Live-cell imaging study of mitochondrial morphology in mammalian cells exposed to X-rays

A study on legal and medical dimensions of radiation exposure in neurosurgery clinics in Turkish practice

Background:

In the present study, the first aim was to address the detrimental effects of the fluoroscopy procedure performed by physicians and other health-care professionals in neurosurgery clinics, then to examine precautions that should be taken to avoid harmful effects of radiation and radioactive substances during this process. The second aim was to handle the rights provided for health-care professionals exposed to the radiation in workplaces.

Methods:

A standardized questionnaire was used for a multicenter survey. Volunteer, intellectual, and cooperative participants (n = 41) were randomly chosen. The survey was prepared considering reports drawn up by the International Atomic Energy Agency. The questions concerning safe and effective fluoroscopy procedure were asked to the participants. The answers received were statistically evaluated. The alpha significance value was accepted as 0.05.

Results:

Two neurosurgeons only knew the legal rights that they might possess due to the exposure to the radiation or radioactive substances.

Conclusion:

The survey conducted among the health-care professionals revealed the insufficiency of knowledge about the protection from the radiation exposure or radioactive substances in workplaces. Furthermore, both health-care professionals working in radiology clinics, and those in neurosurgery and other clinics who are likely to be exposed to the radiation or radioactive substances have the rights afforded by the law.

Targeted Nuclear Irradiation with an X-Ray Microbeam Enhances Total JC-1 Fluorescence from Mitochondria

Several studies have demonstrated that mitochondria are critically involved in the pleiotropic manifestation of radiation effects. While conventional whole-cell irradiation compromises the function of mitochondria, the effects of subcellular targeted radiation are not yet fully understood. In this study, normal human diploid cells with cell-cycle indicators were irradiated using a synchrotron X-ray microbeam, and mitochondrial membrane potential was quantified by JC-1 over the 72-h period postirradiation. Cytoplasmic irradiation was observed to temporarily enlarge the mitochondrial area with high membrane potential, while the total mitochondrial area did not change significantly. Unexpectedly, cell-nucleus irradiation promoted a similar increase not only in the mitochondrial areas with high membrane potential, but also in those with low membrane potential, which gave rise to the apparent increase in the total mitochondrial area. Augmentation of the mitochondrial area with low membrane potential was predominantly observed among G1 cells, suggesting that nucleus irradiation during the G1 phase regulated the mitochondrial dynamics of the cytoplasm, presumably through DNA damage in the nucleus.