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Silicon monoxide (SiO) has attracted considerable interest as anode material for lithium-ion batteries (LIBs). However, their poor initial Coulombic efficiency (ICE) and conductivity limit large-scale applications. Prelithiation and carbon-coating are common and effective strategies in industry for enhancing the electrochemical performance of SiO. However, the involved heat-treatment processes inevitably lead to coarsening of active silicon phases, posing a significant challenge in industrial applications. Herein, the differences in microstructures and electrochemical performances between prelithiated SiO with a pre-coated carbon layer (SiO@C@PLi) and SiO subjected to carbon-coating after prelithiation (SiO@PLi@C) are investigated. A preliminary carbon layer on the surface of SiO before prelithiation is found that can suppress active Si phase coarsening effectively and regulate the post-prelithiation phase content. The strategic optimization of the sequence where prelithiation and carbon-coating processes of SiO exert a critical influence on its regulation of microstructure and electrochemical performances. As a result, SiO@C@PLi exhibits a higher ICE of 88.0%, better cycling performance and lower electrode expansion than SiO@PLi@C. The pouch-type full-cell tests demonstrate that SiO@C@PLi/Graphite||NCM811 delivers a superior capacity retention of 91% after 500 cycles. This work provides invaluable insights into industrial productions of SiO anodes through optimizing the microstructure of SiO in prelithiation and carbon-coating processes.
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Silicon (Si) is one of the most promising anode materials for high-energy-density lithium-ion batteries. However, the huge volume expansion hinders its commercial application. Embedding amorphous Si nanoparticles in a porous carbon framework is an effective way to alleviate Si volume expansion, with the pore volume of the carbon substrates playing a pivotal role. This work demonstrates the impact of pore volume on the electrochemical performance of the silicon/carbon porous composites from two perspectives: 1) pore volume affects the loadings of Si particles; 2) pore volume affects the structural stability and mechanical properties. The smaller pore volume of the carbon substrate cannot support the high Si loadings, which results in forming a thick Si shell on the surface, thereby being detrimental to cycling stability and the diffusion of electrons and ions. On top of that, the carbon substrate with a larger pore volume has poor structural stability due to its fragility, which is also not conducive to realizing long cycle life and high rate performance. Achieving excellent electrochemical performances should match the proper pore volume with Si content. This study will provide important insights into the rational design of the silicon/carbon porous composites based on the pore volume of the carbon substrates.
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Silicon monoxide (SiO) has attracted growing attention as one of the most promising anodes for high-energy-density lithium-ion batteries (LIBs), benefiting from relatively low volume expansion and superior cycling performance compared to bare silicon (Si). However, the size of the SiO particle for commercial application remains uncertain. Besides, the materials and concepts developed on the laboratory level in half cells are quite different from what is necessary for practical operation in full cells. Herein, we investigate the electrochemical performance of SiO with different particle sizes between half cells and full cells. The SiO with larger particle size exhibits worse electrochemical performance in the half cell, whereas it demonstrates excellent cycling stability with a high capacity retention of 91.3% after 400 cycles in the full cell. The reasons for the differences in their electrochemical performance between half cells and full cells are further explored in detail. The SiO with larger particle size possessing superior electrochemical performance in full cells benefits from consuming less electrolyte and not being easier to aggregate. It indicates that the SiO with larger particle size is recommended for commercial application and part of the information provided from half cells may not be advocated to predict the cycling performances of the anode materials. The analysis based on the electrochemical performance of the SiO between half cells and full cells gives fundamental insight into further Si-based anode research.
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Novel functions and involvement of circFARSA have not been reported in pancreatic cancer; in addition, its inhibitor screening has not yet been conducted. The purpose of this study was to (1) verify circFARSA as a novel anti-cancer target for pancreatic cancer and (2) to prepare a novel anti-pancreatic cancer agent targeting circFARSA. In this study, we designed and synthesized a small interfering RNA (siRNA, named siRNA-circFARSA), which specifically inhibits circFARSA expression. Using liposomes and porous silicon nanoparticles (pSiNPs) as siRNA delivery system, we prepared liposome-siRNA-circFARSA and pSiNP-PEI-siRNA-circFARSA and investigated their anti-cancer mechanism by quantitative real-time PCR and western blotting. Cell proliferation curves and transwell migration assays were performed to investigate the effect of siRNAs proliferation and migration capabilities of cancer cells. Patient-derived tumor xenograft mouse models were used to investigate the anti-cancer effects in vivo. The data showed that both liposome-siRNA-circFARSA and pSiNP-PEI-siRNA-circFARSA (Si: 0.7 µg/mL) significantly inhibited the proliferation and migration of pancreatic cancer cells in vitro. However, the biological safety and in vivo anti-cancer effects of pSiNP-PEI-siRNA-circFARSA (Si: 22.4 µg/mL) were higher than those of liposome-siRNA-circFARSA. The results showed that siRNA-circFARSA could inhibit the expression of circFARSA and then BCL-2 protein expression, thereby leading to pancreatic cancer cell apoptosis after transportation into pancreatic cancer cells. Therefore, this study provides tools for pancreatic cancer treatment in the future, as it (1) verified circFARSA as a novel target for pancreatic cancer treatment, and (2) prepared a novel anti-pancreatic cancer agent (pSiNP-PEI-siRNA-circFARSA).
Asunto(s)
Nanopartículas/química , Neoplasias Pancreáticas/patología , ARN Circular/antagonistas & inhibidores , ARN Interferente Pequeño/farmacología , Silicio/química , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Silenciador del Gen , Humanos , Liposomas/química , Masculino , Ratones , Ratones Desnudos , ARN Interferente Pequeño/administración & dosificación , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Bio-functional cell scaffolds have great potential in the field of tissue regenerative medicine. In this work, a carbon nanotube (CNT) gel scaffold via specific pairing of functionalized nucleobases was developed for specifically targeted drug delivery and in vitro osteogenesis. The CNT gel scaffold with nano-fibrous architectures was established by Watson-Crick base pairing between thymine and adenine of low molecular weight heparin, respectively. As scaffold precursors, adenine and thymine functionalized heparin derivatives could additionally bind cell growth factors by the affinity interaction. The resulting nano-fibrous gel scaffolds showed excellent mechanical integrity and advanced electro-physiological functions. Potential application of the electrophysiological CNT gel scaffold in bone tissue engineering was confirmed by encapsulation of human adipose-derived stem cells (ASCs). Our results indicate that the electrically conductive networks formed by CNTs within the nano-fibrous framework are the key characteristics of cell scaffolds leading to improved ASC organization and differentiation by an extra electrical stimulus (ES). Specifically, ASCs cultured in bio-electrical gel scaffolds showed â¼4 times higher spontaneous osteogenesis in combination with bone morphogenetic protein 2 (BMP-2), compared to those cultured on pristine hydrogels. This electrophysiological CNT gel scaffold containing BMP-2 exhibited beneficial effects on ASC activity and osteogenetic differentiation, which suggested a promising future for local treatment of bone regeneration.
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For practical adipose regeneration, the challenge is to dynamically deliver the key adipogenic insulin-like growth factors in hydrogels to induce adipogenesis. In order to achieve dynamic release, smart hydrogels to sense the change in the blood glucose concentration is required when glucose concentration increases. In this study, a heparin-based hydrogel has been developed for use in dynamic delivery of heparin nanospheres containing insulin-like growth factor. The gel scaffold was facilely prepared in physiological conditions by the formation of boronate-maltose ester cross-links between boronate and maltose groups of heparin derivatives. Due to its intrinsic glucose-sensitivity, the exposure of gel scaffold to glucose induces maltose functionalized nanospheres dissociation off hydrogel network and thereby could dynamically move into the microenvironment. The potential of the hydrogel as a cell scaffold was demonstrated by encapsulation of human adipose-derived stem cells (ASCs) within the gel matrix in vitro. Cell culture showed that this dynamic hydrogel could support survival and proliferation of ASCs. This biocompatible coupling chemistry has the advantage that it introduces no potentially cytotoxic groups into injectable gel scaffolds formed and can create a more biomimetic microenvironment for drug and cell delivery, rendering them more suitable for potential in vivo biomedical applications. All these results indicate that this biocompatible gel scaffold can render the formulation of a therapeutically effective platform for diabetes treatment and adipose regeneration.
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Biopolímeros/química , Portadores de Fármacos/química , Hidrogeles/química , Factor I del Crecimiento Similar a la Insulina/farmacología , Nanosferas/química , Tejido Adiposo/química , Ácidos Borónicos/química , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Reactivos de Enlaces Cruzados/química , Composición de Medicamentos/métodos , Liberación de Fármacos , Glucosa/química , Humanos , Cinética , Maltosa/química , Células Madre Mesenquimatosas , Tamaño de la Partícula , Propiedades de Superficie , Ingeniería de Tejidos/métodos , Andamios del Tejido/químicaRESUMEN
BACKGROUND & OBJECTIVE: Intravesical instillation is an important adjuvant therapy on preventing postoperative recurrence of superficial bladder transitional cell carcinoma, but the recurrence rate is still high. This study was to evaluate the prophylactic effect of intravesical instillation of hydroxycamptothecin (HYD) plus bacillus Calmette-Guerin (BCG) on postoperative recurrence of bladder transitional cell cancer. METHODS: A total of 45 bladder cancer patients who underwent TURBT or partial cystectomy were divided into two groups: 24 patients in combination group received single intravesical instillation of HYD in Week 1 after operation and regular intravesical instillation of BCG since Week 2; 21 patients in BCG group received regular intravesical instillation of BCG since Week 1 after operation. All the patients were followed up for 24 months. RESULTS: Three patients had recurrence at 2, 10, and 12 months after operation individually in BCG group; no recurrence developed in combination group. The recurrence rate was significantly higher in BCG group than in combination group (14.28% vs. 0, P<0.05). No serious adverse events and complication developed in both groups. CONCLUSION: Early use of single intravesical instillation of HYD plus subsequent regular intravesical instillation of BCG is markedly effective for preventing postoperative recurrence of bladder transitional cell cancer, with few adverse events.
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Vacuna BCG/uso terapéutico , Camptotecina/análogos & derivados , Carcinoma de Células Transicionales/tratamiento farmacológico , Recurrencia Local de Neoplasia/prevención & control , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Adyuvantes Inmunológicos/administración & dosificación , Adyuvantes Inmunológicos/efectos adversos , Adyuvantes Inmunológicos/uso terapéutico , Administración Intravesical , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/efectos adversos , Antineoplásicos Fitogénicos/uso terapéutico , Vacuna BCG/administración & dosificación , Vacuna BCG/efectos adversos , Camptotecina/administración & dosificación , Camptotecina/efectos adversos , Camptotecina/uso terapéutico , Carcinoma de Células Transicionales/cirugía , Cistectomía , Femenino , Fiebre/inducido químicamente , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Vejiga Urinaria/cirugíaRESUMEN
OBJECTIVE: To investigate the information acquired through the four diagnostic methods of traditional Chinese medicine in patients with bronchial asthma, and to classify the syndrome types. METHODS: Four hundred and thirty patients with bronchial asthma were randomly investigated. The information acquired through the four diagnostic methods was recorded and the database was established by Amos software, and then the data were analyzed by confirmatory factor analysis (CFA). RESULTS: After analyzing the data with 4 factors, 5 factors and 6 factors, we found that the results of CFA with 6 factors were in accordance with clinical practical experience. CONCLUSION: According to the results of CFA with 6 factors and with the standard regression coefficient 0.4 as primary and secondary critical points, the syndromes in patients with bronchial asthma can be classified into 5 types, which are syndromes of cold fluid retained in lung, phlegm-heat obstructing lung, wind-phlegm blocking lung, qi deficiency of lung and kidney and qi deficiency of spleen.