A New Ex Vivo Human Skin Burn Model.

Currently, most burn models for preclinical testing are on animals. For obvious ethical, anatomical, and physiological reasons, these models could be replaced with optimized ex vivo systems. The creation of a burn model on human skin using a pulsed dye laser could represent a relevant model for preclinical research. Six samples of excess human abdominal skin were obtained within one hour after surgery. Burn injuries were induced on small samples of cleaned skin using a pulsed dye laser on skin samples, at varying fluences, pulse numbers and illumination duration. In total, 70 burn injuries were performed on skin ex vivo before being histologically and dermato-pathologically analyzed. Irradiated burned skin samples were classified with a specified code representing burn degrees. Then, a selection of samples was inspected after 14 and 21 days to assess their capacity to heal spontaneously and re-epithelize. We determined the parameters of a pulsed dye laser inducing first, second, and third degree burns on human skin and with fixed parameters, especially superficial and deep second degree burns. After 21 days with the ex vivo model, neo-epidermis was formed. Our results showed that this simple, rapid, user-independent process creates reproducible and uniform burns of different, predictable degrees that are close to clinical reality. Human skin ex vivo models can be an alternative to and complete animal experimentation, particularly for preclinical large screening. This model could be used to foster the testing of new treatments on standardized degrees of burn injuries and thus improve therapeutic strategies.

Abdominal-based adipocutaneous advancement flap for reconstructing inguinal defects with contraindications to standard reconstructive approaches: a simple and safe salvage reconstructive option.

BACKGROUND: Groin wounds occurring after vascular surgical site infection, oncologic resection, or occasionally orthopedic surgery and trauma may represent a surgical challenge. Reconstruction of these defects by the usual workhorse flaps may be contraindicated following previous surgery and in patients with lower limb lymphedema or extreme morbidity. METHODS: This study included 15 consecutive patients presenting with inguinal wounds after vascular or general surgery that required debridement and soft tissue coverage. All cases had absolute or relative contraindications to conventional reconstructive techniques, including a compromised deep femoral artery network, limb lymphedema, scarring of potential flap harvesting sites, or poor overall condition. Abdominal adipocutaneous excess enabled the performance of adipocutaneous advancement flaps in an abdominoplasty-like fashion. Immediate and long-term outcomes were analyzed. RESULTS: Soft tissue coverage was effective in all cases. Two patients required re-intervention due to flap-related complications (venous congestion and partial flap necrosis). All patients fully recovered over a mean±standard deviation follow-up of 2.4±1.5 years. CONCLUSIONS: Abdominal flaps can be an effective and simple alternative technique for inguinal coverage with reproducible outcomes. In our experience, the main indications are a compromised deep femoral artery network and poor thigh tissue quality. Relative contraindications, such as previous open abdominal surgery, should be considered.

Evaluation of long-term breast shape in inferior versus superomedial pedicle reduction mammoplasty: a comparative study.

BACKGROUND: Among breast reduction mammoplasty, the inferior pedicle-based (IFP) technique is considered the most performed by plastic surgeons. A growing interest for the supero-medial based pedicle (SMP) mammoplasty technique has been documented in literature and clinical practice. However, no real evidence exists on the superiority of one technique over another. METHODS: This study represents a retrospective multimodal analysis, using a prospectively maintained database, comparing wise pattern breast reduction techniques (IFP vs. SMP) over a 24-month follow-up. From January 2015 to July 2017, all patients undergoing wise pattern bilateral reduction mammoplasty, using either an IFP or a SMP technique, were included in the study and divided in two groups. Pre-operative breast measurements included sternal notch-to-nipple distance (SN-N), infra-mammary fold to inferior border of Nipple Areolar Complex (NAC) distance length and ptosis. The same measurements were recorded at 2 weeks, 6 months and 24 months post-op. Complications were recorded and aesthetic outcomes were evaluated. RESULTS: A total of 58 patients were included in the study, among which 36 (62%) were treated with a SMP technique and 22 (38%) with an IFP technique. At the 24-month follow-up timepoint, the SN-N distance was significantly shorter (*P<0.05) in the SMP group, with a significantly smaller elongation of the lower pole arc (29.5% increase in length in the SMP group and 40.9% in the IFP group). Aesthetic result gave significantly higher mean VAS score for SMP patients compared to IFP patients. CONCLUSIONS: The SMP technique provides stable and satisfactory results in term of breast shape, overcoming some of the major concerns related to the use of an IFP technique (lower pole elongation and ptosis recurrence), maintaining a superimposable complication rate.

Trace element intakes should be revisited in burn nutrition protocols: A cohort study.

BACKGROUND & AIMS: Due to inflammatory and hypermetabolic responses and to extensive exudative trace element (TEs) losses, major burn patients have substantially increased nutritional requirements. To date, information is only available for Cu, Se, and Zn. We aimed at analyzing losses of 12 TEs and Mg through burn wound exudation and corresponding plasma concentrations during the first week after burn injury, and to evaluate the impact of current TE repletion protocols. METHODS: Burn wound exudate was collected under negative pressure in 15 adult patients burned 29 ± 20% of body surface (TBSA) for 8 days after injury. Two samples were collected daily. The TE concentrations were measured by inductively coupled plasma mass spectrometry (ICP-MS). Losses and serum concentrations were compared to intakes. RESULTS: For the majority of 12 TEs, the highest losses were observed on day 1, and declined thereafter. Despite Cu supplementation (4.23 mg/day) serum levels remained below reference values. Se supplements (745 µg/day) normalized and even increased serum levels to upper normal value. Despite large supplements (Zn 67.5 mg/day), serum Zn values remained below reference range. Large exudative losses of B, Br and Mg were found, as well as of Fe and I, with the latter being probably due to contamination. CONCLUSION: Current nutritional Cu, Se, Zn repletion protocols in major burn patients which were based on measured exudative losses should be revised to include higher Cu and lower Se doses, as well as planned Mg administration. In burns <20% TBSA and for the other TEs the recommended parenteral nutrition TE doses appear sufficient.

Regeneration patterns influence hindlimb automutilation after sciatic nerve repair using stem cells in rats.

INTRODUCTION: Hindlimb autophagy is common after rat sciatic total axotomy and is considered as a sign of neuropathic pain. We applied adult stem cells in a fibrin conduit in a total sciatic axotomy model to improve nerve regeneration, investigating whether a correlation could be detected between stem cells effects on regeneration and limb autophagy. MATERIAL AND METHODS: After sciatic nerve section, a 1-cm sciatic gap was crossed using fibrin conduits. Experimental groups included empty fibrin conduits, fibrin conduits seeded with primary Schwann cells, and fibrin conduits seeded with Schwann cell-like differentiated mesenchymal or adipose-derived stem cells (dMSCs and dASCs). Controls were represented by autografts and by sham rats (tot n=34). At 16 weeks post-implantation, regeneration pattern was analysed on histological sections and related to eventual autophagy. Hindlimbs were evaluated and scored according to autophagy Wall's scale and X-Rays radiological evaluation. RESULTS: All regenerative cell lines significantly improved myelination at the mid conduit level, compared to the empty tubes. However, dMSC could not significantly improve myelination at the distal stump, showing a more chaotic regeneration compared to both other cells groups and controls. Autophagy was correlated to this regeneration patterns, with higher autophagy scores in the empty and dMSC group. CONCLUSION: Hindlimb autophagy can be used as index of neuropathic pain due to nerve lesion or on-going immature regeneration. dMSC group was characterized by a less targeted regeneration comparing to dASC and primary Schwann cells, which confirmed their effectiveness in regeneration and potential in future clinical applications.

Determinants of neurological functional recovery potential after stroke in young adults.

BACKGROUND/OBJECTIVES: Despite recent progress in stroke prevention and acute treatment, neurorehabilitation remains one of the main methods of treatment in the management of stroke patients. The aim of this study is to point out some important predicting factors of in-hospital neurorehabilitation outcomes. METHODS: A rehabilitation registry including all patients who had undergone a standardized program of neurorehabilitation at the neurorehabilitation unit of the Lausanne University Hospital, Lausanne, Switzerland, was created. Patients aged <65 years and having experienced a first ever nontraumatic stroke from 2005 to 2010 were admitted. Using logistical regression models, predicting factors for each patient were compared to the exit Functional Independence Measure (FIM) score. RESULTS: Age >55 years, gender, aphasia, hemilateral spatial neglect, spasticity, complications, length of stay >70 days, entry FIM >100 and relative possible FIM gain/week of >10% were considered to be significant and independent predicting factors of the neurorehabilitation outcome. DISCUSSION/CONCLUSION: Some factors of the in-hospital rehabilitation period have been identified before (spasticity, complications, length of stay, relative possible FIM gain/week) and should be considered for a better management of the neurorehabilitation therapy. In addition, a personalized rehabilitation strategy based on the patient's individual needs should be aimed at. The question of resource allocation can also be addressed with regard to the present findings.

Ross procedure: is the root replacement technique superior to the sub-coronary implantation technique? Long-term results.

There is controversy over the use of the Ross procedure with regard to the sub-coronary and root replacement technique and its long-term durability. A systematic review of the literature may provide insight into the outcomes of these two surgical subvariants. A systematic review of reports between 1967 and February 2013 on sub-coronary and root replacement Ross procedures was undertaken. Twenty-four articles were included and divided into (i) sub-coronary technique and (ii) root replacement technique. The 10-year survival rate for a mixed-patient population in the sub-coronary procedure was 87.3% with a 95% confidence interval (CI) of 79.7-93.4 and 89.1% (95% CI, 85.3-92.1) in the root replacement technique category. For adults, it was 94 vs 95.3% (CI, 88.9-98.1) and in the paediatric series it was 90 vs 92.7% (CI, 86.9-96.0), respectively. Freedom from reoperation at 10 years was, in the mixed population, 83.3% (95% CI, 69.9-93.4) and 93.3% (95% CI, 89.4-95.9) for sub-coronary versus root replacement technique, respectively. In adults, it was 98 vs 91.2% (95% CI, 82.4-295.8), and in the paediatric series 93.3 vs 92.0% (95% CI, 86.1-96.5) for sub-coronary versus root replacement technique, respectively. The Ross procedure arguably has satisfactory results over 5 and 10 years for both adults and children. The results do not support the advantages of the sub-coronary technique over the root replacement technique. Root replacement was of benefit to patients undergoing reoperations on neoaorta and for long-term survival in mixed series.