Background The autologous nerve graft, despite its donor site morbidity and unpredictable functional recovery, continues to be the gold standard in peripheral nerve repair. Rodent research studies have shown promising results with cell transplantation of human adipose-derived stem cells (hADSC) in a bioengineered conduit, as an alternative strategy for nerve regeneration. To achieve meaningful clinical translation, cell therapy must comply with biosafety. Cell extraction and expansion methods that use animal-derived products, including enzymatic adipose tissue dissociation and the use of fetal bovine serum (FBS) as a culture medium supplement, have the potential for transmission of zoonotic infectious and immunogenicity. Human-platelet-lysate (hPL) serum has been used in recent years in human cell expansion, showing reliability in clinical applications. Methods We investigated whether hADSC can be routinely isolated and cultured in a completely xenogeneic-free way (using hPL culture medium supplement and avoiding collagenase digestion) without altering their physiology and stem properties. Outcomes in terms of stem marker expression (CD105, CD90, CD73) and the osteocyte/adipocyte differentiation capacity were compared with classical collagenase digestion and FBS-supplemented hADSC expansion. Results We found no significant differences between the two examined extraction and culture protocols in terms of cluster differentiation (CD) marker expression and stem cell plasticity, while hADSC in hPL showed a significantly higher proliferation rate when compared with the usual FBS-added medium. Considering the important key growth factors (particularly brain-derived growth factor (BDNF)) present in hPL, we investigated a possible neurogenic commitment of hADSC when cultured with hPL. Interestingly, hADSC cultured in hPL showed a statistically higher secretion of neurotrophic factors BDNF, glial cell-derived growth factor (GDNF), and nerve-derived growth factor (NFG) than FBS-cultured cells. When cocultured in the presence of primary neurons, hADSC which had been grown under hPL supplementation, showed significantly enhanced neurotrophic properties. Conclusions The hPL-supplement medium could improve cell proliferation and neurotropism while maintaining stable cell properties, showing effectiveness in clinical translation and significant potential in peripheral nerve research.

Background Fluid Resistant Surgical Masks have been implemented in UK personal protective equipment (PPE) guidelines for COVID-19 for all care sites that do not include aerosol-generating procedures (AGPs). FFP3 masks are used in AGP areas. Concerns from the ENT and plastic surgery communities out with intensive care units have questioned this policy. Emerging evidence on cough clouds and health care worker deaths has suggested that a review is required. Aims To test the efficacy of Fluid Resistant Surgical Mask with and without adaptions for respiratory protection. To test the efficacy of FFP and FFP3 regarding fit testing and usage. Methods A smoke chamber test of 5 min to model an 8-h working shift of exposure while wearing UK guideline PPE using an inspiratory breathing mouthpiece under the mask. Photographic data were used for comparison. Results The Fluid Resistant Surgical Mask gave no protection to inhaled smoke particles. Modifications with tape and three mask layers gave slight benefit but were not considered practical. FFP3 gave complete protection to inhaled smoke but strap tension needs to be ‘just right’ to prevent facial trauma. Facial barrier creams are an infection risk. Conclusions Surgical masks give no protection to respirable particles. Emerging evidence on cough clouds and health care worker deaths suggests the implementation of a precautionary policy of FFP3 for all locations exposed to symptomatic or diagnosed COVID-19 patients. PPE fit testing and usage policy need to improve to include daily buddy checks for FFP3 users

Correspondence and Communications COVID-19 lockdown and beyond: Home practice solutions for developing microsurgical skills. Dear Sir, Current COVID-19 restrictions present significant challenges to Plastic Surgery training. Numerous obstacles exist; including the necessity for social distancing, global PPE shortages, virtual clinics decreasing trainee exposure to pathology, reduced face-to-face clinical teaching, and limited time in theatre. 1 Furthermore, suspension of nonurgent elective reconstruction work, including breast reconstruction, limits microsurgical training opportunities. Surgical training relies on multiple sequential practice sessions, to allow deep encoding into "muscle memory" 2 , this is particularly relevant for microsurgery where fine motor skills need to be developed. The authors present multiple practical and cost-effective solutions that allow trainees to practice microsurgical techniques from home and "upskill anywhere". These practice options are transferrable to other periods away from clinical practice, including research time and maternity leave, and can also be used to supplement clinical experience during unpredictable on-call rotas. In climates of economic instability, these techniques may prove particularly beneficial. A basic microsurgical instrument kit may be purchased online from multiple platforms at a relatively low cost (e.g. AliEx-press TM , £34). The cost of microsurgical sutures can be a limiting factor to microsurgical practice (e.g. 9.0 AliExpress TM , £0.93 each) and in the context of the COVID-19 pandemic, precarious supply chains necessitate preservation of resources. Luangjarmekorn et al. describe the use of human hair and insulin needles (BD Ultra-Fine Pen Needles 4 mm × 32 G, expresschemist.co.uk, £0.13 each) to make homemade microsurgical sutures (Table 1). Feedback from trainees in their study suggested that human hair sutures (Figure 1) was a "good-excellent" standard for microsurgical practice, equal to that of standard sutures 3. This is reflected in our experience; we find that a hair of dark colour, mid length, coarse texture and wavy consistency works best. There are multiple models for microsurgical practice described in the literature, including live animal models (predominantly rats), non-live animal models such as chicken wings or thighs, pig leg, placenta vessels, and cold stored vessels. Additionally, a number of non animal models exist

Background: Breast asymmetry can result from congenital or traumatic aetiologies. Breast implants, autologous fat grafting, or a combination of both of these techniques are commonly used to achieve symmetry. This study adds critical evaluation of long-term patient outcomes in a large study group, to evaluate pearls and pitfalls of these treatment modalities.Methods: A prospectively maintained database of a single surgeon experience in breast asymmetry treatment over a 13-year period (2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015)(2016)(2017)(2018) was retrospectively analysed. Breast implant surgery and fat grafting to treat asymmetry were compared in terms of number of operations to achieve symmetry, complications, and overall patient satisfaction.Results: Thirty-five patients underwent breast implant surgery, requiring an average 2.1±1.6 operations to achieve symmetry, with a major complication rate (requiring secondary procedures) of 26% (n=9). Again, 26% (n=9) were converted to lipofilling due to either implant removal or unsatisfactory results. Thirty (86%) patients underwent fat transfer monotherapy to achieve symmetry and no major complications were recorded. Nine percent (n=3) of these patients preceded to have additional implant surgery.Conclusions: Although implant-based reconstruction seemingly offers a quick single stage procedure, it is associated with significantly more revision procedures as a result of complications including capsular contracture, implant rupture and breast distortion. Fat grafting, despite requiring sequential operations to achieve initial symmetry, ultimately offers a more durable result and is associated with significantly fewer and more minor complications, while not increasing the total number of procedures required to achieve symmetry in the long term.