Radiosensitivity and Hydroxyl Radical Reactivity of Phosphate Esters as Measured by Radiation-induced Dephosphorylation

Oxygen radicals are defined as those molecules that contain an oxygen atom with an unpaired, nonbonding electron (e.g., HO·). Although triplet dioxygen (·O2·) and superoxide ion (O2 - ·) come under this definition, their nonradical chemistry dominates their reactivity, which is discussed in Chapters 6 (·O2·) and 7 (O2-·). The hydroxyl radical (HO·) is the most reactive member of the family of oxygen radicals [HO·, RO·, ·O·, HOO·, ROO·, and RC(O)O·], and is the focus of most oxygen radical research. In the gas phase the dramatic example of oxygen radical reactivity with hydrocarbon substrates is combustion, which is initiated by HO· (or RO· or MO·) and propagated by ·O2· and ·O·.

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Arbutin, an intracellular hydroxyl radical scavenger, protects radiation-induced apoptosis in human lymphoma U937 cells

APOPTOSIS ◽

10.1007/s10495-014-1032-x ◽

2014 ◽

Vol 19 (11) ◽

pp. 1654-1663 ◽

Cited By ~ 16

Author(s):

Li-Hua Wu ◽

Peng Li ◽

Qing-Li Zhao ◽

Jin-Lan Piao ◽

Yu-Fei Jiao ◽

...

Keyword(s):

Hydroxyl Radical ◽

Radical Scavenger ◽

U937 Cells ◽

Hydroxyl Radical Scavenger ◽

Human Lymphoma ◽

Radiation Induced ◽

Induced Apoptosis

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Measurements of total hydroxyl radical reactivity during CABINEX 2009 – Part 1: field measurements

Atmospheric Chemistry and Physics ◽

10.5194/acp-14-2923-2014 ◽

2014 ◽

Vol 14 (6) ◽

pp. 2923-2937 ◽

Cited By ~ 41

Author(s):

R. F. Hansen ◽

S. M. Griffith ◽

S. Dusanter ◽

P. S. Rickly ◽

P. S. Stevens ◽

...

Keyword(s):

Hydroxyl Radical ◽

Flow Reactor ◽

Trace Gases ◽

Field Measurements ◽

Oxidation Products ◽

Radical Reactivity ◽

Inorganic Species ◽

Volatile Organic ◽

Interaction Experiment ◽

Northern Michigan

Abstract. Total hydroxyl radical (OH) reactivity was measured at the PROPHET (Program for Research on Oxidants: PHotochemistry, Emissions, and Transport) forested field site in northern Michigan during the 2009 Community Atmosphere–Biosphere INteraction EXperiment (CABINEX). OH reactivity measurements were made with a turbulent-flow reactor instrument at three heights from the forest floor above (21 and 31 m) and below (6 m) the canopy at three different time periods during the CABINEX campaign. In addition to total OH reactivity measurements, collocated measurements of volatile organic compounds (VOCs), inorganic species, and ambient temperature were made at the different heights. These ancillary measurements were used to calculate the total OH reactivity, which was then compared to the measured values. Discrepancies between the measured and calculated OH reactivity, on the order of 1–24 s−1, were observed during the daytime above the canopy at the 21 and 31 m heights, as previously reported for this site. The measured OH reactivity below the canopy during the daytime was generally lower than that observed above the canopy. Closer analysis of the measurements of OH reactivity and trace gases suggests that the missing OH reactivity could come from oxidation products of VOCs. These results suggest that additional unmeasured trace gases, likely oxidation products, are needed to fully account for the OH reactivity measured during CABINEX.

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Radiation-Induced Cell Lethality of Salmonella typhimurium ATCC 14028: Cooperative Effect of Hydroxyl Radical and Oxygen

Radiation Research ◽

10.2307/3579233 ◽

1995 ◽

Vol 144 (1) ◽

pp. 36 ◽

Cited By ~ 13

Author(s):

Augustine Yonghwi Kim ◽

Donald Wayne Thayer

Keyword(s):

Hydroxyl Radical ◽

Salmonella Typhimurium ◽

Cooperative Effect ◽

Radiation Induced ◽

Cell Lethality

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