Targeting VPS72 inhibits ACTL6A/MYC axis activity in HCC progression.

BACKGROUND AND AIMS: HCC is a highly heterogeneous disease that is caused largely by genomic copy number variations. Herein, the mechanistic and therapeutically targeted role of vacuolar protein sorting 72 homologue (VPS72), a novel copy number variation cis-driven gained gene identified by genome-wide copy number variation and transcriptome analyses in HCC, is not well understood. APPROACH AND RESULTS: First, overexpression of VPS72 enhanced the initiation and progression of HCC in vitro and in vivo . Mechanistically, VPS72 interacted with the oncoproteins MYC and actin-like 6A (ACTL6A) and promoted the formation of the ACTL6A/MYC complex. Furthermore, ACTL6A regulated VPS72 protein stability by weakening the interaction between tripartite motif containing 21 (TRIM21) and VPS72. Thus, the interaction between VPS72 and ACTL6A enhanced the affinity of MYC for its target gene promoters and promoted their transcription, thereby contributing to HCC progression, which was inhibited by adeno-associated virus serotype 8 (AAV8)-mediated short hairpin RNA (shRNA) against VPS72. CONCLUSIONS: This study reveals the molecular mechanism of ACTL6A/VPS72/MYC in HCC, providing a theoretical basis and therapeutic target for this malignancy.

Single-staged revascularization and reconstruction after crush injury of the wrist and distal forearm: A protocolized approach.

BACKGROUND: Amputation of the wrist or distal forearm after high-energy trauma due to a crushing mechanism is associated with complex tissue defects, making repair, and reconstruction challenging. Given the difficulty of this type of salvage, patients unfortunately experience a high revision amputation rate. However, a higher quality of life has been reported in patients with successful reconstructions. Herein, we described a protocolized approach for revascularization and reconstruction for functional hand salvage after traumatic amputation from a crushing mechanism using an anterolateral thigh flap (ALT). METHODS: A retrospective review was performed between October 2016 and October 2023 for all patients who underwent single-stage emergent debridement, revascularization, and soft tissue coverage using the ALT after amputation at the level of the wrist or distal forearm secondary to high-energy crush injury. Charts were reviewed for the preoperative Mangled Extremity Salvage Score, intraoperative details including what structures were injured and the reconstructive method performed, and postoperative data such as follow-up duration, outcomes, and complications. RESULTS: Eleven patients met the inclusion criteria with an average age of 35.5 (21-49) years old. The average size of the skin soft tissue defects was 17.3 × 8 cm (range, length: 13-25 cm, width: 6-13 cm), and all cases had associated injury to the underlying bone, nerves, and blood vessels. The average size of the ALT flap used for reconstruction was 19.2 × 9.8 cm (range, length: 14-27 cm, width: 7-15 cm). All patients had survival of the replanted limb. One patient experienced partial flap necrosis that required secondary debridement and skin graft. Nine patients healed without requiring any additional debridement procedures. Patient follow-up averaged 24.6 (12-38) months. All patients achieved satisfactory functional recovery with Grade II to III of Chen's criteria. CONCLUSIONS: For patients with traumatic crush amputation to the wrist with surrounding soft tissue injury, thorough debridement, revascularization, and reconstruction of amputated limbs can be performed in a single stage using the ALT. A protocolized approach from two institutions is presented, demonstrating improved survival and reduced complications of the traumatized limb with improved long-term patient outcomes.

Significantly Improved Cold Preservation of Rat Hind Limb Vascularized Composite Allografts Using the New PrC-210 Free Radical Scavenger.

Vascularized composite allotransplantation (VCA) represents a promising reconstructive solution primarily conducted to improve quality of life. However, tissue damage caused by cold-ischemia (CI) storage prior to transplant represents a major factor limiting widespread application. This study investigates the addition of the novel free radical scavenger PrC-210 to UW Organ Preservation Solution (UW Solution) to suppress CI-induced skeletal muscle injury in a rat hind limb amputation model. Lewis rats received systemic perfusion of UW solution +/- PrC-210 (0 mM control, 10 mM, 20 mM, 30 mM, or 40 mM), followed by bilateral transfemoral amputation. Limbs were stored in 40 mL of the same perfusate at 4 °C for 48 h. Muscle punch biopsies were taken at set times over the 48 h cold-storage period and analyzed for caspase-3,7 activity, cytochrome C levels, and qualitative histology. A single 15 s perfusion of PrC-210-containing UW Solution conferred a dose-dependent reduction in CI-induced muscle cell death over 48 h. In the presence of PrC-210, muscle cell mitochondrial cytochrome C release was equivalent to 0 h controls, with profound reductions in the caspase-3,7 apoptotic marker that correlated with limb histology. PrC-210 conferred complete prevention of ROS-induced mitochondrial lysis in vitro, as measured by cytochrome C release. We conclude that the addition of 30 mM PrC210 to UW Solution conferred the most consistent reduction in CI limb damage, and it warrants further investigation for clinical application in the VCA setting.

Latex-Infused Porcine Abdominal Model: A Novel Microsurgery Simulator for Deep Inferior Epigastric Perforator Dissection.

BACKGROUND: Perforator dissection and flap elevation are routinely performed for microsurgical reconstruction; however, there is a steep learning curve to mastering these technical skills. Though live porcine models have been utilized as a microsurgical training model, there are significant drawbacks that limit their use, including cost, limited ability for repetition, and obstacles associated with animal care. Here we describe the creation of a novel perforator dissection model using latex augmented non-living porcine abdominal walls. We provide anatomic measurements that demonstrate valuable similarities and differences to human anatomy to maximize microsurgical trainee practice. METHODS: Six latex-infused porcine abdomens were dissected based on the deep cranial epigastric artery (DCEA). Dissection was centered over the abdominal wall mid-segment between the second and fourth nipple line. Dissection steps included exposure of lateral and medial row perforators, incision of anterior rectus sheath with perforator dissection, and dissection of DCEA pedicle. DCEA pedicle and perforator measurements were compared with deep inferior epigastric artery (DIEA) data in the literature. RESULTS: An average of seven perforators were consistently identified within each flap. Assembly of the model was performed quickly and allowed for two training sessions per specimen. Porcine abdominal walls demonstrate similar DCEA pedicle (2.6 ± 0.21 mm) and perforator (1.0 ± 0.18 mm) size compared with a human's DIEA (2.7 ± 0.27 mm, 1.1 ± 0.85 mm). CONCLUSION: The latex-infused porcine abdominal model is a novel, realistic simulation for perforator dissection practice for microsurgical trainees. Impact on resident comfort and confidence within a microsurgical training course is forthcoming.

Perforator Dissection Porcine Abdominal Model: A Novel Simulator to Improve Microsurgical Training.

BACKGROUND: Perforator dissection and flap elevation are routinely performed for microsurgical reconstruction; however, there is a steep learning curve to mastering these technical skills. Though live porcine models have been utilized as microsurgical training models, significant drawbacks limit their use. We recently developed a latex-perfused, nonliving, porcine abdomen perforator dissection simulation and described its anatomic similarity to the human deep inferior epigastric artery flap. The purpose was to assess the change in resident confidence in performing key operative steps of flap elevation and perforator dissection and obtain feedback on model realism and utility. METHODS: Seventeen plastic and reconstructive surgery resident physicians (postgraduate years 1-6) at a single institution participated in a perforator dissection session utilizing the simulation model. Each resident completed pre- and postactivity surveys to assess interval change in confidence in operating. The postactivity survey also asked residents to answer questions regarding their perception of the model's anatomic and surgical realism and utility in microsurgical training. RESULTS: Following a practice session using the latex-perfused, nonliving porcine abdomen, resident confidence was significantly increased in performing all key operative steps and the procedure overall (p = 0.001). All residents (n = 17, 100%) believed the model would improve "trainees' ability to perform perforator dissection in the operating room." Perforator, fascial, and pedicle anatomy were reported to be "Very" similar to human anatomy, with a median Likert score (MLS) of 4. Additionally, six out of the eight surgical steps were noted to be "Very" realistic, with only "Flap Design" and "Fascial Closure" found to be "Moderately" realistic with an MLS of 3. CONCLUSION: The latex-infused porcine abdominal model is a novel, realistic simulation for microsurgical trainee perforator dissection practice. This model offers a suitable substitute for perforator dissection practice, as its implementation within a microsurgery training course improves resident comfort and confidence.

Evaluation of a Full-Time Microsurgeon Educator on Resident Training, Research Collaboration, and Grant Funding.

BACKGROUND: The value of a fully trained microsurgeon dedicated to a laboratory setting at an academic institution is largely unknown. Microsurgery training lacks a national standard despite its highly complicated nature. Our study aims to evaluate the impact of a single laboratory-dedicated microsurgeon on the microsurgical training of integrated plastic surgery residents and collaborative efforts in research. METHOD: We devised a three-faceted microsurgical training curriculum, including a collaborative multi-institutional microsurgery course, novel high-fidelity simulator models, and a dedicated microsurgeon. We cataloged grant funding achieved through support to other divisions' protocols. Time, in hours, spent on training and the number of anastomoses completed with the microsurgical educator in a laboratory setting over a 4-year period (2017-2021) were evaluated. Resident independence scores were collected from attending microsurgeons to quantify the translation of microsurgical training. RESULTS: Purchasing and maintenance costs of rats in our rodent facility decreased by $16,533.60 as 198 rats were replaced by our models. The residents who participated in our novel microsurgical training program were able to independently perform anastomoses in the OR by their postgraduate year 6. Additionally, the surgical support offered by our laboratory-dedicated microsurgeon led to a total of $24,171,921 in grant funding between 2017 and 2020. CONCLUSION: Hiring an expert microsurgical educator to train residents in a laboratory has proved promising in accelerating microsurgical mastery. Novel training modules, alternatives to animal models, save resources in housing and animal costs. The addition of a research-oriented-microsurgeon has improved collaborative efforts to advance a range of surgical fields.

Blue-Blood Pig Thorax Model Increases Residents' Confidence in Internal Mammary Dissection.

BACKGROUND: Preparation of the recipient vessels is a crucial step in autologous breast reconstruction, with limited opportunity for resident training intraoperatively. The Blue-Blood-infused porcine chest wall-a cadaveric pig thorax embedded in a mannequin shell, connected to a saline perfusion system-is a novel, cost-effective ($55) simulator of internal mammary artery (IMA) dissection and anastomosis intended to improve resident's comfort, safety, and expertise with all steps of this procedure. The purpose of this study was to assess the effect of the use of this chest wall model on resident's confidence in performing dissection and anastomosis of the IMA, as well as obtain resident's and faculty's perspectives on model realism and utility. METHODS: Plastic surgery residents and microsurgery faculty at the University of Wisconsin were invited to participate. One expert microsurgeon led individual training sessions and performed as the microsurgical assistant. Participants anonymously completed surveys prior to and immediately following their training session to assess their change in confidence performing the procedure, as well as their perception of model realism and utility as a formal microsurgical training tool on a five-point scale. RESULTS: Every participant saw improvement in confidence after their training session in a minimum of one of seven key procedural steps identified. Of participants who had experience with this procedure in humans, the majority rated model anatomy and performance of key procedural steps as "very" or "extremely" realistic as compared with humans. 100% of participants believed practice with this model would improve residents' ability to perform this operation in the operating room and 100% of participants would recommend this model be incorporated into the microsurgical training curriculum. CONCLUSION: The Blue-Blood porcine chest wall simulator increases trainee confidence in performing key steps of IMA dissection and anastomosis and is perceived as valuable to residents and faculty alike.

Effect of Nimodipine and Botulinum Toxin A on Peripheral Nerve Regeneration in Rats: A Pilot Study.

BACKGROUND: Peripheral nerve damage is a frequent problem, with an estimated 2.8%-5.0% of trauma admissions involving peripheral nerve injury. End-to-end, tension-free microsurgical repair (neurorrhaphy) is the current gold standard treatment for complete transection (neurotmesis). While neurorrhaphy reapproximates the nerve, it does not address the complex molecular regenerative process. Evidence suggests that botulinum toxin A (BTX) and nimodipine (NDP) may improve functional recovery, but mechanisms of action remain unknown. METHODS: This research investigates BTX and NDP for their novel capacity to improve neural regeneration in the setting of neurorrhaphy using a Lewis rat tibial nerve neurotmesis model. In a triple-masked, placebo-controlled, randomized study design, we compared functional (rotarod, horizontal ladder walk), electrophysiological (conduction velocity, duration), and stereological (axon count, density) outcomes of rats treated with: NDP+saline injection, BTX+NDP, Saline+placebo, and BTX+placebo. Additional controls included sham surgery +/- BTX. RESULTS: NDP+saline outperformed other treatment groups in the ladder walk. This group had the fewest deep slips (15.07% versus 30.77% in BTX+NDP, P = 0.122), and the most correct steps (70.53% versus 55.58% in BTX+NDP, P = 0.149) in functional testing. NDP+saline also had the fastest nerve conduction velocity (0.811m/s versus 0.598m/s in BTX+NDP, P = 0.126) among treatment groups. BTX+NDP had the highest axon count (10,012.36 versus 7,738.18 in NDP+Saline, P = 0.009). CONCLUSION: This study is the first to test NDP with BTX in a multimodal assessment of nerve recovery following neurotmesis and neurorrhaphy. NDP outperformed BTX+NDP functionally. Future work will focus on nimodipine in an effort to improve nerve recovery in trauma patients.

Advanced Technical Pearls for Successful Supermicrosurgical Lymphaticovenular Anastomosis.

ABSTRACT: Lymphaticovenular anastomosis (LVA) is now accepted as one of the mainstays of surgical treatment of lymphedema. The unique advantages of LVA that set it apart from other procedures such as vascularized lymph node transfer are its safety and its minimally invasive nature. To date, there has been no report of worsening of disease as a result of LVA, even when performed unsuccessfully. Despite these notable advantages, the procedure is much less frequently performed compared with vascularized lymph node transfer because of inconsistent procedural outcome. In our experience, LVA is highly effective when performed with proper patient selection and meticulous technical execution. In this article, we share the senior author's LVA "tips and tricks" to help readers achieve greater success when performing this extraordinary supermicrosurgical procedure.

Augmentation of Chicken Thigh Model with Fluorescence Imaging Allows for Real-Time, High Fidelity Assessment in Supermicrosurgery Training.

BACKGROUND: The skills required for supermicrosurgery are hard-earned and difficult to master. The University of Wisconsin "blue-blood" chicken thigh model incorporates perfusion of the thigh vessels with a blue liquid solution, allowing users to visualize flow across their anastomoses. This model has proven to be an excellent source of small vessels (down to 0.3 mm) but assessing the quality of anastomoses at this spatial scale has proven difficult. We evaluated whether fluorescent imaging with indocyanine green (ICG) in this realistic training model would enhance the assessment of supermicrosurgical anastomoses, and therefore improve real-time feedback to trainees. METHODS: Anastomoses of vessels ranging from 0.35 to 0.55mm in diameter were performed followed by the capture of white light with and without fluorescence imaging overlay during infusion of "blue-blood" and ICG. Videos were randomized and shown to seven fellowship-trained microsurgeons at the University of Wisconsin-Madison who rated each anastomosis as "patent," "not patent," or "unsure." Surgeon accuracy, uncertainty, and inter-rater agreement were measured for each imaging modality. RESULTS: Use of fluorescence significantly increased surgeon accuracy to 91% compared with 47% with white light alone (p = 0.015), decreased surgeon uncertainty to 4% compared with 41% with white light alone (p = 0.011), and improved inter-rater agreement from 53.1% with white light alone to 91.8% (p = 0.016). CONCLUSION: Augmentation of the University of Wisconsin "blue-blood" chicken thigh model with ICG fluorescence improves accuracy, decreases uncertainty, and improves inter-rater agreement when assessing supermicrosurgical anastomoses in a training setting. This improved, real-time feedback enhances this model's value as a supermicrosurgical training tool.

The Blue-Blood Porcine Chest Wall: A Novel Microsurgery Training Simulator for Internal Mammary Vessel Dissection and Anastomosis.

BACKGROUND: Preparation of the internal mammary artery (IMA) is a critical step in autologous breast reconstruction. Intraoperatively, there is limited opportunity for residents to practice this skill. Porcine models provide highly realistic simulation for vascular surgery; however, use of live laboratory pigs is expensive, inconvenient, and offers limited opportunity for repetitive training. We aimed to develop an inexpensive and effective training model for IMA preparation. This article describes creation of a novel microsurgical model using cadaveric chest walls of Wisconsin Miniature Swine embedded in a modified mannequin thorax and augmented with a blue-blood perfusion system. METHODS: Anatomic comparison: five porcine chest walls were dissected, and various anatomic measurements were made for anatomic comparison to existing human data in the literature. Model assembly: the chest wall is prepared by cannulating the proximal and distal ends of the internal mammary vessels with angiocatheters, which are then connected to the blue-blood perfusion system. The model is assembled in four layers including: (1) a mannequin thorax with a window removed to expose the first to fourth intercostal spaces, bilaterally, (2) a layer of foam simulating fat, (3) the perfused pig chest wall, and (4) a second mannequin shell placed posteriorly for support. RESULTS: The porcine chest walls are similar to humans with regards to vessel size and location. This model can be assembled quickly, with a one-time approximate cost of $55.00, and allows for six training sessions per specimen. The model allows residents to practice the key steps of IMA preparation including dissection, elevation of perichondria, and vascular anastomosis while working at a depth that closely simulates the human thorax. Continuous blue-blood perfusion provides immediate feedback on anastomosis quality. CONCLUSION: Overall, this novel model can provide inexpensive and realistic simulation of internal mammary vessel preparation and anastomosis.

Multispecialty Microsurgical Course Utilizing the Blue-Blood Chicken Thigh Model Significantly Improves Resident Comfort, Confidence, and Attitudes in Multiple Domains.

BACKGROUND: The high level of technical skill required by microsurgical procedures has prompted the development of in vitro educational models. Current models are cost-ineffective, unrealistic, or carry ethical implications and are utilized as isolated experiences within single surgical specialties. The purpose of this study was to assess the educational and interprofessional effect of a microsurgical training course utilizing the nonliving "Blue-Blood" chicken thigh model (BBCTM) in a multidisciplinary environment. METHODS: A 10-hour course was developed integrating didactic lectures, case presentations, and one-on-one practical sessions utilizing hydrogel microvessels and the BBCTM. Pre- and postcourse surveys were administered assessing participants' self-reported comfort and confidence within fundamental microsurgical domains, assessments of the models utilized, and the effects of a multidisciplinary environment on the experience. RESULTS: A total of 19 residents attended the course on two separate occasions (n = 10 and n = 9, respectively). Respondents varied from postgraduate year-2 (PGY-2) to PGY-6+ and represented plastic and reconstructive surgery (n = 10), urology (n = 6), and otolaryngology (n = 3). On average, each participant performed 4.3 end-to-end, 1.3 end-to-side, and 0.4 coupler-assisted anastomoses. Following the course, participants felt significantly more comfortable operating a microscope and handling microsurgical instruments. They felt significantly more confident handling tissues, manipulating needles, microdissecting, performing end-to-end anastomoses, performing end-to-side anastomoses, using an anastomotic coupler, and declaring anastomoses suitable (all p < 0.05). The majority of participants believed that the use of live animals in the course would have minimally improved their learning. All but two respondents believed the course improved their awareness of the value of microsurgery in other specialties "very much" or "incredibly." CONCLUSION: A microsurgical training course utilizing nonliving models such as the "BBCTM significantly improves resident comfort and confidence in core operative domains and offers an in vivo experience without the use of live animals. Multispecialty training experiences in microsurgery are beneficial, desired, and likely underutilized.

Heterotopic Auxiliary Whole Liver Rat Transplant Model Utilizing a Hepaticoureterostomy for Allograft Rejection Studies.

Small animal transplant models are indispensable for organ tolerance studies investigating feasible therapeutic interventions in preclinical studies. Rat liver transplantation (LTx) protocols typically use an orthotopic model where the recipients' native liver is removed and replaced with a donor liver. This technically demanding surgical procedure requires advanced micro-surgical skills and is further complicated by lengthy anhepatic and lower body ischemia times. This prompted the development of a less complicated heterotopic method that can be performed faster with no anhepatic or lower body ischemia time, reducing post-surgery stress for the recipient animal. This heterotopic LTx protocol includes two main steps: excising the liver from the donor rat and transplanting the whole liver into the recipient rat. During the excision of the donor liver, the surgeon ligates the supra-hepatic vena cava (SHVC) and hepatic artery (HA). On the recipient side, the surgeon removes the left kidney and positions the donor liver with the portal vein (PV), infra-hepatic vena cava (IHVC), and bile duct facing the renal vessels. Further, the surgeon anastomoses the recipient's renal vein end to end with the IHVC of the liver and arterializes the PV with the renal artery using a stent. A hepaticoureterostomy is utilized for biliary drainage by anastomosing the bile duct to the recipient's ureter, permitting the discharge of bile via the bladder. The average duration of the transplantation was 130 min, cold ischemia duration was around 35 min, and warm ischemia duration was less than 25 min. Hematoxylin and eosin histology of the auxiliary liver from syngeneic transplants showed normal hepatocyte structure with no significant parenchymal alterations 30 days post-transplant. In contrast, 8-day post-transplant allogeneic graft specimens demonstrated extensive lymphocytic infiltration with a Banff Schema rejection activity index score of 9. Therefore, this LTx method facilitates a low morbidity rejection model alternative to orthotopic LTx.

Trigeminal or peripheral nerve stimulation improves functional outcomes of nerve recovery in a rodent forelimb gap repair model.

BACKGROUND: The hypothesis of this study was that trigeminal nerve stimulation (TNS) or peripheral nerve stimulation (PNS) could improve functional outcomes of peripheral nerve injury in a rat forelimb model when compared to control rats not receiving electrical stimulation (ES). While PNS is known to improve outcomes after nerve surgery, the role of TNS has not been explored. METHODS: Lewis rats were trained to perform a reach and grasp task before receiving a 2 mm gap repair of the ulnar and median nerves and randomized into four treatment groups: (1) sham injury, (2) nerve injury with sham ES, (3) nerve injury with PNS, and (4) nerve injury with TNS. Functional motor (median pull force and percent success in motor task) and sensory metrics (forelimb paw withdrawal thresholds) were collected both pre-injury and throughout rehabilitation. Nerves stained using Gomori's trichrome were assessed quantitatively and qualitatively. RESULTS: The sham ES group did not recover their pre-injury baseline functional outcomes. In contrast, the TNS and PNS groups fully recovered following injury, with no difference in functional outcomes between the pre-injury baseline and the final week of rehabilitation (P > 0.05, all). Histomorphology results demonstrated no quantitative difference, but qualitative differences in architecture were evident. CONCLUSIONS: Electrical stimulation of the trigeminal nerve or the injured nerve improved the functional outcomes of nerve regeneration in rodents. Histomorphology results of nerves from the TNS group support the proposed central mechanisms. This is an important step in translating this therapy as an adjunct, non-invasive treatment for high, mixed nerve injuries in humans.

Single cell RNA-sequencing identifies the effect of Normothermic ex vivo liver perfusion on liver-resident T cells.

BACKGROUND: Normothermic ex vivo liver perfusion (NEVLP) is an exciting strategy to preserve livers prior to transplant, however, the effects of NEVLP on the phenotype of tissue-resident immune cells is largely unknown. The presence of tissue-resident memory T cells (TRM) in the liver may protect against acute rejection and decrease allograft dysfunction. Therefore, we investigated the effects of NEVLP on liver TRMs and assessed the ability of anti-inflammatory cytokines to reduce TRM activation during NEVLP. METHODS: Rat livers underwent NEVLP with or without the addition of IL-10 and TGF-ß. Naïve and cold storage livers served as controls. Following preservation, TRM T cell gene expression profiles were assessed through single cell RNA sequencing (scRNA-seq). Differential gene expression analysis was performed with Wilcoxon rank sum test to identify differentially expressed genes (DEGs) associated with a specific treatment group. Using the online Database for Annotation, Visualization and Integrated Discovery (DAVID), gene set enrichment was then conducted with Fisher's exact test on DEGs to highlight differentially regulated pathways and functional terms associated with treatment groups. RESULTS: Through scRNA-seq analysis, an atlas of liver-resident memory T cell subsets was created for all livers. TRM T cells could be identified in all livers, and through scRNA-seq, DEG was identified with Wilcoxon rank sum test at FDR < 0.05. Based on the gene set enrichment analysis of DEGs using Fisher's exact test, NEVLP is associated with downregulation of multiple gene enrichment pathways associated with surface proteins. Furthermore, NEVLP with anti-inflammatory cytokines was associated with down regulation of 52 genes in TRM T cells when compared to NEVLP alone (FDR <0.05), most of which are pro-inflammatory. CONCLUSION: This is the first study to create an atlas of liver TRM T cells in the rat liver undergoing NEVLP and demonstrate the effects of NEVLP on liver TRM T cells at the single cell gene expression level.

Livestreaming Microsurgery Education: An Avenue to Expand Global Plastic Surgery.

Microsurgery is a complex subspecialty requiring fine manual dexterity and a thorough understanding of microsurgical techniques, requiring years of training to reach proficiency. On a global scale, trainees may not have access to a longitudinal microsurgery curriculum and instead attend brief courses to learn microsurgical techniques, limiting their ability to practice the nuances of microsurgery. There remains a gap in global microsurgical education for trainees to have consistent educational exposure. This article presents a novel and easy to use software-based microsurgical system for virtual microsurgical teaching. In doing so, this system provides a free-of-cost and highly accessible avenue to deliver consistent microsurgical education worldwide.

Enhanced interactions among gut mycobiomes with the deterioration of glycemic control.

BACKGROUND: The gut mycobiome is closely linked to health and disease; however, its role in the progression of type 2 diabetes mellitus (T2DM) remains obscure. Here, a multi-omics approach was employed to explore the role of intestinal fungi in the deterioration of glycemic control. METHODS: 350 participants without hypoglycemic therapies were invited for a standard oral glucose tolerance test to determine their status of glycemic control. The gut mycobiome was identified through internal transcribed spacer sequencing, host genetics were determined by genotyping array, and plasma metabolites were measured with untargeted liquid chromatography mass spectrometry. FINDINGS: The richness of fungi was higher, whereas its dissimilarity was markedly lower, in participants with T2DM. Moreover, the diversity and composition of fungi were closely associated with insulin sensitivity and pancreatic ß-cell functions. With the exacerbation of glycemic control, the co-occurrence network among fungus taxa became increasingly complex, and the complexity of the interaction network was inversely associated with insulin sensitivity. Mendelian randomization analysis further demonstrated that the Archaeorhizomycetes class, Fusarium genus, and Neoascochyta genus were causally linked to impaired glucose metabolism. Furthermore, integrative analysis with metabolomics showed that increased 4-hydroxy-2-oxoglutaric acid, ketoleucine, lysophosphatidylcholine (20:3/0:0), and N-lactoyl-phenylalanine, but decreased lysophosphatidylcholine (O-18:2), functioned as key molecules linking the adverse effect of Fusarium genus on insulin sensitivity. CONCLUSIONS: Our study uncovers a strong association between disturbance in gut fungi and the progression of T2DM and highlights the potential of targeting the gut mycobiome for the management of T2DM. FUNDINGS: This study was supported by MOST and NSFC of China.

Lutetium-Induced Ultrafine PtRu Nanoclusters with a High Electrochemical Surface Area for Direct Methanol Fuel Cells at Alleviated Temperatures.

PtRu alloys have been recognized as the state-of-the-art catalysts for the methanol oxidation reaction (MOR) in direct methanol fuel cells (DMFCs). However, their applications in DMFCs are still less efficient in terms of both catalytic activity and durability. Rare earth (RE) metals have been recognized as attractive elements to tune the catalytic activity, while it is still a world-class challenge to synthesize well-dispersed Pt-RE alloys. Herein, we developed a novel hydrogen-assisted magnesiothermic reduction strategy to prepare a highly dispersed carbon-supported lutetium-doped PtRu catalyst with ultrafine nanoclusters and atomically dispersed Ru sites. The PtRuLu catalyst shows an outstanding high electrochemical surface area (ECSA) of 239.0 m2 gPt-1 and delivers an optimized MOR mass activity and specific activity of 632.5 mA mgPt-1 and 26 A cmPt-2 at 0.4 V vs saturated calomel electrode (SCE), which are 3.6 and 3.5 times of commercial PtRu-JM and an order higher than PtLu, respectively. These novel catalysts have been demonstrated in a high-temperature direct methanol fuel cell running in a temperature range of 180-240 °C, achieving a maximum power density of 314.3 mW cm-2. The AC-STEM imaging, in situ ATR-IR spectroscopy, and DFT calculations disclose that the high performance is resulted from the highly dispersed PtRuLu nanoclusters and the synergistic effect of the atomically dispersed Ru sites with PtRuLu nanoclusters, which significantly reduces the CO* intermediates coverage due to the promoted water activation to form the OH* to facilitate the CO* removal.

Characterization of idiopathic chronic diarrhea and associated intestinal inflammation and preliminary observations of effects of vagal nerve stimulation in a non-human primate.

BACKGROUND: Diarrhea is commonly associated with irritable bowel syndrome, inflammatory bowel disease, microscopic colitis, and other gastrointestinal dysfunctions. Spontaneously occurring idiopathic chronic diarrhea is frequent in rhesus macaques, but has not been used as a model for the investigation of diarrhea or its treatment. We characterized this condition and present preliminary data demonstrating that left vagal nerve stimulation provides relief. METHODS: Stool consistency scores were followed for up to 12 years. Inflammation was assessed by plasma C-reactive protein, [18F]fluorodeoxyglucose (FDG) uptake, measured by positron emission tomography (PET), multiplex T cell localization, endoscopy and histology. The vagus was stimulated for 9 weeks in conscious macaques, using fully implanted electrodes, under wireless control. KEY RESULTS: Macaques exhibited recurrent periods of diarrhea for up to 12 years, and signs of inflammation: elevated plasma C-reactive protein, increased bowel FDG uptake and increased mucosal T helper1 T-cells. The colon and distal ileum were endoscopically normal, and histology revealed mild colonic inflammation. Application of vagal nerve stimulation to conscious macaques (10 Hz, 30 s every 3 h; 24 h a day for 9 weeks) significantly reduced severity of diarrhea and also reduced inflammation, as measured by FDG uptake and C-reactive protein. CONCLUSIONS AND INFERENCES: These macaques exhibit spontaneously occurring diarrhea with intestinal inflammation that can be reduced by VNS. The data demonstrate the utility of this naturally occurring primate model to study the physiology and treatments for chronic diarrhea and the neural control circuits influencing diarrhea and inflammation that are not accessible in human subjects.