Non-resonant triple alpha reaction rate at low temperature

Energy Technology Data Exchange (ETDEWEB)

Itoh, T.; Tamii, A.; Aoi, N.; Fujita, H.; Hashimoto, T.; Miki, K.; Ogata, K. [Research Center for Nuclear Physics, Osaka University, Ibaraki, Osaka 567-0047 (Japan); Carter, J.; Donaldson, L.; Sideras-Haddad, E. [Schools of Physics, University of Witwatersrand, Johannesburg 2050 (South Africa); Furuno, T.; Kawabata, T. [Departments of Physics, Kyoto University, Sakyo, Kyoto, 606-8502 (Japan); Kamimura, M. [RIKEN Nishina Center, Wako, Saitama, 351-0198 (Japan); Nemulodi, F.; Neveling, R.; Smit, F. D.; Swarts, C. [iThemba Laboratory for Accelerator Based Sciences Somerset, West, 7129 (South Africa)

2014-05-02

Our experimental goal is to study the non-resonant triple alpha reaction rate at low temperture (T < 10{sup 8} K). The {sup 13}C(p,d) reaction at 66 MeV has been used to probe the alpha-unbound continuum state in {sup 12}C just below the 2{sup nd} 0{sup +} state at 7.65 MeV. The transition strength to the continuum state is predicted to be sensitive to the non-resonant triple alpha reaction rate. The experiment has been performed at iThemba LABS. We report the present status of the experiment.

FcepsilonRI-alpha siRNA inhibits the antigen-induced activation of mast cells.

Science.gov (United States)

Safaralizadeh, Reza; Soheili, Zahra-Soheila; Deezagi, Abdolkhaleg; Pourpak, Zahra; Samiei, Shahram; Moin, Mostafa

2009-12-01

FcepsilonRI, The high affinity receptor for IgE plays a critical role in triggering the allergic reactions. It is responsible for inducing mast cell degranulation and deliberation of allergy mediators when it is aggregated by allergen and IgE complexes. FcepsilonRI on the mast cells consists of three subunits; alpha chain directly binds IgE, beta chain and dimmer of gamma chains together mediate intracellular signaling. Cross-linking of IgE-bound FcepsilonRI on the surface of mast cells and basophils by the multivalent antigen induces release of chemical mediators. The present in vitro study was designed to investigate the effect of synthetic FcepsilonRI-alpha siRNA on the antigen-induced activation of MC/9 cells. MC/9 cells which are murine mast cells were transfected by FcepsilonRI-alpha siRNA and negative control siRNA. After 6 h, anti-DNP (Dinitrophenyl) IgE was used for the cells sensitization. Then the cells were challenged with Dinitrophenyl-Human Serum Albumin (DNP-HSA) for mast cell degranulation induction before collection of supernatants. The amount of mRNA and protein expression was measured by Real Time PCR and western blot analysis, respectively. Determination of the expression rate of FcepsilonRI-alpha on cell surface was achieved by flow cytometry. ELISA and spectrophotometry methods were used subsequently for measuring the effects of FcepsilonRI-alpha siRNA on antigen-induced histamine and beta-hexosaminidase release. FcepsilonRI-alpha siRNA treated cells showed significant decrease in FcepsilonRI-alpha mRNA and protein expression in comparison to control cells. FcepsilonRI-mediated mast cell release of beta-hexosaminidase and histamine were also inhibited. In this study it was shown that FcepsilonRI-alpha siRNA could suppress FcepsilonRI-alpha expression and inhibited degranulation and histamine release in antigen-stimulated MC/9 cells. In conclusion, knock-down of FcepsilonRI-alpha by siRNA could be a promising method for inhibition of the mast

Leptin potentiates Prevotella intermedia lipopolysaccharide-induced production of TNF-alpha in monocyte-derived macrophages.

Science.gov (United States)

Kim, Sung-Jo

2010-06-01

In addition to regulating body weight, leptin is also recognized for its role in the regulation of immune function and inflammation. The purpose of this study was to investigate the effect of leptin on Prevotella (P.) intermedia lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-alpha production in differentiated THP-1 cells, a human monocytic cell line. LPS from P. intermedia ATCC 25611 was prepared by the standard hot phenol-water method. THP-1 cells were incubated in the medium supplemented with phorbol myristate acetate to induce differentiation into macrophage-like cells. The amount of TNF-alpha and interleukin-8 secreted into the culture medium was determined by enzyme-linked immunosorbent assay (ELISA). TNF-alpha and Ob-R mRNA expression levels were determined by semi-quantitative reverse transcription-polymerase chain reaction analysis. Leptin enhanced P. intermedia LPS-induced TNF-alpha production in a dose-dependent manner. Leptin modulated P. intermedia LPS-induced TNF-alpha expression predominantly at the transcriptional level. Effect of leptin on P. intermedia LPS-induced TNF-alpha production was not mediated by the leptin receptor. The ability of leptin to enhance P. intermedia LPS-induced TNF-alpha production may be important in the establishment of chronic lesion accompanied by osseous tissue destruction observed in inflammatory periodontal disease.

Study of ({alpha}, {sup 3}He) and ({alpha}, t) reactions on {sup 28}Si at 45 MeV

Energy Technology Data Exchange (ETDEWEB)

Darshan, V.P.; Sathyavathiamma, M.P.; Ramaswamy, C.R.; Raja Rao, M.; Puttaswamy, N.G.; Banerjee, S.R.; Chintalapudi, S.N. [Dept. of Phys., Bangalore Univ. (India)

1995-03-01

The {sup 28}Si({alpha}, {sup 3}He){sup 29}Si, {sup 28}Si({alpha}, t){sup 29}P and Si({alpha}, {alpha})Si reactions were studied at E{sub {alpha}} = 45 MeV. Exact finite-range (EFR) DWBA analysis was carried out for the transitions to the ground state and to five excited states in {sup 29}Si and {sup 29}P. Spectroscopic strengths G were extracted for all the states and were compared with the predictions from shell-model and quasi-particle core-coupling calculations. Similar EFR-DWBA analyses were carried out from available (unpublished) data for the {sup 28}Si({alpha}, {sup 3}He){sup 29}Si reaction at E{sub {alpha}} = 64.9 and 120 MeV, and for the {sup 28}Si({alpha}, t){sup 29}P reaction at E{sub {alpha}} = 50 and 64.9 MeV. The comparison of experimental and theoretical values of G are provided. (author)

Flavonoids-induced accumulation of hypoxia-inducible factor (HIF)-1alpha/2alpha is mediated through chelation of iron.

Science.gov (United States)

Park, Sung-Soo; Bae, Insoo; Lee, Yong J

2008-04-15

Hypoxia-inducible factor-1 alpha (HIF-1alpha) is the regulatory subunit of the heterodimeric transcription factor HIF-1 that is the key regulator of cellular response to low oxygen tension. Under normoxic conditions, HIF-1alpha is continuously degraded by the ubiquitin-proteasome pathway through pVHL (von Hippel-Lindau tumor suppressor protein). Under hypoxic conditions, HIF-1alpha is stabilized and induces the transcription of HIF-1 target genes. Quercetin, a flavonoid with anti-oxidant, anti-inflammatory, and kinase modulating properties, has been found to induce HIF-1alpha accumulation and VEGF secretion in normoxia. In this study, the molecular mechanisms of quercetin-mediated HIF-1alpha accumulation were investigated. Previous studies have shown that, in addition to being induced by hypoxia, HIF-1alpha can be induced through the phosphatidylinositol 3-kinase (PI3K)/Akt and p53 signaling pathways. But our study revealed, through p53 mutant-type as well as p53 null cell lines, that neither the PI3K/Akt nor the p53 signaling pathway is required for quercetin-induced HIF-1alpha accumulation. And we observed that HIF-1alpha accumulated by quercetin is not ubiquitinated and the interaction of HIF-1alpha with pVHL is reduced, compared with HIF-1alpha accumulated by the proteasome inhibitor MG132. The use of quercetin's analogues showed that only quercetin and galangin induce HIF-1/2alpha accumulation and this effect is completely reversed by additional iron ions. This is because quercetin and galangin are able to chelate cellular iron ions that are cofactors of HIF-1/2alpha proline hydroxylase (PHD). These data suggest that quercetin inhibits the ubiquitination of HIF-1/2alpha in normoxia by hindering PHD through chelating iron ions.

Study of transfer reactions ({alpha},t), ({alpha},{sup 3}He) in the f-p shell: mechanism and spectroscopic use; Etude des reactions de transfert ({alpha},t), ({alpha},{sup 3}He) dans la couche f-p mecanisme et utilisation spectroscopique

Energy Technology Data Exchange (ETDEWEB)

Roussel, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1968-05-01

We describe an experimental study of ({alpha},t), ({alpha},{sup 3}He) reactions at 44 MeV using a solid-state identifier, on the target-nuclei {sup 54}Fe and {sup 58,60,62,64}Ni. A critical study of optical model and of disturbed wave analysis has been performed. We show the complementarity of different transfer-reactions, the ambiguity of spectroscopic factors, the importance of the problem of the reaction mechanism. (author) [French] On decrit une etude experimentale des reactions ({alpha},t), ({alpha},{sup 3}He) a 44 MeV utilisant un systeme identificateur de particules sur les noyaux-cibles {sup 54}Fe et {sup 58,60,62,64}Ni. Une etude critique de modele optique et d'analyse en ondes deformees (D.W.B.A.) a ete entreprise. On montre la complementarite des differentes reactions de transfert, l'ambiguite des facteurs spectroscopiques, l'importance du probleme du mecanisme. (auteur)

Laboratory investigations of the alpha-pinene/ozone gas-phase reaction

International Nuclear Information System (INIS)

Benner, C.L.

1985-01-01

In order to provide more insight into terpene photooxidation or ozonolysis reaction mechanisms, a radiotracer technique was developed. This technique was applied to an investigation of the 14 C-alpha-pinene/ozone reaction. In the first phase of the research, the carbon distribution at the conclusion of the ozonolysis reaction was determined by separating carbon-14-labelled gaseous products from labelled aerosols, and counting each phase by liquid scintillation methods. The resulting carbon balance was 38% to 60% filtered aerosols, 6% to 20% gas phase compounds, and 11% to 29% products absorbed on the reaction chamber walls. Recoveries of the alpha-pinene carbon-14 ranging from 79% to 97% were achieved using this method. The alpha-pinene concentrations in these experiments were close to ambient (1 part per billion), yet the carbon balance was similar to that observed at much higher concentrations (>1 part per million). In the second phase of the alpha-pinene study, both gas and aerosol products of the ozonolysis reaction were collected on cartridges impregnated with 2,4-dinitrophenylhydrazine, then analyzed by HPLC. In the final experiments, alpha-pinene aerosol was reacted with a silylating agent to improve the detection of organic acids and alcohols. The gas chromatographic/mass spectrometric analysis of the silylated aerosol products showed evidence of dimer/polymer formation occurring in the ozonolysis reaction

Application of multi-step direct reaction theory to 14 MeV neutron reaction, 3 (n,. cap alpha. )

Energy Technology Data Exchange (ETDEWEB)

Kumabe, I.; Matoba, M.; Fukuda, K. [Kyushu Univ., Fukuoka (Japan). Faculty of Engineering; Ikegami, H.; Muraoka, M [eds.

1980-01-01

Multi-step direct-reaction theory proposed by Tamura et al. has been applied to continuous spectra of the 14 MeV (n, ..cap alpha..) reaction with some modifications. Calculated results reproduce well the experimental energy and angular distributions of the 14 MeV (n, ..cap alpha..) reactions.

Breakout from the hot CNO cycle: the {sup 15}O({alpha},{gamma}) and {sup 18}Ne({alpha},p) reactions

Energy Technology Data Exchange (ETDEWEB)

Bradfield-Smith, W; Laird, A M; Davinson, T; Pietro, A di; Ostrowski, A N; Shotter, A C; Woods, P J [Dept. of Physics and Astronomy, Univ. of Edinburgh (United Kingdom); Cherubini, S; Galster, W; Graulich, J S; Leleux, P; Michel, L; Ninane, A; Vervier, J [Inst. de Physique Nucleaire, UCL, Louvain-la-Neuve (Belgium); Aliotta, M; Cali, D; Cappussello, F; Cunsolo, A; Spitaleri, C [INFN, Catania (Italy); Gorres, J; Wiescher, M [Notre Dame Univ. (United States); Rahighi, J [Van de Graaf Lab., Tehran (Iran, Islamic Republic of); Hinnefeld, J [Indiana Univ., South Bend (United States)

1998-06-01

One of the most important reactions which determines the rate of breakout from the hot CNO cycle is the {sup 15}O({alpha},{gamma}){sup 19}Ne. The reaction {sup 18}Ne({alpha},p){sup 21}Na may also provide an alternative breakout route. Experiments are being undertaken at Louvain-La-Neuve using the radioactive {sup 18}Ne beam to study these reactions by measurement of {alpha}({sup 18}Ne,p){sup 21}Na and d({sup 18}Ne,p){sup 19}Ne{sup *} {yields} {sup 15}O + {alpha} (orig.)

Alpha-decay within Feshbach theory of nuclear reactions

International Nuclear Information System (INIS)

Sandulescu, A.; Silisteanu, I.; Wunsch, R.

1977-01-01

In the frame of Feshbach theory of nuclear reactions the alpha-decay widths are determined by the alpha-daughter nucleus optical potential and by the formation factors. It is shown that the calculated absolute values of the alpha widths for Po light isotopes are in good agreement with experimental data, if the real part of the optical potential with the parameters fitted by the low energy α-scattering is used

Determination by transfer reaction of alpha widths in fluorine for astrophysical interest; Determination par reaction de transfert de largeurs alpha dans le fluor 19. Applications a l'astrophysique

Energy Technology Data Exchange (ETDEWEB)

Oliveira Santos, F de

1995-04-15

The nucleosynthesis of fluorine is not known. Several astrophysical models predict the alpha radiative capture onto N{sup 15} as the main fluorine production reaction. In the expression of the reaction rate, one parameter is missing: the alpha width of the resonance on the E = 4.377 MeV level in fluorine. A direct measurement is excluded due to the very low cross-section expected. We have determined this alpha width using a transfer reaction followed by analyses with FR-DWBA (Finite Range Distorted Wave Born Approximation) in a simple cluster alpha model. This experiment was carried out with a Li{sup 7} beam with E = 28 MeV onto a N{sup 15} gas target. The 16 first levels were studied. Spectroscopic factors were extracted for most of them. Alpha widths for unbound levels were determined. Many alpha width were compared with known values from direct reaction and the differences lie within the uncertainty range (factor 2). The alpha width for the E = 4.377 MeV level was determined ({gamma}{sub {alpha}} = 1.5*10{sup -15} MeV), its value is about 60 times weaker than the used value. The influence of our new rate was studied in AGB (Asymptotic Giant Branch) stars during thermal pulses. In this model the alteration is sensitive. (author)

Investigation of activation cross-sections of alpha-induced nuclear reactions on natural cadmium

Energy Technology Data Exchange (ETDEWEB)

Khandaker, Mayeen Uddin [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Kim, Kwangsoo [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Lee, Manwoo [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Research Center, Dongnam Institute of Radiological and Medical Science, Busan 619-953 (Korea, Republic of); Kim, Guinyun, E-mail: gnkim@knu.ac.kr [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of)

2014-08-15

We measured production cross-sections of Sn, In, and Cd radionuclides from alpha-induced reactions on {sup nat}Cd from their respective threshold to 45 MeV by using a stacked-foil activation technique at the MC-50 cyclotron of the Korea Institute of Radiological and Medical Sciences. The results were compared with the earlier measurements as well as with the theoretical values obtained from the TENDL-2012 library based on the TALYS 1.4 code. Our measurements for the {sup 110,113g,117m}Sn, {sup 108m,108g,109g,110m,110g,111g,113m,114m,115m,116m,117m,117g}In, and {sup 111m,115g}Cd radionuclides in the energy region from the threshold energy to 45 MeV are in general good agreement with the other experimental data and calculated results. The integral yields for thick target were also deduced using the measured cross-sections and the stopping power of natural cadmium target and found in agreement with the directly measured yields available in the literature. The measured cross-sections find importance in various practical applications including nuclear medicine and improvement of nuclear model calculations.

Determination by transfer reaction of alpha widths in fluorine for astrophysical interest

International Nuclear Information System (INIS)

Oliveira Santos, F. de

1995-04-01

The nucleosynthesis of fluorine is not known. Several astrophysical models predict the alpha radiative capture onto N 15 as the main fluorine production reaction. In the expression of the reaction rate, one parameter is missing: the alpha width of the resonance on the E = 4.377 MeV level in fluorine. A direct measurement is excluded due to the very low cross-section expected. We have determined this alpha width using a transfer reaction followed by analyses with FR-DWBA (Finite Range Distorted Wave Born Approximation) in a simple cluster alpha model. This experiment was carried out with a Li 7 beam with E = 28 MeV onto a N 15 gas target. The 16 first levels were studied. Spectroscopic factors were extracted for most of them. Alpha widths for unbound levels were determined. Many alpha width were compared with known values from direct reaction and the differences lie within the uncertainty range (factor 2). The alpha width for the E = 4.377 MeV level was determined (Γ α = 1.5*10 -15 MeV), its value is about 60 times weaker than the used value. The influence of our new rate was studied in AGB (Asymptotic Giant Branch) stars during thermal pulses. In this model the alteration is sensitive. (author)

Double differential cross-sections of (n,{alpha}) reactions in aluminium and nickel at 14.77 MeV neutrons

Energy Technology Data Exchange (ETDEWEB)

Lalremruata, B.; Dhole, S.D. [Department of Physics, University of Pune, Pune-411007 (India); Ganesan, S. [Reactor Physics Design Division, BARC, Mumbai-400085 (India); Bhoraskar, V.N. [Department of Physics, University of Pune, Pune-411007 (India)], E-mail: vnb@physics.unipune.ernet.in

2009-04-15

The double differential cross-sections (DDX) for the emission of alpha particles from {sup 27}Al(n,{alpha}){sup 24}Na and Ni(n,{alpha}) reactions induced by 14.77 MeV neutrons were estimated from the alpha particle spectra recorded at 30 deg., 50 deg., 90 deg., 110 deg. angles for aluminium, and at 20 deg., 45 deg., 90 deg., 110 deg. for natural nickel. The results indicate that the alpha particles below and around the most probable energies ({approx}6.3 MeV from aluminium and {approx}8 MeV from natural nickel) are emitted predominantly through the compound nucleus formation process, and the higher energy alpha particles are emitted through the pre-equilibrium or the direct reaction. In general, the measured double-differential cross-sections are in agreement with the theoretical cross-sections estimated using Talys-1.0 and Preco2007 computer programs. The present value of the level density parameter for {sup 24}Na is close to the literature value and, therefore, these results reveal consistency in the alpha particle spectra recorded with a single silicon surface barrier detector at different scattering angles.

Determination by transfer reaction of alpha widths in fluorine for astrophysical interest; Determination par reaction de transfert de largeurs alpha dans le fluor 19. Applications a l'astrophysique

Energy Technology Data Exchange (ETDEWEB)

Oliveira Santos, F. de

1995-04-15

The nucleosynthesis of fluorine is not known. Several astrophysical models predict the alpha radiative capture onto N{sup 15} as the main fluorine production reaction. In the expression of the reaction rate, one parameter is missing: the alpha width of the resonance on the E = 4.377 MeV level in fluorine. A direct measurement is excluded due to the very low cross-section expected. We have determined this alpha width using a transfer reaction followed by analyses with FR-DWBA (Finite Range Distorted Wave Born Approximation) in a simple cluster alpha model. This experiment was carried out with a Li{sup 7} beam with E = 28 MeV onto a N{sup 15} gas target. The 16 first levels were studied. Spectroscopic factors were extracted for most of them. Alpha widths for unbound levels were determined. Many alpha width were compared with known values from direct reaction and the differences lie within the uncertainty range (factor 2). The alpha width for the E = 4.377 MeV level was determined ({gamma}{sub {alpha}} = 1.5*10{sup -15} MeV), its value is about 60 times weaker than the used value. The influence of our new rate was studied in AGB (Asymptotic Giant Branch) stars during thermal pulses. In this model the alteration is sensitive. (author)

SCALP: Scintillating ionization chamber for ALPha particle production in neutron induced reactions

Science.gov (United States)

Galhaut, B.; Durand, D.; Lecolley, F. R.; Ledoux, X.; Lehaut, G.; Manduci, L.; Mary, P.

2017-09-01

The SCALP collaboration has the ambition to build a scintillating ionization chamber in order to study and measure the cross section of the α-particle production in neutron induced reactions. More specifically on 16O and 19F targets. Using the deposited energy (ionization) and the time of flight measurement (scintillation) with a great accuracy, all the nuclear reaction taking part on this project will be identify.

Analysis of charged particle induced reactions for beam monitor applications

Energy Technology Data Exchange (ETDEWEB)

Surendra Babu, K. [IOP, Academia Sinica, Taipe, Taiwan (China); Lee, Young-Ouk [Nuclear Data Evaluation Laboratory, Korea Atomic Energy Research Institute (Korea, Republic of); Mukherjee, S., E-mail: smukherjee_msuphy@yahoo.co.in [Department of Physics, Faculty of Science, M.S. University of Baroda, Vadodara 390 002 (India)

2012-07-15

The reaction cross sections for different residual nuclides produced in the charged particle (p, d, {sup 3}He and {alpha}) induced reactions were calculated and compared with the existing experimental data which are important for beam monitoring and medical diagnostic applications. A detailed literature compilation and comparison were made on the available data sets for the above reactions. These calculations were carried out using the statistical model code TALYS up to 100 MeV, which contains Kalbach's latest systematic for the emission of complex particles and complex particle-induced reactions. All optical model calculations were performed by ECIS-03, which is built into TALYS. The level density, optical model potential parameters were adjusted to get the better description of experimental data. Various pre-equilibrium models were used in the present calculations with default parameters.

Quercetin suppresses hypoxia-induced accumulation of hypoxia-inducible factor-1alpha (HIF-1alpha) through inhibiting protein synthesis.

Science.gov (United States)

Lee, Dae-Hee; Lee, Yong J

2008-10-01

Quercetin, a ubiquitous bioactive plant flavonoid, has been shown to inhibit the proliferation of cancer cells and induce the accumulation of hypoxia-inducible factor-1alpha (HIF-1alpha) in normoxia. In this study, under hypoxic conditions (1% O(2)), we examined the effect of quercetin on the intracellular level of HIF-1alpha and extracellular level of vascular endothelial growth factor (VEGF) in a variety of human cancer cell lines. Surprisingly, we observed that quercetin suppressed the HIF-1alpha accumulation during hypoxia in human prostate cancer LNCaP, colon cancer CX-1, and breast cancer SkBr3 cells. Quercetin treatment also significantly reduced hypoxia-induced secretion of VEGF. Suppression of HIF-1alpha accumulation during treatment with quercetin in hypoxia was not prevented by treatment with 26S proteasome inhibitor MG132 or PI3K inhibitor LY294002. Interestingly, hypoxia (1% O(2)) in the presence of 100 microM quercetin inhibited protein synthesis by 94% during incubation for 8 h. Significant quercetin concentration-dependent inhibition of protein synthesis and suppression of HIF-1alpha accumulation were observed under hypoxic conditions. Treatment with 100 microM cycloheximide, a protein synthesis inhibitor, replicated the effect of quercetin by inhibiting HIF-1alpha accumulation during hypoxia. These results suggest that suppression of HIF-1alpha accumulation during treatment with quercetin under hypoxic conditions is due to inhibition of protein synthesis. (c) 2008 Wiley-Liss, Inc.

THE RGB AND AGB STAR NUCLEOSYNTHESIS IN LIGHT OF THE RECENT {sup 17}O(p, {alpha}){sup 14}N AND {sup 18}O(p, {alpha}){sup 15}N REACTION-RATE DETERMINATIONS

Energy Technology Data Exchange (ETDEWEB)

Palmerini, S.; Sergi, M. L.; La Cognata, M.; Pizzone, R. G.; Spitaleri, C. [INFN-Laboratori Nazionali del Sud, Catania (Italy); Lamia, L. [Dipartimento di Fisica e Astronomia, Universita di Catania, Catania (Italy)

2013-02-20

In recent years, the Trojan Horse Method (THM) has been used to investigate the low-energy cross sections of proton-induced reactions on A = 17 and A = 18 oxygen isotopes, overcoming extrapolation procedures and enhancement effects due to electron screening. In particular, the strengths of the 20 keV and 65 keV resonances in the {sup 18}O(p, {alpha}){sup 15}N and {sup 17}O(p, {alpha}){sup 14}N reactions, respectively, have been extracted, as well as the contribution of the tail of the broad 656 keV resonance in the {sup 18}O(p, {alpha}){sup 15}N reaction inside the Gamow window. The strength of the 65 keV resonance in the {sup 17}O(p, {alpha}){sup 14}N reaction, measured by means of the THM, has been used to renormalize the corresponding resonance strength in the {sup 17}O + p radiative capture channel. As a result, more accurate reaction rates for the {sup 18}O(p, {alpha}){sup 15}N, {sup 17}O(p, {alpha}){sup 14}N, and {sup 17}O(p, {gamma}){sup 18}F processes have been deduced, devoid of systematic errors due to extrapolation or the electron screening effect. Such rates have been introduced into state-of-the-art red giant branch and asymptotic giant branch (AGB) models for proton-capture nucleosynthesis coupled with extra-mixing episodes. The predicted abundances have been compared with isotopic compositions provided by geochemical analysis of presolar grains. As a result, an improved agreement is found between the models and the isotopic mix of oxide grains of AGB origins, whose composition is the signature of low-temperature proton-capture nucleosynthesis. The low {sup 14}N/{sup 15}N found in SiC grains cannot be explained by the revised nuclear reaction rates and remains a serious problem that has not been satisfactorily addressed.

Measurement of Plutonium-240 Angular Momentum Dependent Fission Probabilities Using the Alpha-Alpha' Reaction

Science.gov (United States)

Koglin, Johnathon

Accurate nuclear reaction data from a few keV to tens of MeV and across the table of nuclides is essential to a number of applications of nuclear physics, including national security, nuclear forensics, nuclear astrophysics, and nuclear energy. Precise determination of (n, f) and neutron capture cross sections for reactions in high- ux environments are particularly important for a proper understanding of nuclear reactor performance and stellar nucleosynthesis. In these extreme environments reactions on short-lived and otherwise difficult-to-produce isotopes play a significant role in system evolution and provide insights into the types of nuclear processes taking place; a detailed understanding of these processes is necessary to properly determine cross sections far from stability. Indirect methods are often attempted to measure cross sections on isotopes that are difficult to separate in a laboratory setting. Using the surrogate approach, the same compound nucleus from the reaction of interest is created through a "surrogate" reaction on a different isotope and the resulting decay is measured. This result is combined with appropriate reaction theory for compound nucleus population, from which the desired cross sections can be inferred. This method has shown promise, but the theoretical framework often lacks necessary experimental data to constrain models. In this work, dual arrays of silicon telescope particle identification detectors and photovoltaic (solar) cell fission fragment detectors have been used to measure the fission probability of the 240Pu(alpha, alpha'f) reaction - a surrogate for the 239Pu(n, f) - and fission of 35.9(2)MeV at eleven scattering angles from 40° to 140° in 10° intervals and at nuclear excitation energies up to 16MeV. Within experimental uncertainty, the maximum fission probability was observed at the neutron separation energy for each alpha scattering angle. Fission probabilities were separated into five 500 keV bins from 5:5MeV to

Recoil-alpha-fission and recoil-alpha-alpha-fission events observed in the reaction Ca-48 + Am-243

NARCIS (Netherlands)

Forsberg, U.; Rudolph, D.; Andersson, L. -L.; Nitto, A. Di; Düllmann, Ch E.; Gates, J. M.; Golubev, P.; Gregorich, K. E.; Gross, C. J.; Herzberg, R. -D.; Hessberger, F. P.; Khuyagbaatar, J.; Kratz, J. V.; Rykaczewski, K.; Sarmiento, L. G.; Schädel, M.; Yakushev, A.; Åberg, S.; Ackermann, D.; Block, M.; Brand, H.; Carlsson, B. G.; Cox, D.; Derkx, X.; Dobaczewski, J.; Eberhardt, K.; Even, J.; Fahlander, C.; Gerl, J.; Jäger, E.; Kindler, B.; Krier, J.; Kojouharov, I.; Kurz, N.; Lommel, B.; Mistry, A.; Mokry, C.; Nazarewicz, W.; Nitsche, H.; Omtvedt, J. P.; Papadakis, P.; Ragnarsson, I.; Runke, J.; Schaffner, H.; Schausten, B.; Shi, Y.; Thörle-Pospiech, P.; Torres, T.; Traut, T.; Trautmann, N.; Türler, A.; Ward, A.; Ward, D. E.; Wiehl, N.

2016-01-01

Products of the fusion-evaporation reaction Ca-48 + Am-243 were studied with the TASISpec set-up at the gas-filled separator TASCA at the GSI Helmholtzzentrum f\\"ur Schwerionenforschung. Amongst the detected thirty correlated alpha-decay chains associated with the production of element Z=115, two

About the reactions sup 3 H(alpha,gamma) sup 7 Li and sup 3 He(alpha,gamma) sup 7 Be

CERN Document Server

Loeffler, W

1993-01-01

In this article the current experimental and theoretical status of the radiative alpha capture reactions sup 3 H(alpha,gamma) sup 7 Li and sup 3 He(alpha,gamma) sup 7 Be and their relations to primordial nucleosynthesis and the solar neutrino problem are reviewed. (author)

Taraxacum officinale induces cytotoxicity through TNF-alpha and IL-1alpha secretion in Hep G2 cells.

Science.gov (United States)

Koo, Hyun-Na; Hong, Seung-Heon; Song, Bong-Keun; Kim, Cheorl-Ho; Yoo, Young-Hyun; Kim, Hyung-Min

2004-01-16

Taraxacum officinale (TO) has been frequently used as a remedy for women's disease (e.g. breast and uterus cancer) and disorders of the liver and gallbladder. Several earlier studies have indicated that TO exhibits anti-tumor properties, but its mechanism remains to be elucidated. In this study, we investigated the effect of TO on the cytotoxicity and production of cytokines in human hepatoma cell line, Hep G2. Our results show that TO decreased the cell viability by 26%, and significantly increased the tumor necrosis factor (TNF)-alpha and interleukin (IL)-1alpha production compared with media control (about 1.6-fold for TNF-alpha, and 2.4-fold for IL-1alpha, P < 0.05). Also, TO strongly induced apoptosis of Hep G2 cells as determined by flow cytometry. Increased amounts of TNF-alpha and IL-1alpha contributed to TO-induced apoptosis. Anti-TNF-alpha and IL-1alpha antibodies almost abolished it. These results suggest that TO induces cytotoxicity through TNF-alpha and IL-1alpha secretion in Hep G2 cells.

Astrophysical reaction rate for the neutron-generator reaction 13C(alpha,n)16O in asymptotic giant branch stars.

Science.gov (United States)

Johnson, E D; Rogachev, G V; Mukhamedzhanov, A M; Baby, L T; Brown, S; Cluff, W T; Crisp, A M; Diffenderfer, E; Goldberg, V Z; Green, B W; Hinners, T; Hoffman, C R; Kemper, K W; Momotyuk, O; Peplowski, P; Pipidis, A; Reynolds, R; Roeder, B T

2006-11-10

The reaction 13C(alpha,n) is considered to be the main source of neutrons for the s process in asymptotic giant branch stars. At low energies, the cross section is dominated by the 1/2+ 6.356 MeV subthreshold resonance in (17)O whose contribution at stellar temperatures is uncertain by a factor of 10. In this work, we performed the most precise determination of the low-energy astrophysical S factor using the indirect asymptotic normalization (ANC) technique. The alpha-particle ANC for the subthreshold state has been measured using the sub-Coulomb alpha-transfer reaction ((6)Li,d). Using the determined ANC, we calculated S(0), which turns out to be an order of magnitude smaller than in the nuclear astrophysics compilation of reaction rates.

Estimation of the {alpha} particles and neutron distribution generated during a fusion reaction; Evaluation de la distribution des particules {alpha} et des neutrons issus de la reaction de fusion

Energy Technology Data Exchange (ETDEWEB)

Dellacherie, S.

1997-12-01

The respective distributions (or density probabilities) of {alpha} particles and neutrons have been modeled using a Monte-Carlo method for the thermonuclear fusion reaction D + T {yields} {alpha} + n + 17.6 MeV. (N.T.).

Mechanisms of the p(He 6,He 5)d, p(He 6,{alpha})t and p(He 6,t){alpha} reactions

Energy Technology Data Exchange (ETDEWEB)

Heiberg-Andersen, Henning

2002-07-01

This work was devoted to nucleon induced transfer reactions having the potential to probe the sub-cluster structures of the benchmark halo nucleus He 6, without the question marks the necessarily omitted exchange effects tend to put behind the CRC results when both collision partners are composite systems. Still, the exchange complications entered the analysis in an ironic way: The high Q-value of the p(He 6,{alpha})t and p(He 6, t){alpha} reactions caused sensitivity to the t - {alpha} optical potential at small radii, where the one-nucleon exchange effects are strongest. Since the attempt to throw them out of the extracted tau - {alpha} potential failed, it was necessary to extend the model space to avoid a too difficult modelling of the local equivalent t - {alpha} potential. By this step, all the complications originating from antisymmetrization within a larger model space entered the analysis. However, the persistent failures of the two-channel calculations of this and previous works can hardly be due to incorrect treatment of exchange effects only, so the loss of simplicity is probably illusory. Even at small angles, where the surface processes dominate, none of the two-channel calculations with various choices of t - {alpha} optical potentials managed to reproduce the p(He 6, {alpha})t (p(He 6,t){alpha}) data. This motivated inclusion of sequential transfers through the d + He 5 channel, where the sequential triton transfer process, included just for consistency in the coupling scheme of the four-channel calculation, turned out to be more influent than expected. The satisfactory reproduction of both the p(He 6, He 5)d and the p(He 6,{alpha})t (p(He 6,t){alpha}) data by the four-channel approach and the required re-normalization the real part of the p - He 6 optical potential are strong indications of substantial contributions from sequential transfer of the halo neutrons at this energy. The conclusions that can be drawn from this work are limited by the

Hydrozirconation of lithium alkynylselenolate anions. Generation and reactions of alpha-zirconated vinyl selenide intermediates

Science.gov (United States)

Dabdoub; Begnini; Guerrero; Baroni

2000-01-14

Lithium alkynylselenolate anions react completely with 1.0 equiv of Cp(2)Zr(H)Cl in THF at room temperature to give exclusively the alpha-zirconated vinylselenolate intermediates 23-27, which by treatment with an alkyl halide afforded the alpha-zirconated vinyl alkylselenide intermediates 29-33. Reaction of 29-33 with butyltellurenyl bromide results in the formation of ketene telluro(seleno) acetals 35-39 with total control of the regio- and stereochemistry. The synthetic utility of the ketene telluro(seleno) acetals obtained here was demonstrated by reaction of 36 with butyllithium. This promotes the exclusive and stereospecific removal of the tellurium moiety and enables formation of the corresponding selenium-containing allylic alcohol of type 44, alpha-(alkylseleno)-alpha,beta-unsaturated aldehyde 45, ester 46, or carboxylic acid 47, after reaction with different types of electrophiles.

Crosschecking of alpha particle monitor reactions up to 50 MeV

Energy Technology Data Exchange (ETDEWEB)

Takács, S., E-mail: stakacs@atomki.hu [Institute for Nuclear Research, Hungarian Academy of Sciences, 4026 Debrecen (Hungary); Ditrói, F.; Szűcs, Z. [Institute for Nuclear Research, Hungarian Academy of Sciences, 4026 Debrecen (Hungary); Haba, H.; Komori, Y. [Nishina Center for Accelerator-Based Science, RIKEN, Wako 351-0198 (Japan); Aikawa, M. [Faculty of Science, Hokkaido University, Sapporo 060-0810 (Japan); Nishina Center for Accelerator-Based Science, RIKEN, Wako 351-0198 (Japan); Saito, M. [Graduate School of Science, Hokkaido University, Sapporo 060-0810 (Japan); Nishina Center for Accelerator-Based Science, RIKEN, Wako 351-0198 (Japan)

2017-04-15

Selected reactions with well-defined excitation functions can be used to monitor the parameters of charged particle beams. The frequently used reactions for monitoring alpha particle beams are the {sup 27}Al(α,x){sup 22,24}Na, {sup nat}Ti(α,x){sup 51}Cr, {sup nat}Cu(α,x){sup 66,67}Ga and {sup nat}Cu(α,x){sup 65}Zn reactions. The excitation functions for these reactions were studied using the activation method and stacked target irradiation technique to crosscheck and to compare the above six reactions. Thin metallic foils with natural isotopic composition and well defined thickness were stacked together in sandwich targets and were irradiated at the AVF cyclotron of RIKEN with an alpha particle beam of 51.2 MeV. The activity of the target foils were assessed by using high-resolution gamma spectrometers of high purity Ge detectors. The data sets of the six processes were crosschecked with each other to provide consistent, cross-linked numerical cross section data.

Alpha cluster states in light nuclei populated through the (6Li,d) reaction

Energy Technology Data Exchange (ETDEWEB)

Borello-Lewin, Thereza; Rodrigues, M.R.D.; Horodynski-Matsushigue, L.B.; Duarte, J.L.M.; Rodrigues, C.L.; Souza, M.A. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica; Cunsolo, A.; Cappuzzello, F. [Universita di Catania (Italy). Istituto Nazionale di Fisica Nucleare. Lab. Nazionali del Sud; Ukita, Gilberto Mitsuo [Universidade de Santo Amaro (UNISA), Sao Paulo, SP (Brazil). Fac. de Psicologia

2011-07-01

Full text: The alpha cluster correlation is an important concept in the nuclear physics of light nuclei. The main purpose of the research program in progress is the investigation of the alpha clustering phenomenon in (x{alpha}) and(x{alpha}+{nu}) nuclei through the ({sup 6}Li,d) alpha transfer reaction. In fact, there is scarce experimental information on the subject, in particular associated with resonant states predicted near (x{alpha}) and (x{alpha}+{nu}) thresholds. Measurements of the {sup 12},{sup 13}C({sup 6}Li,d) {sup 16},{sup 17}O reactions, at an incident energy of 25.5 MeV, have been performed employing the Sao Paulo Pelletron-Enge Split-Pole facility and the nuclear emulsion detection technique. The work is under way and an experimental energy resolution of 30 keV was obtained. Near the (4{alpha}) breakup threshold in {sup 16}O, three narrow alpha resonances, not previously measured, were detected, revealing important {alpha} + {sup 12}C(G.S.) components. One of these resonances corresponds to the known 0{sup +} state at 15.1 MeV[5] of excitation that has probably, according to Funaki et al., the gas like configuration of the 4{alpha} condensate state, with a very dilute density and a large component of {alpha} + {sup 12}C(Hoyle) configuration. As was already mentioned, our experimental information points to the necessity of including the {alpha} + {sup 12}C(G.S.) component in the wave function. (author)

Neutrino-induced charged-current reaction rates for r-process nuclei

CERN Document Server

Langanke, K

2001-01-01

Neutrino-induced reactions play an important role during and after the r-process if it occurs in an environment with extreme neutrino fluxes, as in the neutrino-driven wind model or neutron star mergers. The neutrino reactions can excite the daughter nucleus above the neutron threshold, which is quite low for r-process nuclei. Thus the daughter nucleus will decay by emission of one or several neutrons. We have calculated the relevant total (nu sub e , e sup -) cross sections as well as the partial neutron spallation cross sections for r-process nuclei with neutron numbers N=41-135 and proton numbers Z=21-82. The supernova neutrino spectrum is described by a Fermi-Dirac distribution with various temperature parameters between T=2.8 MeV and T=10 MeV and with the degeneracy parameters alpha=0 and alpha=3. Our calculations of the nuclear response are based on the random phase approximation and consider allowed as well as forbidden transitions.

Experimental investigation of the reactions {sup 25}Mg({alpha},n){sup 28}Si, {sup 26}Mg({alpha},n){sup 29}Si, {sup 18}O({alpha},n){sup 21}Ne and their impact on stellar nucleosynthesis

Energy Technology Data Exchange (ETDEWEB)

Falahat, Sascha

2010-06-10

In the present dissertation, the nuclear reactions {sup 25}Mg({alpha},n){sup 28}Si, {sup 26}Mg({alpha},n){sup 29}Si, {sup 18}O({alpha},n){sup 21}Ne are investigated in the astrophysically interesting energy region from E{sub {alpha}}=1000 keV to E{sub {alpha}}=2450 keV. The experiments were performed at the Nuclear Structure Laboratory of the University of Notre Dame (USA) with the Van-de-Graaff accelerator KN. Solid state targets with evaporated magnesium or anodized oxygen were bombarded with {alpha}-particles and the released neutrons detected. For the detection of the released neutrons, computational simulations were used to construct a neutron detector based on {sup 3}He counters. Because of the strong occurrence of background reactions, different methods of data analysis were employed. Finally, the impact of the reactions {sup 25}Mg({alpha},n){sup 28}Si, {sup 26}Mg({alpha},n){sup 29}Si, {sup 18}O({alpha},n){sup 21}Ne on stellar nucleosynthesis is investigated by means of network calculations. (orig.)

Phenomenological analisis of the p-even- and p,odd-angular asimmetry of alpha particles in the 10B(n, α)7Li reaction with thermal polarized neutrons

International Nuclear Information System (INIS)

Rzhevskij, E.S.

1983-01-01

The formalism for multilevel phenomfor munological analysis of angular asymmetry of alpha-particles escape from compound-nuclei in reactions induced by thermal polarized neutrons is suggested. The formalism is based on R-matrix theory of nuclear reactions. The connection of problems of angular correlations description with those of light nuclei structure is shown. The problems related to the selection of compound-resonance parameters, determination of alpha-cluster states, estimation of the role of these or those compound-resonances in neutron and alpha-particle channels are discussed. An explanation is given to the observed in the experiment p-even left/right angular asymmetry of alpha-particles. The values of p-odd angular correlations, the measurements of which are continued, are estimated

Resonance analysis of the {sup 12}C,{sup 13}C({alpha},n) reactions and evaluation of neutron yield data of the reaction

Energy Technology Data Exchange (ETDEWEB)

Murata, Toru [AITEL Corp., Tokyo (Japan)

1998-03-01

The {sup 12}C({alpha},n){sup 15}O reaction and the {sup 13}C({alpha},n){sup 16}O reaction were analyzed with a resonance formula in the incident {alpha}-particle energy range of 1.0 to 16.0 MeV. With the obtained resonance parameters, branching ratios of the emitted neutrons to the several levels of the residual nucleus and their angular distributions were calculated to obtain the energy spectrum of emitted neutrons. Thick target neutron yield of carbon were also calculated and compared with the experimental data. (author)

Calculated /alpha/-induced thick target neutron yields and spectra, with comparison to measured data

International Nuclear Information System (INIS)

Wilson, W.B.; Bozoian, M.; Perry, R.T.

1988-01-01

One component of the neutron source associated with the decay of actinide nuclides in many environments is due to the interaction of decay /alpha/ particles in (/alpha/,n) reactions on low Z nuclides. Measurements of (/alpha/,n) thick target neutron yields and associated neutron spectra have been made for only a few combinations of /alpha/ energy and target nuclide or mixtures of actinide and target nuclides. Calculations of thick target neutron yields and spectra with the SOURCES code require /alpha/-energy-dependent cross sections for (/alpha/,n) reactions, as well as branching fractions leading to the energetically possible levels of the product nuclides. A library of these data has been accumulated for target nuclides of Z /le/ 15 using that available from measurements and from recent GNASH code calculations. SOURCES, assuming neutrons to be emitted isotopically in the center-of-mass system, uses libraries of /alpha/ stopping cross sections, (/alpha/,n) reaction cross reactions, product nuclide level branching fractions, and actinide decay /alpha/ spectra to calculate thick target (/alpha/,n) yields and neutron spectra for homogeneous combinations of nuclides. The code also calculates the thick target yield and angle intergrated neutron spectrum produced by /alpha/-particle beams on targets of homogeneous mixtures of nuclides. Illustrative calculated results are given and comparisons are made with measured thick target yields and spectra. 50 refs., 1 fig., 2 tabs

Alpha-Driven MHD and MHD-Induced Alpha Loss in TFTR DT Experiments

Science.gov (United States)

Chang, Zuoyang

1996-11-01

Theoretical calculation and numerical simulation indicate that there can be interesting interactions between alpha particles and MHD activity which can adversely affect the performance of a tokamak reactor (e.g., ITER). These interactions include alpha-driven MHD, like the toroidicity-induced-Alfven-eigenmode (TAE) and MHD induced alpha particle losses or redistribution. Both phenomena have been observed in recent TFTR DT experiments. Weak alpha-driven TAE activity was observed in a NBI-heated DT experiment characterized by high q0 ( >= 2) and low core magnetic shear. The TAE mode appears at ~30-100 ms after the neutral beam turning off approximately as predicted by theory. The mode has an amplitude measured by magnetic coils at the edge tildeB_p ~1 mG, frequency ~150-190 kHz and toroidal mode number ~2-3. It lasts only ~ 30-70 ms and has been seen only in DT discharges with fusion power level about 1.5-2.0 MW. Numerical calculation using NOVA-K code shows that this type of plasma has a big TAE gap. The calculated TAE frequency and mode number are close to the observation. (2) KBM-induced alpha particle loss^1. In some high-β, high fusion power DT experiments, enhanced alpha particle losses were observed to be correlated to the high frequency MHD modes with f ~100-200 kHz (the TAE frequency would be two-times higher) and n ~5-10. These modes are localized around the peak plasma pressure gradient and have ballooning characteristics. Alpha loss increases by 30-100% during the modes. Particle orbit simulations show the added loss results from wave-particle resonance. Linear instability analysis indicates that the plasma is unstable to the kinetic MHD ballooning modes (KBM) driven primarily by strong local pressure gradients. ----------------- ^1Z. Chang, et al, Phys. Rev. Lett. 76 (1996) 1071. In collaberation with R. Nazikian, G.-Y. Fu, S. Batha, R. Budny, L. Chen, D. Darrow, E. Fredrickson, R. Majeski, D. Mansfield, K. McGuire, G. Rewoldt, G. Taylor, R. White, K

Quantitative surface analysis using deuteron-induced nuclear reactions

International Nuclear Information System (INIS)

Afarideh, Hossein

1991-01-01

The nuclear reaction analysis (NRA) technique consists of looking at the energies of the reaction products which uniquely define the particular elements present in the sample and it analysis the yield/energy distribution to reveal depth profiles. A summary of the basic features of the nuclear reaction analysis technique is given, in particular emphasis is placed on quantitative light element determination using (d,p) and (d,alpha) reactions. The experimental apparatus is also described. Finally a set of (d,p) spectra for the elements Z=3 to Z=17 using 2 MeV incident deutrons is included together with example of more applications of the (d,alpha) spectra. (author)

Reaction /sup 56/Fe (. gamma. ,. cap alpha. /sub 0/) and /sup 56/Fe (. gamma. , p/sub 0/)

Energy Technology Data Exchange (ETDEWEB)

Tamae, T; Sugawara, M [Tohoku Univ., Sendai (Japan). Lab. of Nuclear Science; Tsubota, H

1975-06-01

Precise analysis was made on the cross section of the /sup 56/Fe (..gamma.., ..cap alpha../sub 0/) reaction and the angular distribution at Esub(e) = 17 MeV, including the systematic error. The (..gamma.., ..cap alpha../sub 0/) reaction cross section was compared with a calculation using the compound nucleus model, utilizing the photon absorption cross section derived from the experimental values of /sup 56/Fe (..gamma.., n) and /sup 56/Fe (..gamma.., p) cross sections. From the (..gamma.., ..cap alpha../sub 0/) reaction cross section data of various nuclei, an empirical formula was obtained for determining the position of a peak in the (..gamma.., ..cap alpha../sub 0/) reaction cross section. The /sup 56/Fe (..gamma.., p/sub 0/) reaction cross section measured at an excitation energy in the range of 14.6--25.0 MeV was compared with the calculated one with the compound nucleus model, but the form and size differ totally.

Measurements of neutron-induced capture and fission reactions on $^{235}$ U: cross sections and ${\\alpha}$ ratios, photon strength functions and prompt ${\\gamma}$-ray from fission

CERN Multimedia

We propose to measure the neutron-induced capture cross section of the fissile isotope $^{235}$U using a fission tagging set-up. This new set-up has been tested successfully in 2010 and combines the n_TOF 4${\\pi}$ Total Absorption Calorimeter (TAC) with MicroMegas (MGAS) fission detectors. It has been proven that such a combination of detectors allows distinguishing with very good reliability the electromagnetic cascades from the capture reactions from dominant ${\\gamma}$-ray background coming from the fission reactions. The accurate discrimination of the fission background is the main challenge in the neutron capture cross section measurements of fissile isotopes. The main results from the measurement will be the associated capture cross section and ${\\alpha}$ ratio in the resolved (0.3-2250 eV) and unresolved (2.25-30 keV) resonance regions. According to the international benchmarks and as it is mentioned in the NEA High Priority Request List (HPRL), the 235U(n,${\\gamma}$) cross section is of utmost impo...

Cytokine vaccination: neutralising IL-1alpha autoantibodies induced by immunisation with homologous IL-1alpha

DEFF Research Database (Denmark)

Svenson, M; Hansen, M B; Thomsen, Allan Randrup

2000-01-01

with IL-1alpha coupled to purified protein derivative of tuberculin (PPD). Both unprimed and primed animals developed IgG aAb to IL-1alpha. These aAb persisted at high levels more than 100 days after vaccination and did not cross-react with murine IL-1beta. The induced anti-IL-1alpha aAb inhibited binding...... in mice by vaccination with recombinant murine IL-1alpha conjugated to PPD. Studies of the effects of IL-1alpha aAb in such animals may help clarify the importance of naturally occurring IL-1alpha aAb in humans and permit the evaluation of future therapies with cytokine aAb in patients...

Trojan Horse Method and RIBs: The {sup 18}F(p,{alpha}){sup 15}O reaction at astrophysical energies

Energy Technology Data Exchange (ETDEWEB)

Cherubini, S.; Gulino, M.; Rapisarda, G. G.; Spitaleri, C.; La Cognata, M.; Lamia, L.; Kubono, S.; Yamaguchi, H.; Hayakawa, S.; Wakabayashi, Y.; Iwasa, N.; Kato, S.; Komatsubara, H.; Teranishi, T.; Coc, A.; De Sereville, N.; Hammache, F. [Dipartimento di Fisica ed Astronomia, Universita di Catania and INFN-LNS, Catania (Italy); INFN-LNS, Catania (Italy) and UniKORE, Enna (Italy)

2012-11-12

The abundance of {sup 18}F in Nova explosions is an important issue for the understanding of this astrophysical phenomenon. For this reason it is necessary to study the nuclear reactions that produce or destroy this isotope in novae. Among these latter processes, the {sup 18}F(p,{alpha}){sup 15}O is one of the main {sup 18}F destruction channels. We report here on the preliminary results of the first experiment that applies the Trojan Horse Method to a Radioactive Ion Beam induced reaction. The experiment was performed using the CRIB apparatus of the Center for Nuclear Study of The Tokyo University.

Integral excitation functions for proton and alpha induced reactions on target elements 22 <= Z <= 28

International Nuclear Information System (INIS)

Brinkmann, G.

1979-01-01

In the framework of a systematic study which is also important for certain cosmological questions a series of integral excitation functions of p- and α-induced nuclear reactions on target elements 22 [de

Differences between Drug-Induced and Contrast Media-Induced Adverse Reactions Based on Spontaneously Reported Adverse Drug Reactions.

Science.gov (United States)

Ryu, JiHyeon; Lee, HeeYoung; Suh, JinUk; Yang, MyungSuk; Kang, WonKu; Kim, EunYoung

2015-01-01

We analyzed differences between spontaneously reported drug-induced (not including contrast media) and contrast media-induced adverse reactions. Adverse drug reactions reported by an in-hospital pharmacovigilance center (St. Mary's teaching hospital, Daejeon, Korea) from 2010-2012 were classified as drug-induced or contrast media-induced. Clinical patterns, frequency, causality, severity, Schumock and Thornton's preventability, and type A/B reactions were recorded. The trends among causality tools measuring drug and contrast-induced adverse reactions were analyzed. Of 1,335 reports, 636 drug-induced and contrast media-induced adverse reactions were identified. The prevalence of spontaneously reported adverse drug reaction-related admissions revealed a suspected adverse drug reaction-reporting rate of 20.9/100,000 (inpatient, 0.021%) and 3.9/100,000 (outpatients, 0.004%). The most common adverse drug reaction-associated drug classes included nervous system agents and anti-infectives. Dermatological and gastrointestinal adverse drug reactions were most frequently and similarly reported between drug and contrast media-induced adverse reactions. Compared to contrast media-induced adverse reactions, drug-induced adverse reactions were milder, more likely to be preventable (9.8% vs. 1.1%, p contrast media-induced adverse reactions (56.6%, p = 0.066). Causality patterns differed between the two adverse reaction classes. The World Health Organization-Uppsala Monitoring Centre causality evaluation and Naranjo algorithm results significantly differed from those of the Korean algorithm version II (p contrast media-induced adverse reactions. The World Health Organization-Uppsala Monitoring Centre and Naranjo algorithm causality evaluation afforded similar results.

Protection against cyanide-induced convulsions with alpha-ketoglutarate.

Science.gov (United States)

Yamamoto, H

1990-04-30

Protection against convulsions induced by cyanide was observed after treatment with alpha-ketoglutarate, either alone or in combination with sodium thiosulfate, a classical antagonist for cyanide intoxication. However, sodium thiosulfate alone did not protect against cyanide (30 mg/kg)-induced convulsions. gamma-Aminobutyric acid (GABA) levels in brain were decreased by 31% in KCN-treated mice exhibiting convulsions. The combined administration of alpha-ketoglutarate and sodium thiosulfate completely abolished the decrease of GABA levels induced by cyanide. Furthermore, sodium thiosulfate alone also completely abolished the decrease of GABA levels. These results suggest that the depletion of brain GABA levels may not directly contribute to the development of convulsions induced by cyanide. On the other hand, cyanide increased calcium levels by 32% in brain crude mitochondrial fractions in mice with convulsions. The increased calcium levels were completely abolished by the combined administration of alpha-ketoglutarate and sodium thiosulfate, but not affected by sodium thiosulfate alone. These findings support the hypothesis proposed by Johnson et al. (Toxicol. Appl. Pharmacol., 84 (1986) 464) and Robinson et al. (Toxicology, 35 (1985) 59) that calcium may play an important role in mediating cyanide neurotoxicity.

First Accurate Normalization of the $\\beta$-delayed $\\alpha$ Decay of $^{16}$N and Implications for the $^{12}$C$(\\alpha,\\gamma)^{16}$O Astrophysical Reaction Rate arXiv

CERN Document Server

Kirsebom, O.S.; Lica, R.; Munch, M.; Riisager, K.; Fynbo, H.O.U.; Borge, M.J.G.; Madurga, M.; Marroquin, I.; Andreyev, A.N.; Berry, T.A.; Christensen, E.R.; Fernández, P. Díaz; Doherty, D.T.; Van Duppen, P.; Fraile, L.M.; Gallardo, M.C.; Greenlees, P.T.; Harkness-Brennan, L.J.; Hubbard, N.; Huyse, M.; Jensen, J.H.; Johansson, H.; Jonson, B.; Judson, D.S.; Konki, J.; Lazarus, I.; Lund, M.V.; Marginean, N.; Marginean, R.; Perea, A.; Mihai, C.; Negret, A.; Page, R.D.; Pucknell, V.; Rahkila, P.; Sorlin, O.; Sotty, C.; Swartz, J.A.; Sørensen, H.B.; Törnqvist, H.; Vedia, V.; Warr, N.; De Witte, H.

The $^{12}$C$(\\alpha,\\gamma)^{16}$O reaction plays a central role in astrophysics, but its cross section at energies relevant for astrophysical applications is only poorly constrained by laboratory data. The reduced $\\alpha$ width, $\\gamma_{11}$, of the bound $1^-$ level in $^{16}$O is particularly important to determine the cross section. The magnitude of $\\gamma_{11}$ is determined via sub-Coulomb $\\alpha$-transfer reactions or the $\\beta$-delayed $\\alpha$ decay of $^{16}$N, but the latter approach is presently hampered by the lack of sufficiently precise data on the $\\beta$-decay branching ratios. Here we report improved branching ratios for the bound $1^-$ level and for $\\beta$-delayed $\\alpha$ emission. In the case of the $\\beta$-delayed $\\alpha$ branch, we find a $5\\sigma$ deviation from the literature value. With our new branching ratios, the constraints imposed on $\\gamma_{11}$ by the $\\beta\\alpha$-decay and $\\alpha$-transfer data are of similar precision and, for the first time, in good agreement. Th...

Infrared laser-induced chemical reactions

International Nuclear Information System (INIS)

Katayama, Mikio

1978-01-01

The experimental means which clearly distinguishes between infrared ray-induced reactions and thermal reactions has been furnished for the first time when an intense monochromatic light source has been obtained by the development of infrared laser. Consequently, infrared laser-induced chemical reactions have started to develop as one field of chemical reaction researches. Researches of laser-induced chemical reactions have become new means for the researches of chemical reactions since they were highlighted as a new promising technique for isotope separation. Specifically, since the success has been reported in 235 U separation using laser in 1974, comparison of this method with conventional separation techniques from the economic point of view has been conducted, and it was estimated by some people that the laser isotope separation is cheaper. This report briefly describes on the excitation of oscillation and reaction rate, and introduces the chemical reactions induced by CW laser and TEA CO 2 laser. Dependence of reaction yield on laser power, measurement of the absorbed quantity of infrared ray and excitation mechanism are explained. Next, isomerizing reactions are reported, and finally, isotope separation is explained. It was found that infrared laser-induced chemical reactions have the selectivity for isotopes. Since it is evident that there are many examples different from thermal and photo-chemical reactions, future collection of the data is expected. (Wakatsuki, Y.)

Hypoxia-inducible factor-1 alpha has a key role in hypoxic preconditioning.

Science.gov (United States)

Taie, Satoshi; Ono, Junichiro; Iwanaga, Yasuyuki; Tomita, Shuhei; Asaga, Takehiko; Chujo, Kosuke; Ueki, Masaaki

2009-08-01

Sublethal hypoxia induces tolerance to subsequent hypoxic insults in a process known as hypoxic preconditioning (HP). Hypoxia-inducible factor-1 alpha (HIF-1 alpha) is a key transcription protein involved in the mechanism of HP. In this study, we investigated the effects of HP on tissue oxygenation and expression of HIF-1 alpha gene targets in the brain using neural cell-specific HIF-1 alpha-deficient mice. The animals were exposed to 8% oxygen for 3 hours. Twenty-four hours later, the oxygen partial pressure (pO(2)) of brain tissue and gene expression were measured during hypoxia. HP improved the pO(2) of brain tissue during subsequent hypoxia with upregulated inducible nitric oxide synthase in wild-type mice, whereas HP had no detectable effect in the mutant mice. Our results indicate that the protective effects of HP may be partially mediated by improving tissue oxygenation via HIF-1 alpha and inducible nitric oxide synthase.

Influence of Magnolol on the bystander effect induced by alpha-particle irradiation

Energy Technology Data Exchange (ETDEWEB)

Wong, T.P.W.; Law, Y.L. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong); Tse, A.K.W.; Fong, W.F. [Research and Development Division, School of Chinese Medicine, Hong Kong Baptist University, Baptist University Road, Kowloon Tong (Hong Kong); Yu, K.N. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong)], E-mail: peter.yu@cityu.edu.hk

2010-04-15

In this work, the influence of Magnolol on the bystander effect in alpha-particle irradiated Chinese hamster ovary (CHO) cells was examined. The bystander effect was studied through medium transfer experiments. Cytokinesis-block micronucleus (CBMN) assay was performed to quantify the chromosome damage induced by alpha-particle irradiation. Our results showed that the alpha-particle induced micronuclei (MN) frequencies were suppressed with the presence of Magnolol.

Nuclear transfer reaction measurements at the ESR-for the investigation of the astrophysical O-15(alpha,gamma)Ne-19 reaction

NARCIS (Netherlands)

Doherty, D. T.; Woods, P. J.; Litvinov, Yu A.; Najafi, M. Ali; Bagchi, S.; Bishop, S.; Bo, M.; Brandau, C.; Davinson, T.; Dillmann, I.; Estrade, A.; Egelhof, P.; Evdokimov, A.; Gumberidze, A.; Heil, M.; Lederer, C.; Litvinov, S. A.; Lotay, G.; Kalantar-Nayestanaki, N.; Kiselev, O.; Kozhuharov, C.; Kroell, T.; Mahjour-Shafei, M.; Mutterer, M.; Nolden, F.; Petridis, N.; Popp, U.; Reifarth, R.; Rigollet, C.; Roy, S.; Steck, M.; Stoehlker, Th; Streicher, B.; Trotsenko, S.; von Schmid, M.; Yan, X. L.; Zamora, J. C.

2015-01-01

Astrophysical x-ray bursts are thought to be a result of thermonuclear explosions on the atmosphere of an accreting neutron star. Between these bursts, energy is thought to be generated by the hot CNO cycles. The O-15(alpha,gamma)Ne-19 reaction is one reaction that allows breakout from these CNO

Nuclear transfer reaction measurements at the ESR-for the investigation of the astrophysical O-15(alpha,gamma)Ne-19 reaction

NARCIS (Netherlands)

Doherty, D. T.; Woods, P. J.; Litvinov, Yu A.; Najafi, M. Ali; Bagchi, S.; Bishop, S.; Bo, M.; Brandau, C.; Davinson, T.; Dillmann, I.; Estrade, A.; Egelhof, P.; Evdokimov, A.; Gumberidze, A.; Heil, M.; Lederer, C.; Litvinov, S. A.; Lotay, G.; Kalantar-Nayestanaki, N.; Kiselev, O.; Kozhuharov, C.; Kroell, T.; Mahjour-Shafei, M.; Mutterer, M.; Nolden, F.; Petridis, N.; Popp, U.; Reifarth, R.; Rigollet, C.; Roy, S.; Steck, M.; Stoehlker, Th; Streicher, B.; Trotsenko, S.; von Schmid, M.; Yan, X. L.; Zamora, J. C.

Astrophysical x-ray bursts are thought to be a result of thermonuclear explosions on the atmosphere of an accreting neutron star. Between these bursts, energy is thought to be generated by the hot CNO cycles. The O-15(alpha,gamma)Ne-19 reaction is one reaction that allows breakout from these CNO

Alpha-induced instabilities in tandem thermal barriers

Energy Technology Data Exchange (ETDEWEB)

Kammash, T.; Galbraith, D.L.

1987-01-01

A major premise in the operation of Tandem Mirror reactors is that the fusion reactions take place in the central cell only. The alpha particles generated by the Deuterium-Tritium (DT) fusions, along with other ions, will however pass from the central cell to the thermal barriers and return to the central cell as a result of reflection by the potential hills that exist by the plugs' side of these barriers. This streaming motion gives rise to electrostatic and electomagnetic instabilities which could detract from the barrier's function as a thermal insulator. The number density and streaming velocity of these passing particles are dictated by the electrostatic potential variation and the magnetic field structure in these regions. It is shown that, in the absence of alphas, barriers with deep potential depression are less susceptible to electrostatic instabilities while particularly vulnerable to unstable electromagnetic modes. In the presence of alphas, especially the fast alphas whose mean energy is significantly larger than the barrier potentials they see, (which is twice as high as that seen by the ions) both types of modes become unstable.

Inelastic Branch of the Stellar Reaction $^{14}$O$(\\alpha,p)^{17}$F

CERN Multimedia

Hass, M; Van duppen, P L E

2002-01-01

We propose to use the upgraded REX-ISOLDE beam energy to study the astrophysically important $^{14}$O($\\alpha$, p)$^{17}$F reaction in time reverse kinematics. In particular, we will use the highly efficient miniball + CD detection system to measure the previously undetermined inelastic proton branch of the 1$^-$ state at 6.15 MeV in $^{18}$Ne. This state dominates the reaction rate under X-ray burster conditions.

Determination of alpha-naphthol by an oscillating chemical reaction using the analyte pulse perturbation technique

International Nuclear Information System (INIS)

Yang Wu; Sun Kanjun; Lv Weilian; Bo Lili; He Xiaoyan; Suo Nan; Gao Jinzhang

2005-01-01

An analytical method for the determination of alpha-naphthol (α-NP) is proposed by the sequential perturbation caused by different amounts of alpha-naphthol on the oscillating chemical system involving the Cu(II)-catalyzed oscillating reaction between hydrogen peroxide and sodium thiocyanate in an alkaline medium with the aid of continuous-flow stirred tank reactor (CSTR). The method relies on the linear relationship between the changes in the oscillation amplitude of the chemical system and the concentration of alpha-naphthol. The use of the analyte pulse perturbation technique permits sequential determinations in the same oscillating system owing to the expeditiousness with which the steady state is regained after each perturbation. The calibration curve obeys a linear equation very well when the concentration of alpha-naphthol is over the range 0.034-530 umol/L (r = 0.9991). Influences of temperature, injection points, flow rate and reaction variables on the oscillating system are investigated in detail and the possible mechanism of action of alpha-naphthol to the chemical oscillating system is also discussed. The method has been successfully used for the determination of α-naphthol in carbaryl hydrolysates

In-beam study of the rotational states in actinides after alpha-induced nuclear reactions

International Nuclear Information System (INIS)

Hardt, K.

1983-01-01

In the experiments described in this thesis the ground state rotational bands of a whole series of actinide isotopes has been studied by means of α-induced nuclear reactions. The rotational bands studied in the even isotopes could be identified up to a spin of about 16 (h/2π). With this data it was now possible to establish a broad systematic of the rotational energies up to relatively high angular momenta. Also in the odd isotopes 233 U and 239 Pu it was possible to follow the ground state rotational bands up to higher spins and to compare them with predictions of the rotational model. By means of the (α,α'2n) reaction the nuclei 230 Th and especially 228 Th could by populated. (orig./HSI) [de

Alpha-driven magnetohydrodynamics (MHD) and MHD-induced alpha loss in the Tokamak Fusion Test Reactor

International Nuclear Information System (INIS)

Chang, Z.; Nazikian, R.; Fu, G.Y.

1997-02-01

Alpha-driven toroidal Alfven eigenmodes (TAEs) are observed as predicted by theory in the post neutral beam phase in high central q (safety factor) deuterium-tritium (D-T) plasmas in the Tokamak Fusion Test Reactor (TFTR). The mode location, poloidal structure and the importance of q profile for TAE instability are discussed. So far no alpha particle loss due to these modes was detected due to the small mode amplitude. However, alpha loss induced by kinetic ballooning modes (KBMs) was observed in high confinement D-T discharges. Particle orbit simulation demonstrates that the wave-particle resonant interaction can explain the observed correlation between the increase in alpha loss and appearance of multiple high-n (n ≥ 6, n is the toroidal mode number) modes

Fasting induces basolateral uptake transporters of the SLC family in the liver via HNF4alpha and PGC1alpha.

Science.gov (United States)

Dietrich, Christoph G; Martin, Ina V; Porn, Anne C; Voigt, Sebastian; Gartung, Carsten; Trautwein, Christian; Geier, Andreas

2007-09-01

Fasting induces numerous adaptive changes in metabolism by several central signaling pathways, the most important represented by the HNF4alpha/PGC-1alpha-pathway. Because HNF4alpha has been identified as central regulator of basolateral bile acid transporters and a previous study reports increased basolateral bile acid uptake into the liver during fasting, we hypothesized that HNF4alpha is involved in fasting-induced bile acid uptake via upregulation of basolateral bile acid transporters. In rats, mRNA of Ntcp, Oatp1, and Oatp2 were significantly increased after 48 h of fasting. Protein expression as determined by Western blot showed significant increases for all three transporters 72 h after the onset of fasting. Whereas binding activity of HNF1alpha in electrophoretic mobility shift assays remained unchanged, HNF4alpha binding activity to the Ntcp promoter was increased significantly. In line with this result, we found significantly increased mRNA expression of HNF4alpha and PGC-1alpha. Functional studies in HepG2 cells revealed an increased endogenous NTCP mRNA expression upon cotransfection with either HNF4alpha, PGC-1alpha, or a combination of both. We conclude that upregulation of the basolateral bile acid transporters Ntcp, Oatp1, and Oatp2 in fasted rats is mediated via the HNF4alpha/PGC-1alpha pathway.

Omentin inhibits TNF-{alpha}-induced expression of adhesion molecules in endothelial cells via ERK/NF-{kappa}B pathway

Energy Technology Data Exchange (ETDEWEB)

Zhong, Xia, E-mail: zhongxia1977@126.com [Department of Emergency, Provincial Hospital Affiliated to Shandong University, Jinan 250021 (China); Li, Xiaonan; Liu, Fuli; Tan, Hui [Department of Emergency, Provincial Hospital Affiliated to Shandong University, Jinan 250021 (China); Shang, Deya, E-mail: wenhuashenghuo1@163.com [Department of Emergency, Provincial Hospital Affiliated to Shandong University, Jinan 250021 (China)

2012-08-24

Highlights: Black-Right-Pointing-Pointer Omentin inhibited TNF-{alpha}-induced adhesion of THP-1 cells to HUVECs. Black-Right-Pointing-Pointer Omentin reduces expression of ICAM-1 and VCAM-1 induced by TNF-{alpha} in HUVECs. Black-Right-Pointing-Pointer Omentin inhibits TNF-{alpha}-induced ERK and NF-{kappa}B activation in HUVECs. Black-Right-Pointing-Pointer Omentin supreeses TNF-{alpha}-induced expression of ICAM-1 and VCAM-1 via ERK/NF-{kappa}B pathway. -- Abstract: In the present study, we investigated whether omentin affected the expression of intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in tumor necrosis factor-{alpha} (TNF-{alpha}) induced human umbilical vein endothelial cells (HUVECs). Our data showed that omentin decreased TNF-{alpha}-induced expression of ICAM-1 and VCAM-1 in HUVECs. In addition, omentin inhibited TNF-{alpha}-induced adhesion of THP-1 cells to HUVECs. Further, we found that omentin inhibited TNF-{alpha}-activated signal pathway of nuclear factor-{kappa}B (NF-{kappa}B) by preventing NF-{kappa}B inhibitory protein (I{kappa}B{alpha}) degradation and NF-{kappa}B/DNA binding activity. Omentin pretreatment significantly inhibited TNF-{alpha}-induced ERK activity and ERK phosphorylation in HUVECs. Pretreatment with PD98059 suppressed TNF-{alpha}-induced NF-{kappa}B activity. Omentin, NF-kB inhibitor (BAY11-7082) and ERK inhibitor (PD98059) reduced the up-regulation of ICAM-1 and VCAM-1 induced by TNF-{alpha}. These results suggest that omentin may inhibit TNF-{alpha}-induced expression of adhesion molecules in endothelial cells via blocking ERK/NF-{kappa}B pathway.

Scattering of alpha particles from /sup 12/C and the /sup 12/C(. cap alpha. ,. gamma. )/sup 16/O stellar reaction rate

Energy Technology Data Exchange (ETDEWEB)

Plaga, R.; Becker, H.W.; Redder, A.; Rolfs, C.; Trautvetter, H.P.; Langanke, K.

1987-04-06

The elastic scattering of alpha particles from /sup 12/C has been investigated for 35 angles in the range theta/sub lab/ = 22/sup 0/ to 163/sup 0/ and for 51 energies at E/sub ..cap alpha../ = 1.0 to 6.6 MeV. The extracted phase shifts for l=0 to 6 partial waves have been parametrized in terms of the multilevel R-matrix formalism. Information on the deduced parameters of states in /sup 16/O is reported. The data reveal reduced ..cap alpha..-particle widths for the 6.92 and 7.12 MeV subthreshold states consistent with recent work. The implications for the stellar reaction rate of /sup 12/C(..cap alpha..,..gamma..)/sup 16/O are discussed.

Regular endurance training reduces the exercise induced HIF-1alpha and HIF-2alpha mRNA expression in human skeletal muscle in normoxic conditions

DEFF Research Database (Denmark)

Lundby, Carsten; Gassmann, Max; Pilegaard, Henriette

2005-01-01

and 2 (HIFs) are clearly related heterodimeric transcription factors that consist of an oxygen-depended alpha-subunit and a constitutive beta-subunit. With hypoxic exposure, HIF-1alpha and HIF-2alpha protein are stabilized. Upon heterodimerization, HIFs induce the transcription of a variety of genes......Regular exercise induces a variety of adaptive responses that enhance the oxidative and metabolic capacity of human skeletal muscle. Although the physiological adjustments of regular exercise have been known for decades, the underlying mechanisms are still unclear. The hypoxia inducible factors 1...... including erythropoietin (EPO), transferrin and its receptor, as well as vascular endothelial growth factor (VEGF) and its receptor. Considering that several of these genes are also induced with exercise, we tested the hypothesis that the mRNA level of HIF-1alpha and HIF-2alpha subunits increases...

A brief review of ultra-rare alpha decay detection technique

International Nuclear Information System (INIS)

Tsyganov, Yu.S.

2006-01-01

Three approaches to the measurement of rare alpha decaying products produced in heavy-ion induced nuclear reactions are described. One is based on a chemical extraction and following deposition of the nuclides under investigation onto the surface of the detector, whereas the second one is associated with long-lived products implanted into silicon detectors by using the electromagnetic separation technique. The third approach relates with an application of real-time mode detection of correlated energy-time-position recoil-alpha sequences from 48 Ca-induced nuclear reactions with actinide targets, like 242,244 Pu, 245,248 Cm, 243 Am, and 249 Cf. Namely with this technique it has became possible to provide a radical suppression of backgrounds in the full fusion (3-5n) reactions aimed at the synthesis of superheavy elements with Z = 113-118

Neutrino-induced neutral-current reaction cross sections for r-process nuclei

CERN Document Server

Langanke, K

2002-01-01

Neutrino-induced reactions play an important role during and after the r-process, if the latter occurs in an environment with extreme neutrino fluxes such as the neutrino-driven wind model or neutron star mergers. Recently we have evaluated the charged-current neutrino-nucleus cross sections relevant for r-process simulations. We extend our approach here to the neutral-current cross sections. Our tabulation considers neutron-rich nuclei with neutron numbers N=41-135 and charge numbers Z=21-82 and lists total as well as partial neutron spallation cross sections. The calculations have been performed within the random phase approximation considering multipole transitions with J<=3 and both parities. The supernova neutrino spectrum is described by a Fermi-Dirac distribution with various temperature parameters between T=2.8 MeV and T=10 MeV and with the degeneracy parameters alpha=0 and alpha=3.

alpha-Adrenoceptor and opioid receptor modulation of clonidine-induced antinociception.

Science.gov (United States)

Sierralta, F; Naquira, D; Pinardi, G; Miranda, H F

1996-10-01

1. The antinociceptive action of clonidine (Clon) and the interactions with alpha 1, alpha 2 adrenoceptor and opioid receptor antagonists was evaluated in mice by use of chemical algesiometric test (acetic acid writhing test). 2. Clon produced a dose-dependent antinociceptive action and the ED50 for intracerebroventricular (i.c.v.) was lower than for intraperitoneal (i.p.) administration (1 ng kg-1 vs 300 ng kg-1). The parallelism of the dose-response curves indicates activation of a common receptor subtype. 3. Systemic administration of prazosin and terazosin displayed antinociceptive activity. Pretreatment with prazosin produced a dual action: i.c.v. Clon effect did not change, and i.p. Clon effect was enhanced. Yohimbine i.c.v. or i.p. did not induce antinonciception, but antagonized Clon-induced activity. These results suggest that alpha 1- and alpha 2-adrenoceptors, either located at the pre- and/or post-synaptic level, are involved in the control of spinal antinociception. 4. Naloxone (NX) and naltrexone (NTX) induced antinociceptive effects at low doses (microgram kg-1 range) and a lower antinociceptive effect at higher doses (mg kg-1 range). Low doses of NX or NTX antagonized Clon antinociception, possibly in relation to a preferential mu opioid receptor antagonism. In contrast, high doses of NX or NTX increased the antinociceptive activity of Clon, which could be due to an enhanced inhibition of the release of substance P. 5. The results obtained in the present work suggest the involvement of alpha 1-, alpha 2-adrenoceptor and opioid receptors in the modulation of the antinociceptive activity of clonidine, which seems to be exerted either at spinal and/or supraspinal level.

Reconstruction of spin-tensor of 4. 43 MeV state density matrix of the /sup 12/C nucleus in the /sup 12/C(. cap alpha. ,. cap alpha. sub(1). gamma. sub(4,43))/sup 12/C reaction at Esub(. cap alpha. )=25 MeV

Energy Technology Data Exchange (ETDEWEB)

Gurevich, G.S.; Lebedev, V.M.; Orlova, N.V.; Spasskij, A.V.; Teplov, I.B.; Shakhvorostova, G.V.; Belkina, M.R. (Moskovskij Gosudarstvennyj Univ. (USSR). Nauchno-Issledovatel' skij Inst. Yadernoj Fiziki)

1984-01-01

The results of measuring double differential cross sections of the reaction of inelastic scattering 24.8 MeV ..cap alpha..-particles sup(12)C(..cap alpha.., ..cap alpha..sub(1)..gamma..sub(4.43))sup(12)C in different planes of ..gamma..-quantum escape relatively to the plane of the reaction phisub(..gamma..)=30, 60 and 90 deg are presented. Non-monochromaticity of the beam made up 1%. Functions of angular correlation of the reaction are measured for four angles THETAsub(..cap alpha..)=21, 39, 59 and 135 deg corresponding to maxima of differential cross section in angular distribution of inelastically scattered ..cap alpha..-particles and for THETAsub(..cap alpha..)=89 deg corresponding to the minimum of angular distribution. The results of measurements permit to reconstruct all the components of irreducible spin-tensors of the matrix of state density 4.43 MeV (2/sup +/) formed in this reaction. The values of populations of substates by the projection of the spin of this state are obtained. The analysis of the obtained results testify to the fact that mechanism of inelastic scattering is not reduced to impulse approximation and mechanisms associated with delay in interaction do not make noticeable contribution for the given angles of ..cap alpha..-particle escape.

alpha-Amanitin induced apoptosis in primary cultured dog hepatocytes.

Directory of Open Access Journals (Sweden)

Adam Szelag

2010-06-01

Full Text Available Amatoxin poisoning is caused by mushroom species belonging to the genera Amanita, Galerina and Lepiota with the majority of lethal mushroom exposures attributable to Amanita phalloides. High mortality rate in intoxications with these mushrooms is principally a result of the acute liver failure following significant hepatocyte damage due to hepatocellular uptake of amatoxins. A wide variety of amatoxins have been isolated; however, alpha-amanitin (alpha-AMA appears to be the primary toxin. Studies in vitro and in vivo suggest that alpha-AMA does not only cause hepatocyte necrosis, but also may lead to apoptotic cell death. The objective of this study was to evaluate the complex hepatocyte apoptosis in alpha-AMA cytotoxicity. All experiments were performed on primary cultured canine hepatocytes. The cells were incubated for 12 h with alpha-AMA at a final concentration of 1, 5, 10 and 20 microM. Viability test (MTT assay, apoptosis evaluation (TUNEL reaction, detection of DNA laddering and electron microscopy were performed at 6 and 12 h of exposure to alpha-AMA. There was a clear correlation between hepatocyte viability, concentration of alpha-AMA and time of exposure to this toxin. The decline in cultured dog hepatocyte viability during the exposure to alpha-AMA is most likely preceded by enhanced cellular apoptosis. Our results demonstrate that apoptosis might contribute to pathogenesis of the severe liver injury in the course of amanitin intoxication, particularly during the early phase of poisoning.

Investigation of (n, p) and (n, alpha) reactions with thermal and resonance energy neutrons

CERN Document Server

Gledenov, Yu M

2002-01-01

Influence of results of (n, alpha) and (n, p) reactions cross section and asymmetry measurements on certain branches of fundamental and applied science is considered. For instance, some of the cross sections are critical for comprehension of many scenarios of nuclear synthesis in the Universe. They are also used for studying some aspects of nuclear structure and fundamental symmetries, such as mixing of isospin and non-retaining of spatial parity. And, finally, cross sections of the reactions are of applied interest, for reactor materials technologies specifically. Types of sources and methods of (n, p) and (n, alpha) reactions measurements in energy range of thermal and resonance neutrons are described in the review. Special attention is paid to measurements in radioactive relatively short-lived samples and very small stable samples. Several examples of the measurements are provided, which are of scientific interest, as they permit demonstrating the method used. Possible future measurements are discussed in ...

Levels in {sup 227}Ac populated in the {sup 230}Th(p,{alpha}) reaction

Energy Technology Data Exchange (ETDEWEB)

Burke, D.G. E-mail: dgb@physics.mcmaster.ca; Garrett, P.E.; Qu, Tao

2003-09-08

The {sup 230,232}Th(p,{alpha}){sup 227,229}Ac reactions were studied using 20 MeV protons and a magnetic spectrograph to analyze the reaction products. Relative populations of levels in {sup 229}Ac correlated well with previously published (t,{alpha}) results for the same final levels, showing that the similarity of the two reactions observed empirically in the deformed rare earth region extends to actinides. The most strongly populated level in {sup 227}Ac is at 639 keV, and is assigned as the 1/2{sup +}[4 0 0] bandhead. The 435 keV level, previously adopted as the 1/2{sup +}[6 6 0] bandhead, also has a significant intensity that is attributed to {delta}N=2 mixing between these two K=1/2 proton orbitals. The {delta}N=2 matrix element estimated from these data is {approx}80 keV, similar to values observed for the same two Nilsson states as neutron orbitals in the dysprosium isotopes.

Expression of hypoxia-induced factor-1 alpha in early-stage and in metastatic oral squamous cell carcinoma.

Science.gov (United States)

Ribeiro, Maisa; Teixeira, Sarah R; Azevedo, Monarko N; Fraga, Ailton C; Gontijo, Antônio Pm; Vêncio, Eneida F

2017-04-01

To investigate hypoxia-induced factor-1 alpha expression in distinct oral squamous cell carcinoma subtypes and topographies and correlate with clinicopathological data. Hypoxia-induced factor-1 alpha expression was assessed by immunohistochemistry in 93 cases of OSCC. Clinical and histopathological data were reviewed from medical records. Hypoxia-induced factor-1 alpha status was distinct according to tumor location, subtype and topography affect. In superficial oral squamous cell carcinomas, most tumor cells overexpressed hypoxia-induced factor-1 alpha, whereas hypoxia-induced factor-1 alpha was restricted to the intratumoral region in conventional squamous cell carcinomas. All basaloid squamous cell carcinomas exhibited downregulation of hypoxia-induced factor-1 alpha. Interestingly, metastatic lymph nodes (91.7%, p = 0.001) and the intratumoral regions of corresponding primary tumors (58.3%, p = 0.142) showed hypoxia-induced factor-1 alpha-positive tumor cells. Overall survival was poor in patients with metastatic lymph nodes. Hypoxia-induced factor-1 alpha has distinct expression patterns in different oral squamous cell carcinoma subtypes and topographies, suggesting that low oxygen tension promotes the growth pattern of superficial and conventional squamous cell carcinoma, but not basaloid squamous cell carcinoma. Indeed, a hypoxic environment may facilitate regional metastasis, making it a useful diagnostic and prognostic marker in primary tumors.

Alpha cluster states in light nuclei populated through the (6Li,d) reaction

International Nuclear Information System (INIS)

Borello-Lewin, Thereza; Rodrigues, M.R.D.; Horodynski-Matsushigue, L.B.; Duarte, J.L.M.; Rodrigues, C.L.; Souza, M.A.; Cunsolo, A.; Cappuzzello, F.; Ukita, Gilberto Mitsuo

2011-01-01

Full text: The alpha cluster correlation is an important concept in the nuclear physics of light nuclei. The main purpose of the research program in progress is the investigation of the alpha clustering phenomenon in (xα) and(xα+ν) nuclei through the ( 6 Li,d) alpha transfer reaction. In fact, there is scarce experimental information on the subject, in particular associated with resonant states predicted near (xα) and (xα+ν) thresholds. Measurements of the 12 , 13 C( 6 Li,d) 16 , 17 O reactions, at an incident energy of 25.5 MeV, have been performed employing the Sao Paulo Pelletron-Enge Split-Pole facility and the nuclear emulsion detection technique. The work is under way and an experimental energy resolution of 30 keV was obtained. Near the (4α) breakup threshold in 16 O, three narrow alpha resonances, not previously measured, were detected, revealing important α + 12 C(G.S.) components. One of these resonances corresponds to the known 0 + state at 15.1 MeV[5] of excitation that has probably, according to Funaki et al., the gas like configuration of the 4α condensate state, with a very dilute density and a large component of α + 12 C(Hoyle) configuration. As was already mentioned, our experimental information points to the necessity of including the α + 12 C(G.S.) component in the wave function. (author)

A large area position-sensitive ionization chamber for heavy-ion-induced reaction studies

CERN Document Server

Pant, L M; Dinesh, B V; Thomas, R G; Saxena, A; Sawant, Y S; Choudhury, R K

2002-01-01

A large area position-sensitive ionization chamber with a wide dynamic range has been developed to measure the mass, charge and energy of the heavy ions and the fission fragments produced in heavy-ion-induced reactions. The split anode geometry of the detector makes it suitable for both particle identification and energy measurements for heavy ions and fission fragments. The detector has been tested with alpha particles from sup 2 sup 4 sup 1 Am- sup 2 sup 3 sup 9 Pu source, fission fragments from sup 2 sup 5 sup 2 Cf and the heavy-ion beams from the 14UD Mumbai Pelletron accelerator facility. Using this detector, measurements on mass and total kinetic energy distributions in heavy-ion-induced fusion-fission reactions have been carried out for a wide range of excitation energies. Results on deep inelastic collisions and mass-energy correlations on different systems using this detector setup are discussed.

Spontaneous local alpha oscillations predict motion-induced blindness.

Science.gov (United States)

Händel, Barbara F; Jensen, Ole

2014-11-01

Bistable visual illusions are well suited for exploring the neuronal states of the brain underlying changes in perception. In this study, we investigated oscillatory activity associated with 'motion-induced blindness' (MIB), which denotes the perceptual disappearance of salient target stimuli when a moving pattern is superimposed on them (Bonneh et al., ). We applied an MIB paradigm in which illusory target disappearances would occur independently in the left and right hemifields. Both illusory and real target disappearance were followed by an alpha lateralization with weaker contralateral than ipsilateral alpha activity (~10 Hz). However, only the illusion showed early alpha lateralization in the opposite direction, which preceded the alpha effect present for both conditions and coincided with the estimated onset of the illusion. The duration of the illusory disappearance was further predicted by the magnitude of this early lateralization when considered over subjects. In the gamma band (60-80 Hz), we found an increase in activity contralateral relative to ipsilateral only after a real disappearance. Whereas early alpha activity was predictive of onset and length of the illusory percept, gamma activity showed no modulation in relation to the illusion. Our study demonstrates that the spontaneous changes in visual alpha activity have perceptual consequences. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Excitation function of alpha-particle-induced reactions on {sup nat}Ni from threshold to 44 MeV

Energy Technology Data Exchange (ETDEWEB)

Uddin, M.S. [Atomic Energy Research Establishment, Tandem Accelerator Facilities, Institute of Nuclear Science and Technology, Savar, Dhaka (Bangladesh); Kim, K.S.; Nadeem, M.; Kim, G.N. [Kyungpook National University, Department of Physics, Buk-gu, Daegu (Korea, Republic of); Sudar, S. [Debrecen University, Institute of Experimental Physics, Debrecen (Hungary)

2017-05-15

Excitation functions of the {sup nat}Ni(α,x){sup 62,63,65}Zn, {sup nat}Ni(α,x){sup 56,57}Ni and {sup nat}Ni(α,x){sup 56,57,58m+g}Co reactions were measured from the respective thresholds to 44MeV using the stacked-foil activation technique. The tests for the beam characterization are described. The radioactivity was measured using HPGe γ-ray detectors. Theoretical calculations on α-particles-induced reactions on {sup nat}Ni were performed using the nuclear model code TALYS-1.8. A few results are new, the others strengthen the database. Our experimental data were compared with results of nuclear model calculations and described the reaction mechanism. (orig.)

Alpha-Methyldopa-Induced Autoimmune Hemolytic Anemia in the Third Trimester of Pregnancy

Directory of Open Access Journals (Sweden)

Charalampos Grigoriadis

2013-01-01

Full Text Available Alpha-methyldopa has been demonstrated to be safe for use during pregnancy and is now used to treat gestational hypertension. In pregnancy, alpha-methyldopa-induced autoimmune hemolytic anemia does not have typical features and the severity of symptoms ranges from mild fatigue to dyspnea, respiratory failure, and death if left untreated. A case of alpha-methyldopa-induced autoimmune hemolytic anemia in a 36-year-old gravida 2, para 1 woman at 37+6 weeks of gestation is reported herein along with the differential diagnostic procedure and the potential risks to the mother and the fetus.

Alpha-induced reaction cross section measurements on 151Eu for the astrophysical γ-process

International Nuclear Information System (INIS)

Gyuerky, Gy.; Elekes, Z.; Farkas, J.; Fueloep, Zs.; Halasz, Z.; Kiss, G.G.; Somorjai, E.; Szuecs, T.; Gueraya, R.T.; Oezkana, N.

2010-01-01

Compete text of publication follows. The astrophysical γ-process is the main production mechanism of the p-isotopes, the heavy, proton-rich nuclei not produced by neutron capture reactions in the astrophysical sand r-processes. The γ-process is a poorly known process of nucleosynthesis, the models are not able to reproduce well the p-isotope abundances observed in nature. Experimental data on nuclear reactions involved in γ-process reaction networks are clearly needed to provide input for a more reliable γ-process network calculation. As a continuation of our systematic study of reactions relevant for the γ-process, the cross sections of the 151 Eu(α, γ) 155 Tb and 151 Eu(α,n) 154 Tb reactions have been measured. These reactions have been chosen because α-induced cross section data in the region of heavy p-isotopes are almost completely missing although the calculations show a strong influence of these cross section on the resulting abundances. Since the reaction products of both reactions are radioactive, the cross sections have been measured using the activation technique. The targets have been prepared by evaporating Eu 2 O 3 enriched to 99.2% in 151 Eu onto thin Al foils. The target thicknesses have been measured by weighing and Rutherford Backscattering Spectroscopy. The targets have been irradiated by typically 1-2 μA intensity α-beams from the cyclotron of ATOMKI. The investigated energy range between 12 and 17 MeV was covered with 0.5 MeV steps. This energy range is somewhat higher than the astrophysically relevant one, but the cross section at astrophysical energies is so low that the measurements are not possible there. The γ- activity of the reaction products has been measured by a shielded HPGe detector. The absolute efficiency of the detector was measured with several calibration sources. Since 154 Tb has two long lived isomeric states, partial cross sections of the 151 Eu(α,n) 154 Tb reaction leading to the ground and isomeric states

AN UPDATED {sup 6}Li(p, {alpha}){sup 3}He REACTION RATE AT ASTROPHYSICAL ENERGIES WITH THE TROJAN HORSE METHOD

Energy Technology Data Exchange (ETDEWEB)

Lamia, L.; Spitaleri, C.; Sergi, M. L. [Dipartimento di Fisica e Astronomia, Universita di Catania, I-95123 Catania (Italy); Pizzone, R. G.; Tumino, A.; La Cognata, M. [INFN-Laboratori Nazionali del Sud, I-95125 Catania (Italy); Tognelli, E.; Degl' Innocenti, S.; Prada Moroni, P. G. [Dipartimento di Fisica, Universita di Pisa, I-56127 Pisa (Italy); Pappalardo, L. [Dipartimento di Fisica e Scienze della Terra, Universita di Ferrara, I-44100 Ferrara (Italy)

2013-05-01

The lithium problem influencing primordial and stellar nucleosynthesis is one of the most interesting unsolved issues in astrophysics. {sup 6}Li is the most fragile of lithium's stable isotopes and is largely destroyed in most stars during the pre-main-sequence (PMS) phase. For these stars, the convective envelope easily reaches, at least at its bottom, the relatively low {sup 6}Li ignition temperature. Thus, gaining an understanding of {sup 6}Li depletion also gives hints about the extent of convective regions. For this reason, charged-particle-induced reactions in lithium have been the subject of several studies. Low-energy extrapolations of these studies provide information about both the zero-energy astrophysical S(E) factor and the electron screening potential, U{sub e} . Thanks to recent direct measurements, new estimates of the {sup 6}Li(p, {alpha}){sup 3}He bare-nucleus S(E) factor and the corresponding U{sub e} value have been obtained by applying the Trojan Horse method to the {sup 2}H({sup 6}Li, {alpha} {sup 3}He)n reaction in quasi-free kinematics. The calculated reaction rate covers the temperature window 0.01 to 2T{sub 9} and its impact on the surface lithium depletion in PMS models with different masses and metallicities has been evaluated in detail by adopting an updated version of the FRANEC evolutionary code.

The reaction 32S(d,alpha)30P

International Nuclear Information System (INIS)

Lawrie, J.J.

1979-03-01

Cross sections for the reaction 32 S(d,alpha) 30 P were measured at an average deuteron energy of about 6 MeV over deuteron energy ranges of about 200 - 400 KeV with steps of 15 KeV and at laboratory angles of 90 degrees, 112 degrees, 125 degrees, 133 degrees, 137 degrees, 141 degrees, 148 degrees, 155 degrees and 175,5 degrees. The range of excitation pertaining to the study, extended to the 23rd excited state at 4,73 MeV in 30 P. The observed cross section fluctuations in the excitation functions are indicative of the statistical nature of the reaction. A coherence width of 43 plus minus 4 keV was obtained for the compound nucleus 34 Cl at 17,2 MeV excitation from fluctuation analyses for states up to the 7th excited level at 2,84 MeV in 30 P. By contrast the coherence width for the isospin forbidden transition to the T = 1 excited state at 2,94 MeV in 30 P was found to be 34 plus minus 6 keV. This difference can be accounted for in terms of isospin mixing in the compound nucleus. Spins of excited states in 30 P were determined by comparing experimental cross sections with Hauser-Feshbach predictions. The most probable spin values obtained from this study are: 1 + for the 10th (3,73 MeV),2 + for the 11th (3,83 MeV),3 + for the 12th (3,93 MeV),0 + for the 16th (4,235 MeV) and 1 + for the 23rd excited state at 4,73 MeV in 30 P. From the assumption that the spin of the 17th excited state (4,30 MeV) is 2 - , spin possibilities of 2 + , 3 - and 4 + could be deduced for the 18th excited state (4,34 MeV). An inhibition factor of 0,41 plus minus 0,06 for the isospin forbidden reaction 32 S(d,alpha) 30 P has been obtained and corresponds to a value of = 18 keV for the compound nucleus 34 Cl at 17,2 MeV excitation

Contribution to the study of the reaction p + {sup 11}B = 3 {alpha} by the coincidence method; Contribution a l'etude de la reaction p + {sup 11}B = 3 {alpha} par la methode des coincidences

Energy Technology Data Exchange (ETDEWEB)

Laugier, J Ph [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

1969-07-01

We have studied the production mode of the 3 {alpha} system in the reaction p + {sup 11}B = {sup 12}C{sup *} = {alpha} + {sup 8}Be{sup *}; {sup 8}Be{sup *} = {alpha} + {alpha}. We have got some information for three different effects: the influence of the {sup 8}Be residual nucleus states = sequential decay; the influence of the {sup 12}C compound nucleus states = spin effect; an interference effect. We give a theoretical expression of the different spectra which take into account the observed phenomena. We have taken, as a parameter, the phase shift, between the waves associated with the detected particles, which produce the interference effect. The main characteristics of the experimental devices are : self supporting boron targets; cooled semiconductor detectors; multi-parametric system: for each nuclear event three parameters are recorded: the energies of the detected particles and the time of the detection; Recording system: the information are recorded on a magnetic tape and at the same time treated with an on line CAE 510 computer. The CAE 510 computer is used in delayed time to analyse the experimental data. (author) [French] Nous avons etudie le mecanisme de production du systeme 3 {alpha} dans la reaction: p + {sup 11}B = {sup 12}C{sup *} = {alpha} + {sup 8}Be{sup *}; {sup 8}Be{sup *} = {alpha} + {alpha}. Cette etude nous a permis de mettre en evidence trois effets de nature differente: l'effet des niveaux du noyau intermediaire {sup 8}Be reaction sequentielle; l'effet des niveaux du noyau compose {sup 12}C = effet de spin; -un effet d'interferences. Nous avons pu donner une expression theorique du spectre, rendant compte d'une facon satisfaisante des phenomenes observes. Pour cela nous avons considere le dephasage, entre les ondes associees aux particules detectees, qui produit les interferences, comme un parametre arbitraire. Du point de vue experimental les caracteristiques principales du materiel utilise sont les suivantes: utilisation de cibles de

Production of medically useful bromine isotopes via alpha-particle induced nuclear reactions

Science.gov (United States)

Breunig, Katharina; Scholten, Bernhard; Spahn, Ingo; Hermanne, Alex; Spellerberg, Stefan; Coenen, Heinz H.; Neumaier, Bernd

2017-09-01

The cross sections of α-particle induced reactions on arsenic leading to the formation of 76,77,78Br were measured from their respective thresholds up to 37 MeV. Thin sediments of elemental arsenic powder were irradiated together with Al degrader and Cu monitor foils using the established stacked-foil technique. For determination of the effective α-particle energies and of the effective beam current through the stacks the cross-section ratios of the monitor nuclides 67Ga/66Ga were used. This should help resolve discrepancies in existing literature data. Comparison of the data with the available excitation functions shows some slight energy shifts as well as some differences in curve shapes. The calculated thick target yields indicate, that 77Br can be produced in the energy range Eα = 25 → 17 MeV free of isotopic impurities in quantities sufficient for medical application.

Production of medically useful bromine isotopes via alpha-particle induced nuclear reactions

Directory of Open Access Journals (Sweden)

Breunig Katharina

2017-01-01

Full Text Available The cross sections of α-particle induced reactions on arsenic leading to the formation of 76,77,78Br were measured from their respective thresholds up to 37 MeV. Thin sediments of elemental arsenic powder were irradiated together with Al degrader and Cu monitor foils using the established stacked-foil technique. For determination of the effective α-particle energies and of the effective beam current through the stacks the cross-section ratios of the monitor nuclides 67Ga/66Ga were used. This should help resolve discrepancies in existing literature data. Comparison of the data with the available excitation functions shows some slight energy shifts as well as some differences in curve shapes. The calculated thick target yields indicate, that 77Br can be produced in the energy range Eα = 25 → 17 MeV free of isotopic impurities in quantities sufficient for medical application.

Contribution of 194.1 keV Resonance to 17O(p, alpha) 14N Reaction Rate using R Matrix Code

International Nuclear Information System (INIS)

Chafa, A.; Messili, F.Z.; Barhoumi, S.

2009-01-01

Knowledge of the 17 O(p, alpha ) 14 N reaction rates is required for evaluating elemental abundances in a number of hydrogen - burning stellar sites. This reaction is specifically very important for nucleosynthesis of the rare oxygen isotope 17 O. Classical novae are thought to be a major source of 17 O in the Galaxy and produce the short-live radioisotope 18 F whose + decay is followed by a gamma ray emission which could be observed with satellites such as the Integral observatory. As the 17 O(p, alpha) 14 N and 17 O(p, alpha ) 18 F reactions govern the destruction of 17 O and the formation of 1 '8F, their rates are decisive in determining the final abundances of these isotopes. Stellar temperatures of primary importance for nucleosynthesis are typically in the ranges T = 0.01-0.1 GK for red giant, AGB, and massive stars, and T 0.01-0.4 GK for classical nova explosions In recent work, we observed, for the first time, a resonance a 183.3 keV corresponding to level in 18 F at Ex 5789.8 ± 0.3 keV. A new astrophysical parameters of this resonance are found. In this work we study this reaction using numerical code based on R matrix method including the new values of level energy and parameters of 183.3 keV resonance in order to show his contribution to 17 O(p, alpha) 14 N reaction rates. We also use old parameters values of this resonance given in Keiser work for comparison. We show that this resonance predominate the reaction rates in all range of stellar temperature for classical nova explosions. This is in good agreement with our work with experimental method. We also study cross section and differential cross section 17 O(p, alpha ) 14 N reaction with R matrix method

Lactobacillus casei secreting alpha-MSH induces the therapeutic effect on DSS-induced acute colitis in Balb/c Mice.

Science.gov (United States)

Yoon, Sun-Woo; Lee, Chul-Ho; Kim, Jeong-Yoon; Kim, Jie-Youn; Sung, Moon-Hee; Poo, Haryoung

2008-12-01

The neuropeptide alpha-melanocyte-stimulating hormone (alpha- MSH) has anti-inflammatory property by downregulating the expressions of proinflammatory cytokines. Because alpha-MSH elicits the anti-inflammatory effect in various inflammatory disease models, we examined the therapeutic effect of oral administration of recombinant Lactobacillus casei, which secretes alpha-MSH (L. casei-alpha-MSH), on dextran sulfate sodium (DSS)-induced colitis in Balb/c mice. Thus, we constructed the alpha-MSH-secreting Lactobacillus casei by the basic plasmid, pLUAT-ss, which was composed of a PldhUTLS promoter and alpha-amylase signal sequence from Streptococcus bovis strain. Acute colitis was induced by oral administration of 5% DSS in drinking water for 7 days. To investigate the effect of L. casei-alpha-MSH on the colitis, L. casei or L. casei-alpha-MSH was orally administered for 7 days and their effects on body weight, mortality rate, cytokine production, and tissue myeloperoxidase (MPO) activity were observed. Administration of L. casei-alpha-MSH reduced the symptom of acute colitis as assessed by body weight loss (DSS alone: 14.45+/-0. 2 g; L. casei-alpha- MSH: 18.2+/-0.12 g), colitis score (DSS alone: 3.6+/-0.4; L. casei-alpha-MSH: 1.4+/-0.6), MPO activity (DSS alone: 42.7+/-4.5 U/g; L. casei-alpha-MSH: 10.25+/-0.5 U/g), survival rate, and histological damage compared with the DSS alone mice. L. casei-alpha-MSH-administered entire colon showed reduced in vitro production of proinflammatory cytokines and NF-kappaB activation. The alpha-MSH-secreting recombinant L. casei showed significant anti-inflammatory effects in the murine model of acute colitis and suggests a potential therapeutic role for this agent in clinical inflammatory bowel diseases.

The contributions of adrenal hormones, hemodynamic factors, and the endotoxin-related stress reaction to stable prostaglandin analog-induced peripheral lymphopenia and neutrophilia.

Science.gov (United States)

Ulich, T R; Keys, M; Ni, R X; del Castillo, J; Dakay, E B

1988-01-01

-independent, hemodynamic-independent mechanisms. The possibility that M-PGF2 alpha might be inducing neutrophilia via an endotoxin-like stress reaction was investigated by examining changes in circulating white blood cells in intact and adrenalectomized C3H/HeN (endotoxin-sensitive) and C3H/HeJ (endotoxin-resistant) mice after prostaglandin administration. No quantitative differences in the prostaglandin-induced neutrophilia were noted in C3H/HeJ mice as compared to the C3H/HeN mice.(ABSTRACT TRUNCATED AT 400 WORDS)

Photon induced reactions

International Nuclear Information System (INIS)

Mecking, B.A.

1982-04-01

Various aspects of medium energy nuclear reactions induced by real photons are reviewed. Special emphasis is put on high accuracy experiments that will become possible with the next generation of electron accelerators. (orig.)

Research on the reactions {sup 9}Be ({sup 3}He, 3 {alpha}) and {sup 10}B (d, 3 {alpha}); Contribution a l'etude experimentale des reactions {sup 9}Be ({sup 3}He, 3 {alpha}) et {sup 10}B (d, 3 {alpha})

Energy Technology Data Exchange (ETDEWEB)

Thouvenin, P [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

1967-06-15

For studying these reactions, the detection of the final particles emitted in coincidence in the directions {theta}{sub 1} and {theta}{sub 2}, together with the bi-parametric analysis of the corresponding pulses are used. This method enables us to obtain the orthogonal Dalitz diagrams (E{sub 1}, E{sub 2}). An examination of the spectra obtained shows that the sequential mechanism appears to predominate. The contribution of the purely statistical process is less than 15 per cent of the total spectrum. In the case of {sup 10}B (d, 3 {alpha}), for E{sub d} = 1.5 MeV, 2,66 MeV and 3 MeV, the width of the peak of the first particles emitted, with respect to {sup 8}Be excitations close to 11 MeV, is found to be equal to 2.6 {+-} 0.6 MeV, much less than the width of the 2. excited state observed by {alpha} - {alpha} scattering. The coincidence spectra and the free spectra give an excitation energy of E{sub x} = 2.68 {+-} 0.07 MeV for the first excited state of {sup 8}Be. Some remarks are made concerning the anomalies observed for E{sub d} = 5 MeV and 9 MeV. The excited levels of {sup 8}Be at 13.91 MeV and 7.56 MeV which have been described in the past are not observed. (author) [French] La detection de deux des particules finales emises en cofncidence dans les directions {theta}{sub 1} et {theta}{sub 2}, et l'analyse biparametrique des impulsions correspondantes sont utilisees pour etudier ces reactions. Cette methode nous permet d'obtenir des diagrammes de Dalitz orthogonaux (E{sub 1}, E{sub 2}). L'examen des spectres obtenus montre que le mecanisme sequentiel semble predominant. La contribution du processus purement statistique est inferieure a 15 pour cent du spectre total. Dans le cas de {sup 10}B (d, 3 {alpha}), pour E{sub d} = 1,5 MeV, 2,66 MeV et 3 MeV, la largeur du pic des premieres particules emises relatives a des excitations de {sup 8}Be voisines de 11 MeV, est trouvee egale a 2,6 {+-} 0,6 MeV, tres inferieure a la largeur du 2. etat excite observee a l

Coincidence study of alpha particle fragmentation at E/sub alpha/ = 140 MeV

International Nuclear Information System (INIS)

Koontz, R.W.

1980-01-01

Results of an experimental study of the interaction of 140 MeV alpha particles with 90 Zr nuclei resulting in fragmentation of the alpha particle are reported. The experimental observations of the study are analyzed and are found to show that alpha particle breakup reactions leading to at least 4-body final states, composed of two charged alpha particle fragments, contribute significantly to the singles yield of charged fragments observed at a fixed forward angle. The conclusions are based on coincidence measurements where one charged fragment is detected at a small forward angle which remains fixed, while the second charged fragment is detected at a series of coplanar secondary angles. The largest coincidence charged particle yield for the multiparticle final state events results from 90 Zr(α,pp)X reactions, where both of the measured protons have energy distributions similar to the proton singles energy distributions. The second largest observed coincidence yield involving two charged fragments arises from 90 Zr(α,pd)X reactions, where the p and d fragments, as in the 90 Zr(α,pp)X reactions also have energy distribution similar to the singles energy distributions. Analysis of additional measurements, where alpha particle fragments at the fixed angle are detected in coincidence with evaporation and nonequilibrium particles at many coplanar angles, show that the alpha particle fragmentation reactions are also generally associated with large energy transfer to the target nucleus. A multiple scattering model of the fragmentation reaction is employed, in conjunction with the experimental observations, to estimate the cross sections for alpha particle fragmentation into multi-particle final states resulting in n, 2n, p, pp, d, dn, dp, t and 3 He fragments. The estimated total cross section for all fragmentation reactions is 755 mb or approximately 38% of the total reaction cross section for 140 MeV alpha particle interactions with 90 Zr

The E1 mechanism in photo-induced beta-elimination reactions for green-to-red conversion of fluorescent proteins.

Science.gov (United States)

Tsutsui, Hidekazu; Shimizu, Hideaki; Mizuno, Hideaki; Nukina, Nobuyuki; Furuta, Toshiaki; Miyawaki, Atsushi

2009-11-25

KikGR is a fluorescent protein engineered to display green-to-red photoconvertibility that is induced by irradiation with ultraviolet or violet light. Similar to Kaede and EosFP, two naturally occurring photoconvertible proteins, KikGR contains a His(62)-Tyr(63)-Gly(64) tripeptide sequence, which forms a green chromophore that can be photoconverted to a red one via formal beta-elimination and subsequent extension of a pi-conjugated system. Using a crystallizable variant of KikGR, we determined the structures of both the green and red state at 1.55 A resolution. The double bond between His(62)-C(alpha) and His(62)-C(beta) in the red chromophore is in a cis configuration, indicating that rotation along the His(62) C(alpha)-C(beta) bond occurs following cleavage of the His(62) N(alpha)-C(alpha) bond. This structural rearrangement provides evidence that the beta-elimination reaction governing the green-to-red photoconversion of KikGR follows an E1 (elimination, unimolecular) mechanism.

Angular distribution measurements of {sup 6}Li(p,{alpha}){sup 3}He reaction at 140 keV proton energy using nuclear track detectors

Energy Technology Data Exchange (ETDEWEB)

Al-Jarallah, M.I. E-mail: mibrahim@kfupm.edu.sa; Naqvi, A.A.; Abu-Jarad, F.A.; Fazal-ur-Rehman; Durrani, S.M.A.; Kidwai, S

2001-06-01

Angular distributions of a {sup 6}Li(p,{alpha}) {sup 3}He reaction were measured at six angles for 140 keV proton energy using nuclear track detectors (NTDs). The measurements were carried out over 60 deg. -160 deg. lab. angles in 20 deg. increments using a scattering chamber of 80 deg. beam line of the 350 kV accelerator. A semiconductor silicon surface barrier (SSB) detector was placed at +160 deg. and was used as a monitor. The results have shown that the CR-39 detector has excellent capabilities to distinguish 1.4-2.7 MeV {alpha}+ {sup 3}He particles from the {sup 6}Li(p,{alpha}) {sup 3}He reaction and 8-9.4 MeV {alpha}-particles from the {sup 7}Li(p,{alpha}) {sup 4}He reaction through their track diameters. However, it was not possible to distinguish between the 2.3 MeV {sup 3}He ions and the 1.7 MeV {sup 4}He ions from the {sup 6}Li(p,{alpha}) {sup 3}He reaction from their track diameter measurements, but it was possible to differentiate between the two, from the darker contrast of the {sup 3}He particles caused by its deeper tracks as compared to those of {sup 4}He.

Cross-section and reaction rates for some reactions involved in explosive nucleosynthesis

International Nuclear Information System (INIS)

Cheng, C.W.

1979-03-01

Total proton-induced and alpha-induced reaction cross sections have been determined for the 24 Mg(α,n), 25 Mg(p,n), 26 Mg(p,n), 27 Al(p,n), 28 Si(α,n), 42 Ca(p,γ), 42 Ca(α,n) and 44 Ca(p,n) reactions from energies near threshold (except the exothermic (p,γ) reaction) to about 3 to 4 MeV above threshold. The product nuclei are all positron emitters with half-lives ranging from about 3 sec to about 4 hours. From the measured cross sections reaction rates have been calculated in the temperature range 1 9 9 =1, at which the discrepancy is large. Included also are analytic forms for (p,n), (α,n), and (p,γ) reactions which can be used to describe the reaction rate within the temperature range 1 9 <=6 and which agree with the experimental rates at the discrete temperatures where the reaction rates have been calculated

Contribution to the study of (d,p) and (d,{alpha}> reactions on {sup 16}O and {sup 11}B from 200 keV to 1 MeV; Contribution a l'etude des reactions (d,p) et (d,{alpha}) sur {sup 16}O et {sup 11}B de 200 keV a 1 MeV

Energy Technology Data Exchange (ETDEWEB)

Longequeue, N [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1965-05-01

The reactions {sup 16}O(d,{alpha}{sub 0}), (d,p{sub 0}), (d,p{sub 1}) and {sup 11}B(d,{alpha}{sub 0}), (d,{alpha}{sub 2}), (d,p{sub 0}) have been studied from 200 keV to 1 MeV. The interpretation of (d,{alpha}) reactions by the compound nucleus theory has shown the presence of {sup 18}F levels (7,94 MeV, 1+; 8,09 MeV, 1+ ) and of {sup 13}C level (19 MeV, 3/2{+-} or 5/2-). The interpretation of {sup 16}O(d,p{sub 1}) and {sup 11}B(d,p{sub 0}) reactions at energies lower than 400 keV has been given by a theory of Coulomb stripping. (author) [French] L'etude experimentale des reactions {sup 16}O(d,{alpha}{sub 0}); (d,p{sub 0}), (d,p{sub 1}) et {sup 11}B(d,{alpha}{sub 0}), (d,{alpha}{sub 2}), (d,p{sub 0}) a ete faite de 200 keV a 1 Mev. L'interpretation des reactions (d,a) par la theorie du noyau compose a permis la mise en evidence de niveaux du {sup 18}F (7,94 MeV, 1+; 8,09MeV, 1+ ) et du {sup 13}C(19 MeV, 3/2{+-} ou 5/2-). L'interpretation des reactions {sup 16}O(d,p{sub 1}) et {sup 11}B(d,p{sub 0}), a basse energie (< 400 keV), par une theorie de stripping de Coulomb, a ete donnee.

Study of the {sup 18}F(p,{alpha}){sup 15}O reaction by transfer reaction for application to {gamma}-ray emission from Novae; Etude de la reaction {sup 18}F(p,{alpha}){sup 15}O par reaction de transfert pour application a l'emission {gamma} des Novae

Energy Technology Data Exchange (ETDEWEB)

Sereville, N. de

2003-12-15

The gamma emission from novae at/or below 511 keV is due to the annihilation of the positrons produced in the beta + decay of F{sup 18}. The interpretation of this emission through observations made by the Integral satellite for instance, requires a good knowledge of F{sup 18} nucleosynthesis. The reaction rate of the F{sup 18}(p,{alpha})O{sup 15} is the least known because of 2 resonances corresponding to the levels 6.419 and 6.449 MeV of Ne{sup 19} whose proton widths are completely unknown. We have determined these proton widths via the study of one-nucleon transfer reaction D(F{sup 18},p{alpha})N{sup 15} populating equivalent levels in F{sup 19}. We have used a 14 MeV F{sup 18} radioactive beam on a CD{sub 2} target for inverse kinematics studies and the multi-track silicon detector LEDA. A DWBA (Distorted Wave Bound Approximation) has enabled us to determine the proton width of both resonances and has showed that they have an impact in the calculation of the reaction rate. A thorough study of the remaining uncertainties of the reaction rate has been undertaken, particularly for those concerning interferences between these resonances and a higher resonance of Ne{sup 19}. The reaction rate that we have obtained is very similar to the previous rate used but now it rests on a more solid basis.

Coincidence measurement between. cap alpha. -particles and projectile-like fragments in reaction of 82. 7 MeV /sup 16/O on /sup 27/Al

Energy Technology Data Exchange (ETDEWEB)

Wen-Qing, Shen; Wen-long, Zhan; Yong-tai, Zhu; Shu-zhi, Yin; Zhong-yan, Guo; Wei-min, Qiao; Guo-ying, Fan; Gen-ming, Jin; Song-ling, Li; Zhen, Zhang; others, and

1987-01-01

In the coincidence measurement between ..cap alpha..-particles and projectile-like fragments in the reaction of 82.7 MeV /sup 16/O on /sup 27/Al, the contour plot of the C-..cap alpha.. coincidence in the velocity plane and the coincident angular correlation are obtained. Different mechanisms of ..cap alpha..-particle emission are analysed. A possible reaction mechanism of incomplete DIC is discussed.

Drug-Induced Endoplasmic Reticulum and Oxidative Stress Responses Independently Sensitize Toward TNF alpha-Mediated Hepatotoxicity

NARCIS (Netherlands)

Fredriksson, Lisa; Wink, Steven; Herpers, Bram; Benedetti, Giulia; Hadi, Mackenzie; de Bont, Hans; Groothuis, Geny; Luijten, Mirjam; Danen, Erik; de Graauw, Marjo; Meerman, John; van de Water, Bob

Drug-induced liver injury (DILI) is an important clinical problem. Here, we used a genomics approach to in detail investigate the hypothesis that critical drug-induced toxicity pathways act in synergy with the pro-inflammatory cytokine tumor necrosis factor alpha (TNF alpha) to cause cell death of

Recombinant human acetylcholine receptor alpha-subunit induces chronic experimental autoimmune myasthenia gravis.

Science.gov (United States)

Lennon, V A; Lambert, E H; Leiby, K R; Okarma, T B; Talib, S

1991-04-01

A synthetic gene encoding the 210 N-terminal residues of the alpha-subunit of the nicotinic acetylcholine receptor (AChR) of human skeletal muscle was cloned into an inducible expression plasmid to produce a fusion protein in high yield in Escherichia coli. Like native human AChR, the recombinant human alpha 1-210 protein induced AChR-binding, AChR-modulating, and AChR-blocking autoantibodies in rats when injected once intradermally as an emulsion in CFA, with Bordetella pertussis vaccine as supplementary adjuvant. The minimum dose of recombinant protein required to induce biochemical signs of experimental autoimmune myasthenia gravis (EAMG) with 100% incidence was 2.2 micrograms. With 6.6 to 22 micrograms, serum levels of autoantibodies were persistent, and clinically apparent EAMG lasted more than a month. Clinical, electrophysiological, and biochemical indices of EAMG induced by doses of 66 micrograms or more were more uniformly severe and persistent, with 33% fatality. Rats receiving a control extract of E. coli containing plasmid without the alpha 1-210 codon insert, with adjuvants, did not develop autoantibodies or signs of EAMG. This highly reproducible new model of EAMG induced by a recombinant human autoantigen should be valuable for testing Ag-specific immunotherapeutic strategies that might be applicable to treating acquired myasthenia gravis in humans.

Calculations on precompound reactions with alpha particles, A(α,α')X, at incident energies around 500 MeV

International Nuclear Information System (INIS)

Rittershausen, W.

1987-01-01

The model of Chiang et al. (1980) for nucleon induced precompound reactions, a generalization of the Glauber theory to lower energetical processes, was extended to heavier projectiles the elementary differential cross section of which may furthermore (at fixed incident energy) depend on the momentum transfer. The so modified model was applied to reactions of the type A(α,α')X at an incident energy of about 100 MeV/nucleon, excitation energies of the nucleus in the range 6 to 60 MeV, and for scattering angles from 3 to 6 0 . Thereby the Glauber coefficients were determined by means of the optical potentials known for the treated experiments. Local nucleon momentum distributions in the target nucleus were taken from calculations of Durand et al. (1982). The momentum distributions of the alpha particles after the first α-N collision were both for normalously and for homogeneously distributed nucleon momenta calculated analytically. The distributions after the second collision were determined by folding. For the control of these results and for the eventual calculation of the distributions after more than two collisions a Monte Carlo routine was written. The additional deviation of the alpha particles in real-valued potentials of the target nucleus were regarded. The results in which no free parameter occurs agree quite well in the shape with measured data. In one case it is also valid for the absolute quantities. (orig.) [de

Studies on excitation functions of alpha-induced reactions on {sup nat}Fe from threshold to 45 MeV

Energy Technology Data Exchange (ETDEWEB)

Kim, K.S.; Kim, G.N.; Zaman, M. [Kyungpook National University, Department of Physics, Daegu (Korea, Republic of); Uddin, M.S. [Atomic Energy Research Establishment, Tandem Accelerator Facilities, Institute of Nuclear Science and Technology, Dhaka (Bangladesh)

2018-01-15

Excitation functions of the {sup nat}Fe(α, x){sup 57}Ni, {sup nat}Fe(α, x){sup 55,56,57,58m,g}Co and {sup nat}Fe(α, x){sup 52,54}Mn reactions were measured using the stacked-foil activation technique. The induced radioactivities in both the target and monitor foils were measured using an off-line γ-ray spectrometric technique. The cross sections for the above reactions were also calculated theoretically using the TALYS-1.8 code. The measured results were compared with the other experimental data and theoretical values. The theoretically calculated values are described well by our experimental data. It is observed that the rate of proton emission is larger than the neutron one. The measured results for the formation of few radionuclides are new and the other measured data strengthen the database. The experimental and theoretical studies on the investigated reactions should lead to a useful insight into the mechanisms of those reactions. (orig.)

Retinal neuroprotection by hypoxic preconditioning is independent of hypoxia-inducible factor-1 alpha expression in photoreceptors.

Science.gov (United States)

Thiersch, Markus; Lange, Christina; Joly, Sandrine; Heynen, Severin; Le, Yun Zheng; Samardzija, Marijana; Grimm, Christian

2009-06-01

Hypoxic preconditioning stabilizes hypoxia-inducible factor (HIF) 1 alpha in the retina and protects photoreceptors against light-induced cell death. HIF-1 alpha is one of the major transcription factors responding to low oxygen tension and can differentially regulate a large number of target genes. To analyse whether photoreceptor-specific expression of HIF-1 alpha is essential to protect photoreceptors by hypoxic preconditioning, we knocked down expression of HIF-1 alpha specifically in photoreceptor cells, using the cyclization recombinase (Cre)-lox system. The Cre-mediated knockdown caused a 20-fold reduced expression of Hif-1 alpha in the photoreceptor cell layer. In the total retina, RNA expression was reduced by 65%, and hypoxic preconditioning led to only a small increase in HIF-1 alpha protein levels. Accordingly, HIF-1 target gene expression after hypoxia was significantly diminished. Retinas of Hif-1 alpha knockdown animals did not show any pathological alterations, and tolerated hypoxic exposure in a comparable way to wild-type retinas. Importantly, the strong neuroprotective effect of hypoxic preconditioning against light-induced photoreceptor degeneration persisted in knockdown mice, suggesting that hypoxia-mediated survival of light exposure does not depend on an autocrine action of HIF-1 alpha in photoreceptor cells. Hypoxia-mediated stabilization of HIF-2 alpha and phosphorylation of signal transducer and activator of transcription 3 (STAT 3) were not affected in the retinas of Hif-1 alpha knockdown mice. Thus, these factors are candidates for regulating the resistance of photoreceptors to light damage after hypoxic preconditioning, along with several potentially neuroprotective genes that were similarly induced in hypoxic knockdown and control mice.

Research on the reactions {sup 9}Be ({sup 3}He, 3 {alpha}) and {sup 10}B (d, 3 {alpha}); Contribution a l'etude experimentale des reactions {sup 9}Be ({sup 3}He, 3 {alpha}) et {sup 10}B (d, 3 {alpha})

Energy Technology Data Exchange (ETDEWEB)

Thouvenin, P. [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

1967-06-15

For studying these reactions, the detection of the final particles emitted in coincidence in the directions {theta}{sub 1} and {theta}{sub 2}, together with the bi-parametric analysis of the corresponding pulses are used. This method enables us to obtain the orthogonal Dalitz diagrams (E{sub 1}, E{sub 2}). An examination of the spectra obtained shows that the sequential mechanism appears to predominate. The contribution of the purely statistical process is less than 15 per cent of the total spectrum. In the case of {sup 10}B (d, 3 {alpha}), for E{sub d} = 1.5 MeV, 2,66 MeV and 3 MeV, the width of the peak of the first particles emitted, with respect to {sup 8}Be excitations close to 11 MeV, is found to be equal to 2.6 {+-} 0.6 MeV, much less than the width of the 2. excited state observed by {alpha} - {alpha} scattering. The coincidence spectra and the free spectra give an excitation energy of E{sub x} = 2.68 {+-} 0.07 MeV for the first excited state of {sup 8}Be. Some remarks are made concerning the anomalies observed for E{sub d} = 5 MeV and 9 MeV. The excited levels of {sup 8}Be at 13.91 MeV and 7.56 MeV which have been described in the past are not observed. (author) [French] La detection de deux des particules finales emises en cofncidence dans les directions {theta}{sub 1} et {theta}{sub 2}, et l'analyse biparametrique des impulsions correspondantes sont utilisees pour etudier ces reactions. Cette methode nous permet d'obtenir des diagrammes de Dalitz orthogonaux (E{sub 1}, E{sub 2}). L'examen des spectres obtenus montre que le mecanisme sequentiel semble predominant. La contribution du processus purement statistique est inferieure a 15 pour cent du spectre total. Dans le cas de {sup 10}B (d, 3 {alpha}), pour E{sub d} = 1,5 MeV, 2,66 MeV et 3 MeV, la largeur du pic des premieres particules emises relatives a des excitations de {sup 8}Be voisines de 11 MeV, est trouvee egale a 2,6 {+-} 0,6 MeV, tres inferieure a la largeur du 2. etat excite

PPAR{alpha} deficiency augments a ketogenic diet-induced circadian PAI-1 expression possibly through PPAR{gamma} activation in the liver

Energy Technology Data Exchange (ETDEWEB)

Oishi, Katsutaka, E-mail: k-ooishi@aist.go.jp [Biological Clock Research Group, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki (Japan); Uchida, Daisuke [Biological Clock Research Group, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki (Japan); Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki (Japan); Ohkura, Naoki [Department of Clinical Molecular Biology, Faculty of Pharmaceutical Sciences, Teikyo University, Sagamihara, Kanagawa (Japan); Horie, Shuichi [Department of Clinical Biochemistry, Kagawa Nutrition University, Sakado, Saitama (Japan)

2010-10-15

Research highlights: {yields} PPAR{alpha} deficiency augments a ketogenic diet-induced circadian PAI-1 expression. {yields} Hepatic expressions of PPAR{gamma} and PCG-1{alpha} are induced by a ketogenic diet. {yields} PPAR{gamma} antagonist attenuates a ketogenic diet-induced PAI-1 expression. {yields} Ketogenic diet advances the phase of circadian clock in a PPAR{alpha}-independent manner. -- Abstract: An increased level of plasminogen activator inhibitor-1 (PAI-1) is considered a risk factor for cardiovascular diseases, and PAI-1 gene expression is under the control of molecular circadian clocks in mammals. We recently showed that PAI-1 expression is augmented in a phase-advanced circadian manner in mice fed with a ketogenic diet (KD). To determine whether peroxisome proliferator-activated receptor {alpha} (PPAR{alpha}) is involved in hypofibrinolytic status induced by a KD, we examined the expression profiles of PAI-1 and circadian clock genes in PPAR{alpha}-null KD mice. Chronic administration of bezafibrate induced the PAI-1 gene expression in a PPAR{alpha}-dependent manner. Feeding with a KD augmented the circadian expression of PAI-1 mRNA in the hearts and livers of wild-type (WT) mice as previously described. The KD-induced mRNA expression of typical PPAR{alpha} target genes such as Cyp4A10 and FGF21 was damped in PPAR{alpha}-null mice. However, plasma PAI-1 concentrations were significantly more elevated in PPAR{alpha}-null KD mice in accordance with hepatic mRNA levels. These observations suggest that PPAR{alpha} activation is dispensable for KD-induced PAI-1 expression. We also found that hyperlipidemia, fatty liver, and the hepatic expressions of PPAR{gamma} and its coactivator PCG-1{alpha} were more effectively induced in PPAR{alpha}-null, than in WT mice on a KD. Furthermore, KD-induced hepatic PAI-1 expression was significantly suppressed by supplementation with bisphenol A diglycidyl ether, a PPAR{gamma} antagonist, in both WT and PPAR{alpha

alpha7 Nicotinic acetylcholine receptor knockout selectively enhances ethanol-, but not beta-amyloid-induced neurotoxicity.

Science.gov (United States)

de Fiebre, Nancyellen C; de Fiebre, Christopher M

2005-01-03

The alpha7 subtype of nicotinic acetylcholine receptor (nAChR) has been implicated as a potential site of action for two neurotoxins, ethanol and the Alzheimer's disease related peptide, beta-amyloid. Here, we utilized primary neuronal cultures of cerebral cortex from alpha7 nAChR null mutant mice to examine the role of this receptor in modulating the neurotoxic properties of subchronic, "binge" ethanol and beta-amyloid. Knockout of the alpha7 nAChR gene selectively enhanced ethanol-induced neurotoxicity in a gene dosage-related fashion. Susceptibility of cultures to beta-amyloid induced toxicity, however, was unaffected by alpha7 nAChR gene null mutation. Further, beta-amyloid did not inhibit the binding of the highly alpha7-selective radioligand, [(125)I]alpha-bungarotoxin. On the other hand, in studies in Xenopus oocytes ethanol efficaciously inhibited alpha7 nAChR function. These data suggest that alpha7 nAChRs modulate the neurotoxic effects of binge ethanol, but not the neurotoxicity produced by beta-amyloid. It is hypothesized that inhibition of alpha7 nAChRs by ethanol provides partial protection against the neurotoxic properties of subchronic ethanol.

Investigation of the Pygmy Dipole Resonance in (alpha, alpha 'gamma) coincidence experiments

NARCIS (Netherlands)

Savran, D.; Babilon, M.; van den Berg, A. M.; Harakeh, M. N.; Hasper, J.; Wortche, H. J.; Zilges, A.

2007-01-01

We report on first results from experiments using the (alpha, alpha'gamma) reaction at E alpha = 136 MeV to investigate bound electric dipole (El) excitations building the so-called Pygmy Dipole Resonance (PDR) in the semi-magic nucleus Ce-140. The method of (alpha, alpha'gamma) allows the

Light charged particle production in fast neutron-induced reactions on carbon (En=40 to 75 MeV) (II). Tritons and alpha particles

International Nuclear Information System (INIS)

Dufauquez, C.; Slypen, I.; Benck, S.; Meulders, J.P.; Corcalciuc, V.

2000-01-01

Double-differential cross sections for fast neutron-induced triton and alpha-particle production on carbon are reported at six incident neutron energies between 40 and 75 MeV. Angular distributions were measured at laboratory angles between 20 deg. and 160 deg. . Energy-differential, angle-differential and total cross sections are also reported. Experimental cross sections are compared to existing experimental data and to theoretical model calculations

Inhibition of TNF-alpha production contributes to the attenuation of LPS-induced hypophagia by pentoxifylline.

Science.gov (United States)

Porter, M H; Hrupka, B J; Altreuther, G; Arnold, M; Langhans, W

2000-12-01

Cytokines such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) are assumed to mediate anorexia during bacterial infections. To improve our understanding of the role that these two cytokines serve in mediating infection during anorexia, we investigated the ability of pentoxifylline (PTX), a potent inhibitor of TNF-alpha production, to block the anorectic effects of the bacterial products lipopolysaccharide (LPS) and muramyl dipeptide (MDP) in rats. Intraperitoneally injected PTX (100 mg/kg body wt) completely eliminated the anorectic effect of intraperitoneally injected LPS (100 microg/kg body wt) and attenuated the anorectic effect of a higher dose of intraperitoneally injected LPS (250 microg/kg body wt). Concurrently, PTX pretreatment suppressed low-dose LPS-induced TNF-alpha production by more than 95% and IL-1beta production 39%, as measured by ELISA. Similarly, high-dose LPS-induced TNF-alpha production was reduced by approximately 90%. PTX administration also attenuated the tolerance that is normally observed with a second injection of LPS. In addition, PTX pretreatment attenuated the hypophagic effect of intraperitoneally injected MDP (2 mg/kg body wt) but had no effect on the anorectic response to intraperitoneally injected recombinant human TNF-alpha (150 ug/kg body wt). The results suggest that suppression of TNF-alpha production is sufficient to attenuate LPS- and MDP-induced anorexia. This is consistent with the hypothesis that TNF-alpha plays a major role in the anorexia associated with bacterial infection.

Estrogen increases smooth muscle expression of alpha2C-adrenoceptors and cold-induced constriction of cutaneous arteries.

Science.gov (United States)

Eid, A H; Maiti, K; Mitra, S; Chotani, M A; Flavahan, S; Bailey, S R; Thompson-Torgerson, C S; Flavahan, N A

2007-09-01

Raynaud's phenomenon, which is characterized by intense cold-induced constriction of cutaneous arteries, is more common in women compared with men. Cold-induced constriction is mediated in part by enhanced activity of alpha(2C)-adrenoceptors (alpha(2C)-ARs) located on vascular smooth muscle cells (VSMs). Experiments were therefore performed to determine whether 17beta-estradiol regulates alpha(2C)-AR expression and function in cutaneous VSMs. 17beta-Estradiol (0.01-10 nmol/l) increased expression of the alpha(2C)-AR protein and the activity of the alpha(2C)-AR gene promoter in human cultured dermal VSMs, which was assessed following transient transfection of the cells with a promoter-reporter construct. The effect of 17beta-estradiol was associated with increased accumulation of cAMP and activation of the cAMP-responsive Rap2 GTP-binding protein. Transient transfection of VSMs with a dominant-negative mutant of Rap2 inhibited the 17beta-estradiol-induced activation of the alpha(2C)-AR gene promoter, whereas a constitutively active mutant of Rap2 increased alpha(2C)-AR promoter activity. The effects of 17beta-estradiol were inhibited by the estrogen receptor (ER) antagonist, ICI-182780 (1 micromol/l), and were mimicked by a cell-impermeable form of the hormone (estrogen:BSA) or by the selective ER-alpha receptor agonist 4,4',4'''-(4-propyl-[(1)H]-pyrazole-1,3,5-triyl)tris-phenol (PPT; 10 nmol/l) or the selective ER-beta receptor agonist 2,3-bis(4-hydroxyphenyl)-propionitrile (DPN; 10 nmol/l). Therefore, 17beta-estradiol increased expression of alpha(2C)-ARs by interacting with cell surface receptors to cause a cAMP/Rap2-dependent increase in alpha(2C)-AR transcription. In mouse tail arteries, 17beta-estradiol (10 nmol/l) increased alpha(2C)-AR expression and selectively increased the cold-induced amplification of alpha(2)-AR constriction, which is mediated by alpha(2C)-ARs. An estrogen-dependent increase in expression of cold-sensitive alpha(2C)-ARs may contribute

Averaged currents induced by alpha particles in an InSb compound semiconductor detector

International Nuclear Information System (INIS)

Kanno, Ikuo; Hishiki, Shigeomi; Kogetsu, Yoshitaka; Nakamura, Tatsuya; Katagiri, Masaki

2008-01-01

Very fast pulses due to alpha particle incidence were observed by an undoped-type InSb Schottky detector. This InSb detector was operated without applying bias voltage and its depletion layer thickness was less than the range of alpha particles. The averaged current induced by alpha particles was analyzed as a function of operating temperature and was shown to be proportional to the Hall mobility of InSb. (author)

Charged-particle magnetic-quadrupole spectrometer for neutron induced reactions

International Nuclear Information System (INIS)

Haight, R.C.; Grimes, S.M.; Tuckey, B.J.; Anderson, J.D.

1975-01-01

A spectrometer has been developed for measuring the charged particle production cross sections and spectra in neutron-induced reactions. The spectrometer consists of a magnetic quadrupole doublet which focuses the charged particles onto a silicon surface barrier detector telescope which is 2 meters or more from the irradiated sample. Collimators, shielding, and the large source-to-detector distance reduce the background enough to use the spectrometer with a 14-MeV neutron source producing 4 . 10 12 n/s. The spectrometer has been used in investigations of proton, deuteron, and alpha particle production by 14-MeV neutrons incident on various materials. Protons with energies as low as 1.1 MeV have been measured. The good resolution of the detectors has also made possible an improved measurement of the neutron- neutron scattering length from the 0 0 proton spectrum from deuteron breakup by 14-MeV neutrons

Heavy-ion induced multinucleon transfer reactions in the 2s--1d shell

International Nuclear Information System (INIS)

Olmer, C.

1975-01-01

In order to investigate whether new nuclear structure information can be obtained from studying the direct transfer of more than two nucleons using heavy-ion projectiles, we have investigated the 28 Si( 16 O, 12 C) 32 S and 12 C( 14 N,d) 24 Mg reactions as candidates for the direct transfer of four- and twelve-nucleons, respectively. The counter telescope-position sensitive detector kinematic coincidence method--both angular distributions (22 0 less than theta/sub L/ less than 95 0 , E/sub L/ = 55.54 MeV) and excitation functions (theta/sub L/ = 26 0 , 50 less than E/sub L/ less than 63 MeV) were obtained for strongly excited states below 10 MeV in excitation in the first reaction. For the 12 C + 14 N interaction, a measurement of the angular distributions (25 0 less than theta/sub L/ less than 140 0 , E/sub L/ = 20,25 MeV) for proton, deuteron and alpha-particle emission to many low-lying states sufficed for the present purposes. Comparison of Hauser-Feshbach statistical model calculations with these data indicated that the light-particle production from the 12 C + 14 N interaction as investigated here is predominantly compound nuclear in nature. The selectively strong population of a few states in 32 S by the 28 Si-( 16 O, 12 C) 32 S reaction is primarily direct. The structure of these states was deduced from available light-ion-induced transfer reaction studies and shell model calculations; the importance of shell model configurations is indicated, and an alpha-particle transfer model can not account for the observed selectivity. Calculations of the 28 Si( 16 O, 12 C) 32 S reaction with a microscopic multinucleon transfer code indicate selectivities consistent with the present results. Moreover, the calculations suggest the presence of other, unexpected selectivities, all of which may be understood on a physical basis, and some of which appear as an extension of a similar effect seen in two-nucleon transfer reactions

Contribution to the study of {sup 12}C excited levels resulting from the reactions {sup 11}B (P/ {alpha}{sub 0}) and {sup 11}B (p, {alpha}{sub 1}); Contribution a l'etude des niveaux excites du {sup 12}C obtenus par les reactions {sup 11}B (p, {alpha}{sub 0}) et {sup 11}B (p, {alpha}{sub l})

Energy Technology Data Exchange (ETDEWEB)

Longequeue, J P [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1963-11-15

This work is made up of two parts. In the first part the differential cross-sections have been determined of the reactions {sup 11}B (p,{alpha}) from 130 to 500 keV thus confirming, at the 163 keV resonance, the (2{sup +}) characteristics of the 16.11 MeV level of {sup 12}C. Furthermore, the experimental results in the neighbourhood of the 163 keV resonance can be explained by the interference of the {sup 12}C levels: 2{sup +} at 16.11 MeV and 1{sup -} at 17.23 MeV for the {alpha}{sub 0}, 2{sup +} at 16.11 MeV and 2{sup -} at 16.58 MeV for the {alpha}{sub 1}. In the second part the ({alpha}{sup -8Be}) disintegration process of {sup 12}C has been studied in the neighbourhood of the 16.11 MeV level. It is shown that, if the ({alpha}{sup -8Be}) mode of disintegration is preponderant outside the E{sub p} = 163 keV resonance, it is also preponderant at this same resonance; a direct disintegration of the {sup 12}C to 3 {alpha}, with an approximate magnitude of 40 per cent has however not been excluded. (author) [French] Ce travail comprend deux parties: Dans la premiere, on a determine la section efficace differentielle des reactions {sup 11}B (p,{alpha}) de 130 a 500 keV, confirmant, a la resonance de 163 keV, les caracteristiques (2{sup +}) du niveau de 16,11 MeV du {sup 12}C. En outre, les resultats experimentaux au voisinage de la resonance de 163 keV sont explicables par l'interference des niveaux du {sup 12}C: 2{sup +} a 16,11 MeV et 1{sup -} a 17,23 MeV pour les {alpha}{sub 0}, 2{sup +} a 16,11 MeV et 2{sup -} a 16,58 MeV pour les {alpha}{sub 1}. Dans la deuxieme partie, on a etudie le mode de desintegration ({alpha}{sup -8Be}) du {sup 12}C au voisinage du niveau de 16,11 MeV. On a montre que, si le mode de desintegration ({alpha}{sup -8Be}) est preponderant en dehors de la resonance E{sub p} = 163 keV, il est egalement preponderant a cette resonance; une desintegration directe en 3{alpha} du {sup 12}C, dont l'ordre de grandeur maximum serait de 40 pour cent, n

Investigations of (. cap alpha. ,. cap alpha. 'x) reactions up to 40 MeV/A bombarding energy

Energy Technology Data Exchange (ETDEWEB)

Machner, H [Kernforschungsanlage Juelich G.m.b.H. (Germany, F.R.). Inst. fuer Kernphysik; Feldmeier, H [ed.

1980-02-01

The angle integrated cross sections of continuous nucleon spectra from light ion induced reactions could be well reproduced within nonequilibrium statistical models. An extended exciton model even allows the calculations of angular distributions. Energy and linear momentum dissipation are treated with the help of a generalized master equation. The Exciton Coalescence Model (ECM) reproduces the angular distributions of complex particles emitted in nuclear reactions at moderate energies.

The Effect of Nigella Sativa Extract on Alpha-ketoglutarate Activity and Histopathologic Changes on Rat Liver Induced by Monosodium Glutamate

Directory of Open Access Journals (Sweden)

Ala Sh Emhemed Eshami

2015-09-01

Full Text Available Monosodium glutamate (MSG is a commonly used food additive and found in most soups, fish, and processed meat. The use of MSG in food is growing. However, the fear of consuming MSG has increased in the last few years due to the adverse reactions and toxicity in the liver. Nigella sativa (NS is used as traditional medicine for the treatment of many diseases. It has been extensively investigated in recent years due to its notable pharmacological properties such as inhibit oxidative stress. The present study was undertaken to investigate the effect of different doses of Nigella Sativa on alpha KGDH activity and liver histology of MSG-induced rats. The animals (n=30 were grouped into A (control, B (treated with MSG 1g/kg.bw , C (treated with MSG 1g/kg.bw and NS 0.1 g/kg.bw, D (treated with MSG 1g/kg.bw and NS 0.2 g/kg.bw, E (treated with MSG 1g/kg.bw and NS 0.4 g/kg.bw and F (given a daily NS extract 0.2 g/kg.bw. Alpha KGDH activity was investigated using ELISA method and liver histopathology by light microscope. The MSG treatment increased Alpha KGDH activity and disturbed liver architecture, hemorrhage in the central veins, areas of necrosis, vacuolation and increased inflammatory cells infiltration. The condition was normalized by treatment NS on dose 0.2 and 0.4 g/kg.bw. The findings showed that the administration of MSG increases alpha KGDH and induces damage in liver tissue. Nigella sativa extract can reduce alpha KGDH and prevent liver damage caused by MSG.

Mechanistic and kinetic insights into the thermally induced rearrangement of alpha-pinene.

Science.gov (United States)

Stolle, Achim; Ondruschka, Bernd; Findeisen, Matthias

2008-11-07

The thermal rearrangement of alpha-pinene (1) is interesting from mechanistic as well as kinetic point of view. Carrier gas pyrolyses with 1 and its acyclic isomers ocimene (2) and alloocimene (3) were performed to investigate the thermal network of these hydrocarbons. Kinetic analysis of the major reaction steps allows for a deeper insight in the reaction mechanism. Thus it was possible to explain the racemization of 1, the formation of racemic limonene (4), and the absence of the primary pyrolysis product 2 in the reaction mixture resulting from thermal rearrangement of 1. Results supported the conclusion that the reactions starting with 1 involve biradical transition states.

Nuclear Astrophysics and Neutron Induced Reactions: Quasi-Free Reactions and RIBs

International Nuclear Information System (INIS)

Cherubini, S.; Spitaleri, C.; Crucilla, V.; Gulino, M.; La Cognata, M.; Lamia, L.; Pizzone, R. G.; Puglia, S.; Rapisarda, G. G.; Romano, S.; Sergi, M. L.; Coc, A.; Kubono, S.; Binh, D. N.; Hayakawa, S.; Wakabayashi, Y.; Yamaguchi, H.; Burjan, V.; Kroha, V.; De Sereville, N.

2010-01-01

The use of quasi-free reactions in studying nuclear reactions between charged particles of astrophysical interest has received much attention over the last two decades. The Trojan Horse Method is based on this approach and it has been used to study a number of reactions relevant for Nuclear Astrophysics. Recently we applied this method to the study of nuclear reactions that involve radioactive species, namely to the study of the 18 F+p→ 15 O+α process at temperatures corresponding to the energies available in the classical novae scenario. Quasi-free reactions can also be exploited to study processes induced by neutrons. This technique is particularly interesting when applied to reaction induced by neutrons on unstable short-lived nuclei. Such processes are very important in the nucleosynthesis of elements in the sand r-processes scenarios and this technique can give hints for solving key questions in nuclear astrophysics where direct measurements are practically impossible.

Inhibition of HIF-1{alpha} activity by BP-1 ameliorates adjuvant induced arthritis in rats

Energy Technology Data Exchange (ETDEWEB)

Shankar, J. [Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago (United States); Thippegowda, P.B., E-mail: btprabha@uic.edu [Department of Pharmacology, (M/C 868), College of Medicine, University of Illinois at Chicago, 835 S. Wolcott Ave., Chicago, IL 60612 (United States); Kanum, S.A. [Department of Chemistry, Yuvaraj' s College, University of Mysore, Mysore (India)

2009-09-18

Rheumatoid arthritis (RA) is a chronic inflammatory, angiogenic disease. Inflamed synovitis is a hallmark of RA which is hypoxic in nature. Vascular endothelial growth factor (VEGF), one of the key regulators of angiogenesis, is overexpressed in the pathogenesis of RA. VEGF expression is regulated by hypoxia-inducible factor-1{alpha} (HIF-1{alpha}), a master regulator of homeostasis which plays a pivotal role in hypoxia-induced angiogenesis. In this study we show that synthetic benzophenone analogue, 2-benzoyl-phenoxy acetamide (BP-1) can act as a novel anti-arthritic agent in an experimental adjuvant induced arthritis (AIA) rat model by targeting VEGF and HIF-1{alpha}. BP-1 administered hypoxic endothelial cells and arthritic animals clearly showed down regulation of VEGF expression. Further, BP-1 inhibits nuclear translocation of HIF-1{alpha}, which in turn suppresses transcription of the VEGF gene. These results suggest a further possible clinical application of the BP-1 derivative as an anti-arthritic agent in association with conventional chemotherapeutic agents.

Quasi-bound alpha resonant states populated by the {sup 12}C({sup 6}Li, d) reaction

Energy Technology Data Exchange (ETDEWEB)

Rodrigues, M.R.D.; Borello-Lewin, T.; Miyake, H.; Horodynski-Matsushigue, L.B.; Duarte, J.L.M.; Rodrigues, C.L.; Souza, M.A. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica; Cunsolo, A.; Cappuzzello, F.; Foti, A.; Agodi, C.; Cavallaro, M. [Istituto Nazionale di Fisica Nucleare (LNS/INFN), Catania (Italy). Lab. Nazionali del Sud; Ukita, G.M. [Universidade de Santo Amaro (UNISA), Sao Paulo, SP (Brazil). Faculdade de Psicologia

2012-07-01

Full text: The alpha cluster phenomenon in the light nuclei structure has been the subject of a long time investigation since the proposal of the Ikeda diagrams [1]. The main purpose of the research program in progress is the investigation of this phenomenon in (x{alpha}) and (x{alpha}+n) nuclei through the ({sup 6}Li, d) alpha transfer reaction [2-4]. Alpha resonant states around the (4{alpha}) threshold in the nucleus {sup 16}O are the focus of the present contribution. In fact, the importance of these resonances at the elements production in stars is recognized, as primarily pointed out by Hoyle in {sup 12}C [6]. The existence of a rotational band with the {alpha} +{sup 12} C (Hoyle) cluster state structure was recently demonstrated by Ohkubo and Hirabayashi [6]. In order to explore this region of interest, measurements of the {sup 12}C({sup 6}Li, d){sup 16}O reaction up to 17 MeV of excitation at an incident energy of 25.5 MeV, have been performed employing the Sao Paulo Pelletron-Enge Split-Pole facility and the nuclear emulsion detection technique (plates Fuji G6B, 50 {mu}m thick). Spectra associated with six scattering angles, from 5 deg to 29 deg in the laboratory frame, each one 50 cm along the focal surface, were measured. Several narrow resonances with a quasi-bound behavior embedded in the continuum were detected and the resolution of 25 keV allowed for the separation of doublets not resolved before [7,8]. The absolute cross sections and the respective deuteron angular distributions were determined and the analysis is in progress. [1] K. Ikeda et al., Prog. Theor. Phys. Suppl. E 68, 464 (1968); H. Horiuchi, K. Ikeda, and Y. Suzuki, ibid. 44, 225 (1978). [2] M.R.D.Rodrigues et al., in12th International Conference on Nuclear Reaction Mechanism, Varenna, Italy, edited by F. Cerutti and A. Ferrari , CERN Proceedings, 2010-2, pp. 331- 335. [3] T. Borello-Lewin et al., Proceedings of SOTANCP2, Brussels, Belgium 2010, edited by P. Descouvemount et al., Int. J

Separation of reaction mechanisms at low energy. Study of the reactions: {sup 27}Al(d,p) {sup 28}Al, {sup 24}Mg(d,p) {sup 25}Mg, and {sup 24}Mg(d, {alpha}) {sup 22}Na; Sur la separation des mecanismes de reaction a basse energie. Etude des reactions: {sup 27}Al(d,p) {sup 28}Al, {sup 24}Mg(d,p) {sup 25}Mg, et {sup 24}Mg(d, {alpha}) {sup 22}Na

Energy Technology Data Exchange (ETDEWEB)

Mermaz, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1966-06-01

The two sets of angular distributions of (d,p) reactions on Al and Mg, measured between 2 and 6 MeV, have given the possibility to test, in analysing the statistical fluctuations of cross-section, the validity of the separation of their mean values in two parts, one 'direct', another given by the statistical mechanism. With the same method of analysis we have studied excitation functions for several alpha groups of the reaction {sup 24}Mg(d, {alpha}) {sup 22}Na and given an evidence for an intermediate structure for the alpha channel leading to the 3. excited state of {sup 22}Na. The angular distribution of the wide resonance at 15.9 MeV in {sup 26}Al has been obtained. (author) [French] Les deux ensembles de distributions angulaires des reactions (d,p) sur Al et Mg, mesures entre 2 et 6 MeV, nous ont permis, en analysant les fluctuations statistiques de sections efficaces, de verifier la possibilite de la separation de leurs valeurs moyennes en deux composantes: l'une 'directe', l'autre due au mecanisme statistique. Avec la meme methode d'analyse nous avons etudie les fonctions d'excitation des premiers groupes alpha de la reaction {sup 24}Mg(d,{alpha}) {sup 22}Na et mis en evidence une structure intermediaire pour la voie de reaction aboutissant au 3eme niveau de {sup 22}Na. Nous avons obtenu la distribution angulaire de la resonance large situee a une energie d'excitation de 15,9 MeV dans {sup 26}Al. (auteur)

Separation of reaction mechanisms at low energy. Study of the reactions: {sup 27}Al(d,p) {sup 28}Al, {sup 24}Mg(d,p) {sup 25}Mg, and {sup 24}Mg(d, {alpha}) {sup 22}Na; Sur la separation des mecanismes de reaction a basse energie. Etude des reactions: {sup 27}Al(d,p) {sup 28}Al, {sup 24}Mg(d,p) {sup 25}Mg, et {sup 24}Mg(d, {alpha}) {sup 22}Na

Energy Technology Data Exchange (ETDEWEB)

Mermaz, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1966-06-01

The two sets of angular distributions of (d,p) reactions on Al and Mg, measured between 2 and 6 MeV, have given the possibility to test, in analysing the statistical fluctuations of cross-section, the validity of the separation of their mean values in two parts, one 'direct', another given by the statistical mechanism. With the same method of analysis we have studied excitation functions for several alpha groups of the reaction {sup 24}Mg(d, {alpha}) {sup 22}Na and given an evidence for an intermediate structure for the alpha channel leading to the 3. excited state of {sup 22}Na. The angular distribution of the wide resonance at 15.9 MeV in {sup 26}Al has been obtained. (author) [French] Les deux ensembles de distributions angulaires des reactions (d,p) sur Al et Mg, mesures entre 2 et 6 MeV, nous ont permis, en analysant les fluctuations statistiques de sections efficaces, de verifier la possibilite de la separation de leurs valeurs moyennes en deux composantes: l'une 'directe', l'autre due au mecanisme statistique. Avec la meme methode d'analyse nous avons etudie les fonctions d'excitation des premiers groupes alpha de la reaction {sup 24}Mg(d,{alpha}) {sup 22}Na et mis en evidence une structure intermediaire pour la voie de reaction aboutissant au 3eme niveau de {sup 22}Na. Nous avons obtenu la distribution angulaire de la resonance large situee a une energie d'excitation de 15,9 MeV dans {sup 26}Al. (auteur)

Alpha particles induce expression of immunogenic markers on tumour cells

International Nuclear Information System (INIS)

Gorin, J.B.; Gouard, S.; Cherel, M.; Davodeau, F.; Gaschet, J.; Morgenstern, A.; Bruchertseifer, F.

2013-01-01

The full text of the publication follows. Radioimmunotherapy (RIT) is an approach aiming at targeting the radioelements to tumours, usually through the use of antibodies specific for tumour antigens. The radiations emitted by the radioelements then induce direct killing of the targeted cells as well as indirect killing through bystander effect. Interestingly, it has been shown that ionizing radiations, in some settings of external radiotherapy, can foster an immune response directed against tumour cells. Our research team is dedicated to the development of alpha RIT, i.e RIT using alpha particle emitters, we therefore decided to study the effects of such particles on tumour cells in regards to their immunogenicity. First, we studied the effects of bismuth 213, an alpha emitter, on cellular death and autophagy in six different tumour cell lines. Then, we measured the expression of 'danger' signals and MHC molecules at the cell surface to determine whether irradiation with 213 Bi could cause the tumour cells to be recognized by the immune system. Finally a co-culture of dendritic cells with irradiated tumour cells was performed to test whether it would induce dendritic cells to mature. No apoptosis was detected within 48 hours after irradiation in any cell line, however half of them exhibited signs of autophagy. No increase in membrane expression of 'danger' signals was observed after treatment with 213 Bi, but we showed an increase in expression of MHC class I and II for some cell lines. Moreover, the co-culture experiment indicated that the immunogenicity of a human adenocarcinoma cell line (LS 174T) was enhanced in vitro after irradiation with alpha rays. These preliminary data suggest that alpha particles could be of interest in raising an immune response associated to RIT. (authors)

Interaction of alpha radiation with thermally-induced defects in silicon

International Nuclear Information System (INIS)

Ali, Akbar; Majid, Abdul

2008-01-01

The interaction of radiation-induced defects created by energetic alpha particles and thermally-induced defects in silicon has been studied using a Deep Level Transient Spectroscopy (DLTS) technique. Two thermally-induced defects at energy positions E c -0.48 eV and E c -0.25 eV and three radiation-induced defects E2, E3 and E5 have been observed. The concentration of both of the thermally-induced defects has been observed to increase on irradiation. It has been noted that production rates of the radiation-induced defects are suppressed in the presence of thermally-induced defects. A significant difference in annealing characteristics of thermally-induced defects in the presence of radiation-induced defects has been observed compared to the characteristics measured in pre-irradiated samples

Examination and experimental constraints of the stellar reaction rate factor N-A of the Ne-18(alpha, p)Na-21 reaction at temperatures of x-ray bursts

NARCIS (Netherlands)

Matic, A.; Mohr, P.

2013-01-01

The Ne-18(alpha, p)Na-21 reaction is one key for the breakout from the hot CNO cycles to the rp-process. Recent papers have provided reaction rate factors N-A which are discrepant by at least one order of magnitude. The compatibility of the latest experimental results is tested, and a partial

17-AAG induces cytoplasmic alpha-synuclein aggregate clearance by induction of autophagy.

Science.gov (United States)

Riedel, Michael; Goldbaum, Olaf; Schwarz, Lisa; Schmitt, Sebastian; Richter-Landsberg, Christiane

2010-01-18

The accumulation and aggregation of alpha-synuclein in nerve cells and glia are characteristic features of a number of neurodegenerative diseases termed synucleinopathies. alpha-Synuclein is a highly soluble protein which in a nucleation dependent process is capable of self-aggregation. The causes underlying aggregate formation are not yet understood, impairment of the proteolytic degradation systems might be involved. In the present study the possible aggregate clearing effects of the geldanamycin analogue 17-AAG (17-(Allylamino)-17-demethoxygeldanamycin) was investigated. Towards this, an oligodendroglial cell line (OLN-93 cells), stably expressing human alpha-synuclein (A53T mutation) was used. In these cells small punctate aggregates, not staining with thioflavine S, representing prefibrillary aggregates, occur characteristically. Our data demonstrate that 17-AAG attenuated the formation of alpha-synuclein aggregates by stimulating macroautophagy. By blocking the lysosomal compartment with NH(4)Cl the aggregate clearing effects of 17-AAG were abolished and alpha-synuclein deposits were enlarged. Analysis of LC3-II immunoreactivity, which is an indicator of autophagosome formation, further revealed that 17-AAG led to the recruitment of LC3-II and to the formation of LC3 positive puncta. This effect was also observed in cultured oligodendrocytes derived from the brains of newborn rats. Inhibition of macroautophagy by 3-methyladenine prevented 17-AAG induced occurrence of LC3 positive puncta as well as the removal of alpha-synuclein aggregates in OLN-A53T cells. Our data demonstrate for the first time that 17-AAG not only causes the upregulation of heat shock proteins, but also is an effective inducer of the autophagic pathway by which alpha-synuclein can be removed. Hence geldanamycin derivatives may provide a means to modulate autophagy in neural cells, thereby ameliorating pathogenic aggregate formation and protecting the cells during disease and aging.

Application of evaporation model to the calculation of energy spectrum and angular distribution of recoil nuclei from neutron induced reaction

Energy Technology Data Exchange (ETDEWEB)

Takeda, Y; Sugimoto, M; Sugiyama, K [Tohoku Univ., Sendai (Japan). Faculty of Engineering

1978-12-01

Calculated angular distributions and energy spectra from 14.8 MeV neutron induced (n,2n) reactions based on a simple evaporation model were obtained by means of the Monte Carlo method. It was ascertained that the effects on the spectra of the method of determining the nuclear temperature and the value of the level density parameter are much smaller than those of the reaction Q-value and the nuclear mass. As a check on the calculational procedure, results of similar calculations were compared with the experimental recoil escape efficiency for /sup 27/Al(n,..cap alpha..)/sup 24/Na reaction. Distortions of the energy spectra in thick target materials were also obtained. These results suggest that this model is fully applicable to the calculation of primary knock-on atoms distributions from various nuclear reactions.

Photon hormesis deactivates alpha-particle induced bystander effects between zebrafish embryos

International Nuclear Information System (INIS)

Ng, C.Y.P.; Cheng, S.H.; Yu, K.N.

2017-01-01

In the present work, we studied the effects of low-dose X-ray photons on the alpha-particle induced bystander effects between embryos of the zebrafish, Danio rerio. The effects on the naive whole embryos were studied through quantification of apoptotic signals (amounts of cells undergoing apoptosis) at 24 h post fertilization (hpf) using vital dye acridine orange staining, followed by counting the stained cells under a fluorescent microscope. We report data showing that embryos at 5 hpf subjected to a 4.4 mGy alpha-particle irradiation could release a stress signal into the medium, which could induce bystander effect in partnered naive embryos sharing the same medium. We also report that the bystander effect was deactivated when the irradiated embryos were subjected to a concomitant irradiation of 10 or 14 mGy of X-rays, but no such deactivation was achieved if the concomitant X-ray dose dropped to 2.5 or 5 mGy. In the present study, the significant drop in the amount of apoptotic signals on the embryos having received 4.4 mGy alpha particles together X-rays irradiation from 2.5 or 5 mGy to 10 or 14 mGy, together with the deactivation of RIBE with concomitant irradiation of 10 or 14 mGy of X-rays supported the participation of photon hormesis with an onset dose between 5 and 10 mGy, which might lead to removal of aberrant cells through early apoptosis or induction of high-fidelity DNA repair. As we found that photons and alpha particles could have opposite biological effects when these were simultaneously irradiated onto living organisms, these ionizing radiations could be viewed as two different environmental stressors, and the resultant effects could be regarded as multiple stressor effects. The present work presented the first study on a multiple stressor effect which occurred on bystander organisms. In other words, this was a non-targeted multiple stressor effect. The photon hormesis could also explain some failed attempts to observe neutron-induced bystander

Studying effects of Magnolol on alpha-particle induced bystander effects using PADC-film based dishes

Energy Technology Data Exchange (ETDEWEB)

Wong, T.P.W. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong); Tse, A.K.W.; Fong, W.F. [Research and Development Division, School of Chinese Medicine, Hong Kong Baptist University, Baptist University Road, Kowloon Tong (Hong Kong); Yu, K.N., E-mail: peter.yu@cityu.edu.h [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong)

2009-10-15

Radiation-induced bystander effect refers to the biological response found in cells (called bystander cells) which are not irradiated directly by ionizing radiation but are next to cells irradiated directly by ionizing radiation. In the present paper, the effects of Magnolol, an extract from the bark of Magnolia officinalis which is used as a traditional Chinese medicine, were studied on alpha-particle induced bystander effects. In our experiments, Chinese hamster ovary (CHO) cells were cultured in PADC-film based dishes and were irradiated with low fluences of alpha particles passing through the PADC films. The precise number of cells traversed or missed by alpha particles could be determined by studying the alpha-particle tracks developed on the PADC films upon subsequent chemical etching. TdT-mediated dUTP Nick-End Labeling (TUNEL) assay was employed to analyze the biological response of bystander cells in terms of DNA strand breaks. With the pretreatment of Magnolol, the DNA strand breaks in bystander cells were reduced, which showed that the alpha-particle induced bystander effects were suppressed with the presence of Magnolol. Since Magnolol is an antioxidant which can scavenge reactive oxygen species (ROS), our results give support to that ROS play a role in the bystander signal transmission in our experiments.

Studying effects of Magnolol on alpha-particle induced bystander effects using PADC-film based dishes

International Nuclear Information System (INIS)

Wong, T.P.W.; Tse, A.K.W.; Fong, W.F.; Yu, K.N.

2009-01-01

Radiation-induced bystander effect refers to the biological response found in cells (called bystander cells) which are not irradiated directly by ionizing radiation but are next to cells irradiated directly by ionizing radiation. In the present paper, the effects of Magnolol, an extract from the bark of Magnolia officinalis which is used as a traditional Chinese medicine, were studied on alpha-particle induced bystander effects. In our experiments, Chinese hamster ovary (CHO) cells were cultured in PADC-film based dishes and were irradiated with low fluences of alpha particles passing through the PADC films. The precise number of cells traversed or missed by alpha particles could be determined by studying the alpha-particle tracks developed on the PADC films upon subsequent chemical etching. TdT-mediated dUTP Nick-End Labeling (TUNEL) assay was employed to analyze the biological response of bystander cells in terms of DNA strand breaks. With the pretreatment of Magnolol, the DNA strand breaks in bystander cells were reduced, which showed that the alpha-particle induced bystander effects were suppressed with the presence of Magnolol. Since Magnolol is an antioxidant which can scavenge reactive oxygen species (ROS), our results give support to that ROS play a role in the bystander signal transmission in our experiments.

Differential cross section measurements for the 6Li(n,t)alpha reaction in the few MeV region

Energy Technology Data Exchange (ETDEWEB)

Devlin, Matthew J [Los Alamos National Laboratory; Taddeucci, Terence N [Los Alamos National Laboratory; Hale, Gerald M [Los Alamos National Laboratory; Haight, Robert C [Los Alamos National Laboratory; O' Donnell, Johhn M [Los Alamos National Laboratory

2008-01-01

New measured differential cross sections of tritons and alpha particles following the {sup 6}Li(n,t){alpha} reaction are reported for incident neutron energies between 0.2 and approximately 20 MeV. The neutrons were produced by spallation at the WNR facility at the Los Alamos Neutron Science CEnter (LANSCE), with the incident neutron energy determined by the time-of-flight method. Four E-{Delta}E telescopes were used at eight laboratory angles. These data have been incorporated into a prior R-matrix fit for the compound {sup 7}Li system, and result in an (n,t) reaction cross section that is 4% to 10% higher than previous evaluations in the 1-3 MeV incident neutron energy region.

Atomic force microscopic neutron-induced alpha-autoradiography for boron imaging in detailed cellular histology

International Nuclear Information System (INIS)

Amemiya, K.; Takahashi, H.; Fujita, K.; Nakazawa, M.; Yanagie, H.; Eriguchi, M.; Nakagawa, Y.; Sakurai, Y.

2006-01-01

The information on subcellular microdistribution of 10 B compounds a cell is significant to evaluate the efficacy of boron neutron capture therapy (BNCT) because the damage brought by the released alpha/lithium particles is highly localized along their path, and radiation sensitivity is quite different among each cell organelles. In neutron-induced alpha-autoradiography (NIAR) technique, 10 B can be measured as tracks for the energetic charged particles from 10 B(n, alpha) 7 Li reactions in solid state track detectors. To perform the NIAR at intracellular structure level for research of 10 B uptake and/or microdosimetry in BNCT, we have developed high-resolution NIAR method with an atomic force microscope (AFM). AFM has been used for analyses of biological specimens such as proteins, DNAs and surface of living cells have, however, intracellular detailed histology of cells has been hardly resolved with AFM since flat surface of sectioned tissue has quite less topographical contrast among each organelle. In our new sample preparation method using UV processing, materials that absorb UV in a semi-thin section are selectively eroded and vaporized by UV exposure, and then fine relief for cellular organelles such as mitochondria, endoplasmic reticulum, filament structure and so on reveals on flat surface of the section, which can be observed with an AFM. The imaging resolution was comparable to TEM imaging of cells. This new method provides fast and cost-effective observation of histological sections with an AFM. Combining this method with NIAR technique, intracellular boron mapping would be possible. (author)

Parity violation in neutron induced reactions

International Nuclear Information System (INIS)

Gudkov, V.P.

1991-06-01

The theory of parity violation in neutron induced reactions is discussed. Special attention is paid to the energy dependence and enhancement factors for the various types of nuclear reactions and the information which might be obtained from P-violating effects in nuclei. (author)

PGC-1alpha mediates exercise-induced skeletal muscle VEGF expression in mice

DEFF Research Database (Denmark)

Leick, Lotte; Hellsten, Ylva; Fentz, Joachim

2009-01-01

The aim of the present study was to test the hypothesis that PGC-1alpha is required for exercise-induced VEGF expression in both young and old mice and that AMPK activation leads to increased VEGF expression through a PGC-1alpha-dependent mechanism. Whole body PGC-1alpha knockout (KO......) and littermate wild-type (WT) mice were submitted to either 1) 5 wk of exercise training, 2) lifelong (from 2 to 13 mo of age) exercise training in activity wheel, 3) a single exercise bout, or 4) 4 wk of daily subcutaneous AICAR or saline injections. In skeletal muscle of PGC-1alpha KO mice, VEGF protein...... expression was approximately 60-80% lower and the capillary-to-fiber ratio approximately 20% lower than in WT. Basal VEGF mRNA expression was similar in WT and PGC-1alpha KO mice, but acute exercise and AICAR treatment increased the VEGF mRNA content in WT mice only. Exercise training of young mice increased...

Development of a chromosomally integrated metabolite-inducible Leu3p-alpha-IPM "off-on" gene switch.

Directory of Open Access Journals (Sweden)

Maria Poulou

2010-08-01

Full Text Available Present technology uses mostly chimeric proteins as regulators and hormones or antibiotics as signals to induce spatial and temporal gene expression.Here, we show that a chromosomally integrated yeast 'Leu3p-alpha-IotaRhoMu' system constitutes a ligand-inducible regulatory "off-on" genetic switch with an extensively dynamic action area. We find that Leu3p acts as an active transcriptional repressor in the absence and as an activator in the presence of alpha-isopropylmalate (alpha-IotaRhoMu in primary fibroblasts isolated from double transgenic mouse embryos bearing ubiquitously expressing Leu3p and a Leu3p regulated GFP reporter. In the absence of the branched amino acid biosynthetic pathway in animals, metabolically stable alpha-IPM presents an EC(50 equal to 0.8837 mM and fast "OFF-ON" kinetics (t(50ON = 43 min, t(50OFF = 2.18 h, it enters the cells via passive diffusion, while it is non-toxic to mammalian cells and to fertilized mouse eggs cultured ex vivo.Our results demonstrate that the 'Leu3p-alpha-IotaRhoMu' constitutes a simpler and safer system for inducible gene expression in biomedical applications.

Basic reactions induced by radiation

International Nuclear Information System (INIS)

Charlesby, A.

1980-01-01

This paper summarises some of the basic reactions resulting from exposure to high energy radiation. In the initial stages energy is absorbed, but not necessarily at random, giving radical and ion species which may then react to promote the final chemical change. However, it is possible to intervene at intermediate stages to modify or reduce the radiation effect. Under certain conditions enhanced reactions are also possible. Several expressions are given to calculate radiation yield in terms of energy absorbed. Some analogies between radiation-induced reactions in polymers, and those studied in radiobiology are outlined. (author)

The fluorine destruction in stars: First experimental study of the {sup 19}F(p,{alpha}){sup 16}O reaction at astrophysical energies

Energy Technology Data Exchange (ETDEWEB)

La Cognata, M.; Mukhamedzhanov, A.; Spitaleri, C.; Indelicato, I.; Aliotta, M.; Burjan, V.; Cherubini, S.; Coc, A.; Gulino, M.; Hons, Z.; Kiss, G. G.; Kroha, V.; Lamia, L.; Mrazek, J.; Palmerini, S.; Piskor, S.; Pizzone, R. G.; Puglia, S. M. R.; Rapisarda, G. G.; Romano, S. [INFN-LNS, Catania (Italy); Cyclotron Institute, Texas A and M University, College Station, Texas (United States); University of Catania and INFN-LNS, Catania (Italy); and others

2012-11-12

The {sup 19}F(p,{alpha}){sup 16}O reaction is an important fluorine destruction channel in the proton-rich outer layers of asymptotic giant branch (AGB) stars and it might also play a role in hydrogendeficient post-AGB star nucleosynthesis. So far, available direct measurements do not reach the energy region of astrophysical interest (E{sub cm}{approx} 300 keV), because of the hindrance effect of the Coulomb barrier. The Trojan Horse (TH) method was thus used to access this energy region, by extracting the quasi-free contribution to the {sup 2}H({sup 19}F,{alpha}{sup 16}O)n reaction. The TH measurement of the {alpha}{sub 0} channel, which is the dominant one at such energies, shows the presence of resonant structures not observed before that cause an increase of the reaction rate at astrophysical temperatures up to a factor of 1.7, with potential important consequences for stellar nucleosynthesis.

NNDC evaluated charged particle reaction data library (1975)

Energy Technology Data Exchange (ETDEWEB)

Pearlstein, S

1985-09-01

The US National Nuclear Data Center developed a `starter` library for charged particle induced nuclear reaction data in a trial ENDF/B format. It was issued in June 1974 and corrected in August 1975. It includes integral cross-section data for 306 nuclides between Z = 21 and 83 for the following reactions in the energy range from 0 to 20 MeV: (p,n); (p,2n); (p,3n); (d,n); (d,2n); (d,3n); (d,p); ({alpha},n); ({alpha},2n); ({alpha},3n); ({alpha},p) and ({alpha},np). The data were calculated following the nuclear systematics developed by J. Lange and H. Muenzel [KFK-767, May 19681]. The library serves to provide unmeasured cross sections and information that usually compares within an order of magnitude with actual data. It also serves as a convenient source for those requiring charged particle data in computerized form. The library contains 38,584 records. The following documentation is a reprint of a report by S. Pearlstein, BNL-19148, May 1974. (author) 6 refs, 12 figs

Nuclear-reaction studies via the observation of unbound outgoing systems

Energy Technology Data Exchange (ETDEWEB)

Bice, A.N.

1982-01-01

The mechanisms involved in the production of fast ..cap alpha..-particles in /sup 12/C induced reactions have been investigated for the /sup 12/C + /sup 208/Pb system at bombarding energies of E(/sup 12/C) = 132, 187 and 230 MeV. Absolute cross sections have been determined for the reactions /sup 208/Pb (/sup 12/C, /sup 8/Be (g.s.)), /sup 208/Pb(/sup 12/C, /sup 8/Be (2.94 MeV)) and /sup 208/Pb (/sup 12/C, /sup 12/C* ..-->.. ..cap alpha.. + /sup 8/Be) by double and triple coincidence measurements of the sequential decay ..cap alpha..-particles. Inclusive ..cap alpha..-particle production cross sections were also measured at E (/sup 12/C) = 187 MeV for comparison. It is found that the simple inelastic scattering process (/sup 12/C, /sup 12/C* ..-->.. ..cap alpha.. + /sup 8/Be) does not contribute significantly to the production of fast ..cap alpha..-particles but that the production of /sup 8/Be nuclei by projectile fragmentation is an important source of ..cap alpha..-particles. At the highest bombarding energy investigated (19 MeV/A) it appears that the /sup 12/C ..-->.. 3..cap alpha.. fragmentation reaction becomes more prominent at the expense of the /sup 12/C ..-->.. ..cap alpha.. + /sup 8/Be fragmentation channel. It is concluded that projectile spectroscopic properties and/or final state interactions are important in fragmentation reactions for these bombarding energies. In a kinematically complete experiment the direct and the sequential breakup channels of 10 MeV/A /sup 7/Li projectiles have been investigated with /sup 12/C and /sup 208/Pb targets. By appropriate arrangement of detector telescopes it was possible to define a kinematical window which allowed for the unambigious observation of both the direct (to the ..cap alpha..-t continuum) and the sequential components of a heavy-ion projectile breakup reaction. A semiclassical Monte Carlo type projectile breakup calculation was constructed which qualitatively reproduced the measured ..cap alpha

Two-stream cyclotron radiative instabilities due to the marginally mirror-trapped fraction for fustion alphas in tokamaks

Energy Technology Data Exchange (ETDEWEB)

Arunasalam, V.

1995-07-01

It is shown here that the marginally mirror-trapped fraction of the newly-born fusion alpha particles in the deuterium-tritium (DT) reaction dominated tokamak plasmas can induce a two-stream cyclotron radiative instability for the fast Alfven waves propagating near the harmonics of the alpha particle cyclotron frequency {omega}{sub c{alpha}}. This can explain both the experimentally observed time behavior and the spatially localized origin of the fusion product ion cyclotron emission (ICE) in TFTR at frequencies {omega} {approx} m{omega}{sub c{alpha}}.

Portable Neutron Generator with 9-Section Silicon $\\alpha $-Detector

CERN Document Server

Bystritsky, V M; Kadyshevskij, V G; Khasaev, T O; Kobzev, A P; Presnyakov, Yu K; Rogov,Yu N; Ryzhkov, V I; Sapozhnikov, M G; Sissakian, A N; Slepnev, V M; Zamyatin, N I

2006-01-01

The characteristics of the portable neutron generator with a built-in $\\alpha $-detector are presented. Based on the "tagged" neutron method (TNM) the generator ~is being used for identification of ~the hidden chemical compounds. One of the special features of such generators compared to generators traditionally used and produced in industry is that the generator is a source of monoenergetic "tagged" 14.1 MeV neutrons produced in the binary nuclear reaction $d+t \\to \\alpha $ (3.5 MeV) $+n$ (14.1~MeV). Unambiguous information about the time and direction of the neutron emitted from the target can be obtained by recording an $\\alpha $ particle by the multi-pixel $\\alpha $-detector placed inside the neutron tube. The study of the "tagged" neutron method (TNM) shows that the use of the ($\\alpha $--$\\gamma $) coincidence reduces the gamma background induced by scattered neutrons by a factor of more than 200, which allows the detection and identification of small quantities of explosives, drugs, and toxic agents. T...

The efficacy of intravitreal interferon alpha-2b for the treatment of experimental endotoxin-induced uveitis.

Science.gov (United States)

Afarid, Mehrdad; Lashkarizadeh, Hamid; Ashraf, Mohammad J; Nowroozzadeh, Mohammad Hossein; Shafiee, Sayed M

2016-05-01

To study the efficacy of intravitreal interferon alpha-2b for endotoxin-induced uveitis. A total of 36 rabbits were randomly allocated to one of the three groups: (1) received interferon plus balanced-salt solution; (2) received lipopolysaccharide (LPS) plus interferon; and (3) received LPS plus balanced-salt solution. Intraocular inflammation was evaluated by slit-lamp biomicroscopy (standardization of uveitis nomenclature grading), binocular indirect ophthalmoscopy (BIO) score, and histopathology. Group 2 showed significantly lower mean (±standard deviation) anterior chamber reaction than Group 3 (3.1 ± 0.9 vs. 3.8 ± 0.4) on day 1 postinjection, lower vitreous cells on days 1 through 7 (day 1: 3.1 ± 0.9 vs. 3.8 ± 0.4; day 3: 2.1 ± 1.6 vs. 3.8 ± 0.4; day 7: 1.9 ± 1.3 vs. 3.6 ± 0.7), and lower BIO score on days 1-7 (day 1: 3.3 ± 1.2 vs. 4.4 ± 0.7; day 3: 3.0 ± 1.4 vs. 4.3 ± 0.9; day 7: 2.4 ± 1.4 vs. 3.7 ± 1.2). The protein content of anterior and vitreous aspirates was lower in Group 2 than 3 (1618.5 ± 411.4 vs. 2567.3 ± 330.8 and 2157.0 ± 283.3 vs. 3204.6 ± 259.5, respectively). Intravitreal interferon alpha-2b was effective in controlling endotoxin-induced uveitis.

Alpha-induced reactions on selenium between 11 and 15 MeV

Science.gov (United States)

Fiebiger, Stefan; Slavkovská, Zuzana; Giesen, Ulrich; Göbel, Kathrin; Heftrich, Tanja; Heiske, Annett; Reifarth, René; Schmidt, Stefan; Sonnabend, Kerstin; Thomas, Benedikt; Weigand, Mario

2017-07-01

The production of 77,79,85,85m Kr and 77Br via the reaction Se(α ,x) was investigated between {E}α =11 and 15 MeV using the activation technique. The irradiation of natural selenium targets on aluminum backings was conducted at the Physikalisch-Technische Bundesanstalt (PTB) in Braunschweig, Germany. The spectroscopic analysis of the reaction products was performed using a high-purity germanium detector located at PTB and a low energy photon spectrometer detector at the Goethe University Frankfurt, Germany. Thick-target yields were determined. The corresponding energy-dependent production cross sections of 77,79,85,85m Kr and 77Br were calculated from the thick-target yields. Good agreement between experimental data and theoretical predictions using the TALYS-1.6 code was found.

HNF4alpha dysfunction as a molecular rational for cyclosporine induced hypertension.

Science.gov (United States)

Niehof, Monika; Borlak, Jürgen

2011-01-27

Induction of tolerance against grafted organs is achieved by the immunosuppressive agent cyclosporine, a prominent member of the calcineurin inhibitors. Unfortunately, its lifetime use is associated with hypertension and nephrotoxicity. Several mechanism for cyclosporine induced hypertension have been proposed, i.e. activation of the sympathetic nervous system, endothelin-mediated systemic vasoconstriction, impaired vasodilatation secondary to reduction in prostaglandin and nitric oxide, altered cytosolic calcium translocation, and activation of the renin-angiotensin system (RAS). In this regard the molecular basis for undue RAS activation and an increased signaling of the vasoactive oligopeptide angiotensin II (AngII) remain elusive. Notably, angiotensinogen (AGT) is the precursor of AngII and transcriptional regulation of AGT is controlled by the hepatic nuclear factor HNF4alpha. To better understand the molecular events associated with cyclosporine induced hypertension, we investigated the effect of cyclosporine on HNF4alpha expression and activity and searched for novel HNF4alpha target genes among members of the RAS cascade. Using bioinformatic algorithm and EMSA bandshift assays we identified angiotensin II receptor type 1 (AGTR1), angiotensin I converting enzyme (ACE), and angiotensin I converting enzyme 2 (ACE2) as genes targeted by HNF4alpha. Notably, cyclosporine represses HNF4alpha gene and protein expression and its DNA-binding activity at consensus sequences to AGT, AGTR1, ACE, and ACE2. Consequently, the gene expression of AGT, AGTR1, and ACE2 was significantly reduced as evidenced by quantitative real-time RT-PCR. While RAS is composed of a sophisticated interplay between multiple factors we propose a decrease of ACE2 to enforce AngII signaling via AGTR1 to ultimately result in vasoconstriction and hypertension. Taken collectively we demonstrate cyclosporine to repress HNF4alpha activity through calcineurin inhibitor mediated inhibition of nuclear

HNF4alpha dysfunction as a molecular rational for cyclosporine induced hypertension.

Directory of Open Access Journals (Sweden)

Monika Niehof

Full Text Available Induction of tolerance against grafted organs is achieved by the immunosuppressive agent cyclosporine, a prominent member of the calcineurin inhibitors. Unfortunately, its lifetime use is associated with hypertension and nephrotoxicity. Several mechanism for cyclosporine induced hypertension have been proposed, i.e. activation of the sympathetic nervous system, endothelin-mediated systemic vasoconstriction, impaired vasodilatation secondary to reduction in prostaglandin and nitric oxide, altered cytosolic calcium translocation, and activation of the renin-angiotensin system (RAS. In this regard the molecular basis for undue RAS activation and an increased signaling of the vasoactive oligopeptide angiotensin II (AngII remain elusive. Notably, angiotensinogen (AGT is the precursor of AngII and transcriptional regulation of AGT is controlled by the hepatic nuclear factor HNF4alpha. To better understand the molecular events associated with cyclosporine induced hypertension, we investigated the effect of cyclosporine on HNF4alpha expression and activity and searched for novel HNF4alpha target genes among members of the RAS cascade. Using bioinformatic algorithm and EMSA bandshift assays we identified angiotensin II receptor type 1 (AGTR1, angiotensin I converting enzyme (ACE, and angiotensin I converting enzyme 2 (ACE2 as genes targeted by HNF4alpha. Notably, cyclosporine represses HNF4alpha gene and protein expression and its DNA-binding activity at consensus sequences to AGT, AGTR1, ACE, and ACE2. Consequently, the gene expression of AGT, AGTR1, and ACE2 was significantly reduced as evidenced by quantitative real-time RT-PCR. While RAS is composed of a sophisticated interplay between multiple factors we propose a decrease of ACE2 to enforce AngII signaling via AGTR1 to ultimately result in vasoconstriction and hypertension. Taken collectively we demonstrate cyclosporine to repress HNF4alpha activity through calcineurin inhibitor mediated inhibition

A RNA antagonist of hypoxia-inducible factor-1alpha, EZN-2968, inhibits tumor cell growth

DEFF Research Database (Denmark)

Greenberger, Lee M; Horak, Ivan D; Filpula, David

2008-01-01

Hypoxia-inducible factor-1 (HIF-1) is a transcription factor that plays a critical role in angiogenesis, survival, metastasis, drug resistance, and glucose metabolism. Elevated expression of the alpha-subunit of HIF-1 (HIF-1alpha), which occurs in response to hypoxia or activation of growth facto...

Prolactin, TNF alpha and nitric oxide expression in nitroso-N-methylurea-induced-mammary tumours

Directory of Open Access Journals (Sweden)

Vegh Irene

2007-11-01

Full Text Available Abstract Background The N-Nitrosomethylurea breast cancer model induced in rats is used for the study of carcinogenesis in mammary cancer, prostate, pancreas, etc. This model is very similar to human neoplastic disease. Methods The present experimental study was designed to assess whether metoclopramide administration has any effect on development of MNU-induced tumours, and evaluate the treatment of goserelin acetate on PRL, TNF alpha and NO expression. NMU was administered to female Wistar rats on 2 occasions (5 mg/100 g body w/rat. PRL and TNF alpha were performed by immune-assay. Nitric Oxide by semi automated-assay and ploidy analyses by flow cytometry. Results The administration of metoclopramide made the induction time shorter and increased the incidence and average of tumours per rat. Tumours development was inhibited by a goserelin chronic administration. The ploidy of adenocarcinoma was polyploid-aneuploid type (average S = 60%. It was higher basal PRL plasma levels in rats with NMU induced tumours than in basal controls without tumour (p Conclusion The increase of blood PRL levels in NMU-induced rats may be an indicator of a poor prognosis of mammary cancer evolution. The metoclopramide administration accelerates tumour growth. However goserelin administration achieves regression in tumour development associated to inhibition PRL, TNF alpha and NO expression.

Trojan Horse Method for neutrons-induced reaction studies

Science.gov (United States)

Gulino, M.; Asfin Collaboration

2017-09-01

Neutron-induced reactions play an important role in nuclear astrophysics in several scenario, such as primordial Big Bang Nucleosynthesis, Inhomogeneous Big Bang Nucleosynthesis, heavy-element production during the weak component of the s-process, explosive stellar nucleosynthesis. To overcome the experimental problems arising from the production of a neutron beam, the possibility to use the Trojan Horse Method to study neutron-induced reactions has been investigated. The application is of particular interest for reactions involving radioactive nuclei having short lifetime.

Activation cross-section data for -particle-induced nuclear reactions ...

Indian Academy of Sciences (India)

B M ALI

2018-02-20

particle-induced nuclear reactions on natural vanadium up to 20 MeV. It should be mentioned that this study represents a part of (a supplement) systematical study of charged particles-induced nuclear reactions. Earlier studies were.

Fluid transport in reaction induced fractures

Science.gov (United States)

Ulven, Ole Ivar; Sun, WaiChing; Malthe-Sørenssen, Anders

2015-04-01

The process of fracture formation due to a volume increasing chemical reaction has been studied in a variety of different settings, e.g. weathering of dolerites by Røyne et al. te{royne}, serpentinization and carbonation of peridotite by Rudge et al. te{rudge} and replacement reactions in silica-poor igneous rocks by Jamtveit et al. te{jamtveit}. It is generally assumed that fracture formation will increase the net permeability of the rock, and thus increase the reactant transport rate and subsequently the total rate of material conversion, as summarised by Kelemen et al. te{kelemen}. Ulven et al. te{ulven_1} have shown that for fluid-mediated processes the ratio between chemical reaction rate and fluid transport rate in bulk rock controls the fracture pattern formed, and Ulven et al. te{ulven_2} have shown that instantaneous fluid transport in fractures lead to a significant increase in the total rate of the volume expanding process. However, instantaneous fluid transport in fractures is clearly an overestimate, and achievable fluid transport rates in fractures have apparently not been studied in any detail. Fractures cutting through an entire domain might experience relatively fast advective reactant transport, whereas dead-end fractures will be limited to diffusion of reactants in the fluid, internal fluid mixing in the fracture or capillary flow into newly formed fractures. Understanding the feedback process between fracture formation and permeability changes is essential in assessing industrial scale CO2 sequestration in ultramafic rock, but little is seemingly known about how large the permeability change will be in reaction-induced fracturing. In this work, we study the feedback between fracture formation during volume expansion and fluid transport in different fracture settings. We combine a discrete element model (DEM) describing a volume expanding process and the related fracture formation with different models that describe the fluid transport in the

Astrophysical rate of O-15(alpha,gamma)Ne-19 via the (p, t) reaction in inverse kinematics

NARCIS (Netherlands)

Davids, B; van den Berg, AM; Dendooven, P; Fleurot, F; Hunyadi, M; de Huu, MA; Siemssen, RH; Wilschut, HW; Wortche, HJ; Hernanz, M; Jose, J; Rehm, KE; Wuosmaa, AH; Segel, RE

A recoil coincidence technique has been applied to measure the alpha-decay branching ratios of near-threshold states in Ne-19. Populating these states using the (p,t) reaction in inverse kinematics, we detected the recoils and their decay products with 100% geometric efficiency using a magnetic

Precompound decay models for medium energy nuclear reactions

International Nuclear Information System (INIS)

Blann, M.

1989-11-01

The formulations used for precompound decay models are presented and explained in terms of the physics of the intranuclear cascade model. Several features of spectra of medium energy (10--1000 MeV) reactions are summarized. Results of precompound plus evaporation calculations from the code ALICE are compared with a wide body of proton, alpha, and heavy ion induced reaction data to illustrate both the power and deficiencies of predicting yield of these reactions in the medium energy regime. 23 refs., 13 figs

Theoretical and experimental studies of the efficiency of a solid-state track detector utilizing (neutron, alpha) reactions

International Nuclear Information System (INIS)

Palfalvi, J.

1983-04-01

The neutron sensitivity of Kodak-Pathe LR 115 II type cellulose nitrate track detectors with different (n,α) radiators was investigated by calculations and measurements. The α counting efficiency using an optical microscope is 95% for α particles with maximum energy of 2 MeV. When using an image analyzer the etched through-tracks (holes) with diameters greater than 2 μm are counted. The efficiency then depends only on the original and removed layer thickness but not on the etching temperature within the range of 40 to 60 deg C and the 2.5 to 6 N normality of the NaOH etchant. Efficiency varies from about 3 to 20% for alphas from the 6 Li/n, +a/T reaction if the removed layer lies in the range of 7 to 10 μm, and varies from 2 to 10% for 10 B/n, α/ 7 Li reaction alphas when the layer re--moval is 8 to 10 μm. (author)

Effects of a new 3-alpha reaction on the s-process in massive stars

International Nuclear Information System (INIS)

Kikuch, Yukihiro; Ono, Masaomi; Matsuo, Yasuhide; Hashimoto, Masa-aki; Fujimoto, Shin-ichiro

2012-01-01

Effect of a new 3-alpha reaction rate on the s-process during the evolution of a massive star of 25 solar mass is investigated for the first time, because the s-process in massive stars have been believed to be established with only minor change. We find that the s-process with use of the new rate during the core helium burning is very inefficient compared to the case with the previous 3-alpha rate. However, the difference of the overproduction is found to be largely compensated by the subsequent carbon burning. Since the s-process in massive stars has been attributed so far to the neutron irradiation during core helium burning, our finding reveals for the first time the importance of the carbon burning for the s-process during the evolution of massive stars.

Contribution to the study of excited levels of {sup 7}Be obtained from the reaction {sup 6}Li (p, {alpha}); Contribution a l'etude des niveaux excites du {sup 7}Be obtenus par la reaction {sup 6}Li (p, {alpha})

Energy Technology Data Exchange (ETDEWEB)

Beaumevieille, H. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1964-05-01

The interpretation of the results of the reaction {sup 6}Li (p, {alpha}) in the energy range 100 keV to 3 MeV has been done with the next levels of {sup 7}Be : 3/2- (5,9 MeV), 3/2+ (6,2 MeV), 5/2- (7,18 MeV) and a level the characteristics of which may be 1/2+ or {sup 4}P (9,5 MeV). (author) [French] L'interpretation des resultats de la reaction {sup 6}Li (p, {alpha}) dans la gamme d'energie 100 keV a 3 MeV a ete faite avec les niveaux suivants du {sup 7}Be : 3/2- (5,9 MeV), 3/2 + (6,2 MeV), 5/2- (7,18 MeV) et un niveau dont les caracteristiques doivent etre 1/2+ ou {sup 4}P (9,5 MeV). (auteur)

Contribution to the study of excited levels of {sup 7}Be obtained from the reaction {sup 6}Li (p, {alpha}); Contribution a l'etude des niveaux excites du {sup 7}Be obtenus par la reaction {sup 6}Li (p, {alpha})

Energy Technology Data Exchange (ETDEWEB)

Beaumevieille, H [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1964-05-01

The interpretation of the results of the reaction {sup 6}Li (p, {alpha}) in the energy range 100 keV to 3 MeV has been done with the next levels of {sup 7}Be : 3/2- (5,9 MeV), 3/2+ (6,2 MeV), 5/2- (7,18 MeV) and a level the characteristics of which may be 1/2+ or {sup 4}P (9,5 MeV). (author) [French] L'interpretation des resultats de la reaction {sup 6}Li (p, {alpha}) dans la gamme d'energie 100 keV a 3 MeV a ete faite avec les niveaux suivants du {sup 7}Be : 3/2- (5,9 MeV), 3/2 + (6,2 MeV), 5/2- (7,18 MeV) et un niveau dont les caracteristiques doivent etre 1/2+ ou {sup 4}P (9,5 MeV). (auteur)

Bibliographic index to photonuclear reaction data

International Nuclear Information System (INIS)

Asami, Tetsuo; Nakagawa, Tsuneo.

1993-10-01

This report contains the bibliographic index data on photonuclear reactions and on their inverse ones, in the format similar to CINDA for neutron nuclear data. As photonuclear reactions the electron-induced reaction data are also included. As the inverse reactions considered are those induced by neutron, proton, deuteron, triton, helion and alpha particles. The index covers major journals on nuclear data published in 1995 to 1992, for all nuclides through hydrogen (H) to einsteinium (Es). The bibliographic index contains information on target nucleus, incident beam, type of reaction and quantity, energy range of incident beam, laboratory, type of work, reference citations, first author's name, and short comment. The index also contains the indication for information on cross-section data. All the index data are listed in the order of target element, target, mass and incident particle, and in the chronological order of reference data. Also a brief description is given on the data format, the abbreviations used and the journals surveyed. (author)

Unimolecular and collisionally induced ion reactions

International Nuclear Information System (INIS)

Beynon, J.H.; Boyd, R.K.

1978-01-01

The subject is reviewed under the following headings: introduction (mass spectroscopy and the study of fragmentation reactions of gaseous positive ions); techniques and methods (ion sources, detection systems, analysis of ions, data reduction); collision-induced reactions of ions and unimolecular fragmentations of metastable ions; applications (ion structure, energetic measurements, analytical applications, other applications). 305 references. (U.K.)

Vibration induced hearing loss in guinea pig cochlea: expression of TNF-alpha and VEGF.

Science.gov (United States)

Zou, Jing; Pyykkö, Ilmari; Sutinen, Päivi; Toppila, Esko

2005-04-01

Transcranial vibration was applied for seven animals at a frequency of 250 Hz for 15 min, and five animals were used as normal controls to investigate cellular and molecular mechanism linked to vibration-induced hearing loss in animal model. Compound action potential (CAP) thresholds were measured by round window niche electrode. The expression of tumour necrosis factor alpha (TNF-alpha) and its receptors (TNF R1, TNF R2), vascular endothelium growth factor (VEGF) and its receptors (VEGF R1, VEGF R2) were analysed by immunohistochemistry. Transcranial vibration caused expression of TNF-alpha, TNF R1 and TNF R2 in the cochlea and the expression of TNF R2 was stronger than that of TNF R1. Vibration also induced VEGF and VEGF R2 expression in the cochlea. The average immediate hearing loss was 62 dB and after three days still 48 dB. It is concluded that transcranial vibration as during temporal bone drilling produces cochlear shear stress that is connected with up-regulation of TNF-alpha and its receptors. Also VEGF and VEGF R2 are up-regulated. These responses may be linked to both the damage and repair process of the cochlea.

Prediction of lung cells oncogenic transformation for induced radon progeny alpha particles using sugarscape cellular automata.

Science.gov (United States)

Baradaran, Samaneh; Maleknasr, Niaz; Setayeshi, Saeed; Akbari, Mohammad Esmaeil

2014-01-01

Alpha particle irradiation from radon progeny is one of the major natural sources of effective dose in the public population. Oncogenic transformation is a biological effectiveness of radon progeny alpha particle hits. The biological effects which has caused by exposure to radon, were the main result of a complex series of physical, chemical, biological and physiological interactions. The cellular and molecular mechanisms for radon-induced carcinogenesis have not been clear yet. Various biological models, including cultured cells and animals, have been found useful for studying the carcinogenesis effects of radon progeny alpha particles. In this paper, sugars cape cellular automata have been presented for computational study of complex biological effect of radon progeny alpha particles in lung bronchial airways. The model has included mechanism of DNA damage, which has been induced alpha particles hits, and then formation of transformation in the lung cells. Biomarkers were an objective measure or evaluation of normal or abnormal biological processes. In the model, the metabolism rate of infected cell has been induced alpha particles traversals, as a biomarker, has been followed to reach oncogenic transformation. The model results have successfully validated in comparison with "in vitro oncogenic transformation data" for C3H 10T1/2 cells. This model has provided an opportunity to study the cellular and molecular changes, at the various stages in radiation carcinogenesis, involving human cells. It has become well known that simulation could be used to investigate complex biomedical systems, in situations where traditional methodologies were difficult or too costly to employ.

Alpha-fetoprotein is a predictor of outcome in acetaminophen-induced liver injury

DEFF Research Database (Denmark)

Schmidt, Lars E; Dalhoff, Kim

2005-01-01

An increase in alpha-fetoprotein (AFP) following hepatic necrosis is considered indicative of hepatic regeneration. This study evaluated the prognostic value of serial AFP measurements in patients with severe acetaminophen-induced liver injury. Prospectively, serial measurements of AFP were...

Xanthophylls and alpha-tocopherol decrease UVB-induced lipid peroxidation and stress signaling in human lens epithelial cells.

Science.gov (United States)

Chitchumroonchokchai, Chureeporn; Bomser, Joshua A; Glamm, Jayme E; Failla, Mark L

2004-12-01

Epidemiological studies suggest that consumption of vegetables rich in the xanthophylls lutein (LUT) and zeaxanthin (ZEA) reduces the risk for developing age-related cataract, a leading cause of vision loss. Although LUT and ZEA are the only dietary carotenoids present in the lens, direct evidence for their photoprotective effect in this organ is not available. The present study examined the effects of xanthophylls and alpha-tocopherol (alpha-TC) on lipid peroxidation and the mitogen-activated stress signaling pathways in human lens epithelial (HLE) cells following ultraviolet B light (UVB) irradiation. When presented with LUT, ZEA, astaxanthin (AST), and alpha-TC as methyl-beta-cyclodextrin complexes, HLE cells accumulated the lipophiles in a concentration- and time-dependent manner with uptake of LUT exceeding that of ZEA and AST. Pretreatment of cultures with either 2 micromol/L xanthophyll or 10 micromol/L alpha-TC for 4 h before exposure to 300 J/m(2) UVB radiation decreased lipid peroxidation by 47-57% compared with UVB-treated control HLE cells. Pretreatment with the xanthophylls and alpha-TC also inhibited UVB-induced activation of c-JUN NH(2)-terminal kinase (JNK) and p38 by 50-60 and 25-32%, respectively. There was substantial inhibition of UVB-induced JNK and p38 activation for cells containing xanthophylls/mg, respectively, whereas >2.3 nmol alpha-TC/mg protein was required to significantly decrease UVB-induced stress signaling. These data suggest that xanthophylls are more potent than alpha-TC for protecting human lens epithelial cells against UVB insult.

Dependence of ICF reaction dynamics on target structure

International Nuclear Information System (INIS)

Kumar, Kamal; Dutt, Sunil; GulI, Muntazir; Ahmad, Tauseef; Rizvi, I.A.; Ali, Sabir; Agarwal, Avinash; Kumar, R.; Chaubey, A.K.

2016-01-01

The projectile structure is also found responsible for the ICF reaction processes. It is found that projectile having bigger alpha cluster is more unstable towards break up. In this context, a comparative study of 12 C and 16 O ion-beams induced reactions with different targets has been done. The deduced ICF contributions for different systems have been plotted against the target charge of different targets. It is observed that target properties may also be responsible for the interplay between CF and ICF reaction dynamics

The efficacy of intravitreal interferon alpha-2b for the treatment of experimental endotoxin-induced uveitis

Directory of Open Access Journals (Sweden)

Mehrdad Afarid

2016-01-01

Full Text Available Purpose: To study the efficacy of intravitreal interferon alpha-2b for endotoxin-induced uveitis. Materials and Methods: A total of 36 rabbits were randomly allocated to one of the three groups: (1 received interferon plus balanced-salt solution; (2 received lipopolysaccharide (LPS plus interferon; and (3 received LPS plus balanced-salt solution. Intraocular inflammation was evaluated by slit-lamp biomicroscopy (standardization of uveitis nomenclature grading, binocular indirect ophthalmoscopy (BIO score, and histopathology. Results: Group 2 showed significantly lower mean (±standard deviation anterior chamber reaction than Group 3 (3.1 ± 0.9 vs. 3.8 ± 0.4 on day 1 postinjection, lower vitreous cells on days 1 through 7 (day 1: 3.1 ± 0.9 vs. 3.8 ± 0.4; day 3: 2.1 ± 1.6 vs. 3.8 ± 0.4; day 7: 1.9 ± 1.3 vs. 3.6 ± 0.7, and lower BIO score on days 1-7 (day 1: 3.3 ± 1.2 vs. 4.4 ± 0.7; day 3: 3.0 ± 1.4 vs. 4.3 ± 0.9; day 7: 2.4 ± 1.4 vs. 3.7 ± 1.2. The protein content of anterior and vitreous aspirates was lower in Group 2 than 3 (1618.5 ± 411.4 vs. 2567.3 ± 330.8 and 2157.0 ± 283.3 vs. 3204.6 ± 259.5, respectively. Conclusion: Intravitreal interferon alpha-2b was effective in controlling endotoxin-induced uveitis.

Alpha band cortico-muscular coherence occurs in healthy individuals during mechanically-induced tremor.

Directory of Open Access Journals (Sweden)

Francesco Budini

Full Text Available The present work aimed at investigating the effects of mechanically amplified tremor on cortico-muscular coherence (CMC in the alpha band. The study of CMC in this specific band is of particular interest because this coherence is usually absent in healthy individuals and it is an aberrant feature in patients affected by pathological tremors; understanding its mechanisms is therefore important. Thirteen healthy volunteers (23±4 years performed elbow flexor sustained contractions both against a spring load and in isometric conditions at 20% of maximal voluntary isometric contraction (MVC. Spring stiffness was selected to induce instability in the stretch reflex servo loop. 64 EEG channels, surface EMG from the biceps brachii muscle and force were simultaneously recorded. Contractions against the spring resulted in greater fluctuations of the force signal and EMG amplitude compared to isometric conditions (p<.05. During isometric contractions CMC was systematically found in the beta band and sporadically observed in the alpha band. However, during the contractions against the spring load, CMC in the alpha band was observed in 12 out of 13 volunteers. Partial directed coherence (PDC revealed an increased information flow in the EMG to EEG direction in the alpha band (p<.05. Therefore, coherence in the alpha band between the sensory-motor cortex and the biceps brachii muscle can be systematically induced in healthy individuals by mechanically amplifying tremor. The increased information flow in the EMG to EEG direction may reflect enhanced afferent activity from the muscle spindles. These results may contribute to the understanding of the presence of alpha band CMC in tremor related pathologies by suggesting that the origin of this phenomenon may not only be at cortical level but may also be affected by spinal circuit loops.

Alpha7 nicotinic receptor mediated protection against ethanol-induced cytotoxicity in PC12 cells.

Science.gov (United States)

Li, Y; King, M A; Grimes, J; Smith, N; de Fiebre, C M; Meyer, E M

1999-01-16

Ethanol caused a concentration-dependent loss of PC12 cells over a 24 h interval, accompanied by an increase in intracellular calcium. The specific alpha7 nicotinic receptor partial agonist DMXB attenuated both of these ethanol-induced actions at a concentration (3 microM) found previously to protect against apoptotic and necrotic cell loss. The alpha7 nicotinic receptor antagonist methylylaconitine blocked the neuroprotective action of DMXB when applied with but not 30 min after the agonist. These results indicate that activation of alpha7 nicotinic receptors may be therapeutically useful in preventing ethanol-neurotoxicity. Copyright 1999 Elsevier Science B.V.

The tumor necrosis factor-alpha-induced protein 8 family in immune homeostasis and inflammatory cancer diseases.

Science.gov (United States)

Luan, Y Y; Yao, Y M; Sheng, Z Y

2013-01-01

Within the immune system homeostasis is maintained by a myriad of mechanisms that include the regulation of immune cell activation and programmed cell death. The breakdown of immune homeostasis may lead to fatal inflammatory diseases. We set out to identify genes of tumor necrosis factor-alpha-induced protein 8 (TNFAIP8) family that has a functional role in the process of immune homeostasis. Tumor necrosis factor-alpha-induced protein 8 (TNFAIP8), which functions as an oncogenic molecule, is also associated with enhanced cell survival and inhibition of apoptosis. Tumor necrosis factor-alpha-induced protein 8-like 2 (TIPE2) governs immune homeostasis in both the innate and adaptive immune system and prevents hyper-responsiveness by negatively regulating signaling via T cell receptors and Toll-like receptors (TLRs). There also exist two highly homologous but uncharacterized proteins, TIPE1 and TIPE3. This review is an attempt to provide a summary of TNFAIP8 family associated with immune homeostasis and inflammatory cancer diseases.

K-shell X-ray production cross sections of Ni induced by protons, alpha-particles, and He{sup +}

Energy Technology Data Exchange (ETDEWEB)

Bertol, A.P.L. [Programa de Pós-graduação em Física, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Hinrichs, R. [Programa de Pós-graduação em Física, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Instituto de Geociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Vasconcellos, M.A.Z., E-mail: marcos@if.ufrgs.br [Programa de Pós-graduação em Física, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Instituto de Física, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil)

2015-11-15

The proton, alpha-particle, and He{sup +} induced X-ray emissions of Ni were measured on mono-elemental thin films in order to obtain the K-shell X-ray production cross section in the energy range of 0.7–2.0 MeV for protons, 4.0–6.5 MeV for alpha-particles, and 3.0–4.0 MeV for He{sup +}. The proton-induced X-ray production cross section for Ni agreed well with the theoretical values, endorsing the quality of the measurements. The X-ray production cross section induced with alpha-particles is in good agreement with ECPSSR theory in the complete range of energies, while for He{sup +} that quantity is systematically below. K{sub β}/K{sub α} ratios were evaluated and compared with experimental and theoretical values.

Benfotiamine alleviates diabetes-induced cerebral oxidative damage independent of advanced glycation end-product, tissue factor and TNF-alpha.

Science.gov (United States)

Wu, Shan; Ren, Jun

2006-02-13

Diabetes mellitus leads to thiamine deficiency and multiple organ damage including diabetic neuropathy. This study was designed to examine the effect of benfotiamine, a lipophilic derivative of thiamine, on streptozotocin (STZ)-induced cerebral oxidative stress. Adult male FVB mice were made diabetic with a single injection of STZ (200 mg/kg, i.p.). Fourteen days later, control and diabetic (fasting blood glucose >13.9 mM) mice received benfotiamine (100 mg/kg/day, i.p.) for 14 days. Oxidative stress and protein damage were evaluated by glutathione/glutathione disulfide (GSH/GSSG) assay and protein carbonyl formation, respectively. Pro-oxidative or pro-inflammatory factors including advanced glycation end-product (AGE), tissue factor and tumor necrosis factor-alpha (TNF-alpha) were evaluated by immunoblot analysis. Four weeks STZ treatment led to hyperglycemia, enhanced cerebral oxidative stress (reduced GSH/GSSG ratio), elevated TNF-alpha and AGE levels without changes in protein carbonyl or tissue factor. Benfotiamine alleviated diabetes-induced cerebral oxidative stress without affecting levels of AGE, protein carbonyl, tissue factor and TNF-alpha. Collectively, our results indicated benfotiamine may antagonize diabetes-induced cerebral oxidative stress through a mechanism unrelated to AGE, tissue factor and TNF-alpha.

IgE-mediated basophil tumour necrosis factor alpha induces matrix metalloproteinase-9 from monocytes

DEFF Research Database (Denmark)

Falkencrone, Sidsel; Poulsen, Lars K.; Bindslev-Jensen, Carsten

2013-01-01

IgE-mediated activation of mast cells has been reported to induce the release of tumour necrosis alpha (TNF-α), which may display autocrine effects on these cells by inducing the generation of the tissue remodelling protease matrix metalloproteinase-9 (MMP-9). While mast cells and basophils have...

Evidence for a Field-induced Quantum Spin Liquid in $\\alpha$-RuCl$_3$

OpenAIRE

Baek, S. -H.; Do, S. -H.; Choi, K. -Y.; Kwon, Y. S.; Wolter, A. U. B.; Nishimoto, S.; Brink, Jeroen van den; Büchner, B.

2017-01-01

We report a $^{35}$Cl nuclear magnetic resonance study in the honeycomb lattice, $\\alpha$-RuCl$_3$, a material that has been suggested to potentially realize a Kitaev quantum spin liquid (QSL) ground state. Our results provide direct evidence that $\\alpha$-RuCl$_3$ exhibits a magnetic field-induced QSL. For fields larger than $\\sim 10$ T a spin-gap opens up while resonance lines remain sharp, evidencing that spins are quantum disordered and locally fluctuating. The spin gap increases linearly...

Study of the p+{sup 12}C reaction at energies up to 30 MeV

Energy Technology Data Exchange (ETDEWEB)

Harada, Masahide; Yamamoto, A.; Yoshioka, S. [Kyushu Univ., Fukuoka (Japan)] [and others

1998-03-01

Double differential cross sections of charged-particles emitted in the p+{sup 12}C reaction were measured in the energy region from 14 to 26 MeV. The observed continuous components of emitted protons and {alpha}-particles were analyzed by assuming sequential decay of intermediate reaction products and/or simultaneous breakup process. It was found that the three body simultaneous decay, p+{alpha}+{sup 8}Be, and the sequential decay via p+{sup 12}C{sup *}{sub 3-} and {alpha}+{sup 9}B{sub g.s.} are most important in the proton-induced breakup of {sup 12}C for energies up to 30 MeV. (author)

Protection against dexamethasone-induced muscle atrophy is related to modulation by testosterone of FOXO1 and PGC-1{alpha}

Energy Technology Data Exchange (ETDEWEB)

Qin, Weiping, E-mail: weiping.qin@mssm.edu [Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, Bronx, NY (United States); Department of Medicine, Mount Sinai School of Medicine, NY (United States); Pan, Jiangping; Wu, Yong [Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, Bronx, NY (United States); Bauman, William A. [Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, Bronx, NY (United States); Department of Medicine, Mount Sinai School of Medicine, NY (United States); Department of Rehabilitation Medicine, Mount Sinai School of Medicine, NY (United States); Cardozo, Christopher, E-mail: Chris.Cardozo@mssm.edu [Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, Bronx, NY (United States); Department of Medicine, Mount Sinai School of Medicine, NY (United States); Department of Rehabilitation Medicine, Mount Sinai School of Medicine, NY (United States)

2010-12-17

Research highlights: {yields} In rat gastrocnemius muscle, dexamethasone reduced PGC-1{alpha} cellular and nuclear levels without altering mRNA levels for this factor. {yields} Dexamethasone reduced phosphorylating of p38 MAPK, which stabilizes PGC-1{alpha} and promotes its nuclear entry. {yields} Co-administration of testosterone with dexamethasone increased cellular and nuclear levels of PGC-1{alpha} protein without changing its mRNA levels. {yields} Co-administration of testosterone restored p38 MAPK levels to those of controls. -- Abstract: Glucocorticoid-induced muscle atrophy results from muscle protein catabolism and reduced protein synthesis, associated with increased expression of two muscle-specific ubiquitin ligases (MAFbx and MuRF1), and of two inhibitors of protein synthesis, REDD1 and 4EBP1. MAFbx, MuRF1, REDD1 and 4EBP1 are up-regulated by the transcription factors FOXO1 and FOXO3A. The transcriptional co-activator PGC-1{alpha} has been shown to attenuate many forms of muscle atrophy and to repress FOXO3A-mediated transcription of atrophy-specific genes. Dexamethasone-induced muscle atrophy can be prevented by testosterone, which blocks up-regulation by dexamethasone of FOXO1. Here, an animal model of dexamethasone-induced muscle atrophy was used to further characterize effects of testosterone to abrogate adverse actions of dexamethasone on FOXO1 levels and nuclear localization, and to determine how these agents affect PGC-1{alpha}, and its upstream activators, p38 MAPK and AMPK. In rat gastrocnemius muscle, testosterone blunted the dexamethasone-mediated increase in levels of FOXO1 mRNA, and FOXO1 total and nuclear protein. Dexamethasone reduced total and nuclear PGC-1{alpha} protein levels in the gastrocnemius; co-administration of testosterone with dexamethasone increased total and nuclear PGC-1{alpha} levels above those present in untreated controls. Testosterone blocked dexamethasone-induced decreases in activity of p38 MAPK in the gastrocnemius

[Alpha interferon induced hyperthyroidism: a case report and review of the literature].

Science.gov (United States)

Maiga, I; Valdes-Socin, H; Thiry, A; Delwaide, J; Sidibe, A T; Beckers, A

2015-01-01

Treatment with alpha interferon in hepatitis C triggers a thyroid autoimmunity in a variable percentage of cases (2-8%). This complication raises some questions about its screening, the possibility to continue anti-viral therapy and thyroid treatment. Alpha interferon has an immunomodulatory effect on the thyroid, but also an inhibitory effect on thyroid hormone synthesis. This explains the occurrence of cases of thyroid dysfunction, which often remain undetected because of their latency. Factors predicting thyroid dysfunction with interferon use are: female sex, history of thyroid disease and previous autoimmunity. Several clinical aspects are encountered including hypothyroidism (the most frequent depending on the series) and hyperthyroidism related to Graves' disease. For their detection, a cooperation between general practionners, gastroenterologists and endocrinologists is mandatory thyroid function tests are requested before, during and after treatment,with alpha interferon. Therapeutic aspects of thyroid disorders range from simple monitoring to symptomatic treatment, such as thyroxine prescription in the presence of hypothyroidism. Antithyroid drugs radioactive iodine or thyroid surgery are used in cases of severe or persistent Graves' disease induced by alpha interferon.

Kiss-induced severe anaphylactic reactions

Directory of Open Access Journals (Sweden)

Atanasković-Marković Marina

2010-01-01

Full Text Available Introduction. Ingestion is the principal route for food allergens to trigger allergic reaction in atopic persons. However, in some highly sensitive patients severe symptoms may develop upon skin contact and by inhalation. The clinical spectrum ranges from mild facial urticaria and angioedema to life-threatening anaphylactic reactions. Outline of Cases. We describe cases of severe anaphylactic reactions by skin contact, induced by kissing in five children with prior history of severe anaphylaxis caused by food ingestion. These cases were found to have the medical history of IgE mediated food allergy, a very high total and specific serum IgE level and very strong family history of allergy. Conclusion. The presence of tiny particles of food on the kisser's lips was sufficient to trigger an anaphylactic reaction in sensitized children with prior history of severe allergic reaction caused by ingestion of food. Allergic reaction provoked with food allergens by skin contact can be a risk factor for generalized reactions. Therefore, extreme care has to be taken in avoiding kissing allergic children after eating foods to which they are highly allergic. Considering that kissing can be a cause of severe danger for the food allergic patient, such persons should inform their partners about the risk factor for causing their food hypersensitivity.

Effect of hypoxia-inducible factor 1-alpha (HIF-1α) on proliferation ...

African Journals Online (AJOL)

Jane

2011-07-25

Jul 25, 2011 ... Full Length Research Paper. Effect of hypoxia-inducible factor 1-alpha ... 1Department of Neurosurgery, Ruijin Hospital, Shanghai JiaoTong University School of Medicine, Shanghai 200025,. China. 2Department of Neurosurgery, Chaoyang Hospital, Huainan, Anhui, China. 3Department of Neurosurgery ...

alpha(7) Nicotinic acetylcholine receptor activation prevents behavioral and molecular changes induced by repeated phencyclidine treatment

DEFF Research Database (Denmark)

Thomsen, Morten Skøtt; Christensen, Ditte Z; Hansen, Henrik H

2009-01-01

in a modified Y-maze test. Polymorphisms in the alpha(7) nicotinic acetylcholine receptor (nAChR) gene have been linked to schizophrenia. Here we demonstrate that acute administration of the selective alpha(7) nAChR partial agonist SSR180711 dose-dependently reversed the behavioral impairment induced by PCP...

Effects of dietary [alpha]-tocopherol and [beta]-carotene on lipid peroxidation induced by methyl mercuric chloride in mice

Energy Technology Data Exchange (ETDEWEB)

Raun Andersen, H; Andersen, O [Department of Environmental Medicine, University of Odense, Odense (Denmark)

1993-01-01

Exposure of male CBA mice to methyl mercuric chloride, CH[sub 3]HgCl, (10-40 mg/l in drinking water) for 2 weeks resulted in dose-related Hg deposition and enhanced lipid peroxidation in liver, kidney and brain. Mice were fed well-defined semisynthetic diets containing different levels of [alpha]-tocopherol (10, 100 or 1000 mg/kg) or [beta]-carotene (1000, 10,000 or 100,000 IU/kg) for four weeks, two groups on each diet. The concentration of [alpha]-tocopherol and [beta]-carotene used corresponded to deficient, normal and high levels. During the last two weeks, one group on each diet was given 40 mg CH[sub 3]HgCl/l of drinking water. High dietary [alpha]-tocopherol protected against CH[sub 3]HgCl induced hepatic lipid peroxidation, whereas the [alpha]-tocopherol deficient diet further enhanced CH[sub 3]HgCl induced hepatic lipid peroxidation. Similar, though statistically non-significant effects occurred in the kidneys, [alpha]-tocopherol did not protect against CH[sub 3]HgCl induced lipid peroxidation in the brain. Excess dietary [beta]-carotene further enhanced CH[sub 3]HgCl induced lipid peroxidation in liver, kidney and brain. CH[sub 3]HgCl significantly decreased the activity of total glutathione peroxidase (T-GSH-Px) and Se-dependent glutathione peroxidase (Se-GSH-Px) in the kidneys in all dietary groups. High dietary [alpha]-tocopherol enhanced the activity of Se-GSH-Px in liver and kidney compared to the activity in mice fed the normal level of [alpha]-tocopherol. This occurred in mice exposed to CH[sub 3]-HgCl as well as in unexposed mice, and the difference between CH[sub 3]HgCl exposed and unexposed mice was not diminished. High dietary [alpha]-tocopherol increased the activity of both Se-GSH-Px and T-GSH-Px in the brain of CH[sub 3]HgCl-exposed mice. The dietary level of [beta]-carotene did not affect the activity of the two enzymes in the organs investigated. (au) (43 refs.).

Effects of alpha and gamma radiation on glass reaction in an unsaturated environment

International Nuclear Information System (INIS)

Wronkiewicz, D.J.; Young, J.E.; Bates, J.K.

1990-01-01

Radiation may effect the long-term performance of glass in an unsaturated repository site by interacting with air, water vapor, or liquid water. The present study examines (1) the effects of alpha or gamma irradiation in a water vapor environment, and (2) the influence of radiolytic products on glass reaction. Results indicate that nitric and organic acids form in an irradiated water vapor environment and are dissolved in thin films of condensed water. Glass samples exposed to these conditions react faster and have a different assemblage of secondary phases than glasses exposed to nonirradiated water vapor environments. 23 refs., 4 figs., 2 tabs

Divergent effects of 17-{beta}-estradiol on human vascular smooth muscle and endothelial cell function diminishes TNF-{alpha}-induced neointima formation

Energy Technology Data Exchange (ETDEWEB)

Nintasen, Rungrat [Division of Cardiovascular Medicine, Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds LS2 9JT (United Kingdom); Multidisciplinary Cardiovascular Research Center (MCRC), University of Leeds, Leeds LS2 9JT (United Kingdom); Department of Tropical Pathology, Faculty of Tropical Medicine, Mahidol University (Thailand); Riches, Kirsten; Mughal, Romana S. [Division of Cardiovascular Medicine, Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds LS2 9JT (United Kingdom); Multidisciplinary Cardiovascular Research Center (MCRC), University of Leeds, Leeds LS2 9JT (United Kingdom); Viriyavejakul, Parnpen; Chaisri, Urai; Maneerat, Yaowapa [Department of Tropical Pathology, Faculty of Tropical Medicine, Mahidol University (Thailand); Turner, Neil A. [Division of Cardiovascular Medicine, Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds LS2 9JT (United Kingdom); Multidisciplinary Cardiovascular Research Center (MCRC), University of Leeds, Leeds LS2 9JT (United Kingdom); Porter, Karen E., E-mail: medkep@leeds.ac.uk [Division of Cardiovascular Medicine, Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds LS2 9JT (United Kingdom); Multidisciplinary Cardiovascular Research Center (MCRC), University of Leeds, Leeds LS2 9JT (United Kingdom)

2012-04-20

Highlights: Black-Right-Pointing-Pointer TNF-{alpha} augments neointimal hyperplasia in human saphenous vein. Black-Right-Pointing-Pointer TNF-{alpha} induces detrimental effects on endothelial and smooth muscle cell function. Black-Right-Pointing-Pointer Estradiol exerts modulatory effects on TNF-induced vascular cell functions. Black-Right-Pointing-Pointer The modulatory effects of estradiol are discriminatory and cell-type specific. -- Abstract: Coronary heart disease (CHD) is a condition characterized by increased levels of proinflammatory cytokines, including tumor necrosis factor-{alpha} (TNF-{alpha}). TNF-{alpha} can induce vascular endothelial cell (EC) and smooth muscle cell (SMC) dysfunction, central events in development of neointimal lesions. The reduced incidence of CHD in young women is believed to be due to the protective effects of estradiol (E2). We therefore investigated the effects of TNF-{alpha} on human neointima formation and SMC/EC functions and any modulatory effects of E2. Saphenous vein (SV) segments were cultured in the presence of TNF-{alpha} (10 ng/ml), E2 (2.5 nM) or both in combination. Neointimal thickening was augmented by incubation with TNF-{alpha}, an effect that was abolished by co-culture with E2. TNF-{alpha} increased SV-SMC proliferation in a concentration-dependent manner that was optimal at 10 ng/ml (1.5-fold increase), and abolished by E2 at all concentrations studied (1-50 nM). Surprisingly, E2 itself at low concentrations (1 and 5 nM) stimulated SV-SMC proliferation to a level comparable to that of TNF-{alpha} alone. SV-EC migration was significantly impaired by TNF-{alpha} (42% of control), and co-culture with E2 partially restored the ability of SV-EC to migrate and repair the wound. In contrast, TNF-{alpha} increased SV-SMC migration by 1.7-fold, an effect that was completely reversed by co-incubation with E2. Finally, TNF-{alpha} potently induced ICAM-1 and VCAM-1 expression in both SV-EC and SV-SMC. However there

Alpha-particle energy spectra measured at forward angles in heavy-ion-induced reactions

International Nuclear Information System (INIS)

Borcea, C.; Cierlic, E.; Kalpakchieva, R.; Oganessian, Yu.Ts.; Penionzhkevich, Yu.E.

1980-01-01

Energy spectra have been measured for α-particles emitted in the bombardment of 159 Tb, 181 Ta, 197 Au, and 232 Th nuclei by 20 Ne, 22 Ne, and 40 Ar projectiles. The reaction products emitted in the angular range (0+-2)deg relative to the beam direction were analyzed using a magnetic spectrometer and detected by means of a semiconductor ΔE-E telescope. It was found that in all cases the experimentally measured maximum α-particle energy almost amounts to the maximum possible value calculated from the reaction energy balance for a two-body exit channel. A correlation was found between the measured absolute cross section in different target-projectile combinations and the α-particle binding energy in the target nuclei. On the basis of the obtained results a conclusion has been drawn that the α-particles are emitted in the early stage of the reaction

Agonist-induced affinity alterations of a central nervous system. cap alpha. -bungarotoxin receptor

Energy Technology Data Exchange (ETDEWEB)

Lukas, R.J.; Bennett, E.L.

1979-01-01

The ability of cholinergic agonists to block the specific interaction of ..cap alpha..-bungarotoxin (..cap alpha..-Bgt) with membrane-bound sites derived from rat brain is enhanced when membranes are preincubated with agonist. Thus, pretreatment of ..cap alpha..-Bgt receptors with agonist (but not antagonist) causes transformation of sites to a high-affinity form toward agonist. This change in receptor state occurs with a half-time on the order of minutes, and is fully reversible on dilution of agonist. The results are consistent with the identity of ..cap alpha..-Bgt binding sites as true central nicotinic acetylcholine receptors. Furthermore, this agonist-induced alteration in receptor state may represent an in vitro correlate of physiological desensitization. As determined from the effects of agonist on toxin binding isotherms, and on the rate of toxin binding to specific sites, agonist inhibition of toxin binding to the high-affinity state is non-competitive. This result suggests that there may exist discrete toxin-binding and agonist-binding sites on central toxin receptors.

Synthesis and antimicrobial evaluation of new 3-alkyl/aryl-2-[((alpha,alpha-diphenyl-alpha-hydroxy)acetyl)hydrazono]-5-methyl-4-thiazolidinones.

Science.gov (United States)

Güzeldemirci, Nuray Ulusoy; Ilhan, Eser; Küçükbasmaci, Omer; Satana, Dilek

2010-01-01

New 4-thiazolidinone derivatives of benzilic acid (alpha,alpha-diphenyl-alpha-hydroxyacetic acid) have been synthesized and evaluated for antibacterial and antifungal activities. The reaction of 1- (alpha,alpha-diphenyl-alpha-hydroxy)acetyl-4-alkyl/arylthiosemicarbazides with ethyl 2-bromopropionate gave 3-alkyl/aryl-2-[((alpha,alpha-diphenyl-alpha-hydroxy)acetyl)hydrazono]-5-methyl-4-thiazolidinone derivatives. Their antibacterial and antifungal activities were evaluated against S. aureus ATCC 29213, P. aeruginosa ATCC 27853, E. coli ATCC 25922, C. albicans ATCC 10231, C. parapsilosis ATCC 22019, C. krusei ATCC 6258, T. mentagrophytes var. erinacei NCPF 375, M. gypseum NCPF 580 and T. tonsurans NCPF 245. 3e, 3f, 3g and 3h showed the highest antibacterial activity. Particularly 3a and 3e showed the highest antifungal activities against C. parapsilosis ATCC 22019, T. tonsurans NCPF 245 and M. gypseum NCPF 580.

Ion-beam-induced reactions in metal-thin-film-/BP system

International Nuclear Information System (INIS)

Kobayashi, N.; Kumashiro, Y.; Revesz, P.; Mayer, J.W.

1989-01-01

Ion-beam-induced reactions in Ni thin films on BP(100) have been investigated and compared with the results of the thermal reaction. The full reaction of Ni layer with BP induced by energetic heavy ion bombardments (600 keV Xe) was observed at 200degC and the formation of the crystalline phase corresponding to a composition of Ni 4 BP was observed. Amorphous layer with the same composition was formed by the bombardments below RT. For thermally annealed samples the reaction of the Ni layer on BP started at temperatures between 350degC and 400degC and full reaction was observed at 450degC. Metal-rich ternary phase or mixed binary phase is thought to be the first crystalline phase formed both in the ion-beam-induced and in the thermally induced reactions. The crystalline phase has the same composition and X-ray diffraction pattern both for ion-beam-induced and thermal reactions. Linear dependence of the reacted thickness on the ion fluence was also observed. The authors would like to express their sincere gratitude to Jian Li and Shi-Qing Wang for X-ray diffraction measurements at Cornell University. One of the authors (N.K.) acknowledge the Agency of Science and Technology of Japan for the financial support of his stay at Cornell. We also acknowledge Dr. H. Tanoue at ETL for his help in ion bombardment experiments. (author)

Shrink-induced graphene sensor for alpha-fetoprotein detection with low-cost self-assembly and label-free assay

Science.gov (United States)

Sando, Shota; Zhang, Bo; Cui, Tianhong

2017-12-01

Combination of shrink induced nano-composites technique and layer-by-layer (LbL) self-assembled graphene challenges controlling surface morphology. Adjusting shrink temperature achieves tunability on graphene surface morphology on shape memory polymers, and it promises to be an alternative in fields of high-surface-area conductors and molecular detection. In this study, self-assembled graphene on a shrink polymer substrate exhibits nanowrinkles after heating. Induced nanowrinkles on graphene with different shrink temperature shows distinct surface roughness and wettability. As a result, it becomes more hydrophilic with higher shrink temperatures. The tunable wettability promises to be utilized in, for example, microfluidic devices. The graphene on shrink polymer also exhibits capability of being used in sensing applications for pH and alpha-fetoprotein (AFP) detection with advantages of label free and low cost, due to self-assembly technique, easy functionalization, and antigen-antibody reaction on graphene surface. The detection limit of AFP detection is down to 1 pg/mL, and therefore the sensor also has a significant potential for biosensing as it relies on low-cost self-assembly and label-free assay.

17-AAG, a Hsp90 inhibitor, attenuates the hypoxia-induced expression of SDF-1alpha and ILK in mouse RPE cells.

Science.gov (United States)

Wang, Ye Qing; Zhang, Xiao Mei; Wang, Xiao Dan; Wang, Bin Jie; Wang, Wei

2010-03-01

The aim of this study was to investigate the changes of SDF-1alpha and ILK expression in mouse retinal pigment epithelium (RPE) cells in response to hypoxia, and the effect of 17-Allylamino-17-demethoxygeldanamycin (17-AAG), a heat shock protein 90 (Hsp90) inhibitor, on the hypoxia-induced expression of SDF-1alpha and ILK. RPE cells were cultured with 200 micromol/L cobalt chloride (CoCl(2)) for different times (1, 3, 6, 12, 24, 72 h) to imitate chemical hypoxia. Pretreatment of 17-AAG was 1 h prior to hypoxic insult. Cellular viability after 17-AAG treatment was assessed by MTT assay, and the changes of SDF-1alpha and ILK expression were examined by RT-PCR and Western blot. Up-regulation of SDF-1alpha and ILK expression in response to hypoxia was observed. One hour pretreatment of 17-AAG could remarkably decreased the hypoxia-induced SDF-1alpha and ILK expression in vitro. Our results indicated that SDF-1alpha and ILK involved in the hypoxic response of RPE cells, and 1 h pretreatment of 17-AAG had an inhibitive effect on the hypoxia-induced SDF-1alpha and ILK expression.

Cobalt-mediated [3 + 2]-annulation reaction of alkenes with alpha,beta-unsaturated ketones and imines.

Science.gov (United States)

Schomaker, Jennifer M; Toste, F Dean; Bergman, Robert G

2009-08-20

The utility of cobalt dinitrosyl complexes for the [3 + 2] annulation of alkenes with unsaturated enones and ketimines has been demonstrated. Reaction of a series of cobalt dinitrosyl/alkene adducts with conjugate acceptors in the presence of Sc(OTf)(3)/LHMDS formed two new C-C bonds at the carbons alpha to the nitrosyl groups of the substrate, leading to unusual tri- and tetracycles. Retrocycloaddition of these products in the presence of norbornadiene yielded functionalized tetrasubstituted bicyclic olefins.

Evidence for fluctuations in statistical model cross sections from the study of {sup 27}Al(d,{alpha}) {sup 25}Mg reaction; Mise en evidence des fluctuations de sections efficaces du modele statistique par l'etude de la reaction {sup 27}Al(d,{alpha}) {sup 25}Mg

Energy Technology Data Exchange (ETDEWEB)

Papineau born Heller, L [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1965-06-01

A complete set of experimental data has been obtained for the reaction {sup 27}Al(d, {alpha}){sup 25}Mg for excitation energies in the compound nucleus {sup 29}Si between 19.7 and 27.4 MeV, in order to compare with the theoretical predictions of the statistical model of nuclear reactions including fluctuations. Numerical calculations of the theoretical cross sections were made and contributions to methods of analysis of fluctuating excitation functions are given. The results confirm strong evidence for statistical fluctuations in nuclear cross sections. (author) [French] On a obtenu un ensemble complet de donnees experimentales de la reaction {sup 27}Al(d, {alpha}){sup 25}Mg pour des energies d'excitation du noyau compose {sup 29}Si comprises entre 19,7 et 27,4 MeV, permettant la comparaison avec les previsions theoriques du modele statistique des reactions nucleaires dans sa version complete comprenant les fluctuations. Des calculs numeriques de sections efficaces theoriques ont ete effectues et des contributions ont ete apportees aux methodes d'analyse de fonctions d'excitation presentant des fluctuations. Les resultats ont clairement confirme l'existence de fluctuations statistiques de sections efficaces. (auteur)

Stress-induced decrease of uterine blood flow in sheep is mediated by alpha 1-adrenergic receptors.

Science.gov (United States)

Dreiling, Michelle; Bischoff, Sabine; Schiffner, Rene; Rupprecht, Sven; Kiehntopf, Michael; Schubert, Harald; Witte, Otto W; Nathanielsz, Peter W; Schwab, Matthias; Rakers, Florian

2016-09-01

Prenatal maternal stress can be transferred to the fetus via a catecholamine-dependent decrease of uterine blood flow (UBF). However, it is unclear which group of adrenergic receptors mediates this mechanism of maternal-fetal stress transfer. We hypothesized that in sheep, alpha 1-adrenergic receptors may play a key role in catecholamine mediated UBF decrease, as these receptors are mainly involved in peripheral vasoconstriction and are present in significant number in the uterine vasculature. After chronic instrumentation at 125 ± 1 days of gestation (dGA; term 150 dGA), nine pregnant sheep were exposed at 130 ± 1 dGA to acute isolation stress for one hour without visual, tactile, or auditory contact with their flockmates. UBF, blood pressure (BP), heart rate (HR), stress hormones, and blood gases were determined before and during this isolation challenge. Twenty-four hours later, experiments were repeated during alpha 1-adrenergic receptor blockage induced by a continuous intravenous infusion of urapidil. In both experiments, ewes reacted to isolation with an increase in serum norepinephrine, cortisol, BP, and HR as typical signs of activation of sympatho-adrenal and the hypothalamic-pituitary-adrenal axis. Stress-induced UBF decrease was prevented by alpha 1-adrenergic receptor blockage. We conclude that UBF decrease induced by maternal stress in sheep is mediated by alpha 1-adrenergic receptors. Future studies investigating prevention strategies of impact of prenatal maternal stress on fetal health should consider selective blockage of alpha 1-receptors to interrupt maternal-fetal stress transfer mediated by utero-placental malperfusion.

Total synthesis of (+/-)-taiwaniaquinol B via a domino intramolecular friedel-crafts acylation/carbonyl alpha-tert-alkylation reaction.

Science.gov (United States)

Fillion, Eric; Fishlock, Dan

2005-09-28

The first synthesis of taiwaniaquinol B, a 6-nor-5(6-->7)abeoabietane-type diterpenoid exhibiting the uncommon fused 6-5-6 tricyclic carbon skeleton, was accomplished in 15 steps. A Lewis acid-promoted tandem intramolecular Friedel-Crafts/carbonyl alpha-tert-alkylation reaction was exploited as the core strategy for the synthesis of the sterically congested 1-indanone-containing tricyclic structure. This multiple carbon-carbon bond forming reaction exploits the unique reactivity of Meldrum's acid. The facile precursor synthesis makes this a useful methodology for the expedient modification and assembly of sterically congested 1-indanone-containing ring systems.

Vinculin but not alpha-actinin is a target of PKC phosphorylation during junctional assembly induced by calcium

DEFF Research Database (Denmark)

Perez-Moreno, M; Avila, A; Islas, S

1998-01-01

and alpha-actinin, two actin binding proteins of the adherent junctions. We found that during the junctional sealing induced by Ca2+, both proteins move towards the cell periphery and, while there is a significant increase in the phosphorylation of vinculin, alpha-actinin remains unchanged. The increased...

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

DEFF Research Database (Denmark)

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

2005-01-01

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 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 protocol....... By using TNF-alpha receptor (TNFR) knock-out mice, we demonstrated that the potentiation of AMPA-induced toxicity by TNF-alpha involves TNF receptor-1, whereas the neuroprotective effect is mediated by TNF receptor-2. AMPA exposure was associated with activation and proliferation of microglia as assessed...

Interaction of a gibberellin-induced factor with the upstream region of an alpha-amylase gene in rice aleurone tissue.

OpenAIRE

Ou-Lee, T M; Turgeon, R; Wu, R

1988-01-01

The interaction between the DNA sequences of an alpha-amylase (EC 3.2.1.1) gene and a tissue-specific factor induced in rice (Oryza sativa L.) aleurone tissue by gibberellin was studied. DNA mobility-shift during electrophoresis indicated that a 500-base-pair sequence (HS500) of a rice alpha-amylase genomic clone (OSamy-a) specifically interacted with a factor from gibberellin-induced rice aleurone tissue. The amount of complex formed between the HS500 DNA fragment and the gibberellin-induced...

Neutron-induced capture cross sections via the surrogate reaction method

International Nuclear Information System (INIS)

Boutoux, G.; Jurado, B.; Aiche, M.; Barreau, G.; Capellan, N.; Companis, I.; Czajkowski, S.; Dassie, D.; Haas, B.; Mathieu, L.; Meot, V.; Bail, A.; Bauge, E.; Daugas, J. M.; Faul, T.; Gaudefroy, L.; Morel, P.; Pillet, N.; Roig, O.; Romain, P.; Taieb, J.; Theroine, C.; Burke, J.T.; Companis, I.; Derkx, X.; Gunsing, F.; Matea, I.; Tassan-Got, L.; Porquet, M.G.; Serot, O.

2011-01-01

The surrogate reaction method is an indirect way of determining cross sections for nuclear reactions that proceed through a compound nucleus. This technique enables neutron-induced cross sections to be extracted for nuclear reactions on short-lived unstable nuclei that otherwise can not be measured. This technique has been successfully applied to determine the neutron-induced fission cross sections of several short-lived nuclei. In this work, we investigate whether this powerful technique can also be used to determine of neutron-induced capture cross sections. For this purpose we use the surrogate reaction 174 Yb( 3 He, pγ) 176 Lu to infer the well known 175 Lu(n, γ) cross section and compare the results with the directly measured neutron-induced data. This surrogate experiment has been performed in March 2010. The experimental technique used and the first preliminary results will be presented. (authors)

Chemical reactivity of {alpha}-isosaccharinic acid in heterogeneous alkaline systems

Energy Technology Data Exchange (ETDEWEB)

Glaus, M. A.; Loon, L. R. Van

2009-05-15

Cellulose degradation under alkaline conditions is of relevance for the mobility of many radionuclides in the near-field of a cementitious repository for radioactive waste, because metal-binding degradation products may be formed. Among these, {alpha}- isosaccharinic acid ({alpha}-ISA) is the strongest complexant. The prediction of the equilibrium concentration of {alpha}-ISA in cement pore water is therefore an important step in the assessment of the influence of cellulose degradation products on the speciation of radionuclides in such environments. The present report focuses on possible chemical transformation reactions of {alpha}-ISA in heterogeneous alkaline model systems containing either Ca(OH){sub 2} or crushed hardened cement paste. The transformation reactions were monitored by measuring the concentration of {alpha}-ISA by high performance anion exchange chromatography and the formation of reaction products by high performance ion exclusion chromatography. The overall loss of organic species from solution was monitored by measuring the concentration of non-purgeable organic carbon. The reactions were examined in diluted and compacted suspensions, at either 25 {sup o}C or 90 {sup o}C, and under anaerobic atmospheres obtained by various methods. It was found that {alpha}-ISA was transformed under all conditions tested to some extent. Reaction products, such as glycolate, formate, lactate and acetate, all compounds with less complexing strength than {alpha}-ISA, were detected. The amount of reaction products identified by the chromatographic technique applied was {approx} 50 % of the amount of {alpha}-ISA reacted. Sorption of {alpha}-ISA to Ca(OH){sub 2} contributed only to a minor extent to the loss of {alpha}-ISA from the solution phase. As the most important conclusion of the present work it was demonstrated that the presence of oxidising agents had a distinctive influence on the turnover of {alpha}-ISA. Under aerobic conditions {alpha}-ISA was

Radiation-induced linking reactions in polyethylene

International Nuclear Information System (INIS)

Zoepfl, F.J.

1983-01-01

Three types of measurements are reported relating to chemical reactions in polyethylene induced by ionizing radiation: 1) viscometric and low-angle laser light scattering measurements to determine the effect of a radical scavenger on the yield of links; 2) calorimetric measurements to determine the effect of radiation-induced linking on the melting behavior of polyethylene; and 3) high-resolution solution carbon 13 nuclear magnetic resonance (NMR) spectrometry measurements to determine the nature of the links and the method of their formation. The NMR results present the first direct detection of radiation-induced long-chain branching (Y links) in polyethylene, and place an apparent upper limit on the yield of H-shaped crosslinks that are formed when polyethylene is irradiated to low absorbed doses. The effect of radiation-induced linking on the melting behavior of polyethylene was examined using differential scanning calorimetry (DSC). It was found that radiation-induced links do not change the heat of fusion of polythylene crystals, but decrease the melt entropy and increase the fold surface free energy per unit area of the crystals. The carbon 13 NMR results demonstrate that long-chain branches (Y links) are formed much more frequently than H-shaped crosslinks at low absorbed doses. The Y links are produced by reactions of alkyl free radicals with terminal vinyl groups in polyethylene

Relative workload determines exercise-induced increases in PGC-1alpha mRNA

DEFF Research Database (Denmark)

Nordsborg, Nikolai Baastrup; Lundby, Carsten; Leick, Lotte

2010-01-01

INTRODUCTION:: The hypothesis that brief intermittent exercise induced increases in human skeletal muscle metabolic mRNA is dependent on relative workload was investigated. METHODS:: Trained (n=10) and untrained (n=8) subjects performed exhaustive intermittent cycling exercise (4x4 min @ 85% of VO2...... peak, interspersed by 3 min). Trained subjects also performed the intermittent exercise at the same absolute workload as untrained, corresponding to 70% of VO2 peak (n=6). RESULTS:: Exercise at 85% of VO2 peak elevated (P... and untrained, respectively. PGC-1alpha mRNA expression was increased (Pelevated (3.1+/-0.7 mM) and PGC-1alpha mRNA content was less (P

Alpha particle induced soft errors in NMOS RAMs: a review

International Nuclear Information System (INIS)

Carter, P.M.; Wilkins, B.R.

1987-01-01

The paper aims to explain the alpha particle induced soft error phenomenon using the NMOS dynamic random access memory (RAM) as a model. It discusses some of the many techniques experimented with by manufacturers to overcome the problem, and gives a review of the literature covering most aspects of soft errors in dynamic RAMs. Finally, the soft error performance of current dynamic RAM and static RAM products from several manufacturers are compared. (author)

Producing a compound Nucleus via Inelastic Scattering: The 90Zr(alpha,alpha')90Zr* Case

Energy Technology Data Exchange (ETDEWEB)

Escher, J E; Dietrich, F S

2008-05-23

In a Surrogate reaction a compound nucleus is produced via a direct reaction (pickup, stripping, or inelastic scattering). For a proper application of the Surrogate approach it is necessary to predict the resulting angular momentum and parity distribution in the compound nucleus. A model for determining these distributions is developed for the case of inelastic alpha scattering off a spherical nucleus. The focus is on obtaining a first, simple description of the direct-reaction process that produces the compound nucleus and on providing the basis for a more complete treatment of the problem. The approximations employed in the present description are discussed and the extensions required for a more rigorous treatment of the problem are outlined. To illustrate the formalism, an application to {sup 90}Zr({alpha},{alpha}{prime}){sup 90}Zr* is presented.

Dynamics of synchrotron VUV-induced intracluster reactions

Energy Technology Data Exchange (ETDEWEB)

Grover, J.R. [Brookhaven National Laboratory, Upton, NY (United States)

1993-12-01

Photoionization mass spectrometry (PIMS) using the tunable vacuum ultraviolet radiation available at the National Synchrotron Light Source is being exploited to study photoionization-induced reactions in small van der Waals mixed complexes. The information gained includes the observation and classification of reaction paths, the measurement of onsets, and the determination of relative yields of competing reactions. Additional information is obtained by comparison of the properties of different reacting systems. Special attention is given to finding unexpected features, and most of the reactions investigated to date display such features. However, understanding these reactions demands dynamical information, in addition to what is provided by PIMS. Therefore the program has been expanded to include the measurement of kinetic energy release distributions.

TNF-{alpha} promotes human retinal pigment epithelial (RPE) cell migration by inducing matrix metallopeptidase 9 (MMP-9) expression through activation of Akt/mTORC1 signaling

Energy Technology Data Exchange (ETDEWEB)

Wang, Cheng-hu; Cao, Guo-Fan [The Affiliated Eye Hospital of Nanjing Medical University, Nanjing 210029 (China); Jiang, Qin, E-mail: Jqin710@vip.sina.com [The Affiliated Eye Hospital of Nanjing Medical University, Nanjing 210029 (China); Yao, Jin, E-mail: dryaojin@yahoo.com [The Affiliated Eye Hospital of Nanjing Medical University, Nanjing 210029 (China)

2012-08-17

Highlights: Black-Right-Pointing-Pointer TNF-{alpha} induces MMP-9 expression and secretion to promote RPE cell migration. Black-Right-Pointing-Pointer MAPK activation is not critical for TNF-{alpha}-induced MMP-9 expression. Black-Right-Pointing-Pointer Akt and mTORC1 signaling mediate TNF-{alpha}-induced MMP-9 expression. Black-Right-Pointing-Pointer SIN1 knockdown showed no significant effect on MMP-9 expression by TNF-{alpha}. -- Abstract: Tumor necrosis factor-alpha (TNF-{alpha}) promotes in vitro retinal pigment epithelial (RPE) cell migration to initiate proliferative vitreoretinopathy (PVR). Here we report that TNF-{alpha} promotes human RPE cell migration by inducing matrix metallopeptidase 9 (MMP-9) expression. Inhibition of MMP-9 by its inhibitor or its neutralizing antibody inhibited TNF-{alpha}-induced in vitro RPE cell migration. Reversely, exogenously-added active MMP-9 promoted RPE cell migration. Suppression Akt/mTOR complex 1(mTORC1) activation by LY 294002 and rapamycin inhibited TNF-{alpha}-mediated MMP-9 expression. To introduce a constitutively active Akt (CA-Akt) in cultured RPE cells increased MMP-9 expression, and to block mTORC1 activation by rapamycin inhibited its effect. RNA interference (RNAi)-mediated silencing of SIN1, a key component of mTOR complex 2 (mTORC2), had no effect on MMP-9 expression or secretion. In conclusion, this study suggest that TNF-{alpha} promotes RPE cell migration by inducing MMP-9 expression through activation of Akt/ mTORC1, but not mTORC2 signaling.

alpha-Tocopheryl succinate promotes selective cell death induced by vitamin K3 in combination with ascorbate.

Science.gov (United States)

Tomasetti, M; Strafella, E; Staffolani, S; Santarelli, L; Neuzil, J; Guerrieri, R

2010-04-13

A strategy to reduce the secondary effects of anti-cancer agents is to potentiate the therapeutic effect by their combination. A combination of vitamin K3 (VK3) and ascorbic acid (AA) exhibited an anti-cancer synergistic effect, associated with extracellular production of H(2)O(2) that promoted cell death. The redox-silent vitamin E analogue alpha-tocopheryl succinate (alpha-TOS) was used in combination with VK3 and AA to evaluate their effect on prostate cancer cells. Prostate cancer cells were sensitive to alpha-TOS and VK3 treatment, but resistant to AA upto 3.2 mM. When combined, a synergistic effect was found for VK3-AA, whereas alpha-TOS-VK3 and alpha-TOS-AA combination showed an antagonist and additive effect, respectively. However, sub-lethal doses of AA-VK3 combination combined with a sub-toxic dose of alpha-TOS showed to induce efficient cell death that resembles autoschizis. Associated with this cell demise, lipid peroxidation, DNA damage, cytoskeleton alteration, lysosomal-mitochondrial perturbation, and release of cytochrome c without caspase activation were observed. Inhibition of lysosomal proteases did not attenuate cell death induced by the combined agents. Furthermore, cell deaths by apoptosis and autoschizis were detected. These finding support the emerging idea that synergistic combinations of some agents can overcome toxicity and other side-effects associated with high doses of single drugs creating the opportunity for therapeutically relevant selectivity.

Dynamical isospin effects in nucleon-induced reactions

International Nuclear Information System (INIS)

Ou Li; Li Zhuxia; Wu Xizhen

2008-01-01

The isospin effects in proton-induced reactions on isotopes of 112-132 Sn and the corresponding β-stable isobars are studied by means of the improved quantum molecular dynamics model and some sensitive probes for the density dependence of the symmetry energy at subnormal densities are proposed. The beam energy range is chosen to be 100-300 MeV. Our study shows that the system size dependence of the reaction cross sections for p+ 112-132 Sn deviates from the Carlson's empirical expression obtained by fitting the reaction cross sections for proton on nuclei along the β-stability line and sensitively depends on the stiffness of the symmetry energy. We also find that the angular distribution of elastic scattering for p+ 132 Sn at large impact parameters is very sensitive to the density dependence of the symmetry energy, which is uniquely due to the effect of the symmetry potential with no mixture of the effect from the isospin dependence of the nucleon-nucleon cross sections. The isospin effects in neutron-induced reactions are also studied and it is found that the effects are just opposite to that in proton-induced reactions. We find that the difference between the peaks of the angular distributions of elastic scattering for p+ 132 Sn and n+ 132 Sn at E p,n =100 MeV and b=7.5 fm is positive for soft symmetry energy U sym sf and negative for super-stiff symmetry energy U sym nlin and close to zero for linear density dependent symmetry energy U sym lin , which seems very useful for constraining the density dependence of the symmetry energy at subnormal densities

Experimental and Theoretical Investigation of Shock-Induced Reactions in Energetic Materials

Energy Technology Data Exchange (ETDEWEB)

Kay, Jeffrey J. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Park, Samuel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kohl, Ian Thomas [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Knepper, Robert [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Farrow, Darcie [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Tappan, Alexander S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-09-01

In this work, shock-induced reactions in high explosives and their chemical mechanisms were investigated using state-of-the-art experimental and theoretical techniques. Experimentally, ultrafast shock interrogation (USI, an ultrafast interferometry technique) and ultrafast absorption spectroscopy were used to interrogate shock compression and initiation of reaction on the picosecond timescale. The experiments yielded important new data that appear to indicate reaction of high explosives on the timescale of tens of picoseconds in response to shock compression, potentially setting new upper limits on the timescale of reaction. Theoretically, chemical mechanisms of shock-induced reactions were investigated using density functional theory. The calculations generated important insights regarding the ability of several hypothesized mechanisms to account for shock-induced reactions in explosive materials. The results of this work constitute significant advances in our understanding of the fundamental chemical reaction mechanisms that control explosive sensitivity and initiation of detonation.

Elevated sodium chloride concentrations enhance the bystander effects induced by low dose alpha-particle irradiation

Energy Technology Data Exchange (ETDEWEB)

Han Wei; Zhu Lingyan; Jiang Erkang; Wang Jun; Chen Shaopeng; Bao Linzhi; Zhao Ye; Xu An; Yu Zengliang [Key Laboratory of Ion Beam Bioengineering, Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Wu Lijun [Key Laboratory of Ion Beam Bioengineering, Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)], E-mail: ljw@ipp.ac.cn

2007-11-01

Previous studies have shown that high NaCl can be genotoxic, either alone or combined with irradiation. However, little is known about the relationship between environmental NaCl at elevated conditions and radiation-induced bystander effects (RIBE). RIBE, which has been considered as non-targeted bystander responses, has been demonstrated to occur widely in various cell lines. In the present study, RIBE under the elevated NaCl culture condition was assessed in AG 1522 cells by both the induction of {gamma}-H2AX, a reliable marker of DNA double-strand break (DSB) for the early process (<1 h post irradiation), and the generation of micronuclei (MN), a sensitive marker for relative long process of RIBE. Our results showed that in the absence of irradiation, NaCl at elevated concentration such as 8.0, 9.0 and 10.0 g/L did not significantly increase the frequency of {gamma}-H2AX foci-positive cells and the number of foci per positive cell comparing with that NaCl at a normal concentration (6.8 g/L). However, with 0.2 cGy {alpha}-particle irradiation, the induced fraction of {gamma}-H2AX foci-positive cells and the number of induced {gamma}-H2AX foci per positive cell were significantly increased in both irradiated and adjacent non-irradiated regions. Similarly, the induction of MN by 0.2 cGy {alpha}-particle irradiation also increased with the elevated NaCl concentrations. With N{sup G}-methyl-L-arginine, an inhibitor of nitric oxide synthase, the induced fraction of foci-positive cells was effectively inhibited both in 0.2 cGy {alpha}-particle irradiated and adjacent non-irradiated regions under either normal or elevated NaCl conditions. These results suggested that the cultures with elevated NaCl medium magnified the damage effects induced by the low dose {alpha}-particle irradiation and nitric oxide generated by irradiation was also very important in this process.

Bystander effect-induced mutagenicity in HPRT locus of CHO cells following BNCT neutron irradiation: Characteristics of point mutations by sequence analysis

Energy Technology Data Exchange (ETDEWEB)

Kinashi, Yuko [Research Reactor Institute, Kyoto University, Kumatori-cho, Sennan-gun, Osaka (Japan)], E-mail: kinashi@rri.kyoto-u.ac.jp; Suzuki, Minoru; Masunaga, Shinichiro; Ono, Koji [Research Reactor Institute, Kyoto University, Kumatori-cho, Sennan-gun, Osaka (Japan)

2009-07-15

To investigate bystander mutagenic effects induced by alpha particles during boron neutron capture therapy (BNCT), we mixed cells that were electroporated with borocaptate sodium (BSH), which led to the accumulation of {sup 10}B inside the cells, with cells that did not contain the boron compound. BSH-containing cells were irradiated with {alpha} particles produced by the {sup 10}B(n,{alpha}){sup 7}Li reaction, whereas cells without boron were only affected by the {sup 1}H(n,{gamma}){sup 2}H and {sup 14}N(n,{rho}){sup 14}C reactions. The frequency of mutations induced in the hypoxanthine-guanine phosphoribosyltransferase (HPRT) locus was examined in Chinese hamster ovary (CHO) cells irradiated with neutrons (Kyoto University Research Reactor: 5 MW). Neutron irradiation of 1:1 mixtures of cells with and without BSH resulted in a survival fraction of 0.1, and the cells that did not contain BSH made up 99.4% of the surviving cell population. Using multiplex polymerase chain reactions (PCRs), molecular structural analysis indicated that most of the mutations induced by the bystander effect were point mutations and that the frequencies of total and partial deletions induced by the bystander effect were lower than those resulting from the {alpha} particles produced by the {sup 10}B(n,{alpha}){sup 7}Li reaction or the neutron beam from the {sup 1}H(n,{gamma}){sup 2}H and {sup 14}N(n,{rho}){sup 14}C reactions. The types of point mutations induced by the BNCT bystander effect were analyzed by cloning and sequencing methods. These mutations were comprised of 65.5% base substitutions, 27.5% deletions, and 7.0% insertions. Sequence analysis of base substitutions showed that transversions and transitions occurred in 64.7% and 35.3% of cases, respectively. G:C{yields}T:A transversion induced by 8-oxo-guanine in DNA occurred in 5.9% of base substitution mutants in the BNCT bystander group. The characteristic mutations seen in this group, induced by BNCT {alpha} particles

Induced isospin mixing in direct nuclear reactions

International Nuclear Information System (INIS)

Lenske, H.

1979-07-01

The effect of charge-dependent interactions on nuclear reactions is investigated. First, a survey is given on the most important results concerning the charge dependence of the nucleon-nucleon interaction. The isospin symmetry and invariance principles are discussed. Violations of the isospin symmetry occuring in direct nuclear reactions are analysed using the soupled channel theory, the folding model and microscopic descriptions. Finally, induced isospin mixing in isospin-forbidden direct reactions is considered using the example of the inelastic scattering of deuterons on 12 C. (KBE)

ZZ RRDF-98, Cross-sections and covariance matrices for 22 neutron induced dosimetry reactions

International Nuclear Information System (INIS)

Zolotarev, K.I.; Ignatyuk, A.V.; Mahokhin, V.N.; Pashchenko, A.B.

2005-01-01

1 - Description of program or function: Format: ENDF-6 format; Number of groups: Continuous energy; Dosimetry reactions: 6-C-12(n,2n), 8-O-16(n,2n), 9-F-19(n,2n), 12-Mg-24(n,p), 22-Ti-46(n,2n), 22-Ti-46(n,p), 22-Ti-47(n,x), 22-Ti-48(n,p), 22-Ti-48(n,x), 22-Ti-49(n,x), 23-V-51(n,alpha), 26-Fe-54(n,2n), 26-Fe-54(n,alpha), 26-Fe-56(n,p), 27-Co-59(n,alpha), 29-Cu-63(n,alpha), 33-As-75(n,2n), 41-Nb-93(n,2n), 41-Nb-93(n,n'), 45-Rh-103(n,n'), 49-In-115(n,n'), 59-Pr-141(n,2n); Origin: Russian Federation; Weighting spectrum: None. RRDF-98 contains original evaluations of cross section data performed at the Institute of Physics and Power Engineering, Obninsk, for 22 neutron induced dosimetry reactions. The dataset also contains the corresponding covariance matrices. 2 - Methods: The evaluation of excitation functions was performed on the basis of statistical analysis of corrected experimental data in the framework of generalized least squares method and taking into account the results of optical-statistical STAPRE and GNASH calculations. The experimental cross section data including the most recent results were critically reviewed and processed in this study. If necessary, the data were normalized in order to make adjustments in relevant cross sections and decay schemes. The covariance matrices were prepared and the evaluated cross section data are presented in ENDF-6 format (Files 3, 33). For estimation of correlations between experimental data the total uncertainties of measured cross sections have been separated into statistical and systematic parts and correlation coefficients between components of systematic parts were assigned according to information given in the original publications and EXFOR library. Then the correlation matrix of cross sections measured within one experiment was calculated and approximated by matrix with a constant (average) correlation coefficient. The overall correlation matrix was composed of such sub-matrices in the assumption that the cross

Different signaling pathways induced by alpha-CD3 monoclonal antibody versus alloantigen on the basis of differential ornithine sensitivity.

Science.gov (United States)

Mehrotra nee Tandon, P; Lind, D S; Bear, H D; Susskind, B M

1992-08-01

Previously we reported that 10 mM ornithine (Orn) selectively inhibits the development of CD8+ CTL in MLC. Herein we show that induction by alpha-CD3 mAb of CD8+ killer cells which manifest antibody-redirected cytotoxicity (ARC) of FcR+ targets is not Orn sensitive. Orn resistance was independent of activation kinetics or alpha-CD3 mAb concentration. alpha-CD3 mAb added to the cytotoxicity assay did not reveal a cytolytic potential in CTL from an Orn-treated MLC when the target cells bore both the inducing alloantigen and FcR. Addition of alpha-CD3 mAb to MLC failed to overcome Orn inhibition of CTL and yet induced ARC activity in the same culture. Expression of mRNA for pore-forming proteins (PFP) and granzyme B was inhibited by Orn in CTL but not in ARC killer cells. Our results demonstrate differences in the T cell activation process stimulated by alloantigen or alpha-CD3 mAb.

MicroRNA-195 induced apoptosis in hypoxic chondrocytes by targeting hypoxia-inducible factor 1 alpha.

Science.gov (United States)

Bai, R; Zhao, A-Q; Zhao, Z-Q; Liu, W-L; Jian, D-M

2015-02-01

The chondrocytes, the resident cells of cartilage, are maintained and take effects in the whole life upon chronic hypoxic exposure, which hypoxia-inducible factor 1 alpha (HIF-1α) play pivotal roles in response to. Dysregulation of some microRNA (miRNAs) have also been identified to be involved in hypoxia-related physiologic and pathophysiologic responses in some tissues or cell lines. However, the mechanism of miRNAs reponse to hypoxia remain largely unknown in chondrocytes, including the microRNA-195 (miR-195). AIM To investigate the effects of microRNAs (miRNAs) and hypoxia-inducible factor 1 alpha (HIF-1α) on chondrocytes in physiologic environment. We compared the expression of miR-195 and HIF-1α mRNA on hypoxia with that on normoxia in ATDC 5 cells by qRT-PCR. Further experiments was performed to confirmed the relationships of miR-195 and HIF-1α by bioinformatics analysis and dual reporter gene assay. we also assessed the effect of miR-195 on apoptosis in hypoxic ATDC 5 cells by transfect with miR-195 mimics. It was found the downregulated miR-195 and upregulated HIF-1α were present in hypoxic ATDC 5 cells. miR-195 negatively regulated HIF-1α by targeting its 3'-untranslated region. Moreover, the founding indicated miR-195 greatly increased apoptosis and downregulated HIF-1α mRNA occurred simultaneously in hypoxic chondrocytes. We concluded that miR-195 induced apoptosis in hypoxic chondrocytes by directly targeting HIF-1α.

Testing an ionization chamber with gaseous samples and measurements of the (n, alpha) reaction cross sections

CERN Document Server

Gledenov, Yu M; Salatskii, V I; Sedyshev, P V; Andrzejewski, J; Szalanski, P

1999-01-01

A new ionization chamber with gaseous samples (GIC) has been designed and tested on the thermal and resonance neutron beams of FLNP's neutron sources. The exposed gas volume serves as a target for neutrons. The obtained thermal cross sections for the sup 1 sup 7 O(n, alpha) sup 1 sup 4 C, sup 2 sup 1 Ne(n, alpha) sup 1 sup 8 O and sup 3 sup 6 Ar(n, alpha) sup 3 sup 3 S reactions are (233+-12) mb, (0.18+-0.09) mb and (5.43+-0.27) mb, respectively. These measurements have been performed on a pure beam of thermal neutrons from the high flux reactor IBR-2; and they demonstrated high efficiency and reliability of the method. Compared to samples on substrates, the application of gaseous samples makes the beam background essentially lower, and what is more important, the background component is totally absent due to the absence of Li and B microimpurities in gaseous samples while they do present in the samples on substrates. The method is also applicable to measurements with resonance neutrons. The recovery capabili...

Chemical reactions induced by fast neutron irradiation

International Nuclear Information System (INIS)

Katsumura, Y.

1989-01-01

Here, several studies on fast neutron irradiation effects carried out at the reactor 'YAYOI' are presented. Some indicate a significant difference in the effect from those by γ-ray irradiation but others do not, and the difference changes from subject to subject which we observed. In general, chemical reactions induced by fast neutron irradiation expand in space and time, and there are many aspects. In the time region just after the deposition of neutron energy in the system, intermediates are formed densely and locally reflecting high LET of fast neutrons and, with time, successive reactions proceed parallel to dissipation of localized energy and to diffusion of the intermediates. Finally the reactions are completed in longer time region. If we pick up the effects which reserve the locality of the initial processes, a significant different effect between in fast neutron radiolysis and in γ-ray radiolysis would be derived. If we observe the products generated after dissipation and diffusion in longer time region, a clear difference would not be observed. Therefore, in order to understand the fast neutron irradiation effects, it is necessary to know the fundamental processes of the reactions induced by radiations. (author)

Transcriptional switch from albumin to alpha-fetoprotein and changes in transcription of other genes during carbon tetrachloride induced liver regeneration

International Nuclear Information System (INIS)

Panduro, A.; Shalaby, F.; Weiner, F.R.; Biempica, L.; Zern, M.A.; Shafritz, D.A.

1986-01-01

During liver regeneration induced by CCl 4 administration to rats, changes in the relative transcription rates of albumin and alpha-fetoprotein genes have been measured in conjunction with other liver-specific and general cellular function genes. Within 24 h following CCl 4 administration, albumin gene transcription decreases by 85%, whereas alpha-fetoprotein transcription increases from undetectable levels to 50% of that observed for albumin. These changes precede maximal [ 3 H]thymidine incorporation into DNA which peaks at 48 h. Other genes related to liver-specific functions, such as ligandin, alpha 1-antitrypsin, and cytochrome P-450's, as well as general cellular genes pro alpha 1- and pro alpha 2-collagen, beta-actin, and alpha-tubulin, respond in kinetic patterns often distinct from each other and from albumin and alpha-fetoprotein. Changes in the steady-state levels of albumin and alpha-fetoprotein mRNA correlate with changes in transcription, but there is a lag in alpha-fetoprotein mRNA accumulation, which peaks at 72 h following CCl 4 administration. These studies indicate that reciprocal changes in albumin and alpha-fetoprotein gene transcription occur during CCl 4 -induced liver regeneration, leading to changes in the level of these specific mRNAs. These changes precede DNA synthesis and would appear to represent an alteration in differentiated function of hepatocytes in conjunction with the liver regenerative process

alpha2 adrenoceptors are involved in the regulation of the gripping-induced immobility episodes in taiep rats.

Science.gov (United States)

Eguibar, José R; Cortés, Ma Del Carmen; Valencia, Jaime; Arias-Montaño, José A

2006-10-01

In 1989 Holmgren et al. (Holmgren et al. 1989 Lab Anim Sci 39:226-228) described a new mutant rat that developed a progressive motor disturbance during its lifespan. The syndrome is characterized by a tremor in the hind limbs followed by ataxia, episodes of tonic immobility, epilepsy, and paralysis. The acronym of these symptoms (taiep) became the name of this autosomic, recessive mutant rat. The taiep rats are neurological mutant animals with a hypomyelination, followed by a progressive demyelination process. At 7-8 months of age, taiep rats develop immobility episodes (IEs) characterized by a cortical desynchronization, associated with the theta rhythm in the hippocampus and changes of the nucal electromyogram (EMG), whose pattern is like rapid-eye-movement (REM) sleep. These rats also show an altered sleep pattern with an equal REM sleep distribution. This study analyzed therole of alpha(2) adrenoceptors in the expression of gripping-induced IEs in 8-month-old male taiep rats. The alpha(2) adrenoceptor agonists clonidine and xylacine increased the frequency of gripping-induced IEs whereas the alpha(2) antagonists yohimbine and idazoxandecreased or prevented such episodes. These findings correlate with the pharmacological observations in narcoleptic dogs and humans in which alpha(2) adrenergic mechanisms are involved in the modulation of cataplexy. Unexpectedly, the repetitive administration of clonidine resulted in jumping behavior, indicative of phasic activation of extensor musculature. Taken together, our results show that alpha(2) adrenoceptors are involved in the modulation in gripping-induced IEs and after the administration of several doses of clonidine produced phasic motor activation.

The factor that determines photo-induced crystalline-state reaction

International Nuclear Information System (INIS)

Takenaka, Y.

1995-01-01

The photo-induced crystalline-state reaction of cobaloxime complexes were investigated by X-ray diffraction method. The reactivity or the reaction rate is dependent only on the volume of the reaction cavity. The hydrogen bond formation of the reactive group and the difference of the base ligand have no effect. (author)

Quasi-bound alpha resonant states populated by the 12C(6Li, d) reaction

International Nuclear Information System (INIS)

Rodrigues, M.R.D.; Borello-Lewin, T.; Miyake, H.; Horodynski-Matsushigue, L.B.; Duarte, J.L.M.; Rodrigues, C.L.; Souza, M.A.; Cunsolo, A.; Cappuzzello, F.; Foti, A.; Agodi, C.; Cavallaro, M.; Ukita, G.M.

2012-01-01

Full text: The alpha cluster phenomenon in the light nuclei structure has been the subject of a long time investigation since the proposal of the Ikeda diagrams [1]. The main purpose of the research program in progress is the investigation of this phenomenon in (xα) and (xα+n) nuclei through the ( 6 Li, d) alpha transfer reaction [2-4]. Alpha resonant states around the (4α) threshold in the nucleus 16 O are the focus of the present contribution. In fact, the importance of these resonances at the elements production in stars is recognized, as primarily pointed out by Hoyle in 12 C [6]. The existence of a rotational band with the α + 12 C (Hoyle) cluster state structure was recently demonstrated by Ohkubo and Hirabayashi [6]. In order to explore this region of interest, measurements of the 12 C( 6 Li, d) 16 O reaction up to 17 MeV of excitation at an incident energy of 25.5 MeV, have been performed employing the Sao Paulo Pelletron-Enge Split-Pole facility and the nuclear emulsion detection technique (plates Fuji G6B, 50 μm thick). Spectra associated with six scattering angles, from 5 deg to 29 deg in the laboratory frame, each one 50 cm along the focal surface, were measured. Several narrow resonances with a quasi-bound behavior embedded in the continuum were detected and the resolution of 25 keV allowed for the separation of doublets not resolved before [7,8]. The absolute cross sections and the respective deuteron angular distributions were determined and the analysis is in progress. [1] K. Ikeda et al., Prog. Theor. Phys. Suppl. E 68, 464 (1968); H. Horiuchi, K. Ikeda, and Y. Suzuki, ibid. 44, 225 (1978). [2] M.R.D.Rodrigues et al., in12th International Conference on Nuclear Reaction Mechanism, Varenna, Italy, edited by F. Cerutti and A. Ferrari , CERN Proceedings, 2010-2, pp. 331- 335. [3] T. Borello-Lewin et al., Proceedings of SOTANCP2, Brussels, Belgium 2010, edited by P. Descouvemount et al., Int. J. Mod. Mod. Phys E 20, 1018-1021 (2011). [4] T. Borello

Micellar induced regioselectivity in the two-step consecutive reaction of SO3(2-) with Br-(CH2CH2)n-Br (n=2-5).

Science.gov (United States)

Currie, Fredrik; Jarvoll, Patrik; Holmberg, Krister; Romsted, Laurence S; Gunaseelan, Krishnan

2007-08-15

High field (800 MHz) (1)H NMR was used to monitor the two-step consecutive reaction of excess SO(3)(2-) with symmetrical bifunctional alpha,omega-dibromoalkanes with butane (DBB), hexane (DBH), octane (DBO), and decane (DBD) chains in CTAB micelles at 25 degrees C. The first-order rate constant for the first substitution step for DBB and DBH is about 5 times faster than for the second, but the kinetics for DBO and DBD were not cleanly first-order. After 40 min, the solution contained about 80% of the intermediate bromoalkanesulfonate from DBB and DBH and the remainder is alkanedisulfonate and unreacted starting material. The same reactions were carried out in homogeneous MeOH/D(2)O solutions at 50 degrees C. The rate constants for all four alpha,omega-dibromoalkanes were first-order throughout the time course of the reaction and the same within +/-10%. However, because micellar solutions are organized on the nanoscale and bring together lipophilic and hydrophilic reactants into a small reaction volume at the micellar interface, they speed this substitution reaction considerably compared to reaction in MeOH/D(2)O. The CTAB micelles also induce a significant regioselectivity in product formation by speeding the first step of the consecutive reaction more than the second. The results are consistent with the bromoalkanesulfonate intermediates having a radial orientation within the micelles with the -CH(2)SO(3)(-) group in the interfacial region and the -CH(2)Br group directed into the micellar core such that the concentration of -CH(2)Br groups in the reactive zone, i.e., the micellar interface, is significantly reduced. These results provide the first example of self-assembled surfactant system altering the relative rates of the reaction steps of a consecutive reaction and, in doing so, enhancing monosubstitution of a symmetrically disubstituted species.

Influence of Alpha Tocopherol on Heat Stress-Induced Changes in the Reproductive Function of Swiss Albino Mice

International Nuclear Information System (INIS)

AlEnazi, Maher M.

2007-01-01

The present study was carried out to investigate the influence of vitamin E (alpha-tocopherol) on heat stress-induced changes in the reproduction of Swiss albino mice. The evaluated parameters include: the estrous cycle, fertility, post-implantation losses of fetuses and estimation of progesterone levels in the serum. Eight groups of experimental mice (10 each) were used. Groups 1-4 (24 degree C) consisted of a control and alpha-tocopherol (100, 200 and 400 mg/kg) treated groups. Groups 5-8 (42 degree C) consisted of a positive control and alpha-tocopherol (100, 200 and 400 mg/kg) treated group. Heat-stress reduced significantly (p > 0.001) the number of fetuses and corpora lutea. There was also a significant decrease in the mean weights of fetuses (p > 0.001) and placenta (p > 0.01) in the heat-stress group with a decrease in their serum progesterone levels (p > 0.01). Heat-stress groups treated with high doses of alpha-tocopherol 200 and 400 mg/kg, showed protection against heat-stress related abnormalities. The results showed that alpha-tocopherol plays a role in protection against hyperthermia induced changes in the estrous cycle length, infertility, post-implantation losses and depletion in the serum level of progesterone. (author)

HLA Association with Drug-Induced Adverse Reactions

Directory of Open Access Journals (Sweden)

Wen-Lang Fan

2017-01-01

Full Text Available Adverse drug reactions (ADRs remain a common and major problem in healthcare. Severe cutaneous adverse drug reactions (SCARs, such as Stevens–Johnson syndrome (SJS/toxic epidermal necrolysis (TEN with mortality rate ranges from 10% to more than 30%, can be life threatening. A number of recent studies demonstrated that ADRs possess strong genetic predisposition. ADRs induced by several drugs have been shown to have significant associations with specific alleles of human leukocyte antigen (HLA genes. For example, hypersensitivity to abacavir, a drug used for treating of human immunodeficiency virus (HIV infection, has been proposed to be associated with allele 57:01 of HLA-B gene (terms HLA-B∗57:01. The incidences of abacavir hypersensitivity are much higher in Caucasians compared to other populations due to various allele frequencies in different ethnic populations. The antithyroid drug- (ATDs- induced agranulocytosis are strongly associated with two alleles: HLA-B∗38:02 and HLA-DRB1∗08:03. In addition, HLA-B∗15:02 allele was reported to be related to carbamazepine-induced SJS/TEN, and HLA-B∗57:01 in abacavir hypersensitivity and flucloxacillin induced drug-induced liver injury (DILI. In this review, we summarized the alleles of HLA genes which have been proposed to have association with ADRs caused by different drugs.

Human LT-alpha-mediated resistance to autoimmune diabetes is induced in NOD, but not NOD-scid, mice and abrogated by IL-12.

Science.gov (United States)

Miyaguchi, S; Satoh, J; Takahashi, K; Sakata, Y; Nakazawa, T; Miyazaki, J; Toyota, T

2001-01-01

Systemic administration of human lymphotoxin-alpha (hLT-alpha) made NOD mice resistant not only to spontaneous autoimmune type 1 diabetes mellitus but also to cyclophosphamide (CY)-induced diabetes and diabetes transfer by diabetic NOD spleen cells (triple resistance). In this study we analyzed the mechanisms of hLT-alpha-induced resistance, focusing on (1) hLT-alpha-induced resistance in the pancreatic beta cell, (2) CY-resistant suppressor cells, (3) suppression of induction or function of effector cells for beta cell destruction, or (4) others. To examine the first possibility in vitro, a NOD-derived beta cell line (MIN6N) was pretreated with hLT-alpha and then mixed with diabetic NOD spleen cells and MIN6N cell viability was measured. Treatment with hLT-alpha did not protect MIN6N cells but rather enhanced cytotoxicity. Next NOD-scid mice were pretreated with hLT-alpha and then transferred with diabetic NOD spleen. All the recipients developed diabetes. These results excluded the first possibility. The second possibility was also excluded by a cotransfer experiment, in which diabetic NOD spleen cells were cotransferred to NOD-scid mice with nontreated or hLT-alpha-treated nondiabetic NOD spleens. There was no significant difference in diabetes incidence between the two groups. To observe the third possibility, spleen cells of hLT-alpha-treated triple-resistant NOD mice were transferred to NOD-scid mice. Diabetes developed in the recipients, although the onset of diabetes was slightly delayed. Finally, hLT-alpha-treated triple-resistant NOD mice developed diabetes 1 week after daily IL-12 treatment. In summary, hLT-alpha administration made NOD mice resistant to effector cells for beta cell destruction. This resistance was induced in NOD, but not in NOD-scid, mice, indicating that lymphocytes were obligatory for the resistance. However, it was not mediated by transferable suppressor cells. Because effector cells were present in hLT-alpha-treated NOD spleen and

Nucleogenic production of Ne isotopes in Earth's crust and upper mantle induced by alpha particles from the decay of U and Th

Science.gov (United States)

Leya, Ingo; Wieler, Rainer

1999-07-01

The production of nucleogenic Ne in terrestrial crust and upper mantle by alpha particles from the decay of U and Th was calculated. The calculations are based on stopping powers for the chemical compounds and thin-target cross sections. This approach is more rigorous than earlier studies using thick-target yields for pure elements, since our results are independent of limiting assumptions about stopping-power ratios. Alpha induced reactions account for >99% of the Ne production in the crust and for most of the 20,21Ne in the upper mantle. On the other hand, our 22Ne value for the upper mantle is a lower limit because the reaction 25Mg(n,α)22Ne is significant in mantle material. Production rates calculated here for hypothetical crustal and upper mantle material with average major element composition and homogeneously distributed F, U, and Th are up to 100 times higher than data presented by Kyser and Rison [1982] but agree within error limits with the results by Yatsevich and Honda [1997]. Production of nucleogenic Ne in "mean" crust and mantle is also given as a function of the weight fractions of O and F. The alpha dose is calculated by radiogenic 4He as well as by the more retentive fissiogenic 136Xe. U and Th is concentrated in certain accessory minerals. Since the ranges of alpha particles from the three decay chains are comparable to mineral dimensions, most nucleogenic Ne is produced in U- and Th-rich minerals. Therefore nucleogenic Ne production in such accessories was also calculated. The calculated correlation between nucleogenic 21Ne and radiogenic 4He agrees well with experimental data for Earth's crust and accessories. Also, the calculated 22Ne/4He ratios as function of the F concentration and the dependence of 21Ne/22Ne from O/F for zircon and apatite agree with measurements.

Alpha clustering in nuclei

International Nuclear Information System (INIS)

Hodgson, P.E.

1990-01-01

The effects of nucleon clustering in nuclei are described, with reference to both nuclear structure and nuclear reactions, and the advantages of using the cluster formalism to describe a range of phenomena are discussed. It is shown that bound and scattering alpha-particle states can be described in a unified way using an energy-dependent alpha-nucleus potential. (author)

Andrographolide down-regulates hypoxia-inducible factor-1{alpha} in human non-small cell lung cancer A549 cells

Energy Technology Data Exchange (ETDEWEB)

Lin, Hui-Hsuan [School of Medical Laboratory and Biotechnology, Chung Shan Medical University, Taichung, Taiwan (China); Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan (China); Tsai, Chia-Wen [Department of Nutrition, China Medical University, Taichung, Taiwan (China); Chou, Fen-Pi [Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung, Taiwan (China); Wang, Chau-Jong [Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan (China); Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung, Taiwan (China); Hsuan, Shu-Wen [Department of Medical Laboratory Science and Biotechnology, College of Medicine and Life Science, Chung Hwa University of Medical Technology, No.89, Wen Hwa 1st St., Rende Shiang, Tainan County 717, Taiwan (China); Wang, Cheng-Kun [E-Chyun Dermatology Clinic, No.70, Sec. 3, Jhonghua E. Rd., East District, Tainan, Taiwan (China); Chen, Jing-Hsien [Department of Medical Laboratory Science and Biotechnology, College of Medicine and Life Science, Chung Hwa University of Medical Technology, No.89, Wen Hwa 1st St., Rende Shiang, Tainan County 717, Taiwan (China)

2011-02-01

Andrographolide (Andro), a diterpenoid lactone isolated from a traditional herbal medicine Andrographis paniculata, is known to possess multiple pharmacological activities. In our previous study, Andro had been shown to inhibit non-small cell lung cancer (NSCLC) A549 cell migration and invasion via down-regulation of phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. Here we demonstrated that Andro inhibited the expression of hypoxia-inducible factor-1{alpha} (HIF-1{alpha}) in A549 cells. HIF-1{alpha} plays an important role in tumor growth, angiogenesis and lymph node metastasis of NSCLC. The Andro-induced decrease of cellular protein level of HIF-1{alpha} was correlated with a rapid ubiquitin-dependent degradation of HIF-1{alpha}, and was accompanied by increased expressions of hydroxyl-HIF-1{alpha} and prolyl hydroxylase (PHD2), and a later decrease of vascular endothelial growth factor (VEGF) upon the treatment of Andro. The Andro-inhibited VEGF expression appeared to be a consequence of HIF-1{alpha} inactivation, because its DNA binding activity was suppressed by Andro. Molecular data showed that all these effects of Andro might be mediated via TGF{beta}1/PHD2/HIF-1{alpha} pathway, as demonstrated by the transfection of TGF{beta}1 overexpression vector and PHD2 siRNA, and the usage of a pharmacological MG132 inhibitor. Furthermore, we elucidated the involvement of Andro in HIF-1{alpha} transduced VEGF expression in A549 cells and other NSCLC cell lines. In conclusion, these results highlighted the potential effects of Andro, which may be developed as a chemotherapeutic or an anti-angiogenesis agent for NSCLC in the future.

HIF-1alpha and HIF-2alpha are differentially activated in distinct cell populations in retinal ischaemia.

Directory of Open Access Journals (Sweden)

Freya M Mowat

2010-06-01

Full Text Available Hypoxia plays a key role in ischaemic and neovascular disorders of the retina. Cellular responses to oxygen are mediated by hypoxia-inducible transcription factors (HIFs that are stabilised in hypoxia and induce the expression of a diverse range of genes. The purpose of this study was to define the cellular specificities of HIF-1alpha and HIF-2alpha in retinal ischaemia, and to determine their correlation with the pattern of retinal hypoxia and the expression profiles of induced molecular mediators.We investigated the tissue distribution of retinal hypoxia during oxygen-induced retinopathy (OIR in mice using the bio-reductive drug pimonidazole. We measured the levels of HIF-1alpha and HIF-2alpha proteins by Western blotting and determined their cellular distribution by immunohistochemistry during the development of OIR. We measured the temporal expression profiles of two downstream mediators, vascular endothelial growth factor (VEGF and erythropoietin (Epo by ELISA. Pimonidazole labelling was evident specifically in the inner retina. Labelling peaked at 2 hours after the onset of hypoxia and gradually declined thereafter. Marked binding to Müller glia was evident during the early hypoxic stages of OIR. Both HIF-1alpha and HIF-2alpha protein levels were significantly increased during retinal hypoxia but were evident in distinct cellular distributions; HIF-1alpha stabilisation was evident in neuronal cells throughout the inner retinal layers whereas HIF-2alpha was restricted to Müller glia and astrocytes. Hypoxia and HIF-alpha stabilisation in the retina were closely followed by upregulated expression of the downstream mediators VEGF and EPO.Both HIF-1alpha and HIF-2alpha are activated in close correlation with retinal hypoxia but have contrasting cell specificities, consistent with differential roles in retinal ischaemia. Our findings suggest that HIF-2alpha activation plays a key role in regulating the response of Müller glia to hypoxia.

Lifetime and g-factor measurements of excited states using Coulomb excitation and alpha transfer reactions

Energy Technology Data Exchange (ETDEWEB)

Guevara, Z. E., E-mail: zjguevaram@unal.edu.co; Torres, D. A., E-mail: datorresg@unal.edu.co [Physics Department, Universidad Nacional de Colombia, Bogotá D.C. (Colombia)

2016-07-07

In this contribution the challenges in the use of a setup to simultaneously measure lifetimes and g-factor values will be presented. The simultaneous use of the transient field technique and the Doppler Shift Attenuation Method, to measure magnetic moments and lifetimes respectively, allows to obtain a complete characterization of the currents of nucleons and the deformation in excited states close to the ground state. The technique is at the moment limited to Coulomb excitation and alpha-transfer reactions, what opens an interesting perspective to consider this type of experiments with radioactive beams. The use of deep-inelastic and fusion-evaporation reactions will be discussed. An example of a setup that makes use of a beam of {sup 106}Cd to study excited states of {sup 110}Sn and the beam nuclei itself will be presented.

Enhancement of alpha particles-induced cell transformation by oxygen free radicals and tumor necrosis factor released from phagocytes

International Nuclear Information System (INIS)

Gong Yifen; Guo Renfeng; Zhu Maoxiang; Shou Jiang; Ge Guixiu; Yang Zhihua; Hieber, L.; Peters, K.; Schippel, C.

1997-01-01

To illustrate the role of several endogenous factors released from phagocytes under chronic inflammation in radiation-induced cancer. C 3 T 10 T 1/2 and SHE cells were used as targets, and 238 Pu alpha source was used in alpha irradiation. The enhancement of TF in alpha particles-induced cell transformation by PMA-stimulated human blood and zymosan-stimulated U-937 cells was studied using formation of transformed foci. Transformation frequency (TF) of C 3 H 10 T 1/2 cells exposed to alpha particles of 0.5 Gy increased 2.1 and 2.8 fold by PMA-and PMA-stimulated neutrophils, respectively. TF of irradiated SHE cells at a dose of 0.5 Gy increased 12 fold by the addition of the supernatant of macrophage-like U-937 cell line. It was shown that TF of irradiated SHE cells at above dose increased 8 fold by the supernatant treated with anti-TNF-α could be subcultured continuously in vitro. The cells at 40 th passage and two lines of monoclone cells have the ability to develop malignant tumors in nude mice. The overdose of free radicals and TNF-α released from neutrophils and macrophages have played an important role in low dose radiation-induced cancer

PGC-1alpha is not mandatory for exercise- and training-induced adaptive gene responses in mouse skeletal muscle

DEFF Research Database (Denmark)

Leick, Lotte; Wojtaszewski, Jørgen F P; Johansen, Sune T.

2008-01-01

The aim of the present study was to test the hypothesis that peroxisome proliferator activated receptor-gamma coactivator (PGC) 1alpha is required for exercise-induced adaptive gene responses in skeletal muscle. Whole body PGC-1alpha knockout (KO) and littermate wild-type (WT) mice performed....... Resting muscles of the PGC-1alpha KO mice had lower ( approximately 20%) cytochrome c (cyt c), cytochrome oxidase (COX) I, and aminolevulinate synthase (ALAS) 1 mRNA and protein levels than WT, but similar levels of AMP-activated protein kinase (AMPK) alpha1, AMPKalpha2, and hexokinase (HK) II compared...

Bicyclic Guanidine Catalyzed Asymmetric Tandem Isomerization Intramolecular-Diels-Alder Reaction: The First Catalytic Enantioselective Total Synthesis of (+)-alpha-Yohimbine.

Science.gov (United States)

Feng, Wei; Jiang, Danfeng; Kee, Choon-Wee; Liu, Hongjun; Tan, Choon-Hong

2016-02-04

Hydroisoquinoline derivatives were prepared in moderate to good enantioselectivities via a bicyclic guanidine-catalyzed tandem isomerization intramolecular-Diels-Alder (IMDA) reaction of alkynes. With this synthetic method, the first enantioselective synthesis of (+)-alpha-yohimbine was completed in 9 steps from the IMDA products. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Transition-state structure in the yeast alcohol dehydrogenase reaction: the magnitude of solvent and alpha-secondary hydrogen isotope effects

International Nuclear Information System (INIS)

Welsh, K.M.; Creighton, D.J.; Klinman, J.P.

1980-01-01

Solvent and alpha-secondary isotope effects have been measured in the yeast alcohol dehydrogenase reaction, under conditions of a rate-limiting transfer of hydrogen between coenzyme and substrate. Determination of catalytic constants in H20 and D20 as a function of pH(D) has allowed the separation of solvent effects on pKa from kcat. The small effect of D20 on pKa is tentatively assigned to ionization of an active-site ZnOH 2 . The near absence of an isotope effect on kcat in the direction of alcohol oxidation rules out a mechanism involving concerted catalysis by an active-site base of hydride transfer. The near identity of kinetic and equilibrium alpha-secondary isotope effects in the direction of alcohol oxidation implicates a transition-state structure which resembles aldehyde with regard to bond hybridization properties. The result contrasts sharply with previously reported structure - reactivity correlations, which implicate a transition-state structure resembling alcohol with regard to charge properties. The significance of these findings to the mechanism of NAD(P)H-dependent redox reactions is discussed

Tumor necrosis factor-alpha-independent downregulation of hepatic cholesterol 7alpha-hydroxylase gene in mice treated with lead nitrate.

Science.gov (United States)

Kojima, Misaki; Sekikawa, Kenji; Nemoto, Kiyomitsu; Degawa, Masakuni

2005-10-01

We previously reported that lead nitrate (LN), an inducer of hepatic tumor necrosis factor-alpha (TNF-alpha), downregulated gene expression of cholesterol 7alpha-hydroxylase. Herein, to clarify the role of TNF-alpha in LN-induced downregulation of cholesterol 7alpha-hydroxylase, effects of LN on gene expression of hepatic cholesterol 7alpha-hydroxylase (Cyp7a1) in TNF-alpha-knockout (KO) and TNF-alpha-wild-type (WT) mice were comparatively examined. Gene expression of hepatic Cyp7a1 in both WT and KO mice decreased to less than 5% of the corresponding controls at 6-12 h after treatment with LN (100 mumol/kg body weight, iv). Levels of hepatic TNF-alpha protein in either WT or KO mice were below the detection limit, although expression levels of the TNF-alpha gene markedly increased at 6 h in WT mice by LN treatment, but not in KO mice. In contrast, in both WT and KO mice, levels of hepatic IL-1beta protein, which is known to be a suppressor of the cholesterol 7alpha-hydroxylase gene in hamsters, were significantly increased 3-6 h after LN treatment. Furthermore, LN-induced downregulation of the Cyp7a1 gene did not necessarily result from altered gene expression of hepatic transcription factors, including positive regulators (liver X receptor alpha, retinoid X receptor alpha, fetoprotein transcription factor, and hepatocyte nuclear factor 4alpha) and a negative regulator small heterodimer partner responsible for expression of the Cyp7a1 gene. The present findings indicated that LN-induced downregulation of the Cyp7a1 gene in mice did not necessarily occur through a TNF-alpha-dependent pathway and might occur mainly through an IL-1beta-dependent pathway.

Surface chemical reactions induced by molecules electronically-excited in the gas

DEFF Research Database (Denmark)

Petrunin, Victor V.

2011-01-01

and alignment are taking place, guiding all the molecules towards the intersections with the ground state PES, where transitions to the ground state PES will occur with minimum energy dissipation. The accumulated kinetic energy may be used to overcome the chemical reaction barrier. While recombination chemical...... be readily produced. Products of chemical adsorption and/or chemical reactions induced within adsorbates are aggregated on the surface and observed by light scattering. We will demonstrate how pressure and spectral dependencies of the chemical outcomes, polarization of the light and interference of two laser...... beams inducing the reaction can be used to distinguish the new process we try to investigate from chemical reactions induced by photoexcitation within adsorbed molecules and/or gas phase photolysis....

Contribution to the study of nuclear reaction analysis with low energy alpha particles (<=3,5 MeV). Comparative study of Ag non destructive nuclear reaction determination in numismatology

International Nuclear Information System (INIS)

Basutcu, Mehmet.

1980-12-01

The first part of this work concerns the development of the new analytical possibilities offered by gamma spectrometry with a beam of low energy alpha particles. With this method twenty five elements can be analyzed by non-destructive methods. Special attention is given to the determination of light elements such as lithium, boron, fluorine and sodium. The reactions brought about by the low energy alpha particles on light elements are (α,n), (α,p) or (α,α') type reactions. The various applications developed are presented after the description of the experimental conditions and the method used for calculating the contents. The problems related to the calibration, accuracy and exactness of the determinations are also discussed. The second part is about the contribution of nuclear analysis methods and of X-ray fluorescence in the field of numismatic research. Attention is focused solely on the determination of the major ingredients of coins, silver in particular. The results provided by proton activation, neutron activation in a flux of 'thermalized' neutrons of a 252 Cf isotopic source on the one hand, and by the fast neutrons of the cyclotron on the other, by gamma spectrometry under a beam of protons and alpha particles and by X-ray fluorescence are thus compared for the same analytical problem in order to grasp in a better manner the specificity of each method and to bring into evidence the complementarity they present [fr

Anticytokine treatment of established type II collagen-induced arthritis in DBA/1 mice: a comparative study using anti-TNFalpha, anti-IL-1alpha/beta and IL-1Ra.

NARCIS (Netherlands)

Joosten, L.A.B.; Helsen, M.M.A.; Loo, F.A.J. van de; Berg, W.B. van den

2008-01-01

OBJECTIVE: To examine the role of tumor necrosis factor alpha (TNF alpha), interleukin-1 alpha (IL-1 alpha), and IL-1 beta in collagen-induced arthritis (CIA), immediately after onset and during the phase of established arthritis. METHODS: Male DBA/1 mice with collagen-induced arthritis were treated

Pion-induced knock-out reactions

International Nuclear Information System (INIS)

Jain, B.K.; Phatak, S.C.

1977-01-01

A strong absorption model for pion-induced Knock-out reactions is proposed. The distortion of the in-coming and out-going pions has been included by (1) computing pion wave number in nuclear medium (dispersive effect) and (2) excluding the central region of the nucleus where the real pion-absorption is dominant (absorption effect). In order to study the dependence of the (π + π + p) reaction on the off-shell pion-nucleon t-matrix, different off-shell extrapolations are used. The magnitude of the cross-sections seems to be sensitive to the type of off-shell extrapolation; their shapes, however, are similar. The theoretical results are compared with experimental data. The agreement between the theoretical results for separable off-shell extrapolation and the data is good. (author)

Electro-induced reactions of biologically important molecules

International Nuclear Information System (INIS)

Kocisek, J.

2010-01-01

The thesis presents the results of research activities in the field of electron interactions with biologically relevant molecules which was carried out during my PhD studies at the Department of Experimental Physics, Comenius University in Bratislava. Electron induced interactions with biologically relevant molecules were experimentally studied using crossed electron-molecule beams experiment. The obtained results, were presented in four publications in international scientific journals. First study of deals with electron impact ionisation of furanose alcohols [see 1. in list of author publications on page 22]. It has been motivated by most important works in the field of electron induced damages of DNA bases [4]. Studied 3-hydroxytetrahydrofuran and tetrahydrofurfuryl alcohol, are important model molecules for more complex biological systems (e.g. deoxyribose).The influence of hydroxyl group on stabilisation of the positive ions of the molecules, together with the stability of furan ring in ionized form are main themes of the study. The studies of small amides and aminoacids are connected to scientific studies in the field of formation of the aminoacids and other biologically relevant molecules in space and works trying to explain electron induced processes in more complex molecules[12, 13, 24]. The most important results were obtained for aminoacid Serine [see 2. in list of author publications on page 22]. We have showed that additional OH group of Serine considerably lower the reaction enthalpy limit of reactions resulting to formation of neutral water molecules, in comparison to other amino acids. Also the study of (M-H)- reaction channel using the electron beam with FWHM under 100 meV is of high importance in the field. The last part of the thesis is focused on the electron interactions with organosilane compounds. Materials prepared from organosilane molecules in plasmas have wide range of applications in both biology and medicine. We have studied electron

{sup 17}O({alpha},{gamma}){sup 21}Ne and {sup 17}O({alpha},n){sup 20}Ne for the weak s process

Energy Technology Data Exchange (ETDEWEB)

Best, A.; Goerres, J.; Beard, M.; Couder, M.; Boer, R. de; Falahat, S.; Gueray, R. T.; Kontos, A.; Kratz, K.-L.; LeBlanc, P. J.; Li, Q.; O' Brien, S.; Oezkan, N.; Pignatari, M.; Sonnabend, K.; Talwar, R.; Tan, W.; Uberseder, E.; Wiescher, M. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States) and Department for Biogeochemistry, Max-Planck-Institute for Chemistry, 55020 Mainz (Germany); Department of Physics, Kacaeli University, Umuttepe 41380, Kocaeli (Turkey); Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Department for Biogeochemistry, Max-Planck-Institute for Chemistry, 55020 Mainz (Germany); Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Department of Physics, Kacaeli University, Umuttepe 41380, Kocaeli (Turkey); Department of Physics, University of Basel, Basel 4056 (Switzerland); Institute for Applied Physics, Goethe-University Frankfurt, 60325 Frankfurt (Germany); Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States)

2012-11-20

The ratio of the reaction rates of the competing channels {sup 17}O({alpha}{gamma}){sup 21}Ne and {sup 17}O({alpha},n){sup 20}Ne determines the efficiency of {sup 16}O as a neutron poison in the s process in low metallicity rotating stars. It has a large impact on the element production, either producing elements to the mass range of A=90 in case of a significant poisoning effect or extending the mass range up to the region of A=150 if the {gamma} channel is of negligible strength. We present an improved study of the reaction {sup 17}O({alpha},n){sup 20}Ne, including an independent measurement of the {sup 17}O({alpha},n{sub 1}){sup 20}Ne channel. A simultaneous R-Matrix fit to both the n{sub 0} and the n{sub 1} channels has been performed. New reaction rates, including recent data on the {sup 17}O({alpha},{gamma}){sup 21}Ne reaction, have been calculated and used as input for stellar network calculations and their impact on the s process in rotating massive stars is discussed.

Angular distributions of the alpha particle production in the 7Li+144Sm system at near-barrier energies

International Nuclear Information System (INIS)

Carnelli, P F F; Arazi, A; Capurro, O A; Niello, J O Fernández; Heimann, D Martinez; Pacheco, A J; Cardona, M A; De Barbará, E; Figueira, J M; Hojman, D L; Martí, G V; Negri, A E

2015-01-01

We have studied the production of alpha particles in reactions induced by 7 Li projectiles on a 144 Sm target at bombarding energies of 18, 24 and 30 MeV over the 15°-140° angular range. The purpose of the investigation has been to determine the contribution of different mechanisms in reactions that involve weakly bound projectiles. We have included in our analysis several processes that can either directly or sequentially lead to the emission of alpha particles: complete fusion, direct transfer of 3 H, capture breakup (incomplete fusion, sequential complete fusion) and non-capture breakup. In order to distinguish alpha particles stemming from these processes it is necessary to determine the mass and charge of the reaction products and to obtain precise measurements of their energies and scattering angles over relatively wide ranges of these variables. We have done this using a detection system consisting of an ionization chamber plus three position sensitive detectors. We present results of these measurements and a preliminary interpretation based on kinematical considerations and comparisons with predictions from a statistical model. (paper)

On light cluster production in nucleon induced reactions at intermediate energy

Energy Technology Data Exchange (ETDEWEB)

Lacroix, D.; Blideanu, V.; Durand, D

2004-09-01

A dynamical model dedicated to nucleon induced reaction between 30-150 MeV is presented. It considers different stages of the reaction: the approaching phase, the in-medium nucleon-nucleon collisions, the cluster formation and the secondary de-excitation process. The notions of influence area and phase-space exploration during the reaction are introduced. The importance of the geometry of the reaction and of the conservation laws are underlined. The model is able to globally reproduce the absolute cross sections for the emission of neutron and light charged particles for proton and neutron induced reactions on heavy and intermediate mass targets ({sup 56}Fe and {sup 208}Pb). (authors)

On light cluster production in nucleon induced reactions at intermediate energy

International Nuclear Information System (INIS)

Lacroix, D.; Blideanu, V.; Durand, D.

2004-09-01

A dynamical model dedicated to nucleon induced reaction between 30-150 MeV is presented. It considers different stages of the reaction: the approaching phase, the in-medium nucleon-nucleon collisions, the cluster formation and the secondary de-excitation process. The notions of influence area and phase-space exploration during the reaction are introduced. The importance of the geometry of the reaction and of the conservation laws are underlined. The model is able to globally reproduce the absolute cross sections for the emission of neutron and light charged particles for proton and neutron induced reactions on heavy and intermediate mass targets ( 56 Fe and 208 Pb). (authors)

The effect of individual upper alpha band enhancing neurofeedbac kon reaction-time as an indicator of short-term memory in women employee’s

Directory of Open Access Journals (Sweden)

Mersedeh Jahanseir

2014-11-01

Full Text Available Background: In neurofeedback systems, people are able to reinforce or hinder their basic EEG rhythms according to operant conditioninin recent studies the effect of neurofeedback training on improvement of working memory has been shown on the healthy subjects. Disadvantage of neurofeedback is the high number of training sessions and high cost. In previous studies, alpha band power within (8-12 Hz has been considered for all subjects. Previous research reached the conclusion that by using individual upper alpha in neurofeedback, learning rate will increase, so the training sessions and the cost of training will be reduced. Material and Methods: In this study, all participants were female, 10 adults (10 women, mean age 33.8 years, SD=3.56 years. Randomly assigned to control and test group, five in test group and five in control group. Each subject performed the memory test four times, two times before the start of the first neurofeedback training and two times after the end of the last neurofeedback session. Eight training sessions were held, each session had three trials. Results: Discriminate response to the color of the drawing, as well as reaction time hadsignificant effects for test group (p0.05. Before and after eight training sessions by individual upper alpha power neurofeedback, reaction time of discriminate response to the color of the drawing for test group decreased and had significant effects (p0.05. Conclusion: Increasing relative individual upper alpha power, caused by neurofeedback training during eight sessions, indicated that this method increases the memory of women employees, and improves the ability of discriminative response to the color (red & green of the drawing as well as reducing reaction time.

Enhanced actions of insulin-like growth factor-I and interferon-alpha co-administration in experimental cirrhosis.

Science.gov (United States)

Tutau, Federico; Rodríguez-Ortigosa, Carlos; Puche, Juan Enrique; Juanarena, Nerea; Monreal, Iñigo; García Fernández, María; Clavijo, Encarna; Castilla, Alberto; Castilla-Cortázar, Inma

2009-01-01

Cirrhosis is a diffuse process of hepatic fibrosis and regenerative nodule formation. The liver is the major source of circulating insulin-like growth factor-I (IGF-I) whose plasma levels are diminished in cirrhosis. IGF-I supplementation has been shown to induce beneficial effects in cirrhosis, including antifibrogenic and hepatoprotective effects. On other hand, interferon-alpha (IFN-alpha) therapy seems to suppress the progression of hepatic fibrosis. The aim of this study was to investigate the effect of the co-administration of IGF-I+IFN-alpha to Wistar rats with CCl(4)-induced cirrhosis, exploring liver function tests, hepatic lipid peroxidation and histopathology. The mechanisms underlying the effects of these agents were studied by reverse transcription-polymerase chain reaction, determining the expression of some factors [hepatocyte growth factor (HGF), transforming growth factor-beta (TGF-beta), alpha-smooth muscle actin, collagen, tissular inhibitor of metalloproteinases-1 and pregnane X receptor (PXR)] involved in fibrogenesis, fibrolysis and/or hepatoprotection. Both IGF-I and IFN-alpha exerted significant effects on fibrogenesis. IGF-I significantly increased serum albumin and HGF whereas IFN-alpha-therapy did not. The inhibition of TGF-beta expression was only observed by the effect of IFN-alpha-therapy. In addition, only the co-administration of IGF-I and IFN-alpha was able to increase the PXR. The combined therapy with both factors improved liver function tests, hepatic lipid peroxidation and reduced fibrosis, inducing a relevant histological improvement, reducing fibrosis and recovering hepatic architecture. The co-administration IGF-I+IFN enhanced all the beneficial effects observed with each factor separately, showing an additive action on histopathology and PXR expression, which is involved in the inhibition of fibrogenesis.

Efficient one-pot enzymatic synthesis of alpha-(1 -> 4)-glucosidic disaccharides through a coupled reaction catalysed by Lactobacillus acidophilus NCFM maltose phosphorylase

DEFF Research Database (Denmark)

Nakai, Hiroyuki; Dilokpimol, Adiphol; Abou Hachem, Maher

2010-01-01

Lactobacillus acidophilus NCFM maltose phosphorylase (LaMalP) of glycoside hydrolase family 65 catalysed enzymatic synthesis of alpha-(1 -> 4)-glucostdic disacchandes from maltose and five monosacchandes in a coupled phosphorolysis/reverse phosphorolysis one-pot reaction Thus phosphorolysis...

High sensitivity boron quantification in bulk silicon using the {sup 11}B(p,{alpha}{sub 0}){sup 8}Be nuclear reaction

Energy Technology Data Exchange (ETDEWEB)

Moro, Marcos V.; Silva, Tiago F. da; Added, Nemitala; Rizutto, Marcia A.; Tabacniks, Manfredo H. [Instituto de Fisica da Universidade de Sao Paulo, C.P. 66318, 05315-970 Sao Paulo, SP (Brazil); Neira, John B.; Neto, Joao B. F. [Institute of Research Tecnology, Cidade Universitaria, SP, 05508-091 (Brazil)

2013-05-06

There is a great need to quantify sub-ppm levels of boron in bulk silicon. There are several methods to analyze B in Si: Nuclear Reaction Analysis using the {sup 11}B(p,{alpha}{sub 0}){sup 8}Be reaction exhibits a quantification limit of some hundreds ppm of B in Si. Heavy Ion Elastic Recoil Detection Analysis offers a detection limit of 5 to 10 at. ppm. Secondary Ion Mass Spectrometry is the method of choice of the semiconductor industry for the analysis of B in Si. This work verifies the use of NRA to quantify B in Si, and the corresponding detection limits. Proton beam with 1.6 up to 2.6 MeV was used to obtain the cross-section of the {sup 11}B(p,{alpha}{sub 0}){sup 8}Be nuclear reaction at 170 Degree-Sign scattering angle. The results show good agreementwith literature indicating that the quantification of boron in silicon can be achieved at 100 ppm level (high sensitivity) at LAMFI-IFUSP with about 16% uncertainty. Increasing the detection solid angle and the collected beam charge, can reduce the detection limit to less than 100 ppm meeting present technological needs.

Synthetic. cap alpha. subunit peptide 125-147 of human nicotinic acetylcholine receptor induces antibodies to native receptor

Energy Technology Data Exchange (ETDEWEB)

McCormick, D.J.; Griesmann, G.E.; Huang, Z.; Lennon, V.A.

1986-03-05

A synthetic peptide corresponding to residues 125-147 of the Torpedo acetylcholine receptor (AChR) ..cap alpha.. subunit proved to be a major antigenic region of the AChR. Rats inoculated with 50 ..mu..g of peptide (T ..cap alpha.. 125-147) developed T cell immunity and antibodies to native AChR and signs of experimental autoimmune myasthenia gravis. They report the synthesis and preliminary testing of a disulfide-looped peptide comprising residues 125-147 of the human AChR ..cap alpha.. subunit. Peptide H ..cap alpha.. 125-147 differs from T ..cap alpha.. 125-147 at residues 139 (Glu for Gln) and 143 (Ser for Thr). In immunoprecipitation assays, antibodies to Torpedo AChR bound /sup 125/I-labelled H..cap alpha.. 125-147 antibody bound H..cap alpha.. 125-147, but monoclonal antibodies to an immunodominant region of native AChR bound neither H..cap alpha.. 125-147 nor T ..cap alpha.. 125-147. Rats immunized with H ..cap alpha.. 125-147 produced anti-mammalian muscle AChR antibodies that induced modulation of AChRs from cultured human myotubes. Thus, region 125-147 of the human AChR ..cap alpha.. subunit is extracellular in muscle, and is both antigenic and immunogenic. It remains to be determined whether or not autoantibodies to this region may in part cause the weakness or myasthenia gravis in man.

Investigation of the influence of incomplete fusion on complete fusion of {sup 12}C-induced reactions at {approx} 4-7.2 MeV/nucleon

Energy Technology Data Exchange (ETDEWEB)

Amanuel, F.K. [INFN, Laboratori Nazionali di Legnaro, Legnaro (Padova) (Italy); Zelalem, B.; Chaubey, A.K. [Addis Ababa University, Department of Physics, P.O.Box 1176, Addis Ababa (Ethiopia); Agarwal, Avinash [Bareilly College, Department of Physics, Bareilly (India); Rizvi, I.A.; Maheshwari, Anjana; Ahmed, Tauseef [Aligarh Muslim University, Department of Physics, Aligarh (India)

2011-12-15

In this paper, we present the results of our investigation of reaction dynamics leading to incomplete fusion of heavy ions at moderate excitation energies, especially the influence of incomplete fusion on complete fusion of {sup 12}C -induced reactions at specific energies {approx} 4-7.2M eV/nucleon. Excitation functions of various reaction products populated via complete and/or incomplete fusions of a {sup 12}C projectile with {sup 93}Nb, {sup 59}Co and {sup 52}Cr targets were measured at several specific energies {approx} 4-7.2 MeV/nucleon, using a recoil catcher technique, followed by off-line {gamma}-ray spectrometry. The measured excitation functions were compared with theoretical values obtained using the PACE4 statistical model code. For representative non-{alpha}-emitting channels in the {sup 12}C + {sup 93}Nb system, the experimentally measured excitation functions were, in general, found to be in good agreement with the theoretical predictions. However, for {alpha}-emitting channels in the {sup 12}C + {sup 93}Nb, {sup 12}C + {sup 59}Co, and {sup 12}C + {sup 52}Cr systems, the measured excitation functions were higher than the predictions of the theoretical model code, which may be credited to incomplete fusion reactions at these energies. An attempt was made to estimate the incomplete fusion fraction for the present systems, which revealed that the fraction was sensitive to the projectile energy and mass asymmetry of the entrance channel. (orig.)

Investigations of nuclear structure and nuclear reactions induced by complex projectiles

International Nuclear Information System (INIS)

Sarantites, D.G.

1993-01-01

This is a progress report on activities of the Washington University group in nuclear reaction studies for the period Sept 1, 1992 to Aug 31, 1993. This group has a research program which touches five areas of nuclear physics: nuclear structure studies at high spin; studies at the interface between structure and reactions; production and study of hot nuclei; reaction mechanism studies; development and use of novel techniques and instrumentation in the above areas of research. Specific activities of the group include in part: superdeformation in 82 Sr; structure of and identical bands in 182 Hg and 178 Pt; a highly deformed band in 136 Pm; particle decay of the 164 Yb compound nucleus; fusion reactions; proton evaporation; two-proton decay of 12 O; modeling and theoretical studies; excited 16 O disassembly into four alpha particles; 209 Bi + 136 Xe collisions at 28.2 MeV/amu; and development work on 4π solid angle gamma detectors, and x-ray detectors

Statins and PPAR{alpha} agonists induce myotoxicity in differentiated rat skeletal muscle cultures but do not exhibit synergy with co-treatment

Energy Technology Data Exchange (ETDEWEB)

Johnson, Timothy E [Department of Safety Assessment, Merck Research Laboratories, WP45-319, Merck Research Laboratories, West Point, PA 19486 (United States); Zhang, Xiaohua [Department of Biometrics Research, Merck Research Laboratories, West Point, PA 19486 (United States); Shi, Shu [Department of Safety Assessment, Merck Research Laboratories, WP45-319, Merck Research Laboratories, West Point, PA 19486 (United States); Umbenhauer, Diane R [Department of Safety Assessment, Merck Research Laboratories, WP45-319, Merck Research Laboratories, West Point, PA 19486 (United States)

2005-11-01

Statins and fibrates (weak PPAR{alpha} agonists) are prescribed for the treatment of lipid disorders. Both drugs cause myopathy, but with a low incidence, 0.1-0.5%. However, combined statin and fibrate therapy can enhance myopathy risk. We tested the myotoxic potential of PPAR subtype selective agonists alone and in combination with statins in a differentiated rat myotube model. A pharmacologically potent experimental PPAR{alpha} agonist, Compound A, induced myotoxicity as assessed by TUNEL staining at a minimum concentration of 1 nM, while other weaker PPAR{alpha} compounds, for example, WY-14643, Gemfibrozil and Bezafibrate increased the percentage of TUNEL-positive nuclei at micromolar concentrations. In contrast, the PPAR{gamma} agonist Rosiglitazone caused little or no cell death at up to 10 {mu}M and the PPAR{delta} ligand GW-501516 exhibited comparatively less myotoxicity than that seen with Compound A. An experimental statin (Compound B) and Atorvastatin also increased the percentage of TUNEL-positive nuclei and co-treatment with WY-14643, Gemfibrozil or Bezafibrate had less than a full additive effect on statin-induced cell killing. The mechanism of PPAR{alpha} agonist-induced cell death was different from that of statins. Unlike statins, Compound A and WY-14643 did not activate caspase 3/7. In addition, mevalonate and geranylgeraniol reversed the toxicity caused by statins, but did not prevent the cell killing induced by WY-14643. Furthermore, unlike statins, Compound A did not inhibit the isoprenylation of rab4 or rap1a. Interestingly, Compound A and Compound B had differential effects on ATP levels. Taken together, these observations support the hypothesis that in rat myotube cultures, PPAR{alpha} agonism mediates in part the toxicity response to PPAR{alpha} compounds. Furthermore, PPAR{alpha} agonists and statins cause myotoxicity through distinct and independent pathways.

Two-stream cyclotron radiative instabilities due to the marginally mirror-trapped fraction for fustion alphas in tokamaks

International Nuclear Information System (INIS)

Arunasalam, V.

1995-07-01

It is shown here that the marginally mirror-trapped fraction of the newly-born fusion alpha particles in the deuterium-tritium (DT) reaction dominated tokamak plasmas can induce a two-stream cyclotron radiative instability for the fast Alfven waves propagating near the harmonics of the alpha particle cyclotron frequency ω cα . This can explain both the experimentally observed time behavior and the spatially localized origin of the fusion product ion cyclotron emission (ICE) in TFTR at frequencies ω ∼ mω cα

Radiation induced structural changes in alpha-copper-zinc alloys

International Nuclear Information System (INIS)

Schuele, W.; Gieb, M.

1991-01-01

During irradiation of alpha-copper-zinc alloys with high energy electrons and protons a decrease of the electrical resistivity due to an increase of the degree of short range order is observed through radiation enhanced diffusion followed by an increase of the electrical resistivity through the formation of radiation induced interstitial clusters. The initial formation rate of interstitial clusters increases about linearly with the displacement rate for electron and proton irradiation. The largest initial formation rate is found between 60 and 130 0 C becoming negligibly small above 158 0 C and decreases drastically below 60 0 C. The dynamic steady state interstitial cluster concentration increases with decreasing irradiation temperature in the investigated temperature range between 158 and 40 0 C. Above 158 0 C the formation rate of interstitial clusters is negligibly small. Thus the transition temperature for radiation induced interstitial cluster formation is 158 0 C, depending mainly on the migration activation energy of vacancies. The radiation induced interstitial clusters are precipitates in those alloys in which the diffusion rate of the undersized component atoms via an interstitialcy diffusion mechanism is larger than that of the other atoms

Experimentally nonylphenol-polluted diet induces the expression of silent genes VTG and ER{alpha} in the liver of male lizard Podarcis sicula

Energy Technology Data Exchange (ETDEWEB)

Verderame, Mariailaria; Prisco, Marina; Andreuccetti, Piero [Department of Biological Sciences, Evolutionary and Comparative Biology Division, University Federico II of Naples, Via Mezzocannone 8, 80134 Naples (Italy); Aniello, Francesco [Department of Biological Sciences, Genetic and Molecular Biology Division, University Federico II of Naples, Via Mezzocannone 8, 80134 Naples (Italy); Limatola, Ermelinda, E-mail: limatola@unina.it [Department of Biological Sciences, Evolutionary and Comparative Biology Division, University Federico II of Naples, Via Mezzocannone 8, 80134 Naples (Italy)

2011-05-15

Endocrine Disruptor Chemicals (EDCs) with estrogen-like properties i.e nonylphenol (NP) induce vitellogenin (VTG) synthesis in males of aquatic and semi-aquatic specie. In the oviparous species VTG is a female-specific oestrogen dependent protein. Males are unable to synthesize VTG except after E{sub 2} treatment. This study aimed to verify if NP, administered via food and water, is able to induce the expression of VTG even in males of vertebrates with a terrestrial habitat such as the lizard Podarcis. By means of ICC, ISH, W/B and ELISA we demonstrated that NP induces the presence of VTG in the plasma and its expression in the liver. VTG, undetectable in untreated males, reaches the value of 4.34 {mu}g/{mu}l in the experimental ones. Expression analysis and ISH in the liver showed that an NP-polluted diet also elicits the expression of ER{alpha} in the liver which is known to be related to VTG synthesis in Podarcis. - Highlights: > Nonylphenol (NP) polluted diet induces VTG synthesis in a terrestrial vertebrate. > VTG and ER{alpha} genes are unexpressed in the liver of untreated male lizards Podarcis. > In the liver cells of NP-treated males the expression of both VTG and ER{alpha} occurs. > In treated males VTG synthesis is coupled with ER{alpha} expression as in breeding females. - NP-polluted diet induces the expression of ER{alpha} and VTG in the liver.

RhoA/ROCK Signaling Pathway Mediates Shuanghuanglian Injection-Induced Pseudo-allergic Reactions.

Science.gov (United States)

Han, Jiayin; Zhao, Yong; Zhang, Yushi; Li, Chunying; Yi, Yan; Pan, Chen; Tian, Jingzhuo; Yang, Yifei; Cui, Hongyu; Wang, Lianmei; Liu, Suyan; Liu, Jing; Deng, Nuo; Liang, Aihua

2018-01-01

Background: Shuanghuanglian injection (SHLI) is a famous Chinese medicine used as an intravenous preparation for the treatment of acute respiratory tract infections. In the recent years, the immediate hypersensitivity reactions induced by SHLI have attracted broad attention. However, the mechanism involved in these reactions has not yet been elucidated. The present study aims to explore the characteristics of the immediate hypersensitivity reactions induced by SHLI and deciphers the role of the RhoA/ROCK signaling pathway in these reactions. Methods: SHLI-immunized mice or naive mice were intravenously injected (i.v.) with SHLI (600 mg/kg) once, and vascular leakage in the ears was evaluated. Passive cutaneous anaphylaxis test was conducted using sera collected from SHLI-immunized mice. Naive mice were administered (i.v.) with a single dose of 150, 300, or 600 mg/kg of SHLI, and vascular leakage, histamine release, and histopathological alterations in the ears, lungs, and intestines were tested. In vitro , human umbilical vein endothelial cell (HUVEC) monolayer was incubated with SHLI (0.05, 0.1, or 0.15 mg/mL), and the changes in endothelial permeability and cytoskeleton were observed. Western blot analysis was performed and ROCK inhibitor was employed to investigate the contribution of the RhoA/ROCK signaling pathway in SHLI-induced hypersensitivity reactions, both in HUVECs and in mice. Results: Our results indicate that SHLI was able to cause immediate dose-dependent vascular leakage, edema, and exudates in the ears, lungs, and intestines, and histamine release in mice. These were pseudo-allergic reactions, as SHLI-specific IgE was not elicited during sensitization. In addition, SHLI induced reorganization of actin cytoskeleton and disrupted the endothelial barrier. The administration of SHLI directly activated the RhoA/ROCK signaling pathway both in HUVECs and in the ears, lungs, and intestines of mice. Fasudil hydrochloride, a ROCK inhibitor, ameliorated the

Monte Carlo simulation of the alpha-amylolysis of amylopectin potato starch. 2. alpha-amylolysis of amylopectin

NARCIS (Netherlands)

Marchal, L.M.; Ulijn, R.V.; Gooijer, de C.D.; Franke, G.T.; Tramper, J.

2003-01-01

A model is presented that describes all the saccharides that are produced during the hydrolysis of starch by an alpha-amylase. Potato amylopectin, the substrate of the hydrolysis reaction, was modeled in a computer matrix. The four different subsite maps presented in literature for alpha-amylase

Beta3 subunits promote expression and nicotine-induced up-regulation of human nicotinic alpha6* nicotinic acetylcholine receptors expressed in transfected cell lines.

Science.gov (United States)

Tumkosit, Prem; Kuryatov, Alexander; Luo, Jie; Lindstrom, Jon

2006-10-01

Nicotinic acetylcholine receptors (AChRs) containing alpha6 subunits are typically found at aminergic nerve endings where they play important roles in nicotine addiction and Parkinson's disease. alpha6* AChRs usually contain beta3 subunits. beta3 subunits are presumed to assemble only in the accessory subunit position within AChRs where they do not participate in forming acetylcholine binding sites. Assembly of subunits in the accessory position may be a critical final step in assembly of mature AChRs. Human alpha6 AChRs subtypes were permanently transfected into human tsA201 human embryonic kidney (HEK) cell lines. alpha6beta2beta3 and alpha6beta4beta3 cell lines were found to express much larger amounts of AChRs and were more sensitive to nicotine-induced increase in the amount of AChRs than were alpha6beta2 or alpha6beta4 cell lines. The increased sensitivity to nicotine-induced up-regulation was due not to a beta3-induced increase in affinity for nicotine but probably to a direct effect on assembly of AChR subunits. HEK cells express only a small amount of mature alpha6beta2 AChRs, but many of these subunits are on the cell surface. This contrasts with Xenopus laevis oocytes, which express a large amount of incorrectly assembled alpha6beta2 subunits that bind cholinergic ligands but form large amorphous intracellular aggregates. Monoclonal antibodies (mAbs) were made to the alpha6 and beta3 subunits to aid in the characterization of these AChRs. The alpha6 mAbs bind to epitopes C-terminal of the extracellular domain. These data demonstrate that both cell type and the accessory subunit beta3 can play important roles in alpha6* AChR expression, stability, and up-regulation by nicotine.

Small interfering RNA targeting HIF-1{alpha} reduces hypoxia-dependent transcription and radiosensitizes hypoxic HT 1080 human fibrosarcoma cells in vitro

Energy Technology Data Exchange (ETDEWEB)

Staab, Adrian [Wuerzburg Univ. (Germany). Dept. of Radiation Oncology; Paul Scherrer Institute (PSI), Villigen (Switzerland); Fleischer, Markus [Wuerzburg Univ. (Germany). Dept. of Radiation Oncology; Wuerzburg Univ. (Germany). Medical Clinic II; Loeffler, Juergen; Einsele, Herrmann [Wuerzburg Univ. (Germany). Medical Clinic II; Said, Harun M.; Katzer, Astrid; Flentje, Michael [Wuerzburg Univ. (Germany). Dept. of Radiation Oncology; Plathow, Christian [Freiburg Univ. (Germany). Dept. of Nuclear Medicine; Vordermark, Dirk [Wuerzburg Univ. (Germany). Dept. of Radiation Oncology; Halle-Wittenberg Univ. (Germany). Dept. of Radiation Oncology

2011-04-15

Background: Hypoxia inducible factor-1 has been identified as a potential target to overcome hypoxia-induced radioresistance The aim of the present study was to investigate whether selective HIF-1 inhibition via small interfering RNA (siRNA) targeting hypoxia-inducible factor 1{alpha} (HIF-1{alpha}) affects hypoxia-induced radioresistance in HT 1080 human fibrosarcoma cells. Material and Methods: HIF-1{alpha} expression in HT 1080 human fibrosarcoma cells in vitro was silenced using HIF-1{alpha} siRNA sequence primers. Quantitative real-time polymerase chain reaction assay was performed to quantify the mRNA expression of HIF-1{alpha}. HIF-1{alpha} protein levels were studied by Western blotting at 20% (air) or after 12 hours at 0.1% O{sub 2} (hypoxia). Cells were assayed for clonogenic survival after irradiation with 2, 5, or 10 Gy, under normoxic or hypoxic conditions in the presence of HIF-1{alpha}-targeted or control siRNA sequences. A modified oxygen enhancement ratio (OER') was calculated as the ratio of the doses to achieve the same survival at 0.1% O{sub 2} as at ambient oxygen tensions. OER' was obtained at cell survival levels of 50%, 37%, and 10%. Results: HIF-1{alpha}-targeted siRNA enhanced radiation treatment efficacy under severely hypoxic conditions compared to tumor cells treated with scrambled control siRNA. OER was reduced on all survival levels after treatment with HIF-1{alpha}-targeted siRNA, suggesting that inhibition of HIF-1 activation by using HIF-1{alpha}-targeted siRNA increases radiosensitivity of hypoxic tumor cells in vitro. Conclusion: Inhibition of HIF-1 activation by using HIF-1{alpha}-targeted siRNA clearly acts synergistically with radiotherapy and increase radiosensitivity of hypoxic cells in vitro. (orig.)

The CCONE Code System and its Application to Nuclear Data Evaluation for Fission and Other Reactions

Science.gov (United States)

Iwamoto, O.; Iwamoto, N.; Kunieda, S.; Minato, F.; Shibata, K.

2016-01-01

A computer code system, CCONE, was developed for nuclear data evaluation within the JENDL project. The CCONE code system integrates various nuclear reaction models needed to describe nucleon, light charged nuclei up to alpha-particle and photon induced reactions. The code is written in the C++ programming language using an object-oriented technology. At first, it was applied to neutron-induced reaction data on actinides, which were compiled into JENDL Actinide File 2008 and JENDL-4.0. It has been extensively used in various nuclear data evaluations for both actinide and non-actinide nuclei. The CCONE code has been upgraded to nuclear data evaluation at higher incident energies for neutron-, proton-, and photon-induced reactions. It was also used for estimating β-delayed neutron emission. This paper describes the CCONE code system indicating the concept and design of coding and inputs. Details of the formulation for modelings of the direct, pre-equilibrium and compound reactions are presented. Applications to the nuclear data evaluations such as neutron-induced reactions on actinides and medium-heavy nuclei, high-energy nucleon-induced reactions, photonuclear reaction and β-delayed neutron emission are mentioned.

The CCONE Code System and its Application to Nuclear Data Evaluation for Fission and Other Reactions

Energy Technology Data Exchange (ETDEWEB)

Iwamoto, O., E-mail: iwamoto.osamu@jaea.go.jp; Iwamoto, N.; Kunieda, S.; Minato, F.; Shibata, K.

2016-01-15

A computer code system, CCONE, was developed for nuclear data evaluation within the JENDL project. The CCONE code system integrates various nuclear reaction models needed to describe nucleon, light charged nuclei up to alpha-particle and photon induced reactions. The code is written in the C++ programming language using an object-oriented technology. At first, it was applied to neutron-induced reaction data on actinides, which were compiled into JENDL Actinide File 2008 and JENDL-4.0. It has been extensively used in various nuclear data evaluations for both actinide and non-actinide nuclei. The CCONE code has been upgraded to nuclear data evaluation at higher incident energies for neutron-, proton-, and photon-induced reactions. It was also used for estimating β-delayed neutron emission. This paper describes the CCONE code system indicating the concept and design of coding and inputs. Details of the formulation for modelings of the direct, pre-equilibrium and compound reactions are presented. Applications to the nuclear data evaluations such as neutron-induced reactions on actinides and medium-heavy nuclei, high-energy nucleon-induced reactions, photonuclear reaction and β-delayed neutron emission are mentioned.

{alpha}-Tocopherol impact on oxy-radical induced free radical decomposition of DMSO: Spin trapping EPR and theoretical studies

Energy Technology Data Exchange (ETDEWEB)

Jerzykiewicz, Maria, E-mail: Mariaj@wchuwr.pl [Faculty of Chemistry, Wroclaw University, 14 F. Joliot-Curie St., 50-383 Wroclaw (Poland); Cwielag-Piasecka, Irmina; Witwicki, Maciej; Jezierski, Adam [Faculty of Chemistry, Wroclaw University, 14 F. Joliot-Curie St., 50-383 Wroclaw (Poland)

2011-05-26

Graphical abstract: {alpha}-Tocopherol inhibits the oxidation of {center_dot}CH{sub 3} to {center_dot}OCH{sub 3}. Display Omitted Highlights: {yields} {alpha}-Tocopherol does not inhibit the oxidation of DMSO to {center_dot}CH{sub 3}. {yields} {alpha}-Tocopherol inhibits the oxidation of {center_dot}CH{sub 3} to {center_dot}OCH{sub 3}. {yields} {alpha}-Tocopherol does not inhibit the oxidation of PBN. {yields} The structures of observed spin adducts were theoretically confirmed. - Abstract: EPR spin trapping and theoretical methods such as density functional theory (DFT) as well as combined DFT and quadratic configuration interaction approach (DFT/QCISD) were used to identify the radicals produced in the reaction of oxy-radicals and dimethyl sulfoxide (DMSO) in the presence and absence of {alpha}-tocopherol. Additionally, the mixtures of {alpha}-tocopherol with linolenic acid and glyceryl trilinoleate as well as bioglycerols (glycerol fractions from biodiesel production) were tested. {alpha}-Tocopherol inhibited oxidation of the main decomposition product of DMSO, {center_dot}CH{sub 3} to {center_dot}OCH{sub 3} but did not prevent the transformation process of N-t-butyl-{alpha}-phenylnitrone (PBN) into 2-methyl-2-nitrosopropane (MNP). Theoretical investigations confirmed the structures of proposed spin adducts and allowed to correlate the EPR parameters observed in the experiment with the spin adducts electronic structure.

Detecting Energy Spectrum Of The Products Of Reaction 6Li(n,alpha)3H By The Home-Made Gaseous Detectors In Vietnam

International Nuclear Information System (INIS)

Luong Huu Phuoc; Phung Van Duan; Le Van Mien; Nguyen Tat Thang; Tran Hoai Nam

2008-01-01

There are shown some of results of study in designing and making first gaseous detectors of big sizes in Vietnam. The detectors were used for test measurement of detecting energy spectrum of the products of reaction 6 Li(n,alpha) 3 H caused by thermal neutrons. On the spectrum there were observed two energy peaks of tritons and alpha particles separately. In the test measurement there were used two neutron isotopic sources with total output 2x1.1x10 7 n/s. The study was implemented at Hanoi University of Technology. (author)

[Effects of intermittent hypoxic exposure on the parameter of erythrocyte and serum hypoxia inducible factor-1 alpha and erythropoietin levels].

Science.gov (United States)

Zhang, Cheng-yan; Zhang, Ji-xin; Lü, Xiao-tao; Li, Bao-yu

2009-10-01

To investigate the effects of intermittent hypoxic exposure and normoxic convalescence on the parameter of erythrocyte and serum hypoxia inducible factor-1 alpha (HIF-1alpha) and erythropoietin (EPO) levels. Rat models of intermittent hypoxic exposure were established, combined with the clinical research on volunteers experiencing the intermittent plateau work. Blood samples for red blood cell (RBC) counts, hemoglobin (Hb) and hematocrit (HCT) were collected, serum HIF-1alpha and EPO levels were measured using enzyme linked immunosorbent assay. RBC counts, Hb concentration and HCT were significantly higher than the normoxic group (P hypoxic exposure can enhance serum hypoxia inducible factor-1 alpha and erythropointin levels and the generation of red blood cells, which leads to an increase in hemoglobin concentration and hematocrit. The results have changed with the hypoxic exposure period prolonged. Normoxic convalescence after intermittent hypoxic exposure can make the related indexes reduced, and contribute to the organism recovery.

Some calculated (p,α) cross-sections using the alpha particle knock-on and triton pick-up reaction mechanisms: An optimisation of the single-step Feshbach-Kerman-Koonin (FKK) theory

Energy Technology Data Exchange (ETDEWEB)

Olise, Felix S.; Ajala, Afis; Olamiyl, Hezekiah B. [Dept. of Physics and Engineering Physics, Obafemi Awolowo University, Ile-Ife (Nigeria)

2016-04-15

The Feshbach-Kerman-Koonin (FKK) multi-step direct (MSD) theory of pre-equilibrium reactions has been used to compute the single-step cross-sections for some (p,α) reactions using the knock-on and pick-up reaction mechanisms at two incident proton energies. For the knock-on mechanism, the reaction was assumed to have taken place by the direct ejection of a preformed alpha cluster in a shell-model state of the target. But the reaction was assumed to have taken place by the pick-up of a preformed triton cluster (also bound in a shell-model state of the target core) by the incident proton for the pick-up mechanism. The Yukawa forms of potential were used for the proton-alpha (for the knock-on process) and proton-triton (for the pick-up process) interaction and several parameter sets for the proton and alpha-particle optical potentials. The calculated cross-sections for both mechanisms gave satisfactory fits to the experimental data. Furthermore, it has been shown that some combinations of the calculated distorted wave Born approximation cross-sections for the two reaction mechanisms in the FKK MSD theory are able to give better fits to the experimental data, especially in terms of range of agreement. In addition, the theory has been observed to be valid over a wider range of energy.

Some Calculated (p,α Cross-Sections Using the Alpha Particle Knock-On and Triton Pick-Up Reaction Mechanisms: An Optimisation of the Single-Step Feshbach–Kerman–Koonin (FKK Theory

Directory of Open Access Journals (Sweden)

Felix S. Olise

2016-04-01

Full Text Available The Feshbach–Kerman–Koonin (FKK multi-step direct (MSD theory of pre-equilibrium reactions has been used to compute the single-step cross-sections for some (p,α reactions using the knock-on and pick-up reaction mechanisms at two incident proton energies. For the knock-on mechanism, the reaction was assumed to have taken place by the direct ejection of a preformed alpha cluster in a shell-model state of the target. But the reaction was assumed to have taken place by the pick-up of a preformed triton cluster (also bound in a shell-model state of the target core by the incident proton for the pick-up mechanism. The Yukawa forms of potential were used for the proton-alpha (for the knock-on process and proton-triton (for the pick-up process interaction and several parameter sets for the proton and alpha-particle optical potentials. The calculated cross-sections for both mechanisms gave satisfactory fits to the experimental data. Furthermore, it has been shown that some combinations of the calculated distorted wave Born approximation cross-sections for the two reaction mechanisms in the FKK MSD theory are able to give better fits to the experimental data, especially in terms of range of agreement. In addition, the theory has been observed to be valid over a wider range of energy.

Pre-hospital treatment of bee and wasp induced anaphylactic reactions

DEFF Research Database (Denmark)

Ruiz Oropeza, Athamaica; Mikkelsen, Søren; Bindslev-Jensen, Carsten

2017-01-01

BACKGROUND: Bee and wasp stings are among the most common triggers of anaphylaxis in adults representing around 20% of fatal anaphylaxis from any cause. Data of pre-hospital treatment of bee and wasp induced anaphylactic reactions are sparse. This study aimed to estimate the incidence of bee...... only for Odense and 2009-2014 for the whole region). Discharge summaries with diagnosis related to anaphylaxis according to the International Classification of Diseases 10 (ICD-10) were reviewed to identify bee and wasp induced anaphylactic reactions. The severity of the anaphylactic reaction...... was assessed according to Sampson's severity score and Mueller's severity score. Treatment was evaluated in relation to administration of adrenaline, glucocorticoids and antihistamine. RESULTS: We identified 273 cases (Odense 2008 n = 14 and Region of Southern Denmark 2009-2014 n = 259) of bee and wasp induced...

Biological stress responses induced by alpha radiation exposure in Lemna minor

Energy Technology Data Exchange (ETDEWEB)

Van Hoeck, A.; Horemans, N.; Van Hees, M.; Nauts, R. [Belgian Nuclear Research Centre SCK-CEN (Belgium); Knapen, D.; Blust, R. [University of Antwerp (Belgium)

2014-07-01

experiments Steinberg medium was selected for further dose-response experiments to analyse additional end-points like DNA-damage and enzymes involved in detoxification of reactive oxygen species. Finally, these results enable comparison of alpha radiation-induced effects at different levels of biological complexity from metabolic pathways to morphological growth effects. This research was supported by the Fund for Scientific Research (FWO-Vlaanderen, G.A040.11N) Document available in abstract form only. (authors)

Alpha 7 nicotinic acetylcholine receptor-mediated protection against ethanol-induced neurotoxicity.

Science.gov (United States)

de Fiebre, NancyEllen C; de Fiebre, Christopher M

2003-11-01

The alpha(7)-selective nicotinic partial agonist 3-[2,4-dimethoxybenzylidene]anabaseine (DMXB) was examined for its ability to modulate ethanol-induced neurotoxicity in primary cultures of rat neurons. Primary cultures of hippocampal neurons were established from Long-Evans, embryonic day (E)-18 rat fetuses and maintained for 7 days. Ethanol (0-150 mM), DMXB (0-56 microM), or both were subsequently co-applied to cultures. Ethanol was added two additional times to the cultures to compensate for evaporation. After 5 days, neuronal viability was assessed with the MTT cell proliferation assay. Results demonstrated that ethanol reduces neuronal viability in a concentration-dependent fashion and that DMXB protects against this ethanol-induced neurotoxicity, also in a concentration-dependent fashion. These results support the suggestion that nicotinic partial agonists may be useful in treating binge drinking-induced neurotoxicity and may provide clues as to why heavy drinkers are usually smokers.

Role of tumor necrosis factor-alpha and platelet-activating factor in neoangiogenesis induced by synovial fluids of patients with rheumatoid arthritis.

Science.gov (United States)

Lupia, E; Montrucchio, G; Battaglia, E; Modena, V; Camussi, G

1996-08-01

The aim of the present study was to investigate in vivo in a mouse model the stimulation of neoangiogenesis by synovial fluids of patients with rheumatoid arthritis (RA) and to determine the role of tumor necrosis factor (TNF)-alpha and platelet-activating factor (PAF) in the formation of new vessels. Angiogenesis was studied in a mouse model in which Matrigel, injected subcutaneously, was used as a vehicle for the delivery of potential angiogenic stimuli. Synovial fluids of patients with RA but not with osteoarthritis (OA) were shown to induce neoangiogenesis. Since synovial fluid of patients with RA contained significantly higher levels of TNF-alpha-like bioactivity and of PAF than that of patients with OA, the role of these mediators was evaluated by using an anti-TNF-alpha neutralizing monoclonal antibody (mAb) and a PAF receptor antagonist, WEB 2170. When added to Matrigel, anti-TNF-alpha mAb and particularly WEB 2170 significantly reduced neoangiogenesis induced by synovial fluids of RA patients. Moreover, PAF extracted and purified from synovial fluid induced angiogenesis. These results suggest that the neoangiogenesis observed in rheumatoid synovitis may be due, at least in part, to the angiogenic effect of locally produced TNF-alpha and PAF.

Systematic trends in photonic reagent induced reactions in a homologous chemical family.

Science.gov (United States)

Tibbetts, Katharine Moore; Xing, Xi; Rabitz, Herschel

2013-08-29

The growing use of ultrafast laser pulses to induce chemical reactions prompts consideration of these pulses as "photonic reagents" in analogy to chemical reagents. This work explores the prospect that photonic reagents may affect systematic trends in dissociative ionization reactions of a homologous family of halomethanes, much as systematic outcomes are often observed for reactions between homologous families of chemical reagents and chemical substrates. The experiments in this work with photonic reagents of varying pulse energy and linear spectral chirp reveal systematic correlations between observable ion yields and the following set of natural variables describing the substrate molecules: the ionization energy of the parent molecule, the appearance energy of each fragment ion, and the relative strength of carbon-halogen bonds in molecules containing two different halogens. The results suggest that reactions induced by photonic reagents exhibit systematic behavior analogous to that observed in reactions driven by chemical reagents, which provides a basis to consider empirical "rules" for predicting the outcomes of photonic reagent induced reactions.

A complex effect of arsenite on the formation of alpha-ketoglutarate in rat liver mitochondria.

Science.gov (United States)

Lenartowicz, E

1990-12-01

This investigation presents disturbances of the mitochondrial metabolism by arsenite, a hydrophilic dithiol reagent known as an inhibitor of mitochondrial alpha-keto acid dehydrogenases. Arsenite at concentrations of 0.1-1.0 mM was shown to induce a considerable oxidation of intramitochondrial NADPH, NADH, and glutathione without decreasing the mitochondrial membrane potential. The oxidation of NAD(P)H required the presence of phosphate and was sensitive to ruthenium red, but occurred without the addition of calcium salts. Mitochondrial reactions producing alpha-ketoglutarate from glutamate and isocitrate were modulated by arsenite through various mechanisms: (i) both glutamate transaminations, with oxaloacetate and with pyruvate, were inhibited by accumulating alpha-ketoglutarate; however, at low concentrations of alpha-ketoglutarate the aspartate aminotransferase reaction was stimulated due to the increase of NAD+ content; (ii) the oxidation of isocitrate was stimulated at its low concentration only, due to the oxidation of NADPH and NADH; this oxidation was prevented by concentrations of citrate or isocitrate greater than 1 mM; (iii) the conversion of isocitrate to citrate was suppressed, presumably as a result of the decrease of Mg2+ concentration in mitochondria. Thus the depletion of mitochondrial vicinal thiol groups in hydrophilic domains disturbs the mitochondrial metabolism not only by the inhibition of alpha-keto acid dehydrogenases but also by the oxidation of NAD(P)H and, possibly, by the change in the ion concentrations.

Binding of 125I alpha-bungarotoxin to the thymus of mice

International Nuclear Information System (INIS)

Ohshima, F.; Kondo, K.; Tsubaki, T.

1978-01-01

Alpha-bungarotoxin is known to bind with nicotinic acetylcholine receptors of skeletal muscle. Binding of iodine 125-labeled alpha bungarotoxin to the murine thymus, muscle, and liver was estimated. The toxin was bound to the muscle. The thymus was also capable of binding a considerable amount of the toxin, and the binding was obviously blocked by tubocurarine chloride. Binding to the liver, an organ containing no nicotinic acetylcholine receptor, was very slight. These results may indicate the presence of nicotinic acetylcholine receptors in the thymus, which could have implications in the pathogenesis of myasthenia gravis. Degenerating myoid cells and their receptors may represent autoantigens that induce an immunological cross-reaction with the receptors of skeletal muscles, giving rise to myasthenia gravis

Synthesis of spiro-4H-pyrazole-oxindoles and fused 1H-pyrazoles via divergent, thermally induced tandem cyclization/migration of alkyne-tethered diazo compounds.

Science.gov (United States)

Zhang, Cheng; Dong, Shanliang; Zheng, Yang; He, Ciwang; Chen, Jiaolong; Zhen, Jingsen; Qiu, Lihua; Xu, Xinfang

2018-01-31

A thermally induced, substrate-dependent reaction of alkynyl diazo compounds has been developed. This transformation produces spiro-4H-pyrazole-oxindoles and fused 1H-pyrazoles in good to high yields from the corresponding alpha-cyano and alpha-sulfonyl diazo compounds. The salient features of this reaction include excellent chemoselectivity and atom-economy, mild reaction conditions, simple purification and potential for large scale production.

The 65 keV resonance in the {sup 17}O(p,alpha){sup 14}N thermonuclear reaction

Energy Technology Data Exchange (ETDEWEB)

Sergi, M.L. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Centro Siciliano di Fisica Nucleare e Struttura della Materia, Catania (Italy); Spitaleri, C. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Coc, A. [CSNSM, UMR 8609, CNRS/IN2P3and Universite Paris Sud 11, Batiment 104, 91405 Orsay Campus (France); Mukhamedzhanov, A. [Cyclotron Institute, Texas A and M University, College Station, TX 77843 (United States); Burjan, S.V. [Nuclear Physics Institute of ASCR Rez near Prague (Czech Republic); Gulino, M. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Hammache, F. [IPN, IN2P3-CNRS et Universite de Paris-Sud 11, 91406 Orsay Cedex (France); Hons, Z. [Nuclear Physics Institute of ASCR Rez near Prague (Czech Republic); Irgaziev, B. [GIK Institute of Engineering Sciences and Technology Topi District Swabi NWFP (Pakistan); Kiss, G.G. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Kroha, V. [Nuclear Physics Institute of ASCR Rez near Prague (Czech Republic); La Cognata, M. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Centro Siciliano di Fisica Nucleare e Struttura della Materia, Catania (Italy); Lamia, L.; Pizzone, R.G. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Sereville, N. de [IPN, IN2P3-CNRS et Universite de Paris-Sud 11, 91406 Orsay Cedex (France); Somorjai, E. [ATOMKI, Debrecen (Hungary)

2010-03-01

The indirect measurement of {sup 17}O(p,alpha){sup 14}N cross section was performed by means of the Trojan Horse Method. This approach allowed to investigate the ultra-low energy range (E{sub c.m.}=0-300 keV) relevant for several astrophysics environments, where two resonant levels of {sup 18}F at E{sub c.m.}{sup R}=65 keV and E{sub c.m.}{sup R}=183 keV play a significant role in the reaction rate determination.

Direct Amination of alpha-Hydroxy Amides

NARCIS (Netherlands)

Chandgude, Ajay L.; Dömling, Alexander

A TiCl4-mediated reaction for the direct amination of alpha-hydroxy amides has been developed. This simple, general, additive/base/ligand-free reaction is mediated by economical TiCl4. The reaction runs under mild conditions. This highly efficient C-N bond formation protocol is valid for diverse

Excitation functions of alpha particle induced reactions on {sup nat}Ti up to 40 MeV

Energy Technology Data Exchange (ETDEWEB)

Uddin, M.S., E-mail: md.shuzauddin@yahoo.com [Tandem Accelerator Facilities, Institute of Nuclear Science and Technology, Atomic Energy Research Establishment, Savar, Dhaka (Bangladesh); Scholten, B. [Institut für Neurowissenschaften und Medizin, INM-5:Nuklearchemie, Forschungszentrum Jülich, D-52425 Jülich (Germany)

2016-08-01

Excitation functions of the reactions {sup nat}Ti(α,x){sup 48}Cr, {sup nat}Ti(α,x){sup 48}V and {sup nat}Ti(α,x){sup 46,48}Sc were determined by the stacked-foil activation technique up to 40 MeV. The radioactivities produced in the {sup nat}Ti target were measured by γ-ray spectrometry using HPGe detector. The reaction {sup nat}Ti(α,x){sup 51}Cr was used to determine the beam parameters. New experimental values for the above reactions have been obtained. An intercomparison of our data with the available literature values has been done. The cross section results obtained in this work could be useful in defining new monitor reactions, radiation safety and isotope production.

Plasma concentrations of alpha-melanocyte-stimulating hormone are elevated in patients on chronic haemodialysis.

Science.gov (United States)

Airaghi, L; Garofalo, L; Cutuli, M G; Delgado, R; Carlin, A; Demitri, M T; Badalamenti, S; Graziani, G; Lipton, J M; Catania, A

2000-08-01

Clinical and/or laboratory signs of systemic inflammation occur frequently in patients undergoing long-term haemodialysis. It is likely, therefore, that a compensatory release of endogenous anti-inflammatory molecules occurs to limit host reactions. The aim of the present research was to determine if the potent anti-inflammatory peptide alpha-melanocyte-stimulating hormone (alpha-MSH), a pro-opiomelanocortin derivative, is increased in plasma of haemodialysis patients. Because endotoxin and cytokines induce alpha-MSH in vivo and in vitro, we also measured plasma concentrations of endotoxin, interleukin-6 (IL-6), and tumour necrosis factor alpha (TNF-alpha), and the two circulating products of activated monocytes, nitric oxide (NO) and neopterin. Thirty-five chronic haemodialysis patients, 20 patients with chronic renal failure not yet on dialysis, and 35 normal controls were included in the study. In the haemodialysis group, blood samples were obtained before and at the end of a dialysis session. Plasma alpha-MSH was measured using a double antibody radioimmunoassay, and IL-6, TNF-alpha, and neopterin using specific enzyme-linked immunosorbent assays. Plasma nitrites were determined by a colorimetric method, and endotoxin with the quantitative chromogenic LAL (limulus amoebocyte lysate) method. Mean plasma alpha-MSH was higher in haemodialysis patients than in control subjects, with the peptide concentrations being particularly elevated in dialysed patients with detectable endotoxin. High alpha-MSH concentrations were observed in the pre-dialysis samples, with no substantial change at the end of the dialysis session. Plasma concentrations of IL-6, TNF-alpha, neopterin, and NO were generally elevated in chronic haemodialysis patients and there was a negative correlation between circulating alpha-MSH and IL-6. In patients with renal failure not yet on dialysis, mean plasma alpha-MSH was similar to that of normal subjects. alpha-MSH is increased in the circulation of

Online monitoring of chemical reactions by polarization-induced electrospray ionization.

Science.gov (United States)

Meher, Anil Kumar; Chen, Yu-Chie

2016-09-21

Polarization-induced electrospray ionization (PI-ESI) is a simple technique for instant generation of gas-phase ions directly from a microliter-sized droplet for mass spectrometric analysis. A sample droplet was placed over a dielectric substrate and in proximity (2-3 mm) to the inlet of a mass spectrometer. Owing to the polarization effect induced by the high electric field provided by the mass spectrometer, the droplet was polarized and the electrospray was generated from the apex of the droplet. The polarization-induced electrospray could last for tens of seconds, which was sufficiently long to monitor fast reactions occurring within few seconds. Thus, we demonstrated the feasibility of using the droplet-based PI-ESI MS for the online monitoring of fast reactions by simply mixing two droplets (5-10 μL) containing reactants on a dielectric substrate placed in front of a mass spectrometer applied with a high voltage (-4500 V). Schiff base reactions and oxidation reactions that can generate intermediates/products within a few seconds were selected as the model reactions. The ionic reaction species generated from intermediates and products can be simultaneously monitored by PI-ESI MS in real time. We also used this approach to selectively detect acetone from a urine sample, in which acetone was derivatized in situ. In addition, the possibility of using this approach for quantitative analysis of acetone from urine samples was examined. Copyright © 2016 Elsevier B.V. All rights reserved.

Investigation of the alpha cluster states in 22Ne through the transfer induced breakup reaction 12C (18O, 18O + α)8Be at E(18O) 94.5 MeV

International Nuclear Information System (INIS)

Adhikari, S.; Basu, C.; Mitra, A.K.; Behera, B.R.; Ray, S.; Kumar, Suresh; Chatterjee, A.

2008-01-01

The nucleus 22 Ne like 18 O and 20 Ne has been sparsely investigated experimentally for an 18 O + α cluster structure. Only one experiment has reported the 22 Ne alpha cluster states using the same reaction but a much higher energy. One other experiment also reported the states with a different target and the results of these experiments are different. Therefore the 22 Ne structure has been analyzed in this work

Pre-equilibrium emission of nucleons from reactions induced by medium-energy heavy ions

International Nuclear Information System (INIS)

Korolija, M.; Holuh, E.; Cindro, N.; Hilscher, D.

1984-01-01

Recent data on fast-nucleon emission in heavy-ion-induced reactions are analysed successfully in terms of pre-equilibrium models; it is shown that the relevant parameters of those models preserve the physical meaning they have in light-ion-induced reactions. The initial exciton number obtained from a Griffin-plot analysis and the initial number of degrees of freedom, which is the relevant parameter of the modified HMB model, appear to be approximately equal for a given reaction at a given energy. It is inferred that, for heavy-ion reactions, the determination of such a parameter is substantially dominated by the centre-of-mass energy per nucleon above the Coulomb barrier, in contrast with the results of nucleon-induced reactions

Hantaan Virus Nucleocapsid Protein Binds to Importin alpha Proteins and Inhibits Tumor Necrosis Factor Alpha-Induced Activation of Nuclear Factor Kappa B

Science.gov (United States)

2008-11-19

Microbiology . All Rights Reserved. Hantaan Virus Nucleocapsid Protein Binds to Importin Proteins and Inhibits Tumor Necrosis Factor Alpha-Induced...Division, U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland 21702,1 and Department of Microbiology , Mount Sinai...34–36. 32. Prescott , J., C. Ye, G. Sen, and B. Hjelle. 2005. Induction of innate immune response genes by Sin Nombre hantavirus does not require

78Kr(α,γ) reaction of astrophysical interest in inverse kinematics and the electronic screening effect on the beta decay

International Nuclear Information System (INIS)

Ujic, P.

2011-12-01

The thesis is constituted of two different topics related to astrophysics. The titles of these topics are: 'Alpha capture reaction in inverse kinematics, measurement of 78 Kr(α,γ) 82 Sr reaction' and 'Measurement of the radioactive decay of 19 O and 19 Ne implanted in niobium'. The goal of the first part of the thesis was to establish an experimental technique for measuring radiative alpha capture reaction at low energies in inverse kinematics. The measurement of these reactions is very important in astrophysics since it will help to improve the reliability of alpha particle optical model potentials which are used for prediction of cross sections of nuclear reaction used in different astrophysical models of supernovae explosions. In this part we insisted on a technical feasibility of this type of experiment. In the second part of the thesis, we examined the influence of the environment on the beta decay probability, in particular the influence of the electronic screening of Coulomb barrier of nuclei induced by Cooper pairs in superconductors. The indication of an extremely weak effect was noticed. (author)

Chemokines, macrophage inflammatory protein-2 and stromal cell-derived factor-1{alpha}, suppress amyloid {beta}-induced neurotoxicity

Energy Technology Data Exchange (ETDEWEB)

Raman, Dayanidhi; Milatovic, Snjezana-Zaja [Department of Cancer Biology, Vanderbilt University, School of Medicine, Nashville, TN 37232 (United States); Milatovic, Dejan [Department of Pediatrics/Pediatric Toxicology, Vanderbilt University, School of Medicine, Nashville, TN 37232 (United States); Splittgerber, Ryan [Department of Cancer Biology, Vanderbilt University, School of Medicine, Nashville, TN 37232 (United States); Fan, Guo-Huang [Department of Neurobiology and Neurotoxicology, Meharry Medical College, Nashville, TN 37221 (United States); Richmond, Ann, E-mail: ann.richmond@vanderbilt.edu [VA Medical Center, Nashville, TN 37232 (United States); Department of Cancer Biology, Vanderbilt University, School of Medicine, Nashville, TN 37232 (United States)

2011-11-15

Alzheimer's disease (AD) is characterized by a progressive cognitive decline and accumulation of neurotoxic oligomeric peptides amyloid-{beta} (A{beta}). Although the molecular events are not entirely known, it has become evident that inflammation, environmental and other risk factors may play a causal, disruptive and/or protective role in the development of AD. The present study investigated the ability of the chemokines, macrophage inflammatory protein-2 (MIP-2) and stromal cell-derived factor-1{alpha} (SDF-1{alpha}), the respective ligands for chemokine receptors CXCR2 and CXCR4, to suppress A{beta}-induced neurotoxicity in vitro and in vivo. Pretreatment with MIP-2 or SDF-1{alpha} significantly protected neurons from A{beta}-induced dendritic regression and apoptosis in vitro through activation of Akt, ERK1/2 and maintenance of metalloproteinase ADAM17 especially with SDF-1{alpha}. Intra-cerebroventricular (ICV) injection of A{beta} led to reduction in dendritic length and spine density of pyramidal neurons in the CA1 area of the hippocampus and increased oxidative damage 24 h following the exposure. The A{beta}-induced morphometric changes of neurons and increase in biomarkers of oxidative damage, F{sub 2}-isoprostanes, were significantly inhibited by pretreatment with the chemokines MIP-2 or SDF-1{alpha}. Additionally, MIP-2 or SDF-1{alpha} was able to suppress the aberrant mislocalization of p21-activated kinase (PAK), one of the proteins involved in the maintenance of dendritic spines. Furthermore, MIP-2 also protected neurons against A{beta} neurotoxicity in CXCR2-/- mice, potentially through observed up regulation of CXCR1 mRNA. Understanding the neuroprotective potential of chemokines is crucial in defining the role for their employment during the early stages of neurodegeneration. -- Research highlights: Black-Right-Pointing-Pointer Neuroprotective ability of the chemokines MIP2 and CXCL12 against A{beta} toxicity. Black-Right-Pointing-Pointer MIP

Simulation study of radiation damage induced by energetic helium nuclei

CERN Document Server

Hoang Dac Luc; Hoang Dac Dat

2003-01-01

High energy alpha particles produced by neutron-induced nuclear reactions can damage severely reactor materials. Simulation of this process is described using theoretical calculation and ion irradiation experiments at different displacement doses and Helium doses.

High-throughput hydrolysis of starch during permeation across {alpha}-amylase-immobilized porous hollow-fiber membranes

Energy Technology Data Exchange (ETDEWEB)

Miura, Suguru; Kubota, Noboru; Kawakita, Hidetaka; Saito, Kyoichi E-mail: marukyo@xtal.tf.chiba-u.ac.jp; Sugita, Kazuyuki; Watanabe, Kohei; Sugo, Takanobu

2002-02-01

Two kinds of supporting porous membranes, ethanolamine (EA) and phenol (Ph) fibers, for immobilization of {alpha}-amylase were prepared by radiation-induced graft polymerization of an epoxy-group-containing monomer, glycidyl methacrylate, onto a porous hollow-fiber membrane, and subsequent ring-opening with EA and Ph, respectively. An {alpha}-amylase solution was forced to permeate radially outward through the pores of the EA and Ph fibers. {alpha}-Amylase was captured at a density of 0.15 and 6.6 g/L of the membrane by the graft chain containing 2-hydroxyethylamino and phenyl groups, respectively. A permeation pressure of 0.10 MPa provided a space velocity of 780 and 1500 h{sup -1} for the {alpha}-amylase-immobilized EA and Ph fibers, respectively. Quantitative hydrolysis of starch during permeation of a 20 g/L starch solution in the buffer across the {alpha}-amylase-immobilized Ph fiber was attained up to a space velocity of about 2000 h{sup -1}; this was achieved because of negligible diffusional mass-transfer resistance of the starch to the {alpha}-amylase due to convective flow/ whereas an enzyme reaction-controlled system was observed for the {alpha}-amylase-immobilized EA fiber.

Ketamine increases the frequency of electroencephalographic bicoherence peak on the alpha spindle area induced with propofol.

Science.gov (United States)

Hayashi, K; Tsuda, N; Sawa, T; Hagihira, S

2007-09-01

The reticular and thalamocortical system is known to play a prominent role in spindle wave activity, and the spindle wave is related to the sedative effects of anaesthetics. Recently, bispectral analysis of the EEG has been developed as a better method to indicate nonlinear regulation including the thalamocortical system linking to the cortical area. In the present study, in order to explore the interference of ketamine with the nonlinear regulation of the sub-cortical system, we examined the effect of ketamine on spindle alpha waves through the bispectral analysis. The study included 21 patients. Anaesthesia was induced and maintained using a propofol-TCI system (target-controlled infusion, with target concentration 3.5 microg ml(-1)). An A-2000 BIS monitor was used and the raw EEG signals were collected via an RS232 interface on a personal computer. Bicoherence, the normalized bispectrum, and power spectrum were analysed before and after i.v. administration of 1 mg kg(-1) racemic ketamine. Propofol caused alpha peaks in both power and bicoherence spectra, with average frequencies of 10.6 (SD 0.9) Hz and 10.7 (1.0) Hz, respectively. The addition of ketamine significantly shifted each peak to frequencies of 14.4 (1.4) Hz and 13.6 (1.5) Hz, respectively [P < 0.05, mean (SD)]. Ketamine shifted the alpha peaks of bicoherence induced by propofol to higher frequencies. This suggests that ketamine changes the alpha spindle rhythms through the modulation of the nonlinear sub-cortical reverberating network.

Cloning, expression, and mapping of allergenic determinants of alphaS1-casein, a major cow's milk allergen.

Science.gov (United States)

Schulmeister, Ulrike; Hochwallner, Heidrun; Swoboda, Ines; Focke-Tejkl, Margarete; Geller, Beate; Nystrand, Mats; Härlin, Annika; Thalhamer, Josef; Scheiblhofer, Sandra; Keller, Walter; Niggemann, Bodo; Quirce, Santiago; Ebner, Christoph; Mari, Adriano; Pauli, Gabrielle; Herz, Udo; Valenta, Rudolf; Spitzauer, Susanne

2009-06-01

Milk is one of the first components introduced into human diet. It also represents one of the first allergen sources, which induces IgE-mediated allergies in childhood ranging from gastrointestinal, skin, and respiratory manifestations to severe life-threatening manifestations, such as anaphylaxis. Here we isolated a cDNA coding for a major cow's milk allergen, alphaS1-casein, from a bovine mammary gland cDNA library with allergic patients' IgE Abs. Recombinant alphaS1-casein was expressed in Escherichia coli, purified, and characterized by circular dichroism as a folded protein. IgE epitopes of alphaS1-casein were determined with recombinant fragments and synthetic peptides spanning the alphaS1-casein sequence using microarrayed components and sera from 66 cow's milk-sensitized patients. The allergenic activity of ralphaS1-casein and the alphaS1-casein-derived peptides was determined using rat basophil leukemia cells transfected with human FcepsilonRI, which had been loaded with the patients' serum IgE. Our results demonstrate that ralphaS1-casein as well as alphaS1-casein-derived peptides exhibit IgE reactivity, but mainly the intact ralphaS1-casein induced strong basophil degranulation. These results suggest that primarily intact alphaS1-casein or larger IgE-reactive portions thereof are responsible for IgE-mediated symptoms of food allergy. Recombinant alphaS1-casein as well as alphaS1-casein-derived peptides may be used in clinical studies to further explore pathomechanisms of food allergy as well as for the development of new diagnostic and therapeutic strategies for milk allergy.

Adverse drug reactions induced by cardiovascular drugs in outpatients.

Science.gov (United States)

Gholami, Kheirollah; Ziaie, Shadi; Shalviri, Gloria

2008-01-01

Considering increased use of cardiovascular drugs and limitations in pre-marketing trials for drug safety evaluation, post marketing evaluation of adverse drug reactions (ADRs) induced by this class of medicinal products seems necessary. To determine the rate and seriousness of adverse reactions induced by cardiovascular drugs in outpatients. To compare sex and different age groups in developing ADRs with cardiovascular agents. To assess the relationship between frequencies of ADRs and the number of drugs used. This cross-sectional study was done in cardiovascular clinic at a teaching hospital. All patients during an eight months period were evaluated for cardiovascular drugs induced ADRs. Patient and reaction factors were analyzed in detected ADRs. Patients with or without ADRs were compared in sex and age by using chi-square test. Assessing the relationship between frequencies of ADRs and the number of drugs used was done by using Pearson analysis. The total number of 518 patients was visited at the clinic. ADRs were detected in 105 (20.3%) patients. The most frequent ADRs were occurred in the age group of 51-60. The highest rate of ADRs was recorded to be induced by Diltiazem (23.5%) and the lowest rate with Atenolol (3%). Headache was the most frequent detected ADR (23%). Assessing the severity and preventability of ADRs revealed that 1.1% of ADRs were detected as severe and 1.9% as preventable reactions. Women significantly developed more ADRs in this study (chi square = 3.978, PPearson=0.259, P<0.05). Monitoring ADRs in patients using cardiovascular drugs is a matter of importance since this class of medicines is usually used by elderly patients with critical conditions and underlying diseases.

Pulse radiolytic study of alpha-tocopherol radical mechanisms in ethanolic solution

International Nuclear Information System (INIS)

Jore, D.; Patterson, L.K.; Ferradini, C.

1986-01-01

Pulse radiolytic studies of alpha-tocopherol (alpha TH) oxidation-reduction processes were carried out with low doses (5 Gy) of high-energy electrons in O 2 -, N 2 -, and air-saturated ethanolic solutions. Depending on the concentration of oxygen in solution, two different radicals, A . and B ., were observed. The first, A ., was obtained under N 2 and results from alpha TH reaction with solvated electron (k alpha TH + e-solv = 3.4 X 10(8) mol-1 liter s-1) and with H 3 C-CH-OH, (R.) (k alpha TH + R. = 5 X 10(5) mol-1 liter s-1). B., observed under O 2 , is produced by alpha TH reaction with RO 2 . peroxyl radicals (k alpha TH + RO 2 . = 9.5 X 10(4) mol-1 liter s-1)

Reaction mechanism of hydroxymaleimide induced by γ-irradiation in alcohol solvents

International Nuclear Information System (INIS)

Nakagawa, Seiko

2010-01-01

Methanol and 2-propanol solutions of hydroxymaleimide were irradiated with γ-ray and mechanism of its γ-irradiation-induced reactions was investigated through final-product analyses using high performance liquid chromatography (HPLC) coupled with mass spectroscopy. An addition reaction of a solvent radical toward hydroxymaleimide was dominant among its oxygen-free γ-irradiation-induced reactions in its alcohol solutions while it is known that electron attachment toward hydroxyphthalimide or hydroxysuccinimide is dominant among their γ-irradiation-induced reactions. The radical adduct abstracts hydrogen from solvent molecule to re-produce a solvent radical. Therefore, the degradation efficiency of hydroxymaleimide was more than ten times larger than that of hydroxyphthalimide and hydroxysuccinimide. Dimer was also produced through electron attachment process in the solutions of hydroxymaleimide. In addition, it was found that the degradation efficiency increased with decrease in dose rate. An additional reaction of a solvent radical toward hydroxymaleimide competes with a radical-radical recombination. The latter was reduced, with the former leading to efficient degradation of hydroxymaleimide increased by irradiation at lower dose rate. On the contrary, the production yield of the adduct radical as well as the degradation efficiency of hydroxymaleimide was inhibited in the presence of oxygen.

Reaction mechanism of hydroxymaleimide induced by γ-irradiation in alcohol solvents

International Nuclear Information System (INIS)

Nakagawa, Seiko

2010-01-01

Methanol and 2-propanol solutions of hydroxymaleimide were irradiated with γ-ray and mechanism of its γ-irradiation-induced reactions was investigated through final-product analyses using high performance liquid chromatography (HPLC) coupled with mass spectroscopy. An addition reaction of a solvent radical toward hydroxymaleimide was dominant among its oxygen-free γ-irradiation-induced reactions in its alcohol solutions while it is known that electron attachment toward hydroxyphthalimide or hydroxysuccinimide is dominant among their γ-irradiation-induced reactions. The radical adduct abstracts hydrogen from solvent molecule to re-produce a solvent radical. Therefore, the degradation efficiency of hydroxymaleimide was more than 10 times larger than that of hydroxyphthalimide and hydroxysuccinimide. Dimer was also produced through electron attachment process in the solutions of hydroxymaleimide. In addition, it was found that the degradation efficiency increased with decreasing the dose rate. An addition reaction of a solvent radical toward hydroxymaleimide competes with a radical-radical recombination. The latter was reduced and the former leading to efficient degradation of hydroxymaleimide increased by irradiation at lower dose rate. On the contrary, the production yield of the adduct radical as well as the degradation efficiency of hydroxymaleimide was inhibited in the presence of oxygen.

Simulation study of radiation damage induced by energetic helium nuclei

International Nuclear Information System (INIS)

Hoang Dac Luc; Vo Tuong Hanh; Hoang Dac Dat

2003-01-01

High energy alpha particles produced by neutron-induced nuclear reactions can damage severely reactor materials. Simulation of this process is described using theoretical calculation and ion irradiation experiments at different displacement doses and Helium doses. (author)

Photon- and pion-induced reactions in the few body systems

International Nuclear Information System (INIS)

Laget, J.M.

1985-05-01

The study of the interplay of the degrees of freedom of the many nuclear system and the internal degrees of freedom of its constituents is reviewed. First nucleon-nucleon interaction mechanisms are recalled in relation to the interaction range. It appears that pion and photon induced reactions should provide two complementary ways to disentangle these various mechanisms. Most of pion and photon induced reactions, performed until now, can be understood in terms of nucleons, pions and deltas. But after a short description of the method of analysis of the reactions it is shown that this agreement is achieved at the price of the adjustment of two parameters (the πNN form factor and the rho-nucleon coupling contant) which may simulate more subtle short range effects. Then the relevance of the analysis of the same reactions in terms of quark degrees of freedom is discussed briefly

Binding of /sup 125/I alpha-bungarotoxin to the thymus of mice

Energy Technology Data Exchange (ETDEWEB)

Ohshima, F.; Kondo, K.; Tsubaki, T.

1978-01-01

Alpha-bungarotoxin is known to bind with nicotinic acetylcholine receptors of skeletal muscle. Binding of iodine 125-labeled alpha bungarotoxin to the murine thymus, muscle, and liver was estimated. The toxin was bound to the muscle. The thymus was also capable of binding a considerable amount of the toxin, and the binding was obviously blocked by tubocurarine chloride. Binding to the liver, an organ containing no nicotinic acetylcholine receptor, was very slight. These results may indicate the presence of nicotinic acetylcholine receptors in the thymus, which could have implications in the pathogenesis of myasthenia gravis. Degenerating myoid cells and their receptors may represent autoantigens that induce an immunological cross-reaction with the receptors of skeletal muscles, giving rise to myasthenia gravis.

Differential modulation of a radiation-induced bystander effect in glioblastoma cells by pifithrin-alpha and wortmannin

Energy Technology Data Exchange (ETDEWEB)

Shao Chunlin, E-mail: clshao@shmu.edu.c [Institute of Radiation Medicine, Fudan University, No. 2094 Xie-Tu Road, Shanghai 200032 (China); Zhang Jianghong [Institute of Radiation Medicine, Fudan University, No. 2094 Xie-Tu Road, Shanghai 200032 (China); Prise, Kevin M. [Centre for Cancer Research and Cell Biology, Queen' s University Belfast, Lisburn Road, Belfast BT9 7AB (United Kingdom)

2010-03-15

The implication of radiation-induced bystander effect (RIBE) for both radiation protection and radiotherapy has attracted significant attention, but a key question is how to modulate the RIBE. The present study found that, when a fraction of glioblastoma cells in T98G population were individually targeted with precise helium particles through their nucleus, micronucleus (MN) were induced and its yield increased non-linearly with radiation dose. After co-culturing with irradiated cells, additional MN could be induced in the non-irradiated bystander cells and its yield was independent of irradiation dose, giving direct evidence of a RIBE. Further results showed that the RIBE could be eliminated by pifithrin-alpha (p53 inhibitor) but enhanced by wortmannin (PI3K inhibitor). Moreover, it was found that nitric oxide (NO) contributed to this RIBE, and the levels of NO of both irradiated cells and bystander cells could be extensively diminished by pifithrin-alpha but insignificantly reduced by wortmannin. Our results indicate that RIBE can be modulated by p53 and PI3K through a NO-dependent and NO-independent pathway, respectively.

Correlations between the alpha particles and ejectiles in the 208 MeV 14N on 93Nb reaction at three different ejectile angles

International Nuclear Information System (INIS)

Fukuda, T.; Ishihara, M.; Tanaka, M.; Ogata, H.; Miura, I.; Inoue, M.; Shimoda, T.; Katori, K.; Nakayama, S.

1983-01-01

The in plane correlations between alpha particles and various ejectiles were investigated in the reaction of 208 MeV 14 N on 93 Nb at theta/sub HI/ = +22 0 , +50 0 , and +80 0 . There were three sources of coincident alpha particles: (i) the sequential alpha decay of the excited ejectiles, (ii) the equilibrium alpha emission from the targetlike fragments, and (iii) the nonequilibrium process. Process (i) contributed mainly to the cross sections with the angular range of theta/sub α/ close to theta/sub HI/. Process (ii) contributed to the lowest part of the alpha energy spectra irrespectively of theta/sub HI/ and theta/sub α/. The remaining part was ascribed to process (iii). For this process the differential coincidence cross section of the lower energy part of the alpha particles was approximately factorized as d 4 sigma/dΩ/sub HI/dΩ/sub α/dE/sub HI/dE/sub α/ = K (d 2 sigma/dΩ/sub HI/dE/sub HI/)/sub singles/ (d 2 sigma/dΩ/sub α/dE/sub α/)/sub singles/ with Kapprox.0.4/b, whereas the higher energy part of the alpha particles emitted at the forward angles had a tendency to coincide weakly with the ejectiles emitted at the backward angles (theta/sub HI/ = +50 0 and +80 0 ) as compared to the lower energy part of the alpha particles

Remote Optical Detection of Alpha Radiation

International Nuclear Information System (INIS)

Sand, J.; Hannuksela, V.; Toivonen, J.; Ihantola, S.; Peraejaervi, K.; Toivonen, H.

2010-01-01

Alpha emitting radiation sources are typically hard to detect with conventional detectors due to the short range of alpha particles in the air. However, previous studies have shown that remote detection of alpha radiation is possible by measuring the ionization-induced fluorescence of air molecules. The alpha-induced ultraviolet (UV) light is mainly emitted by molecular nitrogen and its fluorescence properties are well known. The benefit of this method is the long range of UV photons in the air. Secondly, the detection is possible also under a strong beta and gamma radiation backgrounds as they do not cause localized molecular excitation. In this work, the optical detection was studied using two different detection schemes; spectral separation of fluorescence from the background lighting and coincidence detection of UV photons originating from a single radiative decay event. Our spectrally integrated measurements have shown that one alpha decay event yields up to 400 fluorescence photons in the air and all these UV photons are induced in a 5 ns time-window. On the other hand, the probability of a background coincidence event in 5 ns scale is very rare compared to the number of background photons. This information can be applied in fluorescence coincidence filtering to discriminate the alpha radiation initiated fluorescence signal from much more intense background lighting. A device called HAUVA (Handheld Alpha UV Application) was built during this work for demonstration purposes. HAUVA utilizes spectral filtering and it is designed to detect alpha emitters from a distance of about 40 cm. Using specially selected room lighting, the device is able to separate 1 kBq alpha emitter from the background lighting with 1 second integration time. (author)

Summary of alpha-neutron sources in GADRAS

International Nuclear Information System (INIS)

Mitchell, Dean James; Thoreson, Gregory G.; Harding, Lee T.

2012-01-01

A common source of neutrons for calibration and testing is alpha-neutron material, named for the alpha-neutron nuclear reaction that occurs within. This material contains a long-lived alpha-emitter and a lighter target element. When the alpha particle from the emitter is absorbed by the target, neutrons and gamma rays are released. Gamma Detector Response and Analysis Software (GADRAS) includes built-in alpha-neutron source definitions for AcC, AmB, AmBe, AmF, AmLi, CmC, and PuC. In addition, GADRAS users may create their own alpha-neutron sources by placing valid alpha-emitters and target elements in materials within their one-dimensional models (1DModel). GADRAS has the ability to use pre-built alpha-neutron sources for plotting or as trace-sources in 1D models. In addition, if any material (existing or user-defined) specified in a 1D model contains both an alpha emitter in conjunction with a target nuclide, or there is an interface between such materials, then the appropriate neutron-emission rate from the alpha-neutron reaction will be computed. The gamma-emissions from these sources are also computed, but are limited to a subset of nine target nuclides. If a user has experimental data to contribute to the alpha-neutron gamma emission database, it may be added directly or submitted to the GADRAS developers for inclusion. The gadras.exe.config file will be replaced when GADRAS updates are installed, so sending the information to the GADRAS developers is the preferred method for updating the database. This is also preferable because it enables other users to benefit from your efforts.

Reaction mechanism and spectroscopy of transfer reactions induced by heavy ions

International Nuclear Information System (INIS)

Lemaire, M.-C.

1977-01-01

The specific features displayed by data on heavy ion elastic and inelastic angular distributions are discussed, and their physical origin is pointed out from semi-classical calculations in counterpart ambiguities in the phenomenological description of the optical potential appear. Two nucleon transfer reactions induced by heavy ions successfully point out important contributions of a two-step process where the transfer is proceeding via target and residual nucleus inelastic excitation. At incident energies not too high above the Coulomb barrier, such process produces clear shape changes between different final state angular distributions. At higher incident energy, the angular distributions are forward peaked and display oscillations for both mechanisms. As for four-nucleon transfer reactions, the existing data suggest that the nucleons are well transferred into a Os relative

alpha,beta-unsaturated 2-acyl imidazoles as a practical class of dienophiles for the DNA-Based catalytic asymmetric diels-alder reaction in water

NARCIS (Netherlands)

Boersma, A.J.; Feringa, B.L.; Roelfes, G.

2007-01-01

alpha,beta-Unsaturated 2-acyl imidazoles are a novel and practical class of dienophiles for the DNA-based catalytic asymmetric Diels-Alder reaction in water. The Diels-Alder products are obtained with very high diastereoselectivities and enantioselectivities in the range of 83-98%. The catalytic

short communication simple grinding-induced reactions of 2

African Journals Online (AJOL)

Preferred Customer

SIMPLE GRINDING-INDUCED REACTIONS OF 2-AMINOBENZYL ... As part of our broad interest in the chemistry of heterocyclic compounds [10, 11], the .... study grant) and the University of Botswana (THT study grant) for financial support, Dr.

[Alpha-melanocyte-stimulating hormone. From bench to bedside].

Science.gov (United States)

Böhm, M; Luger, T A

2010-06-01

Alpha-melanocyte-stimulating hormone (alpha-MSH) is a tridecapeptide that is produced by the skin itself from the precursor proopiomelanocortin. It crucially mediates ultraviolet light-induced tanning after binding to melanocortin-1 receptors (MC-1R) expressed on the surface of epidermal melanocytes. The potent pigment-inducing and also cytoprotective actions of alpha-MSH are the rationale for the performance of first phase II clinical trials with Nle4-D-Phe7-alpha-MSH (NDP-alpha-MSH), a subcutaneously administered synthetic and superpotent alpha-MSH analogue, in patients with photodermatoses such as erythropoietic protoporphyria. Since alpha-MSH has shown promising anti-inflammatory and antifibrotic properties in numerous preclinical studies, it will be most interesting to evaluate these effects in further clinical pilot studies with NDP-alpha-MSH. In addition to alpha-MSH analogues, truncated tripeptides such as KDPT which do not bind to MC-1R but have sustained anti-inflammatory properties are currently emerging as another novel therapeutic strategy in dermatology.

Neutron-induced cross sections of short-lived nuclei via the surrogate reaction method

Directory of Open Access Journals (Sweden)

Morel P.

2011-10-01

Full Text Available The measurement of neutron-induced cross sections of short-lived nuclei is extremely difficult due to the radioactivity of the samples. The surrogate reaction method is an indirect way of determining cross sections for nuclear reactions that proceed through a compound nucleus. This method presents the advantage that the target material can be stable or less radioactive than the material required for a neutron-induced measurement. We have successfully used the surrogate reaction method to extract neutron-induced fission cross sections of various short-lived actinides. In this work, we investigate whether this technique can be used to determine neutron-induced capture cross sections in the rare-earth region.

Neutron-induced cross sections of short-lived nuclei via the surrogate reaction method

Directory of Open Access Journals (Sweden)

Tassan-Got L.

2012-02-01

Full Text Available The measurement of neutron-induced cross sections of short-lived nuclei is extremely difficult due to the radioactivity of the samples. The surrogate reaction method is an indirect way of determining cross sections for nuclear reactions that proceed through a compound nucleus. This method presents the advantage that the target material can be stable or less radioactive than the material required for a neutron-induced measurement. We have successfully used the surrogate reaction method to extract neutron-induced fission cross sections of various short-lived actinides. In this work, we investigate whether this technique can be used to determine neutron-induced capture cross sections in the rare-earth region.

In vivo administration of interferon alpha and interleukin 2 induces proliferation of lymphoid cells in the organs of mice

International Nuclear Information System (INIS)

Puri, R.K.; Travis, W.D.; Rosenberg, S.A.

1990-01-01

We have previously shown that interleukin 2 (IL-2) synergizes with interferon alpha (IFN-alpha) in mediating the regression of established pulmonary and hepatic metastases and the reduction of intradermal tumor in various murine tumor models. To understand the mechanism of synergy, we have examined lymphoid cell proliferation in various organs of mice in response to IL-2 and IFN-alpha administration. We have utilized a technique for labeling newly synthesized DNA in vivo with 5-[125I]iodo-2'-deoxyuridine to examine proliferation of endogenous cells in response to IL-2 and IL-2 plus IFN-alpha. A proliferation index was calculated by dividing cpm in the tissues treated with cytokines by cpm obtained in corresponding tissues of control mice. After 4 days of IL-2 administration, a significant uptake of 5-[125I]iodo-2'-deoxyuridine was observed in the lungs, liver, kidneys, and spleen (proliferation index of 13, 10.3, 3.6, and 3.2, respectively). IFN-alpha alone mediated very little incorporation of radiolabel but when administered in combination with IL-2 a reduction of IL-2-induced proliferation was seen on day 4. For example 19,272 +/- 4,556 cpm (mean +/- SE) were obtained in the liver of IL-2-treated mice, compared to 8,103 +/- 2,111 cpm in livers of IL-2 plus IFN-alpha-treated mice (P less than 0.05). Similar inhibition of IL-2-induced proliferation was observed in the lungs, kidneys, and spleen. In contrast, on days 7 or 8, higher uptake of radiolabel was obtained in IFN-alpha plus IL-2-treated lungs, liver, and kidneys, compared to organs of mice treated with IL-2 alone or IFN-alpha alone. A proliferation index of 30.5, 9.8, and 10 was obtained in the lungs, liver, and kidneys of IL-2- plus IFN-alpha-treated animals, compared to 9.6, 3.6, and 5.5 in the corresponding organs of IL-2-treated mice

Laser induced nuclear reactions

International Nuclear Information System (INIS)

Ledingham, Ken; McCanny, Tom; Graham, Paul; Fang Xiao; Singhal, Ravi; Magill, Joe; Creswell, Alan; Sanderson, David; Allott, Ric; Neely, David; Norreys, Peter; Santala, Marko; Zepf, Matthew; Watts, Ian; Clark, Eugene; Krushelnick, Karl; Tatarakis, Michael; Dangor, Bucker; Machecek, Antonin; Wark, Justin

1998-01-01

Dramatic improvements in laser technology since 1984 have revolutionised high power laser technology. Application of chirped-pulse amplification techniques has resulted in laser intensities in excess of 10 19 W/cm 2 . In the mid to late eighties, C. K. Rhodes and K. Boyer discussed the possibility of shining laser light of this intensity onto solid surfaces and to cause nuclear transitions. In particular, irradiation of a uranium target could induce electro- and photofission in the focal region of the laser. In this paper it is shown that μCi of 62 Cu can be generated via the (γ,n) reaction by a laser with an intensity of about 10 19 Wcm -2

PGC-1{alpha} is required for AICAR induced expression of GLUT4 and mitochondrial proteins in mouse skeletal muscle

DEFF Research Database (Denmark)

Leick, Lotte; Fentz, Joachim; Biensø, Rasmus S

2010-01-01

We tested the hypothesis that repeated activation of AMPK induces mitochondrial and glucose membrane transporter gene/protein expression via a peroxisome proliferator activated receptor Upsilon co-activator (PGC)-1alpha dependent mechanism. Whole body PGC-1alpha knockout (KO) and littermate wild...... GLUT4, cytochrome c oxidase (COX)I and cytochrome (cyt) c protein expression ~10-40% relative to saline in white muscles of the WT mice, but not of the PGC-1alpha KO mice. In line, GLUT4 and cyt c mRNA content increased 30-60% 4h after a single AICAR injection relative to saline only in WT mice. One...... and PGC-1alpha KO mice. In conclusion, we here provide genetic evidence for a major role of PGC-1alpha in AMPK mediated regulation of mitochondrial and glucose membrane transport protein expression in skeletal muscle....

Laser-induced reaction alumina coating on ceramic composite

Science.gov (United States)

Xiao, Chenghe

Silicon carbide ceramics are susceptible to corrosion by certain industrial furnace environments. It is also true for a new class of silicon carbide-particulate reinforced alumina-matrix composite (SiCsb(P)Alsb2Osb3) since it contains more than 55% of SiC particulate within the composite. This behavior would limit the use of SiCsb(P)Alsb2Osb3 composites in ceramic heat exchangers. Because oxide ceramics corrode substantially less in the same environments, a laser-induced reaction alumina coating technique has been developed for improving corrosion resistance of the SiCsb(P)Alsb2Osb3 composite. Specimens with and without the laser-induced reaction alumina coating were subjected to corrosion testing at 1200sp°C in an air atmosphere containing Nasb2COsb3 for 50 ˜ 200 hours. Corroded specimens were characterized via x-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrometer (EDS). The uncoated SiCsbP/Alsb2Osb3 composite samples experienced an initial increase in weight during the exposure to Nasb2COsb3 at 1200sp°C due to the oxidation of residual aluminum metal in the composite. There was no significant weight change difference experienced during exposure times between 50 and 200 hours. The oxidation layer formed on the as-received composite surface consisted of Si and Alsb2Osb3 (after washing with a HF solution). The oxidation layer grew outward and inward from the original surface of the composite. The growth rate in the outward direction was faster than in the inward direction. The formation of the Si/Alsb2Osb3 oxidation layer on the as-received composite was nonuniform, and localized corrosion was observed. The coated samples experienced very little mass increase. The laser-induced reaction alumina coating effectively provided protection for the SiCsbP/Alsb2Osb3 composite by keeping the corrodents from contacting the composite and by the formation of some refractory compounds such as Nasb2OAlsb2Osb3SiOsb2 and Nasb2Alsb{22}Osb

[Cellular adhesion signal transduction network of tumor necrosis factor-alpha induced hepatocellular carcinoma cells].

Science.gov (United States)

Zheng, Yongchang; Du, Shunda; Xu, Haifeng; Xu, Yiyao; Zhao, Haitao; Chi, Tianyi; Lu, Xin; Sang, Xinting; Mao, Yilei

2014-11-18

To systemically explore the cellular adhesion signal transduction network of tumor necrosis factor-alpha (TNF-α)-induced hepatocellular carcinoma cells with bioinformatics tools. Published microarray dataset of TNF-α-induced HepG2, human transcription factor database HTRI and human protein-protein interaction database HPRD were used to construct and analyze the signal transduction network. In the signal transduction network, MYC and SP1 were the key nodes of signaling transduction. Several genes from the network were closely related with cellular adhesion.Epidermal growth factor receptor (EGFR) is a possible key gene of effectively regulating cellular adhesion during the induction of TNF-α. EGFR is a possible key gene for TNF-α-induced metastasis of hepatocellular carcinoma.

Ciclização do lapachol induzida por sais de tálio III Cyclyzation of lapachol induced by thallium salts

Directory of Open Access Journals (Sweden)

Carlos Magno R. Ribeiro

2008-01-01

Full Text Available This work describes the cyclization of lapachol (1 induced by thallium triacetate (TTA and thallium trinitrate (TTN in several solvents using magnetic stirring and under microwave irradiation. alpha-Xyloidone (2 - dehydro-alpha-lapachone - was obtained as the main product in these reactions in 20 75% yield. However, rhinacanthin-A (4 was isolated as main product in a 40% yield, using TTA and acetic anhydride:water (1:1 as solvent, and dehydro-iso-alpha-lapachone (3 in 21% yield, using TTA and dichloromethane as solvent. The reaction time decreased drastically under microwave conditions, but the yields of these reactions were not the expected.

Selective population of high-j states via heavy-ion-induced transfer reactions

International Nuclear Information System (INIS)

Bond, P.D.

1982-01-01

One of the early hopes of heavy-ion-induced transfer reactions was to populate states not seen easily or at all by other means. To date, however, I believe it is fair to say that spectroscopic studies of previously unknown states have had, at best, limited success. Despite the early demonstration of selectivity with cluster transfer to high-lying states in light nuclei, the study of heavy-ion-induced transfer reactions has emphasized the reaction mechanism. The value of using two of these reactions for spectroscopy of high spin states is demonstrated: 143 Nd( 16 O, 15 O) 144 Nd and 170 Er( 16 O, 15 Oγ) 171 Er

Alpha-particle irradiation induced defects in SiO2 films of Si-SiO2 structures

International Nuclear Information System (INIS)

Koman, B.P.; Gal'chynskyy, O.V.; Kovalyuk, R.O.; Shkol'nyy, A.K.

1996-01-01

The aim of the work was to investigate alpha-particle irradiation induced defects in Si-SiO 2 structures by means of the thermostimulated discharge currents (TSDC) analysis. The object of investigation were (p-Si)-SiO 2 structures formed by a combined oxidation of the industrial p-Si wafers in dry and wet oxygen at temperature of 1150 C. The TSD currents were investigated in the temperature range between 90 and 500 K under linear heating rate. Pu 238 isotopes were the source of alpha-particles with an energy of 4-5 MeV and a density of 5.10 7 s -1 cm -2 . The TSD current curves show two peculiar maxima at about 370 and 480 K. Alpha-particle irradiation doesn't affect the general shape of the TSDC curves but leads to a shift of the maximum at 370 K and reduces the total electret charge which is accumulated in the Si-SiO 2 structures during polarization. The energy distribution function of the defects which are involved in SiO 2 polarization has been calculated. It showes that defects with activation energies of about 0.8 and 1.0 eV take part in forming the electret state, and these activation energies have certain energy distributions. It has been found that the TSDC maximum at 370 K has space charge nature and is caused by migration of hydrogen ions. In irradiated samples hydrogen and natrium ions localize on deeper trapping centres induced by alpha-particle irradiation. (orig.)

Charged-particle induced thermonuclear reaction rates: a compilation for astrophysics

International Nuclear Information System (INIS)

Grama, Cornelia; Angulo, C.; Arnould, M.

2000-01-01

The rapidly growing wealth of nuclear data becomes less and less easily accessible to the astrophysics community. Mastering this volume of information and making it available in an accurate and usable form for incorporation into stellar evolution or nucleosynthesis models become urgent goals of prime necessity. we report on the results of the European network NACRE (Nuclear Astrophysics Compilation of REaction rates). The principal motivation for the setting-up of the NACRE network has been the necessity of building up a well-documented and detailed compilation of rates for charged-particle induced reactions on stable targets up to Si and on unstable nuclei of special significance in astrophysics. This work is meant to supersede the only existing compilation of reaction rates issued by Fowler and collaborators. The cross section data and/or resonance parameters for a total of 86 charged-particle induced reactions are given and the corresponding reaction rates are calculated and given in tabular form. When cross section data are not available in the whole needed range of energies, the theoretical predictions obtained in the framework of the Hauser-Feshbach model is used. Uncertainties are analyzed and realistic upper and lower bounds of the rates are determined. Reverse reaction rates and analytical approximations of the adopted rates are also provided. (authors)

Charged-particle induced thermonuclear reaction rates: a compilation for astrophysics

International Nuclear Information System (INIS)

Grama, Cornelia

1999-01-01

The rapidly growing wealth of nuclear data becomes less and less easily accessible to the astrophysics community. Mastering this volume of information and making it available in an accurate and usable form for incorporation into stellar evolution or nucleosynthesis models become urgent goals of prime necessity. We report on the results of the European network NACRE (Nuclear Astrophysics Compilation of REaction rates). The principal motivation for the setting-up of the NACRE network has been the necessity of building up a well-documented and detailed compilation of rates for charged -particle induced reactions on stable targets up to Si and on unstable nuclei of special significance in astrophysics. This work is meant to supersede the only existing compilation of reaction rates issued by Fowler and collaborators. The cross section data and/or resonance parameters for a total of 86 charged-particle induced reactions are given and the corresponding reaction rates are calculated and given in tabular form. When cross section data are not available in the whole needed range of energies the theoretical predictions obtained in the framework of the Hauser-Feshbach model are used. Uncertainties are analyzed and realistic upper and lower bounds of the rates are determined. Reverse reaction rates and analytical approximations of the adopted rates are also provided. (author)

Contributions to the study of heavy and superheavy nuclei stability in alpha-decay

International Nuclear Information System (INIS)

Silisteanu, I.

1978-01-01

Alpha-decay is treated in this work on the complete analogy of transfer reactions by means of nuclear shell models with continuous spectrum nucleons. Certain phenomenologically obtained or microscope evaluated data on low energy interactions between alpha-particles and nuclei, when related to nuclear structure data within the unified theory of nuclear reactions, allow of an improved accuracy in determining the alpha-particle wave function as well as of an estimation of alpha-probabilities in good keeping with experimental ones. The problem of alpha lifetimes thus narrows to the resolution of some homogeneous and inhomogeneous differential equations systems including the optic potential and the alpha formfactors. (author)

Study of the (p,d3He) reaction as a quasi-free reaction process

International Nuclear Information System (INIS)

Cowley, A.A.; Roos, P.G.; Chant, N.S.; Woody, R. III; Holmgren, H.D.; Goldberg, D.A.

1976-11-01

The (p,d 3 He) reaction on 6 Li, 7 Li, 9 Be, and 12 C has been investigated in conjunction with studies of the (p,pα) reaction on the same targets. Coincident data for all four targets were obtained at a bombarding energy of 100 MeV for numerous angle pairs in order to test the reaction mechanism. Comparisons of the (p,d 3 He) data to both (p,pα) data and distorted wave impulse approximation calculations (DWIA) indicate a dominance of the direct quasi-free reaction process (p + alpha yields d + 3 He). The absolute alpha-particle spectroscopic factors extracted using DWIA analysis are in agreement with the values obtained in the (p,pα) reaction

Measurements of DT alpha particle loss near the outer midplane of TFTR

International Nuclear Information System (INIS)

Zweben, S.J.; Darrow, D.S.; Herrmann, H.W.; Redi, M.H.; Schivell, J.; White, R.B.

1995-07-01

Measurements of DT alpha particle loss to the outer midplane region of TFTR have been made using a radially movable scintillator detector. The conclusion from this data is that mechanisms determining the DT alpha loss to the outer midplane are not substantially different from those for DD fusion products. Some of these results are compared with a simplified theoretical model for TF ripple-induced alpha loss, which is expected to be the dominant classical alpha loss mechanism near the outer midplane. An example of plasma-driven MHD-induced alpha particle loss is shown, but no signs of any ''collective'' alpha instability-induced alpha loss have yet been observed

Inhibition of ribosome recruitment induces stress granule formation independently of eukaryotic initiation factor 2alpha phosphorylation.

Science.gov (United States)

Mazroui, Rachid; Sukarieh, Rami; Bordeleau, Marie-Eve; Kaufman, Randal J; Northcote, Peter; Tanaka, Junichi; Gallouzi, Imed; Pelletier, Jerry

2006-10-01

Cytoplasmic aggregates known as stress granules (SGs) arise as a consequence of cellular stress and contain stalled translation preinitiation complexes. These foci are thought to serve as sites of mRNA storage or triage during the cell stress response. SG formation has been shown to require induction of eukaryotic initiation factor (eIF)2alpha phosphorylation. Herein, we investigate the potential role of other initiation factors in this process and demonstrate that interfering with eIF4A activity, an RNA helicase required for the ribosome recruitment phase of translation initiation, induces SG formation and that this event is not dependent on eIF2alpha phosphorylation. We also show that inhibition of eIF4A activity does not impair the ability of eIF2alpha to be phosphorylated under stress conditions. Furthermore, we observed SG assembly upon inhibition of cap-dependent translation after poliovirus infection. We propose that SG modeling can occur via both eIF2alpha phosphorylation-dependent and -independent pathways that target translation initiation.

Fragment mass distribution of proton-induced spallation reaction with intermediate energy

International Nuclear Information System (INIS)

Fan Sheng; Ye Yanlin; Xu Chuncheng; Chen Tao; Sobolevsky, N.M.

2000-01-01

The test of part benchmark of SHIELD code is finished. The fragment cross section and mass distribution and excitation function of the residual nuclei from proton-induced spallation reaction on thin Pb target with intermediate energy have been calculated by SHIELD code. And the results are in good agreement with measured data. The fragment mass distribution of the residual nuclei from proton-induced spallation reaction on thick Pb target with incident energy 1.6 GeV have been simulated

Charged particle induced thermonuclear reaction rates: a compilation for astrophysics

International Nuclear Information System (INIS)

Grama, C.

1999-01-01

We report on the results of the European network NACRE (Nuclear Astrophysics Compilation of REaction rates). The principal reason for setting up the NACRE network has been the necessity of building up a well-documented and detailed compilation of rates for charged-particle induced reactions on stable targets up to Si and on unstable nuclei of special significance in astrophysics. This work is meant to supersede the only existing compilation of reaction rates issued by Fowler and collaborators. The main goal of NACRE network was the transparency in the procedure of calculating the rates. More specifically this compilation aims at: 1. updating the experimental and theoretical data; 2. distinctly identifying the sources of the data used in rate calculation; 3. evaluating the uncertainties and errors; 4. providing numerically integrated reaction rates; 5. providing reverse reaction rates and analytical approximations of the adopted rates. The cross section data and/or resonance parameters for a total of 86 charged-particle induced reactions are given and the corresponding reaction rates are calculated and given in tabular form. Uncertainties are analyzed and realistic upper and lower bounds of the rates are determined. The compilation is concerned with the reaction rates that are large enough for the target lifetimes shorter than the age of the Universe, taken equal to 15 x 10 9 y. The reaction rates are provided for temperatures lower than T = 10 10 K. In parallel with the rate compilation a cross section data base has been created and located at the site http://pntpm.ulb.ac.be/nacre..htm. (authors)

Coronin-1A links cytoskeleton dynamics to TCR alpha beta-induced cell signaling.

Directory of Open Access Journals (Sweden)

Bénédicte Mugnier

Full Text Available Actin polymerization plays a critical role in activated T lymphocytes both in regulating T cell receptor (TCR-induced immunological synapse (IS formation and signaling. Using gene targeting, we demonstrate that the hematopoietic specific, actin- and Arp2/3 complex-binding protein coronin-1A contributes to both processes. Coronin-1A-deficient mice specifically showed alterations in terminal development and the survival of alpha beta T cells, together with defects in cell activation and cytokine production following TCR triggering. The mutant T cells further displayed excessive accumulation yet reduced dynamics of F-actin and the WASP-Arp2/3 machinery at the IS, correlating with extended cell-cell contact. Cell signaling was also affected with the basal activation of the stress kinases sAPK/JNK1/2; and deficits in TCR-induced Ca2+ influx and phosphorylation and degradation of the inhibitor of NF-kappaB (I kappa B. Coronin-1A therefore links cytoskeleton plasticity with the functioning of discrete TCR signaling components. This function may be required to adjust TCR responses to selecting ligands accounting in part for the homeostasis defect that impacts alpha beta T cells in coronin-1A deficient mice, with the exclusion of other lympho/hematopoietic lineages.

The use of alpha-methyl-D-glucoside, a synthetic analogue of maltose, as inducer of amylase by Aspergillus sp in solid-state and submerged fermentations

Directory of Open Access Journals (Sweden)

Fabiana G. Moreira

2001-03-01

Full Text Available The use of a methyl-D-glucoside (alphaMG, a synthetic analogue of maltose, as carbon source and inducer of amylase synthesis to several species of Aspergillus was studied in submerged and solid-state fermentations. Among a group of ten species, A. tamarii, A. fumigatus and A. flavus were able to produce biomass and high specific amylolytic activity in submerged cultures containing alphaMG as the only carbon source. In solid state fermentation, the enrichment of basal wheat bran or corn cob medium with alphaMG increased up to 3 times the production of amylases. In both submerged and solid state fermentations, alphaMG was more effective inducer of amylases than maltose and starch.

Ionizing radiation induced attachment reactions of nucleic acids and their components

International Nuclear Information System (INIS)

Myers, L.S. Jr.

1975-01-01

An extensive bibliographic review is given of experimental and theoretical data on radiation-induced attachment reactions of nucleic acids and their components. Mechanisms of these reactions are reviewed. The reactions with water, formate, and alcohols, with amines and other small molecules, and with radiation sensitizers and nucleic acid-nucleic acid reactions are discussed. Studies of the reaction mechanisms show that many of the reactions occur by radical-molecule reactions, but radical-radical reactions also occur. Radiation modifiers become attached to nucleic acids in vitro and in vivo and there are indications that attachment may be necessary for the action of some sensitizers. (U.S.)

Neutron-induced cross sections of actinides via the surrogate-reaction method

Directory of Open Access Journals (Sweden)

Ducasse Q.

2013-12-01

Full Text Available The surrogate-reaction method is an indirect way of determining cross sections for reactions that proceed through a compound nucleus. This technique may enable neutron-induced cross sections to be extracted for short-lived nuclei that otherwise cannot be measured. However, the validity of the surrogate method has to be investigated. In particular, the absence of a compound nucleus formation and the Jπ dependence of the decay probabilities may question the method. In this work we study the reactions 238U(d,p239U, 238U(3He,t238Np, 238U(3He,4He237U as surrogates for neutron-induced reactions on 238U, 237Np and 236U, respectively, for which good quality data exist. The experimental set-up enabled the measurement of fission and gamma-decay probabilities. The first results are hereby presented.

HLA-A*3101 and carbamazepine-induced hypersensitivity reactions in Europeans.

LENUS (Irish Health Repository)

McCormack, Mark

2011-03-24

Carbamazepine causes various forms of hypersensitivity reactions, ranging from maculopapular exanthema to severe blistering reactions. The HLA-B*1502 allele has been shown to be strongly correlated with carbamazepine-induced Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS-TEN) in the Han Chinese and other Asian populations but not in European populations.

NRABASE 2.0. Charged-particle nuclear reaction data for ion beam analysis

International Nuclear Information System (INIS)

Gurbich, A.F.

1997-01-01

For 30 targets between H-1 and Ag-109, differential cross sections for reactions induced by protons, deuterons, He-3 and alpha particles are given in tabular and graphical form. The data were compiled from original experimental references. The database was developed under a research contract with the IAEA Physics Section and is available on diskette from the IAEA Nuclear Data Section. (author)

The alpha channeling effect

Science.gov (United States)

Fisch, N. J.

2015-12-01

Alpha particles born through fusion reactions in a tokamak reactor tend to slow down on electrons, but that could take up to hundreds of milliseconds. Before that happens, the energy in these alpha particles can destabilize on collisionless timescales toroidal Alfven modes and other waves, in a way deleterious to energy confinement. However, it has been speculated that this energy might be instead be channeled into useful energy, so as to heat fuel ions or to drive current. Such a channeling needs to be catalyzed by waves Waves can produce diffusion in energy of the alpha particles in a way that is strictly coupled to diffusion in space. If these diffusion paths in energy-position space point from high energy in the center to low energy on the periphery, then alpha particles will be cooled while forced to the periphery. The energy from the alpha particles is absorbed by the wave. The amplified wave can then heat ions or drive current. This process or paradigm for extracting alpha particle energy collisionlessly has been called alpha channeling. While the effect is speculative, the upside potential for economical fusion is immense. The paradigm also operates more generally in other contexts of magnetically confined plasma.

Über die Reaktion von [alpha]- und [beta]-Tetralon mit Kaliumsuperoxid

OpenAIRE

Lissel, Manfred

1984-01-01

The reaction of [alpha]- and [beta]-tetralone with potassium superoxide is described. In addition to 2-hydroxy-1,4-naphthoquinone [alpha]-naphthol is formed from [alpha]-tetralone and [beta]-naphthol and 2-carboxy-benzenepropionic acid from [beta]-tetralone.

New concept for a wall detector for alpha particles

International Nuclear Information System (INIS)

Miley, G.H.; Kislev, H.; Micklich, B.J.

1985-01-01

A new concept for a wall-mounted detector is described here that would measure D-T alpha flux and corresponding pitch angle distribution in tokamaks (or related toroidal devices). The sensing element is a conical Micro Channel Ring (MCR) coated with 1 to 2μ of ZnS scintillator (or possibly ZnO). The collimation of the α particles is provided by two circumferential slots at the wall surface. The alpha scintillation events on the MCR are transferred through the ring channels and coupled fiber optics bundle to an external processor. From the magnetic field vector at a given point on the device wall, a certain relation can be set up between the α-induced scintillation position on the MCR and its original pitch angle (i.e., the angle between the α emission from the fusion reaction and the magnetic field vector) which is equal to the local pitch angle since the wall α flux is dominated by prompt losses

General applicability of chicken egg yolk antibodies: the performance of IgY immunoglobulins raised against the hypoxia-inducible factor 1alpha

OpenAIRE

Camenisch, G; Tini, M; Chilov, D; Kvietikova, I; Srinivas, V; Caro, J; Spielmann, P; Wenger, R H; Gassmann, M

1999-01-01

Avian embryos and neonates acquire passive immunity by transferring maternal immunoglobulins from serum to egg yolk. Despite being a convenient source of antibodies, egg yolk immunoglobulins (IgY) from immunized hens have so far received scant attention in research. Here we report the generation and rapid isolation of IgY from the egg yolk of hens immunized against the alpha subunit of the human hypoxia-inducible factor 1 (HIF-1alpha). Anti-HIF-1alpha IgY antibodies were affinity purified and...

Nonequilibrium photochemical reactions induced by lasers. Technical progress report

International Nuclear Information System (INIS)

Steinfeld, J.I.

1978-04-01

Research has progressed in six principal subject areas of interest to DOE advanced (laser) isotope separation efforts. These are (1) Infrared double resonance spectroscopy of molecules excited by multiple infrared photon absorption, particularly SF 6 and vinyl chloride. (2) Infrared multiphoton excitation of metastable triplet-state molecules, e.g., biacetyl. (3) An Information Theory analysis of multiphoton excitation and collisional deactivation has been carried out. (4) The mechanism of infrared energy deposition and multiphoton-induced reactions in chlorinated ethylene derivatives; and RRKM (statistical) model accounts for all observed behavior of the system, and a deuterium-specific reaction pathway has been identified. (5) Diffusion-enhanced laser isotope separation in N 16 O/N 18 O. (6) A technical evaluation of laser-induced chemistry and isotope separation

C-terminal cleavage of DeltaNp63alpha is associated with TSA-induced apoptosis in immortalized corneal epithelial cells.

Science.gov (United States)

Robertson, Danielle M; Ho, Su-Inn; Cavanagh, H Dwight

2010-08-01

In the central human corneal epithelium, loss of DeltaNp63 occurs in all surface epithelial cells preparing to undergo desquamation, suggesting a potential role for DeltaNp63 isoforms in mediating surface cell apoptotic shedding. In this study, the authors investigated a role for DeltaNp63 isoforms in caspase-mediated apoptosis in a telomerase-immortalized corneal epithelial cell line. For in vitro studies, hTCEpi cells were cultured in KGM-2 serum-free culture media containing 0.15 mM calcium. To assess dynamic protein interactions among individual DeltaNp63 isoforms, DeltaNp63-EGFP expression plasmids were transiently expressed in hTCEpi cells and evaluated by FRAP. Trichostatin-A (TSA; 3.31 muM) was used to induce cell death as measured by caspase activity. Cleavage and loss of endogenous DeltaNp63alpha, DeltaNp63-EGFP expression plasmids, and p53 were assessed after treatment with TSA and siRNA. Transient expression of DeltaNp63-EGFP alpha and beta isoforms resulted in the formation of a smaller isoform similar in size to DeltaNp63gamma-EGFP. FRAP demonstrated that DeltaNp63alpha-EGFP has greater immobile fraction than beta or gamma. TSA induced caspase-mediated apoptotic pathways; caspase induction was accompanied by a decrease in endogenous DeltaNp63alpha and p53. TSA upregulated DeltaNp63-EGFP plasmid expression; this was accompanied by a selective increase in cleavage of DeltaNp63alpha-EGFP. siRNA knockdown of DeltaNp63alpha correlated with a reduction in p53 independently of TSA. DeltaNp63alpha is the dominant active isoform in corneal epithelial cell nuclei. Loss of DeltaNp63alpha occurs during apoptotic signaling by cleavage at the C terminus. The corresponding loss of p53 suggests that a significant relationship appears to exist between these two regulatory proteins.

Connections between lepton-induced and hadron-induced multiparticle reactions

International Nuclear Information System (INIS)

Brodsky, S.J.; Gunion, J.F.

1976-01-01

Jet production is studied as a link between hadron- and lepton-induced reactions and interpreted in terms of models of underlying quark dynamics. We discuss how fragmentation distributions, quantum number flow, the charged-momentum vector, and quark counting rules can discriminate among various possible jet structures. We also review recent work on the possible relationship of the rising hadron multiplicity to quark confinement and color gauge theories. A number of new tests of quark models in hadron, photon, and lepton collisions are discussed. (orig.) [de

Nonelastic nuclear reactions induced by light ions with the BRIEFF code

CERN Document Server

Duarte, H

2010-01-01

The intranuclear cascade (INC) code BRIC has been extended to compute nonelastic reactions induced by light ions on target nuclei. In our approach the nucleons of the incident light ion move freely inside the mean potential of the ion in its center-of-mass frame while the center-of-mass of the ion obeys to equations of motion dependant on the mean nuclear+Coulomb potential of the target nucleus. After transformation of the positions and momenta of the nucleons of the ion into the target nucleus frame, the collision term between the nucleons of the target and of the ion is computed taking into account the partial or total breakup of the ion. For reactions induced by low binding energy systems like deuteron, the Coulomb breakup of the ion at the surface of the target nucleus is an important feature. Preliminary results of nucleon production in light ion induced reactions are presented and discussed.

Measurement of sup 15 O(. alpha. ,. gamma. ) sup 19 Ne resonance strengths

Energy Technology Data Exchange (ETDEWEB)

Magnus, P V; Smith, M S; Howard, A J; Parker, P D [Yale Univ., New Haven, CT (USA). Nuclear Structure Lab.; Champagne, A E [Princeton Univ., NJ (USA). Dept. of Physics

1990-01-08

States in {sup 19}Ne above the {sup 15}O+{alpha} threshold were populated by means of the {sup 19}F({sup 3}He,t){sup 19}Ne* reaction, and their alpha-particle decays to the {sup 15}O ground state were measured. The branching ratios {Gamma}{sub {alpha}}/{Gamma}{sub total} for the E{sub c.m.}=850-, 1020-, 1971-, 1183- and 1563-keV resonances in {sup 15}O+{alpha} were determined. This information together with alpha-particle and/or gamma-ray partial widths (determined from knowledge of these quantities for the mirror states in {sup 19}F) determines the strengths of these {sup 15}O({alpha},{gamma}){sup 19}Ne resonances and the {sup 15}O({alpha},{gamma}){sup 19}Ne reaction rate for temperatures between 7x10{sup 8} and 3x10{sup 9} K. (orig.).

Anti-TNF-alpha antibody attenuates subarachnoid hemorrhage-induced apoptosis in the hypothalamus by inhibiting the activation of Erk

Directory of Open Access Journals (Sweden)

Ma L

2018-02-01

Full Text Available Ling Ma,1 Yong Jiang,2 Yanan Dong,2 Jun Gao,2 Bin Du,2 Dianwei Liu2 1Department of Clinical Laboratory, The Second Hospital of Shandong University, Jinan, Shandong, People’s Republic of China; 2Department of Neurosurgery, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong, People’s Republic of China Background: Subarachnoid hemorrhage (SAH can induce apoptosis in many regions of the brain including the cortex and hippocampus. However, few studies have focused on apoptosis in the hypothalamus after SAH. Although some antiapoptotic strategies have been developed for SAH, such as anti-tumor necrosis factor-alpha (TNF-α antibody, the molecular mechanisms underlying this condition have yet to be elucidated. Therefore, the purpose of this study was to evaluate whether SAH could induce apoptosis in the hypothalamus and identify the potential molecular mechanisms underlying the actions of anti-TNF-α antibody, as a therapeutic regimen, upon apoptosis. Materials and methods: SAH was induced in a rat model. Thirty minutes prior to SAH, anti-TNF-α antibody or U0126, an extracellular signal-regulated kinase (Erk inhibitor, was microinjected into the left lateral cerebral ventricle. In addition, phorbol-12-myristate-13-acetate was injected intraperitoneally immediately after the anti-TNF-α antibody microinjection. Then, real-time polymerase chain reaction, Western blotting and immunohistochemistry were used to detect the expression of caspase-3, bax, bcl-2, phosphorylated Erk (p-Erk and Erk. Finally, anxiety-like behavior was identified by using open field. Results: Levels of caspase-3, bax and bcl-2, all showed a temporary rise after SAH in the hypothalamus, indicating the induction of apoptosis in this brain region. Interestingly, we found that the microinjection of anti-TNF-α antibody could selectively block the elevated levels of bax, suggesting the potential role of anti-TNF-α antibody in the inhibition of SAH-induced

Pre-equilibrium (exciton) model and the heavy-ion reactions with cluster emission

CERN Document Server

Betak, E

2015-01-01

We bring the possibility to include the cluster emission into the statistical pre-equilibrium (exciton) model enlarged for considering also the heavy ion collisions. At this moment, the calculations have been done without treatment of angular momentum variables, but all the approach can be straightforwardly applied to heavy-ion reactions with cluster emission including the angular momentum variables. The direct motivation of this paper is a possibility of producing the superdeformed nuclei, which are easier to be detected in heavy-ion reactions than in those induced by light projectiles (nucleons, deuterons, $\\alpha$-particles).

Secondary isotope effects on alpha-cleavage reactions

International Nuclear Information System (INIS)

Ingemann, S.; Hammerum, S.

1980-01-01

Kinetic deuterium isotope effects on mass spectral reactions have in several instances been utilized to provide structural information and to answer mechanistic questions. Typically, the influence of the deuterium label on the rate of one of a number of competing reactions has been studied. Secondary isotope effects have usually been assumed to be relatively insignificant in comparison with the observed kinetic effects, even though various workers have shown that secondary isotope effects may indeed exert a considerable influence on the rates of competing simple cleavages. Recent studies have provided quantitative data to show that the mere presence of deuterium atoms up to six bonds away may influence the rate of a simple cleavage reaction. In relation to an investigation of rearrangements accompanying simple cleavage reactions, a semi-quantitative measure was needed of the variation of the secondary isotope effect with the number of bonds between the deuterium label and the point of rupture. The influence has therefore been examined of the presence of remote deuterium atoms on a typical simple cleavage reaction, the α-cleavage of aliphatic amines. As a model compound, N-methyldipentylamine was chosen, systematically labelled with deuterium. (author)

alpha-MSH in systemic inflammation. Central and peripheral actions.

Science.gov (United States)

Catania, A; Delgado, R; Airaghi, L; Cutuli, M; Garofalo, L; Carlin, A; Demitri, M T; Lipton, J M

1999-10-20

Until recently, inflammation was believed to arise from events taking place exclusively in the periphery. However, it is now clear that central neurogenic influences can either enhance or modulate peripheral inflammation. Therefore, it should be possible to improve treatment of inflammation by use of antiinflammatory agents that reduce peripheral host responses and inhibit proinflammatory signals in the central nervous system (CNS). One such strategy could be based on alpha-melanocyte stimulating hormone (alpha-MSH). Increases in circulating TNF-alpha and nitric oxide (NO), induced by intraperitoneal administration of endotoxin in mice, were modulated by central injection of a small concentration of alpha-MSH. Inducible nitric oxide synthase (iNOS) activity and iNOS mRNA in lungs and liver were likewise modulated by central alpha-MSH. Increase in lung myeloperoxidase (MPO) activity was significantly less in lungs of mice treated with central alpha-MSH. Proinflammatory agents induced by endotoxin were significantly greater after blockade of central alpha-MSH. The results suggest that antiinflammatory influences of neural origin that are triggered by alpha-MSH could be used to treat systemic inflammation. In addition to its central influences, alpha-MSH has inhibitory effects on peripheral host cells, in which it reduces release of proinflammatory mediators. alpha-MSH reduces chemotaxis of human neutrophils and production of TNF-alpha, neopterin, and NO by monocytes. In research on septic patients, alpha-MSH inhibited release of TNF-alpha, interleukin-1 beta (IL-1 beta), and interleukin-8 (IL-8) in whole blood samples in vitro. Combined central and peripheral influences can be beneficial in treatment of sepsis.

Pressure effects on enzyme reactions in mainly organic media: alpha-chymotrypsin in reversed micelles of Aerosol OT in octane.

Science.gov (United States)

Mozhaev, V V; Bec, N; Balny, C

1994-08-01

Biocatalytic transformations in reversed micelles formed by anionic surfactant Aerosol OT in octane have been studied at high pressures by an example of alpha-chymotrypsin-catalyzed hydrolysis of N-carbobenzoxy-L-tyrosine p-nitrophenyl ester and N-succinyl-L-phenylalanine p-nitroanilide. For the first time it has been found that the enzyme retains high activity in these water-in-oil microemulsions up to a pressure of 2 kbar. The value of the activation volume (delta V*) for the enzyme reactions shows a dependence on the water content in the system. When the size of the micellar aqueous inner cavity (as evaluated at 1 atm) approaches the molecular size of alpha-chymotrypsin, delta V* becomes significantly different from the value in aqueous solution and in the micelles with a larger size. Possibilities of regulating the enzyme activity by pressure in systems with a low content of water are discussed.

Quantitative immuno-electron microscopic analysis of depolarization-induced expression of PGC-1alpha in cultured rat visual cortical neurons.

Science.gov (United States)

Meng, Hui; Liang, Huan Ling; Wong-Riley, Margaret

2007-10-17

Peroxisome proliferator-activated receptor-gamma coactivator 1alpha (PGC- 1alpha) is a coactivator of nuclear receptors and other transcription factors that regulate several metabolic processes, including mitochondrial biogenesis, energy homeostasis, respiration, and gluconeogenesis. PGC-1alpha plays a vital role in stimulating genes that are important to oxidative metabolism and other mitochondrial functions in brown adipose tissue and skeleton muscles, but the significance of PGC-1alpha in the brain remains elusive. The goal of our present study was to determine by means of quantitative immuno-electron microscopy the expression of PGC-1alpha in cultured rat visual cortical neurons under normal conditions as well as after depolarizing stimulation for varying periods of time. Our results showed that: (a) PGC-1alpha was normally located in both the nucleus and the cytoplasm. In the nucleus, PGC-1alpha was associated mainly with euchromatin rather than heterochromatin, consistent with active involvement in transcription. In the cytoplasm, it was associated mainly with free ribosomes. (b) Neuronal depolarization by KCl for 0.5 h induced a significant increase in PGC-1alpha labeling density in both the nucleus and the cytoplasm (Pneuronal activity by synthesizing more proteins in the cytoplasm and translocating them to the nucleus for gene activation. PGC-1alpha level in neurons is, therefore, tightly regulated by neuronal activity.

Production and measurement of dispersion aerosols; application to the transport of deuteron-induced and 84Kr-induced reaction recoils

International Nuclear Information System (INIS)

Schmidt-Ott, W.-D.; Dincklage, R.-D. von

1977-01-01

Dispersion aerosols were produced from various fluids and mixed with helium, nitrogen, and air. The diameter of the aerosols was estimated from their deflection in a low density micro-jet. These two-phase flows were tested for their transport performance for recoils of deuteron-induced reactions at the Goettingen cyclotron. Transport yields of 70%, 90% and 86% were measured when using n-decane with helium, nitrogen, and air, respectively. In comparison to the earlier use of ethylene the amount of disturbing activity induced on the gases was much smaller. The effect of aerosol formation by condensation is discussed. The system was applied in electron- and γ-ray spectroscopy of deuteron-induced reaction recoils. The mixture of n-decane and helium was used for the transport of 84 Kr-induced reaction recoils at the Darmstadt UNILAC. (Auth.)

Enantioselective cycloadditions with alpha,beta-disubstituted acrylimides.

Science.gov (United States)

Sibi, Mukund P; Ma, Zhihua; Itoh, Kennosuke; Prabagaran, Narayanasamy; Jasperse, Craig P

2005-06-09

[reaction: see text] The use of N-H imide templates provides a solution to the problem of rotamer control in Lewis acid catalyzed reactions of alpha,beta-disubstituted acryloyl imides. Reactions proceed through the s-cis rotamer and with improved reactivity because A(1,3) strain is avoided. Enantioselective nitrone, nitrile oxide, and Diels-Alder cycloadditions demonstrate the principle.

HSP72 protects cells from ER stress-induced apoptosis via enhancement of IRE1alpha-XBP1 signaling through a physical interaction.

LENUS (Irish Health Repository)

Gupta, Sanjeev

2010-01-01

Endoplasmic reticulum (ER) stress is a feature of secretory cells and of many diseases including cancer, neurodegeneration, and diabetes. Adaptation to ER stress depends on the activation of a signal transduction pathway known as the unfolded protein response (UPR). Enhanced expression of Hsp72 has been shown to reduce tissue injury in response to stress stimuli and improve cell survival in experimental models of stroke, sepsis, renal failure, and myocardial ischemia. Hsp72 inhibits several features of the intrinsic apoptotic pathway. However, the molecular mechanisms by which Hsp72 expression inhibits ER stress-induced apoptosis are not clearly understood. Here we show that Hsp72 enhances cell survival under ER stress conditions. The UPR signals through the sensor IRE1alpha, which controls the splicing of the mRNA encoding the transcription factor XBP1. We show that Hsp72 enhances XBP1 mRNA splicing and expression of its target genes, associated with attenuated apoptosis under ER stress conditions. Inhibition of XBP1 mRNA splicing either by dominant negative IRE1alpha or by knocking down XBP1 specifically abrogated the inhibition of ER stress-induced apoptosis by Hsp72. Regulation of the UPR was associated with the formation of a stable protein complex between Hsp72 and the cytosolic domain of IRE1alpha. Finally, Hsp72 enhanced the RNase activity of recombinant IRE1alpha in vitro, suggesting a direct regulation. Our data show that binding of Hsp72 to IRE1alpha enhances IRE1alpha\\/XBP1 signaling at the ER and inhibits ER stress-induced apoptosis. These results provide a physical connection between cytosolic chaperones and the ER stress response.

Analyses of Alpha-Alpha Elastic Scattering Data in the Energy Range 140 - 280 MeV

Energy Technology Data Exchange (ETDEWEB)

Shehadeh, Zuhair F. [Taif University, Taif (Saudi Arabia)

2017-01-15

The differential and the reaction cross-sections for 4He-4He elastic scattering data have been nicely obtained at four energies ranging from 140 MeV to 280 MeV (lab system), namely, 140, 160, 198 and 280 MeV, by using a new optical potential with a short-range repulsive core. The treatment has been handled relativistically as υ/c > 0.25 for the two lower energies and υ/c > 0.31 for the two higher ones. In addition to explaining the elastic angular distributions, the adopted potentials accounted for the structure that may exist at angles close to 90◦ , especially for the 198 and the 280-MeV incident energies. No renormalization has been used, and all our potential parameters are new. The necessity of including a short-range repulsive potential term in our real nuclear potential part has been demonstrated. Our results contribute to solving a long-standing problem concerning the nature of the alpha-alpha potential. This is very beneficial in explaining unknown alpha-nucleus and nucleus-nucleus relativistic reactions by using the cluster formalism.

Nitric oxide mediated DNA double strand breaks induced in proliferating bystander cells after {alpha}-particle irradiation

Energy Technology Data Exchange (ETDEWEB)

Han Wei [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong); Chen Shaopeng [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong); Key Laboratory of Ion Beam Bioengineering, Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Yu, K.N., E-mail: peter.yu@cityu.edu.hk [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong); Wu Lijun [Key Laboratory of Ion Beam Bioengineering, Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)

2010-02-03

Low-dose {alpha}-particle exposures comprise 55% of the environmental dose to the human population and have been shown to induce bystander responses. Previous studies showed that bystander effect could induce stimulated cell growth or genotoxicity, such as excessive DNA double strand breaks (DSBs), micronuclei (MN), mutation and decreased cell viability, in the bystander cell population. In the present study, the stimulated cell growth, detected with flow cytometry (FCM), and the increased MN and DSB, detected with p53 binding protein 1 (53BP1) immunofluorescence, were observed simultaneously in the bystander cell population, which were co-cultured with cells irradiated by low-dose {alpha}-particles (1-10 cGy) in a mixed system. Further studies indicated that nitric oxide (NO) and transforming growth factor {beta}1 (TGF-{beta}1) played very important roles in mediating cell proliferation and inducing MN and DSB in the bystander population through treatments with NO scavenger and TGF-{beta}1 antibody. Low-concentrations of NO, generated by spermidine, were proved to induce cell proliferation, DSB and MN simultaneously. The proliferation or shortened cell cycle in bystander cells gave them insufficient time to repair DSBs. The increased cell division might increase the probability of carcinogenesis in bystander cells since cell proliferation increased the probability of mutation from the mis-repaired or un-repaired DSBs.

Adverse drug reactions induced by cardiovascular drugs in outpatients

Directory of Open Access Journals (Sweden)

Gholami K

2008-03-01

Full Text Available Considering increased use of cardiovascular drugs and limitations in pre-marketing trials for drug safety evaluation, post marketing evaluation of adverse drug reactions (ADRs induced by this class of medicinal products seems necessary.Objectives: To determine the rate and seriousness of adverse reactions induced by cardiovascular drugs in outpatients. To compare sex and different age groups in developing ADRs with cardiovascular agents. To assess the relationship between frequencies of ADRs and the number of drugs used. Methods: This cross-sectional study was done in cardiovascular clinic at a teaching hospital. All patients during an eight months period were evaluated for cardiovascular drugs induced ADRs. Patient and reaction factors were analyzed in detected ADRs. Patients with or without ADRs were compared in sex and age by using chi-square test. Assessing the relationship between frequencies of ADRs and the number of drugs used was done by using Pearson analysis. Results: The total number of 518 patients was visited at the clinic. ADRs were detected in 105 (20.3% patients. The most frequent ADRs were occurred in the age group of 51-60. The highest rate of ADRs was recorded to be induced by Diltiazem (23.5% and the lowest rate with Atenolol (3%. Headache was the most frequent detected ADR (23%. Assessing the severity and preventability of ADRs revealed that 1.1% of ADRs were detected as severe and 1.9% as preventable reactions. Women significantly developed more ADRs in this study (chi square = 3.978, P<0.05. ADRs more frequently occurred with increasing age in this study (chi square = 15.871, P<0.05. With increasing the number of drugs used, the frequency of ADRs increased (Pearson=0.259, P<0.05. Conclusion: Monitoring ADRs in patients using cardiovascular drugs is a matter of importance since this class of medicines is usually used by elderly patients with critical conditions and underlying diseases.

Equine colostral carbohydrates reduce lipopolysaccharide-induced inflammatory responses in equine peripheral blood mononuclear cells.

Science.gov (United States)

Vendrig, J C; Coffeng, L E; Fink-Gremmels, J

2012-12-01

Increasing evidence suggests that reactions to lipopolysaccharide (LPS), particularly in the gut, can be partly or completely mitigated by colostrum- and milk-derived oligosaccharides. Confirmation of this hypothesis could lead to the development of new therapeutic concepts. To demonstrate the influence of equine colostral carbohydrates on the inflammatory response in an in vitro model with equine peripheral blood mononuclear cells (PBMCs). Carbohydrates were extracted from mare colostrum, and then evaluated for their influence on LPS-induced inflammatory responses in PBMCs isolated from the same mares, mRNA expression of tumour necrosis factor-alpha, interleukin-6 and interleukin-10 was measured as well as the protein levels of tumour necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10). Equine colostral carbohydrates significantly reduced LPS-induced TNF-alpha protein at both times measured and significantly reduced LPS-induced TNF-alpha, IL-6 and IL-10 mRNA expression by PBMCs. Moreover, cell viability significantly increased in the presence of high concentrations of colostral carbohydrates. Carbohydrates derived from equine colostrum reduce LPS-induced inflammatory responses of equine PBMCs. Colostrum and milk-derived carbohydrates are promising candidates for new concepts in preventive and regenerative medicine.

Chemical reactions induced and probed by positive muons

International Nuclear Information System (INIS)

Ito, Yasuo

1990-01-01

The application of μ + science, collectively called μSR, but encompassing a variety of methods including muon spin rotation, muon spin relaxation, muon spin repolarization, muon spin resonance and level-crossing resonance, to chemistry is introduced emphasizing the special aspects of processes which are 'induced and probed' by the μ + itself. After giving a general introduction to the nature and methods of muon science and a short history of muon chemistry, selected topics are given. One concerns the usefulness of muonium as hydrogen-like probes of chemical reactions taking polymerization of vinyl monomers and reaction with thiosulphate as examples. Probing solitons in polyacetylene induced and probed by μ + is also an important example which shows the unique nature of muonium. Another important topic is 'lost polarization'. Although this term is particular to muonium. Another important topic is 'lost polarization'. Although this term is particular to muon chemistry, the chemistry underlining the phenomenon of lost polarization has an importance to both radiation and hot atom chemistries. (orig.)

Noise-and delay-induced phase transitions of the dimer–monomer surface reaction model

International Nuclear Information System (INIS)

Zeng Chunhua; Wang Hua

2012-01-01

Highlights: ► We study the dimer–monomer surface reaction model. ► We show that noise induces first-order irreversible phase transition (IPT). ► Combination of noise and time-delayed feedback induce first- and second-order IPT. ► First- and second-order IPT is viewed as noise-and delay-induced phase transitions. - Abstract: The effects of noise and time-delayed feedback in the dimer–monomer (DM) surface reaction model are investigated. Applying small delay approximation, we construct a stochastic delayed differential equation and its Fokker–Planck equation to describe the state evolution of the DM reaction model. We show that the noise can only induce first-order irreversible phase transition (IPT) characteristic of the DM model, however the combination of the noise and time-delayed feedback can simultaneously induce first- and second-order IPT characteristics of the DM model. Therefore, it is shown that the well-known first- and second-order IPT characteristics of the DM model may be viewed as noise-and delay-induced phase transitions.

Expression of hypoxia-inducible factor 1 alpha and its downstream targets in fibroepithelial tumors of the breast

NARCIS (Netherlands)

Kuijper, Arno; Groep, P. van der; Wall, E. van der; Diest, P.J. van

2005-01-01

INTRODUCTION Hypoxia-inducible factor 1 (HIF-1) alpha and its downstream targets carbonic anhydrase IX (CAIX) and vascular endothelial growth factor (VEGF) are key factors in the survival of proliferating tumor cells in a hypoxic microenvironment. We studied the expression and prognostic relevance

Suppressor of cytokine signalling-3 inhibits Tumor necrosis factor-alpha induced apoptosis and signalling in beta cells

DEFF Research Database (Denmark)

Bruun, Christine; Heding, Peter E; Rønn, Sif G

2009-01-01

Tumor necrosis factor-alpha (TNFalpha) is a pro-inflammatory cytokine involved in the pathogenesis of several diseases including type 1 diabetes mellitus (T1DM). TNFalpha in combination with interleukin-1-beta (IL-1beta) and/or interferon-gamma (IFNgamma) induces specific destruction...

Alpha Resonant States in 13C

International Nuclear Information System (INIS)

Rodrigues, M. R. D.; Borello-Lewin, T.; Horodynski-Matsushigue, L. B.; Duarte, J. L. M.; Rodrigues, C. L.; Souza, M. A.; Miyake, H.; Cunsolo, A.; Cappuzzello, F.; Ukita, G. M.

2011-01-01

The 9 Be( 6 Li,d) 13 C reaction was used to investigate alpha resonant states in 13 C up to 15 MeV of excitation. The reaction was measured at a bombarding energy of 25.5 MeV employing the Sao Paulo Pelletron-Enge-Spectrograph facility and the nuclear emulsion detection technique. An energy resolution of 50 keV was obtained. Several narrow alpha resonant states not previously measured were detected, in particular the one at the (3α+n) threshold populated by an L = 2 transfer, revealing a 9 Be+α component for the 1/2 - cluster state candidate at this threshold. Experimental angular distributions are presented in comparison with DWBA predictions.

Partial equilibrium in induced redox reactions of plutonium

Energy Technology Data Exchange (ETDEWEB)

Nikol' skii, B P; Posvol' skii, M V; Krylov, L I; Morozova, Z P

1975-01-01

A study was made of oxidation-reduction reactions of Pu in buffer solutions containing bichromate and a reducing agent which reacted with hexavalent chromium at pH=3.5. In most cases sodium nitrite was used. A rather slow reduction of Pu (6) with NaNO/sub 2/ in the course of which tetravalent plutonium was formed via disproportionation reaction of plutonium (5), became very rapid upon the addition of bichromate to the solution. The yield of tetravalent plutonium increased with an increase in the concentration of NaNO/sub 2/ and the bichromate but never reached 100%. This was due to a simultaneous occurrenc of the induced oxidation reaction of Pu(4), leading to a partial equilibrium between the valence forms of plutonium in the nitrite-bichromate system which on the whole was in a nonequilibrium state. It was shown that in the series of reactions leading to the reduction of plutonium the presence of bivalent chromium was a necessary link.

Contribution of alpha- and beta-defensins to lung function decline and infection in smokers: an association study

Directory of Open Access Journals (Sweden)

Anthonisen Nicholas R

2006-05-01

Full Text Available Abstract Background Alpha-defensins, which are major constituents of neutrophil azurophilic granules, and beta-defensins, which are expressed in airway epithelial cells, could contribute to the pathogenesis of chronic obstructive pulmonary disease by amplifying cigarette smoke-induced and infection-induced inflammatory reactions leading to lung injury. In Japanese and Chinese populations, two different beta-defensin-1 polymorphisms have been associated with chronic obstructive pulmonary disease phenotypes. We conducted population-based association studies to test whether alpha-defensin and beta-defensin polymorphisms influenced smokers' susceptibility to lung function decline and susceptibility to lower respiratory infection in two groups of white participants in the Lung Health Study (275 = fast decline in lung function and 304 = no decline in lung function. Methods Subjects were genotyped for the alpha-defensin-1/alpha-defensin-3 copy number polymorphism and four beta-defensin-1 polymorphisms (G-20A, C-44G, G-52A and Val38Ile. Results There were no associations between individual polymorphisms or imputed haplotypes and rate of decline in lung function or susceptibility to infection. Conclusion These findings suggest that, in a white population, the defensin polymorphisms tested may not be of importance in determining who develops abnormally rapid lung function decline or is susceptible to developing lower respiratory infections.

Cross sections of the reaction Pa-231(d,3n)U-230 for the production of U-230/Th-226 for targeted alpha therapy

Czech Academy of Sciences Publication Activity Database

Morgenstern, A.; Lebeda, Ondřej; Štursa, Jan; Capote, R.; Sin, M.; Bruchertseifer, F.; Zielinska, B.; Apostolidis, C.

2009-01-01

Roč. 80, č. 5 (2009), 054612/1-054612/6 ISSN 0556-2813 Institutional research plan: CEZ:AV0Z10480505 Keywords : Pa-231 * U-230 * Th-226 * reaction cross section * targeted alpha therapy Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 3.477, year: 2009

Apoptosis of murine melanoma B16-BL6 cells induced by quercetin targeting mitochondria, inhibiting expression of PKC-alpha and translocating PKC-delta.

Science.gov (United States)

Zhang, Xian-Ming; Chen, Jia; Xia, Yu-Gui; Xu, Qiang

2005-03-01

In our previous study, quercetin was found to induce apoptosis of murine melanoma B16-BL6 cells. The cellular and molecular mechanism of quercetin-induced apoptosis was investigated in the present study. Nuclear morphology was determined by fluorescence microscopy. DNA fragmentation was analyzed by electrophoresis and quantified by the diphenylamine method. The transmembrane potential of mitochondria was measured by flow cytometry. Bcl-2, Bcl-X(L), PKC-alpha, PKC-beta, and PKC-delta were detected by Western blotting. Caspase activity was determined spectrophotometrically. Quercetin induced the condensation of nuclei of B16-BL6 cells in a dose-dependent pattern as visualized by Hoechst 33258 and propidium iodide dying. Phorbol 12-myristate 13-acetate (PMA), a PKC activator, significantly enhanced apoptosis induced by quercetin, while doxorubicin, a PKC inhibitor, markedly decreased it. Both PMA and doxorubicin showed a consistent effect on the fragmentation of nuclear DNA caused by various dosages of quercetin. Quercetin dose-dependently led to loss of the mitochondrial membrane potential, which was also significantly reinforced or antagonized by PMA and doxorubicin, respectively. Moreover, PMA showed reinforcement, while doxorubicin showed significant antagonization, of the quercetin-mediated decrease in the expression of Bcl-2. Quercetin promoted caspase-3 activity in a dose-dependent manner, which was also regulated by PMA and doxorubicin with a pattern similar to that seen in their effect on apoptosis, mitochondrial membrane potential and Bcl-2 expression, but none of these were directly affected by PMA and doxorubicin. Free fatty acid and chlorpromazine, a PKC activator and inhibitor, respectively, did not interfere with these effects of quercetin. B16-BL6 cells expressed PKC-alpha, PKC-beta, and PKC-delta. Quercetin dose-dependently inhibited the expression of PKC-alpha but not that of PKC-beta and PKC-delta. Doxorubicin almost completely blocked the effect of

Nuclear dynamics in heavy ion induced fusion-fission reactions

International Nuclear Information System (INIS)

Kapoor, S.S.

1992-01-01

Heavy ion induced fission and fission-like reactions evolve through a complex nuclear dynamics encountered in the medium energy nucleus-nucleus collisions. In the recent years, measurements of the fragment-neutron and fragment-charged particle angular correlations in heavy ion induced fusion-fission reactions, have provided new information on the dynamical times of nuclear deformations of the initial dinuclear complex to the fission saddle point and the scission point. From the studies of fragment angular distributions in heavy ion induced fission it has been possible to infer the relaxation times of the dinuclear complex in the K-degree of freedom and our recent measurements on the entrance channel dependence of fragment anisotropies have provided an experimental signature of the presence of fissions before K-equilibration. This paper reviews recent experimental and theoretical status of the above studies with particular regard to the questions relating to dynamical times, nuclear dissipation and the effect of nuclear dissipation on the K-distributions at the fission saddle in completely equilibrated compound nucleus. (author). 19 refs., 9 figs

Additional evaluation of alpha induced neutron production nuclear data. 9Be, 27Al, 28,29,30Si

International Nuclear Information System (INIS)

Murata, Toru; Shibata, Keiichi

2005-01-01

Alpha particle induced neutron production cross sections, emitted neutron energy spectrum and angular distributions were evaluated for the target nucleus 9 Be, 27 Al and Si isotopes; 28 Si, 29 Si and 30 Si in the incident energy region below 15 MeV. (author)

Angular correlation measurements for 4-{alpha} decaying states in {sup 16}O

Energy Technology Data Exchange (ETDEWEB)

Wuosmaa, A.H.; Back, B.B.; Betts, R.R. [and others

1995-08-01

Previous measurements of the {sup 12}C({sup 12}C,{sup 8}Be){sup 16}O{sup *}(4 {alpha}) reaction identified discrete levels in {sup 16}O which decay by breakup into 4 {alpha} particles through a number of different decay sequences, including {sup 16}O{sup *} {yields} {sup 8}Be + {sup 8}Be and {alpha} + {sup 12}C (O{sub 2}{sup +}). These states are observed in a range of excitation energies where resonances are observed in inelastic {alpha} + {sup 12}C scattering leading to the {sup 8}Be + {sup 8}Be and {alpha} + {sup 12}C final states. These resonances were associated with 4 {alpha}-particle chain configurations in {sup 16}O. Should the states populated in the {sup 12}C + {sup 12}C reaction possess this same extended structure, it would serve as an important piece of evidence supporting the idea that even more deformed structures are formed in the {sup 24}Mg compound system. In order to more firmly make this association, it is important to determine the spins of the states populated in the {sup 12}C + {sup 12}C reaction.

HSP72 protects cells from ER stress-induced apoptosis via enhancement of IRE1alpha-XBP1 signaling through a physical interaction.

Directory of Open Access Journals (Sweden)

Sanjeev Gupta

2010-07-01

Full Text Available Endoplasmic reticulum (ER stress is a feature of secretory cells and of many diseases including cancer, neurodegeneration, and diabetes. Adaptation to ER stress depends on the activation of a signal transduction pathway known as the unfolded protein response (UPR. Enhanced expression of Hsp72 has been shown to reduce tissue injury in response to stress stimuli and improve cell survival in experimental models of stroke, sepsis, renal failure, and myocardial ischemia. Hsp72 inhibits several features of the intrinsic apoptotic pathway. However, the molecular mechanisms by which Hsp72 expression inhibits ER stress-induced apoptosis are not clearly understood. Here we show that Hsp72 enhances cell survival under ER stress conditions. The UPR signals through the sensor IRE1alpha, which controls the splicing of the mRNA encoding the transcription factor XBP1. We show that Hsp72 enhances XBP1 mRNA splicing and expression of its target genes, associated with attenuated apoptosis under ER stress conditions. Inhibition of XBP1 mRNA splicing either by dominant negative IRE1alpha or by knocking down XBP1 specifically abrogated the inhibition of ER stress-induced apoptosis by Hsp72. Regulation of the UPR was associated with the formation of a stable protein complex between Hsp72 and the cytosolic domain of IRE1alpha. Finally, Hsp72 enhanced the RNase activity of recombinant IRE1alpha in vitro, suggesting a direct regulation. Our data show that binding of Hsp72 to IRE1alpha enhances IRE1alpha/XBP1 signaling at the ER and inhibits ER stress-induced apoptosis. These results provide a physical connection between cytosolic chaperones and the ER stress response.

Reoxygenation of human coronary smooth muscle cells suppresses HIF-1{alpha} gene expression and augments radiation-induced growth delay and apoptosis

Energy Technology Data Exchange (ETDEWEB)

Grumann, T.; Arab, A.; Bode, C.; Hehrlein, C. [Dept. of Cardiology, Univ. Clinic of Freiburg (Germany); Guttenberger, R. [Dept. of Radiotherapy, Univ. Clinic of Freiburg (Germany)

2006-01-01

Background and Purpose: Catheter-based coronary brachytherapy with {beta}- and {gamma}-radiation is an evidence-based method to prevent restenosis after percutaneous transluminal coronary angioplasty (PTCA) and stent implantation, but the outcome may be PTCA are hypoxic. A lack of oxygen decreases the effect of low LET (linear energy transfer) irradiation. The authors assumed that reoxygenation of hypoxic human coronary smooth muscle cells (HCSMCs) improves the results of coronary brachytherapy. The expression of hypoxia-inducible factor 1{alpha} (HIF-1{alpha}) gene, and the rates of growth and apoptosis of hypoxic and reoxygenated HCSMCs after {gamma}-iradiation were therefore analyzed. Material and Methods: An in vitro model of megacolonies of HCSMCs was developed. After exposure to chronic hypoxia the HCSMCs were irradiated with graded doses of 2, 4, 8, and 16 Gy using a {sup 60}Co source either under hypoxia (pO{sub 2}<3 mmHg) or after reoxygenation (pO{sub 2}{approx}150 mmHg). RT-PCR (reverse transcription-polymerase chain reaction) analysis was used to quantify HIF-1{alpha} gene expression and the growth of HCSMC megacolonies was measured serially. The oxygen enhancement ratio (OER) was calculate from the specific growth delay. Apoptosis of HCSMCs was quantified by counting cells with specific DNA strand breaks using the TUNEL assy. Results: HIF-1{alpha} gene expression was markedly suppressed in reoxygenated cells versus hypoxic cells 30 min after {gamma}-irradiation at all radiation doses (158{+-}46% vs. 1,675{+-}1,211%; p<0.01). Apoptosis was markedly increased in reoxygenated HCSMCs. The OER was 1.8(95% CI[confidence interval]1.3-2.4). Therefore, reoxygenated HCSMCs require 44% less radiation dose to achieve the equivalent biological radiation effect compared to hypoxic HCSMCs. Conclusion: Reoxygenation of coronary smooth muscle cells should be considered an option to increase efficacy of coronary brachytherapy. This could be used to reduce radiation dose

Strain-induced structural changes and chemical reactions. 1: Thermomechanical and kinetic models

International Nuclear Information System (INIS)

Levitas, V.I.; Nesterenko, V.F.; Meyers, M.A.

1998-01-01

Strain-induced chemical reactions were observed recently (Nesterenko et al) in experiments in the shear band in both Ti-Si and Nb-Si mixtures. Reactions can start in the solid state or after melting of at least one component. One of the aims is to find theoretically whether there are possible macroscopic mechanisms of mechanical intensification of the above and other chemical reactions due to plastic shear in the solid state. Continuum thermodynamical theory of structural changes with an athermal kinetics, which includes martensitic phase transformations, plastic strain-induced chemical reactions and polymorphic transformations, is developed at finite strains. The theory includes kinematics, criterion of structural change and extremum principle for determination of all unknown variable parameters for the case with neglected elastic strains. Thermodynamically consistent kinetic theory of thermally activated structural changes is suggested. The concept of the effective temperature is introduced which takes into account that temperature can vary significantly (on 1,000 K) during the chemical reactions under consideration. The theory will be applied in Part 2 of the paper for the description of chemical reactions in the shear band

Adrenergic stimulation promotes T-wave alternans and arrhythmia inducibility in a TNF-alpha genetic mouse model of congestive heart failure.

Science.gov (United States)

Shusterman, Vladimir; McTiernan, Charles F; Goldberg, Anna; Saba, Samir; Salama, Guy; London, Barry

2010-02-01

T-wave alternans (TWA) is a proarrhythmic repolarization instability that is common in congestive heart failure (CHF). Although transgenic mice are commonly used to study the mechanisms of arrhythmogenesis in CHF, little is known about the dynamics of TWA in these species. We hypothesized that TWA is present in a TNF-alpha model of CHF and can be further promoted by adrenergic stimulation. We studied 16 TNF-alpha mice and 12 FVB controls using 1) in vivo intracardiac electrophysiological testing and 2) ambulatory telemetry during 30 min before and after an intraperitoneal injection of isoproterenol. TWA was examined using both linear and nonlinear filtering applied in the time domain. In addition, changes in the mean amplitude of the T wave and area under the T wave were computed. During intracardiac electrophysiological testing, none of the animals had TWA or inducible arrhythmias before the injection of isoproterenol. After the injection, sustained TWA and inducible ventricular tachyarrhythmias were observed in TNF-alpha mice but not in FVB mice. In ambulatory telemetry, before the isoproterenol injection, the cardiac cycle length (CL) was longer in TNF-alpha mice than in FVB mice (98 +/- 9 and 88 +/- 3 ms, P = 0.04). After the injection of isoproterenol, the CL became 8% and 6% shorter in TNF-alpha and FVB mice (P mice, the magnitude of TWA was 1.5-2 times greater than in FVB mice both before and after the isoproterenol injection. The magnitude of TWA increased significantly after the isoproterenol injection compared with the baseline in TNF-alpha mice (P = 0.003) but not in FVB mice. The mean amplitude of the T wave and area under the T wave increased 60% and 80% in FVB mice (P = 0.006 and 0.009) but not in TNF-alpha mice. In conclusion, TWA is present in a TNF-alpha model of CHF and can be further promoted by adrenergic stimulation, along with the enhanced susceptibility for ventricular arrhythmias.

Neutron-induced reactions on U and Th - A new approach via AMS

International Nuclear Information System (INIS)

Wallner, A.; Capote, R.; Christl, M.; Fifield, L.K.; Srncik, M.; Tims, S.; Hotchkis, M.; Krasa, A.; Lachner, J.; Lippold, J.; Plompen, A.; Semkova, V.; Steier, P.; Winkler, S.

2014-01-01

Recent studies exhibit discrepancies at keV and MeV energies between major nuclear data libraries for 238 U(n,γ), 232 Th(n,γ) and also for (n,xn) reactions. We have extended our initial (n,γ) measurements on 235,238 U to higher neutron energies and to additional reaction channels. Neutron-induced reactions on 232 Th and 238 U were measured by a combination of the activation technique and atom counting of the reaction products using accelerator mass spectrometry (AMS). Natural thorium and uranium samples were activated with quasi-monoenergetic neutrons at IRMM. Neutron capture data were produced for neutron energies between 0.5 and 5 MeV. Fast neutron-induced reactions were studied in the energy range from 17 to 22 MeV. Preliminary data indicate a fair agreement with data libraries; however at the lower band of existing data. This approach represents a complementary method to on-line particle detection techniques and also to conventional decay counting. (authors)

The water avoidance stress induces bladder pain due to a prolonged alpha1A adrenoceptor stimulation.

Science.gov (United States)

Matos, Rita; Serrão, Paula; Rodriguez, Larissa; Birder, Lori Ann; Cruz, Francisco; Charrua, Ana

2017-08-01

Bladder Pain Syndrome/Interstitial Cystitis (BPS/IC) remains an elusive disease with the cause for the pain unclear. BPS/IC patients present increased sympathetic activity and high levels of urinary noradrenaline. At the experimental level, it has been shown that chronic adrenergic stimulation produces pain and bladder changes through an alpha 1A adrenoceptor mediated mechanism. Water avoidance stress (WAS) in rodents reproduces signs of nociception and bladder changes seen in BPS/IC patients. In this study, we explore the possible role of alpha 1A adrenoceptor in bladder pain and morphological changes. WAS was induced in a group of female Wistar rats. A separate WAS group received 0.2 mg/kg day silodosin (WAS + S). Lower abdominal pain was determined by performing sensitivity to Von Frey filaments. Bladder reflex activity was determined by cystometry in anaesthetised animals. Urine was collected for noradrenaline quantification by HPLC. Bladders were harvested and stained with Haematoxylin-eosin (to analyse urothelial morphology and to determine the disruption of surface umbrella cells) or with Toluidine Blue 0.1% to analyse mast cell infiltration. WAS increased urinary noradrenaline level and bladder frequency and decreased mechanical pain threshold, which was reversed by silodosin. WAS induced lymphocytic and mast cells infiltration in the mucosa and mild urothelial disruption, which was absent in WAS + S group. Alpha 1A adrenoceptor stimulation has an important role in the appearance of bladder pain in rats. Since BPS/IC patients present high levels of noradrenaline, alpha 1A stimulation may be an additional trigger for bladder dysfunction presented by these patients. Further studies will determine the clinical relevance of this finding in the treatment of BPS/IC patients.

Production of interleukin-1alpha by human endometrial stromal cells is triggered during menses and dysfunctional bleeding and is induced in culture by epithelial interleukin-1alpha released upon ovarian steroids withdrawal.

Science.gov (United States)

Pretto, Chrystel M; Gaide Chevronnay, Héloïse P; Cornet, Patricia B; Galant, Christine; Delvaux, Denis; Courtoy, Pierre J; Marbaix, Etienne; Henriet, Patrick

2008-10-01

Endometrial breakdown during menstruation and dysfunctional bleeding is triggered by the abrupt expression of matrix metalloproteinases (MMPs), including interstitial collagenase (MMP-1). The paracrine induction of MMP-1 in stromal cells via epithelium-derived IL-1alpha is repressed by ovarian steroids. However, the control by estradiol (E) and progesterone (P) of endometrial IL-1alpha expression and bioactivity remains unknown. Variations of endometrial IL-1alpha mRNA and protein along the menstrual cycle and during dysfunctional bleeding were determined using RT-PCR, in situ hybridization, and immunolabeling. The mechanism of EP control was analyzed using culture of explants, laser capture microdissection, and purified cells. Data were compared with expression changes of IL-1beta and IL-1 receptor antagonist. IL-1alpha is synthesized by epithelial cells throughout the cycle but E and/or P prevents its release. In contrast, endometrial stromal cells produce IL-1alpha only at menses and during irregular bleeding in areas of tissue breakdown. Stromal expression of IL-1alpha, like that of MMP-1, is repressed by P (alone or with E) but triggered by epithelium-derived IL-1alpha released upon EP withdrawal. Our experiments in cultured endometrium suggest that IL-1alpha released by epithelial cells triggers the production of IL-1alpha by stromal cells in a paracrine amplification loop to induce MMP-1 expression during menstruation and dysfunctional bleeding. All three steps of this amplification cascade are repressed by EP.

Differential involvement of 5-HT(1A) and 5-HT(1B/1D) receptors in human interferon-alpha-induced immobility in the mouse forced swimming test.

Science.gov (United States)

Zhang, Hongmei; Wang, Wei; Jiang, Zhenzhou; Shang, Jing; Zhang, Luyong

2010-01-01

Although Interferon-alpha (IFN-alpha, CAS 9008-11-1) is a powerful drug in treating several viral infections and certain tumors, a considerable amount of neuropsychiatric side-effects such as depression and anxiety are an unavoidable consequence. Combination with the selective serotonin (5-HT) reuptake inhibitor (SSRI) fluoxetine (CAS 56296-78-7) significantly improved the situation. However, the potential 5-HT(1A) receptor- and 5-HT(1B) receptor-signals involved in the antidepressant effects are still unclear. The effects of 5-HT(1A) receptor- and 5-HT(1B) receptor signals were analyzed by using the mouse forced swimming test (FST), a predictive test of antidepressant-like action. The present results indicated that (1) fluoxetine (administrated intragastrically, 30 mg/kg; not subactive dose: 15 mg/kg) significantly reduced IFN-alpha-induced increase of the immobility time in the forced swimming test; (2) 5-HT(1A) receptor- and 5-HT(1B) receptor ligands alone or in combination had no effects on IFN-alpha-induced increase of the immobility time in the FST; (3) surprisingly, WAY 100635 (5-HT(1A) receptor antagonist, 634908-75-1) and 8-OH-DPAT(5-HT(1A) receptor agonist, CAS 78950-78-4) markedly enhanced the antidepressant effect of fluoxetine at the subactive dose (15 mg/kg, i. g.) on the IFN-alpha-treated mice in the FST. Further investigations showed that fluoxetine combined with WAY 100635 and 8-OH-DPAT failed to produce antidepressant effects in the FST. (4) Co-application of CGS 12066A (5-HT(1B) receptor agonist, CAS 109028-09-3) or GR 127935 (5-HT(1B/1D) receptor antagonist, CAS 148642-42-6) with fluoxetine had no synergistic effects on the IFN-alpha-induced increase of immobility time in FST. (5) Interestingly, co-administration of GR 127935, WAY 100635 and fluoxetine significantly reduced the IFN-alpha-induced increase in immobility time of FST, being more effective than co-administration of WAY 100635 and fluoxetine. All results suggest that (1) compared to

Status of helium-production reaction studies with a spallation neutron source

International Nuclear Information System (INIS)

Haight, R.C.; Bateman, F.B.; Chadwick, M.B.

1994-01-01

Alpha--particle production cross sections and spectra are being measured at the spallation source of fast neutrons at the Los Alamos Meson Physics Facility (LAMPF). Detectors at angles of 30, 60, 90 and 135 degree are used to identify alpha particles, measure their energy spectra, and indicate the time-of-flight, and hence the energy, of the neutrons inducing the reaction. The useful neutron energy ranges from less than 1 MeV to approximately 50 MeV for the present experimental setup. Targets under study at present include C, N, O, 27 Al, Si, 51 V, 56 Fe, 59 Co, 58,60 Ni, 89 Y and 93 Nb. Results for 59 Co illustrate the capabilities of the approach

Investigation of Activation Cross-Sections of Alpha-Induced Nuclear Reactions on Natural Silver

International Nuclear Information System (INIS)

Shahid, Muhammad; Kim, Kwangsoo; Naik, Haladhara; Zaman, Muhammad; Kang, Sinchul; Huh, Changgi; Kim, Guinyun

2015-01-01

The purpose was to study the production route of some radioisotopes applicable in medicine and industry. The measured results were compared with literature data and theoretical values. The nat Ag(α,x) reaction has already been studied for different energy ranges. However, the literature data needed new data set to increase the reliability of the reported results. The current experimental work will be helpful to make the literature data more reliable and to modify the theoretical models. The literature data needed new data set to increase the reliability of the reported results. The current experimental work is helpful to make the literature data more reliable and to modify the theoretical models

Slowing-down calculation for charged particles, application to the calculation of the (alpha, neutron) reaction yield in UO2 - PuO2 fuel

International Nuclear Information System (INIS)

Dulieu, P.

1967-11-01

There are no complete theory nor experimental data sufficient to predict exactly, in a systemic way, the slowing down power of any medium for any ion with any energy. However, in each case, the energy range can be divided in three areas, the low energiy range where the de/dx is an ascending energy function, the intermediate energy region where de/dx has a maximum, the high energy region where de/dx is a descending energy function. In practice, the code Irma 3 allows to obtain with a good precision de/dx for the protons, neutrons, tritons, alphas in any medium. For particles heavier than alpha it is better to use specific methods. In the case of calculating the yield of the (alpha, neutron) reaction in a UO 2 -PuO 2 fuel cell, the divergences of experimental origin, between the existing data lead to adopt a range a factor 1.7 on the yields [fr

Detonation Synthesis of Alpha-Variant Silicon Carbide

Science.gov (United States)

Langenderfer, Martin; Johnson, Catherine; Fahrenholtz, William; Mochalin, Vadym

2017-06-01

A recent research study has been undertaken to develop facilities for conducting detonation synthesis of nanomaterials. This process involves a familiar technique that has been utilized for the industrial synthesis of nanodiamonds. Developments through this study have allowed for experimentation with the concept of modifying explosive compositions to induce synthesis of new nanomaterials. Initial experimentation has been conducted with the end goal being synthesis of alpha variant silicon carbide (α-SiC) in the nano-scale. The α-SiC that can be produced through detonation synthesis methods is critical to the ceramics industry because of a number of unique properties of the material. Conventional synthesis of α-SiC results in formation of crystals greater than 100 nm in diameter, outside nano-scale. It has been theorized that the high temperature and pressure of an explosive detonation can be used for the formation of α-SiC in the sub 100 nm range. This paper will discuss in detail the process development for detonation nanomaterial synthesis facilities, optimization of explosive charge parameters to maximize nanomaterial yield, and introduction of silicon to the detonation reaction environment to achieve first synthesis of nano-sized alpha variant silicon carbide.

A brief overview of models of nucleon-induced reactions

International Nuclear Information System (INIS)

Carlson, B.V.

2003-01-01

The basic features of low to intermediate energy nucleon-induced reactions are discussed within the contexts of the optical model, the statistical model, preequilibrium and intranuclear cascade models. The calculation of cross sections and other scattering quantities are described. (author)

The serum concentration of tumor necrosis factor alpha is not an index of growth-hormone- or obesity-induced insulin resistance.

Science.gov (United States)

Pincelli, A I; Brunani, A; Scacchi, M; Dubini, A; Borsotti, R; Tibaldi, A; Pasqualinotto, L; Maestri, E; Cavagnini, F

2001-01-01

The tumor necrosis factor alpha (TNF-alpha) might play a central role in insulin resistance, a frequent correlate of obesity likely contributing to some obesity-associated complications. Adult growth hormone (GH) deficiency syndrome (GHDA) shares with obesity excessive fat mass, hyperlipidemia, increased cardiovascular risk, and insulin resistance. On the other hand, GH has been shown to induce transient deterioration of glucose metabolism and insulin resistance when administered in normal humans and in GHDA patients. No information is presently available on the relationship between serum TNF-alpha levels and insulin sensitivity in GHDA. We compared the serum TNF-alpha levels found in 10 GHDA patients before and after a 6-month recombinant human GH therapy (Genotropin), in an insulin resistance prone population of 16 obese (OB) patients and in 38 normal-weight healthy blood donors (controls). The insulin sensitivity was assessed by a euglycemic-hyperinsulinemic glucose clamp in all the GHDA patients and in 10 OB and in 6 control subjects. The serum TNF-alpha levels were not significantly different in OB patients (42.2 +/- 12.81 pg/ml), in GHDA patients at baseline (71.3 +/- 23.97 pg/ml), and in controls (55.3 +/- 14.28 pg/ml). A slight decrease of TNF-alpha values was noted in GHDA patients after 6 months of recombinant human GH treatment (44.5 +/- 20.19 pg/ml; NS vs. baseline). The insulin sensitivity (M) was significantly reduced in OB patients (2.4 +/- 0.30 mg/kg/min) as compared with control subjects (7.5 +/- 0.39 mg/kg/min) and in GHDA patients both at baseline (6.6 +/- 0.6 mg/kg/min) and after recombinant human GH therapy (5.6 +/- 0.7 mg/kg/min). The insulin sensitivity in the GHDA patients, similar to that of controls at baseline, worsened after recombinant human GH treatment (p < 0.05 vs. baseline; p = 0.05 vs. controls). Linear regression analysis showed no correlation between TNF-alpha and M values (see text) in all patient groups. These data indicate

Inhibition of polymerases-alpha and -beta completely blocks DNA repair induced by UV irradiation in cultured mouse neuronal cells

International Nuclear Information System (INIS)

Licastro, F.; Sarafian, T.; Verity, A.M.; Walford, R.L.

1985-01-01

The effects of hydroxyurea, aphidicolin and dideoxythymidine on UV-induced DNA repair of mouse neuronal granular cells were studied. Aphidicolin, which is considered a specific inhibitor of polymerase-alpha, decreased spontaneous DNA synthesis by 93% and totally suppressed DNA repair. Dideoxythymidine, an inhibitor of polymerase-beta, was more potent in decreasing scheduled DNA synthesis than aphidicolin, and also completely blocked the UV-induced DNA repair. Hydroxyurea, a specific inhibitor of ribonucleotide reductase, inhibited scheduled DNA synthesis, but unscheduled DNA synthesis after UV irradiation was always well detectable. Our data suggest that in neuronal cells from 5 to 10 days old mice both polymerases-alpha and -beta are required for both DNA synthesis and repair. These two enzymes may act jointly in filling up the gaps along the DNA molecule and elongating the DNA chain

Molecular mechanisms underlying mancozeb-induced inhibition of TNF-alpha production

International Nuclear Information System (INIS)

Corsini, Emanuela; Viviani, Barbara; Birindelli, Sarah; Gilardi, Federica; Torri, Anna; Codeca, Ilaria; Lucchi, Laura; Bartesaghi, Stefano; Galli, Corrado L.; Marinovich, Marina; Colosio, Claudio

2006-01-01

Mancozeb, a polymeric complex of manganese ethylenebisdithiocarbamate with zinc salt, is widely used in agriculture as fungicide. Literature data indicate that ethylenebisdithiocarbamates (EBDTCs) may have immunomodulatory effects in humans. We have recently found in agricultural workers occupationally exposed to the fungicide mancozeb a statistically significant decrease in lipopolysaccharide (LPS)-induced tumor necrosis factor-alpha (TNF) production in leukocytes. TNF is an essential proinflammatory cytokine whose production is normally stimulated during an infection. The purpose of this work was to establish an in vitro model reflecting in vivo data and to characterize the molecular mechanism of action of mancozeb. The human promyelocytic cell line THP-1 was used as in vitro model to study the effects of mancozeb and its main metabolite ethylenthiourea (ETU) on LPS-induced TNF release. Mancozeb, but not ETU, at non-cytotoxic concentrations (1-100 μg/ml), induced a dose- and time-dependent inhibition of LPS-induced TNF release, reflecting in vivo data. The modulatory effect observed was not limited to mancozeb but also other EBDTCs, namely zineb and ziram, showed similar inhibitory effects. Mancozeb must be added before or simultaneously to LPS in order to observe the effect, indicating that it acts on early events triggered by LPS. It is known that nuclear factor-κB (NF-κB) tightly regulates TNF transcription. We could demonstrate that mancozeb, modulating LPS-induced reactive oxygen species generation, prevented IκB degradation and NF-κB nuclear translocation, which in turn resulted in decreased TNF production. To further understand the mechanism of the effect of mancozeb on TNF transcription, THP-1 cells were transfected with NF-κB promoter-luciferase construct, and the effect of mancozeb on luciferase activity was measured. Cells transfected with promoter constructs containing κB site showed decreased LPS-induced luciferase activity relative to control

Partial deficiency of HIF-1 alpha stimulates pathological cardiac changes in streptozotocin-induced diabetic mice

Czech Academy of Sciences Publication Activity Database

Bohuslavová, Romana; Kolář, František; Sedmera, David; Škvorová, Lada; Papoušek, František; Neckář, Jan; Pavlínková, Gabriela

2014-01-01

Roč. 14, Feb 6 (2014) ISSN 1472-6823 R&D Projects: GA ČR GA301/09/0117; GA MŠk(CZ) ED1.1.00/02.0109 Institutional research plan: CEZ:AV0Z50520701 Institutional support: RVO:68378271 Keywords : Echocardiographic parameters * Hypoxia inducible factor 1 alpha * Diabetic cardiomyopathy Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 1.710, year: 2014

1-4 Strangeness Production in Antiproton Induced Nuclear Reactions.

Institute of Scientific and Technical Information of China (English)

Feng; Zhaoqing[1

2014-01-01

More localized energy deposition is able to be produced in antiproton-nucleus collisions in comparison withheavy-ion collisions due to annihilation reactions. Searching for the cold quark-gluon plasma (QGP) with antiprotonbeamshas been considered as a hot topic both in experiments and in theretical calculations over the past severaldecades. Strangeness production and hypernucleus formation in antiproton-induced nuclear reactions are importancein exploring the hyperon (antihyperon)-nucleon (HN) potential and the antinucleon-nucleon interaction, whichhave been hot topics in the forthcoming experiments at PANDA in Germany.

A semiconductor counter telescope for neutron reaction studies

Energy Technology Data Exchange (ETDEWEB)

Lalovic, B I; Ajdacic, V S [Institute of nuclear sciences Boris Kidric, Vinca, Beograd (Yugoslavia)

1963-12-15

A counter telescope consisting of two or three semiconductor counters for {delta}E/{delta}x vs. E analysis was made for studying nuclear reactions induced by 14.4 MeV neutrons. Various factors important for the telescope performance are discussed in details and some solutions for getting an optimum resolution and a low background are given. Protons, deuterons and alpha particles resulting from scattering and reactions of 14.4 MeV neutrons on deuterium, tritium, praseodymium and niobium were detected, and pulses from the counters recorded on a two-dimensional analyzer. These experiments have shown that the telescope compares favorably with other types of telescopes with regards to the upper limit of neutron flux which can be used, (DELTADELTA)x and E resolution, versatility and compactness (author)

Interferons and interferon (IFN)-inducible protein 10 during highly active anti-retroviral therapy (HAART)-possible immunosuppressive role of IFN-alpha in HIV infection

DEFF Research Database (Denmark)

Stylianou, E; Aukrust, P; Bendtzen, K

2000-01-01

-infected patients had raised levels of both IP-10 and IFN-alpha compared with healthy controls (n = 19), with particularly high levels in advanced disease. HAART induced a marked decrease in levels of both IFN-alpha, neopterin and IP-10, though not to normal concentrations. In contrast, IFN-gamma levels were low...

Cross sections measurement of isomeric states formation in nuclear reactions induced by neutrons of 14 Mev and comparison with statistical theories

International Nuclear Information System (INIS)

El Bardouni, T.

1989-01-01

Excitation functions of some (n,2n), (n,p) and (n,alpha) reactions on isotopes taken in different mass regions have been measured around 14 Mev. We give more interest to reactions leading to residual nucleus in isomeric states. Quasi-monoenergetic neutrons are produced via the T(d,n)alpha reaction and activation technique is combined to high resolution gamma-ray spectrometry. In the measurement of samples activities, we have scanned carefully the different origins of uncertainties and taken into account all necessary corrections. We have also carried out a detailed study about the nuclear reactions theory (compound nucleus and Geometry Dependent Hybrid Models) in order to compare our measurements results and theoretical calculations. The EMPIRE code (based on compound nucleus and Geometry Dependent Hybrid Models), that we have adapted on IBM Personal Computer, allows us to reproduce with great satisfaction the measured excitation functions without adjusting the models parameters. So we can rely on the EMPIRE code, as it is done in its work, in the prediction of some nuclear reactions excitation functions that cannot be determined by means of activation technique and gamma-ray spectrometry. 88 refs., 43 figs., 16 tabs., 1 chart. (author)

Probability of bystander effect induced by alpha-particles emitted by radon progeny using the analytical model of tracheobronchial tree

International Nuclear Information System (INIS)

Jovanovic, B.; Nikezic, D.

2010-01-01

Radiation-induced biological bystander effects have become a phenomenon associated with the interaction of radiation with cells. There is a need to include the influence of biological effects in the dosimetry of the human lung. With this aim, the purpose of this work is to calculate the probability of bystander effect induced by alpha-particle radiation on sensitive cells of the human lung. Probability was calculated by applying the analytical model cylinder bifurcation, which was created to simulate the geometry of the human lung with the geometric distribution of cell nuclei in the airway wall of the tracheobronchial tree. This analytical model of the human tracheobronchial tree represents the extension of the ICRP 66 model, and follows it as much as possible. Reported probabilities are calculated for various targets and alpha-particle energies. Probability of bystander effect has been calculated for alpha particles with 6 and 7.69 MeV energies, which are emitted in the 222 Rn chain. The application of these results may enhance current dose risk estimation approaches in the sense of the inclusion of the influence of the biological effects. (authors)

Low-energy deuteron-induced reactions on Nb-93

Czech Academy of Sciences Publication Activity Database

Avrigeanu, M.; Avrigeanu, V.; Bém, Pavel; Fischer, U.; Honusek, Milan; Koning, A.J.; Mrázek, Jaromír; Šimečková, Eva; Štefánik, Milan; Závorka, Lukáš

2013-01-01

Roč. 88, č. 1 (2013), 014612 ISSN 0556-2813 R&D Projects: GA MŠk(XE) LM2011019 Institutional support: RVO:61389005 Keywords : deuteron-induced reactions * cross sections * breakup mechanism Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 3.881, year: 2013 http://prc.aps.org/pdf/PRC/v88/i1/e014612

Table of nuclear reactions and subsequent radioactive dacays induced by 14-MeV neutrons

International Nuclear Information System (INIS)

Tsukada, Kineo

1977-09-01

Compilation of the data on nuclear reactions and subsequent radioactive decays induced by 14-MeV neutrons is presented in tabular form for most of the isotopes available in nature and for some of the artificially-produced isotopes, including the following items: Nuclide (isotopic abundance), type of nuclear reaction, reaction Q-value, reaction product, type of decay, decay Q-value, half-life of reaction product, decay product, maximum reaction cross section, neutron energy for maximum cross section, reaction cross section for 14 MeV neutrons, saturated radioactivity induced by irradiation of a neutron flux of 1 n/cm 2 sec for a mol of atoms, and reference for the cross section. The mass number dependence of (n, γ), (n, 2n), (n, p), (n, d), (n, t), (n, 3 He) and (n, α) reaction cross sections for 14-MeV neutrons is given in figures to show general trends of the cross sections

A compilation of information on the {sup 31}P(p,{alpha}){sup 28}Si reaction and properties of excited levels in the compound nucleus {sup 32}S

Energy Technology Data Exchange (ETDEWEB)

Miller, R.E.; Smith, D.L. [Argonne National Lab., IL (United States). Technology Development Div.

1997-11-01

This report documents a survey of the literature, and provides a compilation of data contained therein, for the {sup 31}P(p,{alpha}){sup 28}Si reaction. Attention is paid here to resonance states in the compound-nuclear system {sup 32}S formed by {sup 31}P + p, with emphasis on the alpha-particle decay channels, {sup 28}Si + {alpha} which populate specific levels in {sup 28}Si. The energy region near the proton separation energy for {sup 32}S is especially important in this context for applications in nuclear astrophysics. Properties of the excited states in {sup 28}Si are also considered. Summaries of all the located references are provided and numerical data contained in them are compiled in EXFOR format where applicable.

Cross-section calculations for neutron-induced reactions up to 50 MeV

International Nuclear Information System (INIS)

Yamamuro, Nobuhiro.

1996-01-01

In the field of accelerator development, medium-energy reaction cross-section data for structural materials of accelerator and shielding components are required, especially for radiation protection purposes. For a d + Li stripping reaction neutron source used in materials research, neutron reaction cross sections up to 50 MeV are necessary for the design study of neutron irradiation facilities. The current version of SINCROS-II is able to calculate neutron and proton-induced reaction cross sections up to ∼ 50 MeV with some modifications and extensions of the cross-section calculation code. The production of isotopes when structural materials and other materials are bombarded with neutrons or protons is calculated using a revised code in the SINCROS-II system. The parameters used in the cross-section calculations are mainly examined with proton-induced reactions because the experimental data for neutrons above 20 MeV are rare. The status of medium mass nuclide evaluations for aluminum, silicon, chromium, manganese, and copper is presented. These data are useful to estimate the radiation and transmutation of nuclei in the materials

Production and decay of baryonic resonances in pion induced reactions

Directory of Open Access Journals (Sweden)

Przygoda Witold

2016-01-01

Full Text Available Pion induced reactions give unique opportunities for an unambiguous description of baryonic resonances and their coupling channels. A systematic energy scan and high precision data, in conjunction with a partial wave analysis, allow for the study of the excitation function of the various contributions. A review of available world data unravels strong need for modern facilities delivering measurements with a pion beam. Recently, HADES collaboration collected data in pion-induced reactions on light (12C and heavy (74W nuclei at a beam momentum of 1.7 GeV/c dedicated to strangeness production. It was followed by a systematic scan at four different pion beam momenta (0.656, 0.69, 0.748 and 0.8 GeV/c in π− − p reaction in order to tackle the role of N(1520 resonance in conjunction with the intermediate ρ production. First results on exclusive channels with one pion (π− p and two pions (nπ+π−, pπ−π0 in the final state are discussed.

Human FcγRIIA induces anaphylactic and allergic reactions.

Science.gov (United States)

Jönsson, Friederike; Mancardi, David A; Zhao, Wei; Kita, Yoshihiro; Iannascoli, Bruno; Khun, Huot; van Rooijen, Nico; Shimizu, Takao; Schwartz, Lawrence B; Daëron, Marc; Bruhns, Pierre

2012-03-15

IgE and IgE receptors (FcεRI) are well-known inducers of allergy. We recently found in mice that active systemic anaphylaxis depends on IgG and IgG receptors (FcγRIIIA and FcγRIV) expressed by neutrophils, rather than on IgE and FcεRI expressed by mast cells and basophils. In humans, neutrophils, mast cells, basophils, and eosinophils do not express FcγRIIIA or FcγRIV, but FcγRIIA. We therefore investigated the possible role of FcγRIIA in allergy by generating novel FcγRIIA-transgenic mice, in which various models of allergic reactions induced by IgG could be studied. In mice, FcγRIIA was sufficient to trigger active and passive anaphylaxis, and airway inflammation in vivo. Blocking FcγRIIA in vivo abolished these reactions. We identified mast cells to be responsible for FcγRIIA-dependent passive cutaneous anaphylaxis, and monocytes/macrophages and neutrophils to be responsible for FcγRIIA-dependent passive systemic anaphylaxis. Supporting these findings, human mast cells, monocytes and neutrophils produced anaphylactogenic mediators after FcγRIIA engagement. IgG and FcγRIIA may therefore contribute to allergic and anaphylactic reactions in humans.

Electrospray ionization mass spectrometric investigations of [alpha]-dicarbonyl compounds--Probing intermediates formed in the course of the nonenzymatic browning reaction of l-ascorbic acid

Science.gov (United States)

Schulz, Anke; Trage, Claudia; Schwarz, Helmut; Kroh, Lothar W.

2007-05-01

A new method is presented which allows the simultaneous detection of various [alpha]-dicarbonyl compounds generated in the course of the nonenzymatic browning reaction initiated by thermal treatment of l-ascorbic acid, namely: glyoxal, methylglyoxal, diacetyl, 3-deoxy-l-pentosone, and l-threosoneE 3-Deoxy-l-threosone was successfully identified as a new C4-[alpha]-dicarbonyl structure for the first time in the degradation of Vitamin C by application of this non-chromatographic mass spectrometric approach. Moreover, a more detailed elucidation of the mechanistic scenario with respect to the oxidative and nonoxidative pathways is presented by using dehydro-l-ascorbic acid and 2,3-diketo-l-gulonic acid instead of l-ascorbic acid as a starting material. Furthermore, the postulated pathways are corroborated with the aid of 13C-isotopic labeling studies. The investigations were extended to baby food, and the successful detection of [alpha]-dicarbonyl compounds characteristic for Vitamin C degradation proved the matrix tolerance of the introduced method.

Effects of andrographolide on intrahepatic cholestasis induced by alpha-naphthylisothiocyanate in rats.

Science.gov (United States)

Khamphaya, Tanaporn; Chansela, Piyachat; Piyachaturawat, Pawinee; Suksamrarn, Apichart; Nathanson, Michael H; Weerachayaphorn, Jittima

2016-10-15

Cholestasis is a cardinal manifestation of liver diseases but effective therapeutic approaches are limited. Therefore, alternative therapy for treating and preventing cholestatic liver diseases is necessary. Andrographolide, a promising anticancer drug derived from the medicinal plant Andrographis paniculata, has diverse pharmacological properties and multi-spectrum therapeutic applications. However, it is unknown whether andrographolide has a hepatoprotective effect on intrahepatic cholestasis. The aims of this study were to investigate the protective effect and possible mechanisms of andrographolide in a rat model of acute intrahepatic cholestasis induced by alpha-naphthylisothiocyanate (ANIT). Andrographolide was administered intragastrically for four consecutive days, with a single intraperitoneal injection of ANIT on the second day. Liver injury was evaluated biochemically and histologically together with hepatic gene and protein expression analysis. Rats pretreated with andrographolide prior to ANIT injection demonstrated lower levels of serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma-glutamyltransferase, as well as bilirubin and bile acids as compared to rats treated with ANIT alone. Andrographolide also decreased the incidence and extent of periductular fibrosis and bile duct proliferation. Analysis of protein expression in livers from andrographolide-treated cholestatic rats revealed markedly decreased expression of alpha-smooth muscle actin and nuclear factor kappa-B (NF-κB). In conclusion, andrographolide has a potent protective property against ANIT-induced cholestatic liver injury. The mechanisms that underlie this protective effect are mediated through down-regulation of NF-κB expression and inhibition of hepatic stellate cell activation. These findings suggest that andrographolide could be a promising therapeutic option in prevention and slowing down the progression of cholestatic liver diseases. Copyright �

Effects of x-ray irradiation on the induction of. cap alpha. -amylase synthesis by gibberelic acid in the aleurone system of barley