Protective Effect of PKC Affecting Gliotoxin-induced Cytotoxicity in Rat Smooth Muscle Cells / 대한해부학회지

Aspergillus funigatus and other pathogenic fungi synthesize a toxic epidithi-odiopiperzine (ETP) metabolite, namely gliotoxin. Gliotoxin commonly react with sulfhydryl groups, and then, forms hydrogen peroxide. These fungal toxins induce apoptotic cell death in various cells. Apoptosis induced by gliotoxin need calcium. Effect of calcium preconditioning was not reported in gliotoxin-induced apoptosis. To examine the effect of protein kinase C (PKC) and calcium which was regulate caspase-3, PKC and calcium preconditioning before gliotoxin treatment, apoptotic agents such as bcl-2 family, caspase-3 and DNA fragmentation in A7r5 cell line from rat smooth muscle cell were studied. These results showed that gliotoxin induces the expression of bad of bcl-2 family, caspase-3 activation and DNA fragmentation in A7r5 cells. Gliotoxin treatment followed by calcium and PKC preconditioning suppress the Bad of bcl-2 family, and inhibited caspase-3 activation, respectively. These results suggest that PKC and calcium preconditioning protect the gliotoxin-induced apoptosis, through the protection of pro-apoptotic bcl-2 family in A7r5 cells.

Reduction mandibular angleplasty assisted by c-arm fluoroscopy

The prominent mandibular angle is one of the disfiguring features in the Oriental, commonly seen and considered to be unattractive. Because it gives a square and muscular facial appearance, its surgical correction is dine frequently as a modality of facial contouring surgery in the Oriental. The reduction mandibular angleplasty is not a simple surgical technique for the unexperienced surgeon. We adopted C-arm fluoroscopy as a method of identifying the osteotomy line for the beginners. The reduction mandibular angleplasties assisted by C-arm fluoroscopy were performed in 9 patients, providing symmetric and satisfactory results. Now we are sure that the reduction mandibular angleplasty assisted by C-arm fluoroscopy can be an accurate and safe method for the unexperienced surgeon, especially the patient with deep-seated prominent mandibular angle.

Clinical experience of ear elevation after reconstruction of microtia

The basic technique for total reconstruction of the microtia was established by Tanzer, who utilized autologous rib cartilages for constructing the auricular framework. In order to decrease the number of surgical stages and to achieve maximal convolution, we employed a surgical procedure with simultaneous three layered costal cartilage grafting for the high profiled auricle, concha formation and lobule rotation. However, we performed ear elevation as an additional procedure for some patients who had decreased helical height due to absorption of cartilage framework or postoperative trauma and who had wanted to wear the spectacles or to have more natural appearance of auriculocephalic sulcus. From August 1988 to October 1997 we had performed surgeries for the ear elevation of 58 patients in 177 patients with total ear reconstruction, using various elevation methods; skin graft, local flap, and local with costal cartilage block. When the ear elevation was performed with skin graft, postoperative contraction of the grafted skin was inevitable. In cases with two skin flaps, it was difficult to stabilize and maintain the correct projection of the constructed ear. So we elevated the reconstructed ear by utilizing a costal cartilage block, two skin flaps to cover the posterior region and skin graft. We conclude that the local flap with costal cartilage block is one of the most favorable methods in ear elevation which can maintain the adequate projection and make natural looking auriculocephalic sulcus.

Tragus formation by chondrocutaneous flap in reconstruction of microtia

Tanzer reported microtia reconstruction using autogenous costal cartilage, thereafter so many plastic surgeons have tried various modification to get further refinement of reconstructed auricle. But the multiple stages of ear reconstruction required prolonged hospitalization and cost. In order to decrease the number of surgical stages and for the maximal convolution, we have employed a surgical procedure with three layered costal cartilage graft for the high profile auricle, concha formation and lobule transposition at the same time. However, it has still been difficult to reconstruct the tragus in cases of microtia that lack such component. We reconstructed the tragus using part of the microtic ear in addition to our above procedure simultaneously. This procedure is started with transposition of the lower two-thirds of the microtic ear to make lobule and then the upper third of the microtic ear is elevated as a chondrocutanenous flap which is then transposed 120-180degree C downwards to reposition at the area anterior to the conchal cavity. Using this technique, we have reconstructed 28 microtic ears. Adequate positioning of the auricle and tragus have been achieved and a more natural auricle obtained.