RESUMO
The fibrous tumors of the pleura are rare primary tumors, accounting for 5% of malignant pleural neoplasms, which generally originate from sub-mesothelial mesenchymal tissue of the visceral pleura. These tumours generally exhibit clinical benign behavior although 12% of solitary fibrous tumors can be malignant and have worse outcomes. These tumors are considered "giant" when the lesion > 15 cm. Surgical treatment is the best choice for both benign and malignant neoplasms. We retrospectively analyzed the main case series of giant fibrous tumors of the pleura. In addition we report our experience of a 76-year-old woman treated by pre-surgical embolization involving implantation of vascular plugs. Surgery was successfully carried out without complications; imaging and functional assessment 6 months post intervention demonstrated both the absence of recurrence and improvement of lung function parameters.
RESUMO
We investigated the effects of cyclic stretch on vascular smooth muscle cell (VSMC) alignment and potential overlap of signaling modalities with stretch-induced proliferation. VSMC were subjected to graded stretch (1 Hz at 100-124% of resting length) for 48 h. Graded stretch resulted in graded VSMC alignment from a minimum of completely random orientation to a maximum of ~80-85 degrees to the stretch vector. Alignment was reversible within 48 h of stretch cessation and independent of signaling modalities mediating stretch-induced proliferation: modulation of IGF-1, MAPK, phosphatidylinositol 3-kinase, tyrosine kinase, and stretch-activated calcium channels did not affect alignment. Nitric oxide (NO) synthase (NOS) blockade uncoupled alignment. Neither the NO donor, cytokine-induced NOS activity, nor L-citrulline affected alignment, but inhibited VSMC proliferation. Therefore, stretch-induced proliferation and alignment are differentially regulated, with NO a common signaling molecule for both. Targeting NOS in states such as restenosis and hypertension may prove to be beneficial.
