Optimal blue light irradiation conditions for the treatment of acne vulgaris in a mouse model.

BACKGROUND: Although blue light is one of the therapeutic approaches used to treat acne vulgaris (AV), there is no consensus on its effectiveness. As a result, it is not recommended in the major acne vulgaris treatment guidelines. OBJECTIVE: The goal of this study was to look into the mechanism, safety, and efficacy of blue light therapy. We achieved this by examining the pathological response, inflammation, and depth of light penetration in a mouse model of cystic AV. METHODS: The aims of the study were addressed by exposing the mice to light with a wavelength of 415 nm under four different irradiation conditions. The exposure was done for five consecutive days followed by a no irradiation period of 72 h. RESULTS: Blue light treatment was most effective when irradiation was performed at 100 mW/cm2 for 20 min for five consecutive days. Inflammatory responses emerged 72 h after the final irradiation dose was administered. These responses were not associated with apoptosis as cleaved caspase-3 staining revealed no significant increases in apoptosis in the skin under any of the tested conditions. Blue light reached the superficial layer of the acne cyst at 5% of the total irradiation power and was attenuated by half for every 50 µm of progress through the cyst. CONCLUSION: In conclusion, blue light could control severe dermatologic inflammatory responses; therefore, it can be used to irradiate AV with high inflammation levels on a daily basis until improvement is observed. In addition, porphyrin, a metabolite of Cutibacterium acnes, and reactive oxygen species generated by the surrounding skin tissue may have essential roles in AV treatment.

Three-dimensional scanner with a modified evaluation method for measuring hand edema subtitle: an idea for accurate evaluation and preliminary fundamental and clinical validation.

Acute hand edema often results in loss of fine hand motor activities, especially without appropriate care. There is still no reliable and easy to use method to measure hand edema. In this study, we tested a handheld three-dimensional (3D) scanner on plastic male and female hand models using a whole hand measuring method (WM) and a modified method (MM) which excluded fingers. We evaluated the intra-rater reliability and inter-rater reliability and compared the measured volumes to computed tomography (CT) findings. Statistical analysis showed that the 3D scan method was valid and reliable for both WM and MM methods. In WM, intra-rater and inter-rater reliability were 0.97 and 0.84, with 95% confidence interval (CI) of 0.87-1.00 and 0.61-0.94, respectively. In MM, intra-rater and inter-rater reliability were 0.96 and 0.83, with 95% CI of 0.84-1.00 and 0.61-0.94, respectively. In comparison to the CT, the differences between 3D scan and CT in the male model volumes were 30.35 ± 2.70 cm3 (mean ± standard deviation) for WM and 11.60 ± 2.07 cm3 for MM. In the female model, the differences were 18.92 ± 2.66 cm3 and 11.18 ± 2.35 cm3, respectively. In both models, MM was significantly more accurate than WM (p < 0.001). When used in a clinical case, the scanner recorded changes in actual volume through the course of treatment. This cost-effective handheld 3D camera can be a reliable tool for evaluating hand edema even in cases of acute injury.

Blue Laser Irradiation Decreases the ATP Level in Mouse Skin and Increases the Production of Superoxide Anion and Hypochlorous Acid in Mouse Fibroblasts.

Photobiomodulation studies have reported that blue light irradiation induces the production of reactive oxygen species. We investigated the effect of blue laser (405 nm) irradiation on the ATP levels in mouse skin and determined the types of reactive oxygen species and reactive nitrogen species using cultured mouse fibroblasts. Blue laser irradiation caused a decrease in the ATP level in the mouse skin and triggered the generation of superoxide anion and hypochlorous acid, whereas nitric oxide and peroxynitrite were not detected. Moreover, blue laser irradiation resulted in reduced cell viability. It is believed that the decrease in the skin ATP level due to blue light irradiation results from the increased levels of oxidative stress due to the generation of reactive oxygen species. This method of systematically measuring the levels of reactive oxygen species and reactive nitrogen species may be useful for understanding the effects of irradiation conditions.

The Membrane-Like Structure From Extensor Tendon to the Nail in the Distal End of Digits: An Anatomical Study of Structure, Function, and Utility.

METHODS: The nail structures of 6 cadavers were investigated in each of the 10 digits of the hand. In the histological study, the thickness, length, and location of the SEP were measured in each digit of 3 cadavers. In the other 3 cadavers, the moving distance of the SEP was measured macroscopically with the distal interphalangeal joint in flexion at 0 to 60 degrees for confirmation of the function. This moving distance could be considered as an indicator of the SEP straining the surrounding (retaining) structure and improving the stability of the nail in pinches. RESULT: The SEP was recognized in all the digits. The average length of the SEPs was 2.38 ± 0.11 mm (mean ± SE). The average thickness of the SEPs was 0.35 ± 0.02 mm. The nail matrix and its feeding artery were found beneath the SEP in all digits. The average moving distance of the SEP was 1.38 ± 0.06 mm. This moving distance could be considered sufficiently large to support the role of SEP in the pinches compared with the excursion of the extensor tendon at the DIP joint in a previous report. CONCLUSIONS: The SEP has been shown to play an essential role in fingertip stabilization in pinches. It can serve as an anatomical marker to avoid iatrogenic damage to the nail matrix in surgical approaches.

First dorsal metacarpal artery perforator-based propeller flap: functional anatomy and clinical application in soft-tissue defects of the dorsal hand and digits.

BACKGROUND: Many approaches have been reported to repair soft-tissue defects of the hand using dorsal metacarpal artery flaps. Use of a perforator-based propeller flap from the first intermetacarpal space to the dorsum of the hand has been described. The aim of this study was to confirm the functional anatomy of a first dorsal metacarpal artery (FDMA) perforator flap. METHODS: Twenty-nine fixed cadaveric hands were dissected to determine the origin, course, and branches of the FDMA. Clinically, five cases of soft tissue defects of the hand underwent reconstructive surgery using an FDMA perforator-based propeller flap. RESULTS: The FDMA was found in 27 specimens (93%). The ulnar branch of the FDMA always supplied the cutaneous perforator (mean ± SD, 4.3 ± 1.6), and the most distal cutaneous perforating branch was found along the metacarpal long axis within 25 mm of the tip of the metacarpal head with high frequency (28/29, 97%). In the two hands that had aplasia of the FDMA, well-developed perforators arose directly from the radial artery and advanced to the metacarpal head. Seven hands (24%) had perforators arising from the palmar arterial system, penetrating through or passing close by the second metacarpal bone. In clinical application, all the flaps survived completely without major complications. CONCLUSIONS: The FDMA perforator-based propeller flap is minimally invasive and technically simple. It is expected to be a new option for hand reconstruction.

Angiogenic efficacy of ASC spheroids filtrated on porous nanosheets for the treatment of a diabetic skin ulcer.

Stem cell transplantation is expected to be an effective treatment for intractable skin ulcers by promoting angiogenesis; however, it is challenging to quickly realize a sufficient bloodstream for the ulcers. For this treatment, sheet-like materials with monolayer cells such as cell sheets have been investigated. However, they have a limitation of cell number that can be transplanted at one time due to the two-dimensional, monolayer cell structure, and sufficient secretion of growth factors cannot be expected. In this regard, cellular aggregates, such as spheroids, can reproduce three-dimensional cell-cell interactions that cause biological functions of living tissues more representative than monolayer cells, which is important to achieving efficient secretion of growth factors. In this study, we focused on free-standing porous polymer ultrathin films ("porous nanosheets") comprising poly(d,l-lactic acid) (PDLLA) and succeeded in developing a spheroid-covered nanosheet, on which more than 1000 spheroids from adipose-tissue derived stem cells (ASCs) were loaded. The porous structure with an average pore diameter of 4 µm allowed for facile filtration and carrying spheroids on the nanosheet, as well as sufficient oxygen and nutrients inflow to the cells. The spheroid-covered nanosheet achieved homogeneous transference of spheroids to a whole skin defect in diabetic model mice. Given the continuous release of vascular endothelial growth factor (VEGF) from the spheroids, the transplanted spheroids promoted healing with more accelerated angiogenesis than a nanosheet with a monolayer of cells. The spheroid-covered nanosheet may be a new regenerative material for promoting intractable skin ulcer healing.

Enhanced cellular engraftment of adipose-derived mesenchymal stem cell spheroids by using nanosheets as scaffolds.

The short survival time of transplanted adipose-derived mesenchymal stem cells (ASCs) is a problem for skin wound healing. Transplantation after the formation of cellular spheroids has been investigated as a promising method for prolonging cellular survival. However, there have been technical restrictions for transplantation of spheroids in clinical practice. Here, we show an effective method for transplantation of ASC spheroids onto skin wounds in order to efficiently cure refractory ulcers. To assist anchoring of spheroids onto skin wounds, we used a 120-nm-thick free-standing film (nanosheet) that has a highly adhesive property. Bioluminescence imaging showed that ASC spheroids carried by the nanosheet survived for 14 days, which is about two-times longer than that previously reported. Wounds treated with a nanosheet carrying ASC spheroids were 4-times smaller than untreated wounds on day 14. This method for transplantation of spheroids could be applied to cell therapy for various refractory skin wounds.

Triangular extension of hinge flaps: A novel technique to resolve stomal stenosis and prevent restenosis in staged buccal mucosal urethroplasty.

OBJECTIVES: To verify the utility of triangular extension of a hinge flap in buccal mucosal staged urethroplasty to resolve stomal stenosis after the first stage and ultimately prevent restenosis. METHODS: A total of 23 patients (triangular extension group) were studied in 2013-2019. In the first stage, buccal mucosa was transplanted, and an extended triangle portion of the mucosa was placed beside the proximal and/or distal stoma that was created when the stricture segment of the urethra was resected. In the second stage, during tubularization of the urethral plate, an incision was made at the stoma to increase the caliber to which the triangular extension was inserted. The procedure was considered successful when a 17-Fr flexible cystoscope passed through the reconstructed urethra at 6 months after the second-stage urethroplasty and no additional surgery or bougie dilation required. The clinical course of the triangular extension group was compared with 24 patients who underwent conventional staged urethroplasty (control group). RESULTS: In total, 20 patients from each group underwent second-stage surgery. No patients in the triangular extension group required additional revision surgery because of stomal stenosis after first-stage surgery, whereas five (20%) control patients did. Urethroplasty was successful in 19 patients (95%) in the triangular extension group and in 19 patients (95%) in the control group. Uroflowmetry after the second-stage surgery indicated that the mean maximum urinary flow rate was 21.5 and 15.8 mL/s after triangular extension and the control procedure, respectively (P = 0.027). CONCLUSIONS: The triangular extension technique reduces the need for revision surgery and prevents postoperative restenosis.

Aesthetic Consideration in a Patient With Lipomatosis.

ABSTRACT: This is the first report of multiple parosteal lipomas as a late complication of aesthetic procedures. A 70-year-old woman presented with multiple frontal nodules that had grown slowly over 5 years. She underwent forehead-lifting surgery 30 years ago and botulinum toxin injection 3 years ago. Computed tomography showed six low-density nodules measuring 10 to 20 mm just above the frontal bone. The tumors were resected via a parietal coronal incision. Histopathological findings revealed parosteal lipoma with foreign bodies. At 1 year postoperatively, there has been no recurrence or complications. The multiple lesions corresponded to the sites of the aesthetic procedures. The mesenchymal cells in the periosteum seemed to be stimulated by cytokines released from a postoperative hematoma or damaged periosteum, resulting in tumorigenesis. When performing aesthetic procedures in the face, care should be taken to avoid unnecessary injury to the periosteum, given the possibility of tumor development.Level of evidence: Level V, case report.

A banner flap with adjacent rotation flap for closure of circular skin defects: a schematic comparison with conventional rotation flap technique.

The local flap method is a minimally invasive, quick, and common technique of closing skin defects. Several methods using multiple local flaps are employed for the purpose of closing relatively large defects, and minimizing the resultant scar and deformity. We present a combined local flap method using a banner flap with an adjacent rotation flap (B-R flap) with the potential for closing circular defects. A retrospective analysis was performed in 15 patients treated with the B-R flap for circular skin defects over a 2-year period. The sizes of the flap and the healthy skin excision area were evaluated using image analysis software, and were compared to a model of a conventional rotation flap that would be necessary to close the same defect. All flaps were successfully engrafted. The B-R flap required a 39.1% smaller rotation flap and an 85.9% smaller area of healthy skin compared to the conventional rotation flap technique. There was one adverse event, partial epidermal necrosis that was conservatively treated and healed. The B-R flap is comparatively less invasive; it allows a smaller area of healthy skin to be excised. It can be a useful option for closing a circular defect.

Visualization of microstructural change affected by mechanical stimulation in tendon healing with a novel tensionless model.

Since the majority of a tendon's dry weight is collagen fibers, tendon healing consists mainly of collagen repair and observing three-dimensional networks of collagen fibers with scanning electron microscopy (SEM) is optimal for investigating this process. In this report, a cell-maceration/SEM method was used to investigate extrasynovial tendon (unwrapped tendon in synovial tissue such as the tendon sheath) healing of an injured Achilles tendon in a rat model. In addition, since mechanical stimulation is important for tendon healing, a novel, tensionless, rat lower leg tendon injury model was established and verified by visualizing the structural change of collagen fibers under tensionless conditions by SEM. This new model was created by transplanting the leg of a rat with a tendon laceration to the back, removing mechanical stimulation. We then compared the process of tendon healing with and without tension using SEM. Under tension, collagen at the tendon stump shows axial alignment and repair that subsequently demarcates the paratenon (connective tissue on the surface of an extrasynovial tendon) border. In contrast, under tensionless conditions, the collagen remains randomly arranged. Our findings demonstrate that mechanical stimulation contributes to axial arrangement and reinforces the importance of tendon tension in wound healing.

Management of Infected Calcific Myonecrosis: A Report of 2 Cases.

Calcific myonecrosis (CM) is a rare condition in which a large calcified mass develops after trauma. Generally, CM occurs in a lower extremity, and there have been no reports of its occurrence in the upper arm. We report 2 cases of infected CM, including a rare case of CM occurrence in the arm and a typical case in the leg. Case 1: An 84-year-old woman presented with a draining sinus and a large calcified mass in the arm and axillary region. The mass involved the neurovascular bundle; thus, complete resection was impossible. We performed surgical debridement and postoperative negative-pressure wound therapy with instillation and dwell. Case 2: A 43-year-old man presented with a large calcified mass in the right leg and 2 draining sinuses. After surgical debridement, negative-pressure wound therapy was initiated. However, the wound became infected, and we performed additional debridement, followed by a split thickness skin grafting. The infection was controlled in both patients, although complete resection was not feasible. Complete resection is generally considered the optimum treatment for infected CM, but it is difficult to achieve in some patients. Negative-pressure wound therapy with instillation and dwell appears as a good option for postoperative management if complete resection of infected CM cannot be achieved.

Stepwise surgery with variable adjustments for severe blepharochalasis with multiple chemical sensitivity: a case report.

We report a 29-year-old man with blepharochalasis and multiple chemical sensitivity (MCS). Although standard blepharoplasty with aponeurotic fixation was performed, palpebral ptosis recurred after 3 months. Eyelid function and appearance improved after additional operations. A stepwise surgical approach is appropriate in patients with blepharochalasis and MCS.

A case of nodular fasciitis that was difficult to distinguish from sarcoma.

INTRODUCTION: Nodular fasciitis is a reactive proliferative lesion. It is often difficult to distinguish from sarcoma, such as malignant peripheral nerve sheath tumor (MPNST). Therefore, both pathological findings and clinical features must be considered. PRESENTATION OF CASE: A 75-year-old man presented with a 1 × 1 cm mass on his left forearm that had enlarged rapidly without specific symptoms. Magnetic resonance imaging revealed a mass adjacent to brachioradialis. The lesion showed iso-intensity to muscle on T1-weighted images and hyperintensity on T2-weighted images. We made a clinical diagnosis of nodular fasciitis. Under observation, the mass gradually decreased in size and disappeared after two months. Four years later, another lesion appeared at the same site. We performed total excisional biopsy and histopathological examination indicated low grade MPNST or recurrent nodular fasciitis. Since malignancy could not be excluded, wide resection was performed. At 4 years postoperatively, there has been no recurrence. DISCUSSION: In this patient, nodular fasciitis of the right forearm was diagnosed clinically and showed spontaneous regression. However, recurrence was noted after four years. While the clinical features suggested recurrent nodular fasciitis, pathological findings indicated the possibility of low grade MPNST. CONCLUSION: When it is difficult to determine whether a lesion such as nodular fasciitis is benign or malignant, the patient should be managed by considering the possibility of malignancy.

Severe Functional Loss of the Hand due to Necrotizing Fasciitis with Underlying Vasculitis Neuropathy.

A 72-year-old man presented with an erythematous, painful, swollen, and blistering left hand associated with a systemic fever. The patient was diagnosed with microscopic polyangiitis and was receiving steroid therapy from a year before the incident. Based on a clinical diagnosis of necrotizing fasciitis, emergency surgery was performed within 2 days after the onset. ß-Hemolytic Streptococcus group A was isolated from a culture of the blood and wound. Radical debridement and high-dose penicillin and clindamycin therapy successfully saved the patient's life and affected limb except for the second finger on his left hand, which was completely necrotic. However, the function of the left hand was seriously decreased and did not recover. The important point to note in this case was the preexisting vasculitis neuropathy due to microscopic polyangiitis. The severe postoperative dysfunction of the hand was considered to be due to ischemic neuropathy that was aggravated by compartmental syndrome and microvascular thrombosis. In conclusion, necrotizing fasciitis of an extremity with underlying vasculitis neuropathy can lead to a poor functional prognosis of the limb.

Protective Effect of Extract of Ginkgo biloba 761 against Frostbite Injury in Rats.

BACKGROUND: When frostbite thaws, reperfusion injury has a crucial impact on tissue injury, and production of free radicals induces further tissue damage. This study examined whether extract of Ginkgo biloba 761 could ameliorate frostbite injury as a free radical scavenger. METHODS: Seventy-five Fisher 344 rats were divided into five groups of 15, and frostbite injury was created in each animal by sandwiching the left hind foot between a frozen magnet (-78.5°C) and a room-temperature magnet. Group I received saline; groups II, III, and IV received extract of Ginkgo biloba 761 (200, 100, and 50 mg/kg, respectively); and group V received superoxide dismutase (12 mg/kg). All drugs were injected intraperitoneally three times at 24-hour intervals. The wound surface area was measured throughout the wound healing period. Wounds were also harvested at various times to count cells stained by monoclonal antibodies for 4-hydroxy-2-nonenal and 8-hydroxy-2'-deoxyguanosine. RESULTS: Compared to group I, the wound surface area was significantly smaller in groups II and III on days 1 and 3 after wound creation. Histologic examination revealed significantly more 4-hydroxy-2-nonenal-stained cells and 8-hydroxy-2'-deoxyguanosine-stained cells in group I compared to other groups on day 1. However, there was no difference in the total healing period among the groups. A higher dose test of extract of Ginkgo biloba 761 (300 mg/kg daily) induced animal death, probably because of toxicity. CONCLUSION: Extract of Ginkgo biloba 761 demonstrated a protective effect against frostbite in the present model and probably alleviated reperfusion injury by reducing tissue peroxidation.

Radiation-induced thoracic necrosis with a pulmonary cutaneous fistula repaired using a free omental flap: a case report.

BACKGROUND: Chest wall necrosis can manifest as a late effect of radiation therapy for breast cancer. Only two cases of fistulas communicating with the respiratory tract as a result of radiation-induced necrosis of the lungs or bronchi have been reported. To the best of our knowledge, we report the first case of a pulmonary cutaneous fistula arising as a late effect of radiation therapy for breast cancer, which was successfully repaired using a free omental graft. CASE PRESENTATION: A 64-year-old woman underwent Halsted surgery and postoperative radiation therapy for breast cancer 25 years earlier. One year before visiting our hospital, she developed a fistula and bleeding in her left clavicular region, which was expanding. On initial examination, a 6-cm-wide skin defect was observed in the left clavicular region and the clavicle appeared sequestrated. Computed tomography revealed part of the first to third left ribs, part of the left clavicle, the subclavian artery, and the brachial plexus to be missing. Several rounds of debridement revealed approximately 10 bronchial stumps on the surface of the collapsed lung, from which exhaled air and sputum were effusing. Surgery was performed to implant a free omental flap with vascular anastomosis and a skin graft in the neck region, and the pulmonary cutaneous fistula was closed. Two years after surgery, emphysema remained inside the omentum, which spontaneously resolved by the 3rd postoperative year. CONCLUSIONS: Various treatment options are conceivable for the repair of pulmonary cutaneous and bronchocutaneous fistulas induced by radiation damage (e.g., free tissue grafts and endoscopic bronchial occlusion); however, these are rarely reported, and the most reliable method thus remains unclear. Positive outcomes in our case indicate that implanting a free omental graft may be effective. Furthermore, spontaneous healing can be expected for the residual emphysema inside the omentum.

In situ transplantation of adipose tissue-derived stem cells organized on porous polymer nanosheets for murine skin defects.

Stem cell transplantation is expected to be an effective early-phase treatment for deep burn injuries and intractable ulcers. Localizing and proliferating stem cells on the lesion utilizing engineered scaffolds is important for this treatment. In this study, we demonstrated in situ transplantation of adipose-tissue derived stem cells (ASCs) organized on free-standing porous polymer ultrathin films (referred to as "porous nanosheets") to a skin defect model in diabetic mice. Porous nanosheets were prepared by a combination of micro-gravure coating with macrophase separation of poly(d,l-lactic acid) and polystyrene under a roll-to-roll process and solvent etching process with cyclohexane. The permeable structure of porous nanosheets (thickness of 150 nm, average pore diameter of 4 µm) allowed for proliferation of ASCs and also provided sufficient nutrient inflow into multilayered ASC constructs. Then, transplantation of a trilayered ASC-laden porous nanosheet achieved homogeneous transference of ASCs onto the skin lesion. Transplanted ASCs contributed to wound healing in a dorsal skin defect model in diabetic mice. Thus, cell transplantation using porous nanosheets will be a new method for promoting wound healing in diabetic and other kinds of refractory ulcers. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1363-1371, 2019.

Approaches for Excision of Intramasseteric Nodules.

Developmental lesions, including benign or malignant tumors, rarely arise in the masseteric region. This retrospective study was performed to evaluate the adequacy of different surgical approaches in a series of patients with lesions in the masseteric region. The surgical methods, postoperative complications, pathological diagnosis, and aesthetic outcome were compared in 4 patients who underwent excision of intramasseteric mass lesions. A flap was elevated in 3 patients and direct incisional resection was performed in 1 patient. Two patients underwent incisional biopsy to exclude malignancy before the total excision was performed. The final diagnosis was hemangioma in 3 patients and schwannoma in 1 patient. All patients were satisfied with the aesthetic results and there were no major complications. In conclusion, surgery with skin flap elevation was concluded to be the best approach based on overall assessment of technical considerations, complications, and the cosmetic outcome. However, the surgeon should not hesitate to perform direct incisional biopsy when malignancy needs to be excluded.

FGF-2-containing dalteparin/protamine nanoparticles (FGF-2&D/P NPs) ameliorate UV-induced skin photoaging in hairless mice.

UVB exposure penetrates deeply into the dermis to alter skin barrier function, which is a primary factor in skin photoaging. We previously reported that dalteparin and protamine nanoparticles (D/P NPs) are effective carriers of FGF-2. This study aimed to examine the ability of FGF-2-containing D/P NPs (FGF-2&D/P NPs) to ameliorate UVB-induced skin photoaging in hairless mice. Dorsal skin of HR-1 hairless mice were exposed to UVB irradiation 5 days/week for 8 weeks (UV (+): final total, 2700 mJ/cm2). Mice were divided into four groups: Non-UVB (UV (-)) + saline, UV (+) + saline, UV (+) + FGF-2&D/P NPs, UV (+) + FGF-2, and UV (+) + D/P NPs, and following UVB irradiation, FGF-2&D/P NPs, FGF-2, and D/P NPs were applied to the groups of mice just after each UVB irradiation. Each group was subjected to evaluation of skin changes (elasticity), and histological examination using hematoxylin & eosin and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining. UVB irradiation of mice significantly induced a decline in elasticity and acanthosis, which was alleviated by application of FGF-2&D/P NPs. Furthermore, TUNEL-staining showed the proportions of apoptotic dermal fibroblast cells (DFCs) and epidermal keratinocyte cells (EKCs) in the UV (+) + FGF-2&D/P NPs group were significantly lower than those in the UV (+) + saline, UV (+) + FGF-2, and UV (+) + D/P NPs groups. Thus, FGF-2&D/P NPs may be effective in preventing skin photoaging accelerated by UVB irradiation such as declining elasticity, acanthosis, and apoptosis of DFCs and EKCs.