Quantitative and qualitative mutational impact of ionizing radiation on normal cells.

The comprehensive genomic impact of ionizing radiation (IR), a carcinogen, on healthy somatic cells remains unclear. Using large-scale whole-genome sequencing (WGS) of clones expanded from irradiated murine and human single cells, we revealed that IR induces a characteristic spectrum of short insertions or deletions (indels) and structural variations (SVs), including balanced inversions, translocations, composite SVs (deletion-insertion, deletion-inversion, and deletion-translocation composites), and complex genomic rearrangements (CGRs), including chromoplexy, chromothripsis, and SV by breakage-fusion-bridge cycles. Our findings suggest that 1 Gy IR exposure causes an average of 2.33 mutational events per Gb genome, comprising 2.15 indels, 0.17 SVs, and 0.01 CGRs, despite a high level of inter-cellular stochasticity. The mutational burden was dependent on total irradiation dose, regardless of dose rate or cell type. The findings were further validated in IR-induced secondary cancers and single cells without clonalization. Overall, our study highlights a comprehensive and clear picture of IR effects on normal mammalian genomes.

Successful treatment of xanthoma disseminatum with pulsed dye laser: A case report.

Xanthoma disseminatum is a rare form of non-Langerhans cell histiocytosis with limited treatment options due to its unknown aetiology and diffuse skin lesions. This case report presents the successful treatment of a 31-year-old male with severe pan-facial xanthoma disseminatum lesions following a facial burn and traumatic brain injury resulting from a car accident. After 5 sessions of monthly pulsed dye laser treatment, there was a clinically significant reduction in the lesions. Over the course of 3 years, the patient underwent a series of monthly pulsed dye laser treatments, and the lesions were almost cleared. These findings suggest that pulsed dye laser therapy may offer an effective treatment option for managing xanthoma disseminatum. This is the first report on use of the pulsed dye laser for treatment of xanthoma disseminatum.

Successful Treatment of Recurrent Earlobe Keloid Through Removal of Concealed Underlying Epidermoid Cysts: A Case Report.

In modern clinical practice, earlobe keloids demonstrate a high cure rate through surgical intervention and suitable adjuvant therapies. Furthermore, the concurrence of keloids and epidermoid cysts is uncommon, potentially attributed to the lack of skin appendages within keloid tissue. This case report presents the successful treatment of a recurrent earlobe keloid through the removal of concealed underlying epidermoid cysts. The lesion recurred even after the second excision and proper adjuvant treatments. It was finally stabilized following the removal of epidermoid cysts within the earlobe at the third surgical procedure. These findings emphasize the importance of identifying underlying conditions associated with keloids and addressing inflammation, as these factors significantly influence treatment outcomes and resistance.

Longitudinal intravital imaging of cerebral microinfarction reveals a dynamic astrocyte reaction leading to glial scar formation.

Cerebral microinfarct increases the risk of dementia. But how microscopic cerebrovascular disruption affects the brain tissue in cellular-level are mostly unknown. Herein, with a longitudinal intravital imaging, we serially visualized in vivo dynamic cellular-level changes in astrocyte, pericyte and neuron as well as microvascular integrity after the induction of cerebral microinfarction for 1 month in mice. At day 2-3, it revealed a localized edema with acute astrocyte loss, neuronal death, impaired pericyte-vessel coverage and extravascular leakage of 3 kDa dextran (but not 2 MDa dextran) indicating microinfarction-related blood-brain barrier (BBB) dysfunction for small molecules. At day 5, the local edema disappeared with the partial restoration of microcirculation and recovery of pericyte-vessel coverage and BBB integrity. But brain tissue continued to shrink with persisted loss of astrocyte and neuron in microinfarct until 30 days, resulting in a collagen-rich fibrous scar surrounding the microinfarct. Notably, reactive astrocytes expressing glial fibrillary acidic protein (GFAP) appeared at the peri-infarct area early at day 2 and thereafter accumulated in the peri-infarct until 30 days, inducing glial scar formation in cerebral cortex. Our longitudinal intravital imaging of serial microscopic neurovascular pathophysiology in cerebral microinfarction newly revealed that astrocytes are critically susceptible to the acute microinfarction and their reactive response leads to the fibrous glial scar formation.

Elasticizing tissues for reversible shape transformation and accelerated molecular labeling.

We developed entangled link-augmented stretchable tissue-hydrogel (ELAST), a technology that transforms tissues into elastic hydrogels to enhance macromolecular accessibility and mechanical stability simultaneously. ELASTicized tissues are highly stretchable and compressible, which enables reversible shape transformation and faster delivery of probes into intact tissue specimens via mechanical thinning. This universal platform may facilitate rapid and scalable molecular phenotyping of large-scale biological systems, such as human organs.

The First Reported Case of Fibrous Hamartoma of Infancy with Hyperhidrosis and Hypertrichosis in Korea.

Fibrous hamartoma of infancy (FHI) is a rare entity with a benign nature. The typical clinical features are a single, slowly growing, painless mass on the trunk that appears within the first 2 years of life. We report a 13-month-old boy who presented with a plaque on the lower back since 4 months of age. The plaque had gradually become larger and firm, and hyperhidrosis and hypertrichosis were noticed. No visible connection between the spinal cord and the lesion was found in radiologic studies, indicating a disease other than spinal dysraphism. Histopathological findings showed well-defined fibrous trabeculae, mature adipose tissue, and primitive mesenchymal cells, all consistent with FHI. This is the first case of FHI presenting with hyperhidrosis and hypertrichosis reported in Korea.