The chemical composition and sources of road dust, and of tire and road wear particles-A review.

To gain better understanding of how the transition to electric vehicles affects road dust (RD) composition, and potential health and environmental risks, it is crucial to analyze the chemical composition of RD and identify its sources. Sources of RD include wear of tire tread (TT), brake wear (BW) and road wear (RW). A relevant component of RD are tire and road wear particles (TRWPs). This literature review compiles data on the chemical bulk composition of RD sources, RD in Asia, Europe and North America and TRWP as a RD component. The focus is on elements such as Cd, Co, Cr, Cu, Ni, Pb, V, and Zn. Although the comparability of global RD data is limited due to differences in sampling and analytical methods, no significant differences in the composition from Asia, Europe, and North America were found for most of the investigated elements studied, except for Cd, Co, and V. Sources of RD were analyzed using elemental markers. On average TT, BW, and RW contributed 3 %, 1 %, and 96 %, respectively. The highest concentrations of TT (9 %) and BW (2 %) were observed in the particle size fraction of RD ≤ 10 µm. It is recommended that these results be verified using additional marker compounds. The chemical composition of TRWPs from different sources revealed that (i) TRWPs isolated from a tunnel dust sample are composed of 31 % TT, 6 % BW, and 62 % RW, and (ii) test material from tire test stands show a similar TT content but different chemical bulk composition likely because e.g., of missing BW. Therefore, TRWPs from test stands need to be chemically characterized prior to their use in hazard testing to validate their representativeness.

Impact of sex on severe asthma: a cross-sectional retrospective analysis of UK primary and specialist care.

INTRODUCTION: After puberty, females are more likely to develop asthma and in a more severe form than males. The associations between asthma and sex are complex with multiple intrinsic and external factors. AIM: To evaluate the sex differences in the characteristics and treatment of patients with severe asthma (SA) in a real-world setting. METHODS: Demographic, clinical and treatment characteristics for patients with SA in the UK Severe Asthma Registry (UKSAR) and Optimum Patient Care Research Database (OPCRD) were retrospectively analysed by sex using univariable and multivariable logistic regression analyses adjusted for year, age and hospital/practice. RESULTS: 3679 (60.9% female) patients from UKSAR and 18 369 patients (67.9% female) from OPCRD with SA were included. Females were more likely to be symptomatic with increased Asthma Control Questionnaire-6 (UKSAR adjusted OR (aOR) 1.14, 95% CI 1.09 to 1.18) and Royal College of Physicians-3 Question scores (OPCRD aOR 1.29, 95% CI 1.13 to 1.47). However, they had a higher forced expiratory volume in 1 second per cent (FEV1%) predicted (UKSAR 68.7% vs 64.8%, p<0.001) with no significant difference in peak expiratory flow. Type 2 biomarkers IgE (UKSAR 129 IU/mL vs 208 IU/mL, p<0.001) and FeNO (UKSAR 36ppb vs 46ppb, p<0.001) were lower in females with no significant difference in blood eosinophils or biological therapy. Females were less likely to be on maintenance oral corticosteroids (UKSAR aOR 0.86, 95% CI 0.75 to 0.99) but more likely to be obese (UKSAR aOR 1.67, 95% CI 145 to 1.93; OPCRD SA aOR 1.46, 95% CI 1.34 to 1.58). CONCLUSIONS: Females had increased symptoms and were more likely to be obese despite higher FEV1% predicted and lower type 2 biomarkers with consistent and clinically important differences across both datasets.

Cell-free plasma next-generation sequencing assists in the evaluation of secondary pneumonia in patients with COVID-19: a case series.

Secondary pneumonia occurs in 8-24% of patients with Coronavirus 2019 (COVID-19) infection and is associated with increased morbidity and mortality. Diagnosis of secondary pneumonia can be challenging. The purpose of this study was to evaluate the use of plasma microbial cell free DNA sequencing (mcfNGS) in the evaluation of secondary pneumonia after COVID-19. We performed a single-center case series of patients with COVID-19 who underwent mcfNGS to evaluate secondary pneumonia and reported the organisms identified, concordance with available tests, clinical utility, and outcomes. In 8/13 (61%) cases, mcfNGS detected 1-6 organisms, with clinically significant organisms identified in 4 cases, including Pneumocystis jirovecii, and Legionella spp. Management was changed in 85% (11/13) of patients based on results, including initiation of targeted therapy, de-escalation of empiric antimicrobials, and avoiding contingent escalation of antifungals. mcfNGS may be helpful to identify pathogens causing secondary pneumonia, including opportunistic pathogens in immunocompromised patients with COVID-19. However, providers need to carefully interpret this test within the clinical context.

Pedicled Latissimus Dorsi Flap for Extensive Scalp Reconstruction in Acute Burns.

Extensive full-thickness head and neck burn defects represent some of the greatest challenges because of the exposure of burned calvaria and lack of good local reconstructive options. This study reports the use of a pedicled latissimus dorsi (LD) muscle flap to cover a large full-thickness scalp burn defect measuring 20 × 15 cm, including 15 × 13.7 cm of bone exposure and extending from the posterior neck to the mastoid and vertex of the scalp. The authors discuss the technique to safely maximize the reach, which includes distal dissection to the iliac crest and thoracolumbar fascia, dissection of the pedicle to the axillary vessels, tunnel creation through the pectoralis major muscle, re-attachment of the LD origin to the pectoralis major and teres major, and undermining of the neck skin and subcutaneous tissue to avoid damage of the accessory nerve. This case highlights the reach of a pedicled LD muscle flap for extensive scalp reconstruction for defects all the way to the vertex and beyond. The size and reliability of the LD muscle makes it a valuable alternative for large scalp defects for cases of complex scalp reconstruction in patients deemed not ideal candidates for free flap reconstruction.

Integrating health intervention into existing program structure of the neglected tropical diseases: lessons learned from Yobe and Ebonyi states.

Background: Nigeria has a national policy on neglected tropical diseases (NTD) which is coordinated by the Federal Ministry of Health and integrated into the health system at all government levels. A network of grassroots mobilizers, named community drug distributors (CDDs), deliver NTD drugs and commodities to rural and hard-to-reach communities throughout Nigeria. Methods: Interviews with state and local government coordinators of Nigerian NTD programs and focus group discussions with CDDs in Yobe and Ebonyi states were conducted to understand the working modalities of NTD programs in Nigeria to identify the potential of leveraging the NTD structure for additional health interventions such as COVID-19 vaccine rollouts. Collected data was coded and managed on NVivo version 12 using content analysis. Results and discussion: The study found that the NTD committee had the following: a structured planning and coordination process, a community mobilization approach for the effective delivery of routine Mass Administration of Medication (MAM) activities. Challenges encountered included little or no incentives for the CDDs, insecurity, transportation and logistics, and lack of equipment and drug commodities. Nigerian NTD health structures have a wide reach, with a presence in all states and local government areas (LGAs), and this has previously been leveraged to deliver commodities and interventions to rural and hard-to-reach communities for non-NTD health programs and could thus be used similarly for COVID-19 vaccination programs. The enablers of integrating health interventions into the NTD structure are increased availability of finances and manpower, while lack of financial incentives and partners' buy-in were identified as possible. challenges. Conclusion: The study suggests that integrating COVID-19 interventions into the NTD program in Nigeria would be a significant accomplishment, as the existing structure can support future interventions. The study also highlights the efficiency of the NTD program's modalities and processes, indicating that an organized structural system for public health interventions can. increase the services of existing interventions while allowing for the integration of future interventions.

Tailoring of TiAl6V4 Surface Nanostructure for Enhanced In Vitro Osteoblast Response via Gas/Solid (Non-Line-of-Sight) Oxidation/Reduction Reactions.

An aging global population is accelerating the need for better, longer-lasting orthopaedic and dental implants. Additive manufacturing can provide patient-specific, titanium-alloy-based implants with tailored, three-dimensional, bone-like architecture. Studies using two-dimensional substrates have demonstrated that osteoblastic differentiation of bone marrow stromal cells (MSCs) is enhanced on surfaces possessing hierarchical macro/micro/nano-scale roughness that mimics the topography of osteoclast resorption pits on the bone surface. Conventional machined implants with these surfaces exhibit successful osseointegration, but the complex architectures produced by 3D printing make consistent nanoscale surface texturing difficult to achieve, and current line-of-sight methods used to roughen titanium alloy surfaces cannot reach all internal surfaces. Here, we demonstrate a new, non-line-of-sight, gas/solid-reaction-based process capable of generating well-controlled nanotopographies on all open (gas-exposed) surfaces of titanium alloy implants. Dense 3D-printed titanium-aluminum-vanadium (TiAl6V4) substrates were used to evaluate the evolution of surface nanostructure for development of this process. Substrates were either polished to be smooth (for easier evaluation of surface nanostructure evolution) or grit-blasted and acid-etched to present a microrough biomimetic topography. An ultrathin (90 ± 16 nm) conformal, titania-based surface layer was first formed by thermal oxidation (600 °C, 6 h, air). A calciothermic reduction (CaR) reaction (700 °C, 1 h) was then used to convert the surface titania (TiO2) into thin layers of calcia (CaO, 77 ± 16 nm) and titanium (Ti, 51 ± 20 nm). Selective dissolution of the CaO layer (3 M acetic acid, 40 min) then yielded a thin nanoporous/nanorough Ti-based surface layer. The changes in surface nanostructure/chemistry after each step were confirmed by scanning and transmission electron microscopies with energy-dispersive X-ray analysis, X-ray diffraction, selected area electron diffraction, atomic force microscopy, and mass change analyses. In vitro studies indicated that human MSCs on CaR-modified microrough surfaces exhibited increased protein expression associated with osteoblast differentiation and promoted osteogenesis compared to unmodified microrough surfaces (increases of 387% in osteopontin, 210% in osteocalcin, 282% in bone morphogenic protein 2, 150% in bone morphogenic protein 4, 265% in osteoprotegerin, and 191% in vascular endothelial growth factor). This work suggests that this CaR-based technique can provide biomimetic topography on all biologically facing surfaces of complex, porous, additively manufactured TiAl6V4 implants.

Nanobodies as allosteric modulators of Parkinson's disease-associated LRRK2.

Mutations in the gene coding for leucine-rich repeat kinase 2 (LRRK2) are a leading cause of the inherited form of Parkinson's disease (PD), while LRRK2 overactivation is also associated with the more common idiopathic form of PD. LRRK2 is a large multidomain protein, including a GTPase as well as a Ser/Thr protein kinase domain. Common, disease-causing mutations increase LRRK2 kinase activity, presenting LRRK2 as an attractive target for drug discovery. Currently, drug development has mainly focused on ATP-competitive kinase inhibitors. Here, we report the identification and characterization of a variety of nanobodies that bind to different LRRK2 domains and inhibit or activate LRRK2 in cells and in in vitro. Importantly, nanobodies were identified that inhibit LRRK2 kinase activity while binding to a site that is topographically distinct from the active site and thus act through an allosteric inhibitory mechanism that does not involve binding to the ATP pocket or even to the kinase domain. Moreover, while certain nanobodies completely inhibit the LRRK2 kinase activity, we also identified nanobodies that specifically inhibit the phosphorylation of Rab protein substrates. Finally, in contrast to current type I kinase inhibitors, the studied kinase-inhibitory nanobodies did not induce LRRK2 microtubule association. These comprehensively characterized nanobodies represent versatile tools to study the LRRK2 function and mechanism and can pave the way toward novel diagnostic and therapeutic strategies for PD.

Keratinocyte-Macrophage Crosstalk by the Nrf2/Ccl2/EGF Signaling Axis Orchestrates Tissue Repair.

Unveiling the molecular mechanisms underlying tissue regeneration provides new opportunities to develop treatments for diabetic ulcers and other chronic skin lesions. Here, we show that Ccl2 secretion by epidermal keratinocytes is directly orchestrated by Nrf2, a prominent transcriptional regulator of tissue regeneration that is activated early after cutaneous injury. Through a unique feedback mechanism, we find that Ccl2 from epidermal keratinocytes not only drives chemotaxis of macrophages into the wound but also triggers macrophage expression of EGF, which in turn activates basal epidermal keratinocyte proliferation. Notably, we find dysfunctional activation of Nrf2 in epidermal keratinocytes of diabetic mice after wounding, which partly explains regenerative impairments associated with diabetes. These findings provide mechanistic insight into the critical relationship between keratinocyte and macrophage signaling during tissue repair, providing the basis for continued investigation of the therapeutic value of Nrf2.

Optimizing Genetic Diagnosis of Neurodevelopmental Disorders in the Clinical Setting.

Progress in medical genetics has changed the practice of medicine in general and child neurology in particular. A genetic diagnosis has become critically important in determining optimal management of many neurodevelopmental disorders, making genetic testing a routine consideration of patient care in outpatient and inpatient settings. Today's child neurologists should be familiar with various genetic testing modalities and their appropriate use. Molecular genetic testing of children with unexplained developmental delays and/or congenital anomalies has a 20% to 30% chance of identifying a causative etiology. Newer methods have made genetic testing more widely available and sensitive but also more likely to produce ambiguous results.

Production of osteogenic and angiogenic factors by microencapsulated adipose stem cells varies with culture conditions.

Growth factors produced by stem cells aid in the bone repair process. We investigated the ability of encapsulated rat adipose-derived stem cells (rASCs) treated with osteogenic media (OM) to produce growth factors, and determined the optimal combination of OM components that will lead to the production of both osteogenic and angiogenic factors. Our results demonstrate that microencapsulated stem cells were able to produce vascular endothelial growth factor (VEGF), fibroblast growth factor-2, and bone morphogenetic protein-2 (BMP2) necessary for bone regeneration. OM led to the reduction of angiogenic factors; however, the removal of dexamethasone restored angiogenic factor production. Additionally, we determined whether the effect of dexamethasone on VEGF and BMP2 varied among rat, rabbit, mouse, and humans. Dexamethasone led to a reduction in VEGF levels in ASCs derived from rats, mice, and humans, while this reduction was absent in rabbit ASCs (rbASCs). Human ASCs (hASCs) from donors of different race and sex showed a similar response to dexamethasone with secreted VEGF levels. BMP2 levels secreted by rbASCs, mouse ASCs (mASCs), and hASCs were independent of the media treatments, while rASCs responded differently in the surrounding media and within the microbeads. In conclusion, microencapsulated ASCs can be treated to produce osteogenic and angiogenic factors for tissue regeneration applications, but outcomes may vary with culture conditions.

Revisiting the Reverse Sural Artery Flap in Distal Lower Extremity Reconstruction: A Systematic Review and Risk Analysis.

BACKGROUND: The reverse sural artery flap (RSAF) is a popular option for patients with distal lower extremity defects who are not ideal candidates for free flap reconstruction. This is the first systematic review and pooled analysis of surgical characteristics, risk factors, and outcomes of the RSAF. METHODS: A systematic literature review was conducted. All studies reporting on patients undergoing RSAF reconstruction and their outcomes were included. Outcomes were pooled and analyzed using Fisher exact or χ test. RESULTS: Forty-three studies (479 patients, 481 flaps) were analyzed. The majority of patients were male (70.3%), and average ± SD age was 46.9 ± 16.7 years. Rates of smoking, diabetes mellitus (DM), and peripheral vascular disease (PVD) were 34.6%, 35.4%, and 12.3%, respectively. Defect etiologies were largely traumatic (60.4%). The most common defect location was the heel (40.8%). Flap modifications were reported in 123 flaps (25.6%). The most common modification was adipofascial extension (20.3%).Overall, the partial and total flap loss rates were 15.4% and 3.1%, respectively. Partial flap loss was significantly increased in smokers (28.9% vs 12.2% in nonsmokers, P = 0.0195). Technical modifications decreased the odds of partial necrosis by almost 3-fold compared with traditional RSAF reconstruction (7.2% vs 17.9%; odds ratio, 2.8 [1.4-5.8]; P = 0.0035). Patient age, DM, and PVD were not significantly associated with flap loss. CONCLUSIONS: The RSAF remains a safe salvage option for patients with DM or PVD but should be used with caution in smokers. Technical modifications to minimize pedicle compression significantly reduce rates of partial necrosis.

Subcutaneous-Only Gluteal Fat Grafting: A Prospective Study of the Long-Term Results with Ultrasound Analysis.

In recent years, gluteal fat augmentation has exhibited some of the most significant growth among all plastic surgery procedures. However, as the popularity of and media attention to gluteal fat augmentation continue to rise, reports of fatalities, largely attributed to fat embolism, have raised valid concerns. Many plastic surgeons inject fat in the intramuscular plane and claim better graft take in the muscles and the possibility of injecting more volume in the gluteal region. Because of the large caliber of vessels, subcutaneous fat augmentation has been a preference of many. However, the long-term outcome of fat injected into the subcutaneous layer has been questionable, and there is a lack of prospective quantitative studies of subcutaneous-only fat grafting. Therefore, the authors evaluated the long-term maintenance of gluteal adipose thickness when fat was injected only subcutaneously. Fifty consecutive female patients were evaluated in this prospective clinical study. All patients underwent gluteal fat augmentation in the subcutaneous plane only. Ultrasound analysis of the adipose tissue thickness of the gluteal region was performed preoperatively, immediately postoperatively, and at 12 months postoperatively. Immediate postoperative measurements revealed an average increase in gluteal subcutaneous layer thickness of 56.51 percent (range, 39.5 to 108.6 percent) (p < 0.0001). At 12 months postoperatively, the gluteal adipose tissue thickness decreased by an average of 18.16 percent (range, 6.8 to 24.8 percent) (p < 0.0001). Subcutaneous-only gluteal fat augmentation is shown to be as effective as previous studies reporting intramuscular fat injection with regard to long-term fat retention in the buttocks. CLINICAL QUESTION/LEVEL OF EVIDENCE:: Therapeutic, IV.

Diabetes is not associated with increased rates of free flap failure: Analysis of outcomes in 6030 patients from the ACS-NSQIP database.

BACKGROUND: Diabetes affects a significant proportion of the population in the United States. Microsurgical procedures are common in this patient population, and despite many conflicting reports in the literature, there are no large studies evaluating the direct association between diabetes and outcomes, specifically failure, following free flap reconstruction. In this study, we sought to determine the impact of diabetes on postoperative outcomes following free flap reconstruction using a national multi-institutional database. METHODS: We reviewed the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database to identify patients undergoing free flap reconstruction from 2010 to 2015. Preoperative variables and outcomes were compared between diabetic and nondiabetic patients. Univariate and multivariate analyses were performed to control for confounders. RESULTS: We identified 6030 eligible patients. No significant difference in flap failure rates was observed. However, diabetic patients presented significantly higher rates of wound complications, including deep incisional surgical site infection (SSI) (OR = 1.35; P = .01) and wound dehiscence (OR = 1.17; P = .03). Diabetic patients also presented a significantly longer hospital length of stay (LOS) (ß = .62; P < .001). CONCLUSIONS: Our study evaluated the largest national cohort of free flap procedures. These results suggest that diabetes is not associated with increased rates of flap failure. However, diabetic patients are at significantly higher risk of postoperative deep incisional SSI, wound dehiscence, and longer LOS. Our findings provide the most concrete evidence to date in support of free flap reconstruction in diabetic patients, but highlight the need for heightened clinical vigilance and wound care for optimal outcomes.

A Prospective, Randomized, Blinded Trial Comparing Digital Simulation to Textbook for Cleft Surgery Education.

BACKGROUND: Simulation is progressively being integrated into surgical training; however, its utility in plastic surgery has not been well described. The authors present a prospective, randomized, blinded trial comparing digital simulation to a surgical textbook for conceptualization of cleft lip repair. METHODS: Thirty-five medical students were randomized to learning cleft repair using a simulator or a textbook. Participants outlined markings for a standard cleft lip repair before (preintervention) and after (postintervention) 20 minutes of studying their respective resource. Two expert reviewers blindly graded markings according to a 10-point scale, on two separate occasions. Intrarater and interrater reliability were calculated using intraclass correlation coefficients. Paired and independent t tests were performed to compare scoring between study groups. A validated student satisfaction survey was administered to assess the two resources separately. RESULTS: Intrarater grading reliability was excellent for both raters for preintervention and postintervention grading (rater 1, intraclass correlation coefficient = 0.94 and 0.95, respectively; rater 2, intraclass correlation coefficient = 0.60 and 0.92, respectively; p < 0.001). Mean preintervention performances for both groups were comparable (0.82 ± 1.17 versus 0.64 ± 0.95; p = 0.31). Significant improvement from preintervention to postintervention performance was observed in the textbook (0.82 ± 1.17 versus 3.50 ± 1.62; p < 0.001) and simulator (0.64 ± 0.95 versus 6.44 ± 2.03; p < 0.001) groups. However, the simulator group demonstrated a significantly greater improvement (5.81 ± 2.01 versus 2.68 ± 1.49; p < 0.001). Participants reported the simulator to be more effective (p < 0.001) and a clearer tool (p < 0.001), that allowed better learning (p < 0.001) than textbooks. All participants would recommend the simulator to others. CONCLUSION: The authors present evidence from a prospective, randomized, blinded trial supporting online digital simulation as a superior educational resource for novice learners, compared with traditional textbooks.

Current Management of Self-Inflicted Wounds in Surgery: A Critical Review.

OBJECTIVE: Despite the presence of self-inflicted wounds (SIWs) across all of medicine, our current understanding of SIWs in surgery is limited. Here, we detail the pertinent aspects of the history, diagnosis, decision making, and management of SIWs as they relate to the field of surgery. In addition, we present the first comprehensive review of SIWs across the surgical literature. SUMMARY BACKGROUND DATA: Self-inflicted wounds have been recognized for much of recorded human history and span a wide spectrum of patient behaviors, motivations, and underlying psychiatric illnesses. METHODS: We performed a comprehensive literature review of SIWs in the surgical literature. In total, 189 articles were identified. RESULTS: The most common site of primary SIW was the upper extremity (36.2%), and the most common presenting injuries were lacerations (22.7%). Forty-two percent of patients had received prior surgical procedures for their SIWs, and the average length of time preceding treatment or diagnosis of an injury as an SIW was 2.29 years. Self-inflicted wounds resulting from foreign body insertions were most common (25.9%). Psychiatric factors accounted for most SIW production (35%), of which factitious disorder was the most common (12.7%). Other motivations for SIW production included autoeroticism (8.6%), substance related (6.6%), organic brain disease (5.0%), and self-therapy/surgery by patients (1.7%). Surgical management was ultimately required for nearly 75% of SIWs and was successful in most cases. CONCLUSIONS: Self-inflicted wounds are frequently encountered in all surgical specialties and encompass many anatomic locations, presentations, and patient-motivating factors. Surgical intervention is common, and successful outcomes are often achieved.

Abdominal Panniculectomy: Determining the Impact of Diabetes on Complications and Risk Factors for Adverse Events.

BACKGROUND: The prevalence of obesity along with bariatric surgery and massive weight loss requiring panniculectomy is increasing in the United States. The effect of diabetes mellitus on outcomes following panniculectomy remains poorly defined despite its prevalence. This study aims to evaluate the impact of diabetes mellitus on complications following panniculectomy and determine risk factors for adverse events. METHODS: The American College of Surgeons National Surgical Quality Improvement Program database was used to identify patients undergoing panniculectomy between 2010 and 2015. Patients were stratified based on diabetes status. RESULTS: Review of the database identified 7035 eligible patients who underwent panniculectomy, of which 770 (10.9 percent) were diabetic. Multivariate regression showed that diabetes mellitus was a significant risk factor for wound dehiscence (OR, 1.92; 95 percent CI, 1.41 to 3.15; p = 0.02). Obesity was a significant risk factor for superficial (OR, 2.78; 95 percent CI, 1.53 to 3.69; p < 0.001) and deep (OR, 1.52; 95 percent CI, 1.38 to 3.97; p = 0.01) incisional surgical-site infection. Smokers were also at an increased risk for superficial (OR, 1.42; 95 percent CI, 1.19 to 1.75; p = 0.03) and deep (OR, 1.63; 95 percent CI, 1.31 to 2.22; p = 0.02) incisional surgical-site infection. CONCLUSIONS: Diabetes mellitus is an independent risk factor for wound dehiscence following panniculectomy. Obesity and smoking were significant risk factors for superficial and deep incisional surgical-site infection. These results underscore the importance of preoperative risk factor evaluation in patients undergoing panniculectomy for safe outcomes. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.

Effects of Tunable Keratin Hydrogel Erosion on Recombinant Human Bone Morphogenetic Protein 2 Release, Bioactivity, and Bone Induction.

IMPACT STATEMENT: Recombinant human bone morphogenetic protein 2 (rhBMP-2) delivery from collagen sponges for bone formation is an important clinical example of growth factors in tissue engineering. Side effects from rhBMP-2 burst release and rapid collagen resorption have led to investigation of alternative carriers. Here, keratin carriers with tunable erosion rates were formulated by varying disulfide crosslinking via ratios of oxidatively (keratose) to reductively (kerateine) extracted keratin. In vitro rhBMP-2 bioactivity increased with kerateine content, reaching levels greater than with collagen. Heterotopic bone formation in a mouse model depended on the keratin formulation, highlighting the importance of the growth factor carrier.

Assessing the Value of a Multimedia-Based Aesthetic Curriculum in Plastic Surgery Residency: A Single-Center Pilot Study.

BACKGROUND: Although global demand for cosmetic surgery continues to rise, plastic surgery residents feel that current models of aesthetic training are inadequate in preparing them for future practice. Digital learning resources offer promising educational possibilities, yet there are no formal studies investigating the integration of these technologies into the aesthetic curriculum. OBJECTIVES: Here, we review the current state of aesthetic training for plastic surgery residents and present a pilot study investigating the value of a dedicated multimedia-based aesthetic curriculum at a single, large academic program. METHODS: Twenty plastic surgery residents participated in an 8-week curriculum consisting of weekly multimedia-based modules covering a specific aesthetic topic. Participants completed pre- and post-intervention surveys at 0 and 10 weeks, respectively. Surveys evaluated resident perspectives of the current state of aesthetic training, confidence in performing surgical and non-surgical aesthetic procedures, perceived efficacy of multimedia interventions for learning, and preferences for inclusion of such approaches in future curricula. RESULTS: 16.7% of participants planned on entering an aesthetic fellowship following residency. The mean number of months of dedicated cosmetic surgery rotations was 1.65 months. Resident confidence level in performing a particular aesthetic procedure significantly increased in 6/14 modules. More than 90% of residents were interested in incorporating the modules into residency. CONCLUSIONS: Technology-based aesthetic training is critical for producing the finest future practitioners and leaders of this specialty. Here, we show that plastic surgery residents can benefit from a multimedia-based aesthetic curriculum, even if they do not plan on pursuing a career devoted to cosmetic surgery.

Use of Tranexamic Acid to Reduce Blood Loss in Liposuction.

BACKGROUND: The use of tranexamic acid for blood loss prevention has gained popularity in many specialties, including plastic surgery. However, its use in liposuction has not been studied. The authors present a prospective, double-blind, nonrandomized study evaluating the efficacy of tranexamic acid in reducing perioperative blood loss during liposuction. METHODS: Twenty women undergoing liposuction were divided into two cohorts. Group 1 (n = 10) received a standard dose of 10 mg/kg of tranexamic acid intravenously in the preoperative and postoperative periods, whereas group 2 (n = 10) received a placebo. Patient hematocrit levels were evaluated preoperatively and postoperatively. Blood volume in the infranatant of the lipoaspirate was also measured; t tests were used for statistical analysis. RESULTS: Age, body mass index, and volume of lipoaspirate were comparable between the two cohorts. The volume of blood loss for every liter of lipoaspirate was 56.2 percent less in the tranexamic group compared with the control group (p < 0.001). Hematocrit levels at day 7 postoperatively were 48 percent less in group 1 compared with group 2 (p = 0.001). Furthermore, a 1 percent drop in the hematocrit level was found after liposuction of 812 ± 432 ml in group 1 and 379 ± 204 ml in group 2. Thus, the use of tranexamic acid could allow for aspiration of 114 percent more fat, with comparable variation in hematocrit levels. CONCLUSIONS: Tranexamic acid has been shown to be effective for minimizing perioperative blood loss in liposuction. Further large randomized controlled studies are required to corroborate this effect. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Achievements and Challenges in Facial Transplantation.

: The first facial transplantation in 2005 ushered in a new era in reconstructive surgery, offering new possibilities for the repair of severe disfigurements previously limited by conventional techniques. Advances in allograft design, computerized preoperative planning, surgical technique, and postoperative revisions have helped push the boundaries in this new frontier of vascularized composite allotransplantation. Over the past 12 years, 40 of these procedures have been performed across the world, offering the field the opportunity to reflect on current outcomes. Successes achieved in the brief history of facial transplantation have resulted in a new set of obstacles the field must now overcome. In this review, we aim to highlight the achievements, major challenges, and future directions of this rapidly evolving field.