• International Journal of Oral Biology
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• v.31 no.3
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• pp.93-98
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• 2006

Biosynthetic processing of fibrillar procollagens is essential for producing mature collagen monomers that polymerize into fibrils by a self-assembly process. The metalloproteinase ADAMTS-2 is the major enzyme that processes the N-propeptide of type I procollagen in the skin and also of type II and type III procollagens. Mutations in the ADAMTS-2 gene cause dermatospraxis in animals and Ehlers-Danlos syndrome VIIC in humans, both of which are characterized by the accumulation of type I pN-collagen and the formation of abnormal collagen fibrils in the skin. Despite its importance in procollagen processing, little is known about the regulation of ADAMTS-2 expression. Here, we demonstrate that ADAMTS-2 can be regulated by 1,25-dihydroxyvitamin D3, an inducer of type I procollagen synthesis. This steroid hormone induced ADAMTS-2 mRNA ${\sim}3-fold$ in MG-63 human osteosarcoma cells and MC3T3-E1 murine osteoblastic cells. This induction was dose- and time-dependent in MG-63 cells. In contrast, secreted ADAMTS-2 protein was increased only 1.4-fold with 1,25-dihydroxyvitamin D3. Finally, 1,25-dihydroxyvitamin D3 in the presence of ascorbate increased levels of secreted ADAMTS-2 1.9-fold over ascorbate treatment alone, which did not appreciably change ADAMTS-2 expression. These data indicate that the regulation of ADAMTS-2 is coupled with the synthesis of type I procollagen through 1,25-dihydroxyvitamin D3 signaling and may involve translational or posttranslational control.

• Tuberculosis and Respiratory Diseases
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• v.50 no.1
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• pp.122-126
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• 2001

A non-traumatic, spontaneous hemothorax is rare. The most common causes are coagulopathy, due to anticoagulation treatment, and cancers with a metastasis to the pleural surface. Other unusual causes include thoracic endometriosis, ruptured aortic aneurysm, pulmonary arterio-venous malformation, coagulopathy, Osler-Rendeu-Weber syndrome, Ehlers-Danlos syndrome et cetera. A type 1 neurofibromatosis(Von Recklinghausen's disease) is an autosomal dominant disease that is characterized by multiple skin tumors(neurofibroma) and abnormal skin pigmentation(caf$\acute{e}$-au-lait spots). Some are accompanied by vasculopathy, and are present with a spontaneous hemothorax. Such cases are unusual but fatal. We have recently experienced a case where a young male patient with neurofibromatosis initially presented with hypovolemic shock due to a spontaneous hemothorax. Later, aortography revealed that the cause of the hemothorax was a rupture of a pseudoaneurysm of the right internal mammary artery and as a result, an embolization was performed. Here we report this case with a review of the appropriate literature.