Complications Following Tissue Expander-Based Reconstruction in Pediatric Burn Injuries: A Retrospective Analysis.

BACKGROUND: Tissue expansion has been widely used to reconstruct soft tissue defects following burn injuries in pediatric patients, allowing for satisfactory cosmetic and functional outcomes. Factors impacting the success of tissue expander (TE)-based reconstruction in these patients are poorly understood. Herein, we aim to determine the risk factors for postoperative complications following TE-based reconstruction in pediatric burn patients. METHODS: A retrospective review of pediatric patients who underwent TE placement for burn reconstruction from 2006 to 2019 was performed. Primary outcomes were major complications (TE explantation, extrusion, replacement, flap necrosis, unplanned reoperation, readmission) and wound complications (surgical site infection and wound dehiscence). Descriptive statistics were calculated. The association between primary outcomes, patient demographics, burn characteristics, and TE characteristics was assessed using the chi-squared, Fisher's exact, and Mann-Whitney U tests. RESULTS: Of 28 patients included in the study, the median [interquartile range (IQR)] age was 6.5 (3.3-11.8) years, with a follow-up of 12 (7-32) months. The majority were males [n = 20 (71%)], Black patients [n = 11 (39%)], and experienced burns due to flames [n = 78 (29%)]. Eleven (39%) patients experienced major complications, most commonly TE premature explantation [n = 6 (21%)]. Patients who experienced major complications, compared to those who did not, had a significantly greater median (IQR) % total body surface area (TBSA) [38 (27-52), 10 (5-19), P = 0.002] and number of TEs inserted [2 (2-3), 1 (1-2), P = 0.01]. Ten (36%) patients experienced wound complications, most commonly surgical site infection following TE placement [n = 6 (21%)]. Patients who experienced wound complications, compared to those who did not, had a significantly greater median (IQR) %TBSA [35 (18-45), 19 (13-24), P = 0.02]. CONCLUSION: Pediatric burn injuries involving greater than 30% TBSA and necessitating an increasing number of TEs were associated with worse postoperative complications following TE-based reconstruction.

Cervical Necrotizing Fasciitis: A Severe Sequela of Open Mandibular Fracture and Delay in Treatment.

Cervical necrotizing fasciitis (CNF) is a rare condition in the United States, with very few cases reported as a sequela of mandibular fracture. The authors describe the case of a 40-year-old man with poor oral health and no significant past medical history who developed CNF following delayed treatment of an open mandibular fracture, leading to life-threatening septic shock, thrombophlebitis of the internal jugular vein, and septic emboli to the lungs. Successful management of this patient was accomplished by serial surgical debridement, the administration of broad-spectrum antibiotics, and hemodynamic support. Eventual reconstruction was performed with external fixation of the mandible fracture and split-thickness skin grafting for the left neck and chest wound. The authors recommend early treatment of open mandibular fractures for immunocompromised patients or patients with poor oral hygiene to avoid the rare but potentially fatal complication of CNF and highlight external fixation as a useful technique in select cases of complex mandibular fractures.

Evaluation of modified frailty index for predicting post-operative outcomes after lower-extremity free-flap reconstruction.

BACKGROUND: Risk stratification for complex procedures such as microsurgical reconstruction of the lower extremities is an important part of preoperative planning and counseling. The aim of this study was to determine the effectiveness of the modified five-item frailty index (5-mFI) score, a validated tool for assessing risk in surgical patients, in predicting postoperative complications after lower extremity (LE) free flap reconstruction. METHODS: A retrospective review of the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was conducted from 2010 to 2020 on patients who underwent LE free-flap reconstruction. 5-mFI scores were calculated and patients were categorized as 5-mFI ≥2 or <2. The primary endpoint was the presence of 30-day overall complications. The secondary endpoints included 30-day readmission, need for reoperation, and need to discharge to a care facility. Comparisons were made using one-way analysis of variances, Pearson's chi-squared test, or Fisher's extract test. Multivariable logistic regression models were performed for sex, age, BMI, smoker status, operative time, and ASA classification. RESULTS: Total of 294 (61.6% males) patients were identified. Univariate analysis showed 5-mFI ≥2 had higher rates of overall complications (p = .043) and hematologic complications (p = .033). In this population, there were also higher rates of reoperation (p = .003) and discharge to care facility (p < .001). Multivariable regression models further substantiated that 5-mFI ≥2 was independently associated with increased overall complications [2.46, CI: 1.10-5.59, p = .031], hematologic complications [2.55, 1.02-6.35, p = .046], reoperation [4.55, 1.54-13.3, p = .006], and discharge to facility [2.86, 1.27-6.45, p = .011]. CONCLUSIONS: There is a strong association of 5-mFI ≥2 with adverse post-operative outcomes in male patients undergoing LE free-flap reconstruction. This can be a valuable adjunct in the counsel of patients for whom lower extremity salvage is feasible.

Concentration Scaling on Linear Viscoelastic Properties of Cellular Suspensions and Effects of Equilibrium Phase Behavior.

Concentration scaling on linear viscoelastic properties of cellular suspensions has been studied by rheometric characterisation of Phormidium suspensions and human blood in a wide range of volume fraction under small amplitude oscillatory shear experiments. The rheometric characterisation results are analysed by the time-concentration superposition (TCS) principle and show a power law scaling of characteristic relaxation time, plateau modulus and the zero-shear viscosity over the concentration ranges studied. The results show that the concentration effect of Phormidium suspensions on their elasticity is much stronger than that of human blood due to its strong cellular interactions and a high aspect ratio. For human blood, no obvious phase transition could be observed over the range of hematocrits studied here and with respect to a high-frequency dynamic regime, only one concentration scaling exponent could be identified. For Phormidium suspensions with respect to a low-frequency dynamic regime, three concentration scaling exponents in the volume fraction Region I (0.36≤ϕ/ϕref≤0.46), Region II (0.59≤ϕ/ϕref≤2.89) and Region III (3.11≤ϕ/ϕref≤3.44) are identified. The image observation shows that the network formation of Phormidium suspensions occurs as the volume fraction is increased from Region I to Region II; the sol-gel transition takes place from Region II to Region III. In combination with analysis of other nanoscale suspensions and liquid crystalline polymer solutions reported in the literature, it is revealed that such a power law concentration scaling exponent depends on colloidal or molecular interactions mediated with solvent and is sensitive to the equilibrium phase behaviour of complex fluids. The TCS principle is an unambiguous tool to give a quantitative estimation.

Surface to Perforator Index: Assessing the Importance of the Number of Perforators in Successful Harvesting of the Anterolateral Thigh Flap.

INTRODUCTION: The use of perforator flaps has become more popular with improvement of surgical technique, technology, as well as understanding of microvascular anatomy. The selection of well-perfused angiosomes is critical to the successful outcome of patients undergoing free tissue transfer. The number of perforators that are needed is dependent upon the surface area of the flap being harvested; however, there have been no studies to assess the optimal surface area supplied by each perforator. We hypothesized that the smaller the surface area supplied by each perforator correlated with fewer flap-related complications in the harvesting of the anterolateral thigh (ALT) flap. METHODS: All ALT flaps harvested from 2015 to 2021 at our institution were retrospectively reviewed. The surface area of the flap harvested was calculated as A = πab, where a is the long radius and b is the short radius of the ellipse. The surface-perforator index (SPI) was calculated for each flap by dividing the surface area of the ALT flap by the number of perforators supplying the flap. Our primary outcomes were flap-related complications that included: partial flap loss, dehiscence, and venous congestion. RESULTS: A total of 106 patients were identified. Twenty-four patients (22.6%) developed perforator-related complications. An increasing SPI and SPI to body surface area were strongly associated with development of complications (adjusted odds ratio [95% confidence interval], adjusted p: 1.02 [1.01, 1.03], < 0.001and 1.23 [1.12, 1.42], p < 0.001). An SPI of greater than 150 cm2/perforator was associated with a higher probability of complications (p < 0.001). CONCLUSION: Flap-related complications are significantly related to the number of perforators supplying the flap. The smaller the surface area supplied by a single perforator correlates with significantly fewer flap-related complications. SPI is a new index that may be used as a predictive tool to aid in identifying flaps that may be more prone to complications in free tissue transfer.

Literature Review: Robotic-Assisted Harvest of Deep Inferior Epigastric Flap for Breast Reconstruction.

INTRODUCTION: Robotic-assisted surgery is gaining popularity because of reported improvement in aesthetic outcomes while reducing the occurrence of complications compared with conventional surgical methods. Deep inferior epigastric perforator (DIEP) flap harvesting has a long track record as a viable procedure for autologous reconstruction of the breast. In this literature review, we describe the feasibility of using the robotic platform in DIEP flap harvest. METHODS: The Preferred Reporting Items for Systemic Reviews and Meta-Analysis methodology was to guide the literature review. PubMed and Scopus databases were searched from inception to June 6, 2022. The Medical Subject Heading terms and keywords used to conduct this search are as described: "Robotic AND deep inferior epigastric perforator AND Breast reconstruction." RESULTS: Seven publications, detailing a total of 56 robotic-assisted DIEP flap harvest procedures, were selected for review. Four publications used the transabdominal preperitoneal approach, whereas 2 exclusively used a totally extraperitoneal approach, and 1 compared the 2 approaches. The measured outcomes included technical feasibility of flap harvest in cadavers, viable flap harvest in live patients, harvest time and pedicle dissection time, pedicle length, fascial incision length, donor site pain, need for postoperative narcotic, donor site morbidity, and hernia formation. Overall, the reviewed articles demonstrated successful DIEP flap harvesting without the need for conversion to the conventional open procedure. Postoperative complications were minimal. Robotic DIEP flap harvest was shown to be safe and there were no reports of donor-site morbidity in the studies reviewed. The main advantages of the robotic approach include decreased postoperative pain and length of hospital stay, along with improved aesthetic outcomes. The main disadvantages are increased operative time and cost. CONCLUSIONS: Although at its current iteration, the robotic-assisted DIEP flap is feasible, it may not be practical in all settings. Furthermore, the true benefit of the robotic platform is yet to be determined, as more long-term studies are necessary.

Evaluation of different materials used for sealing of implant abutment access channel and the peri-implant sulcus microbiota: A 6-month, randomized controlled trial.

OBJECTIVE: Peri-implantitis has been attributed to a myriad of factors, including microleakage at the abutment-implant interface. Implant abutment access channel sealing materials (IACSM) are readily used in implant dentistry, with little evidence on their effect on microleakage. This study aims to evaluate the effect of IACSM on the microbial composition in the implant access channel and the peri-implant sulcus. METHODS: A total of n = 8 patients (64 implants) were included in this single-blinded, randomized controlled trial, whereas four different materials (cotton, polytetrafluoroethylene [PTFE], synthetic foam, or polyvinyl siloxane [PVS]) were randomly placed as an IACSM. Following 6 months, microbial analysis was completed on the IACSM and samples from the peri-implant sulci via PCR and high-throughput sequencing. Bacterial samples on the IACSM and in the peri-implant sulci were classified according to Socransky's microbial complexes. RESULTS: There was a preponderance of early colonizing bacteria within the IACSM, while the peri-implant sulci were dominated by Orange complex bacteria. The proportion of Red and Orange complex members on the IACSM was significantly less than in the peri-implant sulci. The proportion of Green, Yellow, and Blue complex members found on the IACSM was significantly greater than in the peri-implant sulci. Atopobium, a diverse species not included in the microbial complexes, was frequently detected in the peri-implant sulcus samples. CONCLUSIONS: No detectable effects of IACSM on the microbial community in the peri-implant sulcus or on the IACSM were identified. Variation of bacterial species was most dependent on the individual patient. No significant differences were found in the periodontal parameters between the different treatment groups.

BRCA1-associated R-loop affects transcription and differentiation in breast luminal epithelial cells.

BRCA1-associated basal-like breast cancer originates from luminal progenitor cells. Breast epithelial cells from cancer-free BRCA1 mutation carriers are defective in luminal differentiation. However, how BRCA1 deficiency leads to lineage-specific differentiation defect is not clear. BRCA1 is implicated in resolving R-loops, DNA-RNA hybrid structures associated with genome instability and transcriptional regulation. We recently showed that R-loops are preferentially accumulated in breast luminal epithelial cells of BRCA1 mutation carriers. Here, we interrogate the impact of a BRCA1 mutation-associated R-loop located in a putative transcriptional enhancer upstream of the ERα-encoding ESR1 gene. Genetic ablation confirms the relevance of this R-loop-containing region to enhancer-promoter interactions and transcriptional activation of the corresponding neighboring genes, including ESR1, CCDC170 and RMND1. BRCA1 knockdown in ERα+ luminal breast cancer cells increases intensity of this R-loop and reduces transcription of its neighboring genes. The deleterious effect of BRCA1 depletion on transcription is mitigated by ectopic expression of R-loop-removing RNase H1. Furthermore, RNase H1 overexpression in primary breast cells from BRCA1 mutation carriers results in a shift from luminal progenitor cells to mature luminal cells. Our findings suggest that BRCA1-dependent R-loop mitigation contributes to luminal cell-specific transcription and differentiation, which could in turn suppress BRCA1-associated tumorigenesis.

Not all flaps are created equal: Assessing the impact of active smoking in muscle-only versus perforator flaps for patients undergoing nonelective extremity-free tissue transfer-A case control study.

INTRODUCTION: Active smoking is known to impair wound healing following free tissue transfer for reconstruction due to its vasoconstrictive effect on the microcirculation. The aim of this study was to evaluate the impact of flap selection on flap loss, in nonelective, traumatic extremity-free soft tissue transfer in active smokers. METHODS: All patients undergoing a free tissue transfer for acute trauma of the extremity at a level I trauma center from 2011 to 2017 were identified. Breast reconstruction and osseous/osseocutaneous flaps were excluded. The study population was divided in two groups based on the type of flap used (muscle versus perforator flap). Factors known to be associated with impaired wound healing were extracted from the database. Primary outcome was major smoking related complications (complete/partial flap loss). Secondary outcomes included minor flap-related complications (infection, dehiscence) and donor site complications. The impact of smoking was assessed for the different type of flaps using multivariate analyses. RESULTS: A total of 118 flaps were identified during the study period. Out of those, 52 were perforator-based fasciocutaneous flaps, while 66 were muscle flaps. Active smoking status resulted in a statistically significant increase in the incidence of major and minor complications in the perforator flap group (36% vs. 4%, adjusted odds ratio, AOR [95%CI]: 2.31[1.48,19.30], adj-p = 0.021 and 32% vs. 17%, AOR [95% CI]: 1.23[1.11,14.31], adj-p = 0.034) but had no impact in the muscle group. CONCLUSIONS: The present study suggests a higher incidence of flap related complications in smokers when a perforator flap was selected but no impact when a muscle flap was utilized.

Impact of Blood Transfusion in Free Flap Breast Reconstruction Using Propensity Score Matching.

BACKGROUND: Microvascular thrombosis has been associated with cytokine release and inflammatory syndromes which can occur as a result of blood transfusions. This phenomenon could potentially lead to complications in breast free flap reconstruction. The aim of this study was to evaluate the impact of perioperative blood transfusion in free flap breast reconstruction using large population analysis. METHODS: The American College of Surgeons National Quality Improvement Program database was queried for delayed free flap breast reconstructions performed in 2016. The study population was divided based on perioperative blood transfusion within 24 hours of the start of the operation. Propensity score matching analysis was used to ensure homogeneity between the two study groups. Primary outcome was unplanned return to the operating room (OR) within 30 days. Secondary outcomes were readmission and complications. RESULTS: A total of 1,256 patients were identified. Out of those, 91 patients received a perioperative blood transfusion. All the patients received only one unit of PRBC within the first 24 hours. Those patients were matched with similar patients who did not receive a transfusion on a ratio of 1:3 (273 patients). Patients who received a transfusion had a significantly higher incidence of reoperation (42 vs. 10%, p < 0.001). Patients who received a transfusion were more likely to return to the OR after 48 hours from the initial operation (13 vs. 5%, p = 0.001). All returns to the OR were due to flap-related complications. Perioperative blood transfusion increased the incidence of wound dehiscence (9 vs. 2%, p = 0.041) but had no protective effect on the development of other postoperative complications. CONCLUSION: Perioperative blood transfusion in free flap breast reconstruction is associated with an increased probability of flap-related complications and subsequent return to the OR without decreasing the probability of developing other systemic postoperative complications.

Biological strategies for the prevention of periodontal disease: Probiotics and vaccines.

Probiotics have been considered as an adjunct to prevent and treat a variety of diseases. The ease of administration of probiotics and the fact that no adverse outcomes have been reported in the literature has promoted increasing interest from the research community for this preventive approach in a number of diseases, including periodontal diseases. Several preliminary human clinical trials have been conducted and have yielded promising results. Vaccination is another biological strategy considered for use in the prevention of periodontal diseases. To date, no vaccine trials have been conducted in humans to determine if this strategy would prevent alveolar bone loss or bacterial colonization by target pathogens. Although the available research appears promising, the current body of evidence is incomplete for both strategies. This review attempts to summarize the present status of these 2 biological strategies for the prevention of periodontal diseases.

Langerhans Cell Histiocytosis in an Adult: A Discussion of Epidemiology and Treatment Options.

Langerhans cell histiocytosis (LCH) is a rare disorder defined by the abnormal proliferation of Langerhans cells. While LCH can present at any age, it is classically described as a pediatric condition, and is therefore overlooked in the adult patient. Additionally, depending on tumor burden and location, LCH can manifest with a host of oral and systemic symptoms which further confuses the clinical presentation and ultimate diagnosis.The authors present a unique report of an elderly Hispanic male diagnosed with mandibular LCH who sought primary tumor excision after neoadjuvant chemotherapy. In this study, a fibula-free flap was used for subsequent reconstruction.The purpose of the study is 2-fold: to highlight the variability of LCH in both patient symptomatology and demographics, as well as the role of plastic reconstructive surgery in definitive LCH management, particularly in the setting of single system unifocal disease.

Tissue Oximetry Readings Accurately Predict Late Complications in Patients Undergoing Free Flap Breast Reconstruction: Exploring the Optimal Cut Point Value.

BACKGROUND: The use of tissue oximetry for monitoring following free tissue transfer has become a common practice across the United States to facilitate early detection of poor flap perfusion in the postoperative setting. There is no consensus on the optimal value, below which there is a higher chance of wound complications in patients undergoing free flap breast reconstruction. METHODS: Patients undergoing free flap breast reconstruction from 2015 to 2018 were retrospectively reviewed. Patients who returned to the operating room for a revision of the anastomosis were excluded from analysis. Patients were divided in two groups based on the development of late complications. Those were defined as fat necrosis, wound dehiscence, or distal flap ischemia/necrosis that developed after discharge from the hospital. Mean percutaneous oximetry readings of the first 24 hours were recorded and the mean change from the initial reading was calculated. The correlation between tissue oximetry change and development of complications was explored. RESULTS: A total of 120 patients were identified. The mean age was 53, while the mean body mass index was 33. A total of 38 patients developed late wound complication. History of smoking, diabetes mellitus, neoadjuvant radiation therapy, and the mean change of the tissue oximetry reading were identified as independent predictors of wound complications. The absolute number of the tissue oximetry reading did not predict late complications. A multivariate analysis revealed that patients who experienced a mean decrease < 15% from the initial reading during the first 24 hours were significantly more likely to develop late flap-related wound complications. CONCLUSION: In patients undergoing free tissue breast reconstruction, tissue oximetry readings do not predict late wound complications. However, the mean change at 24 hours from the initial reading does. A decrease of <15% in tissue perfusion was associated with a significant increase in the probability of developing flap-related wound complications.

Negating interfacial impedance in garnet-based solid-state Li metal batteries.

Garnet-type solid-state electrolytes have attracted extensive attention due to their high ionic conductivity, approaching 1 mS cm-1, excellent environmental stability, and wide electrochemical stability window, from lithium metal to ∼6 V. However, to date, there has been little success in the development of high-performance solid-state batteries using these exceptional materials, the major challenge being the high solid-solid interfacial impedance between the garnet electrolyte and electrode materials. In this work, we effectively address the large interfacial impedance between a lithium metal anode and the garnet electrolyte using ultrathin aluminium oxide (Al2O3) by atomic layer deposition. Li7La2.75Ca0.25Zr1.75Nb0.25O12 (LLCZN) is the garnet composition of choice in this work due to its reduced sintering temperature and increased lithium ion conductivity. A significant decrease of interfacial impedance, from 1,710 Ω cm2 to 1 Ω cm2, was observed at room temperature, effectively negating the lithium metal/garnet interfacial impedance. Experimental and computational results reveal that the oxide coating enables wetting of metallic lithium in contact with the garnet electrolyte surface and the lithiated-alumina interface allows effective lithium ion transport between the lithium metal anode and garnet electrolyte. We also demonstrate a working cell with a lithium metal anode, garnet electrolyte and a high-voltage cathode by applying the newly developed interface chemistry.

Phase Separation and Stack Alignment in Aqueous Cellulose Nanocrystal Suspension under Weak Magnetic Field.

Isotropic-nematic (I-N) transitions in cellulose nanocrystal (CNC) suspension and self-assembled structures in the isotropic and nematic phases were investigated using scattering and microscopy methods. A CNC suspension with a mass fraction of 7.4% spontaneously phase separated into an isotropic phase of 6.9% in the top layer and a nematic phase of 7.9% in the bottom layer. In both the phases, the CNC particles formed stacks with an interparticle distance being of ≈37 nm. One-dimensional small-angle neutron scattering (SANS) profiles due to both phases could be fitted using a stacking model considering finite particle sizes. SANS and atomic force microscopy studies indicate that the nematic phase in the bottom layer contains more populations of larger particles. A weak magnetic field of ≈0.5 T was able to induce a preferred orientation of CNC stacks in the nematic phase, with the stack normals being aligned with the field (perpendicular to the long axis of CNC particles). The Hermans orientation parameter, ⟨ P2⟩, was ≈0.5 for the nematic phase; it remained unchanged during the relaxation process of ≈10 h. The fraction of oriented CNC populations decreased during the relaxation; dramatic decrease occurred in the first 3 h. The top layer remained isotropic in the weak field. Polarized microscopy studies revealed that the nematic phase was chiral. Adjacent particles in a stack form a twisting angle of ≈0.6 °, resulting in a helix pitch distance of ≈22 µm.

Management of Bilateral Edentulous Mandible Fractures Through an Intraoral Approach Using CAD/CAM Technology: A Case Report.

The surgical management of edentulous mandible fractures presents unique challenges secondary to poor bone stock and the absence of dentition to assist with fracture reduction. In complex injury patterns, such as bilateral edentulous mandible fractures, an external approach is often necessary to achieve adequate reduction and adaptation of a load-bearing reconstruction plate. We report a case in which computer-assisted design/computer-assisted manufacturing (CAD/CAM) was applied as an adjunct for the acute management of bilateral edentulous mandible fractures in a 58-year-old man. CAD/CAM technology was used to fabricate a patient-specific reconstruction plate and a maxillomandibular splint, which facilitated the successful treatment of this complex injury through an intraoral approach. This case highlights the potential of CAD/CAM technology to improve operative efficiency and clinical outcomes in the acute management of complex edentulous mandible fractures.

Contemporary Management of Mandibular Fracture Nonunion-A Retrospective Review and Treatment Algorithm.

PURPOSE: Nonunion is an uncommon complication after mandibular fractures. The purpose of this investigation was to compare outcomes of patients with mandibular fracture nonunion who were treated with a 1- versus 2-stage approach and propose a pragmatic treatment algorithm for surgical management based on preoperative characteristics. MATERIALS AND METHODS: The authors conducted a retrospective study consisting of patients who presented to 2 level 1 trauma centers for the management of mandibular fracture nonunion over a 10-year period. The primary predictor variable was 1- versus 2-stage treatment. Outcomes were examined to propose a treatment algorithm. RESULTS: Eighteen patients were included in the study. The sample's mean age was 44.0 ± 19.3 years and most were men (88.9%). Mandibular angle and body accounted for 77.8% of cases. A single-stage approach was used in 13 patients (72.2%). Bone grafts or vascularized bone flaps were required in 13 patients (72.2%). Patients who required 2-stage treatments had intraoral soft tissue defects. Mean length of follow-up was 13.3 ± 20.4 months. All patients achieved bony union, with complications occurring in 5 patients (27.8%). The authors' 10-year experience was used to formulate a treatment algorithm based on bony defect size and soft tissue status, which can be used to inform optimal surgical management. CONCLUSIONS: Nonunion of mandibular fractures is an infrequent and complex condition requiring careful and deliberate surgical management. A single-stage approach is appropriate in most cases and does not negatively affect outcomes. Bony defect size and soft tissue status are essential parameters for determining the approach and timing of reconstruction.

In Situ Neutron Depth Profiling of Lithium Metal-Garnet Interfaces for Solid State Batteries.

The garnet-based solid state electrolyte (SSE) is considered a promising candidate to realize all solid state lithium (Li) metal batteries. However, critical issues require additional investigation before practical applications become possible, among which high interfacial impedance and low interfacial stability remain the most challenging. In this work, neutron depth profiling (NDP), a nondestructive and uniquely Li-sensitive technique, has been used to reveal the interfacial behavior of garnet SSE in contact with metallic Li through in situ monitoring of Li plating-stripping processes. The NDP measurement demonstrates predictive capabilities for diagnosing short-circuits in solid state batteries. Two types of cells, symmetric Li/garnet/Li (LGL) cells and asymmetric Li/garnet/carbon-nanotubes (LGC), are fabricated to emulate the behavior of Li metal and Li-free Li metal anodes, respectively. The data imply the limitation of Li-free Li metal anode in forming reliable interfacial contacts, and strategies of excessive Li and better interfacial engineering need to be investigated.

Vascular Endothelial Growth Factor Induction of Muscle-Derived Stem Cells Enhances Vascular Phenotype While Preserving Myogenic Potential.

BACKGROUND: Previous work by our group and other laboratories have revealed that muscle-derived stem cells (MDSCs) may contain both myogenic and endothelial progenitors, making MDSCs a promising option for skeletal muscle regeneration. The purpose of this study was to investigate the impact of vascular endothelial growth factor (VEGF) induction on the vascular and myogenic potential of MDSCs. METHODS: Muscle-derived stem cells were isolated from 4- to 8-week-old C57BL/6J mice using a preplate technique and recombinant human VEGFa was used as the induction agent. Cellular proliferation and migration were assessed using serial imaging and wound healing assays, respectively. Myosin heavy chain staining was performed to assess MDSC myotube formation. Vascular potential of MDSCs was measured by expression of CD31 and in vitro capillary tube formation. RESULTS: Vascular endothelial growth factor stimulation led to a dose-dependent increase in MDSC proliferation (P < 0.05) and migration kinetics (P < 0.01). Control MDSCs had low levels of baseline expression of CD31, which was significantly upregulated by VEGF stimulation. Similarly, MDSCs demonstrated a basal capability for capillary tube formation, which was significantly increased after VEGF induction as evidenced by increased branches (5.91 ± 0.58 vs 9.23 ± 0.67, P < 0.01) and total tube length (11.73 ± 0.97 vs 18.62 ± 1.57 mm, P < 0.01). Additionally, the myogenic potential of MDSCs as measured by fusion index remained unchanged with increasing concentration of VEGF up to 250 ng/mL (P = 0.77). CONCLUSIONS: Vascular endothelial growth factor induction enhances MDSC proliferation, migration, and endothelial phenotypes without negatively impacting myogenic potential. These results suggest that VEGF stimulation may improve vascularization of MDSC-based strategies for skeletal muscle regeneration.

Phosphate buffer-stabilized 0.1% chlorine dioxide oral rinse for managing medication-related osteonecrosis of the jaw.

PURPOSE: This is a review of the literature on nonsurgical treatment of non-healing medication related osteonecrosis of the jaw (MRONJ) utilizing a phosphate buffer-stabilized 0.1% chlorine dioxide mouthrinse. METHODS: A literature search in PubMed revealed only six case reports. MRONJ lesion site description, patient's medication history, the healing time, and the MRONJ treatment protocol followed by those authors were recorded. Additional literature review of the scientific mechanism, risks and benefits, safety and efficacy of the phosphate buffer-stabilized 0.1% chlorine dioxide mouthrinse was also performed and discussed. RESULTS: Many of the authors of the published case reports utilized 0.12% chlorhexidine as the initial mouthrinse, but the lesions did not decrease in size. After switching to a phosphate buffer-stabilized 0.1% chlorine dioxide mouthrinse for a duration ranging from 1-12 months, there was complete healing of the MRONJ lesions in all of the cases. The phosphate buffer-stabilized 0.1% chlorine dioxide mouthrinse can be helpful in the management of active MRONJ lesions as well as the prevention of recurrent MRONJ lesions in the susceptible patient population. CLINICAL SIGNIFICANCE: This literature review supports the use of phosphate buffer-stabilized 0.1% chlorine dioxide mouthrinse in the management of MRONJ lesions either as a first line of therapy or after 0.12% chlorhexidine had not been effective.