.g. rheumatism, fever, infections, edemas or related inflammatory diseases were selected as the subject of this study: Cistus laurifolius leaves, Clematis flammna flowering herbs, Crataegus orientalis roots, Daphne oleoides ssp. oleoides whole plant, Ecbalium elaterium roots, Rosa canina roots, Rubus discolor roots, Rubus hirtus roots, Sambucus ebulus flowers and leaves, Sambucus nigra flowers and leaves. All plants showed inhibitory activity against at least one of these models in various percentages depending upon the concentration, thus supporting the folkloric utilization. Daphne oleoides was found to be the most active plant against the test models. PMID:9324006

  13. Evaluation of different parameters affecting the liquid scintillation spectrometry measurement of gross alpha and beta index in water samples

    Liquid scintillation spectrometry is a fast competitive technique for the simultaneous evaluation of gross alpha and beta indexes. However, the implementation of this technique should not be considered as straightforward, and the pre-concentration methods to decrease the detection limit together with quenching and alpha, and beta crossover corrections should be carefully chosen according to the needs of the laboratory. Both aspects are being approached in this work as to find an easy and robust method for alpha/beta measurement in water samples, taking into account the quenching and alpha/beta crossover interferences effects. Results showed that most of the pre-concentration methods increased the quenching in the measurement, although HNO3 0.05 M points to be the best solution for pre-concentration and re-dissolution of the sample as converges into low quenching and maximum recovery. Subsequently, in the measurement of water samples with different conductivities, the analysis of the raw counts to obtain gross alpha and beta indexes was carried out using different approaches to implement quenching and interference corrections. If quenching and salt content in the sample are relatively low, interference and quenching-efficiency corrections do not improve the accuracy of the results within the usual precision assumed for a result of gross alpha and beta index (25%). Special attention must be paid when corrections are applied to high quenched or saline samples and when alpha and beta activities values are different in several orders of magnitude. - Highlights: → Developed method for simultaneously quantifying gross alpha and gross beta indexes based on LSC was as accurate and precise as the results obtained from methods based on gas proportional counting and ZnS alpha counting. → Alpha/beta crossover and/or quenching corrections were applied and the results obtained did not improve accuracy within 25% dispersion, a widespread acceptance limit for gross alpha and

  14. Evaluation of different parameters affecting the liquid scintillation spectrometry measurement of gross alpha and beta index in water samples

    Palomo, M. [Unitat de Radioquimica Ambiental i Sanitaria, Universitat Rovira i Virgili, Tarragona (Spain); Villa, M. [Centro de Investigacion, Tecnologia e Innovacion. Servicio Radioisotopos. Universidad de Sevilla (Spain); Casacuberta, N. [Institut de Ciencia i Tecnologia Ambientals-Departament de Fisica, Universitat Autonoma de Barcelona. Spain (Spain); Penalver, A.; Borrull, F. [Unitat de Radioquimica Ambiental i Sanitaria, Universitat Rovira i Virgili, Tarragona (Spain); Aguilar, C., E-mail: [Unitat de Radioquimica Ambiental i Sanitaria, Universitat Rovira i Virgili, Tarragona (Spain)


    Liquid scintillation spectrometry is a fast competitive technique for the simultaneous evaluation of gross alpha and beta indexes. However, the implementation of this technique should not be considered as straightforward, and the pre-concentration methods to decrease the detection limit together with quenching and alpha, and beta crossover corrections should be carefully chosen according to the needs of the laboratory. Both aspects are being approached in this work as to find an easy and robust method for alpha/beta measurement in water samples, taking into account the quenching and alpha/beta crossover interferences effects. Results showed that most of the pre-concentration methods increased the quenching in the measurement, although HNO{sub 3} 0.05 M points to be the best solution for pre-concentration and re-dissolution of the sample as converges into low quenching and maximum recovery. Subsequently, in the measurement of water samples with different conductivities, the analysis of the raw counts to obtain gross alpha and beta indexes was carried out using different approaches to implement quenching and interference corrections. If quenching and salt content in the sample are relatively low, interference and quenching-efficiency corrections do not improve the accuracy of the results within the usual precision assumed for a result of gross alpha and beta index (25%). Special attention must be paid when corrections are applied to high quenched or saline samples and when alpha and beta activities values are different in several orders of magnitude. - Highlights: > Developed method for simultaneously quantifying gross alpha and gross beta indexes based on LSC was as accurate and precise as the results obtained from methods based on gas proportional counting and ZnS alpha counting. > Alpha/beta crossover and/or quenching corrections were applied and the results obtained did not improve accuracy within 25% dispersion, a widespread acceptance limit for gross alpha and

  15. The androgen 5alpha-dihydrotestosterone and its metabolite 5alpha-androstan-3beta, 17beta-diol inhibit the hypothalamo-pituitary-adrenal response to stress by acting through estrogen receptor beta-expressing neurons in the hypothalamus.

    Lund, Trent D; Hinds, Laura R; Handa, Robert J


    Estrogen receptor beta (ERbeta) and androgen receptor (AR) are found in high levels within populations of neurons in the hypothalamus. To determine whether AR or ERbeta plays a role in regulating hypothalamo-pituitary-adrenal (HPA) axis function by direct action on these neurons, we examined the effects of central implants of 17beta-estradiol (E2), 5alpha-dihydrotestosterone (DHT), the DHT metabolite 5alpha-androstan-3beta, 17beta-diol (3beta-diol), and several ER subtype-selective agonists on the corticosterone and adrenocorticotropin (ACTH) response to immobilization stress. In addition, activation of neurons in the paraventricular nucleus (PVN) was monitored by examining c-fos mRNA expression. Pellets containing these compounds were stereotaxically implanted near the PVN of gonadectomized male rats. Seven days later, animals were killed directly from their home cage (nonstressed) or were restrained for 30 min (stressed) before they were killed. Compared with controls, E2 and the ERalpha-selective agonists moxestrol and propyl-pyrazole-triol significantly increased the stress induced release of corticosterone and ACTH. In contrast, central administration of DHT, 3beta-diol, and the ERbeta-selective compound diarylpropionitrile significantly decreased the corticosterone and ACTH response to immobilization. Cotreatment with the ER antagonist tamoxifen completely blocked the effects of 3beta-diol and partially blocked the effect of DHT, whereas the AR antagonist flutamide had no effect. Moreover, DHT, 3beta-diol, and diarylpropionitrile treatment significantly decreased restraint-induced c-fos mRNA expression in the PVN. Together, these studies indicate that the inhibitory effects of DHT on HPA axis activity may be in part mediated via its conversion to 3beta-diol and subsequent binding to ERbeta. PMID:16452668

  16. Mechanical alloying of Fe-Si and milling of {alpha}- and {beta}-FeSi{sub 2} bulk phases

    Dezsi, I., E-mail: dezsi@kfki.rmki.h [KFKI Research Institute for Particle and Nuclear Physics, H-1525 Budapest, 114 P.O. Box 49 (Hungary); Fetzer, Cs. [KFKI Research Institute for Particle and Nuclear Physics, H-1525 Budapest, 114 P.O. Box 49 (Hungary); Bujdoso, L. [MTA Research Institute for Solid State Physics and Optics, H-1525 Budapest, 114 P.O. Box 49 (Hungary); Broetz, J.; Balogh, A.G. [Institute of Materials Science, Technische Universitaet Darmstadt, 64287 Darmstadt (Germany)


    Research highlights: Mechanical alloying of Fe-Si and milling of {alpha}- and {beta}-FeSi{sub 2} bulk phases deals with the formation of various Fe-Si phases applying milling technique. Systematic studies were performed on the relative intensities on the different structures depending on the milling periods. - Abstract: Iron disilicide synthesis by mechanical alloying was performed. {epsilon}-FeSi, {alpha}-Fe{sub 1-x}Si{sub 2}, amorphous FeSi{sub 2} were formed with relative intensities depending on the milling period. {beta}-FeSi{sub 2} phase was formed after annealing the gridded powder at the temperature where this phase is stable. Moessbauer spectroscopy and X-ray diffraction methods were applied to determine the different phases formed. The morphology of the resulting particles was observed by high resolution scanning electron microscopy. The effect of the milling on bulk iron-silicide samples was and studied chemical effects of the ball milling on Fe-Si{sub 2} systems have been studied.

  17. Renal and cardiac function during alpha1-beta-blockade in congestive heart failure

    Heitmann, M; Davidsen, U; Stokholm, K H;


    The kidney and the neurohormonal systems are essential in the pathogenesis of congestive heart failure (CHF) and the physiologic response. Routine treatment of moderate to severe CHF consists of diuretics, angiotensin-converting enzyme (ACE) inhibition and beta-blockade. The need for control of...... renal function during initiation of ACE-inhibition in patients with CHF is well known. The aim of this study was to investigate whether supplementation by a combined alpha1-beta-blockade to diuretics and ACE-inhibition might improve cardiac function without reducing renal function....

  18. Inhibition of mutagenicity in Salmonella typhimurium and skin tumor initiating and tumor promoting activities in SENCAR mice by glycyrrhetinic acid: comparison of 18 alpha- and 18 beta-stereoisomers.

    Wang, Z Y; Agarwal, R; Zhou, Z C; Bickers, D R; Mukhtar, H


    Licorice has been used as medicine and as sweetening agent in food products. The major water-soluble constituent of licorice is glycyrrhizin (GL), an oleanane triterpenoide, which is known to be partly hydrolyzed by glucuronidase to its aglycone glycyrrhetinic acid (GA) which exists in 18 alpha (alpha-GA) and 18 beta (beta-GA) stereoisomeric forms. In this study alpha-GA and beta-GA were found to inhibit the mutagenicity of benzo[a]pyrene (B[a]P), 2-aminofluorene and aflatoxin B1 in Salmonella typhimurium TA98 and TA100. beta-GA was more effective than alpha-GA as an antimutagen. In the two-stage skin tumorigenesis protocol using 7,12-dimethylbenz[a]anthracene (DMBA) as the tumor initiating agent followed by twice weekly applications of 12-O-tetradecanoylphorbol-13-acetate as tumor promoter, pretreatment of SENCAR mice with alpha-GA or beta-GA resulted in significant protection against tumor initiation as well as tumor promotion. As an anti-tumor initiating agent, beta-GA was found to be more effective than alpha-GA. Similarly, topical application of beta-GA was found to be more effective than alpha-GA in inhibiting the binding of both [3H]B[a]P and [3H]DMBA to epidermal DNA. However, as an anti-tumor promoter, alpha-GA and beta-GA showed comparable effects. Our results suggest that both alpha-GA and beta-GA possess substantial anti-skin tumor initiating and anti-skin tumor promoting activities. PMID:1899808

  19. alpha4beta2 nicotinic acetylcholine receptors on dopaminergic neurons mediate nicotine reward and anxiety relief

    McGranahan, Tresa M.; Patzlaff, Natalie E.; Grady, Sharon R; Heinemann, Stephen F.; Booker, T.K.


    Nicotine is the primary psychoactive substance in tobacco and it exerts its effects by interaction with various subtypes of nicotinic acetylcholine receptors (nAChRs) in the brain. One of the major subtypes expressed in brain, the alpha4beta2-nAChR, endogenously modulates neuronal excitability and thereby, modifies certain normal, as well as nicotine-induced, behaviors. Although alpha4-containing nAChRs are widely expressed across the brain, a major focus has been on their roles within midbra...

  20. The cognitive effects of trauma: reversal of alpha function and the formation of a beta screen.

    Brown, Lawrence J


    Following a brief review of Freud's writings on trauma, the author discusses relevant theories of Bion, and in particular the concepts of the alpha function and the beta screen. A clinical example is presented in which the patient's relatively recent trauma in adulthood had become fused with prior related experiences, leading to a propensity for repeated enactments in analysis and a failure to learn from experience. Drawing on the analyst's alpha function, the patient was gradually able to use mentalization to transform her rigidly structured traumatic organization. The author highlights the roles of dreams/dream associations and of screen memories in the patient's analysis. PMID:15889686

  1. cDNA clone for the alpha-chain of human beta-hexosaminidase: deficiency of alpha-chain mRNA in Ashkenazi Tay-Sachs fibroblasts.

    Myerowitz, R; Proia, R L


    We have isolated a cDNA clone containing sequences complementary to mRNA encoding the alpha-chain of the lysosomal enzyme beta-hexosaminidase. RNA from a human lung fibroblast strain, IMR90, was enriched for beta-hexosaminidase messenger by polysome immunoselection with antiserum against beta-hexosaminidase A. This preparation was used to construct cDNA recombinant plasmids by the Okayama-Berg vector primer procedure. After transformation of Escherichia coli, 385 ampicillin-resistant colonies...

  2. LRAD, semiconductor, and other radiation detectors applied to environmental monitoring for alpha and beta contamination

    The very short range of alpha particles in air (typically 2 to 3 cm) has severely limited the use of traditional alpha monitors for detecting and identifying small amounts of alpha-producing contamination in soil, water, and other materials. Monitors based on the traditional alpha detector technology are often hard pressed to meet continually increasing sensitivity requirements. The long-range alpha detector (LRAD) avoids the distance restriction by detecting the ions produced by the interaction of alpha particles with air, rather than the alpha particles directly. The ions are swept into an ion detector either by a moving air current (generated by a fan) or a weak electric field. The LRAD is limited by the distance the ions can travel in the ∼5-s ion lifetime (1 to 100 m), rather than by the several-centimeter range of the alpha particles. The LRAD can be used to perform sensitive (less than 10 disintegrations per minute per 100 cm2) field scans of large surface areas (ranging from hundreds of square meters of concrete floor to thousands of square meters of soil). Because the 'active' element in a LRAD is a solid-metal ion collection plate, the detector is relatively inexpensive, easy to service, and quite rugged. However, the LRAD cannot supply any spectroscopic information to help identify the contaminant. Semiconductor, ionization chamber, and other types of particle detector can generate clean spectra from small samples of material and can identify trace amounts of surface contamination. Furthermore, these detectors are rugged enough to use routinely in a mobile laboratory for isotope identification of 'hot spots' located by the LRAD system. The combination of the LRAD with either an alpha spectrometer or a mobile laboratory with other particle detectors has applications for field beta-particle monitoring (such as would result from tritium contamination) as well as alpha particle detection. (author)

  3. The effect of an ionic detergent on the natively unfolded beta-dystroglycan ectodomain and on its interaction with alpha-dystroglycan.

    Bozzi, Manuela; Di Stasio, Enrico; Cicero, Daniel O; Giardina, Bruno; Paci, Maurizio; Brancaccio, Andrea


    Dystroglycan (DG) is an adhesion complex, expressed in a wide variety of tissues, formed by an extracellular and a transmembrane subunit, alpha-DG and beta-DG, respectively, interacting noncovalently. Recently, we have shown that the recombinant ectodomain of beta-DG, beta-DG(654-750), behaves as a natively unfolded protein, as it is able to bind the C-terminal domain of alpha-DG, while not displaying a defined structural organization. We monitored the effect of a commonly used denaturing agent, the anionic detergent sodium dodecylsulphate (SDS), on beta-DG(654-750) using a number of biophysical techniques. Very low concentrations of SDS (SDS does not induce any evident conformational rearrangement within the ectodomain of beta-DG. Its first 70 amino acids, which show a lower degree of mobility, interact with the detergent, but this does not change the amount of secondary structure, whereas the highly flexible and mobile C-terminal region of beta-DG(654-750) remains largely unaffected, even at a very high SDS concentration (up to 50 mM). Our data indicate that SDS can be used as a useful tool for investigating natively unfolded proteins, and confirm that the beta-DG ectodomain is an interesting model system. PMID:15295116

  4. The Atlantic Salmon MHC class II alpha and beta promoters are active in mammalian cell lines.

    Vestrheim, O; Lundin, M; Syed, M


    The major histocompatibility complex class II (MHCII) genes are only constitutively expressed in certain immune response cells such as B cells, macrophages, dendritic cells and other antigen presenting cells. This cell specific expression pattern and the presence of conserved regions such as the X-, X2-, Y-, and W-boxes make the MHCII promoters especially interesting as vector constructs. We tested whether the Atlantic salmon (Salmo salar L.) MHCII promoters can function in cell lines from other organisms. We found that the salmon MHCII alpha and MHCII beta promoters could drive expression of a LacZ reporter gene in adherent lymphoblast cell lines from dog (DH82) and rabbit (HybL-L). This paper shows that the promoters of Atlantic salmon MHCII alpha and beta genes can function in mammalian cell lines. PMID:17934904

  5. Improvement and automatization of a proportional alpha-beta counting system - FAG

    An alpha and beta counting system - FAG*, for planchette samples is operated at the Health Physics department's laboratory of the NRCN. The original operation mode of the system was based on manual tasks handled by the FHT1 100 electronics. An option for a basic computer keyboard operation was available too. A computer with an appropriate I/O card was connected to the system and a new operating program was developed which enables full automatic control of the various components. The program includes activity calculations and statistical checks as well as data management. A bar-code laser system for sample number reading was integrated into the Alpha-Beta automatic counting system. The sample identification by means of an attached bar-code label enables unmistakable and reliable attribution of results to the counted sample. authors)

  6. Plant diversity predicts beta but not alpha diversity of soil microbes across grasslands worldwide

    Prober, Suzanne M.; Leff, Jonathan W.; Bates, Scott T.; Borer, Elizabeth T.; Firn, Jennifer; Harpole, W. Stanley; Lind, Eric M.; Seabloom, Eric W.; Adler, Peter B.; Bakker, Jonathan D.; Cleland, Elsa E.; DeCrappeo, Nicole; DeLorenze, Elizabeth; Hagenah, Nicole; Hautier, Yann; Hofmockel, Kirsten S.; Kirkman, Kevin P.; Knops, Johannes M. H.; La Pierre, Kimberly J.; MacDougall, Andrew S.; McCulley, Rebecca L.; Mitchell, Charles E.; Risch, Anita C.; Schuetz, Martin; Stevens, Carly J.; Williams, Ryan J.; Fierer, Noah


    Aboveground–belowground interactions exert critical controls on the composition and function of terrestrial ecosystems, yet the fundamental relationships between plant diversity and soil microbial diversity remain elusive. Theory predicts predominantly positive associations but tests within single sites have shown variable relationships, and associations between plant and microbial diversity across broad spatial scales remain largely unexplored. We compared the diversity of plant, bacterial, archaeal and fungal communities in one hundred and forty-five 1 m2 plots across 25 temperate grassland sites from four continents. Across sites, the plant alpha diversity patterns were poorly related to those observed for any soil microbial group. However, plant beta diversity (compositional dissimilarity between sites) was significantly correlated with the beta diversity of bacterial and fungal communities, even after controlling for environmental factors. Thus, across a global range of temperate grasslands, plant diversity can predict patterns in the composition of soil microbial communities, but not patterns in alpha diversity.

  7. Plant diversity predicts beta but not alpha diversity of soil microbes across grasslands worldwide.

    Prober, Suzanne M; Leff, Jonathan W; Bates, Scott T; Borer, Elizabeth T; Firn, Jennifer; Harpole, W Stanley; Lind, Eric M; Seabloom, Eric W; Adler, Peter B; Bakker, Jonathan D; Cleland, Elsa E; DeCrappeo, Nicole M; DeLorenze, Elizabeth; Hagenah, Nicole; Hautier, Yann; Hofmockel, Kirsten S; Kirkman, Kevin P; Knops, Johannes M H; La Pierre, Kimberly J; MacDougall, Andrew S; McCulley, Rebecca L; Mitchell, Charles E; Risch, Anita C; Schuetz, Martin; Stevens, Carly J; Williams, Ryan J; Fierer, Noah


    Aboveground-belowground interactions exert critical controls on the composition and function of terrestrial ecosystems, yet the fundamental relationships between plant diversity and soil microbial diversity remain elusive. Theory predicts predominantly positive associations but tests within single sites have shown variable relationships, and associations between plant and microbial diversity across broad spatial scales remain largely unexplored. We compared the diversity of plant, bacterial, archaeal and fungal communities in one hundred and forty-five 1 m(2) plots across 25 temperate grassland sites from four continents. Across sites, the plant alpha diversity patterns were poorly related to those observed for any soil microbial group. However, plant beta diversity (compositional dissimilarity between sites) was significantly correlated with the beta diversity of bacterial and fungal communities, even after controlling for environmental factors. Thus, across a global range of temperate grasslands, plant diversity can predict patterns in the composition of soil microbial communities, but not patterns in alpha diversity. PMID:25430889

  8. A measurement system for alpha and beta surface emission rate using MWPC

    Lin, Ye; Fang, Fang; Ren, Jia-Fu; He, Lin-Feng; Tang, Fang-Dong; Xu, Yi-He; Ding, Wei-Cheng


    We have developed a large area multi-wire proportional counter (MWPC) as a standard for the measurement of alpha and beta surface emission rate at the Shanghai Institute of Measurement and Testing Technology (SIMT). To shorten the preparation time for chamber gas refilling, a self-designed gas control unit was adopted. Various characteristics of the system have been studied. The uncertainties were analysed. Three certified alpha plane sources (Am-241) and six certified beta plane sources (Tl-204 and Sr-90/Y-90) were measured by this system. The results show excellent agreement with the surface emission rate reported by the National Institute of Measuring, China (NIM) that En values of all measured sources are within ±1. Supported by National Natural Science Foundation of China (41204133)

  9. A prototype low-background multiwire proportional chamber for measuring alphas and low-energy betas

    Ahmed, Z; Bunker, R; Golwala, S R; Grant, D R; Kos, M; Nelson, R H; Rider, A; Schnee, R W; Sotolongo, D; Wang, B; Zahn, A


    A prototype low-background multiwire proportional chamber (MWPC) was developed to demonstrate the feasibility of constructing a radiopure MWPC to assay materials for alpha- and beta-emitting surface contaminants for future rare-event-search experiments, as well as other scientific fields. We discuss the design features and assembly techniques used to achieve the energy and position resolution for for efficient rejection of both intrinsic and external backgrounds. Results from a test setup using a 5.89\\,keV x-ray source indicate excellent operational stability and a near-ideal energy resolution of 15.8% FWHM. This detector technology promises significant advances in both alpha and low-energy (<200 keV) beta screening.

  10. Hot working analysis of a CuZn40Pb2 brass on the monophasic (beta) and intercritical (alpha plus beta) regions

    L. Suarez; Rodríguez Calvillo, Pablo; Cabrera Marrero, José M.; Martinez Romay, A; Majuelos Mallorquin, D


    The high temperature deformation behavior of a Cu4OZn2Pb brass was studied by means of compression and tensile tests in the beta monophasic and alpha/beta biphasic regions. The ductility evaluated in terms of elongation and area reduction allowed to distinguish three regions: one 13 monophasic region (above 720 degrees C), and two alpha/beta biphasic regions, between 720 degrees C and 600 degrees C, and below 600 degrees C. The fracture appearance was evolving from a ductile type, with dimple...

  11. Antimicrobial activity of basic cholane derivatives. X. Synthesis of 3 alpha- and 3 beta-amino-5 beta-cholan-24-oic acids.

    Bellini, A M; Mencini, E; Quaglio, M P; Guarneri, M; Fini, A


    A simple and convenient route to 3 alpha- and 3 beta-amino-5 beta-cholan-24-oic acids was developed via Leuckart-Wallach amination reduction and subsequent acid hydrolysis. Two epimeric formylamino derivatives were produced (alpha and beta), approximately in a 1:1 ratio, as determined by 13C nuclear magnetic resonance spectroscopy. The two isomers were separated by making use of their different solubilities in ethyl ether. The absolute configuration of the two amino acids was assigned by comparison with authentic reference samples. PMID:1780957

  12. Beta-alpha correlation in the decay of 20Na

    The β-α angular correlation has been measured in the allowed positron decay of 20Na to the 7.42 MeV state of 20Ne. The correlation is of the form 1+a(mean)cos(theta) + p(mean)cos2(theta). p(mean)=-0.003+-0.005 is found in reasonable agreement with expectations based on the conserved vector current theory. (Auth.)

  13. PNNL OS3300 Alpha/Beta Monitoring System Software and Hardware Operations Manual, Revision 0

    This Pacific Northwest National Laboratory (PNNL) OS3300 Alpha/Beta Monitoring System Software and Hardware Operations Manual describes how to install and operate the software and hardware on a personal computer in conjunction with the EG and G Berthold LB150D continuous air monitor. Included are operational details for the software functions, how to read and use the drop-down menus, how to understand readings and calculations, and how to access the database tables

  14. PNNL OS3300 Alpha/Beta Monitoring System Software and Hardware Operations Manual, Revision 0

    Barnett, J. M.; Duchsherer, Cheryl J.; Sisk, Daniel R.; Carter, Gregory L.; Douglas, David D.; Carrell, Dorothy M.


    This Pacific Northwest National Laboratory (PNNL) OS3300 Alpha/Beta Monitoring System Software and Hardware Operations Manual describes how to install and operate the software and hardware on a personal computer in conjunction with the EG&G Berthold LB150D continuous air monitor. Included are operational details for the software functions, how to read and use the drop-down menus, how to understand readings and calculations, and how to access the database tables.

  15. Modulation of transmission in rat sympathetic ganglia by activation of presynaptic alpha- and beta-adrenoceptors.

    Medgett, I.C.


    1 Conditions under which transmission in rat isolated superior cervical ganglia may be affected by activation of presynaptic alpha- and beta-adrenoceptors have been investigated by means of an extracellular recording method. 2 Clonidine caused a small hyperpolarization of the ganglia (mean EC50 approximately 2 nM) in unstimulated preparations; with continuous preganglionic stimulation at 0.2 Hz, clonidine markedly decreased the height of the compound action potential (mean EC50 approximately ...

  16. Density functional theory study of electroreductive hydrocoupling of alpha,beta-unsaturated carbonyl compounds.

    Kise, Naoki


    [reaction: see text] The electroreductive hydrocoupling of methyl cinnamate, methyl crotonate, cumarin, and benzalacetone was studied by DFT (B3LYP/6-311++ G**) calculations. The computational outcomes for the transition states in the hydrocoupling of anion radicals generated by a one-electron transfer to the alpha,beta-unsaturated carbonyl compounds well agree with the diastereoselectivities in the experimental results previously reported. PMID:17109548

  17. Different roles of alpha and beta band oscillations in sensorimotor gating

    Verena Nadine Buchholz


    Full Text Available Alpha (8-12Hz and beta band (18-30Hz oscillations have been implicated in sensory anticipation and motor preparation. Here, using magneto-encephalography, we tested whether they have distinct functional roles in a saccade task that induces a remapping between sensory and motor reference frames. With a crossed hands posture, subjects had to saccade as fast and accurate as possible toward a tactile stimulus delivered to one of two non-visible index fingers, located to the left or right of gaze. Previous studies have shown that this task, in which the somatotopic stimulus must be remapped to activate oculomotor system in the opposing hemisphere, is occasionally preceded by intrahemispheric remapping, driving a premature saccade into the wrong direction. To test whether the brain could anticipate the remapping, we provided auditory predictive cues (80% validity, which indicated which finger is most likely to be stimulated. Both frequency bands showed different lateralization profiles at central versus posterior sensors, indicating anticipation of somatosensory and oculomotor processing. Furthermore, beta band power in somatosensory cortex correlated positively with saccade reaction time (SRT, with correlation values that were significantly higher with contralateral versus ipsilateral activation. In contrast, alpha band power in parietal cortex correlated negatively with SRT, with correlation values that were significantly more negative with ipsilateral than contralateral activation. These results suggest distinct functional roles of beta and alpha band activity: 1 somatosensory gating by beta oscillations, increasing excitability in contralateral somatosensory cortex (positive correlation and 2 oculomotor gating by posterior alpha oscillations, inhibiting gaze-centered oculomotor regions involved in generating the saccade to the wrong direction (negative correlation. Our results show that low frequency rhythms gate upcoming sensorimotor

  18. Induction of nuclear factor-kappaB and its downstream genes by TNF-alpha and IL-1beta has a pro-apoptotic role in pancreatic beta cells

    Ortis, F; Pirot, P; Naamane, N; Kreins, A Y; Rasschaert, J; Moore, F; Théâtre, E; Verhaeghe, C; Magnusson, N E; Chariot, A; Orntoft, T F; Eizirik, D L


    AIMS/HYPOTHESIS: IL-1beta and TNF-alpha contribute to pancreatic beta cell death in type 1 diabetes. Both cytokines activate the transcription factor nuclear factor-kappaB (NF-kappaB), but recent observations suggest that NF-kappaB blockade prevents IL-1beta + IFN-gamma- but not TNF-alpha + IFN......: Blocking NF-kappaB activation protected beta cells against IL-1beta + IFNgamma- or TNFalpha + IFNgamma-induced apoptosis. Blocking de novo protein synthesis did not increase TNF-alpha- or IL-1beta-induced beta cell death, in line with the observations that cytokines induced the expression of the anti...

  19. Plasmin-induced migration requires signaling through protease-activated receptor 1 and integrin alpha(9)beta(1).

    Majumdar, Mousumi; Tarui, Takehiko; Shi, Biao; Akakura, Nobuaki; Ruf, Wolfram; Takada, Yoshikazu


    Plasmin is a major extracellular protease that elicits intracellular signals to mediate platelet aggregation, chemotaxis of peripheral blood monocytes, and release of arachidonate and leukotriene from several cell types in a G protein-dependent manner. Angiostatin, a fragment of plasmin(ogen), is a ligand and an antagonist for integrin alpha(9)beta(1). Here we report that plasmin specifically interacts with alpha(9)beta(1) and that plasmin induces of cells expressing migration recombinant alpha(9)beta(1) (alpha(9)-Chinese hamster ovary (CHO) cells). Migration was dependent on an interaction of the kringle domains of plasmin with alpha(9)beta(1) as well as the catalytic activity of plasmin. Angiostatin, representing the kringle domains of plasmin, alone did not induce the migration of alpha(9)-CHO cells, but simultaneous activation of the G protein-coupled protease-activated receptor (PAR)-1 with an agonist peptide induced the migration on angiostatin, whereas PAR-2 or PAR-4 agonist peptides were without effect. Furthermore, a small chemical inhibitor of PAR-1 (RWJ 58259) and a palmitoylated PAR-1-blocking peptide inhibited plasmin-induced migration of alpha(9)-CHO cells. These results suggest that plasmin induces migration by kringle-mediated binding to alpha(9)beta(1) and simultaneous proteolytic activation of PAR-1. PMID:15247268

  20. On the H$\\alpha$ emission from the $\\beta$ Cephei system

    Schnerr, R S; Oudmaijer, R D; Telting, J H


    Be stars, which are characterised by intermittent emission in their hydrogen lines, are known to be fast rotators. This fast rotation is a requirement for the formation of a Keplerian disk, which in turn gives rise to the emission. However, the pulsating, magnetic B1IV star $\\beta$ Cephei is a very slow rotator that still shows H$\\alpha$ emission episodes like in other Be stars, contradicting current theories. We investigate the hypothesis that the H$\\alpha$ emission stems from the spectroscopically unresolved companion of $\\beta$ Cep. Spectra of the two unresolved components have been separated in the 6350-6850\\AA range with spectro-astrometric techniques, using 11 longslit spectra obtained with ALFOSC at the Nordic Optical Telescope, La Palma. We find that the H$\\alpha$ emission is not related to the primary in $\\beta$ Cep, but is due to its 3.4 magnitudes fainter companion. This companion has been resolved by speckle techniques, but it remains unresolved by traditional spectroscopy. The emission extends fr...

  1. Gross alpha and beta radioactivity in surface soil and drinkable water around a steel processing facility

    F.O. Ogundare


    Full Text Available The mean gross alpha and beta activities in surface soil and drinkable water in the surrounding communities of a steel processing company, following a continuous exposure of workers and dwellers is determined using a low background Gas-less counting system with a solid state silicon PIPS detector for alpha and beta detection. The average activities for gross alpha and beta in soil ranged between 48.5 ± 15.8–64.0 ± 10.0Bq/kg and 411.5 ± 11.5–2710.0 ± 150.0Bq/kg respectively, whereas in water it ranged between 0.0064 ± 0.0001–0.0182 ± 0.0001 Bq/l and 0.046 ± 0.001–0.126 ± 0.001 Bq/l respectively. The average annual committed effective dose from intake of water was between 0.0304 mSv and 0.0678 mSv which is lower than the recommended reference level for ingested dose from drinkable water.

  2. Synthesis of a Round Robin about measurement of gross alpha and beta in various waters

    Since 2011 the CETAMA (Analytical Methods Committee) has organized 3 Round-Robin tests successively to determine the capability of laboratories to measure gross alpha and beta in various waters. Different parameters are considered such as the origin of radionuclides (natural and artificial) and the variation of the salt content (from a low mineralized solution to highly mineralized water such as seawater). Technical specifications are defined within the working group 'Water analysis' in order to solve some problems observed in measurement of gross alpha and beta activity concentrations. The objective is to identify the causes of a discrepancy between the values obtained from the total counts and the sum of the reference values of each radionuclide alone. These Round-Robin tests allow accredited laboratories (or nearly accredited) to train in order to obtain accepted results in French regulatory proficiency tests organized by the IRSN. From the reference values of the various radionuclides (delivered by a primary metrology laboratory) contained in the samples, the averages of the results obtained by the laboratories are calculated and compared. Synthesis of the results highlighted the difficulty in obtaining reference values for gross alpha and gross beta activity. A method is proposed, established from standard and official guidelines based on robust calculation, to determine these assigned values with their associated uncertainty. Feedback from the various interlaboratory comparisons led to suggesting recommendations, particularly in terms of calibration and sample preparation, which allow a significant improvement in the accuracy (trueness and precision) of the method. (authors)

  3. Can {alpha}-tocopherol and {beta}-carotene supplementation reduce adverse radiation effects on salivary glands?

    Funegaard, U.; Johansson, I.; Ericson, T. [Umeaa Univ. (Sweden). Dept. of Cariology; Malmer, B.; Henriksson, R. [Umeaa Univ. (Sweden). Dept. of Oncology


    In this study, we evaluated whether supplementation with antioxidant vitamins can reduce the adverse effects of irradiation on the salivary glands in the rat. Four groups of adult Sprague-Dawley rats were given a basic diet providing 0.6 mg {alpha}-tocopherol and no {beta}-carotene per day. In two groups the basic diet was supplemented with 3.4 mg {alpha}-tocopherol and 6 mg {beta}-carotene per day from 14 days before irradiation until 12 days after complete irradiation. One group of rats given basic diet and one group given supplemented diet were irradiated with 7 Gy daily for five consecutive days. Isoproterenol and pilocarpine-stimulated whole saliva was collected from all rats 2, 4 and 26 weeks after irradiation. Vitamin-supplemented irradiated rats had higher secretion rates on all three occasions compared with those of irradiated rats given basic diet. The changes in saliva composition seen in irradiated rats were less accentuated in vitamin-supplemented, irradiated rats. The proportions of acinar cells were significantly decreased both in parotid and submandibular glands 26 weeks after irradiation. Supplementation with {alpha}-tocopherol and {beta}-carotene did not alter the morphology of the glands. (author).

  4. Combination of digital autoradiography and alpha track analysis to reveal the distribution of definite alpha- and beta-emitting nuclides in contaminated samples

    Digital autoradiography using Imaging Plate is commonly employed for searching 'hot' particles in the contaminated soil, sediment and aerosol probes. However digital radiography images combined with Alpha Track radiography data could provide much more information about micro-distribution of different alpha- and beta- nuclides. The discrimination method to estimate the distribution of radionuclides that are the main contributors to the total radioactivity (90Sr/90Y, 137Cs, 241Am) has been developed on the case of artificial reservoir V-17 (PA 'Mayak'). The bottom sediments and hydrobionts probes collected from V-17 along with the standards of 137Cs, 90Sr/90Y and 241Am have been exposed for a short time (15 min) using a stack of 3 Imaging Plates (Cyclone Plus Storage Phosphor System, Perkin Elmer). The attenuation of photostimulated luminescence (PSL) intensity from layer to layer of the Imaging Plates depends on the type and energy of radiation. Integrated approach using PSL attenuation in the samples and standards (digital radiography) along with Alpha Track radiography and gamma-spectroscopy of the preparation was used to estimate the contribution of the main nuclides in specific parts of contaminated samples. The observation of the 90Sr/90Y and 137Cs activity maxima could help to find the phases which are responsible for preferential sorption of the nuclides. Document available in abstract form only. (authors)

  5. Screening procedures for alpha, beta and gamma emitting radionuclides in urine

    The gross actinide and beta screening methods currently used by the Bioassay Laboratory at Chalk River Nuclear Laboratories have been documented and tested. The gross gamma method has also been documented. The gross actinide method was tested with Th-nat, Pu-239, Np-237, Am-241 and Cm-244 and the average percent recoveries were 90, 99, 45, 72 and 78, respectively. The gross beta method was tested with Sr-90/Y-90, Ce-144/Pr-144, Pm-147 and Ba-133 and the average percent recoveries were 78, 100, 46 and 46, respectively. Detection limits for the gross actinide (alpha) method are found to be about 0.4 mBq and about 39 mBq for the gross beta method

  6. Closed headpiece of integrin [alpah]IIb[beta]3 and its complex with an [alpha]IIb[beta]3-specific antagonist that does not induce opening

    Zhu, Jieqing; Zhu, Jianghai; Negri, Ana; Provasi, Davide; Filizola, Marta; Coller, Barry S.; Springer, Timothy A. (Sinai); (Rockefeller); (CH-Boston)


    The platelet integrin {alpha}{sub IIb}{beta}{sub 3} is essential for hemostasis and thrombosis through its binding of adhesive plasma proteins. We have determined crystal structures of the {alpha}{sub IIb}{beta}{sub 3} headpiece in the absence of ligand and after soaking in RUC-1, a novel small molecule antagonist. In the absence of ligand, the {alpha}{sub IIb}{beta}{sub 3} headpiece is in a closed conformation, distinct from the open conformation visualized in presence of Arg-Gly-Asp (RGD) antagonists. In contrast to RGD antagonists, RUC-1 binds only to the {alpha}{sub IIb} subunit. Molecular dynamics revealed nearly identical binding. Two species-specific residues, {alpha}{sub IIb} Y190 and {alpha}{sub aIIb} D232, in the RUC-1 binding site were confirmed as important by mutagenesis. In sharp contrast to RGD-based antagonists, RUC-1 did not induce {alpha}{sub IIb}{beta}{sub 3} to adopt an open conformation, as determined by gel filtration and dynamic light scattering. These studies provide insights into the factors that regulate integrin headpiece opening, and demonstrate the molecular basis for a novel mechanism of integrin antagonism.

  7. Patterns of alpha, beta and gamma diversity of the herpetofauna in Mexico’s Pacific lowlands and adjacent interior valleys

    García, A.


    Full Text Available The latitudinal distribution patterns of alpha, beta and gamma diversity of reptiles, amphibians and herpetofauna were analyzed using individual binary models of potential distribution for 301 species predicted by ecological modelling for a grid of 9,932 quadrants of ~25 km2 each. We arranged quadrants in 312 latitudinal bands in which alpha, beta and gamma values were determined. Latitudinal trends of all scales of diversity were similar in all groups. Alpha and gamma responded inversely to latitude whereas beta showed a high latitudinal fluctuation due to the high number of endemic species. Alpha and gamma showed a strong correlation in all groups. Beta diversity is an important component of the herpetofauna distribution patterns as a continuous source of species diversity throughout the region.

  8. Synergistic effects of interleukin-1beta, interleukin-6, and tumor necrosis factor-alpha: central monoamine, corticosterone, and behavioral variations.

    Brebner, K; Hayley, S; Zacharko, R; Merali, Z; Anisman, H


    The proinflammatory cytokines interleukin-1beta (IL-1beta), IL-6, and tumor necrosis factor-alpha (TNF-alpha) influence neuroendocrine activity, promote central neurotransmitter alterations, and induce a constellation of symptoms collectively referred to as sickness behaviors. These cytokines may also elicit anxiety and anhedonia, and have been associated with psychological disturbances in humans. In the present investigation, systemic IL-1beta and TNF-alpha dose-dependently and synergistically disrupted consumption of a highly palatable food source (chocolate milk), possibly reflecting anorexia or anhedonia engendered by the treatments. As well, these cytokines synergistically increased plasma corticosterone levels. Although IL-1beta and TNF-alpha provoked variations of amine turnover in the hypothalamus, locus coeruleus, and central amygdala, synergistic effects were not evident in this respect. Nevertheless, in view of the central amine variations induced by the cytokines, it is suggested that immune activation may come to influence complex behavioral processes, as well as affective state. PMID:10788757

  9. Assembly, intracellular processing, and expression at the cell surface of the human alpha beta T cell receptor/CD3 complex. Function of the CD3-zeta chain

    Geisler, C; Kuhlmann, J; Rubin, B


    complex, the role of the CD3 chains for the TCR/CD3 expression have not been experimentally addressed in human T cells. In this study the function of the CD3-zeta chain for the assembly, intracellular processing, and expression of the TCR/CD3 complex in the human leukemic T cell line Jurkat was......The TCR/CD3 complex is a multimeric protein complex composed of a minimum of seven transmembrane chains (TCR alpha beta-CD3 gamma delta epsilon zeta 2). Whereas earlier studies have demonstrated that both the TCR-alpha and -beta chains are required for the cell surface expression of the TCR/CD3...... investigated. The results indicate that: 1) CD3-zeta is required for the cell surface expression of the TCR/CD3 complex; 2) the pentameric form (TCR alpha beta-CD3 gamma delta epsilon) of the TCR/CD3 complex and single TCR chains associated with CD3 (TCR alpha-CD3 gamma delta epsilon and TCR beta-CD3 gamma...

  10. Internal {alpha} activity: localisation, compositional associations and effects on OSL signals in quartz approaching {beta} saturation

    Burbidge, C.I. [Instituto Tecnologico e Nuclear, Sacavem (Portugal)], E-mail:; Dias, M.I.; Prudencio, M.I. [Instituto Tecnologico e Nuclear, Sacavem (Portugal); Rebelo, L.P. [DGM, INETI, Departamento de Geologia Marinha, Alfragide (Portugal); Cardoso, G. [Instituto Tecnologico e Nuclear, Sacavem (Portugal); Brito, P. [DGM, INETI, Departamento de Geologia Marinha, Alfragide (Portugal)


    Luminescence signals from hydrofluoric acid etched grains of quartz from Mozambican dunes were investigated in terms of elemental impurities, structural defects, and their relationship to internal {alpha} activity, to examine the potential for this to cause differences in signal levels obtainable from natural and laboratory irradiated samples. Optical and scanning electron microscopy (SEM), X-ray fluorescence (XRF) and instrumental neutron activation analysis (INAA) indicated the presence of various types of quartz and mineralogical inclusions. A spatial association of Th and U with Fe in structural defects was observed. Fe concentrations and inclusion sizes indicated that internal {alpha} dose rate would affect the defects that contained these impurities, but would be insignificant to the bulk quartz. A broad range of optically sensitive thermoluminescence (TL) peaks were observed from this material, and indicated a preheating regime of 260 deg. C for 30 s to minimise effects of the observed inclusions and defects on absorbed dose determinations by optically stimulated luminescence (OSL). Growth in OSL with dose from etched coarse grains preheated in this way approached saturation by 332 Gy of {beta} irradiation ({sup 90}Sr/{sup 90}Y) and by 4 kGy of {alpha} irradiation (E {approx} 3.5 MeV: approximate natural soil spectrum average, using converted dose rate from {sup 241}Am). This indicated {alpha}-efficiency (k{sub eff}) at saturation of less than 0.08. However, the OSL decay curves contained a small 'medium' component. Structural defects introduced by milling the grains produced a larger 'medium' component with a similar decay rate under optical stimulation, which exhibited high saturation doses (>32 kGy{alpha}, >8.4 kGy{beta}) and {alpha}-efficiency (k{sub eff} = 0.34). Maximum dose normalised OSL signals from the milled material greatly exceeded those obtainable from the whole etched grains. It is inferred that the presence of structural

  11. Hydrogen Lyman-alpha and Lyman-beta radiances and profiles in polar coronal holes

    Tian, Hui; Curdt, Werner; Vial, Jean-Claude


    The hydrogen Lyman-alpha plays a dominant role in the radiative energy transport in the lower transition region, and is important for the stud- ies of transition-region structure as well as solar wind origin. We investigate the Ly-alpha profiles obtained by SUMER in coronal holes and quiet Sun. In a subset of these observations, also the Hi Lyman-beta, Si iii, and O vi lines were (quasi-) simultaneously recorded. We find that the distances between the two peaks of Ly-alpha profiles are larger in coronal holes than in the quiet Sun, indicating a larger opacity in coronal holes. This difference might result from the different magnetic structures or the different radiation fields in the two regions. Most of the Ly-beta profiles in the coronal hole have a stronger blue peak, in contrast to those in quiet-Sun regions. Whilst in both regions the Ly-alpha profiles are stronger in the blue peak. Although the asymmetries are likely to be produced by differential flows in the solar atmosphere, their detailed formation ...

  12. Electron momentum density and band structure calculations of {alpha}- and {beta}-GeTe

    Vadkhiya, Laxman [Department of Physics, University College of Science, M.L. Sukhadia University, Udaipur 313001, Rajasthan (India); Arora, Gunjan [Department of Physics, Techno India NJR Institute of Technology, Udaipur 313002, Rajasthan (India); Rathor, Ashish [Department of Physics, University College of Science, M.L. Sukhadia University, Udaipur 313001, Rajasthan (India); Ahuja, B.L., E-mail: [Department of Physics, University College of Science, M.L. Sukhadia University, Udaipur 313001, Rajasthan (India)


    We have measured isotropic experimental Compton profile of {alpha}-GeTe by employing high energy (662 keV) {gamma}-radiation from a {sup 137}Cs isotope. To compare our experiment, we have also computed energy bands, density of states, electron momentum densities and Compton profiles of {alpha}- and {beta}-phases of GeTe using the linear combination of atomic orbitals method. The electron momentum density is found to play a major role in understanding the topology of bands in the vicinity of the Fermi level. It is seen that the density functional theory (DFT) with generalised gradient approximation is relatively in better agreement with the experiment than the local density approximation and hybrid Hartree-Fock/DFT. - Highlights: > Compton profile of {alpha}-GeTe using a 20 Ci {sup 137}Cs Compton spectrometer. > Compared experimental Compton data with density functional theory. > Reported energy bands and density of states of {alpha}- and {beta}-GeTe. > EVED profiles analysed to check the covalent character.

  13. The influence of internal stresses on the fracture toughness of {alpha}/{beta} titanium alloys

    Helbert, A.L.; Feaugas, X.; Clavel, M.


    The influence of internal stresses on fracture toughness was investigated in {alpha}/{beta} titanium alloys. It was shown that the direct linkage of K{sub IC} to various microstructural parameters was not so conclusive, since the different parameters act simultaneously on fracture toughness. On the contrary, the metallurgical parameters change the plastic strain incompatibilities inside the material. Thus X, which is a macroscopic measurement of these incompatibilities, is the relevant parameter to account for the different metallurgical influences on toughness. The influence on X of the {alpha}-phase percentage, aspect ratio, and the secondary {alpha}-phase percentage was determined, and it was established that low internal stresses could provide high fracture toughness. The present work also showed the ability of a modified Gurson-Tvergaard (GT) model to calculate the experimental K{sub IC} value.

  14. Red cell genetic abnormalities in Peninsular Arabs: sickle haemoglobin, G6PD deficiency, and alpha and beta thalassaemia.

    White, J. M.; Byrne, M; Richards, R; T. Buchanan; Katsoulis, E; Weerasingh, K


    The frequencies of four major red cell genetic defects, sickle haemoglobin (Hb S), glucose 6 phosphate dehydrogenase deficiency (G6PD), and alpha and beta thalassaemia, have been determined in nearly 5000 subjects from the three major Peninsular Arab States, namely Yemen (North and South), the United Arab Emirates, and Oman. All four defects are common with an overall pattern of alpha thalassaemia greater than G6PD deficiency greater than beta thalassaemia greater than Hb A/S. However, the fr...

  15. Impaired platelet aggregation and sustained bleeding in mice lacking the fibrinogen motif bound by integrin alpha IIb beta 3.

    Holmbäck, K; Danton, M J; Suh, T T; Daugherty, C. C.; Degen, J L


    Blood loss at sites of vascular rupture is controlled by the adhesion and aggregation of platelets and the formation of an insoluble fibrin matrix. Fibrinogen is considered to be critical in these processes by both providing an abundant dimeric ligand for alpha IIb beta 3-mediated platelet aggregation, and serving as the fundamental building block of the fibrin polymer. To establish an in vivo model system to examine in detail the importance of alpha IIb beta 3-fibrinogen interactions in plat...

  16. De novo backbone and sequence design of an idealized alpha/beta-barrel protein: Evidence of stable tertiary structure

    Offredi, Fabrice; Dubail, Fabien; Kischel, Philippe; Sarinski, K.; Stern, A S; Van de Weerdt, Cécile; Hoch, J. C.; Prosperi, Christelle; François, Jean-Marie; Mayo, S. L.; Martial, Joseph


    We have designed, synthesized, and characterized a 216 amino acid residue sequence encoding a putative idealized alpha/beta-barrel protein. The design was elaborated in two steps. First, the idealized backbone was defined with geometric parameters representing our target fold: a central eight parallel-stranded beta-sheet surrounded by eight parallel alpha-helices, connected together with short structural turns on both sides of the barrel. An automated sequence selection algorithm, based on th...

  17. Accelerations of {epsilon}+{alpha}{yields}{beta} transformation and sintering of iron silicide by addition of Pd; Pd tenka ni yoru keikatetsu no {epsilon}+{alpha}{yields}{beta} hentai to shoketsu no sokushin

    Kato, M.; Yamamoto, N.; Takeda, T. [Isuzu Advanced Engineering Center Ltd., Kanagawa (Japan); Hayashi, K. [The University of Tokyo, Tokyo (Japan). Institute of Industrial Science


    FeSi2 ({beta} phase) semiconducting iron silicide, which is expected to be widely used as a thermoelectric material in high temperature environment, is formed below 1259K by the peritectoid reaction of FeSi ({epsilon}) and Fe2Si5 ({alpha}) two metallic phases. Because the transformation of {epsilon} + {alpha} {yields} {beta} caused by this peritectoid reaction occurs considerably slowly, the iron silicide material which is produced by sintering of the powder at temperatures above 1259K has to be isothermally heat-treated for at least 180ks at about 1120K after the sintering so that the transformation occurs completely. We have found that the transformation was drastically accelerated by the addition of a small amount of Pd in the same way as Cu; the isothermal heat-treatment time necessary for the completion of the transformation was reduced to about 1/60. The sintering time needed for the almost full densification of the powder by pressure DCL sintering (DCL; direct current loading) was also reduced. A hypothesis for the mechanisms was proposed. 15 refs., 7 figs., 2 tabs.

  18. Accurate measurements of surface emission rate for large-area alpha and beta reference sources

    For alpha emitters and beta emitters with maximum beta energy greater than 0.150 MeV, the characteristics of reference sources for the calibration of surface contamination monitors are specified by the international standard ISO 8769. According to this standard, the surface emission rate of reference sources has to be measured by absolute methods or by using an instrument that has been calibrated by means of sources that has been measured absolutely. Moreover, the surface emission rate has to be measured by the national standards laboratory with an uncertainty which must not exceed 3% (one standard deviation). In this paper, the counting system and the experimental conditions needed for accurate measurements of the surface emission rate are presented. The uncertainty of such measurements is much smaller than 3%. The evaluation of this uncertainty is also described. The counting system used for absolute alpha and beta surface emission rate measurements is composed of a large area, gas-flow, windowless proportional detector, an integral and a spectrometric counting channels. The method of measurement for alpha and beta surface emission rate is very simple but it is necessary to achieve the optimum experimental conditions of counting for obtaining accurate measurement results. Thus, the proportional detector has to work under a continuous and stable gas-flow and its plateau has to be long with a very low slope. To obtain a counting efficiency of 100%, it has to use a tight detector and a very pure counting gas. Additionally, the detector must be flushed and then operated under a steady gas-flow for several hours prior to measurements in order to be cleaned of air impurities. To perform alpha and beta surface emission rate measurements we optimized first the conditions of counting. For beta sources, the discrimination level has been adjusted by means of a 55 Fe source. Using this spectrum, we checked the stability of the counting system because the peak, corresponding

  19. Expression of human alpha 2-adrenergic receptors in adipose tissue of beta 3-adrenergic receptor-deficient mice promotes diet-induced obesity.

    Valet, P; Grujic, D; Wade, J; Ito, M; Zingaretti, M C; Soloveva, V; Ross, S R; Graves, R A; Cinti, S; Lafontan, M; Lowell, B B


    Catecholamines play an important role in controlling white adipose tissue function and development. beta- and alpha 2-adrenergic receptors (ARs) couple positively and negatively, respectively, to adenylyl cyclase and are co-expressed in human adipocytes. Previous studies have demonstrated increased adipocyte alpha 2/beta-AR balance in obesity, and it has been proposed that increased alpha 2-ARs in adipose tissue with or without decreased beta-ARs may contribute mechanistically to the development of increased fat mass. To critically test this hypothesis, adipocyte alpha 2/beta-AR balance was genetically manipulated in mice. Human alpha 2A-ARs were transgenically expressed in the adipose tissue of mice that were either homozygous (-/-) or heterozygous (+/-) for a disrupted beta 3-AR allele. Mice expressing alpha 2-ARs in fat, in the absence of beta 3-ARs (beta 3-AR -/- background), developed high fat diet-induced obesity. Strikingly, this effect was due entirely to adipocyte hyperplasia and required the presence of alpha2-ARs, the absence of beta 3-ARs, and a high fat diet. Of note, obese alpha 2-transgenic beta 3 -/- mice failed to develop insulin resistance, which may reflect the fact that expanded fat mass was due to adipocyte hyperplasia and not adipocyte hypertrophy. In summary, we have demonstrated that increased alpha 2/beta-AR balance in adipocytes promotes obesity by stimulating adipocyte hyperplasia. This study also demonstrates one way in which two genes (alpha 2 and beta 3-AR) and diet interact to influence fat mass. PMID:10948198

  20. Increased expression of integrin alpha2 and abnormal response to TGF-beta1 in hereditary gingival fibromatosis.

    Zhou, J.; Meng, L.; Ye, X.Q.; Hoff, J.W. von den; Bian, Z.


    OBJECTIVE: To investigate the possible correlation between integrin alpha1, alpha2, and beta1 expression and excessive collagen synthesis in fibroblasts from 3 unrelated Chinese families with hereditary gingival fibromatosis (HGF). DESIGN: Gingival fibroblasts from three Chinese HGF patients and thr

  1. Alpha/Beta and Gamma Interferons Are Induced by Infection with Noncytopathic Bovine Viral Diarrhea Virus In Vivo

    Charleston, B; Brackenbury, L.S; Carr, B. V.; Fray, M D; Hope, Jayne; Howard, CJ; Morrison, Ivan


    In contrast to the results of previous in vitro studies, experimental infection of calves with noncytopathic bovine viral diarrhea virus (ncpBVDV) was found to induce strong alpha/beta and gamma interferon responses in gnotobiotic animals. These responses were associated with depressed levels of transforming growth factor beta (TGF-beta) in serum. The results of this study indicate that the immunosuppression caused by ncpBVDV is not associated with low interferon responses or elevated levels ...

  2. Adrenalectomy abolishes antagonism of alpha-adrenoceptor-mediated hypotension by a beta-blocker in conscious rats.

    Tabrizchi, R.; Pang, C. C.


    1. The effects of a single bolus injection of propranolol, atenolol or ICI 118,551, non-selective beta-, selective beta 1- and selective beta 2-adrenoceptor antagonists, respectively, on mean arterial pressure (MAP) and plasma catecholamine concentrations were examined in seven groups of conscious and unrestrained adrenalectomized rats receiving a continuous infusion of the alpha-adrenoceptor antagonist phentolamine. In all rats adrenaline was undetectable in the plasma four days after adrena...

  3. An analytical model to calculate absorbed fractions for internal dosimetry with alpha, beta and gamma emitters

    Ernesto Amato


    Full Text Available We developed a general model for the calculation of absorbed fractions in ellipsoidal volumes of soft tissue uniformly filled with alpha, beta and gamma emitting radionuclides. The approach exploited Monte Carlo simulations with the Geant4 code to determine absorbed fractions in ellipsoids characterized by a wide range of dimensions and ellipticities, for monoenergetic emissions of each radiation type. The so-obtained absorbed fractions were put in an analytical relationship with the 'generalized radius', calculated as 3V/S, where V is the ellipsoid volume and S its surface. Radiation-specific parametric functions were obtained in order to calculate the absorbed fraction of a given radiation in a generic ellipsoidal volume. The dose from a generic radionuclide can be calculated through a process of summation and integration over the whole radionuclide emission spectrum, profitably implemented in an electronic spreadsheet. We compared the results of our analytical calculation approach with those obtained from the OLINDA/EXM computer software, finding a good agreement in a wide range of sphere radii, for the high-energy pure beta emitter 90Y, the commonly employed beta-gamma emitter 131I, and the pure alpha emitter 213Po. The generality of our approach makes it useful an easy to implement in clinical dosimetry calculations as well as in radiation safety estimations when doses from internal radionuclide uptake are to be taken into account.

  4. Characterization of the alpha and beta subunits of casein kinase 2 by far-UV CD spectroscopy

    Issinger, O G; Brockel, C; Boldyreff, B; Pelton, J T


    Although Chou-Fasman calculations of the secondary structure of recombinant casein kinase 2 subunits alpha and beta suggest they have a similar overall conformation, circular dichroism (CD) studies show that substantial differences in the conformation of the two subunits exist. In addition......, no changes in the far-UV CD spectrum of the alpha subunit are observed in the presence of casein or the synthetic decapeptide substrate RRRDDDSDDD. Furthermore, the alpha-helical structure of the alpha subunit (but not the beta subunit) can be increased in the presence of stoichiometric amounts of...... heparin, presumably by its binding to the polylysine stretch at amino acid positions 74-77. Heat denaturation experiments (25-90 degrees C) support the notion that heparin may provide a local protective function. A similar but much larger effect was also observed in the presence of the beta subunit only...

  5. Structural Basis of the CD8[alpha beta]/MHC Class I Interaction: Focused Recognition Orients CD8[beta] to a T Cell Proximal Position[superscript 1,2

    Wang, Rui; Natarajan, Kannan; Margulies, David H.; (NIH)


    In the immune system, B cells, dendritic cells, NK cells, and T lymphocytes all respond to signals received via ligand binding to receptors and coreceptors. Although the specificity of T cell recognition is determined by the interaction of T cell receptors with MHC/peptide complexes, the development of T cells in the thymus and their sensitivity to Ag are also dependent on coreceptor molecules CD8 (for MHC class I (MHCI)) and CD4 (for MHCII). The CD8{alpha}{beta} heterodimer is a potent coreceptor for T cell activation, but efforts to understand its function fully have been hampered by ignorance of the structural details of its interactions with MHCI. In this study we describe the structure of CD8{alpha}{beta} in complex with the murine MHCI molecule H-2D{sup d} at 2.6 {angstrom} resolution. The focus of the CD8{alpha}{beta} interaction is the acidic loop (residues 222-228) of the {alpha}3 domain of H-2D{sup d}. The {beta} subunit occupies a T cell membrane proximal position, defining the relative positions of the CD8{alpha} and CD8{beta} subunits. Unlike the CD8{alpha}{alpha} homodimer, CD8{alpha}{beta} does not contact the MHCI {alpha}{sub 2}- or {beta}{sub 2}-microglobulin domains. Movements of the CD8{alpha} CDR2 and CD8{beta} CDR1 and CDR2 loops as well as the flexibility of the H-2D{sup d} CD loop facilitate the monovalent interaction. The structure resolves inconclusive data on the topology of the CD8{alpha}{beta}/MHCI interaction, indicates that CD8{beta} is crucial in orienting the CD8{alpha}{beta} heterodimer, provides a framework for understanding the mechanistic role of CD8{alpha}{beta} in lymphoid cell signaling, and offers a tangible context for design of structurally altered coreceptors for tumor and viral immunotherapy.

  6. Use of synthetic peptides to locate novel integrin alpha2beta1-binding motifs in human collagen III.

    Raynal, Nicolas; Hamaia, Samir W; Siljander, Pia R-M; Maddox, Ben; Peachey, Anthony R; Fernandez, Rafael; Foley, Loraine J; Slatter, David A; Jarvis, Gavin E; Farndale, Richard W


    A set of 57 synthetic peptides encompassing the entire triplehelical domain of human collagen III was used to locate binding sites for the collagen-binding integrin alpha(2)beta(1). The capacity of the peptides to support Mg(2+)-dependent binding of several integrin preparations was examined. Wild-type integrins (recombinant alpha(2) I-domain, alpha(2)beta(1) purified from platelet membranes, and recombinant soluble alpha(2)beta(1) expressed as an alpha(2)-Fos/beta(1)-Jun heterodimer) bound well to only three peptides, two containing GXX'GER motifs (GROGER and GMOGER, where O is hydroxyproline) and one containing two adjacent GXX'GEN motifs (GLKGEN and GLOGEN). Two mutant alpha(2) I-domains were tested: the inactive T221A mutant, which recognized no peptides, and the constitutively active E318W mutant, which bound a larger subset of peptides. Adhesion of activated human platelets to GER-containing peptides was greater than that of resting platelets, and HT1080 cells bound well to more of the peptides compared with platelets. Binding of cells and recombinant proteins was abolished by anti-alpha(2) monoclonal antibody 6F1 and by chelation of Mg(2+). We describe two novel high affinity integrin-binding motifs in human collagen III (GROGER and GLOGEN) and a third motif (GLKGEN) that displays intermediate activity. Each motif was verified using shorter synthetic peptides. PMID:16326707

  7. Relative response of TL and component-resolved OSL to alpha and beta radiations in annealed sedimentary quartz

    Polymeris, George S., E-mail: [Archaeometry Laboratory, Cultural and Educational Technology Institute, R.C. ' ATHENA' , Tsimiski 58, 67100 Xanthi (Greece); ISIK University, Faculty of Science and Arts, Physics Department, Sile 34980, Istanbul (Turkey); Afouxenidis, Dimitrios; Raptis, Spyridoula [Archaeometry Laboratory, Cultural and Educational Technology Institute, R.C. ' ATHENA' , Tsimiski 58, 67100 Xanthi (Greece); Nuclear Physics Laboratory, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece); Liritzis, Ioannis [Laboratory of Archaeometry, Dept. of Mediterranean Studies, University of the Aegean, 1 Demokratias Ave., 85100 Rhodes (Greece); Tsirliganis, Nestor C. [Archaeometry Laboratory, Cultural and Educational Technology Institute, R.C. ' ATHENA' , Tsimiski 58, 67100 Xanthi (Greece); Kitis, George [Nuclear Physics Laboratory, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece)


    Knowledge of the relative luminescence response to alpha and beta radiation is very important in TL and OSL dating. In the present study the relative alpha to beta response is studied in a sedimentary quartz sample, previously fired at 900 deg. C for 1 h, in the dose region between 1 and 128 Gy, for both thermoluminescence (TL) and linearly modulated optically stimulated luminescence (LM - OSL). The LM - OSL measurements were performed at room temperature and at 125 deg. C. All OSL signals were deconvolved into their individual components. Comparison of OSL curves after alpha and beta irradiation strongly supports that quartz OSL components follow first order kinetics in both cases. In the case of TL, the relative alpha to beta response is found to be very different for each TL glow-peak, but it does not depend strongly on irradiation dose. In the case of LM - OSL measurements, it is found that the relative behaviour of the alpha to beta response is different for three distinct regions, namely the fast OSL component, the region of medium OSL component originating from the TL glow-peak at 110 deg. C when stimulation takes place at room temperature and finally the region of slow OSL component. Following stimulation at ambient temperature, the relative alpha to beta response of all components was not observed to depend significantly on dose, with the value of ratio being 0.03 and a tendency to decrease with increasing dose. However, in the case of measurements performed at 125 deg. C, the relative response of the fast components is much enhanced, and for the remaining components it increases with increasing dose. Special care must be taken to examine the relative alpha to beta response of the fast component at 125 deg. C which contrasts the relative response of the TL peak at ca. 325 deg. C. The implications for the dating of annealed quartz are also briefly discussed. - Highlights: > Relative alpha to beta response for TL and LM-OSL is studied in annealed sedimentary

  8. Skylab-barium alpha and beta L = 6 field-line tracing experiments

    Events SKYLAB-BARIUM ALPHA (27 November 1973) and BETA (4 December 1973) were shaped-charge barium field-line tracing experiments near L approximately equal to 6, conducted jointly by the Los Alamos Scientific Laboratory and the University of Alaska Geophysical Institute. Image-orthicon and pulsed intensified auroral cameras provided data for triangulating the fast ion streaks. Using the POGO 10-68, epoch 1965.0, field-line model with Mead-Fairfield corrections for the outer field, the triangulated positions of the fast ion streak were projected down to the 100 km altitude northern conjugate surface. The projected positions moved toward magnetic east with a velocity of 725 m/sec for both SKYLAB-BARIUM ALPHA and BETA. Assuming only an E x B/B2 force, this drift velocity is consistent with an electric field toward magnetic south of 39 mV/m. Radiometric analysis of the filtered, intensified auroral camera records gave observed peak radiance values of about 2 x 10-11 watts/cm2-Sr in the 455.4 nm line of Ba+. The barium in the portion of the ion streak for which radiometric data were obtained had initial injection velocities of 9.5 to 13.5 km/sec in both events. This portion of the ion streak for both SKYLAB-BARIUM ALPHA and BETA contained approximately 4 x 1023 ions compared to the 6.4 x 1024 atoms contained in the barium liner. Ion inventory estimates are based on a solution of the statistical equilibrium equations. Corrections have been made in the ion inventory calculations for Doppler shifts of the solar spectrum as received in the rest frame of the high-velocity barium ions

  9. Gross Alpha Beta Radioactivity in Air Filters Measured by Ultra Low Level α/β Counter

    Cfarku, Florinda; Bylyku, Elida; Deda, Antoneta; Dhoqina, Polikron; Bakiu, Erjona; Perpunja, Flamur


    Study of radioactivity in air as very important for life is done regularly using different methods in every country. As a result of nuclear reactors, atomic centrals, institutions and laboratories, which use the radioactivity substances in open or closed sources, there are a lot radioactive wastes. Mixing of these wastes after treatment with rivers and lakes waters makes very important control of radioactivity. At the other side nuclear and radiological accidents are another source of the contamination of air and water. Due to their radio toxicity, especially those of Sr90, Pu239, etc. a contamination hazard for human begins exist even at low concentration levels. Measurements of radioactivity in air have been performed in many parts of the world mostly for assessment of the doses and risk resulting from consuming air. In this study we present the results of international comparison organized by IAEA Vienna, Austria for the air filters spiked with unknown Alpha and Beta Activity. For the calibration of system we used the same filters spiked: a) with Pu-239 as alpha source; b) Sr-90 as beta source and also the blank filter. The measurements of air filter samples after calibration of the system are done with Ultra Low Level α/β Counter (MPC 9604) Protean Instrument Corporation. The high sensitivity of the system for the determination of the Gross Alpha and Beta activity makes sure detection of low values activity of air filters. Our laboratory results are: Aα = (0.19±0.01) Bq/filter and Aα (IAEA) = (0.17±0.009) Bq/filter; Aβ = (0.33±0.009) Bq/filter and Aβ (IAEA) = (0.29±0.01) Bq/filter. As it seems our results are in good agreement with reference values given by IAEA (International Atomic Energy Agency).

  10. Alpha and beta EEG power reflects L-dopa acute administration in parkinsonian patients

    Jean-Marc eMelgari


    Full Text Available Aim. To evaluate the effect of an acute L-dopa administration on eye-closed resting state electroencephalographic (EEG activity of cognitively preserved Parkinsonian patients. Methods. We examined 24 right-handed patients diagnosed as uncomplicated probable Parkinson’s disease (PD. Each patient underwent UPDRS-part-III evaluation before and 60 minutes after an oral load of L-dopa-methyl-ester/carbidopa 250/25 mg. Resting condition eyes-closed EEG data were recorded both pre- and post L-dopa load. Absolute EEG power values were calculated at each scalp derivation for Delta, Theta, Alpha and Beta frequency bands. UPDRS scores (both global and subscale scores and EEG data (power values of different frequency bands for each scalp derivation were submitted to a statistical analysis to compare Pre e Post L-Dopa conditions. Finally, a correlation analysis was carried out between EEG spectral content and UPDRS scores. Results. Considering EEG power spectral analysis, no statistically significant differences arose on Delta and Theta bands after L-dopa intake. Conversely, Alpha and Beta rhythms significantly increased on centro-parietal scalp derivations, as a function of L-dopa administration. Correlation analysis indicated a significant negative correlation between Beta power increase on centro-parietal areas and UPDRS subscores (Rigidity of arms and Bradykinesia. A minor significant negative correlation was also found between Alpha band increase and resting tremor. Conclusions. Assuming that a significant change in EEG power spectrum after L-dopa intake may be related to dopaminergic mechanisms, our findings are consistent with the hypothesis that dopaminergic defective networks are implicated in cortical oscillatory abnormalities at rest in non-demented PD patients.

  11. Alpha and beta EEG power reflects L-dopa acute administration in parkinsonian patients

    Melgari, Jean-Marc; Curcio, Giuseppe; Mastrolilli, Francesca; Salomone, Gaetano; Trotta, Laura; Tombini, Mario; di Biase, Lazzaro; Scrascia, Federica; Fini, Rita; Fabrizio, Emma; Rossini, Paolo Maria; Vernieri, Fabrizio


    Aim: To evaluate the effect of an acute L-dopa administration on eye-closed resting state electroencephalographic (EEG) activity of cognitively preserved Parkinsonian patients. Methods: We examined 24 right-handed patients diagnosed as uncomplicated probable Parkinson’s disease (PD). Each patient underwent Unified Parkinson’s Disease Rating Scale (UPDRS)-part-III evaluation before and 60 min after an oral load of L-dopa-methyl-ester/carbidopa 250/25 mg. Resting condition eyes-closed EEG data were recorded both pre- and post L-dopa load. Absolute EEG power values were calculated at each scalp derivation for Delta, Theta, Alpha and Beta frequency bands. UPDRS scores (both global and subscale scores) and EEG data (power values of different frequency bands for each scalp derivation) were submitted to a statistical analysis to compare Pre and Post L-Dopa conditions. Finally, a correlation analysis was carried out between EEG spectral content and UPDRS scores. Results: Considering EEG power spectral analysis, no statistically significant differences arose on Delta and Theta bands after L-dopa intake. Conversely, Alpha and Beta rhythms significantly increased on centro-parietal scalp derivations, as a function of L-dopa administration. Correlation analysis indicated a significant negative correlation between Beta power increase on centro-parietal areas and UPDRS subscores (Rigidity of arms and Bradykinesia). A minor significant negative correlation was also found between Alpha band increase and resting tremor. Conclusions: Assuming that a significant change in EEG power spectrum after L-dopa intake may be related to dopaminergic mechanisms, our findings are consistent with the hypothesis that dopaminergic defective networks are implicated in cortical oscillatory abnormalities at rest in non-demented PD patients. PMID:25452725

  12. BEGe detector response to alpha and beta-radiation near its p+ electrode

    In Phase II of the GERDA (Germanium Detector Array) experiment Broad Energy Germanium (BEGe) detectors will continue the search for the neutrinoless double beta decay (0νββ) of 76Ge. The main feature of these detectors is their small p+ electrode used for signal read-out. Due to the thin dead layer of the p+ contact, surface events close to this electrode represent a potential background for the search of 0νββ. A study was conducted to determine the response of the detector to alpha and beta-radiation using movable collimated sources within a custom-build cryostat. Preliminary results of this study and a possible method to discriminate these events will be presented.

  13. Metabolismus der Phenylpropene Methyleugenol, (\\(\\it E \\))-Methylisoeugenol sowie alpha-, beta- und gamma-Asaron

    Cartus, Alexander T.


    Methyleugenol (ME), (\\(\\it E \\))-Methylisoeugenol (MIE), alpha-Asaron (aA), beta-Asaron (bA) und gamma-Asaron (gA) sind natürlich vorkommende Pflanzeninhaltsstoffe aus der Klasse der Phenylpropene (PP) und Bestandteil der menschlichen Ernährung. ME, aA und bA erwiesen sich im Tierversuch als hepatokanzerogen. MIE und gA wurden bislang nicht untersucht. Die allylischen Hepatokanzerogene Estragol und Safrol werden im Verlauf des Fremdstoff-metabolismus durch Cytochrom P450-Enzyme (CYP) in 1‘-Po...

  14. Highly Potent, Water Soluble Benzimidazole Antagonist for Activated (alpha)4(beta)1 Integrin

    Carpenter, R D; Andrei, M; Lau, E Y; Lightstone, F C; Liu, R; Lam, K S; Kurth, M J


    The cell surface receptor {alpha}{sub 4}{beta}{sub 1} integrin, activated constitutively in lymphoma, can be targeted with the bisaryl urea peptidomimetic antagonist 1 (LLP2A). However, concerns on its preliminary pharmacokinetic (PK) profile provided an impetus to change the pharmacophore from a bisaryl urea to a 2-arylaminobenzimidazole moiety resulting in improved solubility while maintaining picomolar potency [5 (KLCA4); IC{sub 50} = 305 pM]. With exceptional solubility, this finding has potential for improving PK to help diagnose and treat lymphomas.

  15. Comparative study on dry etching of alpha- and beta-SiC nano-pillars

    Choi, J. H.; Latu-Romain, L.; Bano, E; Henry, Anne; Lee, W J; Chevolleau, T; Baron, T.


    Different polytypes (alpha-SiC and beta-SiC) and crystallographic orientations ((0001) and (11-20) of 6H-SiC) have been used in order to elaborate silicon carbide (SiC) nanopillars using the inductively coupled plasma etching method. The cross section of the SiC pillars shows a rhombus, pentagonal or hexagonal morphology depending on polytypes and crystallographic orientations. The favored morphologies of SiC nanopillars originate from a complex interplay between their polytypes and crystal o...

  16. A bar-code reader for an alpha-beta automatic counting system - FAG

    A bar-code laser system for sample number reading was integrated into the FAG Alpha-Beta automatic counting system. The sample identification by means of an attached bar-code label enables unmistakable and reliable attribution of results to the counted sample. Installation of the bar-code reader system required several modifications: Mechanical changes in the automatic sample changer, design and production of new sample holders, modification of the sample planchettes, changes in the electronic system, update of the operating software of the system (authors)

  17. Antimicrobial actions of the human epididymis 2 (HE2 protein isoforms, HE2alpha, HE2beta1 and HE2beta2

    French Frank S


    Full Text Available Abstract Background The HE2 gene encodes a group of isoforms with similarities to the antimicrobial beta-defensins. We demonstrated earlier that the antimicrobial activity of HE2 proteins and peptides is salt resistant and structure dependent and involves permeabilization of bacterial membranes. In this study, we further characterize the antimicrobial properties of HE2 peptides in terms of the structural changes induced in E. coli and the inhibition of macromolecular synthesis. Methods E. coli treated with 50 micro g/ml of HE2alpha, HE2beta1 or HE2beta2 peptides for 30 and 60 min were visualized using transmission and scanning electron microscopy to investigate the impact of these peptides on bacterial internal and external structure. The effects of HE2alpha, HE2beta1 and HE2beta2 on E. coli macromolecular synthesis was assayed by incubating the bacteria with 2, 10 and 25 micro g/ml of the individual peptides for 0–60 min and measuring the incorporation of the radioactive precursors [methyl-3H]thymidine, [5-3H]uridine and L-[4,5-3H(N]leucine into DNA, RNA and protein. Statistical analyses using Student's t-test were performed using Sigma Plot software. Values shown are Mean ± S.D. Results E. coli treated with HE2alpha, HE2beta1 and HE2beta2 peptides as visualized by transmission electron microscopy showed extensive damage characterized by membrane blebbing, thickening of the membrane, highly granulated cytoplasm and appearance of vacuoles in contrast to the smooth and continuous membrane structure of the untreated bacteria. Similarly, bacteria observed by scanning electron microscopy after treating with HE2alpha, HE2beta1 or HE2beta2 peptides exhibited membrane blebbing and wrinkling, leakage of cellular contents, especially at the dividing septa, and external accumulation of fibrous materials. In addition, HE2alpha, HE2beta1 and HE2beta2 peptides inhibited E. coli DNA, RNA and protein synthesis. Conclusions The morphological changes observed

  18. Artemia hemoglobins. Increase in net synthesis of the beta-polypeptide (relative to the alpha-polypeptide) in hypoxia.

    Ferry, J A; Nichols, R C; Condon, S J; Stubbs, J D; Bowen, S T


    Previous studies have shown that in the brine shrimp there are three dimeric hemoglobins with polypeptide composition alpha 2, alpha beta, beta 2. Concentrations of the alpha- and beta-polypeptides increase in hypoxia. We now report a two-dimensional electrophoretic method for assay of radiolabelled polypeptides in each hemoglobin. Net synthesis (synthesis minus degradation) of the beta-chain, relative to that of the alpha-chain, increases more than 3-fold (in male and female adults) within 3 days following a downshift in oxygen concentration from 0.2 to 0.1 mM in the culture medium. 3 days after downshift (2 days after in vivo incorporation of radiolabelled leucine), the beta-homodimer contained 10-20% of the radiolabel in the three hemoglobins although beta 2 was usually not detectable in the protein stain of an overloaded gel. The amount of radioactive leucine incorporated per unit amount of protein was more than 300-times greater in the beta 2 homodimer than in the beta-subunit of the heterodimer, suggesting that beta 2 does not dissociate rapidly during electrophoresis on the first dimension non-denaturing gel. This evidence for stable association of the two beta-monomers and the 5-8 heme-binding domains within each monomer (in vivo and during electrophoresis on non-denaturing gels) allows us to exclude one of two alternative interpretations of genetic data published previously. We present an independent line of evidence for the dimer model of the native hemoglobins (which states that each polypeptide has many heme-binding domains). PMID:6830806

  19. Tyrosine dephosphorylation of nuclear proteins mimics transforming growth factor beta 1 stimulation of alpha 2(I) collagen gene expression.

    Greenwel, P; Hu, W.; Kohanski, R A; Ramirez, F.


    Transforming growth factor beta 1 (TGF-beta 1) exerts a positive effect on the transcription of genes coding for several extracellular matrix-related products, including collagen I. We have previously identified a strong TGF-beta 1-responsive element (TbRE) in the upstream promoter sequence of the alpha 2(I) collagen (COL1A2) gene. Our experiments have shown that TGF-beta 1 stimulates COL1A2 transcription by increasing binding of an Sp1-containing complex (TbRC) to the TbRE. They have also su...

  20. Crystal Structure of Homoserine Transacetylase from Haemophilus Influenzae Reveals a New Family of alpha/beta-Hydrolases

    Mirza,I.; Nazi, I.; Korczynska, M.; Wright, G.; Berghuis, A.


    Homoserine transacetylase catalyzes one of the required steps in the biosynthesis of methionine in fungi and several bacteria. We have determined the crystal structure of homoserine transacetylase from Haemophilus influenzae to a resolution of 1.65 A. The structure identifies this enzyme to be a member of the alpha/beta-hydrolase structural superfamily. The active site of the enzyme is located near the end of a deep tunnel formed by the juxtaposition of two domains and incorporates a catalytic triad involving Ser143, His337, and Asp304. A structural basis is given for the observed double displacement kinetic mechanism of homoserine transacetylase. Furthermore, the properties of the tunnel provide a rationale for how homoserine transacetylase catalyzes a transferase reaction vs. hydrolysis, despite extensive similarity in active site architecture to hydrolytic enzymes.

  1. Relationship of endotoxin to tumor necrosis factor-alpha and interleukin-1 beta in children with otitis media with effusion.

    Willett, D N; Rezaee, R P; Billy, J M; Tighe, M B; DeMaria, T F


    Sixty-five middle ear effusions and paired sera from 41 children with chronic otitis media with effusion were assayed for endotoxin and for tumor necrosis factor alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) in order to establish whether a correlation exists between the concentrations of endotoxin and of these cytokines. Endotoxin concentration was determined by means of a chromogenic limulus amebocyte lysate assay, and the cytokine concentration by means of a quantitative enzyme-linked immunosorbent assay. Forty percent of the effusions had detectable levels of endotoxin, with a mean concentration of 2.9 +/- 7.8 endotoxin units per milligram of total protein. The mean concentration of TNF-alpha was 1.24 +/- 3.1 pg/mg total protein, and that of IL-1 beta was 18.79 pg/mg total protein. A strong, statistically significant correlation exists between the concentrations of endotoxin and TNF-alpha (r = .89) and IL-1 beta (r = .72). The data indicate that endotoxin may contribute to the pathogenesis of chronic otitis media with effusion by stimulating the sustained production of TNF-alpha and IL-1 beta in the middle ear. PMID:9439385

  2. Measles virus infection enhances IL-1 beta but reduces tumor necrosis factor-alpha expression in human monocytes.

    Leopardi, R; Vainionpää, R; Hurme, M; Siljander, P; Salmi, A A


    Monocytes may play a role in the immunologic abnormalities caused by measles. The effect of measles virus (MV) infection on peripheral blood monocyte functions is poorly known. We report that MV-infected PBM have an altered pattern of IL-1 beta and TNF-alpha production in response to stimulation with LPS and PMA in vitro. MV-infected peripheral blood monocytes produced higher amounts of IL-1 beta, whereas the production of TNF-alpha was reduced. The same effect was observed in the human monocytic cell line THP-1, which was used for RNA analysis. An increased steady-state level of IL-1 beta mRNA was observed in MV-infected cells, and the level of TNF-alpha mRNA was reduced. However, both IL-1 beta and TNF-alpha had about 50% increased transcription rate. Analysis of the mRNA stability after transcriptional block by actinomycin D showed that the TNF-alpha mRNA had a reduced half-life in MV-infected cells (about 30 vs 80 min in uninfected cells), whereas IL-1 beta mRNA stability was similar in uninfected and MV-infected cells. These results indicate that MV infection disturbs the immunoregulatory network by interfering with the monocyte functions. PMID:1527385

  3. Alpha- and beta-adrenergic-receptor systems in bronchial asthma and in subjects without asthma: reduced mononuclear cell beta-receptors in bronchial asthma.

    Sato, T; Bewtra, A K; Hopp, R J; Nair, N; Townley, R G


    We assessed the adrenergic-receptor system in individuals with bronchial hyperreactivity, beta-Adrenergic receptors on mononuclear cell membranes, alpha-adrenergic receptors on platelet membranes, and the cAMP response in these cell types to different stimuli, including platelet-activating factor (PAF), were determined. Studies were assessed in 10 subjects with mild asthma, six methacholine-sensitive subjects without asthma, and 10 normal subjects. The density and affinity of beta-receptors and alpha-receptors were determined by Scatchard analysis. Our findings were that (1) subjects with asthma had a significantly lower density of beta-receptors compared to normal subjects, (2) subjects with asthma had a significantly lower cAMP response to isoproterenol stimulation compared to the two other groups, (3) in subjects without asthma. PAF decreased the basal cAMP level and significantly inhibited the response to isoproterenol stimulation, (4) there was no difference in density and affinity of platelet alpha-receptors or in platelet cAMP responses to stimulation by alpha-agonists among these three groups, and (5) neither cAMP response or beta-receptor density on mononuclear cells were significantly correlated with pulmonary-function tests (FEV/FVC times 100), sensitivity to methacholine, or cold-air inhalation. These results suggest that patients with asthma may have a lower isoproterenol cAMP response and decreased density of beta-adrenergic receptors on mononuclear cells in the absence of beta-agonist therapy. It is speculated that release of PAF and other mediators secondary to allergen exposure, even in the absence of overt attacks of asthma, may inhibit the response to endogenous or exogenous beta-adrenergic agonists. PMID:2175758

  4. Antimigratory effect of TK1-2 is mediated in part by interfering with integrin alpha2beta1.

    Kim, Hyun-Kyung; Oh, Dae-Shik; Lee, Sang-Bae; Ha, Jung-Min; Joe, Young Ae


    The recombinant two kringle domain of human tissue-type plasminogen activator (TK1-2) has been shown to inhibit endothelial cell proliferation, angiogenesis, and tumor cell growth despite of sharing a low amino acid sequence homology with angiostatin. Here, we explored a possible inhibitory mechanism of action of TK1-2 by focusing on antimigratory effect. TK1-2 effectively inhibited endothelial cell migration induced by basic fibroblast growth factor or vascular endothelial growth factor in a dose-dependent manner and tube formation on Matrigel. It blocked basic fibroblast growth factor-induced or vascular endothelial growth factor-induced phosphorylation of extracellular signal-regulated kinase 1/2 and formation of actin stress fibers and focal adhesions. Interestingly, TK1-2 alone induced the weak phosphorylation of focal adhesion kinase, whereas it inhibited focal adhesion kinase phosphorylation induced by growth factors. When immobilized, TK1-2 promoted adhesion and spreading of endothelial cells compared with bovine serum albumin. However, treatment with anti-alpha(2)beta(1) blocking antibody markedly diminished endothelial cell adhesion to immobilized TK1-2 compared with anti-alpha(v)beta(3) or anti-alpha(5)beta(1) antibody. Pretreatment of soluble TK1-2 also altered the binding level of anti-alpha(2)beta(1) antibody to endothelial cells in fluorescence-activated cell sorting analysis. Indeed, a blocking antibody against integrin alpha(2)beta(1) or knocking down of integrin alpha(2) expression prevented the inhibitory effect of TK1-2 in cell migration. Therefore, these results suggest that TK1-2 inhibits endothelial cell migration through inhibition of signaling and cytoskeleton rearrangement in part by interfering with integrin alpha(2)beta(1). PMID:18645023

  5. Placental transfer and metabolism of 17 alpha-ethynylestradiol-17 beta and estradiol-17 beta in the rhesus monkey

    The synthetic estrogen component of many oral contraceptives, 17 alpha-ethynylestradiol-17 beta (EE2) and the naturally occurring estrogen, estradiol-17 beta (E2) were studied in four pregnant rhesus monkeys (71% term: 108-121 days gestational age). Under ketamine anesthesia, catheters were implanted in the maternal femoral artery and fetal interplacental artery. After simultaneous i.v. administration of [3H]EE2-[14C]E2 to the maternal animal, serial blood samples were drawn from both mother and fetus. The estrogens and metabolites were identified and quantified by the comigration of radioactivity with reference standards in several high-performance liquid chromatography systems and subsequent selective enzyme hydrolysis of the conjugates. Only estrone (E1), E1 sulfate, EE2 and EE2-3 sulfate were observed in the fetal circulation, whereas the major radiolabeled compounds in the maternal circulation consisted of the above plus E2, E1 glucuronide and EE2-3 glucuronide. In order to determine whether the placenta could convert E2 to its metabolite E1, the placentas of three term rhesus monkeys were perfused in situ via the umbilical artery with 120 ml (15 ml/min) of Hanks' balanced salt solution (pH 7.4) containing [3H]E2. High-performance liquid chromatographic analysis of umbilical vein samples revealed that 96% of the E2 was metabolized to E1. These studies indicate that the placenta can metabolize the potent naturally occurring estrogen E2 to the less potent E1. In contrast, the synthetic estrogen EE2 does not undergo this placental metabolic conversion and thus enters the fetal circulation as the parent compound




    We have characterized the structural abnormality of a new alpha chain mutant found in a Kurdish; family. The clinical and hematological investigation of eight individuals have shown that the a variant is associated with a beta degrees-thalassemia mutation (nonsense codon 39). The tryptic peptide map

  7. Metastatic dissemination of human ovarian epithelial carcinoma is promoted by alpha2beta1-integrin-mediated interaction with type I collagen.

    Fishman, D A; Kearns, A; Chilukuri, K; Bafetti, L M; O'Toole, E A; Georgacopoulos, J; Ravosa, M J; Stack, M S


    Metastatic dissemination of epithelial ovarian carcinoma is thought to be mediated via tumor cell exfoliation into the peritoneal cavity, followed by adhesion to and invasion through the mesothelium which overlies the contents of the peritoneal cavity. In this study, we have utilized short-term primary cultures to analyze the effect of specific extracellular matrix proteins on properties of human ovarian epithelial carcinoma cells which contribute to the invasive phenotype. Analysis of cell:matrix adhesive profiles indicated that ovarian carcinoma cells adhere preferentially to type I collagen. Immunoprecipitation analyses demonstrated the presence of the collagen-binding alpha2beta1 integrin in biotin-labeled ovarian carcinoma cell membranes, and cellular adhesion was inhibited by blocking antibodies directed against the alpha2 and beta1 integrin subunits. The alpha2beta1-binding peptide Asp-Gly-Glu-Ala (DGEA) was also moderately effective at blocking adhesion to collagen relative to the control peptide Ala-Gly-Glu-Ala (AGEA). Analysis of cell motility on protein-coated colloidal gold coverslips demonstrated that ovarian carcinoma cells migrate preferentially on type I collagen coated surfaces. Type I collagen promoted migration in a concentration-dependent, saturable manner, with maximal migration observed at a collagen-coating concentration of 50 microg/ml. Migration on collagen was inhibited by antibodies directed against the alpha2 and beta1 integrin subunits and by DGEA peptide, providing evidence for the role of the alpha2beta1 integrin in ovarian carcinoma cell motility. Culturing ovarian carcinoma cells on type I collagen gels led to a significant increase in conversion of the matrix metalloproteinase 2 zymogen to the 66-kD form, suggesting that adhesion to collagen also influences matrix-degrading proteinases. These data suggest that alpha2beta1-integrin-mediated interaction of ovarian carcinoma cells with type I collagen, a protein prevalent both in the

  8. Noradrenergic modulation of basolateral amygdala neuronal activity: opposing influences of alpha-2 and beta receptor activation.

    Buffalari, Deanne M; Grace, Anthony A


    Substantial data exists demonstrating the importance of the amygdala and the locus ceruleus (LC) in responding to stress, aversive memory formation, and the development of stress-related disorders; however, little is known about the effects of norepinephrine (NE) on amygdala neuronal activity in vivo. The basolateral nucleus of the amygdala (BLA) receives dense NE projections from the LC, NE increases in the BLA in response to stress, and the BLA can also modulate the LC via reciprocal projections. These experiments examined the effects of noradrenergic agents on spontaneous and evoked responses of BLA neurons. NE iontophoresis inhibited spontaneous firing and decreased the responsiveness of BLA neurons to electrical stimulation of entorhinal cortex and sensory association cortex (Te3). Confirmed BLA projection neurons exhibited exclusively inhibitory responses to NE. Systemic administration of propranolol, a beta-receptor antagonist, decreased the spontaneous firing rate and potentiated the NE-evoked inhibition of BLA neurons. In addition, iontophoresis of the alpha-2 agonist clonidine, footshock administration, and LC stimulation mimicked the effects of NE iontophoresis on spontaneous activity. Furthermore, the effects of LC stimulation were partially blocked by systemic administration of alpha 2 and beta receptor antagonists. This is the first study to demonstrate the actions of directly applied and stimulus-evoked NE in the BLA in vivo, and provides a mechanism by which beta receptors can mediate the important behavioral consequences of NE within the BLA. The interaction between these two structures is particularly relevant with regard to their known involvement in stress responses and stress-related disorders. PMID:17989300

  9. Rapid and simultaneous detection of alpha/beta radioactivity in food by solid phase extraction liquid scintillation counting

    The purpose of this study was to develop a practical radioanalytical method suitable for screening for beta- and alpha-emitting radioactive contamination in a large number and wide variety of foods in the event of a nuclear or radiological emergency. Simple and rapid solid-phase extraction was used to overcome matrix and radiometric interferences that occurred during food analysis. Benefiting from discriminative liquid scintillation counting, simultaneous detection of alpha and beta radioactivity was achieved with negligible quench effects and ∼95 % counting efficiencies. Method limits of detection were ∼0.06 Bq/kg for alpha and ∼0.4 Bq/kg for beta radioactivity and the results were within ±20 % of the known values. (author)

  10. Modelling of the partial oxidation of {alpha}, {beta}-unsaturated aldehydes on Mo-V-oxides based catalysts

    Boehnke, H.; Petzoldt, J.C.; Stein, B.; Weimer, C.; Gaube, J.W. [Technische Univ. Darmstadt (Germany). Inst. fuer Chemische Technologie


    A kinetic model based on the Mars-van Krevelen mechanism that allows to describe the microkinetics of the heterogeneously catalysed partial oxidation of {alpha}, {beta}-unsaturated aldehydes is presented. This conversion is represented by a network, composed of the oxidation of the {alpha}, {beta}-unsaturated aldehyde towards the {alpha}, {beta}-unsaturated carboxylic acid and the consecutive oxidation of the acid as well as the parallel reaction of the aldehyde to products of deeper oxidation. The reaction steps of aldehyde respectively acid oxidation and catalyst reoxidation have been investigated separately in transient experiments. The combination of steady state and transient experiments has led to an improved understanding of the interaction of the catalyst with the aldehyde and the carboxylic acids as well as to a support of the kinetic model assumptions. (orig.)