Study on the safety and effectiveness of low-dose vs. regular-dose fondaparinux in preventing venous thromboembolism prophylaxis following total knee arthroplasty.

Background: This study aims to evaluate the effectiveness and safety of low-dose (1.5 mg) fondaparinux for venous thromboembolism (VTE) prophylaxis in patients post-total knee arthroplasty (TKA). Methods: We retrospectively identified 314 patients who carried out the primary TKAs and received fondaparinux for VTE chemoprophylaxis between July 2020 and December 2021. A total of 141 TKA patients were excluded according to the exclusion criteria. Two groups of patients were established: the low-dose group included 84 patients who injected 1.5 mg of fondaparinux, and the regular-dose group included 89 patients who injected 2.5 mg of fondaparinux. The pre-operative blood analysis and coagulation assays were performed. The surgical time, the incidence of symptomatic VET, blood loss, wound complication, bleeding, drainage, and mortality of patients were determined and assessed. Results: The pre-operative blood analysis, body mass index, sex, age, and coagulation assays of patients in both groups were comparable. In terms of symptomatic pulmonary embolism and deep vein thrombosis, there was no significant difference (variation) between the two groups. However, patients in both groups showed a substantial difference in terms of blood loss, drain volume, wound complication, and transfusion rate. Conclusion: In prevention of VET in patients post-TKA, low-dose fondaparin is as effective as conventional dose fondaparinux. A significant decrease in blood loss, post-surgical transfusion rates, and wound complications were detected in patients given low-dose fondaparinux compared to those receiving regular-dose fondaparinux.

Corrigendum: Coating of manganese functional polyetheretherketone implants for osseous interface integration.

[This corrects the article DOI: 10.3389/fbioe.2023.1182187.].

Coating of manganese functional polyetheretherketone implants for osseous interface integration.

Polyetheretherketone (PEEK) has been used extensively in biomedical engineering and it is highly desirable for PEEK implant to possess the ability to promote cell growth and significant osteogenic properties and consequently stimulate bone regeneration. In this study, a manganese modified PEEK implant (PEEK-PDA-Mn) was fabricated via polydopamine chemical treatment. The results showed that manganese was successfully immobilized on PEEK surface, and the surface roughness and hydrophilicity significantly improved after surface modification. Cell experiments in vitro demonstrated that the PEEK-PDA-Mn possesses superior cytocompatibility in cell adhesion and spread. Moreover, the osteogenic properties of PEEK-PDA-Mn were proved by the increased expression of osteogenic genes, alkaline phosphatase (ALP), and mineralization in vitro. Further rat femoral condyle defect model was utilized to assess bone formation ability of different PEEK implants in vivo. The results revealed that the PEEK-PDA-Mn group promoted bone tissue regeneration in defect area. Taken together, the simple immersing method can modify the surface of PEEK, giving outstanding biocompatibility and enhanced bone tissue regeneration ability to the modified PEEK, which could be applied as an orthopedic implant in clinical.

Microcrack Arrays in Dense Graphene Films for Fast-Ion-Diffusion Supercapacitors.

Laminated graphene film has great potential in compact high-power capacitive energy storage owing to the high bulk density and opened architecture. However, the high-power capability is usually limited by tortuous cross-layer ion diffusion. Herein, microcrack arrays are fabricated in graphene films as fast ion diffusion channels, converting tortuous diffusion into straightforward diffusion while maintaining a high bulk density of 0.92 g cm-3 . Films with optimized microcrack arrays exhibit sixfold improved ion diffusion coefficient and high volumetric capacitance of 221 F cm-3 (240 F g-1 ), representing a critical breakthrough in optimizing ion diffusion toward compact energy storage. This microcrack design is also efficient for signal filtering. Microcracked graphene-based supercapacitor with 30 µg cm-2  mass loading exhibits characteristic frequency up to 200 Hz with voltage window up to 4 V, showing high promise for compact, high-capacitance alternating current (AC) filtering. Moreover, a renewable energy system is conducted using microcrack-arrayed graphene supercapacitors as filter-capacitor and energy buffer, filtering and storing the 50 Hz AC electricity from a wind generator into the constant direct current, stably powering 74 LEDs, demonstrating enormous potential in practical applications. More importantly, this microcracking approach is roll-to-roll producible, which is cost-effective and highly promising for large-scale manufacture.

A dual-functional PEEK implant coating for anti-bacterial and accelerated osseointegration.

Polyetheretherketone (PEEK) has been widely applied in biomedical engineering. However, the unsatisfactory bioactivity essentially limits the clinical application of PEEK. In this study, a simply immersing method was proposed to fabricate a dual-functional PEEK with antibacterial properties and enhanced bone integration. Firstly, the surface of PEEK was modified with a polydopamine (PDA) coating by incubating at dopamine solution. Afterward, the PEEK-PDA was modified with manganese (Mn) and silver (Ag) ions by the soaking method to fabricate the PEEK-PDA-Mn/Ag. The physicochemical capabilities of PEEK-PDA-Mn/Ag were further explored in the ions release, wettability, morphology, and element distributions. PEEK-PDA-Mn/Ag obviously accelerated the adhesion and distribution of MC3T3-E1 cells, indicating favorable biosafety in vitro. Meanwhile, the osteogenic properties of PEEK-PDA-Mn and PEEK-PDA-Mn/Ag were proved by the increased expression of osteogenic genes, alkaline phosphatase (ALP), and mineralization in vitro. Additionally, the wide antibacterial capabilities of PEEK-PDA-Mn/Ag were proved in both Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) in vitro. Furthermore, the PEEK-PDA-Mn/Ag was antibacterial with capability in enhancing osseointegration in vivo. Overall, the simply immersing method can modify the surface of PEEK, giving the bioactivity, biocompatibility, and antibacterial ability to the composited PEEK, which could be applied as an orthopedic implant in clinical.

Integrated Analysis of Transcriptome Changes in Osteoarthritis: Gene Expression, Pathways and Alternative Splicing.

OBJECTIVE: Osteoarthritis (OA) is the most prevalent joint disease characterized by the degeneration of articular cartilage and the remodeling of its underlying bones, resulting in pain and loss of function in the knees and hips. As far as we know, no curative treatments are available except for the joint replacement. The precise molecular mechanisms which are involved in the degradation of cartilage matrix and development of osteoarthritis are still unclear. DESIGN: By analyzing RNA-seq data, we found the molecular changes at the transcriptome level such as alternative splicing, gene expression, and molecular pathways in OA knees cartilage. RESULTS: Expression analysis have identified 457 differential expressed genes including 266 up-regulated genes such as TNFSF15, ST6GALNAC5, TGFBI, ASPM, and TYM, and 191 down-regulated genes such as ADM, JUN, IRE2, PIGA, and MAFF. Gene set enrichment analysis (GSEA) analysis identified down-regulated pathways related to translation, transcription, immunity, PI3K/AKT, and circadian as well as disturbed pathways related to extracellular matrix and collagen. Splicing analysis identified 442 differential alternative splicing events within 284 genes in osteoarthritis, including genes involved in extracellular matrix (ECM) and alternative splicing, and TIA1 was identified as a key regulator of these splicing events. CONCLUSIONS: These findings provide insights into disease etiology, and offer favorable information to support the development of more effective interventions in response to the global clinical challenge of osteoarthritis.

Compact 3D Metal Collectors Enabled by Roll-to-Roll Nanoimprinting for Improving Capacitive Energy Storage.

Reducing the contact resistance between active materials and current collectors is of engineering importance for improving capacitive energy storage. 3D current collectors have shown extraordinary promise for reducing the contact resistance, however, there is a major obstacle of being bulky or inefficient fabrication before they become viable in practice. Here a roll-to-roll nanoimprinting method is demonstrated to deform flat aluminum foils into 3D current collectors with hierarchical microstructures by combining soft matter-enhanced plastic deformation and template-confined local surface nanocracks. The generated 3D current collectors are inserted by and interlocked with active electrode materials such as activated carbon, decreasing the contact resistance by at least one order of magnitude and quadrupling the specific capacitance at high current density of 30 A g-1 for commercial-level mass loading of 5 mg cm-2 . The 3D current collectors are so compact that they have a low volume percentage of 7.8% in the entire electrode film, resulting in energy and power density of 29.1 Wh L-1 and 12.8 kW L-1 , respectively, for stack cells in organic electrolyte. Furthermore, roll-to-roll nanoimprinting of metal microstructures is low-cost, high-throughput, and can be extended to other systems that involve the microstructured metal interface, such as batteries and thermal management.

Tuning the Mechanical and Electrical Properties of Porous Electrodes for Architecting 3D Microsupercapacitors with Batteries-Level Energy.

Microsupercapacitors (MSCs) are vital power sources for internet of things (IoTs) and miniaturized electronics. The performance of MSCs is often restricted by its low areal energy density, which is due to the low areal mass loading of active materials. Constructing thick planar microelectrode with fine structure and high aspect ratio is an efficient way to increase mass loading, but limited by the breakable nature of porous electrode materials. Here, it is found that the mechanical and electrical properties of porous electrodes, as well as their surface area utilization and internal ion diffusion pathway, can be synergistically tuned by infilling gel electrolyte into internal pores of porous electrode films. The tuned thick porous electrode films are robust enough to enable laser ablation of three dimensional (3D) microelectrodes for high mass loading and high aspect ratio. The areal capacitance of 3D microelectrodes is able to increase linearly with mass loading (or thickness) up to at least 13 mg cm-2  (or 260 µm) for a value of up to 4640 mF cm-2 based on active carbon. The 3D MSCs deliver areal energy density of 1318 µWh cm-2 , which is comparable to the best of Li-ion 3D microbatteries while exhibiting superior electrochemical and mechanical stability.

Scalable fabrication of high-performance micro-supercapacitors by embedding thick interdigital microelectrodes into microcavities.

Micro-supercapacitors (MSCs) with thick interdigital microelectrodes of carbon-based materials exhibit excellent electrochemical performance and hold tremendous promise for applications in microscale energy storage devices. Here, a scalable strategy to fabricate thick embedded multiwalled carbon nanotubes (MWCNTs) as interdigital microelectrodes for MSCs has been developed and investigated. To this end, sufficient MWNCT inks are firstly cast onto pre-patterned microcavity surfaces and then more MWCNT materials are embedded into the microcavities by rapid solvent evaporation. After removal of residual materials from the surfaces by a doctor-blading process, thick interdigital MWCNT microelectrodes with heights up to 190 µm are obtained. These embedded microelectrodes simplify the device structure and improve the mechanical flexibility by acting as both active materials and current collectors. Using interdigital microelectrodes with a width of 250 µm and an interspace of 50 µm, the fabricated MSCs exhibit outstanding electrochemical performance with a high capacitance of 19.5 mF cm-2 and an energy density of 2.48 µW h cm-2 at a power density of 24.7 µW cm-2. On the other hand, four light emitting diodes (LEDs) are successfully powered by three series of MSCs, indicating that MSCs can be connected in series and parallel to yield suitable operating voltages and currents for practical applications.

Oriented growth of cross-linked metal-organic framework film on graphene surface for non-enzymatic electrochemical sensor of hydrogen peroxide in disinfectant.

High-density and cross-linked copper-based metal-organic framework (Cu-MOF) sheets were successfully prepared via a simple oriented growth method on a carboxylated graphene-modified electrode surface. Hydrogen peroxide (H2O2) was selected as a model molecule to examine the performance of the thin film of Cu-MOF/graphene. The proposed sensor showed an extended linear detection range from 2.00 × 10-7 to 1.85 × 10-4 mol L-1 (R = 0.998), a high sensitivity of 0.792 A (mol L-1)-1, and a low detection limit of 6.7 × 10-8 mol L-1, due to the synergistic catalysis from the porous structure and favorable electron transfer mediating function of the electroactive Cu-MOFs and the high conductive property of the graphene. The reduction peak current of H2O2 changed less than 3.7% in the presence of 57-fold high concentrations (2.0 × 10-4 mol L-1) of the potential interfering species. The good selectivity of the prepared modified electrode was acquired by the size exclusion (molecular sieving) for H2O2 because of the proper pore shape and pore size of Cu-MOFs. The feasibility of the assay was verified by test of H2O2 in disinfectant samples. The proposed strategy presents valuable information related to the construction of non-enzymatic electrochemical sensors.

Maximum principles and Bôcher type theorems.

We establish maximum principles and Bôcher-type theorems for superharmonic and fractional superharmonic nonnegative functions on a punctured ball. Connecting maximum principles with Bôcher-type theorems is a crucial observation.

Graphene blended with SnO2 and Pd-Pt nanocages for sensitive non-enzymatic electrochemical detection of H2O2 released from living cells.

This paper described a novel, facile and nonenzymatic electrochemical biosensor to detect hydrogen peroxide (H2O2). The sensor was fabricated based on Pd-Pt nanocages and SnO2/graphene nanosheets modified electrode (PdPt NCs@SGN/GCE). The electrochemical behavior of PdPt NCs@SGN/GCE exhibited excellent catalytic activity toward H2O2 with fast response, high selectivity, superior sensitivity, low detection limit of 0.3 µM and large linear range from 1 µM to 300 µM. Under these obvious advantages, the constructed biosensor provided to be reliable for determination of H2O2 secreted from human cervical cancer cells (Hela cells). Hence, the proposed biosensor is a promising candidate for detection of H2O2 in situ released from living cells in clinical diagnostics.

Electrochemical Evaluation of trans-Resveratrol Levels in Red Wine Based on the Interaction between Resveratrol and Graphene.

trans-Resveratrol is often considered as one of the quality standards of red wine, and the development of a sensitive and reliable method for monitoring the trans-resveratrol levels in red wine is an urgent requirement for the quality control. Here, a novel voltammetric approach was described for probing trans-resveratrol using a graphene-modified glassy carbon (GC) electrode. The proposed electrode was prepared by one-step electrodeposition of reduced graphene oxide (ERGO) at a GC electrode. Compared with the bare GC electrode, the introduced graphene film on the electrode surface dramatically improved the sensitivity of the sensor response due to the π-π interaction between the graphene and trans-resveratrol. The developed sensor exhibited low detection limit of 0.2 µM with wide linear range of 0.8-32 µM and high stability. For the analysis of trans-resveratrol in red wine, the high anti-interference ability and the good recoveries indicated the great potential for practical applications.

Fabrication of an antibody-aptamer sandwich assay for electrochemical evaluation of levels of ß-amyloid oligomers.

Amyloid ß-peptide (Aß) in its oligomeric form is often considered as the most toxic species in Alzheimer's disease (AD), and thus Aß oligomer is a potentially promising candidate biomarker for AD diagnosis. The development of a sensitive and reliable method for monitoring the Aß oligomer levels in body fluids is an urgent requirement in order to predict the severity and progression at early or preclinical stages of AD. Here, we show a proof of concept for a sensitive and specific detection of Aß oligomers by an antibody-aptamer sandwich assay. The antibodies of Aß oligomers and a nanocomposite of gold nanoparticles with aptamer and thionine (aptamer-Au-Th) were used as the recognition element and the detection probe for specifically binding to Aß oligomers, respectively. The electrochemical signal of Th reduction could provide measurable electrochemical signals, and a low limit of detection (100 pM) was achieved due to the signal amplification by high loading of Th on the gold nanoparticles. The feasibility of the assay was verified by test of Aß oligomers in artificial cerebrospinal fluid. The proposed strategy presents valuable information related to early diagnosis of AD process.

(E)-2-Meth-oxy-N'-(4-nitro-benzyl-idene)benzohydrazide.

In the title compound, C(15)H(13)N(3)O(4), the mol-ecule exists in a trans configuration with respect to the methyl-idene unit. The dihedral angle between the two benzene rings is 6.8 (2)°. The C-N-NH-C torsion angle is 3.4 (3)°. The mol-ecule possesses an intra-molecular N-H⋯O hydrogen bond. In the crystal structure, adjacent mol-ecules are linked through inter-molecular C-H⋯O hydrogen bonds, forming dimers.

(E)-N'-[1-(2-Hydroxy-phen-yl)ethyl-idene]-3-methoxy-benzohydrazide.

In the title compound, C(16)H(16)N(2)O(3), the benzohydrazide group is not planar and the mol-ecule exists in a trans configuration with respect to the methyl-idene unit. The dihedral angle between the two substituted benzene rings is 26.9 (2)°. In the crystal structure, the mol-ecular packing is stabilized by intra-molecular O-H⋯N and inter-molecular N-H⋯O hydrogen bonds. The inter-molecular hydrogen bonding forms chains parallel to the b axis.

(E)-N'-(5-Bromo-2-methoxy-benzyl-idene)-3-methoxy-benzohydrazide.

In the title compound, C(16)H(15)BrN(2)O(3), there are two independent mol-ecules (A and B) in the asymmetric unit. The major difference between the two mol-ecules is the dihedral angle formed by the aromatic rings [72.6 (2) and 18.8 (2)° for A and B, respectively]. The benzohydrazide groups are not planar and the mol-ecules exist in trans configurations with respect to the methyl-idene units. The mol-ecular packing is stabilized by two inter-molecular N-H⋯O hydrogen bonds, forming chains parallel to the c axis. Only the A mol-ecules of the asymmetric unit are held together by π-π inter-actions [centroid-centroid distance = 3.714 (3) Å].

(E)-N'-(4-Hydroxy-benzyl-idene)-4-hydroxy-benzohydrazide methanol solvate.

The title compound, C(14)H(12)N(2)O(3)·CH(4)O, consists of a Schiff base mol-ecule and a methanol mol-ecule of crystallization. The Schiff base mol-ecule is nearly planar, the dihedral angle between the planes of the two benzene rings being 7.2 (2)°. The mol-ecule exists in the trans configuration with respect to the methyl-idene unit. In the crystal structure, the Schiff base and methanol mol-ecules are linked through O-H⋯O, N-H⋯O and O-H⋯N hydrogen bonds, forming a three-dimensional network.

(E)-4-Hydr-oxy-N'-(4-nitro-benzyl-idene)benzohydrazide.

The mol-ecule of the title compound, C(14)H(11)N(3)O(4), is approximately planar, the dihedral angle between the planes of the two substituted benzene rings being 2.54 (7)°. The mol-ecule exists in a trans configuration with respect to the central methyl-idene unit. In the crystal structure, mol-ecules are linked through inter-molecular O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds, forming layers parallel to (101). The O/N-H⋯O and C-H⋯O inter-actions form a pair of bifurcated acceptor bonds involving the cabon-yl/nitro O atom, generating an R(2) (1)(6) motif.

(E)-N'-(2-Chloro-5-nitro-benzyl-idene)-4-methoxy-benzohydrazide.

In the title compound, C(15)H(12)ClN(3)O(4), the benzohydrazide group is not planar and the mol-ecule exists in a trans configuration with respect to the methyl-idene unit. The dihedral angle between the two substituted benzene rings is 0.4 (3)°. In the crystal structure, mol-ecules are linked by inter-molecular N-H⋯O hydrogen bonds, forming chains parallel to the c axis.