[Role of integrated imaging (computerized tomography and echography) in the surgical reconstruction of the external ear]

Three-dimensional Computed Tomography (3DCT) imaging methods of the skull and ribs by axial and contiguous slices allow the selective rendering of the involved structures. The possibilities given by variable threshold ranges allow 12-bit density structures (Hounsfield Units) to be obtained within threshold limits. Imaging has been optimized by shading solids. Such methods, together with US (duplex-Doppler) techniques, offer new diagnostic possibilities relative to the treatment planning of patients with either congenital malformations or acquired abnormalities of the external ear and in the evaluation of associated abnormalities of craniofacial areas. In the reconstruction of the earlap by autograft of modelled rib cartilage, after preparing an expanded otomastoid skin flap, the above methods allowed accurate preoperative planning with consequently significant reduction of surgical time and better clinical results. Six patients with earlap abnormalities (four with microtia due to complete hemifacial microsomia syndrome, one with anotia and one with post-traumatic loss of the earlap) were studied for reconstruction. High-quality 3DCT images of the rib and auricolar cartilage were obtained in real-scale representation (1:1 ratio) the evaluation of the donor site and of the autograft size. Useful pieces of information on the development and vascularization of an expanded otomastoid flap, after gradual and constant expansion, were given by duplex-Doppler US, which allowed easy monitoring in both surgical planning and follow-up.

[PTFEe in the treatment of facial wrinkles]

The first signs of skin aging appear quite early, around 30 years of age, and show as glabella and facial wrinkles particularly pronounced around the eye, lips and nasolabial area. None of these imperfections can be expressively modified through a cervicofacial rhytidectomy (facelift). The use of PTFEe in reconstructive surgery has been established by years of positive experience; therefore, the well known characteristics of such material suggested the idea of extending its use to aesthetic surgery. The corrections performed with this material are carried out mostly as day hospital surgery in local anaesthesia, requiring, however, technical skill to obtain satisfying results.

[PTFE in reconstructive surgery on the face]

The employment of synthetic materials instead of autologous tissues (cartilaginous, adipose tissue, etc.) is already well codified and widely spread: the only restraint to their use is represented by biocompatibility which is not always satisfactory. Prosthesis should be clinically inert and inalterable with time, easy to sterilize, intraoperatively mouldable, and, from the aesthetic point of view, unrecognizable at touch. Since PTFE is widely used in general surgery (vascular prosthesis, aortobifemoral bypass, ect.) we have employed it in plastic surgery obtaining good results in the correction of malar depressions, and in harmonizing the final result of a rhinoplasty or of a labial plasty. All patients showed to well tolerate the material employed without any evident inflammatory reaction and with stable results at long-term follow-up.

Phospholipid – protein molecular interactions. 2. Raman spectroscopic and calorimetric studies of phospholipids – polylysine and phospholipid – histones interactions in model membranes

Dimyristoylphosphatidylcholine (DMPC) – polylysine and DMPC–histones systems have been studied by Raman spectroscopy and differential scanning calorimetry. The results of both techniques indicate that the interactions are mainly confined to the lipid–water interface. The protein fraction of histones giving rise to a partial penetration into the bilayer is not the lysine-rich fraction but rather the non-polar component of the proteins. On the basis of the results obtained, the formation of lipoprotein complexes between histones and DMPC appears to be ruled out.

Raman spectroscopic investigations on conformational changes induced by some phenol derivatives on phospholipid membranes

Some phenol derivatives which uncouple oxidative phosphorylation in mitochondria alter the dipalmitoylphosphatidylcholine membrane structure in the same way that elevating the temperature does. Below the transition temperature, they disorder the membrane gel-phase by inducing the pretransition situation at concentrations within significant biological limits. When the temperature is higher than Tm, their effect on the membrane structure is negligible. The comparison of these phenol derivatives having uncoupling activity with a phenol derivative which does not have such activity demonstrates that the latter does not induce a similar physical effect.