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Description:
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This study examines the carcinogenic effect of HZE radiation and protective
effects of different types of diets against colon carcinogenesis in a rat model .
The effect of HZE radiation on health state and colon cancer development was
evaluated . HZE radiation was found to suppress food consumption (P <0 .0001 ) leading to
lower body weight gain of irradiated rats when compared to the non -irradiated rats
(P <0 .05 ) . The animals exposed to HZE radiation were found to start dying and /or getting
pathologies 11 weeks earlier and at the end of the study had morbidity /mortality rate
14 .2 % higher (P=0 .0005 ) than non -irradiated rats . There was no significant effect of
HZE radiation on colon cancer incidence .
The effects of dietary fibers and oils on health state and colon carcinogenesis
were evaluated . Morbidity /mortality was found to be delayed in rats fed with pectinbased
diets when compared to cellulose -based diet , regardless of radiation treatment .
Similarly , fish oil was found to beneficially affect health of the experimental animals
when compared to corn oil . Ten - and twenty -week delayed morbidity /mortality for
irradiated and non -irradiated groups , respectively , was observed for rats fed with fish
oil -based diets when compared to corn oil -based diets . Fish oil was also found to
significantly reduce colon tumor incidence and multiplicity in non -irradiated rats
(P <0 .05 ) . A similar trend was observed for the irradiated animals . No significant effect
of fiber on colon cancer incidence was found .
Finally , the effect of diets on general health and colon cancer development was
investigated . Rats fed with corn oil /cellulose diet started dying and /or getting a disease
earlier than rats fed with other diets , regardless of radiation treatment . The effect of diet
on colon cancer development was found to depend on radiation treatment . Thus , in the
absence of radiation treatment fish oil /cellulose was found to significantly reduce tumor
incidence and multiplicity when compared to corn oil /pectin diet (P <0 .05 ) . In the
presence of radiation treatment fish oil /pectin was found to lower the values of tumor
incidence and tumor multiplicity , though the data obtained were not significant . |