Rhytidectomy and the nasolabial fold.

I describe a technical modification in the Skoog face lift procedure that releases the deep attachments of the SMAS to the muscles of facial expression for maximal mobility of the medial cheek yet elevates the cheek flap as a composite of skin, subcutaneous tissue, and SMAS to enhance skin perfusion. My results with the procedure in 100 patients are analyzed by using functional zones of the nasolabial fold corresponding to underlying musculature and a simple grading system based on preoperative and postoperative photographs. Marked improvement in the nasolabial fold was noted in over 80 percent of patients by 6 and 12 months postoperatively. This effect seemed to last up to 4 years.     

The SMAS and the nasolabial fold.

In a series of histologic sections and clinical and cadaver dissections, the superficial musculoaponeurotic system (SMAS) is seen to become the investing fascia of the zygomaticus major and minor muscles in the medial cheek. The pull on the cheek flap during rhytidectomy is diffused by the attachment of the SMAS to these muscles. I believe that this attachment accounts for the minimal change in the nasolabial crease after a Skoog-type sub-SMAS face lift.     

Correction of the nasolabial fold: extended SMAS dissection with periosteal fixation.

The nasolabial fold has defied satisfactory correction with the face lift operation. This is despite variations of the SMAS technique over the last 20 years. In this study, the nasolabial fold is shown to be part of the overall aging deformity that affects the cheek and perioral region. The key to surgical correction, not previously appreciated, is the complete release of the anterior SMAS from the zygoma and zygomaticus major muscle. This allows a dramatic mobilization of the nasolabial fold without tension. The advanced SMAS is then reattached to the zygomatic periosteum by a series of permanent sutures. Each suture, by its location and direction of lift, corrects one of the four nasolabial regions including the jowl. The relevant anatomy is reviewed and the safety of the procedure is assessed in a personal series of 135 patients. It is concluded that the two principles of this technique, i.e., complete SMAS release and reattachment to the zygoma, safely and effectively achieve a natural-appearing rejuvenation of the cheek and nasolabial fold.     

The nasolabial fold: an attempt at synthesis

There is now enough information on the nasolabial fold to try to synthesize it with other well-known structures, such as the dermal terminations of the facial muscles, the superficial musculoaponeurotic system, and the fat pad. Rest dynamic equilibrium is a good concept to use to understand the nasolabial fold, because the nasolabial fold is not a passive, definitive structure, but an evolutive border whose limits depend on the absence or presence of fibromuscular terminations crossing the superficial musculoaponeurotic system of the cheek. A simple photograph of two men will help illustrate the difference between the convex and the concave nasolabial fold.     

A simple fold with variations: the pacifastin inhibitor family

Members of the pacifastin family are small, approximately 35-residue serine protease inhibitors isolated from arthropod species. Several locust inhibitors exhibit intriguing taxon specificity while others do not. The structural basis of this phenomenon may lie in the different dynamical properties of the proteins originating from different stabilizing interactions. In this study, we identify new members of the family to confirm the universal role of these interactions in the family. Structural investigations show that both the disulfide pattern and the stabilizing interactions are unique among small all-beta proteins.     

Finding the right fold.

Using mutational analysis, three groups have compared the transition states for the folding of two pairs of homologous proteins. The results of these studies suggest that protein folding mechanisms are conserved and are defined primarily by the overall topology of the native structures, as opposed to specific details of the interactions stabilizing these structures.     

Motif-based fold assignment.

Conventional fold recognition techniques rely mainly on the analysis of the entire sequence of a protein. We present an MBA method to improve performance of any conventional sequence-based fold assignment. The method uses sequence motifs, such as those defined in the Prosite database, and the SwissProt annotation of the fold library. When combined with a simple SDP method, the coverage of MBA is comparable to the results obtained with PSI-BLAST. However, the set of the MBA predictions is significantly different from that of PSI-BLAST, leading to a 40% increase of the coverage for the combined MBA/PSI-BLAST method. The MBA approach can be easily adopted to include the results of sequence-independent function prediction methods and alternative motif and annotation databases. The method is available through the web server localized at http://www.doe-mbi.ucla.edu/mba.     

Neuropoietic cytokines in the hematopoietic fold.

Among the molecules that determine the developmental fate of sympathetic neurons from noradrenergic to cholinergic function are two apparently unrelated proteins, cholinergic differentiation factor and ciliary neurotrophic factor (CDF and CNTF, respectively). The present work suggests a structural basis for their functional overlap: sequence pattern-matching and predictive structure analysis contends that CDF and CNTF are homologous and share a common helical framework. An integrated CDF/CNTF profile also reveals similar sequence/structure motifs in a group of hematopoietic cytokines composed of granulocyte colony-stimulating factor, interleukin-6, and a novel factor called oncostatin M; a more distant relationship is indicated with interleukin-3 and interferons-alpha/beta. Evolutionary ties between neuropoietic and hematopoietic cytokines predict a distinctive tertiary architecture for the uncharacterized CDF and CNTF receptors. The intertwined cytokine/receptor networks signal a closer relationship between the molecular mechanisms underlying neuro- and hematopoiesis.     

Evaluation of a technique designed to correct nasolabial folds.

This is a long-term follow-up of correction of nasolabial folds in conjunction with face lift that was first published in 1987. In the last 200 face lifts, nasolabial lipectomy has been carried out in 90 percent. Refinements and extensions of the procedure are also described with case illustrations.