High-Quality Lipoaspirate Following 1470-nm Radial Emitting Laser-Assisted Liposuction.

BACKGROUND: Laser-assisted liposuction (LAL) has been used to maximize viable adipocyte yields in lipoaspirates, although optimizing tissue processing methods is still a challenge. A high-quality lipoaspirate has been a key factor for extended graft longevity. OBJECTIVE: To assess the viability and potency of stromal vascular fraction (SVF) cells and adipose-derived stem cells (ASCs) in fat samples from lipoaspirates harvested with a novel 1470-nm diode, radial emitting LAL platform. Two processing methods, enzymatic and nonenzymatic, were compared. METHODS: Laser-assisted liposuction lipoaspirates harvested from 10 subjects were examined for cell viability after processing by enzymatic or nonenzymatic methods. Isolated SVF cells were cultured with an ASC-permissive medium to assess their viability and proliferation capacity by cell proliferation assay. Flow cytometric analysis with ASC-specific markers, gene expression levels, and immunofluorescence for ASC transcription factors were also conducted. RESULTS: Lipoaspirates showed high SVF cell viability of 97% ± 0.02% and 98% ± 0.01%, averaged SVF cell count of 8.7 × 10 6 ± 3.9 × 10 6 and 9.4 × 10 6 ± 4.2 × 10 6 cells per mL, and averaged ASC count of 1 × 10 6 ± 2.2 × 10 5 and 1.2 × 10 6 ± 5 × 10 5 cells per mL in nonenzymatic and enzymatic methods, respectively. The ASC-specific markers, gene expression levels, and immunofluorescence for ASC transcription factors confirmed the adipose origin of the cells. CONCLUSIONS: The laser lipoaspirates provide a high yield of viable and potent SVF cells and ASCs through both nonenzymatic and enzymatic processes. Improved purity of the harvested lipoaspirate and high ASC content are expected to result in extended graft longevity. Furthermore, eliminating enzymatic digestion may provide advantages, such as reducing process time, cost, and regulatory constraints.

Bromelain-based enzymatic debridement of chronic wounds: Results of a multicentre randomized controlled trial.

Chronic wounds are estimated to affect over 6 million people annually in the United States with an estimated annual cost of $25 billion. Debridement represents a key step in their management and is considered a basic necessity to induce the functional process of tissue repair. However, there is an unmet need for an efficient rapid acting non-surgical debridement agent. Bromelain-based enzymatic debridement has been proven to provide an effective, selective and safe non-surgical debridement in deep burns. EscharEx (MediWound Ltd, Yavne, Israel), is a bromelain-based enzymatic debridement agent currently in development for chronic wounds. The aim of this study was to assess its safety and efficacy in chronic wounds. Seventy-three patients suffering from a lower extremity ulcer of diabetic/venous insufficiency/post-surgical/traumatic aetiology were enrolled in a multicentre, assessor blinded, randomized controlled trial. Patients were randomized to topical treatment by either EscharEx or its gel vehicle for up to 10 daily 4 hour applications, and then continued follow-up for up to 6 months. The EscharEx arm achieved a significantly higher incidence of complete debridement compared to the gel vehicle arm; 55 versus 29% (p = .047), thus meeting the primary endpoint of this study. The EscharEx and gel vehicle arms achieved similar reductions in wound area, non-viable tissue area and wound healing scores during the debridement period. There were no significant differences between the arms in the incidence of complete wound closure (41% in the EsxcharEx arm vs. 53% in the gel vehicle arm) and in the mean time to complete wound closure (70.0 ± 32.8 days in the EsxcharEx arm vs. 65.7 ± 38.4 days in gel vehicle arm). There were no significant safety issues and EscharEx demonstrated a favourable benefit to risk profile.

Very high thermopower of Bi nanowires with embedded quantum point contacts.

Quantum confinement effects in bismuth (Bi) nanowires (NWs) are predicted to impart them with high thermopower values and hence make them efficient thermoelectric materials. Yet, boundary scattering of charge carriers in these NWs operating in the diffusion transport regime mask any quantum effects and impede their use for nanoscale thermoelectric applications. Here we demonstrate quantum confinement effects in Bi NWs by forming in their structure ballistic quantum point contacts (QPCs) leading to exceptionally high thermopower values (S > 2 mV/K). The power factor, S(2)G, of the QPCs is maximized at G ~ 0.25G(0) (where G(0) is the quantum of conductance) within agreement with a one-band model with step edge characteristics.

The efficacy of combined ultrasound and electric field stimulation therapy in the treatment of venous leg ulcers.

Introduction: Venous leg ulcers are the most common cause of leg ulcers. The aim of this study is to assess the effect of Combined Ultrasound and Electric Field Stimulation therapies (CUSEFS) on wound surface area and pain level in patients with venous leg ulcers, utilizing a novel device (BRH-A2 from BRH Medical, Ltd). Methods: This prospective case series study, conducted by the Department of Plastic Surgery at the Yitzhak Shamir Medical Center, Israel, collected data for subjects treated with CUSEFS with the BRH-A2 device, between April 2018 and September 2019. Measurements of wound area and assessment of pain intensity using a 10-point visual analog score were recorded. At the end of the four-week period, average wound area and pain scores were included for analysis. Results: Ten consecutive patients met the inclusion criteria. During the study period, all patients exhibited a reduction in the wound surface area. The final average wound surface area was reduced by 53.52% following the combined treatment. Eight out of the ten patients (80%) reported a reduction in pain, with an average pain level reduction of 64% throughout eight consecutive treatments. Conclusion: CUSEFS therapies with BRH-A2 technology is a promising treatment for venous leg ulcers. In accordance with our preliminary results, this treatment modality can aid in the reduction of wound surface area as well as reducing the pain suffered by patients from these chronic wounds. Larger multicenter studies are needed to further quantify and qualify the beneficial effect of CUSEFS in venous leg ulcers and other chronic wounds. Lay Summary: Venous leg ulcers (VLUs) are painful wounds occurring between the knee and ankle joint, that fail to heal for a period of at least two weeks and occur in the presence of venous disease. VLUs, are the most common cause of leg ulcers, affecting approximately 5% of the general population over the age of 65. Numerous non-invasive treatment modalities have been attempted for healing chronic wounds and ulceration, however, in some instances surgery, although invasive, is the preferred option. For many years, ultrasound (US) has been used therapeutically to treat chronic ulcers. US produces biophysical effects that are significantly beneficial to the wound healing process. Electrical stimulation therapy is another treatment option which contributes to wound healing by influencing the electrochemical wound process.Combined Modulated Ultrasound and Electric Field Stimulation (CUSEFS) have been shown to improve the healing of chronic wounds. However, research has focused predominantly on objective measures of healing, while less consideration has been given to researching the subjective discomfort and the negative impact that ulceration places on the patient. The aim of this study was to assess objective and subjective factors by measuring the short-term effect of CUSEFS on the surface area of wound and on pain levels in patients with venous leg ulcers (VLUs). Our study findings demonstrate that the combined treatment was effective in initiating wound healing and reducing levels of pain in chronic, stagnant, recalcitrant venous leg ulcers.

The effect of hyperbaric oxygen therapy on the pathophysiology of skin aging: a prospective clinical trial.

INTRODUCTION: Skin biopsies can be used to evaluate physiological effects of aging targeted intervention at the tissue/cellular levels. Recent clinical trials have shown that hyperbaric oxygen therapy (HBOT) can target aging hallmarks, including telomere shortening, senescent cells clearance and angiogenesis. The aim of this study was to evaluate the effects of HBOT on the skin of a normal, non-pathological, aging population. METHODS: The study was performed as a prospective clinical trial. After signing informed consent and undergoing baseline evaluations, the subjects were assigned to a three-month control period followed by three months of HBOT daily sessions. Skin biopsies were taken at baseline, after three months of no intervention (control) and 1-2 weeks following the last HBOT session. Trichrome, Orecin, lipofuscin and CD31 staining were used to evaluate collagen fibers, elastic fibers, senescent cells and blood vessels, respectively. RESULTS: Out of the cohort of 70 participants in the normal aging population study, thirteen male patients (age 68.07±2.5y) gave consent for repeated skin biopsies. Following HBOT, there was a significant increase in collagen density (p<0.001, effect size(es)=1.10), elastic fiber length (p<0.0001, es=2.71) and the number of blood vessels (p=0.02, es=1.00). There was a significant decrease in fiber fragmentation (p=0.012) and in tissue senescent cells (p=0.03, es=0.84) post-HBOT. No changes were noted in elastic fiber density or thickness. CONCLUSIONS: The study indicates, for the first time in humans, that HBOT can significantly modulate the pathophysiology of the skin aging in a healthy aging population. The demonstrated mechanisms include angiogenesis and senescent cell clearance.

Comprehensive approach in surgical reconstruction of facial nerve paralysis: a 10-year perspective.

Facial paralysis presents diverse functional and aesthetic abnormalities. Reconstruction may be achieved by several methods. We reviewed the management and outcome of facial paralysis patients to establish principles on which a comprehensive reconstructive approach may be based. Records were reviewed of all patients operated for facial paralysis at our institution between 1998 and 2007. Ninety-five patients were included, of which 15 patients had static reconstruction alone, and 80 patients had dynamic reconstruction. Presented is our experience in reconstruction of facial paralysis over the past decade, delineating a comprehensive approach to this condition. Various surgical techniques are described.

A Novel Recombinant Human Collagen-based Flowable Matrix for Chronic Lower Limb Wound Management: First Results of a Clinical Trial.

BACKGROUND: Chronic ulcers pose a significant health concern and economic burden. Numerous products, including animal-derived collagen products, have been designed to provide the injured site with a biocompatible structural matrix that promotes tissue regeneration. Yet, animal-derived collagens can evoke immune responses, bear risk of disease transmission, and fail to closely mimic the function of native collagen. OBJECTIVE: This study aims to assess the safety and performance of a novel flowable wound matrix, formulated from tobacco plant-purified fibrillated recombinant human type I collagen (rhCollagen), in patients with chronic lower limb ulcers. MATERIALS AND METHODS: This single-arm, open-label, multicenter trial took place at 5 treatment centers. Wounds were photographed and preliminary surgical debridement was performed prior to rhCollagen application. Patients received a single application of rhCollagen to the wound bed, followed by weekly assessments of the wound. RESULTS: Twenty patients (mean age, 63 years), presenting with a chronic ulcer of neuropathic (45%), posttraumatic (35%), postoperative (10%), and venous (10%) origin, underwent rhCollagen treatment. Initial wound area ranged between 0.2 cm3 to 9.2 cm3. At 4-weeks posttreatment, median wound area reduction was 94%. Fifteen ulcers exhibited ≥ 70% wound closure, 9 of which achieved complete closure. Only 1 participant suffered a local self-resolving wound infection. No significant device-related adverse events were reported throughout the study. CONCLUSIONS: A single, easy-to-use rhCollagen flowable gel application for chronic lower limb ulcers may promote wound closure with minimal adverse events.

Fabrication of very high aspect ratio metal nanowires by a self-propulsion mechanism.

A novel synthesis method of very high aspect ratio metal nanowires is described. The synthesis utilizes a nanoporous membrane as a template and self-electrophoresis as a directed force that continuously push formed nanowires out of the pores in a rate that is identical to the rate of their elongation. As a result, while the pores of membranes are only 6 microm long, the formed nanowires could be more than 100 microm long.