Management of severe tip ptosis in closed rhinoplasty: the horizontal columellar strut

BACKGROUND

Tip ptosis is a relatively common nasal deformity, with an incidence as high as 72% in rhinoplasty patients. Different techniques were described for surgical correction of the droopy tip, such as the lateral crural steel, the lateral crural overlay, the tongue-in-groove technique and others. Most authors agreed that an external rhinoplasty approach is necessary for effectively conducting the alar cartilage-modifying techniques mentioned above.

METHODS

In this article we challenge this paradigm and introduce an efficient method for aesthetic correction of severe tip ptosis through an internal rhinoplasty approach. Twenty-three patients with severe ptosis of the nasal tip were operated on by the senior author (MH) between 2000 and 2005 using the described technique. After carrying out the necessary manoeuvres to achieve the desired tip rotation (reduction of cephalic border of alar cartilages, modification of the caudal septum, reduction of upper lateral cartilages), the desired tip position was maintained with the horizontal columellar strut, whose initial operative description appears here.

RESULTS

The desired rotation and projection were maintained in all but three patients over the first year after the surgery. In three patients we observed some loss of tip projection after 1 year. We did not witness complications directly related to the horizontal columellar strut.

CONCLUSION

The horizontal columellar strut is an efficient tool for stabilising the corrected position of a severely ptotic nasal tip. We recommend adding the horizontal columellar strut to the array of available rhinoplasty techniques.

[Ankle chondrocytes are more resistant to Interleukin-1 than chondrocytes derived from the knee]

BACKGROUND

The incidence of degenerative changes and osteoarthritis is lower in the ankle than in the knee joints. This cannot be explained exclusively with differences in anatomy and biomechanical properties of these two synovial joints. Previous studies have indicated distinct differences in the biochemical composition of the extracellular matrix of articular cartilage from knee and ankle joints. The aim of this study was to identify potential metabolic differences between knee and ankle joint chondrocytes using isolated cells to distinguish the secondary effects of the resident extracellular matrix from the primary matrix-independent effects of cellular differentiation.

METHOD

Isolated knee and ankle chondrocytes from the same human donor were cultured in alginate beads and subsequently exposed to a three-day pulse of the catabolic cytokine interleukin-1 (IL-1) as a model of an inflammatory episode. The metabolism of proteoglycans (PG's) was analyzed as expressed changes in 35S-sulfate incorporation into glycosaminoglycans (GAG's).

RESULTS

The presence of IL-1 induced an inhibition of PG synthesis in knee and ankle articular chondrocytes. The 50% inhibitory concentration (IC50) of IL-1 was about 5 times lower for knee than for ankle chondrocytes.

CONCLUSION

Ankle chondrocytes are more resistant to IL-1 induced inhibition of PG synthesis than chondrocytes from the knee.

Reconstruction of pectus excavatum with silicone implants

The pectus excavatum deformity is characterised by a deep depression usually involving the lower one-half to two-thirds of the sternum. The indications for surgery are often aesthetic. Extensive procedures, requiring fracturing and remodelling of the chest wall skeleton are associated with high morbidity and high rate of complications. In this article we describe our renewed experience with reconstruction of mild and moderate pectus excavatum deformities with custom made prefabricated silicone implants. The fabrication of the implant and the surgical technique are described in detail. An excellent aesthetic correction of the deformity was achieved in all of the patients in our series, with high patient satisfaction rate. We conclude that with careful patient selection, artistic implant fabrication and meticulous surgical technique, this approach achieves excellent aesthetic correction with minimal morbidity and a low complication rate and therefore should maintain its place in the armamentarium of surgical techniques for reconstruction of pectus deformities.

[Clinical and genetic study in 22 patients with basal cell nevus syndrome]

BACKGROUND

Nevoid basal cell carcinoma syndrome is an autosomal dominant disorder characterized by developmental abnormalities and cancer predisposition. The PTCH 1 gene, the human homolog of the Drosophila segment polarity gene patched, has been shown to be involved in the development of nevoid basal cell carcinoma syndrome. PTCH 1 is mapped to chromosome 9q22.3. The aim of the present study was to report on clinical and genetic characteristics in patients followed for nevoid basal cell carcinoma syndrome and to compare them to the data in the literature.

PATIENTS AND METHODS

Screening for PTCH 1 mutations was done in 22 patients followed between 1981 and 2003 for clinical suspicion of nevoid basal cell carcinoma syndrome. Clinical and radiological data were reviewed retrospectively from records. Genetic analysis was performed using blood samples after patient informed consent was obtained. When possible, DNA was also analyzed from the parents of patients in whom PTCH 1 mutations were found.

RESULTS

All patients had developed basal cell carcinomas: 45% palmar and plantar pitting, 62% jaw cysts and 66% calcification of falx cerebri. Medulloblastomas and meningiomas were the most common associated tumors. PTCH 1 mutations were identified in 13 patients: 6 familial cases, 3 sporadic cases and for 4 patients, it was not possible to conclude. Nine different new germ-line mutations were identified.

DISCUSSION

Genetic analysis allows molecular confirmation of diagnosis in about half of all patients. Early diagnosis is essential for detection of clinical and radiological manifestations in young patients and for provision of advice concerning protection of the skin from the sunlight.

Microcystic Adnexal Carcinoma: Report of Seven Cases Including One with Lung Metastasis

BACKGROUND

Microcystic adnexal carcinoma (MAC) is a rare cutaneous neoplasm, with a high rate of local recurrences.

OBJECTIVE

A series of MAC was analyzed and compared to previously published cases.

METHODS

Seven cases of MAC were identified in the register of the institution. Medical and pathological records were reviewed.

RESULTS

The primary MAC were located on the face in all patients, and 85% were initially misdiagnosed. The mean follow-up duration was 108 months. The recurrence rate was high: 4 patients developed recurrences. In 3 patients, the course of the disease was severe: one of them developed pathologically proven lung metastasis.

CONCLUSION

The present study and review of the literature confirm the clinically aggressive evolution of MAC and its rare ability to give rise to metastasis. Long-term clinical follow-ups with imaging investigations are mandatory.

E-cadherin loss promotes the initiation of squamous cell carcinoma invasion through modulation of integrin-mediated adhesion

Much remains to be learned about how cell-cell and cell-matrix interactions are coordinated to influence the earliest development of neoplasia. We used novel 3D human tissue reconstructs that mimic premalignant disease in normal epidermis, to directly investigate how loss of E-cadherin function directs conversion to malignant disease. We used a genetically tagged variant of Ha-Ras-transformed human keratinocytes (II-4) expressing dominant-interfering E-cadherin fusion protein (H-2kd-Ecad). These cells were admixed with normal human keratinocytes and tumor cell fate was monitored in 3D reconstructed epidermis upon transplantation to immunodeficient mice. Tumor initiation was suppressed in tissues harboring control- and mock-infected II-4 cells that lost contact with the stromal interface. By contrast, H-2kd-Ecad-expressing cells persisted at this interface, thus enabling incipient tumor cell invasion upon in vivo transplantation. Loss of intercellular adhesion was linked to elevated cell surface expression of α2, α3 and β1 integrins and increased adhesion to laminin-1 and Types I and IV collagen that was blocked with β1-integrin antibodies, suggesting that invasion was linked to initial II-4 cell attachment at the stromal interface. Collectively, these results outline a novel aspect to loss of E-cadherin function that is linked to the mutually interdependent regulation of cell-cell and cell-matrix adhesion and has significant consequences for the conversion of premalignancy to cancer.

Loss of intercellular adhesion activates a transition from low- to high-grade human squamous cell carcinoma

The relationship between loss of intercellular adhesion and the biologic properties of human squamous cell carcinoma is not well understood. We investigated how abrogation of E-cadherin-mediated adhesion influenced the behavior and phenotype of squamous cell carcinoma in 3D human tissues. Cell-cell adhesion was disrupted in early-stage epithelial tumor cells (HaCaT-II-4) through expression of a dominant-negative form of E-cadherin (H-2Kd-Ecad). Three-dimensional human tissue constructs harboring either H-2Kd-Ecad-expressing or control II-4 cells (pBabe, H-2Kd-EcadDeltaC25) were cultured at an air-liquid interface for 8 days and transplanted to nude mice; tumor phenotype was analyzed 2 days and 2 and 4 weeks later. H-2Kd-Ecad-expressing tumors demonstrated a switch to a high-grade aggressive tumor phenotype characterized by poorly differentiated tumor cells that infiltrated throughout the stroma. This high-grade carcinoma revealed elevated cell proliferation in a random pattern, loss of keratin 1 and diffuse deposition of laminin 5 gamma2 chain. When II-4 cell variants were seeded into type I collagen gels as an in vitro assay for cell migration, we found that only E-cadherin-deficient cells detached, migrated as single cells and expressed N-cadherin. Function-blocking studies demonstrated that this migration was matrix metalloproteinase-dependent, as GM-6001 and TIMP-2, but not TIMP-1, could block migration. Gene expression profiles revealed that E-cadherin-deficient II-4 cells demonstrated increased expression of proteases and cell-cell and cell-matrix proteins. These findings showed that loss of E-cadherin-mediated adhesion plays a causal role in the transition from low- to high-grade squamous cell carcinomas and that the absence of E-cadherin is an important prognostic marker in the progression of this disease.

Microenvironmental control of premalignant disease: the role of intercellular adhesion in the progression of squamous cell carcinoma

Interactions between potentially neoplastic cells and their normal neighbors act as an important microenvironmental control during the premalignant, intraepithelial (IE) stage of squamous cell cancer development. Using human three-dimensional (3D) tissue models, it has been shown that such interactions induce a state of IE dormancy in which cancer progression is suppressed. This dormant state can be overcome by altering tissue dynamics in response to the tumor promoter TPA, UV irradiation, decreasing adhesive interactions between tumor cells and adjacent epithelia or enabling tumor cells to interact with basement membrane proteins. This chapter will provide an overview of investigations that have characterized how the tissue microenvironment can regulate the incipient development of squamous cell carcinoma.

E-cadherin suppression accelerates squamous cell carcinoma progression in three-dimensional, human tissue constructs

We studied the link between loss of E-cadherin-mediated adhesion and acquisition of malignant properties in three-dimensional, human tissue constructs that mimicked the initial stages of squamous cell cancer progression. Suppression of E-cadherin expression in early-stage, skin-derived tumor cells (HaCaT-II-4) was induced by cytoplasmic sequestration of beta-catenin upon stable expression of a dominant-negative E-cadherin fusion protein (H-2Kd-Ecad). In monolayer cultures, expression of H-2Kd-Ecad resulted in decreased levels of E-cadherin, redistribution of beta-catenin to the cytoplasm, and complete loss of intercellular adhesion when compared with control II-4 cells. This was accompanied by a 7-fold decrease in beta-catenin-mediated transcription and a 12-fold increase in cell migration. In three-dimensional constructs, E-cadherin-deficient tissues showed disruption of architecture, loss of adherens junctional proteins from cell contacts, and focal tumor cell invasion. Invasion was linked to activation of matrix metalloproteinase (MMP)-mediated degradation of basement membrane in H-2Kd-Ecad-expressing tissue constructs that was blocked by MMP inhibition (GM6001). Quantitative reverse transcription-PCR showed a 2.5-fold increase in MMP-2 and an 8-fold increase in MMP-9 in cells expressing the H-2Kd-Ecad fusion protein when compared with controls, and gel zymography showed increased MMP protein levels. Following surface transplantation of three-dimensional tissues, suppression of E-cadherin expression greatly accelerated tumorigenesis in vivo by inducing a switch to high-grade carcinomas that resulted in a 5-fold increase in tumor size after 4 weeks. Suppression of E-cadherin expression and loss of its function fundamentally modified squamous cell carcinoma progression by activating a highly invasive, aggressive tumor phenotype, whereas maintenance of E-cadherin prevented invasion in vitro and limited tumor progression in vivo.

In vivo transplantation of engineered human skin

Tissue engineering approaches have enabled the development of methodologies that allow long-term, in vivo studies in epidermal biology. This has been accomplished through in vivo transplantation of human epidermal cells fabricated as three-dimensional, skin-equivalents in vitro. The methodologies presented in this chapter describe how skin-equivalent (organotypic) cultures are transplanted to nude mice to generate human skin grafts that normalize their tissue architecture, basement membrane structure and barrier function shortly after grafting. By grafting skin equivalents as composite cultures featuring well-differentiated human epidermis and fibroblasts in collagen gel, transplants are "primed" for accelerated take of grafted tissues. The methods outlined can generate stable, human epidermis that mimics the in vivo tissue.

In vitro fabrication of engineered human skin

In vitro fabrication of human epidermal tissues that mimic the biochemical and morphologic properties of human skin, known as skin-equivalent (organotypic) cultures, has opened new avenues in the study of skin biology. In this chapter, methods for the generation of these tissues from their component parts are described. Conditions for culture of human keratinocytes and fibroblasts that allow optimal growth in skin equivalent cultures are delineated. These cell types are then sequentially combined so that keratinocytes are grown at an air-liquid interface on a contracted collagen gel containing dermal fibroblasts. The methods described enable the generation of human epidermal tissues that show in vivo-like tissue architecture and phenotype.

The importance of conchal resection in correcting the prominent ear

The authors believe that conchal hypertrophy plays a more significant role in ear prominence than has been indicated in the literature. Instead of focusing on the antihelical fold, this otoplasty technique emphasizes chondrocutaneous resection. With even limited resection and resuturing of the cut concha, the antihelix yields to posterior suture placement with a soft, smooth, rounded shape unmarred by any sharp, irregular surfaces.

The central acidic domain of MDM2 is critical in inhibition of retinoblastoma-mediated suppression of E2F and cell growth

Retinoblastoma (Rb) protein is a paradigm of tumor suppressors. Inactivation of Rb plays a critical role in the development of human malignancies. MDM2, an oncogene frequently found amplified and overexpressed in a variety of human tumors and cancers, directly interacts and inhibits the p53 tumor suppressor protein. In addition, MDM2 has been shown to stimulate E2F transactivation activity and promote S-phase entry independent of p53, yet the mechanism of which is still not fully understood. In this study, we demonstrate that MDM2 specifically binds to Rb C-pocket and that the central acidic domain of MDM2 is essential for Rb interaction. In addition, we show that overexpression of MDM2 reduces Rb-E2F complexes in vivo. Moreover, the ectopic expression of the wild type MDM2, but not mutant MDM2 defective in Rb interaction, stimulates E2F transactivation activity and inhibits Rb growth suppression function. Taken together, these results suggest that MDM2-mediated inhibition of Rb likely contributes to MDM2 oncogenic activity.

The Expanded Transposition Flap: Shifting Paradigms Based on Experience Gained from Two Decades of Pediatric Tissue Expansion

The authors present their experience with the design of expanded skin flaps gained over the past two decades in a large series of 995 expanded flap reconstructions performed in 626 operations in 430 patients. The indications for tissue expansion were giant congenital pigmented nevi (72.7 percent), scar contractures (11.2 percent), and a remainder for a variety of congenital and acquired deformities. Surgical strategies were reviewed retrospectively to determine the location in the body where the tissue expansion was performed, the number of procedures required to accomplish the reconstructive goal, and the design of the expanded flap that was used to reconstruct the involved area. Specific points that were noticed included contour deformities (such as webbing, dog-ears, or decreased limb circumference) following flap reconstruction, anatomic distortions (such as distortion of the eyebrow or the distance from the brow to hairline) following reconstruction, final position of the scars in relation to anatomic landmarks, borders of aesthetic units, and relaxed skin tension lines, and the potential for later scar contracture. Careful examination of reconstruction by region of involvement demonstrated significant advantages in the use of expanded transposition flaps over pure advancement. These advantages and the modifications in the design of expanded flaps for each body region are discussed in a series of representative cases. They emphasize the ability of transposition flaps to dissipate tension away from the flap apex and distribute it more proximally, thus redirecting the tension lines so there is less likelihood of anatomic distortion in the reconstructed area. Also, flaps designed in this manner allow improved contour by avoiding webbing, tenting across concavities, and bunching of skin laterally. The authors conclude that restricting the expanded flap design to advancement alone to minimize potential scarring severely limits the reconstructive capabilities of the added tissue and distracts from the surgeon's ability to accomplish the initial reconstructive goal. The cost of additional incisions is worthwhile to achieve better final contour of the reconstructed part, lesser risk of anatomic distortion, better position of the scars, and lowered risk of scar contracture.

Large and Giant Congenital Pigmented Nevi of the Upper Extremity: An Algorithm to Surgical Management

The timing and choice of treatment of congenital giant pigmented nevi continues to evolve under the influence of changing opinions regarding the risk of malignant degeneration and the impact of excision and reconstruction on the affected child. Many studies exist to support a notable enough risk of malignancy to warrant excision, yet other series and pigmented lesion clinics suggest that the risk of malignancy does not warrant the potential scarring and deformity that has followed the surgery necessary to remove these giant lesions. To satisfy both sides in this controversy, we have been challenged to modify our surgical techniques in a manner that minimizes the risk of malignant degeneration and at the same time provides optimal functional and aesthetic outcomes for these complex reconstructions. Thirty consecutive patients with large and giant nevi of the upper extremity were treated over a 23-year period (1979-2002) by the senior author. These patients represent a subset of 259 children (12%) with large or giant congenital pigmented nevi treated and followed during this period of time. In proximal upper extremity lesions, expanded transposition flaps from the upper back and shoulder have effectively eliminated contour defects or circumferential constriction in the upper arm and axilla. An expanded free transverse rectus abdominis musculocutaneous flap has offered a possible avenue for larger lesions (shoulder and upper extremity to below the elbow), and pedicle flaps from the flank (both expanded and nonexpanded) have offered ways of improving the long-term contour in the forearm. Expanded and nonexpanded full-thickness skin grafts were chosen for reconstruction of the hand and the fingers. The authors describe in detail the surgical strategies and the techniques for reconstruction of each region of the upper extremity and then bring these ideas together in an algorithm for assessment and treatment of these challenging lesions.

Abrogation of E-cadherin-mediated adhesion induces tumor cell invasion in human skin-like organotypic culture

The role of cell-cell adhesion in the transition from premalignancy to invasive cancer is not well understood. The purpose of this study was to determine how abrogation of E-cadherin-mediated adhesion influenced early neoplastic progression in tissues that mimic human, premalignant disease. To accomplish this, E-cadherin function was abrogated in a human cell line representing an early stage in the transformation process (HaCaT-II-4 cells) that was grown in three-dimensional, organotypic cultures with intact basement membrane. Before modification, this cell line showed a paucity of cell adhesion structures by ultrastructural and immunohistochemical analysis, whereas immunoblot studies demonstrated that expression and association of E-cadherin and catenins were not diminished when compared with normal keratinocytes. To further reduce functional E-cadherin, II-4 cells were infected with a dominant-negative, recombinant adenovirus, expressing E-cadherin lacking an extracellular domain (AdECadEC). AdECadEC infection resulted in loss of endogenous E-cadherin and completely disrupted II-4 cell adhesion, as seen by loss of beta-catenin from II-4 cell junctions in monolayer culture. In three-dimensional cultures, AdECadEC-infected cells demonstrated disruption of tissue architecture, loss of cell-cell adhesion, and the invasion of individual tumor cells into the stroma. The induction of this invasive phenotype was associated with loss of basement membrane integrity, as seen by degradation of type IV collagen and laminin 5. These studies showed that loss of E-cadherin-mediated adhesion enabled acquisition of an invasive phenotype, suggesting that maintenance of intercellular adhesion and tissue organization plays a crucial part in suppressing the incipient stages of squamous cell cancer progression.

Distraction Osteogenesis of the Mandible With an Internal Bioresorbable Device

Lengthening of the mandible by distraction osteogenesis has been shown to be an effective treatment of hypoplastic mandibles. Use of an internal technique with a bioresorbable distraction device is presented. Mandibular lengthening was performed in seven patients aged 3.2 to 7 years. Six of the patients were diagnosed with craniofacial microsomia, anthe buccal aspect of the mandible, and distraction was started on the second postoperative day at the rate of d one was diagnosed with Nager syndrome. An internal bioresorbable device was placed along 1 mm/d and continued for 17 to 20 days. The distractor screw was maintained for retention for an additional 6 weeks and was then removed. All the patients showed clinical improvement. The postdistraction craniofacial computed tomography scans demonstrated elongation of the mandible with increase in the bony mass. The complications included device failure in one patient. The advantage of this method compared with the internal metal device is that it does not necessitate an additional procedure for device removal.

Connexin 36 in bovine retina: lack of phosphorylation but evidence for association with phosphorylated proteins

In vertebrate retina interneuronal communication through gap junctions is involved in light adaptation and in the transfer of visual information from the rod pathway to the cone pathway. Reports over the last two decades have indicated that these gap junctions are regulated by cyclic nucleotide-dependent protein kinases suggesting that the gap junction proteins, connexins, are phosphorylated. Though all the connexins involved in light adaptation and information transfer from rod to cone pathway are not yet known, connexin 36 has been shown to be definitively involved in the latter process. We have therefore attempted to investigate the cyclic nucleotide-dependent phosphorylation of this connexin in bovine retina. We found several soluble and membrane proteins in bovine retina whose phosphorylation was regulated by cyclic nucleotides. However, no protein of about 36 kDa with cyclic nucleotide-regulated phosphorylation was found in gap junction-enriched membrane preparations. A 36-kDa phosphorylated protein was found in gap junction-enriched membranes phosphorylated in the presence of calcium. However, this protein was not immunoprecipitated by anti-connexin 36 antibodies indicating that it was not connexin 36 in spite of its similarity in molecular weight. Immunoprecipitation did reveal phosphorylated proteins coimmunoprecipitated with connexin 36. Two of these proteins were identified as beta and alpha tubulin subunits. Though cyclic GMP and calcium did not greatly influence the association of these proteins with connexin 36, the results suggest the possibility of connexin 36 associating with other proteins. Together, these observations indicate that interneuronal communication at gap junctions made by connexin 36 may not be regulated by direct phosphorylation of connexin 36, but possibly by phosphorylation of associated proteins.

Analysis of microenvironmental factors contributing to basement membrane assembly and normalized epidermal phenotype

To understand further the role of the dynamic interplay between keratinocytes and stromal components in the regulation of the growth, differentiation, morphogenesis, and basement membrane assembly of human stratified squamous epithelium, we have generated novel, three-dimensional organotypic cultures in which skin keratinocytes were grown in the absence or presence of pre-existing basement membrane components and/or dermal fibroblasts. We found that keratinocytes cultured in the presence of pre-existing basement membrane components and dermal fibroblasts for 9 d showed rapid assembly of basement membrane, as seen by a nearly complete lamina densa, hemidesmosomes, and the polarized, linear distribution of laminin 5 and a6 integrin subunit. Basement membrane assembly was somewhat delayed in the absence of dermal fibroblasts, but did occur at discrete nucleation sites when pre-existing basement membrane components were present. No basement membrane developed in the absence of pre-existing basement membrane components, even in the presence of dermal fibroblasts. Bromodeoxyuridine incorporation studies showed that early keratinocyte growth was independent of mesenchymal support, but by 14 d, both fibroblasts and assembled basement membrane were required to sustain growth. Normalization of keratinocyte differentiation was independent of both dermal fibroblasts and structured basement membrane. These results indicated that epithelial and mesenchymal components play a coordinated role in the generation of structured basement membrane and in the regulation of normalized epithelial growth and tissue architecture in an in vitro model of human skin.

Juvenile xanthogranuloma invading the muscles in the head and neck: clinicopathological case report

Juvenile xanthogranuloma (JXG) is a member of the non-Langerhans cell group of histiocytic proliferative disorders. It typically presents as a solitary, benign, rapidly growing cutaneous tumor that may regress spontaneously. Most cutaneous lesions of JXG occur in the head and neck region of infants and young children. JXG has been documented in many visceral locations including the lung, bone, testis, gastrointestinal tract, kidney, heart, eye, and oral cavity. Intramuscular location is extremely rare. The few intramuscular lesions that have been described involve the trunk, with the musculature of the back involved most frequently. The authors present a patient with juvenile xanthogranuloma on her chin deeply invading the underlying facial muscles. Histopathological analysis confirmed the intramuscular extension. To the authors' knowledge, this is the first detailed clinicopathological report of juvenile xanthogranuloma infiltrating the muscles in the head and neck.