Adaptive patterning of vascular network during avian skin development: Mesenchymal plasticity and dermal vasculogenesis.

A vasculature network supplies blood to feather buds in the developing skin. Does the vasculature network during early skin development form by sequential sprouting from the central vasculature or does local vasculogenesis occur first that then connect with the central vascular tree? Using transgenic Japanese quail Tg(TIE1p.H2B-eYFP), we observe that vascular progenitor cells appear after feather primordia formation. The vasculature then radiates out from each bud and connects with primordial vessels from neighboring buds. Later they connect with the central vasculature. Epithelial-mesenchymal recombination shows local vasculature is patterned by the epithelium, which expresses FGF2 and VEGF. Perturbing noggin expression leads to abnormal vascularization. To study endothelial origin, we compare transcriptomes of TIE1p.H2B-eYFP+ cells collected from the skin and aorta. Endothelial cells from the skin more closely resemble skin dermal cells than those from the aorta. The results show developing chicken skin vasculature is assembled by (1) physiological vasculogenesis from the peripheral tissue, and (2) subsequently connects with the central vasculature. The work implies mesenchymal plasticity and convergent differentiation play significant roles in development, and such processes may be re-activated during adult regeneration. SUMMARY STATEMENT: We show the vasculature network in the chicken skin is assembled using existing feather buds as the template, and endothelia are derived from local bud dermis and central vasculature.

Positive Association Between Fluoroquinolone Exposure and Tendon Disorders: A Nationwide Population-Based Cohort Study in Taiwan.

Introduction: Fluoroquinolone exposure is reportedly associated with a higher risk of tendon disorders, tendonitis, or tendon rupture. However, studies in East Asian populations have not confirmed these risks in patients with comorbidities or concomitant medication use. This cohort study was designed to investigate the associations among fluoroquinolone exposure, comorbidities, medication use, and tendon disorders in Taiwan. Materials and Methods: This population-based, nationwide, observational, cohort study used data from the National Health Insurance Research database in Taiwan, a nationwide claims database that covers more than 99% of the Taiwanese population. The study period was from January 2000 to December 2015, and the median follow-up time was 11.05 ± 10.91 years. Patients who were exposed to fluoroquinolones for more than three consecutive days were enrolled, and patients without fluoroquinolone exposure who were matched by age, sex, and index year were enrolled as controls. The associations of comorbidities and concomitant medication use with tendon disorder occurrence were analyzed using Cox regression models. Results: The incidence of tendon disorders were 6.61 and 3.34 per 105 person-years in patients with and without fluoroquinolone exposure, respectively (adjusted hazard ratio, 1.423; 95% confidence interval [1.02,1.87]; p = 0.021). Sensitivity analyses yielded similar results. Patients under 18 and over 60 years with fluoroquinolone exposure; those with chronic kidney disease, diabetes, rheumatologic disease, cardiac disease, lipid disorder, or obesity; and those who concomitantly used statins, aromatase inhibitors, or glucocorticoids, had a significantly higher risk of tendon disorders. Conclusion: The long-term risk of tendon disorders was higher in patients with fluoroquinolone exposure than in those without fluoroquinolone exposure. Clinicians should assess the benefits and risks of fluoroquinolone use in patients at high risk of tendon disorders who require fluoroquinolone administration.

Severe burn injury from the common Asian practice of heat application in patients with diabetic neuropathy.

This was the first study to analyse patients who sustained severe self-induced burns from this common Asian practice. There is a need to raise public awareness and physician attention about the consequences of preventable burn injuries and the importance of first aid in patients with diabetic neuropathy. Retrospective data on 16 consecutive patients who had diabetes and neuropathy admitted to the plastic surgery ward at the Tri-Service General Hospital from January 1, 2015, to February 2, 2021 with burn injuries because of heat applications were collected and analysed for this study. Age, gender, season, first aid adequacy, comorbidity, interventions, total body surface area (TBSA), degree of burn, aetiology, length of stay (LOS), and status at discharge were reviewed. The mean age of the 16 patients was 65.13 years. The most common burn aetiology was contact (50%), followed by scald (37.5%) and radiation burns (12.5%). TBSA burn averaged ± standard deviation 1.54 ± 1.22. Seven patients (44%) had wound infections, and three patients underwent amputations. The average LOS was 28.2 days. Asian practice of heat application is the common aetiology of severe and preventable burn injuries. Education about neuropathy and the consequences of a burn injury should be provided to patients with diabetes.

Risk factors that predict major amputations and amputation time intervals for hospitalised diabetic patients with foot complications.

Diabetes-related lower extremity amputations are an enormous burden on global health care and social resources because of the rapid worldwide growth of the diabetic population. This research aimed to determine risk factors that predict major amputation and analyse the time interval from first hospitalisation to amputation by using standard management protocols and Kaplan-Meier survival curves. Data from 246 patients with diabetes mellitus and diabetic foot ulcers from the Division of Plastic and Reconstructive Surgery of the Department of Surgery at XXX Hospital between January 2016 and May 2020 were analysed. Univariate and multivariate analyses of 44 potential risk factors, including invasive ulcer depth and C-reactive protein levels, showed statistically significant differences for those at increased risk for major amputation. The median time from hospitalisation to lower extremity amputation was approximately 35 days. Most patients with abnormal C-reactive protein levels and approximately 70% of patients with ulcers invading the bone were at risk for lower extremity amputations within 35 days. Therefore, invasive ulcer depth and C-reactive protein levels are significant risk factors. Other potential risk factors for major amputation and the time intervals from first hospitalisation to amputation should be analysed to establish further prediction strategies.

The Optimal Application of Medium Potency Topical Corticosteroids in Preventing Laser-Induced Inflammatory Responses-An Animal Study.

BACKGROUND: During ablative fractional resurfacing (AFR) laser therapy, thermal damage to the skin is inevitable, resulting in inflammatory responses and small wounds. Corticosteroids are known for their anti-inflammatory effect. However, inappropriate application of corticosteroids carries the risk of delayed wound healing. Therefore, we aimed to find the optimal administration route, timing, and duration of medium potency corticosteroid treatment to prevent AFR laser-induced inflammatory responses and to minimize the risk of delayed wound healing. METHODS: We determined the anti-inflammatory efficacy of corticosteroids by skin erythema and tissue biopsies on C57BL/6 mice. Wound healing was evaluated by crust area and epithelial gap. Finally, Masson's trichrome stain and α-SMA immunohistochemistry stain were used to analyze scar contracture. RESULTS: Our results demonstrated that one dose of medium-potency topical corticosteroid applied immediately after AFR laser treatment could prevent erythema effectively with minimal disruption to wound healing. Notably, when more than one dose was administered, wound healing was delayed and scar contracture was aggravated by the application of medium-potency topical corticosteroids in a dosage-dependent manner. CONCLUSION: Our findings suggested that single-dose medium-potency topical corticosteroids could potentially improve AFR laser-induced acute inflammatory responses in clinical applications.

Negative Pressure Wound Therapy in Conjunction With Artificial Dermis for Burned Hand Reconstruction.

INTRODUCTION: Proper wound care along with the use of skin grafts over deep burn wounds has been the standard treatment. However, the goal in burn wound care has shifted from achieving a satisfactory survival rate to improving long-term form and function of the healed wound, which is sometimes hindered by scar contracture. This has prompted surgeons to find alternative ways to treat burn wounds without compromising function. Among burn cases, hand injuries are the most problematic when it comes to delicate function recovery. METHODS: This study presents the results of conjunctive use of a bilayer artificial dermis, negative pressure wound therapy, and split-thickness skin grafts for grafting over acute burn wounds and scar-releasing defects after severe hand burns. RESULTS: Three months after the operation, the scar was soft and pliable, the aesthetic outcome was good, and the patients gained much improvement in hand function and quality oflife. CONCLUSIONS: The combined technique achieved a good scar quality and aesthetic effect on burned hands as well as excellent functional outcome, which resulted in major improvements and an independent life for the patient.

Clinical Performance of Hydrogel-based Dressing in Facial Burn Wounds: A Retrospective Observational Study.

ABSTRACT: Preserving both esthetic and functional outcome remains challenging in facial burn injuries. The major issue is the initial treatment of injury. In this study, we focused on patients with partial-thickness facial burns admitted to the burn unit of Tri-Service General Hospital, Taipei, from November 2016 to November 2018. In 21 included patients, customized mask-style, transparent hydrogel-based dressing was applied to the burns. The mean age of included patients was 37.4 years. The mean area of burn injury was 11.9% of total body surface area, and the mean area of second-degree facial burns was 162.3 cm2. Full reepithelialization took, on average, 10.86 days. Scarring was acceptable in terms of texture and color, and no hypertrophic or keloidal scarring was noted. The mean Vancouver Scar Scale score was 2.07. Use of the hydrogel-based dressing masks seems to be a promising means of reducing pain, providing uninterrupted wound healing, facilitating observation, and positively affecting scarring in patients with second-degree facial burns.

Surgical treatment and strategy in patients with pressure sores: A single-surgeon experience.

With aging, pressure ulcers become a common health problem causing significant morbidity and mortality for physically limited or bedridden elderly persons. Here, we present our strategy for such patients. Between August 2010 and March 2019, 117 patients were enrolled. Patient age, etiology, defect size and location, flap reconstruction, outcome, and follow-up period were reviewed. Of these patients, 64 were female and 53 were male, with an age range of 21 to 96 years (mean 75.6). The mean area of defect was 61.5 cm. The most common etiology was dementia (33.3%), and ulcers were most frequently caused by sacral pressure (70.3%). The commonest surgical treatment was a V-Y advancement flap (50%). The complication rate was 27.5%, including dehiscence and late recurrence. Negative pressure wound therapy could be used if the initial defect was large. V-Y advancement flap is the most frequent surgical treatment for sacral pressure ulcers because it is simple and available for most types of defect. Primary closure may be considered as the simplest method if the defective area is <16 cm. Intraoperative indocyanine green angiography can help avoid secondary flap revisions. Our protocol ensures a short surgery time, little bleeding, and a low complication rate.

Comparative regenerative biology of spiny (Acomys cahirinus) and laboratory (Mus musculus) mouse skin.

Wound-induced hair follicle neogenesis (WIHN) has been demonstrated in laboratory mice (Mus musculus) after large (>1.5 × 1.5 cm2 ) full-thickness wounds. WIHN occurs more robustly in African spiny mice (Acomys cahirinus), which undergo autotomy to escape predation. Yet, the non-WIHN regenerative ability of the spiny mouse skin has not been explored. To understand the regenerative ability of the spiny mouse, we characterized skin features such as hair types, hair cycling, and the response to small and large wounds. We found that spiny mouse skin contains a large portion of adipose tissue. The spiny mouse hair bulge is larger and shows high expression of stem cell markers, K15 and CD34. All hair types cycle synchronously. To our surprise, the hair cycle is longer and less frequent than in laboratory mice. Newborn hair follicles in anagen are more mature than C57Bl/6 and demonstrate molecular features similar to C57Bl/6 adult hairs. The second hair cycling wave begins at week 4 and lasts for 5 weeks, then telogen lasts for 30 weeks. The third wave has a 6-week anagen, and even longer telogen. After plucking, spiny mouse hairs regenerate in about 5 days, similar to that of C57Bl/6. After large full-thickness excisional wounding, there is more de novo hair formation than C57Bl/6. Also, all hair types are present and pigmented, in contrast to the unpigmented zigzag hairs in C57Bl/6 WIHN. These findings shed new light on the regenerative biology of WIHN and may help us understand the control of skin repair vs regeneration.

Self-organizing hair peg-like structures from dissociated skin progenitor cells: New insights for human hair follicle organoid engineering and Turing patterning in an asymmetric morphogenetic field.

Human skin progenitor cells will form new hair follicles, although at a low efficiency, when injected into nude mouse skin. To better study and improve upon this regenerative process, we developed an in vitro system to analyse the morphogenetic cell behaviour in detail and modulate physical-chemical parameters to more effectively generate hair primordia. In this three-dimensional culture, dissociated human neonatal foreskin keratinocytes self-assembled into a planar epidermal layer while fetal scalp dermal cells coalesced into stripes, then large clusters, and finally small clusters resembling dermal condensations. At sites of dermal clustering, subjacent epidermal cells protruded to form hair peg-like structures, molecularly resembling hair pegs within the sequence of follicular development. The hair peg-like structures emerged in a coordinated, formative wave, moving from periphery to centre, suggesting that the droplet culture constitutes a microcosm with an asymmetric morphogenetic field. In vivo, hair follicle populations also form in a progressive wave, implying the summation of local periodic patterning events with an asymmetric global influence. To further understand this global patterning process, we developed a mathematical simulation using Turing activator-inhibitor principles in an asymmetric morphogenetic field. Together, our culture system provides a suitable platform to (a) analyse the self-assembly behaviour of hair progenitor cells into periodically arranged hair primordia and (b) identify parameters that impact the formation of hair primordia in an asymmetric morphogenetic field. This understanding will enhance our future ability to successfully engineer human hair follicle organoids.

Use of split-thickness plantar skin grafts in the management of leg and foot skin defects.

The basic principle of donor site selection is to take skin from areas that will heal with minimal scarring while balancing the needs of the recipient site. For skin loss from the lower legs and feet, the most common harvest site for split-thickness skin grafts is the anterior or posterior thigh; grafts from the plantar areas have been mostly used to cover the volar aspect of digits and palms. Between September 2015 and September 2017, 42 patients with areas of skin loss on the legs or feet were treated with plantar skin grafts because of their cosmetic benefits and the convenience of the surgical procedure and postoperative wound care. Our technique of harvesting a single layer of split-thickness skin graft (0.014 in. thick) from a non-weight-bearing area of the foot of the injured leg is simple and provided good functional and cosmetic outcomes at both the donor and recipient sites. All patients were very satisfied with the recovery progress and final results. Therefore, in the management of skin defects in the lower legs or feet that comprise less than 1.5% of the total body surface area, our surgical method is a reliable alternative to anterior or posterior thigh skin grafting.

Cranioplasty Using a Novel Osteoconductive Scaffold and Platelet Gel.

BACKGROUND: Commonly used materials for cranioplasty include autogenous bone grafts, methyl methacrylate, and titanium mesh. We evaluated a novel osteoconductive scaffold [N-isopropylacrylamide cross-linked with acrylic acid using γ-rays (ANa powder)] mixed with platelet gel for cranioplasty. METHODS: ANa powder mixed with platelet gel was implanted into a 15 × 15-mm, full-thickness calvarial bone defect in 5 New Zealand white rabbits. ANa powder mixed with phosphate-buffered saline was implanted in 5 rabbits. The calvarial bone defect was left unreconstructed in another 5 rabbits. Twelve weeks after surgery, computed tomography examination was used to evaluate the radiographic evidence of bone healing in vivo. Bone specimens were then retrieved for histologic study. RESULTS: The ANa scaffold mixed with platelet gel is biocompatible, biodegradable, and both osteoconductive and osteoinductive, leading to progressive growth of new bone into the calvarial bone defect. CONCLUSION: The use of this novel osteoconductive scaffold combined with osteoinductive platelet gel offers a valuable alternative for the reconstruction of calvarial bone defects.

Cerebellar and oculomotor dysfunction induced by rapid infusion of pethidine.

Pethidine is an opioid that gains its popularity for the effective pain control through acting on the opioid-receptors. However, rapid pain relief sometimes brings about unfavourable side effects that largely limit its clinical utility. Common side effects include nausea, vomiting and hypotension. In patients with impaired renal and liver function, and those who need long-term pain control, pethidine may cause excitatory central nervous system (CNS) effects through its neurotoxic metabolite, norpethidine, resulting in irritability and seizure attack. On the contrary, though not clinically apparent, pethidine potentially causes inhibitory impacts on the CNS and impairs normal cerebellar and oculomotor function in the short term. In this case report, we highlight opioid's inhibitory side effects on the cerebellar structure that causes dysmetria, dysarthria, reduced smooth pursuit gain and decreased saccadic velocity.

The lower trapezius musculocutaneous flap for head and neck reconstruction: two decades of clinical experience.

BACKGROUND: Microsurgical free flap has gained the popularity over pedicle flap nowadays in the reconstruction of head and neck. However, pedicled flaps remain a promising alternative and have a remarkable position in selected patients. This review study aimed to determine the reliability and versatility of the lower trapezius musculocutaneous flap for reconstructing complex defects in the head and neck. METHODS: Between 1993 and 2012, 22 male and 10 female patients underwent a total of 32 lower trapezius flap reconstructions for complex defects that included neoplasm extirpation (n = 21), radionecrosis (n = 6), dehisced laminectomy (n = 2), pressure sore (n = 2), and necrotizing fasciitis (n = 1). The most common site of defect was the perioral region, followed by the neck, posterior skull, back, temporal region, shoulder, and the upper arm. Flap design was based on the defect size and location, as well as the ability to close the donor site primarily and to preserve muscle function. Outcome has been evaluated by the hospital course, postoperative morbidity, mortality, resultant cosmetics, and function at donor and recipient sites. RESULTS: Stable wound coverage with total flap survival was achieved in 30 (93.75%) patients, 2 patients had partial flap necrosis which required flap reinsertion and skin graft coverage. All donor sites were closed primarily. Seroma developed in 2 (6.25%) patients, which were solved by needle aspiration. All muscle function was preserved. Eight patients died of their primary disease. CONCLUSIONS: For selected patients who have advanced stage cancer, surgical sequelae after free flap surgery, unable to tolerate microsurgery, or special defect location, pedicled lower trapezius musculocutaneous flap provides efficient and effective reconstruction for complex defects especially in the head and neck.

Three abdominal defects, three pedicled flaps.

The reconstruction of complex defects in the abdominal wall after wound infection or trauma can be challenging. In this article, a superficial inferior epigastric artery flap, a tensor fascia lata flap, and an anterolateral thigh flap used for 3 different abdominal wall reconstructions are described. The authors conclude that different specific abdominal wall defects can be successfully reconstructed using different pedicled flaps in simple and effective single-stage reconstructions.

Application of marionette technique for 3-port laparoscopic liver resection.

BACKGROUND: Laparoscopic liver resection has become a feasible and safe procedure for liver tumor, but it requires experienced surgeons in the case of hepatobiliary and laparoscopic surgeries. More minimally invasive laparoscopic techniques of liver surgery are developed. We here report our experience of using a marionette technique for 3-port laparoscopic liver resection. METHODS: Between June 2009 and December 2010, 7 patients underwent 3-port laparoscopic liver resection with the use of marionette technique. Five patients had hepatocellular carcinoma. Two patients with prior abdominal operations for colon cancer had colorectal liver metastasis. The procedure of marionette technique was performed as below: after insertion of the 3 trocars, a 2-0 nylon straight needle line was inserted through the abdominal wall, and using the needle holder, it was allowed to traverse the liver edge twice. Then, the straight needle line was forced out of the abdominal wall and clamped using mosquito for traction. Another straight needle line was similarly created at the opposite side of the liver edge. RESULTS: None of the patients had to be converted to open surgery. The mean operative time was 96.7 ± 63.2 minutes (range, 45 to 195 min), and the mean volume of blood loss was 45.6 ± 27.9 mL (range, 30 to 100 mL). The mean pain score recorded on the visual analog scale was 2.7 ± 0.8. The mean hospital stay was 5.6 ± 1.7 days (range, 4 to 9 d). Currently, all the 7 patients are alive, and the tumors have not recurred (Supplementary Digital Content video 1 http://links.lww.com/SLE/A67). CONCLUSIONS: Our experience demonstrated that the simple marionette technique procedure could help surgeons ease laparoscopic liver resection and achieve better postoperative results.

Resurfacing tophaceous gout in the foot with anterolateral thigh flap.

We report the case of a 46-year-old patient who suffered from huge tophus masses involving the metatarsal joints of the big toes of both feet, with infection and skin necrosis secondary to chronic tophaceous gout. After conventional curettage and debridement of each lesion, a free anterolateral thigh flap (ALTF) was used to resurface the circumferential wound, protect the underlying structures, and provide a gliding surface for the exposed tendons. The flap was safely raised and debulked during revision surgery, and excellent functional and cosmetic results were apparent at the 2-year follow-up. We consider ALTF to be a valuable option for the coverage of necrotic skin over tophi after adequate debridement.