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Balancing the strength, ductility and Elastic modulus of β-Ti alloys is still a great challenge for medical implantation, extremely limiting its further applications. Herein, we prepared a fine-grain β-type Ti–24Nb–4Zr-2.5Mn alloy with high performance by adding CaB6 deoxidizer via mechanical alloying and spark plasma sintering. The effects of CaB6 addition on the microstructure and mechanical properties were systematically investigated, and the results show that adding a trace amount of CaB6 will form in-situ nano-sized CaTiO3 particles and micro-sized (Ti,Nb)B2 solid solution whiskers, which can significantly refine the grain size and inhibit the grain boundary movement and dislocation motion, thus improving the comprehensive mechanical properties of Ti–24Nb–4Zr-2.5Mn alloys. With a trace addition of 0.1 wt% CaB6, the Ti–24Nb–4Zr-2.5Mn alloy exhibits an excellent combination of high strength of ∼971 MPa, good ductility of ∼17.8% and low elastic modulus of ∼79.1 GPa. This work may provide a new methodology to prepare high-performance biomedical Ti alloys.

Purpose: To evaluate the efficacy of the endoscopic lumbar interbody fusion technique across different types of lumbar spondylolisthesis, specifically Grade I and Grade II, and suggest technical optimizations based on therapeutic outcomes, complications, and patient satisfaction for both grades. Methods: We analyzed data from 57 L4 to 5 spondylolisthesis patients, all categorized as either Grade I or Grade II, comprising 31 males and 26 females. Of these, 36 were diagnosed with Grade I and 21 with Grade II. All subjects underwent the endoscopic lumbar interbody fusion procedure. Primary evaluation metrics included pre and post-operative Vasual Analogue Scale（VAS） pain scores, Osewewtry Disability Index（ODI） functional scores, surgical duration, intraoperative blood loss, degree of spondylolisthesis correction, complications, and patient satisfaction levels. Results: At a minimum of 6 months post-operation, the VAS score for the Grade I cohort reduced from an initial 7.30 ± 0.69 to 2.97 ± 0.47, while the Grade II cohort saw a decrease from 7.53 ± 0.56 to 3.37 ± 0.62 (P = 0.0194). The ODI score in the Grade I group declined from 66.88 ± 5.15 % pre-operation to 29.88 ± 6.36 % post-operation, and in the Grade II group, it decreased from 69.33 ± 5.27 % to 34.66 ± 6.01 % (P = 0.0092). The average surgical duration for the Grade I group stood at 155.72 ± 17.75 min, compared to 180.38 ± 14.72 min for the Grade II group (P

The biomaterial requirements for bone tissue repair are extremely strict. It not only requires the biomaterial to have good biocompatibility and biological activity, but also requires sufficient mechanical strength. Polyamide 66 (PA66) and nano-hydroxyapatite (n-HA) have been widely investigated in bone tissue engineering scaffold, however, its composites require further research. In this study, the 3D printing technology was utilized to fabricate personalized n-HA/PA66 bone tissue scaffold. The mechanical properties of n-HA/PA66 composite can be adjusted by configuring different raw material components and applying different porosity. It was found that 50 % porosity n-HA/PA66 composite scaffold showed a uniform porous structure and a compressive strength of 33.9 MPa. The composite scaffold also exhibited excellent biological properties while improving mechanical properties, in vitro cell tests indicated that the 3D printed n-HA/PA66 composite scaffold promoted differentiation of bone marrow mesenchymal stem cells (BMSCs) into osteoblasts. In in vivo animal model proved that the scaffold promoted endogenous bone regeneration in rabbit patellar bone defects, with newly formed bone volume of 20.9 % after two months of implantation. This research proposed a 3D printed polyamide/nano-hydroxyapatite composite with balanced mechanical property and osteogenic ability for customized bone tissue repair, and it has promising application prospects.

Objective Although direct isthmic repair, such as PSVPH, did not affect the mobility of the fixed segment and adjacent segment, it has a relatively low rate of isthmic fusion compared with conventional fusion. The Isobar TTL dynamic internal fixation system has been widely used in clinical practice and has achieved satisfactory clinical results. However, the use of the Isobar TTL system in combination with direct isthmic repair for lumbar spondylolysis has rarely been reported. The aim of this study was to compare the clinical and radiologic outcomes between patients who underwent Isobar TTL system and PSVPH with direct repair of defect for lumbar spondylolysis. Methods Stepwise propensity score matching (PSM) for age and sex were performed to keep comparable clinical data between groups in this retrospective and matched‐pair case control study. A total of 50 patients diagnosed with lumbar spondylolysis underwent surgical implantation of the Isobar TTL group (n = 25) or PSVPH group (n = 25) from June 2009 to June 2016. Clinical outcomes were assessed using the Oswestry disability index (ODI), and visual analog score (VAS). Radiographic evaluations included range of motion (ROM) and the disc heights of stabilized segment and adjacent segment, adjacent segment degeneration (ASD) and bony fusion. Three‐dimensional reconstruction of lumbar CT scan was obtained to evaluate bone fusion of the isthmic at final follow‐up. The independent Student's t test and chi‐square test were applied to compare the differences between groups. Results A total of 25 patients from TTL group were matched to 25 patients in PSVPH group for age, sex, body mass index (BMI), defect side, spondylolisthesis meyerding, and follow‐up duration. The intervertebral space height (IH) of stabilized segment at postoperative 1 week and final follow‐up in the TTL group was higher than those in the PSVPH group, respectively (P = 0.030; P = 0.013). The ROM of stabilized segment at final follow‐up in the TTL group was significantly lower than that in the PSVPH group (P

The oxygen reduction reaction (ORR) electrocatalytic activity of Pt-based catalysts can be significantly improved by supporting Pt and its alloy nanoparticles (NPs) on a porous carbon support with large surface area. However, such catalysts are often obtained by constructing porous carbon support followed by depositing Pt and its alloy NPs inside the pores, in which the migration and agglomeration of Pt NPs are inevitable under harsh operating conditions owing to the relatively weak interaction between NPs and carbon support. Here we develop a facile electrospinning strategy to in-situ prepare small-sized PtZn NPs supported on porous nitrogen-doped carbon nanofibers. Electrochemical results demonstrate that the as-prepared PtZn alloy catalyst exhibits excellent initial ORR activity with a half-wave potential (E1/2) of 0.911 ​V versus reversible hydrogen electrode (vs. RHE) and enhanced durability with only decreasing 11 ​mV after 30,000 potential cycles, compared to a more significant drop of 24 ​mV in E1/2 of Pt/C catalysts (after 10,000 potential cycling). Such a desirable performance is ascribed to the created triple-phase reaction boundary assisted by the evaporation of Zn and strengthened interaction between nanoparticles and the carbon support, inhibiting the migration and aggregation of NPs during the ORR.

Purpose Treatment of adjacent segment disease (ASD) is still controversial. The aim of this study was to evaluate the short‐term efficacy and safety and to analyze the technical advantages, surgical approach, and indications of percutaneous full endoscopic lumbar discectomy (PELD) in the treatment of ASD after lumbar fusion in elderly patients. Methods A retrospective of 32 patients with symptomatic ASD were accepted for PELD from October 2017 to January 2020. All patients used the transforaminal approach and recorded the operation time and intraoperative conditions. Preoperative, 3, 12, 24 months of postoperative and at the last follow‐up, the pain of back and leg of visual analog scale (VAS), Oswestry dysfunction index (ODI), and Japanese Orthopaedic Association Assessment Treatment Score (JOA) were performed, and the paired student's t test was used to the compare the continuous variables preoperatively and postoperatively. The clinical efficacy was evaluated according to MacNab standards. The lumbar MRI was performed to evaluate the decompression of the nerve roots, and the lumbar lateral and dynamic X‐rays were performed to evaluate the stability of the surgical segment. Results A total of 32 patients were included in the study, including 17 males and 15 females. The follow‐up time ranged from 24 to 50 months, with an average of (33.2 ± 8.1) months and an average operation time of (62.7 ± 28.1) minutes. Compared to preoperatively, the VAS score of the back and leg pain (p

Development of wound dressings with antimicrobial activity and promotion of sustained wound healing to reduce the use of antibiotics in infected wounds is important. In this study, we developed a thermosensitive ABA triblock copolymer poly {(N-isopropyl acrylamide)–co-[(6-((3-(6-amino-purin-9-yl)propanoyl)oxy)hexyl acrylates)]-b-PEO-b-Poly (N-isopropyl acrylamide)–co-{[(6-((3-(6-amino-purin-9-yl)propanoyl)oxy)hexyl acrylates)]} as matrix and participating nitric oxide (NO) donor (N,N'-dis-sec-butyl-N,N'-dinitroso-1,4-phenylenediamine, BNN6) loaded SiO2@PDA nanoparticles composed of hydrogel dressings (Gel-APB) for efficient antimicrobial and sustainable treatment of wounds. Thanks to the presence of poly (N-isopropyl acrylamide) (PNIPAM) and unique ABA triblock structure, the NAONA copolymer would self-assemble into temperature-sensitive injectable hydrogel with excellent dermal adaptation to dynamic wounds. Meanwhile, the biobase adenine endowed the hydrogel dressing with self-healing ability. Under 808 nm wavelength irradiation, the hydrogel was able to elevate to a mild temperature (∼48 °C) and release NO on demand, which efficiently kills E. coli and S. aureus, realizing highly efficient and mild photothermal antimicrobial therapy (PTAT). In addition, full-thickness skin wound modeling demonstrated that Gel-APB hydrogel dressing accelerated tissue regeneration, angiogenesis, and collagen deposition in S. aureus infected wounds in vivo, achieving rapid wound healing. Thus, Gel-APB is a multifunctional hydrogel dressing with excellent antimicrobial activity and has considerable potential for application in infected skin wound healing.

Intervertebral disc degeneration (IDD) is the main cause of low back pain (LBP), which significantly impacts global wellbeing and contributes to global productivity declines. Conventional treatment approaches, encompassing conservative and surgical interventions, merely serve to postpone the advancement of IDD without offering a fundamental reversal. Consequently, there is an urgent demand for an effective approach to prevent the progression of IDD. Recent investigations focusing on the treatment of IDD utilizing diverse bioactive substances integrated within various biomaterials have exhibited promising outcomes. Various bioactive substances, encompassing conventional small molecule drugs, small molecule nucleic acids, and cell therapies, exhibit distinct capacities for repairing IDD. Additionally, various biological material delivery systems, such as nano micelles, microspheres, and hydrogels, possess diverse biological and release characteristics. Consequently, these diverse materials and drugs hold promise for advancing the treatment of IDD. This article aims to provide a concise overview of the IDD process and investigate the research advancements in biomaterials and bioactive substances for IDD treatment, delving into their mechanisms.

Chronic diabetic wounds seriously threaten human health due to their intractable nature in a complex pathological microenvironment that contains oxidative stress, persistent inflammatory status, hypoxia and bacterial infections, of which oxidative damage contributing the most. Applied materials that can mimic the natural intracellular antioxidant defense system are perceived to have huge therapeutic potential. Herein, we present a novel strategy to prepare a versatile nanocomposite hydrogel by incorporating the nanoenzyme (manganese dioxide (MnO2)) and nonenzymatic antioxidant components (polydopamine (PDA)) in a dynamic hydrogel network composed of thioctic acid and tannic acid (TA). The prepared hydrogel exhibited outstanding adhesive and injectable properties, making it adapt perfectly to wounds with different shapes and depths. More importantly, encapsulation of PDA@MnO2 nanoparticles (NPs) conferred the hydrogel with superior antioxidant performance to effectively scavenge multiple types of reactive nitrogen and oxygen species (RNOS) and reduce the inflammatory response by regulating macrophage polarization. Meanwhile, the hydrogel showed high-performance catalyzing ability to transfer hydrogen peroxide (H2O2) into oxygen (O2), which could further alleviate hypoxic wound environment. Moreover, the nanocomposite hydrogel exhibited excellent near-infrared (NIR) photothermal antibacterial effect. Collectively, our findings indicate that the synthesized nanocomposite hydrogel shows potential for use in a clinical setting to treat diabetic wounds.

Water pollution is an increasingly serious environmental problem because many pollutants have carcinogenic effects on humans and aquatic organisms. Metal organic framework (MOF), made up of metal ions and multifunctional organic ligands, has been one of the most concerned materials because of its adjustable and regular pore structure. MOFs have always shown attractive advantages in membrane separation and adsorption technologies, among which water-stable MOFs are particularly prominent in wastewater treatment (WWT) applications. This review systematically summarizes the application of MOF membranes in membrane filtration, membrane pervaporation and membrane distillation. Also, the adsorption mechanisms of heavy metals, dyes and antibacterials in wastewater have been concluded. In order to tap the full application potential of pristine MOFs in sustainable wastewater treatment, current challenges are discussed in detail and future research directions are proposed.

In the present work, the microstructure evolution, mechanical and corrosion properties of Fe–13Cr–4Al-1.5Nb alloys were systematically studied after the long-term thermal aging treatment. After aging, the Fe–13Cr–4Al-1.5Nb alloys are still mainly composed of α-Fe phase and a small amount of Fe2Nb-type laves phase, but the preferred orientation almost disappeared. With the increase of aging time, the average grain size of Fe–13Cr–4Al-1.5Nb alloy increased obviously and the amount of Fe2Nb-type laves phase also increased significantly. After aging at 450 °C for 2000 h, some coarse grains were observed in the Fe–13Cr–4Al-1.5Nb alloy and it exhibited much coarser grains with an average grain size of 19.7 μm than unaged Fe–13Cr–4Al-1.5Nb alloy due to the incomplete recrystallization. With the increase of aging time, the tensile strength was almost unchanged while the ductility decreased significantly. Due to the incomplete recrystallization, the Fe–13Cr–4Al-1.5Nb alloy exhibited the highest tensile strength of 670.5 MPa but the worst elongation of 3.9% after aging at 450 °C for 2000 h. In addition, the electrochemical corrosion test results showed that the unaged Fe–13Cr–4Al-1.5Nb alloy has better comprehensive corrosion resistance than the aged Fe–13Cr–4Al-1.5Nb alloy in 3.5wt.%NaCl solution.

Low back pain caused by disc herniation and spinal stenosis imposes an enormous medical burden on society due to its high prevalence and refractory nature. This is mainly due to the long-term inflammation and degradation of the extracellular matrix in the process of intervertebral disc degeneration (IVDD), which manifests as loss of water in the nucleus pulposus (NP) and the formation of fibrous disc fissures. Biomaterial repair strategies involving hydrogels play an important role in the treatment of intervertebral disc degeneration. Excellent biocompatibility, tunable mechanical properties, easy modification, injectability, and the ability to encapsulate drugs, cells, genes, etc. make hydrogels good candidates as scaffolds and cell/drug carriers for treating NP degeneration and other aspects of IVDD. This review first briefly describes the anatomy, pathology, and current treatments of IVDD, and then introduces different types of hydrogels and addresses “smart hydrogels”. Finally, we discuss the feasibility and prospects of using hydrogels to treat IVDD.

Abstract Purpose To explore the clinical efficacy and operation points of cervical radiculopathy with osseous foraminal stenosis treated with ultrasonic osteotome in anterior cervical surgery. Methods From January 2018 to June 2021，a retrospective analysis of 23 patients with cervical radiculopathy with bony foraminal stenosis during this period was retrospectively analyzed. Anterior Cervical Discectomy and Fusion (ACDF) was used for all cases in this group. Intraoperative use of ultrasonic osteotome to decompress the nerve in the intervertebral foramina. The operation time, intraoperative blood loss and complication rate were recorded in this group of patients. Interbody fusion was evaluated using Brantigan criteria. The IC-PACS imaging system was used to measure the intervertebral foramen area (IFA) before and after surgery to evaluate the range of decompression. The VAS (Visual Analogue Scale, VAS) score and NDI (Neck Disability Index, NDI) score before and after surgery were recorded to evaluate the clinical efficacy. Results All enrolled patients were followed up regularly for 1 year or more. The mean operative time was 61.5 ± 8.0 minutes. The average intraoperative blood loss was 88.3 ± 12.8 ml, and the average hospital stay was 8.1 ± 1.7d. Twenty one cases of successful fusion were followed up 1 year after operation, and the fusion rate was 91.3%. IFA expanded from 25.1 ± 4.0 mm2 before operation to 57.9 ± 3.4 mm2 at 1 year after operation, and the difference was statistically significant (P

Abstract Proton exchange membrane fuel cells (PEMFCs) have become a major component of current clean energy technologies. Accounting for nearly half the cost of a commercial fuel cell stack, Pt‐based catalysts are the main choices for both anode and cathode in PEMFCs. However, catalytical activity and operating life of Pt‐based catalysts are still unsatisfactory. High cost and scarcity of Pt further hinder the development of PEMFCs. Constructing core‐shell structure for Pt‐based catalysts is a promising strategy to enhance the catalytic activity and reduce the cost. In this review, we overview recent advances in Pt‐based core‐shell catalysts according to catalytic reaction types involved in PEMFCs. Furthermore, we discuss the working principle of core‐shell catalysts from the perspective of coupling between core and shell. In the end, we conclude the recent progress and discuss the future developments and facing challenges.

BackgroundDue to the low incidence of adult fibrosarcoma (AFS), it is difficult for clinicians to assess cancer-specific survival (CSS) in elderly patients based on this study. The study aimed to develop nomograms capable of accurately predicting 3-, 5-, and 8-year CSS in patients over 40 years of age with AFS.MethodsData were collected from The Surveillance, Epidemiology, and End Results (SEER) registry. 586 patients were included in this study. Univariate as well as multivariate Cox regression analyses were applied to identify independent risk factors. A nomogram was constructed and validated to predict the 3-, 5-, and 8-year CSS of patients.ResultsFive variables including age, sex, stage, grade, and chemotherapy status were considered independent risk factors and were used to construct the nomogram. The nomogram was well validated. The C-indexes of the training cohort and the validation cohort are 0.766 and 0.780, respectively. In addition, the area under the curves for 3-, 5- and 8-year CSS are 0.824, 0.846 and 0.840 in the training cohort, 0.835, 0.806 and 0.829 in the validation cohort. Calibration curves were also plotted to show that predicted endings have a well fit for the true endings. Finally, decision curve analysis demonstrates that the nomogram can bring a high benefit to patients.ConclusionWe successfully constructed a highly accurate nomogram to predict the CSS of AFS patients at 3-, 5-, and 8 years. The nomogram can greatly help clinicians and patients with AFS.

Abstract Hydroxyapatite (HA) bioceramics have been extensively employed as bone tissue scaffolds owing to their biodegradability and osteoinductivity. In our work, HA, a significant component of natural bone tissue used as the raw material to produce porous scaffolds employing three‐dimensional (3D)‐printing technology. Physical and chemical properties, porosity, and compression resistance of the scaffolds were investigated in vitro. The scaffold was confirmed to have a large number of interconnected pore structures on the surface and inside HA scaffolds showed good cell compatibility and cell adhesion in cell text. To analyze the effect of the scaffold on bone repair and regeneration in vivo, the large‐size defect of beagle skull was repaired with a 3D printing group and an autologous bone group (ABG) for 8 months. Images and histological analysis of the 3D printing group indicated better integration with adjacent tissues. However, there were obvious gaps in the ABG, which indicates weak bone regeneration ability of this group due to unmatched implant dimension. Immunohistochemistry and immunofluorescence results showed that 3D‐printed scaffolds had a highly vascularized structure. This study indicates that 3D‐printed bioceramics scaffolds that are osteoinductivity and biodegradable have great potential in maxillofacial bone regeneration.

Abstract Electrochemical nitrate (NO3−) reduction is a green and economic route for ammonia (NH3) synthesis. However, this conversion suffers from low NH3 selectivity due to strong competition from other NO3− reduction pathways. Here, we report that a plasma‐induced defective CoTiO3 − x nanofiber with oxygen vacancies acts as an efficient electrocatalyst for NO3− reduction to NH3. In 0.1 M NaOH solution containing 0.1 M NO3−, it is capable of achieving a remarkable NH3 yield of 30.4 mg h–1 mgcat.–1 and a high Faradaic efficiency of 92.6%. The catalyst also shows strong electrochemical stability for a 20‐h electrolysis test. Additionally, a Zn‐NO3− battery using CoTiO3 − x as the cathode catalyst offers a peak power density of 5.04 mW cm−2 and a large NH3 yield of 3.08 mg h−1 mgcat.−1. The catalytic mechanism is further discussed by density functional theory calculations.

Abstract Background The high postoperative recurrence rate and refractoriness of relapsed tumors are still a conundrum for the clinical management of osteosarcoma (OS). New therapeutic options are urgently needed. Depriving the nourishment of myeloid-derived suppressor cells is a novel strategy to improve the immunosuppressive tumor microenvironment for enhanced OS therapy. Methods We synthesized a hyaluronic acid (HA)-modified metal–organic framework for combinational chemotherapy and immunotherapy of OS. Zeolitic Imidazolate Framework-8 (ZIF-8) was prepared by a one-pot synthetic method, Gemcitabine (Gem) and D-1-Methyltryptophan (D-1-MT) were loaded into the ZIF-8 during the synthesis process to make ZIF-8@Gem/D-1-MT nanoparticles (NPs). The end product (HA/ZIF-8@Gem/D-1-MT NPs) was obtained by HA modification on the surface of ZIF-8@Gem/D-1-MT NPs. The obtained HA/ZIF-8@Gem/D-1-MT NPs have excellent potential as a drug delivery vector for chemotherapy and immunotherapy in vitro and vivo. Results The results indicate that HA/ZIF-8@Gem/D-1-MT NPs were readily taken up by OS cells, and that the Gem and D-1-MT were effectively released into the acidic environment. The HA/ZIF-8@Gem/D-1-MT NPs could efficiently decrease OS cell viability (proliferation, apoptosis, cell cycle, migration and invasion). And HA/ZIF-8@Gem/D-1-MT NPs could reactivate antitumor immunity by inhibiting indoleamine 2,3 dioxygenase and myeloid-derived suppressor cells. Furthermore, animal experiments confirmed that HA/ZIF-8@Gem/D-1-MT NPs could induce intratumoral immune responses and inhibit tumor growth. Additionally, HA/ZIF-8@Gem/D-1-MT NPs have a good safety profile. Conclusions Our findings demonstrate that the combination of Gem with D-1-MT brings new hope for the improved treatment of OS, while the generation of the nanosystem has increased the application potential and flexibility of this strategy.

Abstract Because of features, such as adjustable structures, high porosity, and high crystallinity, metal–organic frameworks (MOFs) deservedly have received considerable attention. Nevertheless, there is still room for improvements in the electrical conductivity and chemical stability of some MOFs, because of which they cannot be utilized as electrode materials. Fortunately, MOF derivatives have received widespread attention in recent years, especially phosphide materials, which are widely used in practical applications because of their outstanding conductivity, excellent specific surface area, and standout charge mobility. In this review, the latest developments of MOF‐derived phosphides in electrocatalysis related to energy, including the excellent performance in terms of electrochemical energy storage and ingenious strategies, and diversified synthetic approaches have been emphasized and summarized. Additionally, the arduous task and feasible proposals of MOF‐derived phosphides are also discussed.

Abstract Limited lithium resources have promoted the exploration of new battery technologies. Among them, potassium‐ion batteries are considered as promising alternatives. At present, commercial graphite and other carbon‐based materials have shown good prospects as anodes for potassium‐ion batteries. However, the volume expansion and structural collapse caused by periodic K+ insertion/extraction have severely restricted further development and application of potassium‐ion batteries. A hollow biomass carbon ball (NOP‐PB) ternarily doped with N, O, and P was synthesized and used as the negative electrode of a potassium‐ion battery. X‐ray photoelectron spectroscopy, Fourier‐transform infrared spectroscopy, and transmission electron microscopy confirmed that the hollow biomass carbon spheres were successfully doped with N, O, and P. Further analysis proved that N, O, and P ternary doping expands the interlayer distance of the graphite surface and introduces more defect sites. DFT calculations simultaneously proved that the K adsorption energy of the doped structure is greatly improved. The solid hollow hierarchical porous structure buffers the volume expansion of the potassium insertion process, maintains the original structure after a long cycle and promotes the transfer of potassium ions and electrons. Therefore, the NOP‐PB negative electrode shows extremely enhanced electrochemical performance, including high specific capacity, excellent long‐term stability, and good rate stability.

Promoting refractory wound healing remains a challenging issue. Currently, dressings with intelligent infection management functions built on infection eradication and reactive oxygen species (ROS) scavenging abilities are lacking. In this study, an approach based on Cu2+-imidazole coordination cross-linked histidine grafted chitosan (CS-His) and carbon quantum dots (CQDs) was developed to engineer superoxide dismutase (SOD) mimicking centers with photothermal anti-infection and intelligent anti-infection abilities, beyond typical ROS scavenging activity. The cross-linked coordination network was further promoted with tanshinol-encapsulated ZIF-8 frameworks (ZIF-8@Ts) to achieve intelligent infection management behaviors. These designs generate a refractory wound-healing hydrogel with integrated functions of photothermal anti-infection, SOD mimicking activity, and intelligent infection management. In response to infection exacerbation, the SOD mimicking centers and ZIF-8@Ts nanoparticles could release CQDs for anti-infection and Ts for antioxidation, respectively. In vitro results revealed photothermal anti-infection, ROS scavenging, and intelligent infection management capacities of the hydrogel. These abilities promoted the M2 transformation of macrophages and rescued the inhibitory effect of infection on fibroblast proliferation and migration. The hydrogel exhibited high regenerative efficacy in a rat model of chronically infected diabetic wounds. These results demonstrated the immense potential of the intelligent hydrogel integrated with multifunctions for refractory wound healing.

BackgroundAs a rare tumor, surgery is the best treatment for primary spinal tumors. However, for elderly patients who cannot undergo surgery, the prognosis is often difficult to evaluate. The purpose of this study was to identify the risk factors that may lead to death and predict the prognosis of elderly patients with primary spinal tumors who have not undergone surgical treatment. MethodsIn this study, 426 patients aged 60 years or older diagnosed with a primary spinal tumor between 1975 and 2015 were selected and included from the Surveillance, Epidemiology, and End Results database. A retrospective analysis was performed by using the Cox regression algorithm to identify independent prognostic factors. A nomogram model was developed based on the results. Multiple evaluation methods (calibration curve, receiver operating characteristic curve, and decision curve analyses) were used to evaluate and validate the performance of the nomogram.ResultsA nomogram was developed, with age, histological type, and stage as independent prognostic factors. The results indicated that the prognostic risk tended to increase significantly with age and tumor spread. Osteosarcoma was found to have the most prominent risk prognosis in this patient group, followed by chondrosarcoma and chordoma. The area under the curve and the C-index of the model were both close to or greater than 0.7, which proved the high-differentiation ability of the model. The calibration curve and decision curve analyses showed that the model had high predictive accuracy and application value.ConclusionsWe successfully established a practical nomogram to assess the prognosis of elderly patients with primary spinal tumors who have not undergone surgical treatment, providing a scientific basis for clinical management.

ObjectiveTo explore the clinical effect and operating skills of channel assisted Cervical Key Hole technology combined with Ultrasonic Bone Osteotome (CKH-UBO) in the treatment of single segment cervical spondylotic radiculopathy (CSR).MethodsFrom June 2018 to June 2020, 14 patients diagnosed with CSR and treated with channel assisted CKH-UBO were collected. The duration of the disease, the length of the incision, the operation time, the amount of bleeding during the operation, the length of hospitalization and the complications were recorded. The Range Of Motion (ROM) and the stability of the surgical segment were recorded before and after the operation. Visual analog scale (VAS), neck disability index (NDI) and modified macnab efficacy evaluation criteria were used to evaluate the surgical efficacy.ResultsThe operative segments of the enrolled patients were all lower cervical vertebrae. The average incision length was 2.0 ± 0.1 cm, the operation time was 42.2 ± 5.7 min, the intraoperative bleeding volume was 32.7 ± 4.1 ml, and the hospital stay was 5.6 ± 1.2 days. There was no difference in ROM between preoperative and 3 months and 1 year after operation (P > 0.05), and all patients did not have segmental instability. The VAS scores of neck pain before surgery, 3 days after surgery, 3 months after surgery, and 1 year after surgery were 5.6 ± 1.2, 1.6 ± 0.6, 1.1 ± 0.7, 0.6 ± 0.5, and the VAS scores of upper limb pain were 6.2 ± 1.2, 1.7 ± 0.7, 1.1 ± 0.6, 0.6 ± 0.5. The NDI scores of upper limb pain before surgery, 3 days after surgery, 3 months after surgery, and 1 year after surgery were 36.7 ± 3.5, 9.8 ± 2.4, and 3.9 ± 1.5, 1.8 ± 1.0, The VAS and NDI scores at all follow-up time points after operation were significantly lower than those before operation (P

ObjectiveTo investigate the clinical efficacy and technical points of Percutaneous Coaxial Large-channel Endoscopic Lumbar Interbody Fusion (PCLE-LIF) in the treatment of degenerative lumbar spinal stenosis.MethodsThe clinical data of patients with single-segment degenerative lumbar spinal stenosis who underwent PCLE-LIF surgery from January 2019 to June 2021 were retrospectively analyzed. Surgery-related data included symptom duration, operation time, hospital stay, and complication rate. Functional score data included low back pain and lower extremity pain VAS score, ODI score, and MacNab criteria were used to evaluate clinical effects. The Brantigan criteria were used to evaluate the interbody fusion.ResultsThere were 62 patients in this group, including 35 males and 27 females. The surgical sites were all lower lumbar spine, including 35 cases of lumbar L4/5 and 27 cases of L5/S1. The length of hospital stay was 7.7 ± 1.4 days. All patients were followed up regularly for 1 year. The interbody fusion rate was 93.5% at 1 year after operation. There were 2 cases of numbness, 2 cases of nerve edema and pain, 1 case of cage displacement, and 1 case of pedicle screw loosening. The complication rate was 9.6%. The VAS scores of low back pain 1 day before surgery, 3 days, 3 months and 1 year after surgery were 4.48 ± 1.06, 0.84 ± 0.81, 0.40 ± 0.56, 0.39 ± 0.69, and the VAS of lower extremity pain at each time point of appeal were 5.58 ± 0.98, 0.91 ± 0.58, 0.31 ± 0.46, 0.19 ± 0.40. The ODI scores at 1 day before surgery, 3 months and 1 year after surgery were 60.01 ± 6.21, 15.58 ± 2.84, 8.82 ± 2.15. The ODI scores and VAS scores of low back pain and lower extremity pain at each follow-up time point after operation were significantly lower than those before operation (p

Treatment of large-scale bone defects remains a clinical challenge. In particular, it preferably requires an implantable material with porous, absorbable, biocompatible, and antibacterial activities. Here we report the mechanical and biological properties of a porous Zn–0.04Mg–2Ag (wt%) biodegradable zinc alloy scaffold, prepared by template replication technique. In the aspect of cytocompatibility, cytoskeleton staining of stem cells co-cultured with Zn–0.04Mg–2Ag showed that the outline of cells and nuclei was clearly visible, and the interwoven network of linear fibers was abundant in the cells, which revealed lower cytotoxicity and less effect on cell proliferation. In the aspect of antibacterial properties, Zn–0.04Mg–2Ag alloy had little antibacterial effect on Escherichia coli, but had obvious antibacterial ability against Staphylococcus aureus and Staphylococcus epidermidis. In the aspect of bone induction, alizarin red staining and the expression of alkaline phosphatase showed no obvious increase; However, Zn–0.04Mg–2Ag alloy could significantly up-regulate the mRNA expression of osteoblast-specific transcription factors, osteocalcin and osteopontin. Zn–0.04Mg–2Ag degradable zinc alloy scaffold had excellent biocompatibility, and has significant antibacterial activity and fine osteogenic induction, which was an ideal bone substitute material for repairing large-scale bone defects.

In nature, many natural porous tissues of animals or plants follow heterogeneous structures pattern. Including turtle back pattern, leaf veins, wood porous fiber and porous cancellous bone are classic heterogeneous structures. In order to better design bionic microenvironment porous bone implants, herein, a bionic porous structure based on Voronoi-Thiessen diagram to create heterogeneous topology microenvironment promoting bone regeneration were proposed. Porous structures with tunable heterogeneity were built and achieved by selective laser melting (SLM). The topology analysis revealed the introduce of heterogeneity brought wide pore size distribution and irregular topology. The mechanical and hydrodynamics properties were predesigned and simulated by finite element analysis (FEA). The heterogeneity hardly influenced the overall strength, stiffness and permeability but the irregular stress and fluid shear rate distribution in FEA results indicated fluctuating local stiffness and permeability. In vitro and in vivo experimental results indicated that Quasi-homogeneous structure had irregular topology mimicking that of the natural bone structure and semi-heterogenous structure shown better osteogenesis. It is found that the scaffold heterogeneous microenvironment factors play important roles for bone regeneration, and which is crucial for the development of new orthopedic implants.

Promoting refractory wound healing remains a major therapeutic challenge. Here, a pain reflex-inspired hydrogel responsive to inflammatory microenvironmental conditions was developed and used to treat chronically infected diabetic wounds. This material was produced by reacting ε-Polylysine, which exhibits antibacterial properties, with oxidized hyaluronic acid to yield a dynamic Schiff base-crosslinked hydrogel capable of undergoing triggered dissociation in response to the lower microenvironmental pH found within refractory wounds. This hydrogel exhibited intrinsic antimicrobial activity owing to the incorporation of ε-Polylysine within the hydrogel network. To imbue the hydrogel with low pH-inducible anti-inflammatory and angiogenic activity, Schiff base bonds were used to capture Deferoxamine (DFO)-loaded amino-functionalized mesoporous silica nanoparticles (MSNs-NH2@DFO) on this hydrogel skeleton. The reflexive behaviors of the hydrogel make it ideally suited to facilitating wound healing in response to excessive local inflammation. The resultant intelligent hydrogel was highly biocompatible and exhibited robust antibacterial, anti-inflammatory, and pro-angiogenic activity in vitro and in vivo, thus effectively promoting the healing of chronically infected diabetic wounds. This novel hydrogel therefore holds great promise as a tool to promote refractory wound healing.

Abstract Purpose This prospective cohort study reports on a modified technique, namely precise safety decompression via double percutaneous lumbar foraminoplasty (DPLF) and percutaneous endoscopic lumbar decompression (PELD) for lateral lumbar spinal canal (LLSC) stenosis, and its short-term clinical outcomes. Methods The study analyzed 69 patients with single-level LLSC stenosis simultaneously occurring in both zones 1 and 2 (defined as retrodiscal space and upper bony lateral recess respectively by new LLSC classification) who underwent DPLF–PELD from November 2018 to April 2019. Clinical outcomes were evaluated according to preoperative, 3 months postoperatively, and last follow-up, via leg pain/low back pain (LBP) visual analog scale (VAS) scores, Oswestry disability index (ODI) scores, and the Macnab criteria. The postoperative MRI and CT were used to confirm the complete decompression, and flexion-extension x-rays at the last follow-up were used to observe lumbar stability. Results All patients successfully underwent DPLF–PELD, and the stenosis was completely decompressed, confirmed by postoperative MRI and CT. The mean follow-up duration was 13 months (range: 8–17 months). The mean preoperative leg pain VAS score is 7.05 ± 1.04 (range 5–9), which decreased to 1.03 ± 0.79(range: 0–3) at 3 months postoperatively and to 0.75 ± 0.63 (range: 0–2) by the last follow-up visit (p

Abstract Background At present, few reports of percutaneous endoscopic transforaminal decompression surgery have been reported to solve central lumbar spinal stenosis (CLSS). Is endoscopic decompression through bilateral transforaminal approach decompression sufficient for degenerative CLSS? Methods This retrospective study included 47 cases of CLSS patients who underwent percutaneous endoscopic decompression through bilateral transforaminal approach. Clinical outcomes such as ODI, back and leg VAS, the Macnab criteria were evaluated. Surgical results including operative time, postoperative hospital stay, recurrence, and surgical complications were also studied. Radiologically, lumbar stability was assessed and lumbar dural sac dimension was compared preoperatively and postoperatively. Results All 47 patients were followed up. The average follow-up period was 24.5 months. The average operation time was 116 min. The mean VAS of leg and back pain, and the mean ODI improved from 7.81, 2.53, and 77.03% at baseline to a final 1.94 (P = 0.00), 2.47 (P = 0.71), and 19.40% (P = 0.00), respectively. According to the Macnab criteria, 97.9% of patients achieved excellent and good results. There were 2 cases of dural tear and 3 cases of transient postoperative dysthesia. The cross-sectional area of the dural sac was significant enlargement at the last fellow up (74.28 ± 13.08 mm2 vs.104.91 ± 12.40 mm2, P = 0.00). Conclusions Except for the main pathogenic factors on the dorsal side of the dural sac, percutaneous endoscopic decompression through a bilateral transforaminal approach is sufficient for CLSS. It is a feasible, safe, and clinically effective minimally invasive procedure.

Abstract Artificial Z‐scheme, a tandem structure with two‐step excitation process, has gained significant attention in energy production and environmental remediation. By effectively connecting and matching the band‐gaps of two different photosystems, it is significant to utilize more photons for excellent photoactivity. Herein, a novel one‐photon (same energy‐two‐photon) Z‐scheme system is constructed between rGO modified boron‐nitrogen co‐doped‐WO3, and coupled CdSe quantum dots‐(QDs). The coctalyst‐0.5%RhxCr2O3(0.5RCr) modified amount‐optimized sample 6%CdSe/1%rGO3%BN‐WO3 revealed an unprecedented visible‐light driven overall‐water‐splitting to produce ≈51 µmol h−1 g−1 H2 and 25.5 µmol h−1 g−1 O2, and it remained unchanged for 5 runs in 30 h. This superior performance is ascribed to the one‐photon Z‐scheme, which simultaneously stimulates a two photocatalysts system, and enhanced charge separation as revealed by various spectroscopy techniques. The density‐functional theory is further utilized to understand the origin of this performance enhancement. This work provides a feasible strategy for constructing an efficient one‐photon Z‐scheme for practical applications.

Osteoporosis is mainly a geriatric disease with a high incidence, and the resulting spinal fractures and hip fractures cause great harm to patients. Anti-osteoporosis drugs are the main treatment for osteoporosis currently, but these drugs have potential clinical limitations and side effects, so the development of new therapies is of great significance to patients with osteoporosis. Electrical stimulation therapy mainly includes pulsed electromagnetic fields (PEMF), direct current (DC), and capacitive coupling (CC). Meanwhile, electrical stimulation therapy is clinically convenient without side effects. In recent years, many researchers have explored the use of electrical stimulation therapy for osteoporosis. Based on this, the role of electrical stimulation therapy in osteoporosis was summarized. In the future, electrical stimulation might become a new treatment for osteoporosis.

Osteoporosis, a systemic bone disease, is characterized by decreased bone density due to various reasons, destructed bone microstructure, and increased bone fragility. The incidence of osteoporosis is very high among the elderly, and patients with osteoporosis are prone to suffer from spine fractures and hip fractures, which cause great harm to patients. Meanwhile, osteoporosis is mainly treated with anti-osteoporosis drugs that have side effects. Therefore, the development of new treatment modalities has a significant clinical impact. Sympathetic nerves play an important role in various physiological activities and the regulation of osteoporosis as well. Therefore, the role of sympathetic nerves in osteoporosis was reviewed, aiming to provide information for future targeting of sympathetic nerves in osteoporosis.

High-performance low-cost catalysts are in high demand for the hydrogen evolution reaction (HER). In the present study, we reported that V1.11S2 materials with flower-like, flake-like, and porous morphologies were successfully synthesized by hydrothermal synthesis and subsequent calcination. The effects of morphology on hydrogen evolution performance were studied. Results show that flower-like V1.11S2 exhibits the best electrocatalytic activity for HER, achieving both high activity and preferable stability in 0.5 M H2SO4 solution. The main reason can be ascribed to the abundance of catalytically active sites and low charge transfer resistance.

Jaw bone repair requires scaffold with bone regeneration, antibacterial function and personalized size. This study proposed 3D printed degradable calcium phosphate scaffolds with antibacterial functions for regeneration of jaw bone. Calcium phosphate powders and berberine were combined to modulate the printing inks. Porous scaffolds were fabricated by direct extrusion 3D printing and cross-linked with sodium alginate in situ. The dimensional size, shape and porosity of scaffolds were precisely customized by 3D printing. Berberine-loaded scaffolds show sustained release of antimicrobial drugs. By adjusting the concentration and cross-linking time of calcium chloride, the cross-linking degree of the scaffold can be adjusted and the drug load of the scaffold can be controlled. The young's modulus of 3DP scaffold was about 1.3 MPa. After freeze-drying, the shrinkage was about 24.4% and less swelling was observed, indicating that the scaffold had sufficient structural stability. In vitro biological test showed that the 3DP scaffold had low cytotoxicity and it was beneficial to MC3T3 cell adhesion and proliferation. 3D printed calcium phosphate scaffolds with controlled-release antibacterial properties is a promising biomaterials for jaw repair. Keywords: 3D printing, Bone tissue engineering, Calcium phosphate, scaffolds, Antibacterial functions

Through computational calculations, CuO(001) has been identified as an active surface for methane oxidation. Experimental validation with CuO nanobelts comprised of predominantly (001) surfaces has been performed and it is confirmed that the performance of such nanobelts is much higher than normal nanoparticles and nanowires. First principle calculations further clarified that two-coordinated oxygen plays a key role for methane adsorption and oxidation.

It is well known that stem cells reside within tissue engineering functional microenvironments that physically localize them and direct their stem cell fate. Recent efforts in the development of more complex and engineered scaffold technologies, together with new understanding of stem cell behavior in vitro, have provided a new impetus to study regulation and directing stem cell fate. A variety of tissue engineering technologies have been developed to regulate the fate of stem cells. Traditional methods to change the fate of stem cells are adding growth factors or some signaling pathways. In recent years, many studies have revealed that the geometrical microenvironment played an essential role in regulating the fate of stem cells, and the physical factors of scaffolds including mechanical properties, pore sizes, porosity, surface stiffness, three-dimensional structures, and mechanical stimulation may affect the fate of stem cells. Chemical factors such as cell-adhesive ligands and exogenous growth factors would also regulate the fate of stem cells. Understanding how these physical and chemical cues affect the fate of stem cells is essential for building more complex and controlled scaffolds for directing stem cell fate.

Abstract Recent reported results by Fang et al. published in BMC Musculoskeletal Disorders have added to the weight of evidence supporting association between gluteal pain and lumbar disc hernia. Their clinical finding shows the L4/5 level is the main level responsible for gluteal pain in lumbar disc hernia. Indeed, many possible mechanisms may explain why patients experience pain in the gluteal area. In this Correspondence, we would like to highlight several possible mechanisms of LDH-related gluteal pain based on detailed analysis of the sensory innervation of the gluteal region. We hope this can better explain the phenomenon found by Fang et al. We believe the principle mechanism is compression/irritation of L5 or S1 dorsal rami (intraspinal portion), which produce gluteal pain by irritating superior/medial cluneal nerve and referred pain from facet joints and sacroiliac joints. In addition, the presence of proximal sciatica could also induce gluteal pain. Lastly, fibers in the superior or inferior gluteal nerve could be compressed/irritated in LDH, inducing LDH-related gluteal pain. However, additional studies are needed in the future to delineate the exact mechanism(s).

Although hydrogen sulfide (H2S) was always a negative factor leading to the reduction of hydrogen permeability of palladium (Pd) membranes, its proper application could result in a positive effect. In this study, pure Pd membranes were firstly reacted with H2S at 23–450 °C, and then treated by redox reactions. Afterwards, the hydrogen permeability was tested under different reaction conditions using a hydrogen penetrant testing device. Moreover, both products and morphology changes occurred on the Pd membrane surface were analyzed using XRD, XPS and SEM. The results showed that H2S was dissociated to produce sulfides at 23 °C. With a rise of temperature, a regular change took place in the reaction products, morphology of the Pd membrane surface and hydrogen permeability. Adsorbed impurities such as sulfides and free carbon on the Pd membrane surface were removed by the redox treatment. The hydrogen permeability was improved by about 80% for the Pd membrane material subjected to the treatment method stated the above against the untreated one.