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The mammalian liver's regenerative ability has led researchers to engineer animals as incubators for expansion of human hepatocytes. The expansion properties of human hepatocytes in immunodeficient...

Background We evaluated the effectiveness of a simple, low-cost educational brochure in improving disposal rates of unused opioids after outpatient upper extremity surgery. Methods This cross-sectional study enrolled eligible adult patients from a peripheral nerve clinic between November 2017 and September 2018. Patients either received or did not receive the educational brochure, which outlined a simple method to dispose of unused opioids and completed a survey at 2 weeks after surgery. We compared the proportion of patients who disposed of unused opioids after surgery between the group that had received the brochure and the group that had not. Categorical data were analyzed with χ2 test, proportions data with binomial tests, and numerical data with Mann-Whitney U test, all with a significance level of P < .05. Results There were 339 survey respondents. Nineteen patients who did not meet inclusion criteria were excluded. Of the 320 remaining patients, 139 received the brochure and 181 did not. An additional 55 patients were excluded due to preoperative opioid use. Overall, 35.3% of recipients and 38.3% of those who did not receive the brochure used all of their prescribed opioid medication ( P = .625; confidence interval = −14.6%-8.8%). Among patients with unused opioid medication, a significantly higher proportion of brochure recipients disposed of the medicine compared with those who did not receive the brochure (46.7% vs 19.6%, P < .001). Conclusions Distribution of an educational brochure significantly improved disposal of unused opioids after surgery. This easily implemented intervention can improve disposal of unused opioids and ultimately decrease excess opioids available for diverted use in the community.

Background: Therapeutic electrical stimulation (ES) applied to repaired nerve is a promising treatment option to improve regeneration. However, few studies address the impact of ES following nerve graft reconstruction. The purpose of this study was to determine if ES applied to a nerve repair using nerve isograft in a rodent model could improve nerve regeneration and functional recovery. Methods: Adult rats were randomized to 2 groups: “ES” and “Control.” Rats received a tibial nerve transection that was repaired using a tibial nerve isograft (1.0 cm length), where ES was applied immediately after repair in the applicable group. Nerve was harvested 2 weeks postrepair for immunohistochemical analysis of axon growth and macrophage accumulation. Independently, rats were assessed using walking track and grid-walk analysis for up to 21 weeks. Results: At 2 weeks, more robust axon regeneration and greater macrophage accumulation was observed within the isografts for the ES compared to Control groups. Both walking track and grid-walk analysis revealed that return of functional recovery was accelerated by ES. The ES group demonstrated improved functional recovery over time, as well as improved recovery compared to the Control group at 21 weeks. Conclusions: ES improved early axon regeneration into a nerve isograft and was associated with increased macrophage and beneficial M2 macrophage accumulation within the isograft. ES ultimately improved functional recovery compared to isograft repair alone. This study supports the clinical potential of ES to improve the management of nerve injuries requiring a nerve graft repair.

Summary A reliable source of human hepatocytes and transplantable livers is needed. Interspecies embryo complementation, which involves implanting donor human stem cells into early morula/blastocyst stage animal embryos, is an emerging solution to the shortage of transplantable livers. We review proposed mutations in the recipient embryo to disable hepatogenesis, and discuss the advantages of using fumarylacetoacetate hydrolase knockouts and other genetic modifications to disable hepatogenesis. Interspecies blastocyst complementation using porcine recipients for primate donors has been achieved, although percentages of chimerism remain persistently low. Recent investigation into the dynamic transcriptomes of pigs and primates have created new opportunities to intimately match the stage of developing animal embryos with one of the many varieties of human induced pluripotent stem cell. We discuss techniques for decreasing donor cell apoptosis, targeting donor tissue to endodermal structures to avoid neural or germline chimerism, and decreasing the immunogenicity of chimeric organs by generating donor endothelium., In this article, Nyberg and colleagues discuss the possibility of generating human livers through interspecies blastocyst complementation, review candidate hepatogenesis-disabling mutations in recipient blastocysts with a focus on fumarylacetoacetate hydrolase knockouts as an advantageous model, and present recent advances in blastocyst complementation to improve the effectiveness and ethics of interspecies hepatogenesis.

Background Women seldom reach the highest leadership positions in academic plastic surgery. Contributing factors include lack of female role models/mentors and lack of gender diversity. Studies show that female role models and mentors are critical for recruiting and retaining female surgeons and that gender diversity within organizations more strongly influences women's career choices. The authors therefore sought to determine the current gender diversity of academic plastic surgery programs and investigate influences of gender and leadership on program gender composition. Methods A cross-sectional study of U.S. plastic surgery residency programs was performed in December of 2018. Genders of the leadership were collected, including medical school dean, department of surgery chair, department/division of plastic surgery chair/chief, plastic surgery program director, plastic surgery faculty, and plastic surgery residents. Gender relationships among these groups were analyzed. Results Ninety-nine residency programs were identified (79 integrated with or without independent and 20 independent). Women represented a smaller proportion of academic plastic surgeons in more senior positions (38 percent residents, 20 percent faculty, 13 percent program directors, and 8 percent chairs). Plastic surgery chair gender was significantly correlated with program director gender, and plastic surgery faculty gender was significantly associated with plastic surgery resident gender. Although not statistically significant, female plastic surgery chair gender was associated with a 45 percent relative increase in female plastic surgery residents. Conclusions Women in leadership and gender diversity influence the composition of academic plastic surgery programs. Gender disparity exists at all levels, worsening up the academic ladder. Recruitment, retention, and promotion of women is critical, as such diversity is required for continued progress in innovation and problem-solving within plastic surgery.

Optimal treatment of patients with various types of liver tumors or certain liver diseases frequently demands major liver resection, which remains a clinical challenge especially in children. Eighty seven consecutive pediatric liver resections including 51 (59%) major resections (resection of 3 or more hepatic segments) and 36 (41%) minor resections (resection of 1 or 2 segments) were analyzed. All patients were treated between January 2010 and March 2018. Perioperative outcomes were compared between major and minor hepatic resections. The male to female ratio was 1.72:1. The median age at operation was 20 months (range, 0.33–150 months). There was no significant difference in demographics including age, weight, ASA class, and underlying pathology. The surgical management included functional assessment of the future liver remnant, critical perioperative management, enhanced understanding of hepatic segmental anatomy, and bleeding control, as well as refined surgical techniques. The median estimated blood loss was 40 ml in the minor liver resection group, and 90 ml in major liver resection group (P

Repair of traumatic nerve injuries can require graft material to bridge the defect. The use of alternatives to bridge the defect, such as acellular nerve allografts (ANAs), is becoming more common and desired. Although ANAs support axon regeneration across short defects (3 cm), axon regeneration across longer defects (3 cm) is limited. It is unclear why alternatives, including ANAs, are functionally limited by length. After repairing Lewis rat nerve defects using short (2 cm) or long (4 cm) ANAs, we showed that long ANAs have severely reduced axon regeneration across the grafts and contain Schwann cells with a unique phenotype. But additionally, we found that long ANAs have disrupted angiogenesis and altered leukocyte infiltration compared to short ANAs as early as 2 weeks after repair. In particular, long ANAs contained fewer T cells compared to short ANAs. These outcomes were accompanied with reduced expression of select cytokines, including IFN-γ and IL-4, within long versus short ANAs. T cells within ANAs did not express elevated levels of IL-4, but expressed elevated levels of IFN-γ. We also directly assessed the contribution of T cells to regeneration across nerve grafts using athymic rats. Interestingly, T cell deficiency had minimal impact on axon regeneration across nerve defects repaired using isografts. Conversely, T cell deficiency reduced axon regeneration across nerve defects repaired using ANAs. Our data demonstrate that T cells contribute to nerve regeneration across ANAs and suggest that reduced T cells accumulation within long ANAs could contribute to limiting axon regeneration across these long ANAs.

Cell therapies using immune cells or non-parenchymal cells of the liver have emerged as potential treatments to facilitate immunosuppression withdrawal and to induce operational tolerance in liver transplant (LT) recipients. Recent pre-clinical and clinical trials of cellular therapies including regulatory T cells, regulatory dendritic cells, and mesenchymal cells have shown promising results. Here we briefly summarize current concepts of cellular therapy for induction of operational tolerance in LT recipients.

This case report describes an isolated radial nerve avulsion in a pediatric patient, treated by combination sensory and motor median to radial nerve transfers. After traumatic avulsion of the proximal radial nerve, a 12-year-old male patient underwent end-to-end transfer of median nerve branches to flexor carpi radialis and flexor digitorum superficialis to the posterior interosseous nerve and extensor carpi radialis nerve, respectively. He underwent end-to-side sensory transfer of the superficial radial sensory to the median sensory nerve. Pronator teres to extensor carpi radialis brevis tendon transfer was simultaneously performed to power short-term wrist extension. Within months after surgery, the patient had regained 9–10/10 sensation in the hand and forearm. In the following months and years, he regained dexterity, independent fine-finger and thumb motions, and 4–5/5 strength in all extensors except the abductor pollicis longus muscle. He grew 25 cm without extremity deformity or need for secondary orthopedic procedures. In appropriate adult and pediatric patients with proximal radial nerve injuries, nerve transfers have advantages over tendon transfers, including restored independent fine finger motions, regained sensation, and reinnervation of multiple muscle groups with minimal donor sacrifice.

Background Our country is in the midst of an opioid epidemic. Although the problem is multifactorial, one issue is the presence of excess prescription opioid medications circulating in our communities. Our objective was to determine whether dissemination of an educational brochure would improve the disposal of unused opioids after surgery. Study Design Eligible surgery patients from an upper extremity/peripheral nerve clinic were enrolled into this prospective before and after study between February 2017 and September 2017. Patients who reported opioid use preoperatively were excluded from this study. The same survey was administered to the group of patients who did not receive the intervention and to those who did receive the intervention. Our primary endpoint was the proportion of patients who disposed of unused opioid medications. Results A total of 334 patients were studied: 164 who did not receive the brochure and 170 who received the brochure. Seventy-six patients were excluded for preoperative opioid use. After dissemination of the brochure, there was a significant increase in the proportion of patients who disposed of their unused opioids (11% vs 22%, p = 0.02). Of those who disposed of their opioids, there was no significant difference in the proportion of patients from each group who disposed in a manner that was recommended by the brochure (43% vs 64%, p = 0.19). Conclusions Dissemination of the educational brochure improved disposal of unused opioids after surgery. This low-cost, easily implemented intervention can improve disposal of unused opioids and ultimately, decrease the amount of excess opioids circulating in our communities.