Electric foot-shock stress drives TNF-alpha production in the liver of IL-6-deficient mice

Objectives: Accumulating evidence has shown that interleukin-6 (IL-6) has pleiotropic effects on a variety of biological functions, including its antiapoptotic potential during liver injury. Our previous work demonstrated that restraint stress-induced elevation of plasma IL-6 negatively regulates plasma tumor necrosis factor-alpha (TNF-alpha). Herein, we further clarified the mechanism underlying the above finding and investigated the effect of IL-6 on liver apoptosis triggered by stress. Methods: Male C57BL/6J and IL-6-deficient C57BL/SV129 mice were exposed to 1 h of electric foot-shock stress. Thereafter, the serum, liver and spleen TNF-alpha levels were measured at several time points. Serum alanine aminotransferase (ALT), liver caspase-3 and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling ( TUNEL) activities were analyzed to evaluate the severity of liver injury and apoptosis. Results: The liver, but not the spleen, of the IL-6-deficient mice exhibited a significant increase in TNF-alpha level after stress in parallel with serum TNF-alpha elevation, whereas no such TNF-alpha responses were found in the wild animals. No significant differences in stress-induced elevation of serum ALT levels, liver caspase-3 activities and the number of TUNEL-positive hepatocytes were found between the wild and IL-6-deficient mice. Conclusions: Taken together, these results indicate that IL-6 may play a critical role in suppressing TNF-alpha production in the liver, thereby decreasing the blood TNF-alpha level. In contrast, IL-6 secretion was shown to have no protective effect on stress-triggered liver injury. Copyright (C) 2004 S. Karger AG, Basel

Effects of cAMP on the composition of berry juice in Muscat Bailey A

In Muscat Bailey A, the increases of organic acids due to cAMP prebloom application 3 weeks before final harvest were accompanied by increases of glucose and fructose, though these increments compared with control diminished toward full maturity. Der Einfluß von cyclischem Adenosin-3' ,5' -monophosphat auf die Zusammensetzung des Beerensaftes bei Muscat Bailey A Wurden die Infloreszenzen der Rebsorte Muscat Bailey A (Vitis labrusca L. x V. vinifera L.) vor der Blüte mit cAMP behandelt, so war 3 Wochen vor der vollen Reife ein Anstieg des Säuregehaltes und ebenso der Glucose- und Fructosekonzentration zu verzeichnen; gegen Ende der Reifephase waren die Unterschiede im Glucose- und Fructosegehalt behandelter und unbehandelter Beeren allerdings ziemlich verwischt

Increase of the acid contents in grape berries by treatment with cAMP

cAMP prebloom application to flower clusters of the grapevine variety Delaware (Vitis labruscana BAILEY) raised the content of organic acids in the repening berries. The total content of amino acids in the juice was raised by postbloom application, alanine, arginine and γ-aminobutyric acid being increased, whereas tyrosine was decreased. Zunahme des Säuregehaltes reifender Traubenbeeren durch Behandlung mit cyclischemAdenosin-3',5' -monophosphat Bei der Rebsorte Delaware wurde durch Behandlung der Infloreszenzen mit cAMP vor der Blüte der Gehalt des Beerensaftes an organischen Säuren erhöht.Durch cAMP-Behandlung nach der Blüte wurde der Gesamtgehalt der Aminosäuren gesteigert, wobei Alanin, Arginin und γ-Aminobuttersäure zunahmen, während die Tyrosinkonzentration verringert war. &nbsp

Photoelectron Angular Distributions for Two-photon Ionization of Helium by Ultrashort Extreme Ultraviolet Free Electron Laser Pulses

Phase-shift differences and amplitude ratios of the outgoing $s$ and $d$ continuum wave packets generated by two-photon ionization of helium atoms are determined from the photoelectron angular distributions obtained using velocity map imaging. Helium atoms are ionized with ultrashort extreme-ultraviolet free-electron laser pulses with a photon energy of 20.3, 21.3, 23.0, and 24.3 eV, produced by the SPring-8 Compact SASE Source test accelerator. The measured values of the phase-shift differences are distinct from scattering phase-shift differences when the photon energy is tuned to an excited level or Rydberg manifold. The difference stems from the competition between resonant and non-resonant paths in two-photon ionization by ultrashort pulses. Since the competition can be controlled in principle by the pulse shape, the present results illustrate a new way to tailor the continuum wave packet.Comment: 5 pages, 1 table, 3 figure

Charge transfer to ground-state ions produces free electrons

Inner-shell ionization of an isolated atom typically leads to Auger decay. In an environment, for example, a liquid or a van der Waals bonded system, this process will be modified, and becomes part of a complex cascade of relaxation steps. Understanding these steps is important, as they determine the production of slow electrons and singly charged radicals, the most abundant products in radiation chemistry. In this communication, we present experimental evidence for a so-far unobserved, but potentially very important step in such relaxation cascades: Multiply charged ionic states after Auger decay may partially be neutralized by electron transfer, simultaneously evoking the creation of a low-energy free electron (electron transfer-mediated decay). This process is effective even after Auger decay into the dicationic ground state. In our experiment, we observe the decay of Ne2+ produced after Ne 1s photoionization in Ne-Kr mixed clusters

Ultrafast Dynamics of a Nucleobase Analogue Illuminated by a Short Intense X-ray Free Electron Laser Pulse

Citation: Nagaya, K., Motomura, K., Kukk, E., Fukuzawa, H., Wada, S., Tachibana, T., . . . Ueda, K. (2016). Ultrafast Dynamics of a Nucleobase Analogue Illuminated by a Short Intense X-ray Free Electron Laser Pulse. Physical Review X, 6(2), 9. doi:10.1103/PhysRevX.6.021035Understanding x-ray radiation damage is a crucial issue for both medical applications of x rays and x-ray free-electron-laser (XFEL) science aimed at molecular imaging. Decrypting the charge and fragmentation dynamics of nucleobases, the smallest units of a macro-biomolecule, contributes to a bottom-up understanding of the damage via cascades of phenomena following x-ray exposure. We investigate experimentally and by numerical simulations the ultrafast radiation damage induced on a nucleobase analogue (5-iodouracil) by an ultrashort (10 fs) high-intensity radiation pulse generated by XFEL at SPring-8 Angstrom Compact free electron Laser (SACLA). The present study elucidates a plausible underlying radiosensitizing mechanism of 5-iodouracil. This mechanism is independent of the exact composition of 5-iodouracil and thus relevant to other such radiosensitizers. Furthermore, we found that despite a rapid increase of the net molecular charge in the presence of iodine, and of the ultrafast release of hydrogen, the other atoms are almost frozen within the 10-fs duration of the exposure. This validates single-shot molecular imaging as a consistent approach, provided the radiation pulse used is brief enough