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1.
Small Methods ; : e2400480, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38803307

RESUMO

Enhancing the output performance of triboelectric nanogenerators (TENGs) is essential for increasing their application in smart devices. Oxygen-vacancy-rich BiO2-x nanosheets (BiO2-x NSs) are advanced-engineered nanomaterials with excellent piezoelectric properties. Herein, a stretchable unsymmetrical BiO2-x NSs deposited-hydrogel made of polyacrylamide (PAM) as a multimodal TENG is rationally fabricated, and the performance of TENG can be tailored by controlling the BiO2-x NSs deposition amount and spatial distribution. The alteration of resistance caused by the Poisson effect of PAM/BiO2-x composite hydrogel (H-BiO2-x) can be used as a piezoresistive sensor, and the piezoelectricity of BiO2-x NSs can effectively enhance the density of transfer charge, thus improving the output performance of the H-BiO2-x-based TENG. In addition, the chemical cross-linking between the BiO2-x NSs and the PAM polymer chain allows the hydrogel electrode to have a higher tensile capacity (867%). Used for biomechanical motion signal detection, the sensors made of H-BiO2-x have high sensitivity (gauge factor = 6.93) and can discriminate a range of forces (0.1-5.0 N) at low frequencies (0.5-2.0 Hz). Finally, the prepared TENG can collect biological energy and convert it into electricity. Consequently, the improved TENG shows a good application prospect as multimodal biomechanical sensors by combining piezoresistive, piezoelectric, and triboelectric effects.

2.
Nano Lett ; 24(17): 5351-5360, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38634773

RESUMO

Ultrasensitive and reliable conductive hydrogels are significant in the construction of human-machine twinning systems. However, in extremely cold environments, freezing severely limits the application of hydrogel-based sensors. Herein, building on biomimetics, a zwitterionic hydrogel was elaborated for human-machine interaction employing multichemical bonding synergies and experimental signal analyses. The covalent bonds, hydrogen bonds, and electrostatic interactions construct a dense double network structure favorable for stress dispersion and hydrogen bond regeneration. In particular, zwitterions and ionic conductors maintained excellent strain response (99 ms) and electrical sensitivity (gauge factor = 14.52) in the dense hydrogel structure while immobilizing water molecules to enhance the weather resistance (-68 °C). Inspired by the high sensitivity, zwitterionic hydrogel-based strain sensors and remote-control gloves were designed by analyzing the experimental signals, demonstrating promising potential applications within specialized flexible materials and human-machine symbiotic systems.


Assuntos
Hidrogéis , Hidrogéis/química , Humanos , Dispositivos Eletrônicos Vestíveis , Congelamento , Ligação de Hidrogênio , Eletricidade Estática , Condutividade Elétrica
4.
Am J Kidney Dis ; 78(1): 19-27.e1, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33418016

RESUMO

RATIONALE & OBJECTIVE: Previous studies have illustrated the potential superiority of drug-coated balloons (DCBs) in maintaining patency after initial angioplasty for arteriovenous fistula (AVF) dysfunction due to stenosis. Our trial evaluated the efficacy and safety of DCBs for preventing fistula restenosis in Chinese hemodialysis patients. STUDY DESIGN: Multicenter, prospective, randomized, open-label, blinded end point, controlled trial. SETTINGS & PARTICIPANTS: A total of 161 hemodialysis patients with fistula dysfunction from 10 centers in China. INTERVENTION: Participants were randomized 1:1 to treatment with initial dilation followed by DCB angioplasty or conventional high-pressure balloon (HPB) angioplasty. OUTCOMES: The primary end point was target lesion primary patency defined as the target lesion intervention-free survival in conjunction with an ultrasonography-measured peak systolic velocity ratio (PSVR) ≤2.0 at 6 months. The secondary end points included 1) device, technical, clinical, and procedural success; 2) major adverse events; 3) degree of target lesion stenosis at 6 months; and 4) clinically driven target lesion and target shunt revascularization within 12 months. RESULTS: The percentage with target lesion primary patency as defined by a PSVR ≤2.0 was higher in the DCB group than in the control group (65% vs 37%, respectively; rate difference, 28% [95% CI, 13%-43%]; P <0.001) at 6 months. The target lesion and target shunt intervention-free survival of the DCB group were not superior to those of the control group at 6 months (P = 0.3 and P = 0.2, respectively) but were superior at 12 months (target lesion intervention-free survival: 73% for DCB vs 58% for control [P = 0.04]; target shunt intervention-free survival: 73% for DCB vs 57% for control [P = 0.04]). The average degree of target lesion stenoses at 6 months was not significantly different between the 2 groups (44% ± 16% for DCB vs 49% ± 18% for control; P = 0.09). There were no significant differences in major adverse events or in device, technical, clinical, or procedural success rates between the groups. LIMITATIONS: Small sample size; short follow-up period; procedural differences between the 2 groups such as unequal inflation times and balloon lengths. CONCLUSIONS: Compared to conventional HPB angioplasty, DCB treatment achieved superior primary patency defined using PSVR measured at 6 months and superior intervention-free survival of both the target lesion and the target shunt at 12 months without evidence of greater adverse events. FUNDING: Funded by ZhuHai Cardionovum Medical Device Co., Ltd. TRIAL REGISTRATION: Registered at ClinicalTrials.gov with study number NCT02962141.


Assuntos
Angioplastia com Balão , Derivação Arteriovenosa Cirúrgica , Materiais Revestidos Biocompatíveis , Paclitaxel/administração & dosagem , Complicações Pós-Operatórias/terapia , Diálise Renal , Grau de Desobstrução Vascular , Adulto , Idoso , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Constrição Patológica/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
5.
J Pharm Pharmacol ; 64(2): 277-82, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22221104

RESUMO

OBJECTIVES: This study investigated whether spinosin potentiates pentobarbital-induced loss of righting reflex (LORR) in mice via 5-HT(1A) receptors. METHODS: Our primary endpoint for sedation was LORR. In addition, the basal rectal temperature was measured. KEY FINDINGS: The results demonstrated that the 5-HT(1A) agonist 8-OH-DPAT (s.c.) induced reductions in duration of LORR at 0.1, 0.5 and 1.0 mg/kg (P < 0.01), and prolongation of LORR latency at 0.5 and 1.0 mg/kg (s.c., P < 0.01) in pentobarbital (45 mg/kg, i.p.)-treated mice. This effect of 8-OH-DPAT was antagonized either by 5-HT(1A) antagonist p-MPPI (5 mg/kg, i.p.) or by spinosin (15 mg/kg, i.g.) with significance, respectively. Co-administration of spinosin and p-MPPI both at ineffective doses (spinosin at 5.0 mg/kg, i.g. and p-MPPI at 1.0 mg/kg, i.p.) showed significant augmentative effects in reducing latency to LORR, and increasing LORR duration (P < 0.01) in pentobarbital-treated mice. On the other hand, spinosin inhibited 8-OH-DPAT-induced hypothermia, which has been generally attributed to the activation of somatodendritic 5-HT(1A) autoreceptors in mice. CONCLUSIONS: Based on our previous results and the present data, it should be presumed that presynaptic 5-HT(1A) autoreceptor mechanisms may be involved in the inhibitory effect of spinosin on 8-OH-DPAT-induced hypothermia and also in the potentiating effect of spinosin on pentobarbital-induced LORR in mice.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Flavonoides/farmacologia , Pentobarbital/toxicidade , Receptor 5-HT1A de Serotonina/metabolismo , Receptores Pré-Sinápticos/efeitos dos fármacos , Reflexo de Endireitamento/efeitos dos fármacos , 8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , Administração Oral , Aminopiridinas/farmacologia , Análise de Variância , Animais , Hipotermia/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos ICR , Piperazinas/farmacologia , Agonistas do Receptor de Serotonina/farmacologia
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