ABSTRACT-A variety of different isoforms of voltage-sensitive Na+ channels have now been identified. The recent three-dimensional analysis of Na + channels has unveiled a unique and unexpected structure of the Na + channel protein. Na + channels can be classified into two categories on the basis of their amino acid sequence, NaV1 isoforms currently comprising nine highly homologous clones and NaX that possesses structure diverging from Na V 1, especially in several critical functional motifs. Although the functional role of Na V 1 isoforms is primarily to form an action potential upstroke in excitable cells, recent biophysical studies indicate that some of the Na V 1 isoforms can also influence subthreshold electrical activity through persistent or resurgent Na + currents. Na V 1.8 and Na V 1.9 contain an amino acid sequence common to tetrodotoxin resistant Na + channels and are localized in peripheral nociceptors. Recent patch-clamp experiments on dorsal root ganglion neurons from Na V 1.8-knock-out mice unveiled an additional tetrodotoxin-resistant Na + current. The demonstration of its dependence on Na V 1.9 provides evidence for a specialized role of Na V 1.9, together with NaV1.8, in pain sensation. Although NaX has not been successfully expressed in an exogenous system, recent investigations using relevant native tissues combined with gene-targeting have disclosed their unique "concentration"-sensitive but not voltage-sensitive roles. In this context, these emerging views of novel functions mediated by different types of Na + channels are reviewed, to give a perspective for future research on the expanding family of Na + channel clones.

No abstract

Spinal angiolipoma is a rare benign tumor. In the past, authors classified spinal lipomas and angiolipoma together, but now angiolipomas are considered a separate entity from lipomas. The majority of spinal angiolipomas are of the noninfiltrating epidural type, but some are of the infiltrating type including our case and a few cases are intramedullary. Infiltrating angiolipomas extend into the bony compartment of the vertebral column or the thoracic cavity. We experienced a case of epidural angiolipoma infiltrating into the Th3 vertebral body.A 65 year-old male experienced difficulty in controlling his lower limbs. MRI revealed a spindle mass at the level of Th2 to Th4. The lesion was isointense on T1-weighted image and hyperintense on T2-weighted image. After Gd-DTPA, it was enhanced.Resecting the tumor by osteoplastic laminectomy improved the clinical symptoms.

We carried out a study on the prophylaxis of postoperative pulmonary embolism (PE). We used heparin after operation in high risk PE patients, but four patients developed PE.We concluded that appropriate plophylaxis is necessary to prevent PE.

No abstract