Introduction and objective. In the light of current data concerning the growing exposure to ionizing radiation (IR) originating from atrificial sources, especially from medical ones, and also related to occupational exposure, it is justifiable to systematize the state of knowledge concerning the effect of IR on the male reproductive system. Brief description of the state of knowledge. There is no basis for the application of the hypothesis of hormesis in the area of male reproductive health. Regarding the impact of IR on spermatogenesis, spermatogonia are less susceptible to the occurrence of DNA damage after exposition to IR, but are characterized by slower DNA repair compared to somatic cells. Damage to the genes after exposure to IR is possible at each stage of spermatogenesis; however, haploidal spermatids show the highest radiosensitivity in this respect. The genetic risk of the cells differentiating during spermatogenesis is limited to one cycle of spermatogenesis, whereas the genetic instability may persist for the whole period of life, and DNA damage induced by IR may be transmitted to future generations. The minimum dose causing detectable DNA damage was 30 Gy. While exceeding this dose, the number of single-strand DNA breaks increases. Among males exposed to IR, a decrease was observed in sperm motility and in the percentage of morphologically normal spermatozoa as well as in an intensification of vacuolization. The genetic material in the sperm of these males showed higher fragmentation and methylation of genomic DNA. Conclusion. In the context of the epidemiological situation concerning the prevalence of infertility, while assessing the health effects of exposure to IR from artificial, including medical sources, the reproductive risk should be considered.
Introduction and objective. The tendency towards postponement of maternity implies a greater exposure of female germ cells to damaging environmental effects, including ionizing radiation (IR). Progress in paediatric oncology, based on the use of radiotherapy, also implies the occurrence of gonadal dysfunctions and subsequent female fertility disorders. Therefore, it seems justifiable to systematize the state of knowledge concerning the effect of IR on the female reproductive system. Brief description of the state of knowledge. A considerable part of studies concerning the effect of IR on female germ cells have been conducted on animals. Their extrapolation to humans is hindered because in animal studies high acute exposures are applied, which do not reflect human environmental exposures characterized by chronic low dose exposure. Studies on animals provide a heterogenous image, which hinders the formulation of unequivocal conclusions and indicates that radiosensitivity depends, i.a. on IR dose, stage of development of oocytes, the applied marker of the effects of IR, or on the species. LD50 of human oocytes is estimated to be below 2 Gy. The effect of IR depends, i.a. on the dose fractionation and the age (older women are more radiosensitive). In females, the effective sterilizing dose is: at birth 20.3 Gy, at 10 years 18.4 Gy, at 20 years 16.5 Gy, whereas at 30 years 14.3 Gy, which is associated with the available pool of ovarian follicles. Conclusions. Within the range of low doses received as a result of environmental exposure to IR, there is no evidence for the occurrence of either adverse pregnancy outcomes, nor fertility disorders in females. These effects may be related to the cancer radiotherapy, or exposure to high IR doses during nuclear accidents.
The aim of this study was to analyse the content of reducing sugars in beverages obtained on the basis of apple juice with the addition of fructans. Moreover, the effect of consumption of this prebiotic beverage on the constipation was analysed.
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