Hisanori Fukunaga

Current concerns over the possible effects of low-dose radiation exposure on spermatogenesis requires further elucidation that may be resolved comparing and integrating observed experimental and epidemiological data.

The great earthquake of March 11, 2011, the first of its magnitude to hit Japan in a thousand years, and the consequent tsunami led to unprecedented damage to various areas of the Pacific coast in northeast Japan. Added to these double disasters, residents in Fukushima Prefecture are tormented by the fear of nuclear meltdown at the Fukushima Daiichi nuclear power plant even now. Soma City, with a population of approximately 38,000 people, and Shinchi town, with approximately 8,000 residents, wer

Mitochondrial dysfunction is known to contribute to mitochondrial diseases, as well as to a variety of aging-based pathologies. Mitochondria have their own genomes (mitochondrial DNA (mtDNA)) and the abnormalities, such as point mutations, deletions, and copy number variations, are involved in mitochondrial dysfunction. In recent years, several epidemiological studies and animal experiments have supported the Developmental Origin of Health and Disease (DOHaD) theory, which states that the enviro

Microbeam radiotherapy (MRT) is based on a spatial fractionation of synchrotron X-ray microbeams at the microscale level. Although the tissue-sparing effect (TSE) in response to non-uniform radiation fields was recognized more than one century ago, the TSE of MRT in the testes and its clinical importance for preventing male fertility remain to be determined. In this study, using the combination of MRT techniques and a unique ex vivo testes organ culture, we show, for the first time, the MRT-medi

The genotoxicity of radiation on germ cells may be passed on to the next generation, thus its elucidation is not only a scientific issue but also an ethical, legal, and social issue in modern society. In this article, we briefly overview the effects of radiation on spermatogenesis and its associated genotoxicity, including the latest findings in the field of radiobiology. The potential role of transgenerational effects is still poorly understood, and further research in this area is desirable. F

The formation of sperm by the testes through the process of spermatogenesis is highly radiosensitive and can be affected by environmental, occupational and therapeutic radiation exposures. In this study, we applied an ex vivo mouse testis organ culture as an experimental model of spermatogenesis to investigate the radiobiological effects and to demonstrate its feasibility as a tool to determine response to complex, modulated radiation fields. This model uses Acr-GFP transgenic mice, which expres

The detection of spatiotemporal dose distribution could be of scientific importance for more accurate individual risk assessment of exposure to environmental radiation. Further radiobiological studies on non-uniform radiation-induced biological responses at the tissue level are expected.

We set out to assess the relative age effect (RAE)on UK Nobel laureates in physics, chemistry andphysiology or medicine. The academic year ofthe UK begins in September; therefore, childrenin one classroom may have an entire year’s dif-ference in age (i.e. children born in Septemberand those born in August of different years).This relative age difference could cause a disad-vantage in the younger students compared tothe older students within one classroom.

Precision medicine is a rapidly developing area that aims to deliver targeted therapies based on individual patient characteristics. However, current radiation treatment is not yet personalized; consequently, there is a critical need for specific patient characteristics of both tumor and normal tissues to be fully incorporated into dose prescription. Furthermore, current risk assessment following environmental, occupational, or accidental exposures to radiation is based on population effects, an

Dear Editor, Although it has been gradually recognized that a range of low-dose (or low-dose-rate) radiation effects on living cells are possible key factors in evaluating ‘low-dose radiation risk’, there remains little of the coherence required among robust data that can be used with confidence in risk assessments [1]. It is true that carcinogen risk should be evaluated carefully by considering both clear dose–response relationships and accurate exposure measurements [2]. It may take some ti

This data-driven study offers the most comprehensive view to date on the genetic and physiological significance of mtDNA copy number in cord blood or peripheral blood taken from three generations, totaling more than 1000 individuals. Our findings indicate that mtDNA copy number would be one of the transgenerational biomarkers for assessing perinatal outcomes, as well as that appropriate medical interventions could improve the outcomes via quantitative changes in mtDNA.

The great earthquake of 11 March 2011 and resulting tsunami caused serious damage to various areas of the Pacific coast in northeast Fukushima, and all the residents faced fears of meltdown of the reactors at the Fukushima Daiichi Nuclear Power Plant. One of the most seriously affected areas was the district of Soso, located in the northeast part of Fukushima prefecture, with 12 municipalities (Soma City, Minamisoma City, Shinchi Town, Namie Town, Futaba Town, Ōkuma Town, Tomioka Town, Naraha To

The combination of population-based biobanking and human genomics provided a novel insight of diversity of ATM gene variants at a population level. For the advancement of precision medicine, such approach will be useful to predict novel pathogenic/likely pathogenic variants in the ATM gene and to establish preventive medical guidelines for certain ATM heterozygotes pertaining to their risk of particular diseases.