Two cases of penis tuberculides are described. Although this disease once used to be comparatively common in Japan, the number of people affected by the disease has recently decreased as the prevalence of tuberculosis has fallen. However, we can still find a few cases in the Japanese literature every year. Outside Japan, we can hardly find reports of this disease, except for a few cases reported under the title of ‘Papulonecrotic tuberculides on the penis’ from Northern European countries. In addition to reporting 2 cases, we summarize clinical features of this disease. Racial predisposition or endemic factors may be related to the tuberculides in such a special site.

A case of systemic scleroderma with peculiar morphaea-like lesions is reported. The patient at first started with typical acrosclerosis, some parts of which later became softened and apparently resumed the appearance of normal skin, so that morphaea-like cutaneous plaques which remained hard, were soft. These changes were surrounded by erythema resembling the ‘lilac ring’ as noted in characteristic active lesions of morphaea.

A case of bullous pemphigoid associated with metastatic squamous cell carcinoma of the skin from the oral cavity, is described. Such an association of these two uncommon entities does not appear to have been reported previously.

Muscle injury was studied to test the hypotheses that maintaining the soleus muscle at a long muscle length during contraction prevents muscle injuries and that the prevention of initial muscle injuries reduces subsequent muscle damage. The rat sciatic nerve was stimulated for 30 min with plantar or dorsal flexion of the foot, and the time course of contraction-induced injuries was examined. The soleus muscle injuries were first classified into one of five types, and the percentages of aberrant sarcomere areas observed in the soleus muscle were then separately quantified by electron microscopy at 0, 1, 6, 12, and 24 h (n = 3) post-stimulation. At a short muscle length (plantar flexion) during contraction, the soleus muscle showed sarcomere hypercontraction (9.8 ± 2.5%, mean ± standard error) and Z-band disarrangement (31.0 ± 4.5%) at 0 h, sarcomere hypercontraction (6.7 ± 1.9%), Z-band disarrangement (28.0 ± 4.9%), and sarcomere hyperstretching (1.3 ± 1.3%) at 1 h, the absence of sarcomere hypercontraction, but Z-band disarrangement (6.7 ± 1.9%) and sarcomere hyperstretching (5.0 ± 1.8%) at 6 h, and myofilament disorganization at 12 and 24 h (5.2 ± 1.5 and 2.5 ± 1.0%, respectively). In contrast, the soleus muscles at a long muscle length (dorsal flexion) during contraction using a self-made brace showed alterations in 1.2-2.4% of sarcomeres at 0 h and afterwards. Desmin disappeared, and α-actinin immunostaining was weaker in areas of sarcomere hypercontraction, whereas dystrophin was always detected along the sarcoplasmic membrane, suggesting that the integrity of the sarcolemma was intact. These results indicate that initial and subsequent muscle injuries were significantly reduced at long muscle length during contraction, probably through the prevention of sarcomere hypercontraction, and that initial muscle injuries rapidly progress to other injuries or normal structure.