Pectoral Nerve Blocks Under Direct Vision During Endoscopic-Assisted Transaxillary Breast Augmentation: A Novel, Effective Regional Blocking Approach.

BACKGROUND: Endoscopic-assisted transaxillary breast augmentation allows performing Pecs block under direct visualization. This study aimed to describe this new technique and demonstrat its short-term efficacy and safety with a preliminary clinical study. METHODS: Patients enrolled for transaxillary endoscopic-assisted prosthetic breast augmentation between February 2022 and March 2023 in two medical centers were included in the pectoral nerve block group. Postoperative VAS scores at 1, 4, 12, 24, 48, and 72 h, surgery duration, and the occurrence of nausea and vomiting were compared with a historical cohort of patients collected between February 2021 and January 2022 with the same inclusion criteria. RESULTS: 229 patients were included in the Pecs group and 116 patients were identified in the control group. No statistical difference was observed in patient characteristics. VAS score at postoperative 1 h and 72 h was similar between the two groups, whereas VAS score at postoperative 4 h, 12 h, 24 h and 48 h in Pecs group was significantly lower than control group. The occurrence of PONV in the Pecs group is significantly lower than in the control group. The duration of surgery is similar between the two groups. No block-related complication was observed in the Pecs group. CONCLUSION: A novel approach by combining pectoral nerve blocks with transaxillary endoscopic-assisted breast augmentation to perform blocks under direct vision was proposed and its short-term efficacy and safety was determined by this study. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A new type of dual-plane breast augmentation: Redefining parenchyma-muscle interface in high mobile glandular ptotic breast.

BACKGROUND: High mobile glandular ptotic breasts present the greatest challenge for implant breast augmentation with suboptimal outcomes occurring frequently. Here, we describe and evaluate an innovative approach for breast augmentation in this breast type. By widely disrupting and redefining the parenchyma-muscle interface, this technique offers opportunities to restore the takeoff point of the breast and improve the fullness of the upper pole, thus producing a "perkier" breast appearance. METHODS: A retrospective review was performed, and 68 patients who underwent breast augmentation with either type III dual-plane or the new approach between January 2015 and January 2021 were included. The patients were divided into two groups. The aesthetic outcome and patient satisfaction were evaluated using different 10-point rating forms. Data on demographic information, surgical details, and relative complication rates were recorded and compared. RESULTS: Upon comparing the aesthetic outcomes and satisfaction, the test group demonstrated better breast shape, nipple-areola position, upper pole contour outcome, and upper pole satisfaction. No post-operative hematoma, seroma, or infection occurred in either groups. No double-bubble deformity occurred in the test group, whereas it occurred in two patients in the control group. The rates of capsular contracture were 1.4% and 1.6%, in the test and control groups, respectively. CONCLUSIONS: The new approach is a safe surgical method with good aesthetic outcome, high patient satisfaction, and long-lasting result. This approach is a supplement to the dual-plane techniques, to realize the benefits of mastopexy and type III dual-plane breast augmentation.

3D Analysis of Breast Morphological Changes after Vertical-Scar Reduction Mammoplasty: A Prospective Study.

BACKGROUND: In addition to symptom relief, the crucial objective of reduction mammoplasty is to achieve a stable and esthetically pleasing postoperative breast shape. However, the morphological changes in breasts following reduction mammoplasty have not been comprehensively understood. In this study, we applied three-dimensional (3D) scanning technology for long-term follow-up monitoring of breast morphological changes to discern their changing trends. Our goal was to provide a reliable basis for assessing postoperative effects and determining follow-up time points. METHODS: This prospective study included patients undergoing vertical-scar reduction mammoplasty. We utilized a combination of linear measurements and 3D scanning to measure various parameters, including breast volume, breast volume distribution, nipple position, and scar length at various time points: pre-surgery, immediately post-surgery, 3-month postoperative, 6-month postoperative, and 1-year postoperative. RESULTS: A total of 115 patients were enrolled in this study. Throughout the initial 3 months of postoperative follow-up, there was a gradual reduction in breast volume, which tended to stabilize from 3 to 12 months. The nipple position showed a gradual shift both laterally, inferiorly, and posteriorly. The volume of the lower and lateral part of the breast increased gradually. Notably, at 1 year after surgery, the scar length was approximately 6.3% shorter compared to the immediate postoperative measurement. CONCLUSIONS: Our 3D analysis unveiled comprehensive changes in breast morphology: The overall breast volume shifted laterally and inferiorly, the nipple position moved laterally, inferiorly, and posteriorly, and there was a significant reduction in scar length. Concurrently, breast volume exhibited a gradual decrease and stabilization after 3 months, establishing it as a suitable follow-up point for assessing postoperative results. Additionally, surgical plans can be formulated based on the overall trend of changes in breast volume and distribution, combined with methods such as three-dimensional scanning, to enhance surgical outcomes and patient satisfaction. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to authors www.springer.com/00266 .

Unravelling the Flotation Performance of 1-Hydroxy-2-naphthyl hydroxamic Acid and Styrene Phosphonic Acid Collectors on Monazite Using Experiments and DFT Calculations.

The atomic-level structure and electronic properties of monazite were investigated using a first-principles method based on density functional theory (DFT). First, the geometric structure of monazite was optimized, followed by calculations of its Mulliken population, electron density, and density of states, which were subsequently analyzed. The findings of this analysis suggest that monazite is highly susceptible to cleavage along the {100} plane during crushing and grinding. When SPA was utilized as the collector, the recovery rate of monazite was higher than that when LF-P8 was used. The zeta potential and adsorption energy results indicated that the zeta potential after SPA adsorption tended towards negativity, and the adsorption energy was smaller, indicating that SPA exhibited stronger adsorption performance. LF-P8 was stably adsorbed on the monazite (100) surface via mononuclear double coordination. SPA was stably adsorbed on the surface of monazite (100) via binuclear double coordination. The results of this study provide valuable insights into the adsorption of monazite by commonly used flotation collectors. These findings are of substantial importance for future endeavors in designing flotation collectors capable of achieving selective monazite flotation.

Pedicle Selection and Design in Reduction Mammaplasty: The Role of Preoperative Fluorescence Imaging.

BACKGROUND: Breast reduction has a wide selection of pedicles but often relies on the surgeon's preference and experience. Necrosis of the nipple-areola complex (NAC) is a catastrophic complication of breast reduction surgery. OBJECTIVES: To solve the above problem objectively, we applied fluorescence imaging technology to the pedicle selection and design of breast reduction surgery for the first time, so that the dominant vessels of the NAC were included in the designed pedicle. METHODS: We retrospectively enrolled 120 patients with breast reduction (a total of 239 breasts). We compared 60 patients who underwent breast reduction without fluorescence imaging for pedicle selection (Group A) with 60 patients who underwent pedicle selection with fluorescence imaging (Group B). The NAC blood supply was monitored after the operation. RESULTS: In this study, 60 Group A cases (119 breasts) and 60 Group B cases (120 breasts) were analyzed. There were no statistically significant differences in patient demographic data or intraoperative resection weights. There were 7 cases of NAC necrosis in Group A (1 case of complete necrosis and 6 cases of partial necrosis), while no NAC necrosis occurred in Group B. There was a significant difference in the rate of NAC necrosis between the 2 groups. CONCLUSIONS: Preoperative fluorescence imaging can guide the selection and design of breast reduction, significantly reducing postoperative NAC blood supply obstacles and necrosis.

Preclinical toxicity evaluation of novel antibacterial contezolid acefosamil in rats and dogs.

Contezolid acefosamil (CZA) is an intravenous prodrug of oxazolidinone antibiotic contezolid (CZD). It is being developed to treat infections due to Gram-positive bacteria including multidrug-resistant pathogens, while addressing myelosuppression and neurotoxicity limitations associated with long-term use of this class of antibiotics. In vivo, CZA is rapidly deacylated into its first metabolite MRX-1352, which is then dephosphorylated to release active drug CZD. Four-week repeat-dose toxicity studies of intravenous CZA were conducted in Sprague-Dawley rats (40, 80, and 160/120 mg/kg/dose twice a day [BID]) and beagle dogs (25, 50, and 100/75 mg/kg/dose BID). The high doses administered to both rats and dogs were adjusted due to adverse effects including decreased body weight and food consumption. Additionally, a dose-dependent transient reduction in erythrocyte levels was recorded at the end of dosing phase. Importantly, no myelosuppressive reduction in platelet counts was observed, in contrast to the myelosuppression documented for standard-of-care oxazolidinone linezolid. The no-observed-adverse-effect level (NOAEL) of CZA was 80 and 25 mg/kg/dose BID in rats and dogs, respectively. Separately, 3-month neuropathological evaluation in Long-Evans rats (25, 37.5, and 50 mg/kg/dose, oral CZA, BID) demonstrated no neurotoxicity in the central, peripheral, and optical neurological systems. Toxicokinetic data from these studies revealed that CZD exposures at NOAELs were higher than or comparable with that for the intended clinical dose. These results confirm the favorable safety profile for CZA and support its clinical evaluation for long-term therapy of persistent Gram-positive infections, beyond the application for earlier oxazolidinones.

Hybrid Breast Augmentation: Double Benefit or Double Risk? A Comparative Study of 932 Cases.

BACKGROUND: The authors propose a hybrid breast augmentation (HBA) method combining implants and fat grafting and explore the outcome and safety through a retrospective, single-center, propensity score-matched, comparative study. METHODS: Outcome, satisfaction, and complications were compared between the HBA group (302 cases) and the implant-based breast augmentation (IBA) group (353 cases), and between the HBA group and the autologous fat grafting (AFG) group (277 cases). RESULTS: The mean follow-up period was 31.7 months. After propensity score matching (PSM), 270 cases were matched between the HBA and IBA groups, and 156 cases were matched between the HBA and AFG groups. Compared with the IBA group, HBA achieved higher scores of implant visibility/palpability and upper pole contour with the specialists' evaluations (before and after PSM; P < 0.05). Regarding patient satisfaction, the scores of softness (before and after PSM), smoothness of the upper pole (before PSM), and overall satisfaction (after PSM) of the HBA group were better ( P < 0.05). Implant-related complications occurred at a similar rate. Compared with the AFG group, HBA achieved higher scores of shape (before and after PSM) and symmetry (after PSM) with evaluations by specialists ( P < 0.05). The scores of shape, symmetry, and overall satisfaction in the HBA group were better (before and after PSM; P < 0.05). The HBA group showed a lower incidence of palpable cysts, fat necrosis, oil cysts, and fat calcification (before PSM; P < 0.05). CONCLUSION: When the three techniques were compared objectively, HBA presented better indices of aesthetic outcomes, satisfaction, and acceptable complications rates when compared with IBA and AFG. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Using Laser-Assisted Indocyanine Green Angiography to Assess Nipple-Areolar Complex Survival During Reduction Mammoplasty.

BACKGROUND: In reduction mammoplasty, preserving an appropriate skin flap is crucial to achieve a favorable postoperative appearance and prevent blood supply disorders in the nipple-areolar complex (NAC). Previous studies have indicated that a thinner or narrower flap is more favorable for breast shaping, but also increases the risk of blood supply disorders. Accessing the blood perfusion of the NAC and determining the critical threshold for NAC viability are essential aspects of reduction mammoplasty. OBJECTIVES: The aim of this study was to utilize indocyanine green (ICG) angiography to assess NAC perfusion during reduction mammoplasty. It also sought to identify critical thresholds of various indicators affecting NAC survival and provide guidance for skin flap trimming. METHODS: Thirty-eight patients who underwent reduction mammoplasty were included. Each patient received ICG angiography before and after skin flap trimming. Data on NAC perfusion, skin flap length, width, thickness, and other relevant indicators were collected. RESULTS: Among the patients, 5 experienced NAC blood supply disorders. Multiple linear regression analysis demonstrated that the NAC blood supply had a significant correlation with the tissue thickness at the pedicle base (P < .001) and with the length-to-width ratio across the nipple (P < .05). To optimize NAC survival and achieve favorable breast shaping, cutoff points for the thickness at the pedicle base and the length-to-width ratio across the nipple of 1.15 cm and 1.71, respectively, were established. CONCLUSIONS: ICG angiography provides an effective means to assess NAC blood supply and postoperative survival. The cutoff points established in this study help to predict the survival of the NAC and guide flap trimming.

Association Between Body Weight and Removed Weight in Women Undergoing Reduction Mammaplasty-A 17-year Retrospective Study of 1777 Breasts.

BACKGROUND: Breast hypertrophy causes physical and psychological symptoms. Reduction mammaplasty is a surgical procedure to lessen discomfort. However, there is a dispute about whether the weight of breast resection is related to body weight. This study aims to provide Chinese data and assess the association between body weight and removed weight in women undergoing reduction mammaplasty. METHODS: Retrospective data were collected from 1777 breasts in a single center in 17 years. Simple linear regression analysis was performed to establish whether removed weight and removed weight ratio (removed weight/body weight) correlated with the body weight. The correlations were then analyzed again after grouping according to the removed weight. RESULTS: For all breasts included, removed weight or ratio positively correlates with body weight. When the removed weight is more than 1000g, there is no statistically significant correlation between body weight and removed breast weight. When removed per breast weight is more than 600g, there is no correlation between body weight and removed breast weight ratio. CONCLUSIONS: The correlation between body weight and removed weight or ratio decreased with increasing removed weight. When removed weight >600g, the degree of breast hypertrophy is not related to body shape. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 . Therapeutic study.

What Can We Learn from Breast Implant Explantation: a 28-Year, Multicenter Retrospective Study of 1004 Explantation Cases.

BACKGROUND: Implant-based breast augmentation remains popular, but the controversy over the safety and longevity of implants has continued. An event-based analysis of reasons for implant explantation may provide us with some insight into the controversy. METHODS: Data from May 1994 to October 2022 of explantation cases from aesthetic breast augmentation in three medical centers were retrospectively reviewed. Patient characteristics, time to explantation, reasons for visit, the major reason for explantation and intraoperative findings were analyzed. RESULTS: A total of 522 patients with 1004 breasts were included in our study. Objective explantation reasons accounted for 34.0% in primary augmentation breasts and 47.6% in revision augmentation breasts, which were significantly different (p = 0.006). The most common complaint was dissatisfaction with breast appearance, followed by concerns about implant safety, poor hand feeling and pain. 43.5% of the implants worn for more than 10 years were removed for objective reasons, which was found significantly different with the proportion of objective reasons in implants removed within 1 year and 1-5 years postoperatively (p < 0.008). CONCLUSION: The proportion of different reasons for implant explantation varies across the times of surgeries and the years that the implant had been worn. As the years of implant wearing increase, the proportion of subjective reasons decreases in implant removal cases and objective reasons increase among them. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Manipulating of P2/O3 Composite Sodium Layered Oxide Cathode through Ti Substitution and Synthesis Temperature.

P2/O3 composite sodium layered oxide has emerged as a promising cathode for high-performance Na-ion batteries. However, it has been challenging to regulate accurately the phase ratio of P2/O3 composite due to their high compositional diversity, which brings about some difficulty in manipulating the electrochemical performance of P2/O3 composite. Here, we explore the effect of Ti substitution and the synthesis temperature on the crystal structure and Na storage performance of Na0.8Ni0.4Mn0.6O2. The investigation indicates Ti-substitution and altering synthesis temperature can rationally manipulate the phase ratio of P2/O3 composite, thereby purposefully regulating the cycling and rate performance of P2/O3 composite. Typically, O3-rich Na0.8Ni0.4Mn0.4Ti0.2O2-950 shows excellent cycling stability with a capacity retention of 84% (3C, 700 cycles). By elevating the proportion of P2 phase, Na0.8Ni0.4Mn0.4Ti0.2O2-850 displays concurrently improved rate capability (65% capacity retention at 5 C) and comparable cycling stability. These findings will help guide the rational design of high-performance P2/O3 composite cathodes for sodium-ion batteries.

Enabling an Excellent Ordering-Enhanced Electrochemistry and a Highly Reversible Whole-Voltage-Range Oxygen Anionic Chemistry for Sodium-Ion Batteries.

Though considerable Mg-doped layered cathodes have been exploited, some new differences relative to previous reports can be concluded by doping a heavy dose of Mg via two rational strategies. Unlike the common unit cell of the P63/mmc group by X-ray diffraction, neutron diffraction reveals a large supercell of the P63 group and enhanced ordering for Na11/18Mg1/18[Ni1/4Mg1/9Mn11/18]O2 with Mg occupying both the Na and Mn sites. Compared with only one obvious voltage plateau of Na0.5[Ni0.25Mn0.75]O2 (NNM), Na11/18Mg1/18[Ni1/4Mg1/9Mn11/18]O2 (NMNMM) shows more severe voltage plateaus but with excellent electrochemical performance. Na0.5[Mg0.25Mn0.75]O2 (NMM) with Mg only occupying the Ni site displays a highly reversible whole-voltage-range oxygen redox chemistry and smooth voltage curves without any voltage hysteresis. Cationic Ni2+/Ni4+ couples are responsible for the charge compensations of NNM and NMNMM, while only the oxygen anionic reaction accounts for the capacity of NMM between 2.5 and 4.3 V. Interestingly, the Mn3+/Mn4+ pair contributes all capacity for all cathodes between 1.5 and 2.5 V. All cathodes undergo a double-phase mechanism: an irreversible P2-O2 phase transition for NNM, an enhanced reversible P2-O2 phase transition for NMNMM, and a highly reversible P2-OP4 phase transition for NMM. In addition, the designed cathodes display excellent rate capability and long-term cycling stability but with a large difference in the various voltage ranges of 2.5-4.3 and 1.5-2.5 V, respectively. This work provides a good understanding of ion doping and some new insights into exploiting high-performance materials.

Analgesic Efficacy of Pectoral Nerve Blocks in Implant-Based Mammoplasty: A Systematic Review and Meta-Analysis.

OBJECTIVE: To evaluate the analgesic effect of pectoral nerve block in implant-based mammoplasty. METHODS: EMbase, PubMed, Web of science, MEDLINE, CNKI, Wanfang Database, VIP and other databases were searched from establishment to February 2022 by computer to collect randomized controlled trials which applied pectoral nerve block in implant-based mammoplasty, and meta-analysis was conducted after data extraction and quality evaluation of the literature meeting the inclusion criteria. RESULTS: A total of 336 patients in seven RCT studies were included in this study. Pectoral nerve block has a significant effect on postoperative analgesia in patients with implant-based mammoplasty with 1h VAS score significantly reduced in the resting state (MD=-1.85, 95%CI: -2.64~-1.07, P<0.00001); VAS score was significantly decreased 4-6 hours after operation (MD=-1.51, 95%CI: -2.47~-0.55, P=0.002); postoperative opioid consumption was reduced (SMD=-1.37, 95%CI: -2.51~-0.24, P=0.02) in PECS block group; and the incidence of postoperative nausea and vomiting in the PECS block group was significantly lower (RR: 0.30, 95 %CI: 0.19-0.38, P<0.00001). CONCLUSIONS: The application of PECS block in submuscular implant-based mammoplasty can effectively reduce the degree of acute postoperative pain, opioid consumption and the incidence of postoperative nausea and vomiting, indicating its broad prospects in clinical application. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Unraveling the Synergistic Effect of Mg and Ti Codoping to Realize an Ordered Structure and Excellent Performance for Sodium-Ion Batteries.

Layered cathodes have been recognized as potential advanced candidates for sodium-ion batteries (SIBs), but the poor electrochemical performance has seriously hindered their further development. Herein, an ordered Na2/3[Ni2/9Mg1/9Mn5/9Ti1/9]O2 (NMMT) is designed and investigated as a high-performance cathode for SIBs through the synergistic effect of Mg and Ti codoping. Compared to the single Mg- or Ti-doped materials, NMMT clearly exhibits superstructure ordering diffraction peaks, and neutron diffraction further confirms that the diffraction peaks can be well indexed by a larger supercell P63, rather than the common unit cell P63/mmc by X-ray diffraction (XRD). High-resolution transmission electron microscopy also approves the ordering arrangement. This material shows an obvious capacity activation process during the first cycles, thus delivering 113 mA h g-1 specific capacity at 0.1 C (close to the theoretical value). Excellent rate capability even at 15 C and cycling stability after 500 cycles between 2.0 and 4.3 V can also be achieved, indicating that an ordered cathode is still promising. Besides, a single-phase reaction mechanism is revealed by ex situ/in situ XRD experiments. This study offers some insights into the material design and characterization of layered oxide cathodes for high-performance SIBs in the future.

A novel prophylactic Chinese parachute ankle brace.

BACKGROUND: The objective is to compare the effects of a self-designed and self-manufactured novel prophylactic ankle brace [Chinese parachute ankle brace (CPAB)] and two ordinary ankle braces on the ankle joint during a half-squat parachute landing (HSPL) via biomechanical assessment. METHODS: Twenty elite paratroopers were in four different conditions: no brace, elastic brace, semi-rigid brace, and CPAB. Each participant was instructed to jump off a platform with three different heights, 40, 80, and 120 cm, and land on the force plate in a half-squat posture. The vertical ground reaction forces (vGRFs), joint angles, moments, powers, and works were calculated. After the experiment, every participant completed the questionnaires designed for this study. RESULTS: Increasing the dropping height increased all of the parameters significantly (P<0.01), except for time to peak vGRF (T-PvGRF). Applying three braces can all slightly increase vGRF (P=0.237) and reduce T-PvGRF by 6-10 ms, as well as decrease the joint angles, velocities, and moments on the sagittal and coronal planes. Wearing CPAB and a semi-rigid brace more efficiently restricted dorsiflexion and inversion (P<0.05), and they both significantly reduced ankle work (t=5.107, P<0.01; t=3.331, P<0.01) and peak power (t=7.237, P<0.01; t=6.711, P<0.01) at 120 cm. The total scores from low-to-high were semi-rigid brace (19.20±2.99), elastic brace (21.91±3.25), and CPAB (23.37±3.08). CONCLUSIONS: The CPAB was more effective at restricting ankle joint motion on the coronal and sagittal planes than the other two prophylactic ankle braces. Therefore, the CPAB had the advantages of a novel appearance, high efficiency, and superior comfort, providing a reliable choice for parachute jumping and training in China.

D-serine reduces memory impairment and neuronal damage induced by chronic lead exposure.

Although exogenous D-serine has been applied as a neural regulatory intervention in many studies, the role played by D-serine in hippocampal injuries caused by lead exposure remains poorly understood. Rat models of chronic lead exposure were established through the administration of 0.05% lead acetate for 8 weeks. Simultaneously, rats were administered 30 or 60 mg/kg D-serine, intraperitoneally, twice a day. Our results showed that D-serine treatment shortened the escape latency from the Morris water maze, increased the number of times that mice crossed the original platform location, and alleviated the pathological damage experienced by hippocampal neurons in response to lead exposure. Although D-serine administration did not increase the expression levels of the N-methyl-D-aspartate receptor subtype 2B (NR2B) in the hippocampi of lead-exposed rats, 60 mg/kg D-serine treatment restored the expression levels of NR2A, which are reduced by lead exposure. These findings suggested that D-serine can alleviate learning and memory impairments induced by lead exposure and that the underlying mechanism is associated with the increased expression of NR2A in the hippocampus. This study was approved by the Animal Ethics Committee of North China University of Science and Technology, China (approval No. LX2018155) on December 21, 2018.

Exosomes Derived from Bone Mesenchymal Stem Cells with the Stimulation of Fe3O4 Nanoparticles and Static Magnetic Field Enhance Wound Healing Through Upregulated miR-21-5p.

BACKGROUND: Both magnetic nanoparticles (MNPs) and exosomes derived from bone mesenchymal stem cells (BMSC-Exos) have been reported to improve wound healing. In this study, novel exosomes (mag-BMSC-Exos) would be fabricated from BMSCs with the stimulation of MNPs and a static magnetic field (SMF) to further enhance wound repair. METHODS: Mag-BMSC-Exos, namely, exosomes derived from BMSCs preconditioned with Fe3O4 nanoparticles and a SMF, together with BMSC-Exos were both first isolated by ultracentrifugation, respectively. Afterwards, we conducted in vitro experiments, including scratch wound assays, transwell assays, and tube formation assays, and established an in vivo wound healing model. The miRNA expression profiles were compared between BMSC-Exos and mag-BMSC-Exos to detect the potential mechanism of improving wound healing. At last, the function of exosomal miR-21-5p during wound healing was confirmed by utilizing a series of gain- and loss-of-function experiments in vitro. RESULTS: The optimal working magnetic condition was 50 µg/mL Fe3O4 nanoparticles combined with 100 mT SMF. In vitro, mag-BMSC-Exo administration promoted proliferation, migration and angiogenesis to a greater extent than BMSC-Exo administration. Local transplantation of mag-BMSC-Exos into rat skin wounds resulted in accelerated wound closure, narrower scar widths and enhanced angiogenesis compared with BMSC-Exo transplantation. Notably, miR-21-5p was found to be highly enriched in mag-BMSC-Exos and served as a critical mediator in mag-BMSC-Exo-induced regulatory effects through inhibition of SPRY2 and activation of the PI3K/AKT and ERK1/2 signaling pathways. CONCLUSION: Mag-BMSC-Exos can further enhance wound healing than BMSC-Exos by improving angiogenesis and fibroblast function, and miR-21-5p upregulation in mag-BMSC-Exos might be the potential mechanism. This work offers an effective and promising protocol to improve wound healing in clinic.

Posterior only instrumented fusion provides incomplete curve control for early-onset scoliosis in type 1 neurofibromatosis.

BACKGROUND: The mid-long term outcomes of posterior spinal fusion in pediatric neurofibromatosis type 1 (NF-1) patients are rarely reported, so does the effectiveness of itsorthopeidc maintenance function. This study aims to evaluate the mid-long term surgical outcomes of posterior only instrumented spinal fusion for early-onset scoliosis (EOS) in NF-1 patients. METHODS: A retrospective review was performed on a cohort of 10 NF-1 patients having EOS from 2008 to 2014 in our hospital, the age averaged at 7.8 years old when they underwent posterior only instrumented spinal fusion for their EOS. Both general clinical data and surgical specific data of the patients were collected and reviewed, and the dystrophic progression of EOS was evaluated during the follow-up. RESULTS: The average duration of follow-up was 54 months (24 to 88 months). All patients underwent posterior only instrumented spinal fusion at 1 stage. The primary curves of EOS were thoracic in 9 cases and 1 patient had lumbar scoliosis. Preoperative major curve was significantly corrected (from 66.1 to 31.1 degrees). However, the major curve deteriorated significantly to 40.1 degrees on average at the end of the follow-up. The T1-S1 distance increased 2.8 cm on average and kept increasing at a rate of 0.6 cm/year during the follow-up. CONCLUSIONS: Posterior only fusion surgery was not a good option to treat the EOS in NF-1 patients despite the relatively short segments involvement in the disease. The maintenance of orthopedic effect after treatment was not satisfactory.

Different Effects of Al Substitution for Mn or Fe on the Structure and Electrochemical Properties of Na0.67Mn0.5Fe0.5O2 as a Sodium Ion Battery Cathode Material.

P2-type layered oxides based on the elements Fe and Mn have attracted great interest as sodium ion battery (SIB) cathode materials owing to their inexpensive metal constituents and high specific capacity. However, they suffer from rapid capacity fading and complicated phase transformations. In this study, we modulate the crystal structure and optimize the electrochemical performances of Na0.67Mn0.5Fe0.5O2 by Al doping for Mn or Fe, respectively, and the roles of Al in the enhancement of the rate capability and cycling performance are unraveled. (1) The substitution of Al for Mn or Fe decreases the lattice parameters a and c but enlarges d spacing and lengthens Na-O bonds, which enhances Na+ diffusion and rate capability especially for Na0.67Mn0.5Fe0.47Al0.03O2. (2) Al doping reduces the thickness of TMO2 and strengthens TM-O/O-O bonding. This enhances the layered structure stability and the capacity retention. (3) Al doping mitigates Mn3+ and Jahn-Teller distortion, mitigating the irreversible phase transition. (4) Al doping also alleviates the lattice volume variation and the structure strain. This further improves the stability of the layered structure and the cycling performances particularly in the case of Al doping for Fe. The in-depth insights into the roles of Al substitution might be also useful for designing high-performance cathode materials for SIBs through appropriate lattice doping.