Functional MXenes: Progress and Perspectives on Synthetic Strategies and Structure-Property Interplay for Next-Generation Technologies.

MXenes are a class of 2D materials that include layered transition metal carbides, nitrides, and carbonitrides. Since their inception in 2011, they have garnered significant attention due to their diverse compositions, unique structures, and extraordinary properties, such as high specific surface areas and excellent electrical conductivity. This versatility has opened up immense potential in various fields, catalyzing a surge in MXene research and leading to note worthy advancements. This review offers an in-depth overview of the evolution of MXenes over the past 5 years, with an emphasis on synthetic strategies, structure-property relationships, and technological prospects. A classification scheme for MXene structures based on entropy is presented and an updated summary of the elemental constituents of the MXene family is provided, as documented in recent literature. Delving into the microscopic structure and synthesis routes, the intricate structure-property relationships are explored at the nano/micro level that dictate the macroscopic applications of MXenes. Through an extensive review of the latest representative works, the utilization of MXenes in energy, environmental, electronic, and biomedical fields is showcased, offering a glimpse into the current technological bottlenecks, such asstability, scalability, and device integration. Moreover, potential pathways for advancing MXenes toward next-generation technologies are highlighted.

Artificial Photosynthetic System with Spatial Dual Reduction Site Enabling Enhanced Solar Hydrogen Production.

Although S-scheme artificial photosynthesis shows promise for photocatalytic hydrogen production, traditional methods often overly concentrate on a single reduction site. This limitation results in inadequate redox capability and inefficient charge separation, which hampers the efficiency of the photocatalytic hydrogen evolution reaction. To overcome this limitation, a double S-scheme system is proposed that leverages dual reduction sites, thereby preserving energetic photo-electrons and holes to enhance apparent quantum efficiency. The design features a double S-scheme junction consisting of CdS nanospheres decorated with anatase TiO2 nanoparticles coupled with graphitic C3 N4 . The as-prepared catalyst exhibits a hydrogen evolution rate of 26.84 mmol g-1  h-1 and an apparent quantum efficiency of 40.2% at 365 nm. This enhanced photocatalytic hydrogen evolution is ascribed to the efficient charge separation and transport induced by the double S-scheme. Both theoretical calculations and comprehensive spectroscopy tests (both in situ and ex situ) affirm the efficient charge transport across the catalyst interface. Moreover, substituting the reduction-type catalyst CdS with other similar sulfides like ZnIn2 S4 , ZnS, MoS2 and In2 S3 further confirms the feasibility of the proposed double S-scheme configuration. The findings provide a pathway to designing more effective double S-scheme artificial photosynthetic systems, opening up fresh perspectives in enhancing photocatalytic hydrogen evolution performance.

Enhancing Photocatalytic Hydrogen Evolution by Synergistic Benefits of MXene Cocatalysis and Homo-Interface Engineering.

Photocatalytic water splitting holds great promise as a sustainable and cost-effectiveness alternative for the production of hydrogen. Nevertheless, the practical implementation of this strategy is hindered by suboptimal visible light utilization and sluggish charge carrier dynamics, leading to low yield. MXene is a promising cocatalyst due to its high conductivity, abundance of active sites, tunable terminal functional groups, and great specific surface area. Homo-interface has perfect lattice matching and uniform composition, which are more conducive to photogenerated carriers' separation and migration. In this study, a novel ternary heterogeneous photocatalyst, a-TiO2 /H-TiO2 /Ti3 C2 MXene (MXTi), is presented using an electrostatic self-assembly method. Compared to commercial P25, pristine anatase, and rutile TiO2 , as-prepared MXTi exhibit exceptional photocatalytic hydrogen evolution performance, achieving a rate of 0.387 mmol h-1 . The significant improvement is attributable to the synergistic effect of homo-interface engineering and Ti3 C2 MXene, which leads to widened light absorption and efficient carrier transportation. The findings highlight the potential of interface engineering and MXene cocatalyst loading as a proactive approach to enhance the performance of photocatalytic water splitting, paving the way for more sustainable and efficient hydrogen production.

A Kind of (t, n) Threshold Quantum Secret Sharing with Identity Authentication.

Quantum secret sharing (QSS) is an important branch of quantum cryptography. Identity authentication is a significant means to achieve information protection, which can effectively confirm the identity information of both communication parties. Due to the importance of information security, more and more communications require identity authentication. We propose a d-level (t,n) threshold QSS scheme in which both sides of the communication use mutually unbiased bases for mutual identity authentication. In the secret recovery phase, the sharing of secrets that only the participant holds will not be disclosed or transmitted. Therefore, external eavesdroppers will not get any information about secrets at this phase. This protocol is more secure, effective, and practical. Security analysis shows that this scheme can effectively resist intercept-resend attacks, entangle-measure attacks, collusion attacks, and forgery attacks.

m6A-Related lncRNAs Predict Overall Survival of Patients and Regulate the Tumor Immune Microenvironment in Osteosarcoma.

Background: m6A-related lncRNAs have demonstrated great potential tumor diagnostic and therapeutic targets. The goal of this work was to find m6A-regulated lncRNAs in osteosarcoma patients. Method: The Cancer Genome Atlas (TCGA) database was used to retrieve RNA sequencing and medical information from osteosarcoma sufferers. The Pearson's correlation test was used to identify the m6A-related lncRNAs. A risk model was built using univariate and multivariable Cox regression analysis. Kaplan-Meier survival analysis and receiver functional requirements were used to assess the risk model's performance (ROC). By using the CIBERSORT method, the associations between the relative risks and different immune cell infiltration were investigated. Lastly, the bioactivities of high-risk and low-risk subgroups were investigated using Gene Set Enrichment Analysis (GSEA). Result: A total of 531 m6A-related lncRNAs were obtained from TCGA. Seven lncRNAs have demonstrated prognostic values. A total of 88 OS patients were separated into cluster 1, cluster 2, and cluster 3. The overall survival rate of OS patients in cluster 3 was more favorable than that of those in cluster 1 and cluster 2. The average Stromal score was much higher in cluster 1 than in cluster 2 and cluster 3 (P < 0.05). The expression levels of lncRNAs used in the construction of the risk prediction model in the high-risk group were generally lower than those in the low-risk group. Analysis of patient survival indicated that the survival of the low-risk group was higher than that of the high-risk group (P < 0.0001) and the area under the curve (AUC) of the ROC curve was 0.719. Using the CIBERSORT algorithm, the results revealed that Macrophages M0, Macrophages M2, and T cells CD4 memory resting accounted for a large proportion of immune cell infiltration. By GSEA analysis, our results implied that the high-risk group was mainly involved in unfolded protein response, DNA repair signaling, and epithelial-mesenchymal transition signaling pathway and glycolysis pathway; meanwhile, the low-risk group was mainly involved in estrogen response early and KRAS signaling pathway. Conclusion: Our investigation showed that m6A-related lncRNAs remained tightly connected to the immunological microenvironment of osteosarcoma tumors, potentially influencing carcinogenesis and development. The immune microenvironment and immune-related biochemical pathways can be changed by regulating the transcription of M6A modulators or lncRNAs. In addition, we looked for risk-related signaling of m6A-related lncRNAs in osteosarcomas and built and validated the risk prediction system. The findings of our current analysis will facilitate the assessment of outcomes and the development of immunotherapies for sufferers of osteosarcomas.

Rolipram plays an anti-fibrotic effect in ligamentum flavum fibroblasts by inhibiting the activation of ERK1/2.

BACKGROUND: Fibrosis is an important factor and process of ligamentum flavum hypertrophy. The expression of phosphodiesterase family (PDE) is related to inflammation and fibrosis. This article studied the expression of PDE in hypertrophic ligamentum flavum fibroblasts and investigated whether inhibition of PDE4 activity can play an anti-fibrotic effect. METHODS: Samples of clinical hypertrophic ligamentum flavum were collected and patients with lumbar disc herniations as a control group. The collagenase digestion method is used to separate fibroblasts. qPCR is used to detect the expression of PDE subtypes, type I collagen (Col I), type III collagen (Col III), fibronectin (FN1) and transforming growth factor ß1 (TGF-ß1). Recombinant TGF-ß1 was used to stimulate fibroblasts to make a fibrotic cell model and treated with Rolipram. The morphology of the cells treated with drugs was observed by Sirius Red staining. Scratch the cells to observe their migration and proliferation. WB detects the expression of the above-mentioned multiple fibrotic proteins after drug treatment. Finally, combined with a variety of signaling pathway drugs, the signaling mechanism was studied. RESULTS: Multiple PDE subtypes were expressed in ligamentum flavum fibroblasts. The expression of PDE4A and 4B was significantly up-regulated in the hypertrophic group. Using Rolipram to inhibit PDE4 activity, the expression of Col I and TGF-ß1 in the hypertrophic group was inhibited. Col I recovered to the level of the control group. TGF-ß1 was significantly inhibited, which was lower than the control group. Recombinant TGF-ß1 stimulated fibroblasts to increase the expression of Col I/III, FN1 and TGF-ß1, which was blocked by Rolipram. Rolipram restored the increased expression of p-ERK1/2 stimulated by TGF-ß1. CONCLUSION: The expressions of PDE4A and 4B in the hypertrophic ligamentum flavum are increased, suggesting that it is related to the hypertrophy of the ligamentum flavum. Rolipram has a good anti-fibrosis effect after inhibiting the activity of PDE4. This is related to blocking the function of TGF-ß1, specifically by restoring normal ERK1/2 signal.

A Biomimetic Biphasic Scaffold Consisting of Decellularized Cartilage and Decalcified Bone Matrixes for Osteochondral Defect Repair.

It is challenging to develop a biphasic scaffold with biomimetic compositional, structural, and functional properties to achieve concomitant repair of both superficial cartilage and subchondral bone in osteochondral defects (OCDs). This study developed a biomimsubchondraletic biphasic scaffold for OCD repair via an iterative layered lyophilization technique that controlled the composition, substrate stiffness, and pore size in each phase of the scaffold. The biphasic scaffold consisted of a superficial decellularized cartilage matrix (DCM) and underlying decalcified bone matrix (DBM) with distinct but seamlessly integrated phases that mimicked the composition and structure of osteochondral tissue, in which the DCM phase had relative low stiffness and small pores (approximately 134 µm) and the DBM phase had relative higher stiffness and larger pores (approximately 336 µm). In vitro results indicated that the biphasic scaffold was biocompatible for bone morrow stem cells (BMSCs) adhesion and proliferation, and the superficial DCM phase promoted chondrogenic differentiation of BMSCs, as indicated by the up-regulation of cartilage-specific gene expression (ACAN, Collagen II, and SOX9) and sGAG secretion; whereas the DBM phase was inducive for osteogenic differentiation of BMSCs, as indicated by the up-regulation of bone-specific gene expression (Collagen I, OCN, and RUNX2) and ALP deposition. Furthermore, compared with the untreated control group, the biphasic scaffold significantly enhanced concomitant repair of superficial cartilage and underlying subchondral bone in a rabbit OCD model, as evidenced by the ICRS macroscopic and O'Driscoll histological assessments. Our results demonstrate that the biomimetic biphasic scaffold has a good osteochondral repair effect.

Comparison between tension band and cerclage with X-Plate and lag screws in treatment of comminuted patellar fractures.

BACKGROUND: Comminuted patellar fractures are not rare, and the ideal treatment method remains controversial. The present study was conducted to evaluate effects and compare complications of two different methods used to treat comminuted patellar fractures. METHODS: From March 2010 to August 2016, 102 cases of 34-C2 or 34-C3 comminuted patellar fractures were treated at our hospital, wherein patients received two different treatments: titanium cable tension band with cerclage method (group A) and intrafragmentary screws with X-shaped plating technique (group B). At follow-ups, articular step-off, range of motion (ROM), Lysholm scores, time of union, and complications were recorded and analyzed. Radiographic and clinical data as well as rate of complications were statistically analyzed. RESULTS: In total, 87 patients were included in the final analysis (n = 47 in group A and n = 40 in group B). No significant differences were noted in terms of cost of implant, age, gender, rate of 34-C3 fractures, rate of layered inferior pole fractures, postoperative articular step-off and union time. At 2-year follow-up, average Lysholm scores, ROM and rate of complications were (89.0 ± 4.5), (122°±12°) and (27.7%) in group A and (90.2 ± 3.9), (124°±11°) and (17.5%) in group B, respectively, with no significant differences (p > 0.05). The mean time of surgery in group B was shorter than that in group A with significant difference (p < 0.05). CONCLUSIONS: Treatment using the intrafragmentary screws and plate method for amenable comminuted patellar fractures achieved similar complication rate and favorable functional outcomes at the 2-year follow-up, which was comparable to the titanium cable tension band with cerclage method. Thus, the intrafragmentary screws and plate method is effective, safe and convenient for 34-C2/C3 comminuted patellar fractures, especially appropriate for patients with layered fragments.

Porous fish collagen for cartilage tissue engineering.

Cartilage defects repair is still a challenge in clinical practice until now. Although many breakthroughs have been achieved in cartilage repair using tissue engineering technology, there are still no scaffolds available for large-scale clinical applications. Currently, fish collagen (FC) is a natural source that is considered as an alternative to mammal-derived collagen in engineering cartilage tissue due to its excellent biocompatibility, suitable biodegradability, lack of immunogenicity, rich sources, low cost and minimal risk of transmitting zoonoses, which implies great potential for use in cartilage regeneration. Herein, we successfully prepared three-dimensional porous FC scaffolds from three different concentrations of FC (0.5%, 1% and 2%) by freeze-drying technology. Our results indicated that increasing the FC concentration resulted in comparable levels of suitable biodegradability and good biocompatibility but lead to a concurrent decrease in pore size and porosity and a significant increase in water absorption capacity and mechanical properties; further, initial scaffold dimension was only sustained in the 2% FC concentration. Moreover, the in vivo immunological evaluation suggested that the FC scaffold evoke low immunogenicity. In addition, our results confirmed that the porous FC scaffold facilitated cartilage formation both in vitro and when placed subcutaneously in rabbits. The gross and autopsy outcomes at 12 weeks postoperation suggested that the porous FC scaffold achieved superior cartilage repair effect than what was observed in the empty group with no scaffold. Overall, our results demonstrated that porous FC scaffolds represent a promising prospective natural material for use in engineering cartilage for clinical applications.

Exploring the Pathological Role of Collagen in Paravertebral Muscle in the Progression of Idiopathic Scoliosis.

BACKGROUND: Paravertebral muscle (PVM) is considered as a contributing factor of idiopathic scoliosis (IS); collagen is crucial for maintaining the mechanical properties of PVM, but only a few researches have described this field. In this study, we observed the muscle stiffness of PVM and the curvature of the spine by adjusting the content of collagen in PVM of rats and explored the role of collagen in the progression of IS. METHODS: 32 female Sprague Dawley rats were randomly divided into four groups: neutralizing antibody (NA) group (group 1), normal control group (group 2), IS group (group 3), and IS with NA group (group 4). TGF-ß1 NA was injected into PVM in group 1 and group 4, while Normal saline in group 2 and group 3. The Cobb angle and muscle stiffness were measured before and after injection; the rats were sacrificed at one week after injection, and performed histological, Western Blot, and qRT-PCR examinations. RESULTS: X-rays showed that scoliosis occurred in group 1 and relieved in group 4. The stiffness of PVM was decreased significantly on the convex side in group 1, while on the concave side in group 4. The expression of TGF-ß1 and COL1 on the concave side in IS rats (group 3) was significantly increased than that in normal rats (group 2), the concentration of COL1 and COL3 in group 3 was significantly higher than that in group 2, and the addition of TGF-ß1 NA significantly downregulated COL1 and COL3 in group 1 and group 4. The concentration of COL1 in convex PVM was negatively related to Cobb angle in group 1 and group 2, and in concave PVM was positively related to Cobb angle in group 3 and group 4. However, no significant correlation was found between COL3 and Cobb angle in group 3 and group 4. CONCLUSIONS: Asymmetric biomechanical characteristics of PVM was an important etiological factor of IS, which was directly correlated with collagen, it could be adjusted by local intramuscular injecting of TGF-ß1 NA, and finally had an effect on the shape of the spine.

Reducing Neuron Apoptosis in the Pontine Micturition Center by Nerve Root Transfer for Restoration of Micturition Function after Spinal Cord Injury.

OBJECTIVE: The rate of neuronal apoptosis increases after spinal cord injury (SCI). Anastomosing the normal nerve roots above the SCI level to the injured sacral nerve roots can enhance the functional recovery of neurons. Therefore, we evaluated the effect of sacral nerve root transfer after SCI on pontine neuronal survival. METHODS: Sprague-Dawley rats were randomly divided into three groups: Group A, reconstruction of afferent and efferent nerve pathways of the bladder after SCI; Group B, SCI only; and Group C, control group. We examined pontine neuronal morphology using hematoxylin and eosin (H&E) staining after SCI and nerve transfer. Bcl-2 and Bax protein expression changes in the pontine micturition center were quantified by immunohistochemistry. The number of apoptotic neurons was determined by TUNEL staining. We examined pontine neuronal apoptosis by transmission electron microscopy (TEM) at different time points. RESULTS: H&E staining demonstrated that the number of neurons had increased in Group A, but more cells in Group B displayed nuclear pyknosis, with the disappearance of the nucleus. Compared with Group B, Group A had significantly higher Bcl-2 expression, significantly lower Bax expression, and a significantly higher Bcl-2/Bax ratio. The number of apoptotic neurons and neuron bodies in Group A was significantly lower than that in Group B, as indicated by TUNEL staining and TEM. CONCLUSIONS: These findings demonstrate that lumbosacral nerve transfer can reduce neuronal apoptosis in the pontine micturition center and enhance functional recovery of neurons. This result further suggests that lumbosacral nerve transfer can be used as a new approach for reconstructing bladder function after spinal cord injury.

Influence of Insurance Status on Curve Magnitude in Adolescent Idiopathic Scoliosis in Mainland China.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To determine whether there is an association between insurance status and curve magnitude in idiopathic scoliosis pediatric patients in mainland China. METHODS: Medical records of patients with adolescent idiopathic scoliosis in 4 tertiary spine centers across China from January 2013 to December 2017 were analyzed. Data was extracted on insurance status, curve magnitude, recommended treatment at presentation, source of referral, and treatment initiated. Additional information was collected for patients requiring corrective surgery, including time from recommendation for surgery to surgery and clinically relevant parameters such as, postoperative complications, and pre-/postoperative Scoliosis Research Society-22 scores were also collected for patients requiring corrective surgery. RESULTS: Of the 1785 patients included, 1032 were Urban Resident Basic Medical Insurance Scheme (URBMS) insured and 753 were New Rural Cooperative Medical Scheme (NRCMS) insured. NRCMS patients presented with a larger major curve than URBMS patients (32.9° ± 15.1° vs 29.3° ± 12.6°, P = .028). For patients having surgery recommended, NRCMS patients presented with a larger mean Cobb angle at the first presentation (57.7° vs 50.9°, P < .0001) and at time of surgery (61.3° vs 52.2°, P < .0001), and experienced a significantly longer time from surgery recommendation to decision for surgery. Complication rates were comparable between the 2 groups, except for pulmonary complications (NRCMS 7.3% vs URBMS 2.8%, P = .04). Postoperatively, patients covered by NRCMS insurance experienced greater overall improvement in health-related quality of life and were less satisfied with the treatments. CONCLUSIONS: This study shows that health insurance may influence the severity of scoliosis on presentation, with implications on early diagnosis and surgery time.

Transfer of Sciatic Nerve Motor Branches in High Femoral Nerve Injury: A Cadaver Feasibility Study and Clinical Case Report.

BACKGROUND: Femoral nerve injury causes knee dysfunction, and high femoral nerve injury is difficult to repair. OBJECTIVE: To evaluate the anatomic feasibility of transferring the sciatic nerve motor branches in high femoral nerve injury. METHODS: The femoral nerve was exposed in both lower extremities of 3 adult fresh-frozen cadavers; each branch was noninvasively dissected to its proximal nerve fiber intersection point and distal muscle entry point. The branches of the sciatic nerve were also exposed. The length, diameter, and number of myelinated fibers were measured in each femoral and sciatic nerve branch. The feasibility of tension-free direct suture between the femoral and sciatic nerve branches was evaluated. One patient was treated with transfer of a nerve branch innervating the semitendinosus muscle to the femoral nerve branch and was followed up for 18 mo. RESULTS: The diameters and numbers of myelinated fibers in the femoral nerve branches matched those of the sciatic nerve branches. In the single patient, a combined femoral nerve bundle (comprising the rectus femoris and vastus lateralis branches) was used as a graft. The branch of the sciatic nerve was sutured with the muscle branch of the femoral by using a sural nerve as a nerve graft. The knee joint straightening strength reached medical research council grade 4+. CONCLUSION: The proximal motor branches of the sciatic nerve may be transferred as donor nerves to repair high femoral nerve injury. A femoral nerve bundle comprising the rectus femoris and vastus lateralis branches may be used as the receptor nerve.

Translocation of the soleus muscular branch of the tibial nerve to repair high common peroneal nerve injury.

BACKGROUND: This study was performed to evaluate the clinical effect of translocating the soleus muscular branch of the tibial nerve to repair the deep peroneal nerve. METHODS: Eight patients were treated for high common peroneal nerve injury. The deep peroneal nerve was separated out from the common peroneal nerve if no injury occurred upon opening the epineurium of the common peroneal nerve. The soleus muscular branch of the tibial nerve was then translocated to the deep peroneal nerve. RESULTS: The average follow-up duration was 21.75 months. Electromyography revealed newly appearing electric potentials in the tibialis anterior, extensor hallucis longus, and extensor toe longus muscle at 8 to 10 months postoperatively. Four patients showed good functional recovery after surgery; functional recovery was poor in other patients. CONCLUSIONS: Translocation of the soleus muscle branch is a feasible method to treat high common peroneal nerve injuries. A full understanding of the indications for this operation is required.

A clinical comparison study of three different methods for treatment of transverse patellar fractures.

BACKGROUND: Tension bands structures are widely used to treat transverse patellar fractures. However, many implants-related complications have been reported. The purpose of this study is to evaluate effects and compare complications of three methods used to treat transverse patellar fractures, including titanium cable tension bands, compression screws with titanium cable cerclage, and X-shaped plating technique. METHODS: From January 2010 to March 2016, 120 cases of transverse patellar fracture received open reduction and internal fixation with one of three methods: titanium cable tension band (group A), compression screws with titanium cable cerclage (group B), and X-shaped plating technique (group C). Of these, 108 cases were followed for >2 years. Clinical and radiographic data were retrospectively collected and statistically compared. RESULTS: Final analysis included 108 patients (n = 38 in group A, 36 in B, and 34 in C). Reduction was satisfactory in all patients after surgery. No significant differences were noted in age, gender, time from injury to surgery, postoperative articular step-off, Lysholm score, and range of motion at 24 months among all groups. At final follow-up, 12 (31.6%) symptomatic implant complications were encountered in group A, along with 6 (16.7%) and 2 (5.9%) in groups B and C, respectively (p < 0.05). CONCLUSION: All three methods could achieve the goal of rigid fixation and early functional rehabilitation. However, the X-plate technique had the lowest risk of symptomatic implant complications and could thus be a safe and effective alternative for internal fixation of transverse patellar fractures.

Transferring of femoral nerve motor branches for high-level sciatic nerve injury: a cadaver feasibility study.

BACKGROUND: Sciatic nerve injuries cause significant disability. We propose here a novel reconstructive procedure of transferring the motor branches of the femoral nerve as donor nerves to reconstruct both the peroneal and tibial nerve function as a novel approach to treat high sciatic nerve injury. METHODS: The autopsies of donor nerves (vastus lateralis nerve branch (VLN), vastus medialis nerve branch (VMN), saphenous nerve (SAN)) and respective recipient nerves (deep peroneal nerve branch (DPN), medial gastrocnemius nerve branch (MGN), sural nerve (SN)) were conducted in six fresh-frozen lower limbs. The distance between the origin or bifurcation points of the nerves to the head of fibula and the diameter of the end at the coaptation site were measured. The feasibility of tensionless direct suturing or grafting between the donor nerves and the recipient was evaluated. Finally, the nerve end at the coaptation site was harvested for observation with toluidine blue staining and nerve fiber count. RESULTS: The mean diameter of the VMN, VLN, MGN, DPN, SAN, and SN nerves were 1.5 ± 0.1, 1.4 ± 0.1, 1.3 ± 0.1, 2.3 ± 0.1, 2.1 ± 0.3, and 1.3 ± 0.2 mm, respectively. Histological observation showed that the abovementioned six nerve bundles had a respective nerve fiber number of 392 ± 27, 205 ± 520, 219 ± 67, 394 ± 50, 308 ± 77, and 335 ± 49. A total of 5/6 specimens needed grafting for a length ranging from 5 to 15 cm to bridge the VMN-MGN, 6/6 needed a graft length of 10-20 cm for VLN-DPN bridging, and 2/6 needed a graft length of 0-4 cm for SAN-SN bridging. CONCLUSION: The study demonstrated the feasibility of the transferring femoral nerve branches to sciatic nerve branches to restore the function for sciatic injury.

A novel phytoextraction strategy based on harvesting the dead leaves: Cadmium distribution and chelator regulations among leaves of tall fescue.

The treatment of large amount of hazardous plant residues from phytoextraction is costly and has been a burden for the society. This experiment was designed to evaluate the possibility of cadmium (Cd) phytoextraction by harvesting the dead leaves instead of the whole plant in tall fescue (Festuca arundinacea). Results showed that Cd was preferentially distributed in the senescent and dead leaves. EDTA, DTPA and EGTA enhanced Cd accumulations in the dead leaves which could be associated to the increase of the water-soluble inorganic Cd and Cd-organic acid complexes in shoots. The dead leaves were only 12.6-16.3% of the total shoot biomass but accumulated 73.4-87.2% of the total shoot Cd. The results indicate that a novel strategy of Cd phytoextraction based on harvesting the dead leaves is feasible to save the high treatment cost of hazardous plant residues while maintaining the acceptable phytoextraction efficiency.

Transfer of obturator nerve for femoral nerve injury: an experiment study in rats.

BACKGROUND: Quadriceps palsy is mainly caused by proximal lesions in the femoral nerve. The obturator nerve has been previously used to repair the femoral nerve, although only a few reports have described the procedure, and the outcomes have varied. In the present study, we aimed to confirm the feasibility and effectiveness of this treatment in a rodent model using the randomized control method. METHODS: Sixty Sprague-Dawley rats were randomized into two groups: the experimental group, wherein rats underwent femoral neurectomy and obturator nerve transfer to the femoral nerve motor branch; and the control group, wherein rats underwent femoral neurectomy without nerve transfer. Functional outcomes were measured using the BBB score, muscle mass, and histological assessment. RESULTS: At 12 and 16 weeks postoperatively, the rats in the experimental group exhibited recovery to a stronger stretch force of the knee and higher BBB score, as compared to the control group (p < 0.05). The muscle mass and myofiber cross-sectional area of the quadriceps were heavier and larger than those in the control group (p < 0.05). A regenerated nerve with myelinated and unmyelinated fibers was observed in the experimental group. No significant differences were observed between groups at 8 weeks postoperatively (p > 0.05). CONCLUSIONS: Obturator nerve transfer for repairing femoral nerve injury was feasible and effective in a rat model, and can hence be considered as an option for the treatment of femoral nerve injury.

[Biomechanics test of fixation of star-shaped six-part patellar fractures with petal-shaped poly-axial locking plate].

Objective: To compare the biomechanical difference between petal-shaped poly-axial locking plate and tension band wire cerclage in fixing star-shaped 6-part patellar fractures in cadaver model, and provide the experimental data for clinical use. Methods: The paired 12 knee specimens from 6 human cadavers were randomly divided into 2 groups (the control group and the test group) after a star-shaped 6-part patellar fracture model was established. The specimens were weighted, and the control group was fixed with tension band wire cerclage and the test group was fixed with petal-shaped poly-axial locking plate. The specimens were connected to CMT5105 biomechanics test machine by a customized fixture, the total fracture gap of patellar fracture blocks was measured before testing. The knee extensor load test was performed to record the extensor load of knees at 90° flexion to extension. Then the anti gravity physiological knee extension process at 90° flexion was stimulated according to the knee extensor load. The cyclic times until failure and the total fracture gap of patellar fracture blocks after failure were recorded. Results: The specimens weight and the total fracture gap of patellar fracture blocks before testing between 2 groups had no significant difference ( t=0.410, P=0.690; t=0.650, P=0.530). In the biomechanical test, there was no significant difference of knee extension load between 2 groups ( t=0.490, P=0.638). The total fracture gap after failure in test group was significantly smaller than that in control group ( t=3.026, P=0.013), and the cyclic times until failure in test group was significantly more than that in control group ( t=2.277, P=0.046). The failure reasons in control group were all the wires slipped off the Kirschner wires, while the failure reasons in test group were the screws pulled out from the upper pole in 5 cases (83.3%) and from the lower pole in 1 case (16.7%). Conclusion: The petal-shaped poly-axial locking plate has better biomechanical stiffness to fix the star-shaped 6-part patellar fractures when compared with tension band wire cerclage method. However, this type of fracture is a serious comminuted type, and the early excessive activity still carries the risk of displacement.

[A finite element analysis of petal-shaped poly-axial locking plate fixation in treatment of Y-shaped patellar fracture].

Objective: To establish the finite element model of Y-shaped patellar fracture fixed with titanium-alloy petal-shaped poly-axial locking plate and to implement the finite element mechanical analysis. Methods: The three-dimensional model was created by software Mimics 19.0, Rhino 5.0, and 3-Matic 11.0. The finite element analysis was implemented by ANSYS Workbench 16.0 to calculate the Von-Mises stress and displacement. Before calculated, the upper and lower poles of the patella were constrained. The 2.0, 3.5, and 4.4 MPa compressive stresses were applied to the 1/3 patellofemoral joint surface of the lower, middle, and upper part of the patella respectively, and to simulated the force upon patella when knee flexion of 20, 45, and 90°. Results: The number of nodes and elements of the finite element model obtained was 456 839 and 245 449, respectively. The max value of Von-Mises stress of all the three conditions simulated was 151.48 MPa under condition simulating the knee flexion of 90°, which was lower than the yield strength value of the titanium-alloy and patella. The max total displacement value was 0.092 8 mm under condition simulating knee flexion of 45°, which was acceptable according to clinical criterion. The stress concentrated around the non-vertical fracture line and near the area where the screws were sparse. Conclusion: The titanium-alloy petal-shaped poly-axial locking plate have enough biomechanical stiffness to fix the Y-shaped patellar fracture, but the result need to be proved in future.