Label-Free Multiplex Profiling of Exosomal Proteins with a Deep Learning-Driven 3D Surround-Enhancing SERS Platform for Early Cancer Diagnosis.

Identification of protein profiling on plasma exosomes by SERS can be a promising strategy for early cancer diagnosis. However, it is still challenging to detect multiple exosomal proteins simultaneously by SERS since the Raman signals of exosomes detected by conventional colloidal nanocrystals or two-dimensional SERS substrates are incomplete and complex. Herein, we develop a novel three-dimensional (3D) surround-enhancing SERS platform, named 3D se-SERS, for the multiplex detection of exosomal proteins. In this 3D se-SERS, proteins and exosomes are covered with "hotspots" generated by the gold nanoparticles, which surround the analytes densely and three-dimensionally, providing sensitive and comprehensive SERS signals. Combining this 3D se-SERS with a deep learning model, we successfully quantitatively profiled seven proteins including CD63, CD81, CD9, CD151, CD171, TSPAN8, and PD-L1 on the surface of plasma exosomes from patients, which can predict the occurrence and advancement of lung cancer. This 3D se-SERS integrating deep learning technique benefits from high sensitivity and significant multiplexing ability for comprehensive analysis of proteins and exosomes, demonstrating the potential of deep learning-driven 3D se-SERS technology for plasma exosome-based early cancer diagnosis.

Biomimetic nanodrug blocks CD73 to inhibit adenosine and boosts antitumor immune response synergically with photothermal stimulation.

Combination of tumor immunotherapy with photothermal therapy (PTT) is a feasible tactic to overcome the drawback of immunotherapy such as poor immune response. Via triggering the immunogenic cells death (ICD), PTT can stimulate the activity of immune cells, but meanwhile, the level of adenosine is elevated via the CD73-induced decomposition of ATP which is overexpressed accompanying with the PTT process, resulting in negative feedback to impair the immune stimulation. Herein, we developed a novel biomimetic photothermal nanodrug to specifically block CD73 for inhibition of adenosine production and more efficient priming of the suppressive immune microenvironments. The nanodrug, named as AptEM@CBA, is constructed by encapsulation of photothermal agent black phosphorus quantum dots (BPQDs) and selective CD73 inhibitor α, ß-Methyleneadenosine 5'-diphosphate (AMPCP) in chitosan nanogels, which are further covered with aptamer AS1411 modified erythrocyte membrane (EM) for biomimetic camouflage. With AS1411 induced active targeting and EM induced long blood circulation time, the enrichment of the nanodrug tumor sites is promoted. The photothermal treatment promotes the maturation of dendritic cells. Meanwhile, the release of AMPCP suppress the adenosine generation via CD73 blockade, alleviating the impairment of adenosine to dendritic cells and suppressing regulatory T cells, synergically stimulate the activity of T cells. The combination of CD73 blockade with PTT, not only suppresses the growth of primary implanted tumors, but also boosts strong antitumor immunity to inhibit the growth of distal tumors, providing good potential for tumor photoimmunotherapy.

A PD-L1 targeting nanotheranostic for effective photoacoustic imaging guided photothermal-immunotherapy of tumor.

Tumor immunotherapy has been partly effective for specific cancers. However, problems such as low immune response, limited antitumor effectiveness, and high antibody costs still persist. Synergistic therapeutic approaches, such as immune checkpoint inhibition in conjunction with photothermal therapy and photoacoustic imaging, are expected to provide approaches for more precise and efficient immunotherapy of tumors. Furthermore, developing alternatives for antibodies, such as PD-L1 aptamers and nanocarriers, would reduce the cost of tumor immunotherapy. Herein, we develop a PD-L1-targeting nanotheranostic to block immune checkpoints for synergistic photothermal-immunotherapy against tumors, along with effective photoacoustic (PA) imaging. The nanotheranostic is synthesized by the modification of gold nanorods (GNRs) with the PD-L1 aptamer (APDL1), which can sensitively and specifically recognize PD-L1 on the tumor cell surface, and mediate nanoparticle accumulation and strong PA signals in tumors. The aptamer is released from GNR through a competition of glutathione (GSH) and is then functionalized as a PD-L1 blockade. In collaboration with the concurrent photothermal therapy, antitumor immunity is significantly augmented by enhancing the filtration of matured dendritic cells and suppressing regulatory T cells, followed by the activation of cytotoxic T cells and inhibition of T cell exhaustion. Such a nanotheranostic modality effectively suppresses tumor growth in mice, representing an appealing platform for both biological imaging and photoimmunotherapy of tumors.

Successful LC-MS/MS assay development and validation for determination of valproic acid and its metabolites supporting proactive pharmacovigilance.

Valproic acid (VPA) is a well-documented contributor to liver injury, which is likely caused by the formation of its toxic metabolites. Monitoring VPA and its metabolites is very meaningful for the pharmacovigilance, but the availability of a powerful assay is a prerequisite. In this study, for the first time, a sensitive and specific LC-MS/MS method was developed and validated to simultaneously quantify the concentrations of VPA and its six pestering isomer metabolites (3-OH-VPA, 4-OH-VPA, 5-OH-VPA, 2-PGA, VPA-G, and 2-ene-VPA) in human plasma, using 5-OH-VPA-d7 and VPA-d6 as the internal standards (ISs). We also figured out another tricky problem that the concentrations of the parent drug and the metabolites vary widely. Of note, after protein precipitation and dilution with acetonitrile (ACN) and 50% ACN successively, the analytes and the ISs were successfully separated on a Kinetex C18 column. Intriguingly, sacrificing its signal intensity by elevated collision energy of VPA finally achieved the simultaneous determination. As expected, the method showed great linearity (r > 0.998) over the concentration ranges for all analytes. The inter-day and intra-day accuracy and precision were both acceptable. The method was successfully applied in 127 children with epilepsy. This novel assay will support the VPA-associated pharmacovigilance in the future.

Anti-BCMA surface engineered biomimetic photothermal nanomissile enhances multiple myeloma cell apoptosis and overcomes the disturbance of NF-κB signaling in vivo.

Conventional chemotherapy for multiple myeloma (MM) faces the challenges of a low complete remission rate and transformation to recurrence/refractory. The current MM first-line clinical drug Bortezomib (BTZ) faces the problem of enhanced tolerance and nonnegligible side effects. B cell maturation antigen (BCMA), for its important engagement in tumor signaling pathways and novel therapy technologies such as Chimeric antigen receptor T-Cell immunotherapy (CAR-T) and Antibody Drug Conjugate (ADC), has been identified as an ideal target and attracted attention in anti-MM therapy. Emerging nanotechnology provided feasible methods for drug delivery and new therapeutic strategies such as photothermal therapy (PTT). Herein, we developed a BCMA-Targeting biomimetic photothermal nanomissile BTZ@BPQDs@EM @anti-BCMA (BBE@anti-BCMA) by integration of BTZ, black phosphorus quantum dots (BPQDs), Erythrocyte membrane (EM) and BCMA antibody (anti-BCMA). We hypothesized that this engineered nanomissile could attack tumor cells in triple ways and achieve effective treatment of MM. Consequently, the intrinsic biomimetic nature of EM and the active targeting property of anti-BCMA enhanced the accumulation of therapeutic agents in the tumor site. Besides, owing to the decrease in BCMA abundance, the potential apoptosis-inducing ability was revealed. With the support of BPQDs' photothermal effect, Cleaved-Caspase-3 and Bax signal increased significantly, and the expression of Bcl-2 was inhibited. Furthermore, the synergistic photothermal/chemo therapy can effectively inhibit tumor growth and reverse the disorder of NF-κB in vivo. Importantly, this biomimetic nanodrug delivery system and antibody induced synergistic therapeutic strategy efficiently killed MM cells with ignorable systemic toxicity, which is a promising method for the future anticancer treatment of hematological malignancies in clinics.

All-Organic PTFE Coated PVDF Composite Film Exhibiting Low Conduction Loss and High Breakdown Strength for Energy Storage Applications.

Plastic film capacitors are widely used in pulse and energy storage applications because of their high breakdown strength, high power density, long lifetime, and excellent self-healing properties. Nowadays, the energy storage density of commercial biaxially oriented polypropylene (BOPP) is limited by its low dielectric constant (~2.2). Poly(vinylidene fluoride) (PVDF) exhibits a relatively high dielectric constant and breakdown strength, making it a candidate material for electrostatic capacitors. However, PVDF presents significant losses, generating a lot of waste heat. In this paper, under the guidance of the leakage mechanism, a high-insulation polytetrafluoroethylene (PTFE) coating is sprayed on the surface of a PVDF film. The potential barrier at the electrode-dielectric interface is raised by simply spraying PTFE and reducing the leakage current, and then the energy storage density is increased. After introducing the PTFE insulation coating, the high-field leakage current in the PVDF film shows an order of magnitude reduction. Moreover, the composite film presents a 30.8% improvement in breakdown strength, and a 70% enhancement in energy storage density is simultaneously achieved. The all-organic structure design provides a new idea for the application of PVDF in electrostatic capacitors.

Integrating metabolomics and lipidomics revealed a decrease in plasma fatty acids but an increase in triglycerides in children with drug-refractory epilepsy.

OBJECTIVE: The drug-refractory epilepsy (DRE) in children is commonly observed but the underlying mechanisms remain elusive. We examined whether fatty acids (FAs) and lipids are potentially associated with the pharmacoresistance to valproic acid (VPA) therapy. METHODS: This single-center, retrospective cohort study was conducted using data from pediatric patients collected between May 2019 and December 2019 at the Children's Hospital of Nanjing Medical University. Ninety plasma samples from 53 responders with VPA monotherapy (RE group) and 37 non-responders with VPA polytherapy (NR group) were collected. Non-targeted metabolomics and lipidomics analysis for those plasma samples were performed to compare the potential differences of small metabolites and lipids between the two groups. Plasma metabolites and lipids passing the threshold of variable importance in projection value >1, fold change >1.2 or <0.8, and p-value <0.05 were regarded as statistically different substances. RESULTS: A total of 204 small metabolites and 433 lipids comprising 16 different lipid subclasses were identified. The well-established partial least squares-discriminant analysis (PLS-DA) revealed a good separation of the RE from the NR group. The FAs and glycerophospholipids status were significantly decreased in the NR group, but their triglycerides (TG) levels were significantly increased. The trend of TG levels in routine laboratory tests was in line with the lipidomics analysis. Meanwhile, cases from the NR group were characterized by a decreased level of citric acid and L-thyroxine, but with an increased level of glucose and 2-oxoglutarate. The top two enriched metabolic pathways involved in the DRE condition were biosynthesis of unsaturated FAs and linoleic acid metabolism. SIGNIFICANCE: The results of this study suggested an association between metabolism of FAs and the medically intractable epilepsy. Such novel findings might propose a potential mechanism linked to the energy metabolism. Ketogenic acid and FAs supplementation might therefore be high-priority strategies for DRE management.

Synthesis of a Systematic 64-Membered Heparan Sulfate Tetrasaccharide Library.

Heparan sulfate (HS) has multifaceted biological activities. To date, no libraries of HS oligosaccharides bearing systematically varied sulfation structures are available owing to the challenges in synthesizing a large number of HS oligosaccharides. To overcome the obstacles and expedite the synthesis, a divergent approach was designed, where 64 HS tetrasaccharides covering all possible structures of 2-O-, 6-O- and N-sulfation with the glucosamine-glucuronic acid-glucosamine-iduronic acid backbone were successfully produced from a single strategically protected tetrasaccharide intermediate. This extensive library helped identify the structural requirements for HS sequences to have strong fibroblast growth factor-2 binding but a weak affinity for platelet factor-4. Such a strategy to separate out these two interactions could lead to new HS-based potential therapeutics without the dangerous adverse effect of heparin-induced thrombocytopenia.

The Role of Single Nucleotide Polymorphisms in Transporter Proteins and the Folate Metabolism Pathway in Delayed Methotrexate Excretion: A Case Report and Literature Review.

High-dose methotrexate (HDMTX) is a pivotal component of the chemotherapeutic regimens of osteosarcoma. However, the use of HDMTX is limited by an increased risk of dose-dependent toxicity. It is thought that the plasma levels and therapy-related toxicity of MTX could be associated with single nucleotide polymorphisms (SNPs) within MTX metabolism pathway genes. Here, we report a case of a paediatric osteosarcoma girl with delayed MTX excretion who was successfully managed using supportive measures and continuous veno-venous haemodiafiltration. We further identified the cause that could account for delayed elimination by genotyping analysis. The results showed that variations have been found in SLCO1B1, SLC19A1, ABCB1 and MTHFR, all those were reported to have a strong association with delayed elimination of MTX in clinical studies. After comprehensive consideration of genotype and clinical phenotype, the second course of HDMTX was administered to this patient at a half reduced dose. We also performed a literature review to summarize the pharmacogenetic factors that influence HDMTX pharmacokinetics or MTX-related adverse effects in osteosarcoma patients. It is suggested that the potential risk of delayed MTX elimination is worthy of clinical attention, and the implementation of genotyping should be considered to ensure therapeutic safety.

Optimizing thiopurine therapy in children with acute lymphoblastic leukemia: A promising "MINT" sequencing strategy and therapeutic "DNA-TG" monitoring.

Thiopurines, including thioguanine (TG), 6-mercaptopurine (6-MP), and azathioprine (AZA), are extensively used in clinical practice in children with acute lymphoblastic leukemia (ALL) and inflammatory bowel diseases. However, the common adverse effects caused by myelosuppression and hepatotoxicity limit their application. Metabolizing enzymes such as thiopurine S-methyltransferase (TPMT), nudix hydrolase 15 (NUDT15), inosine triphosphate pyrophosphohydrolase (ITPA), and drug transporters like multidrug resistance-associated protein 4 (MRP4) have been reported to mediate the metabolism and transportation of thiopurine drugs. Hence, the single nucleotide polymorphisms (SNPs) in those genes could theoretically affect the pharmacokinetics and pharmacological effects of these drugs, and might also become one of the determinants of clinical efficacy and adverse effects. Moreover, long-term clinical practices have confirmed that thiopurine-related adverse reactions are associated with the systemic concentrations of their active metabolites. In this review, we mainly summarized the pharmacogenetic studies of thiopurine drugs. We also evaluated the therapeutic drug monitoring (TDM) research studies and focused on those active metabolites, hoping to continuously improve monitoring strategies for thiopurine therapy to maximize therapeutic efficacy and minimize the adverse effects or toxicity. We proposed that tailoring thiopurine dosing based on MRP4, ITPA, NUDT15, and TMPT genotypes, defined as "MINT" panel sequencing strategy, might contribute toward improving the efficacy and safety of thiopurines. Moreover, the DNA-incorporated thioguanine nucleotide (DNA-TG) metabolite level was more suitable for red cell 6-thioguanine nucleotide (6-TGNs) monitoring, which can better predict the efficacy and safety of thiopurines. Integrating the panel "MINT" sequencing strategy with therapeutic "DNA-TG" monitoring would offer a new insight into the precision thiopurine therapy for pediatric acute lymphoblastic leukemia patients.

Comparison of LC-MS/MS and EMIT methods for the precise determination of blood sirolimus in children with vascular anomalies.

Sirolimus (SRL) is a mammalian target of rapamycin (mTOR) inhibitor. The whole blood concentration of SRL is routinely monitored to tailor dosage and prevent toxicity. Currently, the enzyme multiplied immunoassay technique (EMIT) is often applied to perform therapeutic drug monitoring (TDM) of SRL, but the cross-reactivity with various metabolites is of great concern. A more specific method is required, such as liquid chromatography-tandem mass spectrometry (LC-MS/MS). However, no study on the method comparison of the EMIT and LC-MS/MS for the measurement of whole blood SRL concentration in children with vascular anomalies has been reported. This study developed a simple and sensitive LC-MS/MS assay for the determination of SRL. Meanwhile, consistency between LC-MS/MS and the EMIT was evaluated by linear regression and Bland-Altman analysis. Whole blood samples were deproteinized with methanol for erythrocyte lysis, and the resulting solution was injected into the LC-MS/MS system using the positive electrospray ionization mode. The multiple reaction monitoring transitions of m/z 931.7 → 864.6 and m/z 934.7 → 864.6 were used for SRL and SRL-d3 as the internal standards, respectively. The analytes were separated on a C18 column with a gradient mobile phase (0.1 mM formic acid and 0.05 mM ammonium acetate in methanol/ultrapure water). Blood samples collected from children with vascular anomalies undergoing SRL therapy were tested by EMIT and by LC-MS/MS. The linear range of LC-MS/MS was 0.500-50.0 ng/ml and that of the EMIT was 3.50-30.0 ng/ml. A significant positive correlation between the two assays was established with a regression equation described as [ EMIT ] = 1.281 × [ LC-MS/MS ] + 2.450 (r = 0.8361). Bland-Altman plots showed a mean concentration overestimation of 4.7 ng/ml [95% CI: (-3.1, 12.6)] and a positive bias of 63.1% [95% CI: (-36.1, 162.3)] generated by the EMIT more than that of by LC-MS/MS. In conclusion, the two methods were closely correlated, indicating that switching between the two methods is feasible. Considering the overestimation nature of the EMIT assay, switching from the EMIT to the LC-MS/MS method deserves close attention and necessary re-evaluation for the target therapeutic reference range, may be required when methods are switched within the same clinical laboratory or results are compared between different laboratories.

Therapeutic drug monitoring of perampanel in children diagnosed with epilepsy: Focus on influencing factors on the plasma concentration-to-dose ratio.

OBJECTIVE: This study aimed to investigate the efficacy and tolerability of perampanel (PER) therapy and to optimize a specific plasma reference range for PER in children. Another major aim was to evaluate the potential determinators of PER concentration. METHODS: Concentrations obtained from 80 children were analyzed for routine therapeutic drug monitoring (TDM) between 2021 and 2022. We retrospectively reviewed the clinical data of these patients and assessed the efficacy at 3 months after treatment initiation. Trough concentration-to-dose ratio (C0 /Dose ratio) of PER was compared among patients on various potential influencing factors. RESULTS: A 3-month PER therapy produced a ≥50% reduction in seizure frequency in 58.8% of patients. Twelve patients reported at least one adverse effect (AE), mainly dizziness. The monitoring data showed that the median C0 was 325.5 ng/mL. Under maintenance dosages, approximately 75% of the C0 values were 180.0-610.0 ng/mL. The C0 /Dose ratio in patients aged 1 to <4 was significantly lower by twofold than in those aged 4 to ≤12 years (P = 0.001). Enzyme-inducing ASMs (EIASMs) decreased the C0 /Dose ratio of PER by 25.9% (P = 0.165). In addition, seizure frequency reduction in responders was achieved at a median PER C0 value of 357 ng/mL, which was similar to the value of 314 ng/mL found in nonresponders (P = 0.288). No significant difference was found in PER C0 values between patients with and without AEs (P = 0.082). SIGNIFICANCE: In this study, PER treatment showed acceptable efficacy and tolerance in Chinese children with epilepsy. Contributing factors like age to variable C0 /Dose ratios were identified, and complex PER-ASMs interactions were observed. Notably, the reference range, that is, 180.0-610.0 ng/mL, for routine PER monitoring may be more applicable for them. Routine TDM should be considered a positive attempt to manage the effectiveness and safety of PER.

Assembly of Poly(ethylene glycol)ylated Oleanolic Acid on a Linear Polymer as a Pseudomucin for Influenza Virus Inhibition and Adsorption.

Biomimicry of the mucin barrier function is an efficient strategy to counteract influenza. We report the simple aminolyzation of poly(methyl vinyl ether-alt-maleic anhydride) (PM) using amine-terminated poly(ethylene glycol)ylated oleanolic acid (OAPEG) to mimic the mucin structure and its adsorption of the influenza virus. Direct interactions between influenza hemagglutinin (HA) and the prepared macromolecule evaluated by surface plasmon resonance and isothermal titration calorimetry demonstrated that the multivalent presentation of OAPEG on PM enhanced the binding affinity to HA with a decrease in KD of approximately three orders of magnitude compared with monomeric OAPEG. Moreover, hemagglutination inhibition assay, viral growth inhibition assay, and cytopathic effect reduction assay indicated that the nonglycosylated polymer could mimic natural heavily glycosylated mucin and thus promote the attachment of the virus in a subnanomolar range. Further investigation of the antiviral effects via time-of-addition assay, dynamic light scattering experiments, and transmission electron microscopy photographs indicated that the pseudomucin could adsorb the virion particles and synergistically inhibit the early attachment and final release steps of the influenza infection cycle. These findings demonstrate the effectiveness of the macromolecule in the physical sequestration and prevention of viral infection. Notably, due to its structural similarities with mucin, the biomacropolymer also has the potential for the rational design of antiviral drugs, influenza adsorbents, or filtration materials and the construction of model systems to explore protection against other pathogenic viruses.

Oseltamivir modified bovine serum albumin inhibits neuraminidase activity and accumulates virion particles to disturb influenza virus replication.

The preparation of oseltamivir-bovine serum albumin conjugate (OS-BSA) for use as a multivalent influenza neuraminidase (NA) inhibitor is reported. Briefly, the oseltamivir azidohexyl ester was synthesized and covalently bound via an orthogonal attachment to bicyclononyne-modified BSA using copper-free click chemistry. Primary antiviral assays on NA protein and cellular levels showed that the synthetic multivalent OS-BSA conjugate was a more effective inhibitor than monomeric OS azidohexyl ester. Further investigation of the antiviral mechanism found that the prepared OS-BSA could not only be used as a multivalent NA inhibitor but also acted as an adsorbent for the aggregation of virion particles, contributing to the inhibition of the influenza viral replication cycle. Our findings provide insight into the antiviral mechanism of multivalent NA inhibitors and form a basis for the development of novel antiviral agents.

Upregulated GATA3/miR205-5p Axis Inhibits MFNG Transcription and Reduces the Malignancy of Triple-Negative Breast Cancer.

Triple-negative breast cancer (TNBC) accounts for approximately 20% of all breast carcinomas and has the worst prognosis of all breast cancer subtypes due to the lack of an effective target. Therefore, understanding the molecular mechanism underpinning TNBC progression could explore a new target for therapy. While the Notch pathway is critical in the development process, its dysregulation leads to TNBC initiation. Previously, we found that manic fringe (MFNG) activates the Notch signaling and induces breast cancer progression. However, the underlying molecular mechanism of MFNG upstream remains unknown. In this study, we explore the regulatory mechanisms of MFNG in TNBC. We show that the increased expression of MFNG in TNBC is associated with poor clinical prognosis and significantly promotes cell growth and migration, as well as Notch signaling activation. The mechanistic studies reveal that MFNG is a direct target of GATA3 and miR205-5p and demonstrate that GATA3 and miR205-5p overexpression attenuate MFNG oncogenic effects, while GATA3 knockdown mimics MFNG phenotype to promote TNBC progression. Moreover, we illustrate that GATA3 is required for miR205-5p activation to inhibit MFNG transcription by binding to the 3' UTR region of its mRNA, which forms the GATA3/miR205-5p/MFNG feed-forward loop. Additionally, our in vivo data show that the miR205-5p mimic combined with polyetherimide-black phosphorus (PEI-BP) nanoparticle remarkably inhibits the growth of TNBC-derived tumors which lack GATA3 expression. Collectively, our study uncovers a novel GATA3/miR205-5p/MFNG feed-forward loop as a pathway that could be a potential therapeutic target for TNBC.

Ag nanoparticles enhance immune checkpoint blockade efficacy by promoting of immune surveillance in melanoma.

Immune checkpoint blockade (ICB) therapy, represented by programmed cell death protein 1 (PD-1) and its ligand (PD-L1) monoclonal antibodies (mAbs), has shown an obvious benefit for melanoma immunotherapy, but the overall response rate is still low. To find an effective combination therapy strategy, we successfully produced small size silver nanoparticles coated with sucrose (S-AgNPs) as potent adjuvants. The antitumor effects of S-AgNPs were tested in vitro and comparatively investigated in immunodeficient and immunocompetent mice with melanoma. Fluorescence-activated cell sorting and immunofluorescent staining analysis were conducted to identify the tumor microenvironments. The expression of PD-L1 in tumors was tested by multiple methods. The combination therapy and potential toxicity of S-AgNPs and PD-1 mAbs were assessed in melanoma-bearing mice. In our findings, S-AgNPs presented potent antitumor effects, good druggability and low systemic toxicity. Functionally, we found that S-AgNPs exhibited better antitumor effects in immunocompetent mice. Mechanistically, we showed that S-AgNPs suppress tumor cell proliferation by inducing cellular apoptosis and promote cytotoxic CD8+ T cell infiltration and activity. Preclinically, S-AgNPs showed excellent local antitumor activity and mild systemic immunotoxicity with PD-1 mAbs in the inhibition of melanoma proliferation, providing a novel clinical combination treatment strategy.

Nanoscale Modification of Titanium Implants Improves Behaviors of Bone Mesenchymal Stem Cells and Osteogenesis In Vivo.

The surficial micro/nanotopography and physiochemical properties of titanium implants are essential for osteogenesis. However, these surface characters' influence on stem cell behaviors and osteogenesis is still not fully understood. In this study, titanium implants with different surface roughness, nanostructure, and wettability were fabricated by further nanoscale modification of sandblasted and acid-etched titanium (SLA: sandblasted and acid-etched) by H2O2 treatment (hSLAs: H2O2 treated SLA). The rat bone mesenchymal stem cells (rBMSCs: rat bone mesenchymal stem cells) are cultured on SLA and hSLA surfaces, and the cell behaviors of attachment, spreading, proliferation, and osteogenic differentiation are further analyzed. Measurements of surface characteristics show hSLA surface is equipped with nanoscale pores on microcavities and appeared to be hydrophilic. In vitro cell studies demonstrated that the hSLA titanium significantly enhances cell response to attachment, spreading, and proliferation. The hSLAs with proper degree of H2O2 etching (h1SLA: treating SLA with H2O2 for 1 hour) harvest the best improvement of differentiation of rBMSCs. Finally, the osteogenesis in beagle dogs was tested, and the h1SLA implants perform much better bone formation than SLA implants. These results indicate that the nanoscale modification of SLA titanium surface endowing nanostructures, roughness, and wettability could significantly improve the behaviors of bone mesenchymal stem cells and osteogenesis on the scaffold surface. These nanoscale modified SLA titanium scaffolds, fabricated in our study with enhanced cell affinity and osteogenesis, had great potential for implant dentistry.

Chemoenzymatic Synthesis of 9NHAc-GD2 Antigen to Overcome the Hydrolytic Instability of O-Acetylated-GD2 for Anticancer Conjugate Vaccine Development.

Ganglioside GD2 is an attractive tumor-associated carbohydrate antigen for anti-cancer vaccine development. However, its low immunogenicity and the significant side effects observed with anti-GD2 antibodies present significant obstacles for vaccines. To overcome these, a new GD2 derivative bearing an N-acetamide (NHAc) at its non-reducing end neuraminic acid (9NHAc-GD2) has been designed to mimic the 9-O-acetylated-GD2 (9OAc-GD2), a GD2 based antigen with a restricted expression on tumor cells. 9NHAc-GD2 was synthesized efficiently via a chemoenzymatic method and subsequently conjugated with a powerful carrier bacteriophage Qß. Mouse immunization with the Qß-9NHAc-GD2 conjugate elicited strong and long-lasting IgG antibodies, which were highly selective toward 9NHAc-GD2 with little cross-recognition of GD2. Immunization of canines with Qß-9NHAc-GD2 showed the construct was immunogenic in canines with little adverse effects, paving the way for future clinical translation to humans.

Sandwich-structured poly(vinylidene fluoride-hexafluoropropylene) composite film containing a boron nitride nanosheet interlayer.

High performance dielectric polymer materials are a key point for energy storage capacitors, especially film capacitors. In this paper, a sandwich-structured polymer film is constructed to achieve high energy density and high efficiency. High dielectric materials of poly(vinylidene fluoride-hexafluoropropylene) (P(VDF-HFP)) doped with barium titanate (BaTiO3) are used as the outer layer to achieve a high dielectric constant, and a boron nitride nanosheet (BNNS) layer is inserted between P(VDF-HFP)/BaTiO3 to obtain a high breakdown field strength of composite films. The results indicate that when the doping amount of the BaTiO3 nanoparticles reaches 10 wt% and the mass fraction of the BNNS layer is 0.75 wt%, a significant improvement of energy storage performance is obtained. The energy storage density of the P(VDF-HFP)/BaTiO3/BNNSs composite film can reach 8.37 J cm-3, which is higher than 6.65 J cm-3 of the pure P(VDF-HFP) film. Compared with the P(VDF-HFP) film doped with BaTiO3, significant improvement of the breakdown field strength (about 148.5%) is achieved and the energy storage density increases 235% accordingly, resulting from the inserted BNNSs layer blocking the growth of electrical branches and suppressing leakage current. This novel sandwich-structured film shows promising future applications for high performance dielectric capacitors.