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1.
Heliyon ; 10(7): e29160, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38617915

RESUMEN

Dapagliflozin (DAPA) has been demonstrated to reduce cardiovascular mortality and heart failure hospitalization rates in diabetic patients. However, the mechanism underlying its cardio-protective effect in non-diabetic patients remains unclear. Our study aimed to explore the cardio-protective impact of DAPA on myocardial infarction in non-diabetic mice. We induced myocardial infarction in C57BL/6 mice by ligating the descending branch of the left coronary artery. After surgery, the animals were randomly treated with either saline or DAPA. We employed echocardiography, Western blot analysis, and tissue staining to assess post-infarction myocardial injury. Additionally, we investigated the mechanism of action through cell experiments. Compared to the myocardial infarction group, DAPA treatment significantly attenuated ventricular remodeling and improved cardiac function. By mitigating myocardial oxidative stress and apoptosis, DAPA may activate the AMPKα signaling pathway, thereby exerting a protective effect. These findings suggest that DAPA could serve as a novel therapeutic approach for patients with cardiac infarction.

2.
Macromol Biosci ; : e2400047, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589022

RESUMEN

Polyaspartic acid derivatives are a well-known kind of polypeptide with good biocompatibility and biodegradability, and thus have been widely used as biomedical materials, including drug-loaded nano-scale micelles or macroscopic hydrogels. In this work, for the first time, monodisperse polyaspartic acid derivative microspheres with diameter ranging from 120 to 350 µm for potential tumor embolization therapy are successfully prepared by single emulsion droplet microfluidic technique. The obtained microsphere shows fast cationic anticancer drug doxorubicin hydrochloride loading kinetics with high loading capacity, which is much better than those of the commercial ones. Additionally, drug release behaviors of the drug-loaded microspheres with different diameters in different media are also studied and discussed in detail. These results provide some new insights for the preparation and potential application of polyaspartic acid derivative-based monodisperse microspheres, especially for their potential application as embolic agent.

3.
Pestic Biochem Physiol ; 199: 105774, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38458681

RESUMEN

Aphis gossypii, a globally distributed and economically significant pest of several crops, is known to infest a wide range of host plants. Heat shock proteins (Hsps), acting as molecular chaperones, are essential for the insect's environmental stress responses. The present study investigated the molecular characteristics and expression patterns of AgHsp70, a heat shock protein gene, in Aphis gossypii. Our phylogenetic analysis revealed that AgHsp70 shared high similarity with homologs from other insects, suggesting a conserved function across species. The developmental expression profiles of AgHsp70 in A. gossypii showed that the highest transcript levels were observed in the fourth instar nymphs, while the lowest levels were detected in the third instar nymphs. Heat stress and exposure to four different xenobiotics (2-tridecanone, tannic acid, gossypol, and flupyradifurone (4-[(2,2-difluoroethyl)amino]-2(5H)-furanone)) significantly up-regulated AgHsp70 expression. Knockdown of AgHsp70 using RNAi obviously increased the susceptibility of cotton aphids to 2-tridecanone, gossypol and flupyradifurone. Dual-luciferase reporter assays revealed that gossypol and flupyradifurone significantly enhanced the promoter activity of AgHsp70 at a concentration of 10 mg/L. Furthermore, we identified the transcription factor heat shock factor (HSF) as a regulator of AgHsp70, as silencing AgHSF reduced AgHsp70 expression. Our results shed light on the role of AgHsp70 in xenobiotic adaptation and thermo-tolerance.


Asunto(s)
4-Butirolactona/análogos & derivados , Áfidos , Gosipol , Cetonas , Polifenoles , Piridinas , Animales , Áfidos/genética , Áfidos/metabolismo , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Gosipol/metabolismo , Filogenia , Xenobióticos/farmacología , Xenobióticos/metabolismo
4.
ACS Catal ; 14(1): 406-417, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38205022

RESUMEN

The oxygen species on Ag catalysts and reaction mechanisms for ethylene epoxidation and ethylene combustion continue to be debated in the literature despite decades of investigation. Fundamental details of ethylene oxidation by supported Ag/α-Al2O3 catalysts were revealed with the application of high-angle annular dark-field-scanning transmission electron microscopy-energy-dispersive X-ray spectroscopy (HAADF-STEM-EDS), in situ techniques (Raman, UV-vis, X-ray diffraction (XRD), HS-LEIS), chemical probes (C2H4-TPSR and C2H4 + O2-TPSR), and steady-state ethylene oxidation and SSITKA (16O2 → 18O2 switch) studies. The Ag nanoparticles are found to carry a considerable amount of oxygen after the reaction. Density functional theory (DFT) calculations indicate the oxidative reconstructed p(4 × 4)-O-Ag(111) surface is stable relative to metallic Ag(111) under the relevant reaction environment. Multiple configurations of reactive oxygen species are present, and their relevant concentrations depend on treatment conditions. Selective ethylene oxidation to EO proceeds with surface Ag4-O2* species (dioxygen species occupying an oxygen site on a p(4 × 4)-O-Ag(111) surface) only present after strong oxidation of Ag. These experimental findings are strongly supported by the associated DFT calculations. Ethylene epoxidation proceeds via a Langmuir-Hinshelwood mechanism, and ethylene combustion proceeds via combined Langmuir-Hinshelwood (predominant) and Mars-van Krevelen (minor) mechanisms.

5.
Polymers (Basel) ; 15(21)2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37959915

RESUMEN

The catalytic conversion of cellulose to lactic acid (LA) has garnered significant attention in recent years due to the potential of cellulose as a renewable and sustainable biomass feedstock. Here, a series of Au/W-ZnO catalysts were synthesized and employed to transform cellulose into LA. Through the optimization of reaction parameters and catalyst compositions, we achieved complete cellulose conversion with a selectivity of 54.6% toward LA over Au/W-ZnO at 245 °C for 4 h. This catalyst system also proved effective at converting cotton and kenaf fibers. Structural and chemical characterizations revealed that the synergistic effect of W, ZnO, and Au facilitated mesoporous architecture generation and the establishment of an adequate acidic environment. The catalytic process proceeded through the hydrolysis of cellulose to glucose, isomerization to fructose, and its subsequent conversion to LA, with glucose isomerization identified as the rate-limiting step. These findings provide valuable insights for developing high-performance catalytic systems to convert cellulose.

6.
Molecules ; 28(17)2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37687116

RESUMEN

Hericium erinaceus (HE), a widely utilized natural remedy and dietary source, has garnered significant attention for its therapeutic potential in various diseases. In this study, we employed supercritical fluid extraction (SFE) technology to isolate the bioactive compounds from HE's fruiting body. Comprehensive assessments of the antioxidant and antibacterial activities were conducted, along with in vitro investigations on the human colon cancer cell line (HCT-8). The SFE rate served as the evaluation metric, while the variables of extraction time, pressure, and temperature were systematically examined. By integrating the response surface center composite design, we successfully optimized the extraction process, yielding optimal parameters of 80 min, 30 MPa, and 35 °C, thus resulting in an extraction rate of 2.51%. These optimized conditions exhibited considerable antioxidant capacity, anticancer activity, and antibacterial potential. Furthermore, we employed graded alcohol extraction to refine the crude extracts, thereby confirming superior anticancer effects under a 70% alcohol precipitation. To elucidate the composition, Fourier-transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry (GC-MS) were employed to analyze the crude extracts and isolates of HE, facilitating a comparative analysis of six HE varieties. Our findings suggest that sterol derivatives hold promise as the active component against the colon cancer HCT-8 cell line. In conclusion, this study underscores the potential of HE SFE in the development of functional foods or alternative drugs for colon cancer treatment, thus opening new avenues for therapeutic interventions.


Asunto(s)
Neoplasias del Colon , Humanos , Antioxidantes/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Neoplasias del Colon/tratamiento farmacológico , Antibacterianos/farmacología
7.
Chem Commun (Camb) ; 59(43): 6544-6547, 2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37161882

RESUMEN

Herein, a series of Ru/ZTCs samples were prepared using LaY zeolite-templated carbon as a support. Characterizations showed that the unique structure of the ZTCs and the chemical state of Ru facilitated superior HER performance compared to other carbon-supported samples. This work offers a new strategy for designing excellent electrocatalysts.

8.
Front Public Health ; 10: 939095, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36311632

RESUMEN

Background: Chest computerized tomography (CT) plays an important role in detecting patients with suspected coronavirus disease 2019 (COVID-19), however, there are no systematic summaries on whether the chest CT findings of patients within mainland China are applicable to those found in patients outside. Methods: Relevant studies were retrieved comprehensively by searching PubMed, Embase, and Cochrane Library databases before 15 April 2022. Quality assessment of diagnostic accuracy studies (QUADAS) was used to evaluate the quality of the included studies, which were divided into two groups according to whether they were in mainland China or outside. Data on diagnostic performance, unilateral or bilateral lung involvement, and typical chest CT imaging appearances were extracted, and then, meta-analyses were performed with R software to compare the CT features of COVID-19 pneumonia between patients from within and outside mainland China. Results: Of the 8,258 studies screened, 19 studies with 3,400 patients in mainland China and 14 studies with 554 outside mainland China were included. Overall, the risk of quality assessment and publication bias was low. The diagnostic value of chest CT is similar between patients from within and outside mainland China (93, 91%). The pooled incidence of unilateral lung involvement (15, 7%), the crazy-paving sign (31, 21%), mixed ground-glass opacities (GGO) and consolidations (51, 35%), air bronchogram (44, 25%), vascular engorgement (59, 33%), bronchial wall thickening (19, 12%), and septal thickening (39, 26%) in patients from mainland China were significantly higher than those from outside; however, the incidence rates of bilateral lung involvement (75, 84%), GGO (78, 87%), consolidations (45, 58%), nodules (12, 17%), and pleural effusion (9, 15%) were significantly lower. Conclusion: Considering that the chest CT features of patients in mainland China may not reflect those of the patients abroad, radiologists and clinicians should be familiar with various CT presentations suggestive of COVID-19 in different regions.


Asunto(s)
COVID-19 , Humanos , COVID-19/diagnóstico por imagen , COVID-19/epidemiología , SARS-CoV-2 , Tomografía Computarizada por Rayos X/métodos , Bases de Datos Factuales , China/epidemiología
9.
Biochem Biophys Res Commun ; 627: 84-90, 2022 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-36030656

RESUMEN

Proton pump inhibitors (PPIs) are often prescribed in association with clopidogrel and aspirin to patients with myocardial infraction (MI), but their effects on heart is controversial. The purpose of this study was to investigate the effects and potential mechanism of omeprazole (OME) and esomeprazole (ESO) in myocardial ischemia reperfusion (I/R) injury. In the present study, mice were treated with OME, ESO or vehicle for 3 weeks and then subjected to myocardial I/R or sham surgery. At 1 day after surgery, echocardiography was performed to access cardiac injury. Hematoxylin and eosin (H&E) staining was performed to evaluate cardiomyocyte morphology. The IL1ß was evaluated by Immunohistochemistry (IHC). Elisa was used to detect cTnt content in serum. The expression of CD86, CD206, CHOP, ATF6, eIF2α and p eIF2α were determined by Western blot (WB). The result showed that ESO markedly improved the left ventricular ejection fraction (LVEF), shortening fraction (FS), suppressed inflammatory infiltration, endoplasmic reticulum stress (ERS) and decreased proinflammatory macrophages in I/R hearts, while OME had no significant effects on cardiac function, inflammation and ERS in the I/R heart. In conclusion, ESO but not OME pretreatment reduces the proportion of proinflammatory macrophages, inhibits endoplasmic reticulum stress, and alleviates I/R injury in mice, indicating that ESO maybe a more proper PPI than OME for application in I/R injury.


Asunto(s)
Daño por Reperfusión Miocárdica , Daño por Reperfusión , Animales , Apoptosis , Estrés del Retículo Endoplásmico , Esomeprazol/farmacología , Esomeprazol/uso terapéutico , Ratones , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Daño por Reperfusión Miocárdica/metabolismo , Miocitos Cardíacos/metabolismo , Volumen Sistólico , Función Ventricular Izquierda
10.
J Youth Adolesc ; 51(11): 2161-2172, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35861907

RESUMEN

A number of studies have focused on the same-sex peer effect on and the developmental difference in adolescent risk-taking in terms of the dual systems model. Little research, however, addresses the effects of different observers, the role of different levels of individual self-control, and their interactions. To fill this gap, the present study examined the main and interactive effects of observer presence and individual self-control on male adolescents' risk-taking behavior with an experimental design. A total of 261 male adolescents (Mage = 15.79 ± 0.79, range = 14-18) completed an adapted Stoplight Task, which measures risk-taking behavior, in the presence of an observer, either peer or adult, either male or female. The results indicated that a same-sex peer's presence and low self-control were both risk factors of male adolescents' risk-taking, but did only low self-control male adolescents take serious risks when in the presence of a same-sex peer whereas those with high self-control consistently had low levels of risk-taking under any condition. An opposite-sex observer, particularly an opposite-sex adult's presence, played a similar protective role for male adolescents with low self-control. The findings suggest that a high level of self-control closely related to the cognitive control system may significantly buffer the negative effect of an adverse social stimulus which activates the social-emotional system on male adolescents' risk-taking; the findings also reveal that an opposite-sex adult's presence may contribute to a decrease in male adolescents' risk-taking by improving their cognitive control system.


Asunto(s)
Conducta del Adolescente , Autocontrol , Adolescente , Conducta del Adolescente/psicología , Adulto , Femenino , Humanos , Masculino , Grupo Paritario , Asunción de Riesgos , Conducta Social
11.
Front Immunol ; 13: 1086103, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36591266

RESUMEN

ß-glucan is widely used in aquaculture due to its immunostimulatory effects, but the specific effect and potential regulatory mechanism on largemouth bass (Micropterus salmoides) are still unclear. Here, we evaluated the effects of ß-glucan on growth, resistance to Aeromonas schubertii, intestinal health, and transcriptome of largemouth bass to reveal the potential regulators, metabolic pathways, and altered differential microbiota. Four experimental diets were designed with ß-glucan supplementation levels of 0 (control), 100 (LA-100), 200 (MA-200), and 300 (HA-300) mg kg-1, and each diet was fed to largemouth bass (79.30 ± 0.50 g) in triplicate for 70 days, followed by a 3-day challenge experiment. Results showed that different ß-glucan supplementations had no significant effects on growth performance and whole-body composition. Fish fed a diet with 300 mg kg-1 ß-glucan significantly increased the activity of lysozyme than those fed diets with 0 and 100 mg kg-1 ß-glucan. In addition, the survival rate of largemouth bass in ß-glucan supplementation groups was significantly higher than the control group at 12- and 24-h challenge by Aeromonas schubertii. Transcriptome analysis showed that a total of 1,245 genes were differentially expressed [|log2(fold change)| ≥1, q-value ≤0.05], including 109 immune-related differentially expressed genes (DEGs). Further analysis revealed that significantly upregulated and downregulated DEGs associated with immunity were mapped into 12 and 24 pathways, respectively. Results of intestinal microflora indicated that fish fed a diet with 300 mg kg-1 ß-glucan had higher bacterial richness and diversity as evaluated by Sobs, Chao, Ace, and Simpson indices, but no significant differences were found in the comparison groups. Furthermore, 300 mg kg-1 ß-glucan significantly increased the relative abundance of Mycoplasma and decreased Proteobacteria (mainly Escherichia-Shigella and Escherichia coli) and Bacillus anthracis in largemouth bass intestinal microflora. The findings of this study provided new insights that will be valuable in future studies to elucidate the mechanism of immunity enhancement by ß-glucan.


Asunto(s)
Lubina , Transcriptoma , Animales , Dieta , Perfilación de la Expresión Génica/métodos
12.
Cancer Med ; 10(21): 7772-7780, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34528767

RESUMEN

BACKGROUND: To study the risk factors of Gleason score upgrading (GSU) after radical prostatectomy (RP) in a Chinese cohort. METHODS: The data of 637 patients who underwent prostate biopsy and RP in our hospital from January 2014 to January 2021 were retrospectively analyzed. The age, body mass index (BMI), prostate-specific antigen (PSA) level, testosterone (TT) level, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), eosinophil-to-lymphocyte ratio (ELR), aspartate aminotransferase/alanine transaminase (AST/ALT) ratio, clinical stage, the biopsy method, and pathological characteristics of specimens after biopsy and RP were collected for all patients. Univariate analysis and multivariate logistic regression analysis were used to analyze the risk factors of GSU after RP. The predictive efficacy was verified with the area under the curve (AUC) of the receiver operating characteristic (ROC) curve. We performed the analysis separately in the overall cohort and in the cohort with Gleason score (GS) = 6. RESULTS: In the overall cohort, 177 patients (27.79%) had GSU, and in the GS = 6 cohort, 68 patients (60.18%) had GSU. Multivariate logistic regression analysis showed that in the overall cohort, clinical stage ≥T2c (OR = 3.201, p < 0.001), the number of positive cores ≥3 (OR = 0.435, p = 0.04), and positive rate of biopsy (OR = 0.990, p = 0.016) can affect whether GS is upgraded, and the AUC of the combination of the three indicators for predicting the occurrence of GSU was 0.627. In the GS = 6 cohort, multivariate logistic regression analysis showed that clinical stage ≥T2c (OR = 4.690, p = 0.001) was a risk factor for GSU, and the AUC predicted to occur GSU is 0.675. CONCLUSION: Clinical stage ≥T2c, the number of positive cores <3, and lower positive rate of biopsy are the risk factors of GSU. This study may provide some references for clinicians to judge the accuracy of biopsy pathological grading and formulate treatment strategies, but the specific effect still needs clinical practice certification.


Asunto(s)
Clasificación del Tumor , Prostatectomía , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía , Anciano , Alanina Transaminasa/sangre , Pueblo Asiatico , Biopsia , Recuento de Células Sanguíneas , Índice de Masa Corporal , China , Humanos , Calicreínas/sangre , Masculino , Estadificación de Neoplasias , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/etnología , Estudios Retrospectivos , Factores de Riesgo , Testosterona/sangre , Transaminasas/sangre
13.
ACS Appl Mater Interfaces ; 13(21): 25365-25373, 2021 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-34003634

RESUMEN

In this work, we report the easy fabrication of highly transparent (optical transmittance above 93%), stretchable (1500-2500% elongation at break), and conductive (up to 2.25 S m-1 at 25 °C) supramolecular ionogels that simultaneously integrate with three-dimensional (3D) printable, healable, adhesive, and recyclable character. The supramolecular ionogel is designed using a linear amphiphilic poly(urethane-urea) (PUU) copolymer and ionic liquid (IL) as the elastic scaffold and electrolyte, respectively, via a simple cosolvent method. Intriguingly, the 3D-printed highly conductive (2.25 S m-1 at 25 °C) supramolecular ionogel structure shows record-high mechanical performance with a breaking tensile strain and stress of 945% and 1.51 MPa, respectively, and is able to lift 3400× or bear 10000× its weight without fracture. Furthermore, both the solution casting and 3D-printed ionogel films show high sensitivity and reliability for sensing a wide range of strains, including various human motions. The results present some new insights into the structural, mechanical, and functional design of novel multifunctional ionogels with distinguished mechanical performance and tractable processability, which will extend them to a wide range of flexible electronic applications, including artificial intelligence, wearable/conformable electronics, human/machine interactions, soft robotics, etc.

14.
Medicine (Baltimore) ; 99(28): e21180, 2020 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-32664160

RESUMEN

The association between sleep duration and prostate cancer (PCa) risk is still unclear. We performed a systematic review and meta-analysis to explore if sleep duration is associated with PCa in men.A comprehensive literature search was conducted in November 2019 based on the Pubmed, Embase, and Cochrane databases. After extracting the data, the random effects model was used to calculate the pooled Risk Ratio (RR) and it's 95% confidence interval (CI) to represent the correlation between sleep duration and PCa risk.Overall, we included 6 studies in our meta-analysis. Our pooled results showed that neither short sleep (RR = 0.99; 95%CI:0.91-1.07, P = .74) nor long sleep (RR = 0.88; 95%CI:0.75-1.04, P = .15) was associated with the risk of PCa.Sleep duration has no significant effect on PCa risk. Long sleep may have a potential protective effect on PCa incidence.


Asunto(s)
Neoplasias de la Próstata/etiología , Trastornos del Sueño-Vigilia/complicaciones , Sueño , Factores de Tiempo , Humanos , Masculino , Oportunidad Relativa
15.
J Youth Adolesc ; 49(8): 1674-1686, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32578000

RESUMEN

With China's fast-growing economy, family dinners are often overlooked. However, family dinner, as an important routine family activity, provides an opportunity for interaction between adolescents and their parents, which promotes adolescents' happiness. Guided by the positive youth development perspective, the character strength theory of happiness and the family investment model, the current study simultaneously investigated the mediating role of adolescents' internal assets and the moderating role of parental educational level in the influence of family dinner on adolescents' happiness in Chinese families. A three-wave longitudinal study spanning approximately three years was conducted among 817 Chinese seventh graders (52.4% male; Mage = 12.62 years). The frequency of family dinner at the first year was significantly positively correlated with adolescents' happiness in the first and third years. The cross-sectional and longitudinal results showed that adolescents' internal assets mediated the relationship between family dinner frequency and happiness. Specifically, family dinner with higher-educated parents was a stronger predictor of internal assets than family dinner with lower-educated parents after one year. These findings from the Chinese cultural context complement the research in this field and inform practical endeavors to promote adolescents' happiness worldwide based on the strengths of different cultures.


Asunto(s)
Felicidad , Padres , Adolescente , China , Estudios Transversales , Femenino , Humanos , Estudios Longitudinales , Masculino
16.
ACS Macro Lett ; 9(11): 1655-1661, 2020 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-35617066

RESUMEN

The strength and toughness are two trade-off properties of a material, yet Nature can achieve strong and tough materials by introducing sacrificial bonds into a system. Here, we present a four-component multiblock copolymer (mBCP) approach toward strong and tough elastic fibers, by introducing terpyridine moieties into poly(ether ester) mBCP elastomers. After coordination with Fe(II), supramolecular cross-links are formed within the physically cross-linked thermoplastic elastomers. The toughening elastic fibers with a double-cross-linked network structure show high tensile strength (ca. 300 MPa) and toughness (ca. 100 MJ m-3). In addition, they display excellent resilience with enhanced self-healing properties. Our strategy provides a promising way for the development of strong and tough elastomers by introducing metal-ligand sacrificial bonds into mBCPs elastomers.

17.
J Mater Sci Mater Med ; 30(12): 135, 2019 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-31802280

RESUMEN

The major challenge to treat the clinical adverse effects of long-segment urethra is in achieving viable tissue substitution. The substituted construct's properties-such as its resilience, contraction, and ability to minimize scar-stenosis formation should be considered. In the present work, a unique polyurethane-urea (PUU) fibrous membrane is fabricated by electrospinning. Then PUU was coated by collagen and formed the elasticity hydrogel after immersed in collagen solution. Meanwhile, the cPUU hydrogel exhibited a fibrous microstructure. This cPUU hydrogel had outstanding stretching property with 404 ± 40% elongation at break compared with traditional hydrogels, which satisfied the requirement of urethra. The cPUU hydrogel also supported the adhesion and growth of bladder smooth-muscle cells (BSMCs) in natural state cell morphology. Urethral defects in New Zealand male rabbits were repaired with cPUU seeded with BSMCs in vivo. After three months, more smooth-surface area of reconstructed urethral tissues was observed in the cPUU hydrogel-BMSCs groups compared with that of the control group. The luminal patency and the incidence of complications-including calculus formation, urinary fistula, and urethral-stricture occurrence were significantly lower in the cPUU group compared with that of the control group. Hence, cPUU fibrous hydrogels are promising scaffolds for application in urological tissue engineering.


Asunto(s)
Colágeno/química , Hidrogeles/química , Miocitos del Músculo Liso/fisiología , Poliuretanos/química , Urea/química , Enfermedades Uretrales/terapia , Animales , Materiales Biocompatibles , Masculino , Ensayo de Materiales , Conejos , Ingeniería de Tejidos , Andamios del Tejido , Vejiga Urinaria/citología
18.
Ultrason Sonochem ; 59: 104703, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31421613

RESUMEN

SSZ-13 zeolite has been widely used in catalysis and adsorption because of good hydrothermal stability and pore structure. However, long crystallization time is the main challenge limiting its industry application. As increased emissions and ineffective treatment, coal gangue not only occupies land, but also pollutes the waterbody and farmland. Using coal gangue as raw material to synthetize zeolite has been considered as an environmentally friendly and effective alternative to solve the issues of accumulation and pollution, which also improves the added value of coal gangue. The ultrasonic assistance has been proven to be one of the potential pretreatment methods to promote the dissolution of crystalline silicon aluminum and reduce the crystallization time of molecular sieve. In this work, SSZ-13 was synthesized by coal gangue via ultrasonic pretreatment combined with hydrothermal growth method. The ultrasonic frequency and power were 20 kHz and 120 W, respectively. The synthesized samples were characterized by XRD, SEM, EDS, BET. The results showed that the crystallization time was shorten to 18 h, which was about 12 h lower than the same conditions of conventional chemicals synthesis. Furthermore, the specific surface area of the synthesized sample was more than 620 m2/g, which also indicated over 95% NOx conversion across a broad range from 180 to 400 °C and over 94% NOx conversion at 200-400 °C after hydrothermal treatment 6 h. This study provides a reference for the environmentally friendly utilization of coal gangue and the low-cost rapid synthesis and application of SSZ-13.

19.
Adv Healthc Mater ; 8(13): e1900435, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31081247

RESUMEN

Nature has created many perfect helical microstructures, including DNA, collagen fibrils, and helical blood vessels, to achieve unique physiological functions. While previous studies have developed a number of microfabrication strategies, the preparation of complex helical structures and cell-laden helical structures for biomimetic applications remains challenging. In this study, a one-step microfluidics-based methodology is presented for preparing complex helical hydrogel microfibers and cell-laden helical hydrogel microfibers. Several types of complex helical structures, including multilayer helical microfibers and superhelical hollow microfibers with helical channels, are prepared by simply tuning the flow rates or modifying the geometry of microfluidic device. With the decent perfusability, the hollow microfibers may simulate the structural characteristics of helical blood vessels and create swirling blood flow in a blood-vessel-on-chip setup. Such hydrogel-based helical microstructures may potentially be used in areas such as blood vessel tissue engineering, organ-on-chips, drug screening, and biological actuators.


Asunto(s)
Hidrogeles/química , Microfluídica/métodos , Alginatos/química , Órganos Artificiales , Materiales Biomiméticos/química , Vasos Sanguíneos/química , Vasos Sanguíneos/ultraestructura , Colágeno/química , Células Endoteliales de la Vena Umbilical Humana , Humanos , Dispositivos Laboratorio en un Chip , Ingeniería de Tejidos
20.
Macromol Rapid Commun ; 40(12): e1900111, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30969013

RESUMEN

The helix and superhelix play critical roles in the achievement of tissue functions. These fascinating structures have attracted increasing interest due to their potential biomimicking applications. However, continuous and controlled fabrication of these structures, especially the superhelical structures, from various polymers for different practical applications still remains a big challenge. Here, a novel and versatile microfluidic spinning strategy is presented for generation of both helical and superhelical microfibers from either hydrophilic, hydrophobic, or amphiphilic polymers. The diameter (d ), wavelength (λ), and amplitude (A) of these microfibers could be highly controlled. The helical microfibers show outstanding elongations and potential applications in magnetic responsive elastic microactuators. It is envisioned that these results will greatly enrich the possibility of generating new multiple-ordered structures from various polymers for applications in different areas.


Asunto(s)
Técnicas Analíticas Microfluídicas , Polímeros/química , Interacciones Hidrofóbicas e Hidrofílicas , Sustancias Macromoleculares/química , Tamaño de la Partícula , Propiedades de Superficie
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