A novel multifunctional microneedle patch for synergistic photothermal- gas therapy against maxillofacial malignant melanoma and associated skin defects.

Considering the high recrudescence and the long-lasting unhealed large-sized wound that affect the aesthetics and cause dysfunction after resection of maxillofacial malignant skin tumors, a groundbreaking strategy is urgently needed. Photothermal therapy (PTT), which has become a complementary treatment of tumors, however, is powerless in tissue defect regeneration. Therefore, a novel multifunctional sodium nitroprusside and Fe2+ ions loaded microneedles (SNP-Fe@MNs) platform was fabricated by accomplishing desirable NIR-responsive photothermal effect while burst releasing nitric oxide (NO) after the ultraviolet radiation for the ablation of melanoma. Moreover, the steady releasing of NO in the long term by the platform can exert its angiogenic effects via upregulating multiple related pathways to promote tissue regeneration. Thus, the therapeutic dilemma caused by postoperative maxillofacial skin malignancies could be conquered through promoting tumor cell apoptosis via synergistic PTT-gas therapy and subsequent regeneration process in one step. The bio-application of SNP-Fe@MNs could be further popularized based on its ideal bioactivity and appealing features as a strategy for synergistic therapy of other tumors occurred in skin.

Preparation and Characterization of Polysaccharide-Based Hydrogels for Cutaneous Wound Healing.

Natural hydrogels are growing in interest as a priority for wound healing. Plant polysaccharides have a variety of biological pharmacological activities, and chitosan hydrogels have proven strong antimicrobial effects, but hydrogels prepared with polysaccharides alone have certain deficiencies. Polysaccharides from flowers of Lonicera japonica Thunb. (LP) and the aerial parts of Mentha canadensis L. (MP) were extracted and oxidized by sodium periodate (NaIO4) and then cross-linked with oxidized-carboxymethylated chitosan (O-CCS) to develop oxidized plant- polysaccharides-chitosan hydrogels (OPHs). SEM observation showed that OPHs had porous interior structures with interconnecting pores. The OPHs showed good swelling, water-retention ability, blood coagulation, cytocompatibility properties, and low cytotoxicity (classed as grade 1 according to United States Pharmacopoeia), which met the requirements for wound dressings. Then the cutaneous wound-healing effect was evaluated in BALB/C mice model, after 7 days treatment, the wound-closure rate of OPHs groups were all greater than 50%, and after 14 days, all were greater than 90%, while the value of the control group was only 72.6%. Of them, OPH-2 and OPH-3 were more favorable to the wound-healing process, as the promotion was more significant. The plant polysaccharides and CS-based hydrogel should be a candidate for cutaneous wound dressings.

Dynamic Closing Method Using Elasticity for Skin Defect / 대한정형외과학회잡지

Skin defects unable to close by primary intention have caused many difficulties. Complex surgical interventions such as repetitive debridements, skin graft, or flap have been performed as therapeutic methods. Recently, new techniques for the skin closure based on the stretching property, elasticity or stress relaxation, have been introduced. This biomechanical property exhibits that the force required to keep the skin at a stretched length decreases over time. As the skin is stretching, the convoluted collagen fibers in dermis are straighten and become a line in the direction of stretching force. Fifteen cases of skin defects associated with fracture were closed by a new dynamic closing method at Department of Orthopaedic Surgery, Yonsei University College of Medicine. Two spinal needles were inserted into dermis along the wound margins on each side in order to distribute the even tension. The wound margins were approximated by suture wires engaged with the needles. We have experienced successful results using new stretch closing method in fracture with skin defect. It is confirmed that this method is rapid, simple, cost-effective, cosmetic, and safe way to close the skin defect and shortens hospital stay.

New Technique of Plastic Reconstruction Using Scrotal Skin Pedicle Graft in Penile Skin Defect / 대한비뇨기과학회지

A new technique of plastic reconstruction of penile skin using scrotal skin pedicle graft was devised This technique was applied in 6 patients who were admitted to the Department of Urology, Korea University Hospital during the period of 5 years and 6 months from January 1974 to June 1979 and the results were excellent in all cases. The primary causes of penile skin defect in these patients were injection of paraffin into the subcutaneous tissues of the penile shaft(4 Pts.) and tissue necrosis resulted from infiltration of local anesthetics for performing circumcision (2 Pts.). The procedure was as follows: 1st stage; With the patient in supine position, under general orspinal anesthesia, the removal of paraffin or fibrotic tissues and necrotic tissues were carried out After the length of penile skin defect was measured and the same length was applied in making three parallel transverse incisions over the scrotal skin and the skin between these incisions was undermined to from two tunnels underneath. The penis was drawn downward through the proximal tunnel to cover the denuded area over the dorsal side of the penis and the glans was exposed. Both the proximal and distal borders of the proximal tunnel were approximated to healthy skin borders of dorsal aspect of the penis. The scrotal skin flap forming distal tunnel was then reversed inside out inwardly and upwardly and approximated the proximal and distal borders with healthy skin borders of distal and proximal borders of ventral aspect of the penis so that the ventral denuded area of the penis could be covered. Then the denuded scrotal skin was closed by approximation of remained scrotal skin edges. Sutures. were carried out in interrupted manner with 4-O Nylon except the ventral side of proximal portion of the penis and closure of the scrotal skin, where 3-0 catgut were used. 2nd stage; After healing had taken place the penis was freed by simple dissection of two lateral pediclcs from the scrotum under local anesthesia. Then simple closure was performed on every dissected borders. The advantages of this technique are as follows: 1. Indwelling of urethral catheter or urinary diversion such as suprapubic cystostomy isnot necesssry in first stage operand and the patient can void urine without difficulty. 2. No discomfort or pain is complained on erection of the penis because the penis is lifted away from the scrotum by the reversed scrotal skin flap. 3. The second stage of this operation is so simple that the procedure is performed under local anesthesia. 4. There isono danger of urethral injury in second stage operation