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1.
J Am Chem Soc ; 146(10): 6628-6637, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38359144

RESUMO

Currently, the desired research focus in energy storage technique innovation has been gradually shifted to next-generation aqueous batteries holding both high performance and sustainability. However, aqueous Zn-I2 batteries have been deemed to have great sustainable potential, owing to the merits of cost-effective and eco-friendly nature. However, their commercial application is hindered by the serious shuttle effect of polyiodides during reversible operations. In this work, a Janus functional binder based on chitosan (CTS) molecules was designed and prepared; the polar terminational groups impart excellent mechanical robustness to hybrid binders; meanwhile, it can also deliver isochronous enhancement on physical adsorption and redox kinetics toward I2 species. By feat of highly effective remission to shuttle effect, the CTS cell exhibits superb electrochemical storage capacities with long-term robustness, specifically, 144.1 mAh g-1, at a current density of 0.2 mA g-1 after 1500 cycles. Simultaneously, the undesired self-discharging issue could be also well-addressed; the Coulombic efficiency could remain at 98.8 % after resting for 24 h. More importantly, CTS molecules endow good biodegradability and reusable properties; after iodine species were reloaded, the recycled devices could also deliver specific capacities of 73.3 mAh g-1, over 1000 cycles. This Janus binder provides a potential synchronous solution to realize high comprehensive performance with high iodine utilization and further make it possible for sustainable Zn-I2 batteries.

2.
J Am Chem Soc ; 146(7): 4652-4664, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38265705

RESUMO

Since sodium-ion batteries (SIBs) have become increasingly commercialized in recent years, Na3V2(PO4)2O2F (NVPOF) offers promising economic potential as a cathode for SIBs because of its high operating voltage and energy density. According to reports, NVPOF performs poorly in normal commercial poly(vinylidene fluoride) (PVDF) binder systems and performs best in combination with aqueous binder. Although in line with the concept of green and sustainable development for future electrode preparation, aqueous binders are challenging to achieve high active material loadings at the electrode level, and their relatively high surface tension tends to cause the active material on the electrode sheet to crack or even peel off from the collector. Herein, a cross-linkable and easily commercial hybrid binder constructed by intermolecular hydrogen bonding (named HPP) has been developed and utilized in an NVPOF system, which enables the generation of a stable cathode electrolyte interphase on the surface of active materials. According to theoretical simulations, the HPP binder enhances electronic/ionic conductivity, which greatly lowers the energy barrier for Na+ migration. Additionally, the strong hydrogen-bond interactions between the HPP binder and NVPOF effectively prevent electrolyte corrosion and transition-metal dissolution, lessen the lattice volume effect, and ensure structural stability during cycling. The HPP-based NVPOF offers considerably improved rate capability and cycling performance, benefiting from these benefits. This comprehensive binder can be extended to the development of next-generation energy storage technologies with superior performance.

3.
J Am Chem Soc ; 146(11): 7295-7304, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38364093

RESUMO

All-weather operation is considered an ultimate pursuit of the practical development of sodium-ion batteries (SIBs), however, blocked by a lack of suitable electrolytes at present. Herein, by introducing synergistic manipulation mechanisms driven by phosphorus/silicon involvement, the compact electrode/electrolyte interphases are endowed with improved interfacial Na-ion transport kinetics and desirable structural/thermal stability. Therefore, the modified carbonate-based electrolyte successfully enables all-weather adaptability for long-term operation over a wide temperature range. As a verification, the half-cells using the designed electrolyte operate stably over a temperature range of -25 to 75 °C, accompanied by a capacity retention rate exceeding 70% even after 1700 cycles at 60 °C. More importantly, the full cells assembled with Na3V2(PO4)2O2F cathode and hard carbon anode also have excellent cycling stability, exceeding 500 and 1000 cycles at -25 to 50 °C and superb temperature adaptability during all-weather dynamic testing with continuous temperature change. In short, this work proposes an advanced interfacial regulation strategy targeted at the all-climate SIB operation, which is of good practicability and reference significance.

4.
Small ; 20(11): e2311024, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38239090

RESUMO

Sodium-ion batteries (SIBs) have gradually become one of the most promising energy storage techniques in the current era of post-lithium-ion batteries. For anodes, transitional metal selenides (TMSe) based materials are welcomed choices , owing to relatively higher specific capacities and enriched redox active sites. Nevertheless, current bottlenecks are blamed for their poor intrinsic electronic conductivities, and uncontrollable volume expansion during redox reactions. Given that, an interfacial-confined isochronous conversion strategy is proposed, to prepare orthorhombic/cubic biphasic TMSe heterostructure, namely CuSe/Cu3 VSe4 , through using MXene as the precursor, followed by Cu/Se dual anchorage. As-designed biphasic TMSe heterostructure endows unique hierarchical structure, which contains adequate insertion sites and diffusion spacing for Na ions, besides, the surficial pseudocapacitive storage behaviors can be also proceeded like 2D MXene. By further investigation on electronic structure, the theoretical calculations indicate that biphasic CuSe/Cu3 VSe4 anode exhibits well-enhanced properties, with smaller bandgap and thus greatly improves intrinsic poor conductivities. In addition, the dual redox centers can enhance the electrochemical Na ions storage abilities. As a result, the as-designed biphasic TMSe anode can deliver a reversible specific capacity of 576.8 mAh g-1 at 0.1 A g-1 , favorable Na affinity, and reduced diffusion barriers. This work discloses a synchronous solution toward demerits in conductivities and lifespan, which is inspiring for TMSe-based anode development in SIBs systems.

5.
Angew Chem Int Ed Engl ; 63(12): e202316925, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38284505

RESUMO

During multivalent ions insertion processes, intense electrostatic interaction between charge carriers and host makes the high-performance reversible Al3+ storage remains an elusive target. On account of the strong electrostatic repulsion and poor robustness, Prussian Blue analogues (PBAs) suffer severely from the inevitable and large strain and phase change during reversible Al3+ insertion. Herein, we demonstrate an entropy-driven strategy to realize ultralong life aqueous Al-ion batteries (AIBs) based on medium entropy PBAs (ME-PBAs) host. By multiple redox active centers introduction, the intrinsic poor conductivity can be enhanced simultaneously, resulting in outstanding capabilities of electrochemical Al3+ storage. Meanwhile, the co-occupation at metal sites in PBA frameworks can also increase the M-N bond intensity, which is beneficial for constraining the phase change during consecutive Al3+ reversible insertion, to realize an extended lifespan over 10,000 cycles. Based on the calculation at different operation states, the fluctuation of ME-PBA lattice parameters is only 1.2 %. Assembled with MoO3 anodes, the full cells can also deliver outstanding electrochemical properties. The findings highlight that, the entropy regulation strategy could uncover the isochronous constraint on both strain and phase transition for long-term reversible Al3+ storage, providing a promising design for advanced electrode materials for aqueous multivalent ions batteries.

6.
Angew Chem Int Ed Engl ; 62(15): e202300258, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36721269

RESUMO

Sodium-ion batteries (SIBs) have great potential for large-scale energy storage. Cellulose is an attractive material for sustainable separators, but some key issues still exist affecting its application. Herein, a cellulose-based composite separator (CP@PPC) was prepared by immersion curing of cellulose-based separators (CP) with poly(propylene carbonate) (PPC). With the assistance of PPC, the CP@PPC separator is able to operate the cell stably at high voltages (up to 4.95 V). The "pore-hopping" ion transport mechanism in CP@PPC opens up extra Na+ migration paths, resulting in a high Na+ transference number (0.613). The separator can also tolerate folding, bending and extreme temperature under certain circumstances. Full cells with CP@PPC reveal one-up capacity retention (96.97 %) at 2C after 500 cycles compared to cells with CP. The mechanism highlights the merits of electrolyte analogs in separator modification, making a rational design for durable devices in advanced energy storage systems.

7.
Gastrointest Endosc ; 96(1): 140-147, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35065045

RESUMO

BACKGROUND AND AIMS: Effective countertraction is a main challenging issue in endoscopic submucosal dissection (ESD). Several countertraction methods have been developed to address this issue. The aim of this study was to compare the efficacy of ESD using a novel simplified robot, the flexible auxiliary single-arm transluminal endoscopic robot (FASTER), with a traditional technique. METHODS: This was a prospective, randomized animal study. Forty-eight ESDs in 6 pigs were carried out at 8 different locations (gastric antrum, gastric body, lower esophagus, and middle esophagus) by the conventional method (n = 24) and by the FASTER-assisted method (n = 24). The primary outcomes were total procedure time, dissection time, and rate of direct-vision dissection. Secondary endpoints were completeness of en-bloc resection and adverse event rate. RESULTS: The total procedure time was significantly shorter in FASTER-assisted ESD than in conventional ESD (18.8 vs 32.8 minutes; P < .001). In contrast to the median direct-vision dissection rate of 73% with conventional ESD, the FASTER-assisted group had a significantly higher rate of 96% (P < .001). The number of sites of muscular damage was significantly lower using the FASTER-assisted method than the conventional method (6 vs 21, respectively; P = .018). This improvement was more apparent in esophageal lesions compared with gastric lesions. CONCLUSIONS: This study demonstrated that using a simplified robot during ESD is technically feasible and enables the endoscopist to dynamically use countertraction. This device could significantly reduce procedure time compared with conventional ESD techniques.


Assuntos
Ressecção Endoscópica de Mucosa , Robótica , Gastropatias , Animais , Dissecação/métodos , Ressecção Endoscópica de Mucosa/métodos , Esôfago/cirurgia , Humanos , Estudos Prospectivos , Suínos , Resultado do Tratamento
8.
Molecules ; 27(3)2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35164276

RESUMO

A series of new thiazole-based stilbene analogs were designed, synthesized and evaluated for DNA topoisomerase IB (Top1) inhibitory activity. Top1-mediated relaxation assays showed that the synthesized compounds possessed variable Top1 inhibitory activity. Among them, (E)-2-(3-methylstyryl)-4-(4-fluorophenyl)thiazole (8) acted as a potent Top1 inhibitor with high Top1 inhibition of ++++ which is comparable to that of CPT. A possible binding mode of compound 8 with Top1-DNA complex was further provided by molecular docking. An MTT assay against human breast cancer (MCF-7) and human colon cancer (HCT116) cell lines revealed that the majority of these compounds showed high cytotoxicity, with IC50 values at micromolar concentrations. Compounds 8 and (E)-2-(4-tert-butylstyryl)-4-(4-fluorophenyl)thiazole (11) exhibited the most potent cytotoxicity with IC50 values of 0.78 and 0.62 µM against MCF-7 and HCT116, respectively. Moreover, the preliminary structure-activity relationships of thiazole-based stilbene analogs was also discussed.


Assuntos
Antineoplásicos/química , Estilbenos/química , Tiazóis/química , Inibidores da Topoisomerase/química , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Desenho de Fármacos , Células HCT116 , Humanos , Células MCF-7 , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Estilbenos/síntese química , Estilbenos/farmacologia , Tiazóis/síntese química , Tiazóis/farmacologia , Inibidores da Topoisomerase/síntese química , Inibidores da Topoisomerase/farmacologia
9.
Angew Chem Int Ed Engl ; 60(51): 26837-26846, 2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34636126

RESUMO

Although ether-based electrolytes have been extensively applied in anode evaluation of batteries, anodic instability arising from solvent oxidability is always a tremendous obstacle to matching with high-voltage cathodes. Herein, by rational design for solvation configuration, the fully coordinated ether-based electrolyte with strong resistance against oxidation is reported, which remains anodically stable with high-voltage Na3 V2 (PO4 )2 O2 F (NVPF) cathode under 4.5 V (versus Na+ /Na) protected by an effective interphase. The assembled graphite//NVPF full cells display superior rate performance and unprecedented cycling stability. Beyond that, the constructed full cells coupling the high-voltage NVPF cathode with hard carbon anode exhibit outstanding electrochemical performances in terms of high average output voltage up to 3.72 V, long-term cycle life (such as 95 % capacity retention after 700 cycles) and high energy density (247 Wh kg-1 ). In short, the optimized ether-based electrolyte enriches systematic options, the ability to maintain oxidative stability and compatibility with various anodes, exhibiting attractive prospects for application.

10.
Bioconjug Chem ; 29(2): 546-558, 2018 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-29346731

RESUMO

PENAO (4-(N-(S-penicillaminylacetyl)amino) phenylarsonous acid), which is a mitochondria inhibitor that reacts with adenine nucleotide translocator (ANT), is currently being trialed in patients with solid tumors. To increase the stability of the drug, the formation of nanoparticles has been proposed. Herein, the direct synthesis of polymeric micelles based on the anticancer drug PENAO is presented. PENAO is readily available for amidation reaction to form PENAO MA (4-(N-(S-penicillaminylacetyl) amino) phenylarsonous acid methacrylamide) which undergoes RAFT (reversible addition-fragmentation chain transfer) polymerization with poly(ethylene glycol methyl ether methacrylate) as comonomer and poly(methyl methacrylate) (pMMA) as chain transfer agent, resulting in p(MMA)-b-p(PEG-co-PENAO) block copolymers with 3-15 wt % of PENAO MA. The different block copolymers self-assembled into micelle structures, varying in size and stability (Dh = 84-234 nm, cmc = 0.5-82 µg mol-1) depending on the hydrophilic to hydrophobic ratio of the polymer blocks and the amount of drug in the corona of the particle. The more stable micelle structures were investigated toward 143B human osteosarcoma cells, showing an enhanced cytotoxicity and cellular uptake compared to the free drug PENAO (IC50 (PENAO) = 2.7 ± 0.3 µM; IC50 (micelle M4) = 0.8 ± 0.02 µM). Furthermore, PENAOs arsonous acid residue remains active when incorporated into a polymer matrix and conjugates to small mono and closely spaced dithiols and is able to actively target the mitochondria, which is PENAO's main target to introduce growth inhibition in cancer cells. As a result, no cleavable linker between drug and polymer was necessary for the delivery of PENAO to osteosarcoma cells. These findings provide a rationale for in vivo studies of micelle M4 versus PENAO in an osteosarcoma animal model.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Arsenicais/química , Arsenicais/farmacologia , Nanopartículas/química , Polímeros/química , Polímeros/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Portadores de Fármacos/química , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Osteossarcoma/tratamento farmacológico , Osteossarcoma/patologia , Polimerização , Compostos de Sulfidrila/química
11.
Int J Mol Sci ; 18(6)2017 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-28556791

RESUMO

Abstract: Previous studies have shown that total epidermal growth factor receptor (EGFR) protein is highly expressed in soft tissue sarcoma (STS). We aimed to investigate the significance of phosphorylated-EGFR (pEGFR) and its activated-downstream signal transducers in STS tissue samples. A tissue microarray comprising 87 STS samples was assessed for total EGFR, pEGFR and its phosphorylated signal transducers and expression was correlated with clinicopathlogical parameters including patient outcome. Although the expression of total EGFR was significantly associated with adverse STS histologic grade (p = 0.004) and clinical stage (p = 0.012) similar to pEGFR, phosphorylated protein kinase B (pAkt) and phosphorylated extracellular signal regulated kinase (pERK), it is not a prognostic factor for survival. By contrast, the expression of pEGFR is an independent factor for cancer specific survival, while pERK is an independent prognostic factor for both overall and cancer specific survival in STS (p < 0.05, Cox proportional hazard model and log-rank test) in addition to the recognised factors of tumour grade and clinical stage. pERK and pEGFR are new independent prognostic factors for overall and/or cancer specific survival in STS. The expression of EGFR/pEGFR, and their associated downstream signal transducers, was associated with STS progression, suggesting that EGFR downstream signalling pathways may jointly support STS cell survival.


Assuntos
Receptores ErbB/metabolismo , Sarcoma/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Receptores ErbB/genética , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Fosforilação/genética , Fosforilação/fisiologia , Prognóstico , Sarcoma/genética , Sarcoma/patologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Adulto Jovem
13.
J Endovasc Ther ; 23(2): 275-84, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26839124

RESUMO

PURPOSE: To evaluate and characterize debris retrieved from the cerebral embolic protection devices (EPDs) used during carotid artery stenting (CAS) and compare debris size, volume, tissue types, cellular composition, and protein biomarker expression in symptomatic and asymptomatic patients. METHODS: Distal protection filters were retrieved from 22 consecutive patients (mean age 71.6 years, range 52-85; 16 men) undergoing elective CAS between July 2012 and February 2014 for >70% internal carotid artery stenosis (mean 85.4% ± 10.3%). Six patients were symptomatic. The debris within each EPD was visually characterized using stereomicroscopy and then processed for histology and immunohistochemistry. Biomarkers were immunohistochemically measured to evaluate plaque stability [matrix metalloproteinase-9 (MMP-9)], inflammation [glycoprotein CD68 and interleukin-6 (IL-6)], or phenotype [smooth muscle (SM)-actin and type IV collagen]. The immunohistochemical results were measured using semiquantitative grading criteria based on both staining intensity and distribution in the samples. RESULTS: Macroscopic debris was visible in 5/22 EPDs; 3 of the 5 filters came from symptomatic patients. Microscopic debris was detected in all filters and ranged in size from 0.01 to 8.57 mm(2). Debris consisted of calcified, fibrous, and necrotic tissue, as well as fibrin and foam cells with no significant difference between the symptomatic and asymptomatic groups. There was no association between the degree or type of embolic material and stenosis severity, carotid tortuosity, calcium grade, soft plaque, or arch type. Symptomatic patients had a larger volume of debris (8.24 vs 0.58 mm(3), p<0.01), mean particle size (1.30 vs 0.32 mm(2), p<0.001), and expression of biomarkers IL-6 (2.17 vs 0.81, p<0.05), CD68 (2.00 vs 0.38, p<0.01), SM-actin (1.00 vs 0.25, p=0.055), type IV collagen (1.17 vs 0.25,p=0.082), and MMP-9 (1.00 vs 0.06, p<0.05). CONCLUSION: Histological analysis revealed particulate embolization in all EPDs used during CAS. Symptomatic patients had a larger volume of embolic debris, mean particle size, and the biomarkers associated with inflammation, necrotic core, and diminished fibrous cap.


Assuntos
Artéria Carótida Interna/química , Artéria Carótida Interna/patologia , Estenose das Carótidas/terapia , Dispositivos de Proteção Embólica , Procedimentos Endovasculares/instrumentação , Imuno-Histoquímica , Microscopia/métodos , Placa Aterosclerótica , Stents , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Artéria Carótida Interna/diagnóstico por imagem , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/metabolismo , Estenose das Carótidas/patologia , Angiografia por Tomografia Computadorizada , Procedimentos Endovasculares/efeitos adversos , Feminino , Fibrose , Humanos , Masculino , Pessoa de Meia-Idade , Necrose , Valor Preditivo dos Testes , Estudos Prospectivos , Índice de Gravidade de Doença , Resultado do Tratamento , Ultrassonografia Doppler Dupla
14.
J Endovasc Ther ; 22(4): 473-81, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26012571

RESUMO

PURPOSE: To evaluate the effect of a shift to a primary endovascular revascularization (ER) strategy for patients presenting with critical limb ischemia (CLI) after a change in staff at our center in 2008 altered our revascularization strategy. METHODS: Between 2004 and 2012, 344 critically ischemic limbs were treated in 279 patients (mean age 74.0±11.4 years; 179 men) during 546 separate hospital admissions. Limbs were analyzed according to (1) their principal revascularization strategy and (2) their date of presentation [early (2004-2008) or late (2008-2012)]. RESULTS: Compared with the open revascularization (OR) and no revascularization (NR) groups, the ER group had an increased freedom from major amputation (92.3% vs 80.0% OR vs 69.3% NR, p<0.001), reduced hospital stay (15.2 vs OR 31.6 vs NR 25.9 days, p<0.001), intensive care unit (ICU) stay (2.3 vs OR 23.7 vs NR 7.2 hours, p=0.033), and operating time for ER vs OR (157.9 vs 316.8 minutes, respectively; p<0.0001). There was also a significant decrease in limbs requiring minor amputations (23.2% vs OR 29.3% vs NR 37.6%, p=0.041) and mean number of admissions/limb compared to OR (1.5 vs OR 1.9 vs NR 1.5, p=0.007). The late era saw the treatment of a larger number of limbs (223 vs 121) compared with the earlier time period. This institutional shift resulted in increased freedom from major amputation (87.4% vs 74.4%, p<0.01), reduced ICU stay (3.45 vs 16.98 hours, p<0.01), and shorter length of stay (20.9 vs 31.5 days, p<0.01) between the 2 eras, respectively. CONCLUSION: A shift to an endovascular-first treatment strategy is associated with fewer major amputations and shorter length of stay.


Assuntos
Procedimentos Endovasculares , Isquemia/cirurgia , Salvamento de Membro , Extremidade Inferior/irrigação sanguínea , Procedimentos Cirúrgicos Vasculares , Adulto , Idoso , Idoso de 80 Anos ou mais , Amputação Cirúrgica/estatística & dados numéricos , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
15.
J Endovasc Ther ; 21(2): 230-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24754282

RESUMO

PURPOSE: To investigate the corrosion resistance properties of 5 commercially available nitinol stents used to treat peripheral artery disease and compare their surface quality, elemental composition, and geometrical design. METHODS: Samples of 5 different designs of nitinol peripheral stents [LifeStent (n=4), Philon (n=6), Epic (n=6), S.M.A.R.T. Control (n=7), and Complete SE (n=7)] were examined using stereomicroscopy, environmental scanning electron microscopy, and x-ray photoelectron spectroscopy. Corrosion resistance testing was performed in accordance with ASTM International Standard F2129-08. RESULTS: Thirteen (43%) of 30 stents corroded during this experiment. Stent fracture was observed in 12 (92%) of these corroded stents. Mean breakdown potentials ranged from 517 to 835 mV (vs. Ag/AgCl) for the Philon, Complete SE, S.M.A.R.T. Control, Epic, and LifeStent models from lowest to highest. A statistically significant difference in breakdown potential was observed between the LifeStent vs. Philon stents (835 vs. 517 mV, p=0.01) and Epic vs. Philon stents (833 vs. 517 mV, p=0.03). Stents with lower breakdown potential and relative breakdown potentials were associated with a higher fracture frequency (Spearman correlation coefficient -0.44, p=0.015 and -0.869, p<0.01, respectively). CONCLUSION: In this in vitro study, corrosion led independently to stent fracture. There is a significant association between lower mean breakdown/relative breakdown potentials and stent fracture.


Assuntos
Ligas , Procedimentos Endovasculares/instrumentação , Doença Arterial Periférica/terapia , Desenho de Prótese , Falha de Prótese , Stents , Corrosão , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Propriedades de Superfície
16.
Eur J Orthop Surg Traumatol ; 24(5): 655-61, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23708975

RESUMO

BACKGROUND: Demineralized bone matrix (DBM) allografts are widely used in orthopaedic clinics. However, the biological impact on its osteoinductivity after its sterilization process by gamma irradiation is not well studied. Furthermore, little is known about the relationship between residual calcium levels on osteoinductivity. HYPOTHESIS: We hypothesize that low-dose gamma irradiation retains the osteoinducitivity properties of DBM and causes ectopic bone formation. MATERIALS AND METHODS: A randomised animal trial was performed to compare tissue and molecular responses of low-dose (11 kGy) gamma irradiated and non-irradiated human DBM at 6 weeks post-intramuscular implantation using an athymic rat model. In addition, we correlated residual calcium levels and bone formation in gamma irradiated DBM. RESULTS: A modified haematoxylin and eosin stain identified ectopic bony capsules at all implanted sites with no significant difference on the amount of new bone formed between the groups. Statistically significantly lower ratio of alkaline phosphatase expression over tartrate-resistant acid phosphatase and/or cathepsin K expressions was found between the groups. DISCUSSION: This study found that low-dose gamma irradiated DBM, which provides a sterility assurance level of 10(-6) for bone allografts, retained osteoinductivity but exhibited significantly enhanced osteoclastic activity. Furthermore, this is the first study to find a positive correlation between residual calcium levels and bone formation in gamma irradiated DBM.


Assuntos
Matriz Óssea/efeitos da radiação , Raios gama , Osteoclastos/efeitos da radiação , Fosfatase Alcalina/metabolismo , Animais , Matriz Óssea/metabolismo , Transplante Ósseo/métodos , Cálcio/metabolismo , Catepsina K/metabolismo , Xenoenxertos/metabolismo , Xenoenxertos/efeitos da radiação , Humanos , Imuno-Histoquímica , Masculino , Osteoclastos/metabolismo , Distribuição Aleatória , Ratos , Transplante Heterólogo
17.
J Colloid Interface Sci ; 670: 174-181, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38761570

RESUMO

Interlayer intercalation engineering shows great feasibility to improve the structure stability of the layered oxides. Although high Zn-storage capability has been attained based on the pillar effect of multifarious intercalants, an in-depth understanding the synergistic effect of intercalated multiple metal ions is still in deficiency. Herein, alkali metal ion K+, alkaline earth metal ion Mg2+ and trivalent metal ion Al3+ are introduced into the VO interlayer of V2O5. Due to the different electronegativity and hydrated ion radius of K+, Mg2+ and Al3+, adjusting the relative proportions of these metal ions can achieve an appropriate interlayer spacing, stable layer structure and regular morphology, which facilitates the transport kinetics of Zn2+. Under the synergistic effect of pre-intercalated multi-metal ion, the optimal tri-metal ion intercalated hydrated V2O5 cathode exhibits a high specific capacity of 382.4 mAh g-1 at 0.5 A g-1, and long-term cycling stability with capacity retention of 86 % after 2000 cycles at the high current density of 10 A g-1. Ex-situ and kinetic characterizations reveal the fast charge transfer and reversible Zn2+ intercalation mechanism. The multi-ion engineering strategy provides an effective way to design desirable layered cathode materials for aqueous zinc-ion batteries.

18.
J Biomed Mater Res A ; 112(5): 754-769, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38084898

RESUMO

The therapeutic effectiveness of anticancer drugs, including nanomedicines, can be enhanced with active receptor-targeting strategies. Epidermal growth factor receptor (EGFR) is an important cancer biomarker, constitutively expressed in sarcoma patients of different histological types. The present work reports materials and in vitro biomedical analyses of silanized (passive delivery) and/or EGF-functionalized (active delivery) ceria nanorods exhibiting highly defective catalytically active surfaces. The EGFR-targeting efficiency of nanoceria was confirmed by receptor-binding studies. Increased cytotoxicity and reactive oxygen species (ROS) production were observed for EGF-functionalized nanoceria owing to enhanced cellular uptake by HT-1080 fibrosarcoma cells. The uptake was confirmed by TEM and confocal microscopy. Silanized nanoceria demonstrated negligible/minimal cytotoxicity toward healthy MRC-5 cells at 24 and 48 h, whereas this was significant at 72 h owing to a nanoceria accumulation effect. In contrast, considerable cytotoxicity toward the cancer cells was exhibited at all three times points. The ROS generation and associated cytotoxicity were moderated by the equilibrium between catalysis by ceria, generation of cell debris, and blockage of active sites. EGFR-targeting is shown to enhance the uptake levels of nanoceria by cancer cells, subsequently enhancing the overall anticancer activity and therapeutic performance of ceria.


Assuntos
Cério , Nanopartículas , Humanos , Espécies Reativas de Oxigênio/metabolismo , Fator de Crescimento Epidérmico , Nanopartículas/química , Receptores ErbB , Cério/farmacologia , Cério/química
19.
J Colloid Interface Sci ; 664: 607-616, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38490036

RESUMO

Expanded graphite (EG) stands out as a promising material for the negative electrode in potassium-ion batteries. However, its full potential is hindered by the limited diffusion pathway and storage sites for potassium ions, restricting the improvement of its electrochemical performance. To overcome this challenge, defect engineering emerges as a highly effective strategy to enhance the adsorption and reaction kinetics of potassium ions on electrode materials. This study delves into the specific effectiveness of defects in facilitating potassium storage, exploring the impact of defect-rich structures on dynamic processes. Employing ball milling, we introduce surface defects in EG, uncovering unique effects on its electrochemical behavior. These defects exhibit a remarkable ability to adsorb a significant quantity of potassium ions, facilitating the subsequent intercalation of potassium ions into the graphite structure. Consequently, this process leads to a higher potassium voltage. Furthermore, the generation of a diluted stage compound is more pronounced under high voltage conditions, promoting the progression of multiple stage reactions. Consequently, the EG sample post-ball milling demonstrates a notable capacity of 286.2 mAh g-1 at a current density of 25 mA g-1, showcasing an outstanding rate capability that surpasses that of pristine EG. This research not only highlights the efficacy of defect engineering in carbon materials but also provides unique insights into the specific manifestations of defects on dynamic processes, contributing to the advancement of potassium-ion battery technology.

20.
Adv Mater ; 36(14): e2308927, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38174582

RESUMO

After application in electric vehicles, spent LiFePO4 (LFP) batteries are typically decommissioned. Traditional recycling methods face economic and environmental constraints. Therefore, direct regeneration has emerged as a promising alternative. However, irreversible phase changes can significantly hinder the efficiency of the regeneration process owing to structural degradation. Moreover, improper storage and treatment practices can lead to metamorphism, further complicating the regeneration process. In this study, a sustainable recovery method is proposed for the electrochemical repair of LFP batteries. A ligand-chain Zn-complex (ZnDEA) is utilized as a structural regulator, with its ─NH─ group alternatingly facilitating the binding of preferential transition metal ions (Fe3+ during charging and Zn2+ during discharging). This dynamic coordination ability helps to modulate volume changes within the recovered LFP framework. Consequently, the recovered LFP framework can store more Li-ions, enhance phase transition reversibility between LFP and FePO4 (FP), modify the initial Coulombic efficiency, and reduce polarization voltage differences. The recovered LFP cells exhibit excellent capacity retention of 96.30% after 1500 cycles at 2 C. The ligand chain repair mechanism promotes structural evolution to facilitate ion migration, providing valuable insights into the targeted ion compensation for environmentally friendly recycling in practical applications.

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