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1.
Nano Lett ; 24(30): 9178-9185, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39017609

RESUMO

Lithium (Li) dendritic growth and huge volume expansion seriously hamper Li-metal anode development. Herein, we design a lightweight 3D Li-ion-affinity host enabled by silver (Ag) nanoparticles fully decorating a porous melamine sponge (Ag@PMS) for dendrite-free and high-areal-capacity Li anodes. The compact Ag nanoparticles provide abundant preferred nucleation sites and give the host strong conductivity. Moreover, the high specific surface area and polar groups of the elastic, porous melamine sponge enhance the Li-ion diffusion kinetics, prompting homogeneity of Li deposition and stripping. As expected, the integrated 3D Ag@PMS-Li anode delivered a remarkable electrochemical performance, with a Coulombic efficiency (CE) of 97.14% after 450 cycles at 1 mA cm-2. The symmetric cell showed an ultralong lifespan of 3400 h at 1 mA cm-2 for 1 mAh cm-2. This study provides a facile and cost-effective strategy to design an advanced 3D framework for the preparation of a stable dendrite-free Li metal anode.

2.
Altern Ther Health Med ; 30(1): 160-166, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37773668

RESUMO

Objective: To investigate the long-term safety and efficacy of autologous peripheral blood stem cell transplantation (APBSCT) in treating decompensated hepatitis B cirrhosis. Methods: In this study, a retrospective analysis was conducted on a cohort of 84 patients diagnosed with decompensated hepatitis B cirrhosis between January 2011 and December 2012. The patients were categorized into two groups based on their treatment approach: the transplantation group, consisting of 34 cases who received APBSCT in addition to medical treatment, and the comprehensive medical treatment (CMT) group, comprising 50 cases who solely received CMT. EPI Data software was used for data input and verification. Survival curves were drawn by Kaplan-Meier method and analyzed by log-rank test. Paired t test and independent sample t test were used for intra-group and inter-group mean comparison of measurement data, respectively. The Mann-Whitney U test is used for non-normally distributed data. Results: After the ten-year follow-up period, it was found that overall survival (OS) in the transplantation group was markedly higher than that in the CMT (56% vs. 16%, P < .001). Albumin (ALB), prothrombin time (PT), and indocyanine green retention at 15 min (ICG R15) were significantly improved in sequence at 4 to 12 weeks of early treatment in APBSCT group; subsequently, the Acoustic radiation force impulse (ARFI) index and spleen length significantly decreased at 48 weeks. Compared with the CMT group, ALB and PT levels in the APBSCT group continued to recover and eventually stabilize at normal or low-risk levels at subsequent follow-ups up to 8 years. The ten-year prevalence of hepatocellular carcinoma (HCC) in the APBSCT group was markedly lower than that in the CMT group (26% vs. 62%; P = .025). Moreover, APBSCT significantly reduced ascites (χ2 = 6.997, P = .041) and was not associated with any significant adverse events during APBSCT. Based on clinical evidence, APBSCT is a safe and effective treatment for decompensated hepatitis B cirrhosis, resulting in a favorable long-term prognosis with no significant adverse events. Conclusions: APBSCT is a relatively safe and effective treatment for decompensated hepatitis B cirrhosis.


Assuntos
Carcinoma Hepatocelular , Hepatite B , Neoplasias Hepáticas , Transplante de Células-Tronco de Sangue Periférico , Humanos , Transplante de Células-Tronco de Sangue Periférico/métodos , Estudos Retrospectivos , Hepatite B/complicações , Hepatite B/diagnóstico , Cirrose Hepática/terapia , Cirrose Hepática/diagnóstico
3.
Artigo em Inglês | MEDLINE | ID: mdl-37944965

RESUMO

Objective: In recent years, stem cell transplantation (SCT) has been applied to the clinical treatment of patients with cirrhosis. The specialist clinic of the SCT clinic provides regular and effective interventions for cirrhosis, helping to improve patient management and compliance. The aim of this study was to determine the efficacy and safety of SCT in the treatment of cirrhosis. Methods: This systematic review adhered to the guidelines outlined in the PRISMA statement. The National Library of Medicin (MEDLINE), Excerpt Medica Database (EMBASE), Cochrane Central Register of Controlled Trials (CENTRAL), and Clinical Trials.gov databases were searched to screen liver cirrhosis-related articles with stem cell therapy from 2000 to 2022. The articles were then filtered and extracted for clinical outcomes including MELD score, Child-Pugh score, platelets, creatinine, bilirubin, albumin, international normalized ratio (INR), alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyl transferase (GGT), alkaline phosphatase (ALP), α fetoprotein (AFP), prothrombin time (PT). The data were normalized and analyzed using the standardized mean difference (SMD) and 95% confidence interval (CI). Results: A total of 1209 articles were searched, and from these, ten studies were selected for analysis regarding the association between SCT and the clinical outcomes of liver cirrhosis. The findings revealed that SCT therapy, in comparison to conventional treatment, resulted in a reduction in MELD score and INR after 1 month, a decrease in Child-Pugh score at 3 months, an increase in platelet count at 3 months, and an elevation in ALB levels after 1 month. However, no significant beneficial effects were observed on creatinine, bilirubin, PT, ALT, AST, GGT, ALP, and ASP levels. Conclusion: This study suggested that SCT therapy could elevate the ALB levels and alleviate the MELD score and INR, short-term decreasing the Chile-Pugh score and increasing the platelet levels. It could be a potential therapeutic alternative for patients with cirrhosis.

4.
Small ; 18(15): e2200114, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35218161

RESUMO

Piezoelectric pressure sensors are important for applications in robotics, artificial intelligence, communication devices, etc. The hyperboloid is theoretically predicted to be an unusual 3D structure that allows concerted piezoelectric enhancement owing to its synergistic effects of geometrical stress confinement and stress concentration, but has not been experimentally fulfilled due to a lack of efficient architecting techniques. In this work, a 3D hyperboloidal arrayed self-polarized PVDF piezoelectric energy harvester (PEH) is successfully fabricated by incorporating electrohydrodynamic (EHD) pulling technology into fused deposition modeling (FDM) 3D printing. This strategy not only simplifies the layer-by-layer constructing procedure for arrays, but simultaneously realizes a self-polarized and high ß-phase (92%) PVDF PEH in a single electric-pulling step, saving posttreatment such as poling and removing excessive additives. Such a PEH delivers a significantly enhanced piezoelectric potential which is around 8 times that of a 2D flat film sensor. Moreover, this PEH featuring excellent linearity within a wide pressure regime, enables the sensing of human activities in a relatively large force range, which is otherwise difficult for traditional film sensors to differentiate. This work demonstrates a potential roadmap to advanced piezoelectric sensors exploiting unusual 3D structures enabled by the unique EHD pulling coupled 3D printing technique.


Assuntos
Inteligência Artificial , Polivinil , Eletricidade , Polímeros de Fluorcarboneto , Humanos , Polivinil/química , Impressão Tridimensional
5.
Angew Chem Int Ed Engl ; 57(40): 13012-13014, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30183117

RESUMO

Follow the yellow brick road: Functional polymers can be prepared directly at room temperature from elemental sulfur by the Willgerodt-Kindler reaction. This method opens a new synthetic door for the synthesis and application of polythioamides and polythioureas.

6.
Biomacromolecules ; 15(8): 3197-205, 2014 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-25019415

RESUMO

Activated ester polymers, pioneered by Ferruti and Ringsdorf in the 1970s, are attractive polymeric materials because they can easily be converted into functional polymers by reacting with amine nucleophiles. In the present study, methyl salicylate acrylate, salicyl acrylate, and tert-butyl salicylate acrylate monomers were polymerized yielding three novel reactive precursors suitable for the postpolymerization modification with primary and secondary amines. The reactivities of poly(pentafluorophenyl acrylate), poly(methyl salicylate acrylic ester), and poly(salicyl acrylate) toward amines were compared by kinetic studies and revealed the practical applicability of salicylic acid based derivatives for efficient postpolymerization modifications. In addition, in vitro cytotoxicity of water-soluble leaving groups, pentafluorophenol and salicylic acid, as well as water-soluble polymers containing the respective activated ester groups were investigated using HeLa cells. In short, compared to the frequently used poly(pentafluorophenyl acrylate), poly(salicyl acrylate) activated ester feature a lower reactivity, but exhibit less cytotoxicity. In this respect, poly(salicyl acrylate) as reactive precursor polymers may become alternative routes for the synthesis of functional polyacrylamides when it comes to advanced applications in vivo.


Assuntos
Materiais Biocompatíveis/química , Ésteres/química , Polímeros/química , Acrilatos/química , Células HeLa , Humanos , Substâncias Macromoleculares/química , Polimerização , Água/química
7.
Acta Chim Slov ; 61(4): 786-91, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25551718

RESUMO

Two new pi-conjugated pyridine-based tetrathiafulvalene derivatives, 2-(2- (4,5-bis(methylthio)-1,3-dithiol-2-ylidene)-6-phenyl-[1,3]dithiolo[4,5-b][1,4]dithiin-5-yl)pyridine (2a) and 3-(2-(4,5-bis(methylthio)-1,3-dithiol-2-ylidene)-6-(pyridin-2-yl) -[1,3]dithiolo[4,5-b][1,4]dithiin-5-yl)quinoline (2b), have been synthesized and characterized by 1H NMR, elemental analysis and mass spectroscopies. The compound 2a has also been studied by X-ray crystallography and theoretical calculations using density functional theory (DFT) framework with B3LYP/6-311+G(d,p) level of theory. Its crystal structure is triclinic system, space group P1-. The unit cell dimensions are: a = 8.813(3) Å, b = 11.082(3) Å, c = 12.620(4) Å, alfa = 88.805(5)°, beta = 80.440(5)°, gama = 75.680(5)°, V = 1177.3(6) Å3, Z = 2. The molecule exhibits one classical C-H···N intermolecular hydrogen bonds, two kinds of short intermolecular S···S interactions and two types of C-H···pi supramolecular interactions.

8.
J Clin Sleep Med ; 20(9): 1435-1444, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38648118

RESUMO

STUDY OBJECTIVES: This study investigated the impact of automatic positive airway pressure (APAP) therapy on vascular behavior and its potential to lower cardiovascular risk in patients with obstructive sleep apnea (OSA), as well as differentiating APAP therapy heterogeneity. METHODS: All participants were diagnosed with OSA by portable monitoring, and pulse wave parameters and cardiac risk composite parameter index were obtained by photoplethysmography before and after APAP. Clustering analysis of pulse wave parameters before APAP in the high-risk population was performed using k-means clustering. Linear regression was used to assess the associations of changes in cardiac risk composite parameter index and pulse wave parameters with clinical characteristics. RESULTS: Eighty-two patients with OSA underwent APAP therapy. The cardiac risk composite parameter index after APAP was significantly lower than before APAP (0.38 ± 0.33 and 0.58 ± 0.31, respectively; P < .001). All pulse wave parameters (except irregular pulse) were significantly different (P < .001) in patients with OSA and in the high-risk responders group after vs before APAP. The differences in pulse wave parameters after vs before APAP were not significant in the high-risk nonresponders group, except for the difference between the pulse rate acceleration index and the oxygen saturation index and pulse rate variability. Four clusters were obtained from the clustering analysis of pulse wave parameters before APAP in the high-risk responders group. CONCLUSIONS: APAP reduces the cardiac risk composite parameter index in patients with OSA by altering vascular behavior. Overnight photoplethysmography monitoring of pulse wave parameters can be used to assess whether patients with OSA will benefit from APAP. CITATION: Zhu W, Xiang L, Cao L, Tian Y, Li W, He L. Evaluating the impact of automatic positive airway pressure therapy on cardiovascular risk index and vascular behavior in patients with obstructive sleep apnea: a study on heterogeneity in the therapeutic response. J Clin Sleep Med. 2024;20(9):1435-1444.


Assuntos
Doenças Cardiovasculares , Pressão Positiva Contínua nas Vias Aéreas , Apneia Obstrutiva do Sono , Humanos , Apneia Obstrutiva do Sono/terapia , Apneia Obstrutiva do Sono/fisiopatologia , Apneia Obstrutiva do Sono/complicações , Masculino , Feminino , Pessoa de Meia-Idade , Pressão Positiva Contínua nas Vias Aéreas/métodos , Doenças Cardiovasculares/fisiopatologia , Fatores de Risco de Doenças Cardíacas , Fotopletismografia/métodos , Análise de Onda de Pulso/métodos , Adulto , Resultado do Tratamento , Polissonografia/métodos
9.
Small Methods ; : e2301707, 2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38343185

RESUMO

For polyvinylidene fluoride (PVDF) based piezoelectric composites, epitaxial growth of ZnO nanorods (ZnO-nr) piezoceramic layer on PVDF is an effective way to improve their piezoelectric performance. However, the crystal nucleus of ZnO featuring polar surfaces that cannot be directly attached to hydrophobic PVDF with low surface energy. Herein, direct ink writing (DIW) 3D printing is employed for the first time to create ß-PVDF reservoirs with significantly enhanced surface energy, facilitating the attachment and epitaxial growth of ZnO-nr. The printed ß-PVDF reservoirs designed with programmed macro-pores and abundant inner micropores, enable a higher loading of ZnO-nr by more than one magnitude, thereby boosting the electro-mechanical response. The resulting PVDF/ZnO core-shell piezoelectric energy harvester (PEH) delivers an output voltage of 33.2 V, as well as an unprecedentedly high relative output voltage of 2.76 V/wt.%, which is 2.63 times that of the state-of-the-art 3D-printed PVDF/piezoceramics PEHs. Furthermore, it can differentiate subtle human motions whereas hybrid PEHs cannot distinct. This work demonstrates that the DIW 3D printing approach offers a simple and convenient design idea for creating high performance PEHs.

10.
ACS Appl Mater Interfaces ; 16(13): 16880-16892, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38506556

RESUMO

To meet the demands of challenging usage scenarios, there is an increasing need for flexible electronic skins that can operate properly not only in terrestrial environments but also extend to complex aquatic conditions. In this study, we develop an elastomer by incorporating dynamic urea bonds and hydrogen bonds into the polydimethylsiloxane backbone, which exhibits excellent autonomous self-healing and reversible adhesive performance in both dry and wet environments. A multifunctional flexible sensor with excellent sensing stability, amphibious self-healing capacity, and amphibious self-adhesive performance is fabricated through solvent-free 3D printing. The sensor has a high sensing sensitivity (GF = 45.1) and a low strain response threshold (0.25%) and can be used to detect small human movements and physiological activities, such as muscle movement, joint movement, respiration, and heartbeat. The wireless wearable sensing system assembled by coupling this device with a bluetooth transmission system is suitable for monitoring strenuous human movement in amphibious environments, such as playing basketball, cycling, running (terrestrial environments), and swimming (aquatic environments). The design strategy provides insights into enhancing the self-healing and self-adhesive properties of soft materials and promises a prospective avenue for fabricating flexible electronic skin that can work properly in amphibious environments.


Assuntos
Elastômeros , Dispositivos Eletrônicos Vestíveis , Humanos , Elastômeros/química , Cimentos de Resina , Adesivos , Estudos Prospectivos , Eletrônica , Impressão Tridimensional
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