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Studies on the biological effects of ozone:
11. Release of factors from human endothelial cells.
Valacchi G, Bocci V.
Institute of General Physiology, University of Siena, Italy.
BACKGROUND: Empirical observations have shown that ozonated
autohemotherapy markedly improves the symptoms of chronic limb
ischemia (muscular pain at rest, intermittent claudication, etc)
in atherosclerotic patients, but mechanisms of action remain
unclear. AIMS: Human endothelial cells (HUVECs) are known to
release nitrogen monoxide (NO) and we investigated the
biological effects of human ozonated serum on HUVECs in culture.
METHODS: We assessed the relevance of peroxidation, the release
of NO as nitrite and of three classical cytokines. RESULTS: The
treatment of HUVECs with ozonated serum yields a dose dependent
increase of thiobarbituric acid reactive substances (TBARS) and
of hydrogen peroxide (H2O2) and a decrease of protein thiol
groups (PTG). Concomitantly, in comparison to either the control
or the oxygenated sample, there is a significant and steady
increase of nitric oxide (NO) production; this is markedly
enhanced by the addition of L-arginine (20 microM) and inhibited
in the presence of the NO inhibitor, L-NAME (20 mM). The main
mediator of ozone action is H2O2 as it has been shown either
after its direct measurement or by the addition of 20, 40 and
100 microM. Moreover, during 24 hours incubation we have
investigated the production of endothelin 1 (ET-1), E-selectin
and Interleukin 8 (IL-8) and it appears that ozonation enhances
IL-8, inhibits E-selectin and hardly modifies ET-1 production.
CONCLUSIONS: It appears that reinfusion of ozonated blood, by
enhancing release of NO, may induce vasodilation in ischemic
areas and reduce hypoxia.
PMID: 11213910 [PubMed - indexed for MEDLINE]
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Evaluation of electrochemically
generated ozone for the disinfection of water and
wastewater.
Tanner BD, Kuwahara S, Gerba CP, Reynolds KA.
Dept of Microbiology and Immunology, University of
Arizona, Tucson, AZ 85721, USA. btanner@u.arizona.edu
Effective wastewater treatment is critical to public
health and well-being. This is especially true in
developing countries, where disinfection of wastewater
is frequently inadequate. People who live in these areas
may benefit from wastewater disinfection using ozone.
This study evaluated the ability of a new
electrochemical process of ozone generation, which
produced ozone continuously at high pressure and
concentration by the electrolysis of water, to disinfect
tap water and secondarily treated wastewater.
Inactivation of Klebsiella terrigena, Escherichia coli,
MS2 bacteriophage and poliovirus 1 was evaluated first
in reverse osmosis (RO) treated water. Inactivation of
K. terrigena (6-log), E. coli (6-log), MS2 (6-log) and
poliovirus 1 (>3-log) was observed after 1 min of
ozonation in a 1 L batch reactor. Experiments were then
performed to assess the microbiological impact of
disinfection using ozone on secondarily treated
municipal wastewater. The effect of ozonation on
wastewater was determined for total and faecal coliforms,
bacteriophages and heterotrophic plate count (HPC)
bacteria. Electrochemical ozone generators provided an
effective, rapid and low-cost method of wastewater
disinfection. Based on the results of this research,
electrochemically generated ozone would be well suited
to remote, small-scale, disinfection operations and may
provide a feasible means of wastewater disinfection in
developing countries.
PMID: 15318481 [PubMed - in process]
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