Reconstructive procedures in the head and neck region use a wide range of flaps for defect closure. The methods range from local, mostly myocutaneous flaps and skin grafts to free microsurgical flaps. To ensure a satisfactory functional and aesthetic result, good texture and color of the flap are always essential. Moreover, the donor-site defect needs to be reduced, with no resulting functional or aesthetic impairment. We have found that the shoulder is a region providing an optimum skin texture match to the neck and face. In cadaver dissection, a vascular pedicle extending from the transversal cervical artery with two accompanying veins was found to vascularize a defined region around the shoulder cap. In line with these findings, the previously described fasciocutaneous island flap, nourished by the supraclavicular artery, was developed further and used purely as a subcutaneously tunneled island flap. The tunneling maneuver significantly improves the donor site by reducing scarring. The flap is characterized by a long subcutaneous pedicle of up to 20 cm. The pivot point is in the supraclavicular region and allows the flap to be used in the upper chest, neck, chin, and cheek. In this article, we introduce the anatomic features and present clinical cases underlining the surgical possibilities of the flap in reconstructive procedures with expanded indications.
Cells in culture undergo replicative senescence. In this study, we analyzed functional, genetic and epigenetic sequels of long-term culture in human mesenchymal stem cells (MSC). Already within early passages the fibroblastoid colonyforming unit (CFU-f) frequency and the differentiation potential of MSC declined significantly. Relevant chromosomal aberrations were not detected by karyotyping and SNP-microarrays. Subsequently, we have compared DNA-methylation profiles with the Infinium HumanMethylation27 Bead Array and the profiles differed markedly in MSC derived from adipose tissue and bone marrow. Notably, all MSC revealed highly consistent senescence-associated modifications at specific CpG sites. These DNA-methylation changes correlated with histone marks of previously published data sets, such as trimethylation of H3K9, H3K27 and EZH2 targets. Taken together, culture expansion of MSC has profound functional implications - these are hardly reflected by genomic instability but they are associated with highly reproducible DNA-methylation changes which correlate with repressive histone marks. Therefore replicative senescence seems to be epigenetically controlled.
Mentosternal contractures represent a surgical challenge to the plastic and reconstructive surgeon. We add the supraclavicular artery island flap to the armamentarium of surgical procedures to improve the function and cosmesis of disfigured patients. Since July of 1994, the supraclavicular artery island flap has been used at our institution for releasing postburn mentosternal contractures in eight patients. The flap was planned to be 4 to 10 cm in width and 20 to 30 cm in length with the supraclavicular vessels running axially. All donor defects could be closed primarily without significant postoperative complications in seven of the eight patients. All flaps healed primarily, achieving a good functional result by complete removal of contracting scar tissue for all patients; one donor site healed by secondary intention. We found the supraclavicular artery island flap both reliable and safe for immediate resurfacing after resection of cervical scars. The anatomy, operative procedure, and postoperative results of the supraclavicular artery island flap are outlined in this paper.
The goal of this study was the development of a bioartificial nerve guide to induce axonal regeneration in the peripheral nervous system (PNS). In this in vitro study, the ability of a novel, 3-dimensional (3D), highly oriented, cross-linked porcine collagen scaffold to promote directed axonal growth has been studied. Collagen nerve guides with longitudinal guidance channels were manufactured using a series of chemical and mechanical treatments with a patented unidirectional freezing process, followed by freeze-drying (pore sizes 20-50 microm). Hemisected rat dorsal root ganglia (DRG) were positioned such that neural and non-neural elements could migrate into the collagen scaffold. After 21 days, S100-positive Schwann cells (SCs) migrated into the scaffold and aligned within the guidance channels in a columnar fashion, resembling "Bands of Büngner." Neurofilament-positive axons (mean length +/- SD 756 microm +/- 318 microm, maximum 1496 microm) from DRG neurons entered the scaffold where the growth within the guidance channels was closely associated with the oriented SCs. This study confirmed the importance of SCs in the regeneration process (neurotrophic theory). The alignment of SCs within the guidance channels supported directional axonal growth (contact guidance theory). The microstructural properties of the scaffold (open, porous, longitudinal pore channels) and the in vitro data after DRG loading (axonal regeneration along migrated and columnar-aligned SCs resembling "Band of Büngner") suggest that this novel oriented 3D collagen scaffold serves as a basis for future experimental regeneration studies in the PNS.
Rationale: Human skin contains photolabile nitric oxide derivates like nitrite and S-nitroso thiols, which after UVA irradiation, decompose and lead to the formation of vasoactive NO. Objective: Here, we investigated whether whole body UVA irradiation influences the blood pressure of healthy volunteers because of cutaneous nonenzymatic NO formation. Methods and Results: As detected by chemoluminescence detection or by electron paramagnetic resonance spectroscopy in vitro with human skin specimens, UVA illumination (25 J/cm 2 ) significantly increased the intradermal levels of free NO. In addition, UVA enhanced dermal S-nitrosothiols 2.3-fold, and the subfraction of dermal S-nitrosoalbumin 2.9-fold. In vivo, in healthy volunteers creamed with a skin cream containing isotopically labeled 15 N-nitrite, whole body UVA irradiation (20 J/cm 2 ) induced significant levels of 15 N-labeled S-nitrosothiols in the blood plasma of light exposed subjects, as detected by cavity leak out spectroscopy. Furthermore, whole body UVA irradiation caused a rapid, significant decrease, lasting up to 60 minutes, in systolic and diastolic blood pressure of healthy volunteers by 11؎2% at 30 minutes after UVA exposure. The decrease in blood pressure strongly correlated (R
BackgroundHidradenitis suppurativa (HS) is a chronic inflammatory cutaneous disorder that involves the infundibular terminal follicles in areas rich of apocrine glands. It can be associated with fistulating sinus, scarring and abscesses formation. Hidradenitis suppurativa is a challenging aspect and requires a proper treatment plan which may involve different specialties. We present herein the option of surgical treatment involving wide surgical excision and methods of reconstruction as well as the rate of recurrence. Furthermore, review of the literature regarding surgical treatment of hidradenitis suppurativa is provided.MethodsA retrospective analysis reviewed 50 operative procedures for 32 patients in 5 anatomical sites. These anatomical sites have been divided to 23 sites involving the axilla, 17 sites involving the inguinal region and 8 sites involving the perianal/perineal area, 1 site involving the gluteal region and 1 site involving the trunk region.ResultsTwenty six patients (81, 25 %) showed no recurrence after surgery and the average time of hospital stay period was 5 days. Recurrence was observed only in 6 patients (18, 75 %).ConclusionElimination of the acute inflammatory process should occur in advance, including the use of antibiotics and minor surgeries such as abscess drainage with proper irrigations. After stabilizing the acute phase, wide surgical excision is recommended. Herein, planning of surgical reconstruction should be initiated to achieve the best outcome and consequently decreasing the risk of recurrence and complications after surgery.
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