and Relevance: Severe necrosis and mild fibrosis were observed in the liver and forelimb skeletal muscles. Based on histological analysis, we diagnosed iron overload myopathy by secondary hemochromatosis. Secondary hemochromatosis with severe muscle atrophy and myositis is very rare, and this is the first report of iron-overload myopathy in a dog.

and Relevance: Severe necrosis and mild fibrosis were observed in the liver and forelimb skeletal muscles. Based on histological analysis, we diagnosed iron overload myopathy by secondary hemochromatosis. Secondary hemochromatosis with severe muscle atrophy and myositis is very rare, and this is the first report of iron-overload myopathy in a dog.

and Relevance: Severe necrosis and mild fibrosis were observed in the liver and forelimb skeletal muscles. Based on histological analysis, we diagnosed iron overload myopathy by secondary hemochromatosis. Secondary hemochromatosis with severe muscle atrophy and myositis is very rare, and this is the first report of iron-overload myopathy in a dog.

and Relevance: Severe necrosis and mild fibrosis were observed in the liver and forelimb skeletal muscles. Based on histological analysis, we diagnosed iron overload myopathy by secondary hemochromatosis. Secondary hemochromatosis with severe muscle atrophy and myositis is very rare, and this is the first report of iron-overload myopathy in a dog.

Background: Longitudinal melanonychia (LM) is a common clinical finding. Most cases of LM are benign, and a waitand-see approach is preferred in the management of this condition. Nevertheless, it is important for clinicians to distinguish subungual melanoma (SUM) from other benign LMs. Objective: To evaluate the demographic and clinicopathologic characteristics of LM in the Korean population and to identify the predictor of SUM against other benign conditions. Methods: This was a single-center retrospective cohort study including patients who underwent nail biopsy for LM from January 2000 to May 2019. To identify the predictor of SUM, receiver operating characteristic (ROC) analyses was performed. Results: A total of 68 cases of biopsy-proven LM were included in the analysis. Among the 68 cases, 8 were SUM. In univariable analysis, patients diagnosed with SUM were older (p=0.035) and had a longer disease duration (p=0.004).They also showed multicolor pigmentation of LM (p=0.022),a larger width of LM (p＜0.001), and associated nail plate dystrophy (p=0.010) than patients diagnosed with benign conditions. In multivariable logistic regression, width of LM showed statistical significance (odds ratio, 1.083; 95% confidence interval, 1.018∼1.153). ROC analysis suggested that an LM width ＞28% of the whole nail was the predictor of SUM (area under the curve=0.883; p＜0.001). Conclusion SUM has distinct demographic and clinical features. The width of LM can predict SUM against other benign LMs.

Background: Female-pattern hair loss (FPHL) is a common hair loss disorder in women. The various treatments include topical minoxidil and 17α-estradiol, as well as oral anti-androgens. However, the clinical efficacy of 5α -reductase inhibitors remains controversial. Objective: We evaluated the clinical utility of dutasteride in FPHL patients and how dutasteride promotes hair growth. Methods: We evaluated hair follicle density and thickness before and after oral dutasteride treatment in 24 patients with FPHL. We measured β-catenin activity in primary cultures of human dermal papilla cells (DPCs) using the TOP Flash reporter assay and Western blotting. The expression levels of genes promoting hair growth were quantitatively assessed using quantitative polymerase chain reaction (Q-PCR). Results: The mean vertex hair density increased significantly from 67±14 to 76±13/cm2 (p=0.001) and the mean occipital hair density increased from 89±11 to 94±13/cm2 (p=0.012) after dutasteride treatment. However, the mean hair thickness did not increase. When DPCs were treated with dutasteride, TOP Flash activity increased in a dose-dependent manner, and the protein level of non-phosphorylated (active) β-catenin also increased. The mRNA level of vascular endothelial growth factor increased, but the mRNA levels of the keratinocyte growth factor, insulin growth factor-1, and Noggin were not affected by dutasteride. Conclusion This study shows a novel mechanism of dutasteride in promoting hair growth and provides support for the possible clinical application of 5α-reductase inhibitors for the treatment of FPHL.