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1.
Bioact Mater ; 37: 348-377, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38694766

RESUMEN

Setting time as the fourth dimension, 4D printing allows us to construct dynamic structures that can change their shape, property, or functionality over time under stimuli, leading to a wave of innovations in various fields. Recently, 4D printing of smart biomaterials, biological components, and living cells into dynamic living 3D constructs with 4D effects has led to an exciting field of 4D bioprinting. 4D bioprinting has gained increasing attention and is being applied to create programmed and dynamic cell-laden constructs such as bone, cartilage, and vasculature. This review presents an overview on 4D bioprinting for engineering dynamic tissues and organs, followed by a discussion on the approaches, bioprinting technologies, smart biomaterials and smart design, bioink requirements, and applications. While much progress has been achieved, 4D bioprinting as a complex process is facing challenges that need to be addressed by transdisciplinary strategies to unleash the full potential of this advanced biofabrication technology. Finally, we present future perspectives on the rapidly evolving field of 4D bioprinting, in view of its potential, increasingly important roles in the development of advanced dynamic tissues for basic research, pharmaceutics, and regenerative medicine.

2.
Biomed Mater ; 19(3)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38636508

RESUMEN

Spinal cord injury (SCI) is a devastating neurological disorder, leading to loss of motor or somatosensory function, which is the most challenging worldwide medical problem. Re-establishment of intact neural circuits is the basis of spinal cord regeneration. Considering the crucial role of electrical signals in the nervous system, electroactive bioscaffolds have been widely developed for SCI repair. They can produce conductive pathways and a pro-regenerative microenvironment at the lesion site similar to that of the natural spinal cord, leading to neuronal regeneration and axonal growth, and functionally reactivating the damaged neural circuits. In this review, we first demonstrate the pathophysiological characteristics induced by SCI. Then, the crucial role of electrical signals in SCI repair is introduced. Based on a comprehensive analysis of these characteristics, recent advances in the electroactive bioscaffolds for SCI repair are summarized, focusing on both the conductive bioscaffolds and piezoelectric bioscaffolds, used independently or in combination with external electronic stimulation. Finally, thoughts on challenges and opportunities that may shape the future of bioscaffolds in SCI repair are concluded.


Asunto(s)
Traumatismos de la Médula Espinal , Andamios del Tejido , Traumatismos de la Médula Espinal/terapia , Traumatismos de la Médula Espinal/fisiopatología , Humanos , Animales , Regeneración Nerviosa , Axones/fisiología , Materiales Biocompatibles/química , Ingeniería de Tejidos/métodos , Médula Espinal , Conductividad Eléctrica , Regeneración de la Medula Espinal , Estimulación Eléctrica/métodos
3.
Adv Sci (Weinh) ; : e2309166, 2024 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-38493495

RESUMEN

The construction of bioartificial livers, such as liver organoids, offers significant promise for disease modeling, drug development, and regenerative medicine. However, existing methods for generating liver organoids have limitations, including lengthy and complex processes (taking 6-8 weeks or longer), safety concerns associated with pluripotency, limited functionality of pluripotent stem cell-derived hepatocytes, and small, highly variable sizes (typically ≈50-500 µm in diameter). Prolonged culture also leads to the formation of necrotic cores, further restricting size and function. In this study, a straightforward and time-efficient approach is developed for creating rapid self-assembly mini-livers (RSALs) within 12 h. Additionally, primary hepatocytes are significantly expanded in vitro for use as seeding cells. RSALs exhibit consistent larger sizes (5.5 mm in diameter), improved cell viability (99%), and enhanced liver functionality. Notably, RSALs are functionally vascularized within 2 weeks post-transplantation into the mesentery of mice. These authentic hepatocyte-based RSALs effectively protect mice from 90%-hepatectomy-induced liver failure, demonstrating the potential of bioartificial liver-based therapy.

4.
Int Urol Nephrol ; 56(1): 205-215, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37204678

RESUMEN

PURPOSE: This current study scrutinized the association among left ventricular mass index (LVMI), ratio of high-density lipoprotein (HDL) and C-reactive protein (CRP), and renal function. Furthermore, we examined the predictive effects of left ventricular mass index and HDL/CRP on progression of non-dialysis chronic kidney disease. METHODS: We enrolled adult patients with chronic kidney disease (CKD) who were not receiving dialysis and obtained follow-up data on them. We extracted and compared data between different groups. To investigate the relationship between left ventricular mass index (LVMI), high-density lipoprotein (HDL)/C-reactive protein (CRP) levels, and CKD, we employed linear regression analysis, Kaplan-Meier analysis, and Cox proportional hazards regression analysis. RESULTS: Our study enrolled a total of 2351 patients. Compared with those in the non-progression group, subjects in the CKD progression group had lower ln(HDL/CRP) levels (- 1.56 ± 1.78 vs. - 1.14 ± 1.77, P < 0.001) but higher left ventricular mass index (LVMI) values (115.45 ± 29.8 vs. 102.8 ± 26.31 g/m2, P < 0.001). Moreover, after adjusting for demographic factors, ln(HDL/CRP) was found to be positively associated with estimated glomerular filtration rate (eGFR) (B = 1.18, P < 0.001), while LVMI was negatively associated with eGFR (B = - 0.15, P < 0.001). In the end, we found that both LVH (HR = 1.53, 95% CI 1.15 to 2.05, P = 0.004) and lower ln(HDL/CRP) (HR = 1.46, 95% CI 1.08 to 1.96, P = 0.013) independently predicted CKD progression. Notably, the combined predictive power of these variables was stronger than either variable alone (HR = 1.98, 95% CI 1.5 to 2.62, P < 0.001). CONCLUSION: Our study findings indicate that in pre-dialysis patients, both HDL/CRP and LVMI are associated with basic renal function and are independently correlated with CKD progression. These variables may serve as predictors for CKD progression, and their combined predictive power is stronger than that of either variable alone.


Asunto(s)
Proteína C-Reactiva , Insuficiencia Renal Crónica , Adulto , Humanos , Lipoproteínas HDL , Diálisis , Factores de Riesgo , Insuficiencia Renal Crónica/complicaciones , Tasa de Filtración Glomerular , Antibacterianos , Penicilinas , Hipertrofia Ventricular Izquierda/complicaciones
5.
Int Urol Nephrol ; 56(3): 1173-1184, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37728808

RESUMEN

BACKGROUND: As chronic kidney disease (CKD) progresses, metabolites undergo diverse transformations. Nevertheless, the impact of these metabolic changes on the etiology, progression, and prognosis of CKD remains uncertain. Our objective is to conduct a metabolomics analysis to scrutinize metabolites and identify significant metabolic pathways implicated in CKD progression, thereby pinpointing potential therapeutic targets for CKD management. METHODS: We recruited 145 patients with CKD and determined their mGFR by measuring the plasma iohexol clearance, whereupon we partitioned them into four groups based on their mGFR values. Non-targeted metabolomics analysis was conducted using UPLC-MS/MS assays. Differential metabolites were identified via one-way ANOVA, PCA, PLS-DA, and OPLS-DA analyses employing the MetaboAnalyst 5.0 platform. Ultimately, we performed differential metabolite pathway enrichment analysis, using both the MetaboAnalyst 5.0 platform and the MBRole2.0 database. RESULTS: According to the findings of the MBRole2.0 and MetaboAnalyst 5.0 enrichment analysis, six amino acid metabolism pathways were discovered to have significant roles in the progression of CKD, with the glycine, serine, and threonine metabolism pathway being the most prominent. The latter enriched 14 differential metabolites, of which six decreased while two increased concomitantly with renal function deterioration. CONCLUSIONS: The metabolic analysis unveiled that glycine, serine, and threonine metabolism plays a pivotal role in the progression of CKD. Specifically, glycine was found to increase while serine decreased with the deterioration of CKD.


Asunto(s)
Aminoácidos , Insuficiencia Renal Crónica , Humanos , Cromatografía Liquida , Espectrometría de Masas en Tándem , Metabolómica , Glicina , Serina , Treonina , Biomarcadores
6.
Food Chem ; 439: 138168, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38103491

RESUMEN

Papaya is a climacteric fruit that undergoes rapid ripening and quality deterioration during postharvest storage, resulting in significant economic losses. This study employed biochemical techniques and targeted metabolomics to investigate the impact of exogenous AsA + CTS application on the energy metabolism regulation of papaya fruit during postharvest storage. We found that AsA + CTS treatment significantly increased the levels of key metabolic compounds and enzymes, such as adenosine triphosphate (ATP), adenosine diphosphate (ADP), and the energy charge, as well as the succinic acid content and the activities of succinic dehydrogenase (SDH), cytochrome c oxidase (CCO), H+-ATPase, and Ca2+-ATPase. Moreover, AsA + CTS coating augmented the nicotinamide adenine dinucleotide kinase (NADK) activity and increased the NADH and NADPH concentrations. Regarding sugar metabolism, it increased the activities of 6-phosphogluconate dehydrogenase and glucose-6-phosphate dehydrogenase and raised d-glucose-6-phosphate levels. These findings suggest that AsA + CTS coating application can mitigate the metabolic deterioration and sustain a primary metabolism homeostasis in papaya fruit by enhancing the tricarboxylic acid (TCA) cycle and pentose phosphate pathway (PPP), thereby preserving their quality attributes during postharvest storage.


Asunto(s)
Carica , Quitosano , Frutas/química , Ácido Ascórbico/análisis , Quitosano/análisis , Homeostasis
7.
J Inflamm Res ; 16: 5273-5285, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38026247

RESUMEN

Purpose: Scant research has been conducted on the interplay between the systemic inflammation response index (SIRI) and chronic kidney disease (CKD). The present study endeavors to meticulously scrutinize the association between SIRI and renal function. Additionally, we aim to assess its efficacy in predicting the progression of CKD in non-dialysis patients. Patients and Methods: Adult patients with CKD who were not undergoing dialysis were enrolled, and follow-up data were obtained. Data from distinct groups were extracted and meticulously compared. A comprehensive analytical approach was adopted, including logistic regression analysis, Kaplan-Meier analysis, Cox proportional hazards regression analysis, and subgroup analysis. Results: Our study included 1420 patients, with a mean age of 61 ± 17 years, and 63% were male. 244 (17.2%) patients experienced the progression of CKD. As the level of ln(SIRI) increased, patients tended to be older, with a higher proportion of males, and increased prevalence rates of hypertension, stroke, heart failure, and progression of CKD. Additionally, the levels of baseline creatinine and C-reactive protein were elevated, while the levels of estimated glomerular filtration rate and hemoglobin decreased. Upon adjusting for demographic and biochemical variables, logistic regression analysis indicated that ln(SIRI) was independently associated with advanced CKD in pre-dialysis patients (OR=1.59, 95% CI: 1.29-1.95, P<0.001). Moreover, Cox proportional-hazard analysis revealed that ln(SIRI) independently predicted CKD progression (HR: 1.3, 95% CI: 1.07-1.59, P=0.009). Conducting a subgroup analysis, we observed significant interactions between ln(SIRI) levels and gender (p<0.001), age (p=0.046), and hypertension (p=0.028) in relation to the progression of CKD. Conclusion: Our study's findings demonstrate a significant association between SIRI and fundamental renal function, and independently establish a correlation between SIRI and the progression of CKD in pre-dialysis patients. These observations suggest that SIRI holds promise as a potential predictor for CKD progression.

8.
J Colloid Interface Sci ; 650(Pt B): 1881-1892, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37517188

RESUMEN

Schizophrenic copolymers are one type of the popular smart polymers that show invertible colloidal structures in response to temperature stimulus. However, the lack of principles to predict the phase transition temperature of a schizophrenic copolymer from its corresponding parent thermo-responsive polymers limits their development. Additionally, studies on their applications remain scarce. Herein, a series of schizophrenic copolymers were synthesized by polymerization of a RAFT-made polymer precursor poly(acrylamide-co-N-acryloxysuccinimide-co-acrylic acid) (P(AAm-co-NAS-co-AAc)) with the mixture of N-isopropylmethacrylamide (NIPAm) and acrylamide (AAm) in varying molar ratios. In aqueous solution, the block P(AAm-co-NAS-co-AAc) and the block poly(NIPAm-co-AAm) exhibited upper and lower critical solution temperature (UCST and LCST) behavior, respectively. The schizophrenic copolymers featured either UCST-LCST, LCST-UCST, or only LCST thermo-responsive transition. A preliminary correlation of phase transition between the schizophrenic copolymers and their parent polymers was summarized. Furthermore, the co-assembly of the schizophrenic copolymers and proteins were conducted and the kinetics of protein loading and protein activity were investigated, which showed that the schizophrenic copolymers were efficient platforms for protein co-assembly with ultra-high protein loading while preserving the protein bioactivities. Additionally, all the materials were non-toxic towards NIH 3T3 and MCF-7 cells. This work offers the prospects of the schizophrenic polymers in soft colloidal and assembly systems, particularly in guiding the design of new materials and their use in biomedical applications.


Asunto(s)
Polímeros , Esquizofrenia , Humanos , Polímeros/química , Proteínas , Agua , Temperatura , Acrilamidas/química
9.
Biomacromolecules ; 24(6): 2928-2941, 2023 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-37212876

RESUMEN

Gelatin methacryloyl (GelMA) hydrogels have been extensively used for drug delivery and tissue engineering applications due to their good biocompatibility, biodegradability, and controllable photocurable efficiency. Phosphate buffer solution (PBS) is the most widely used reaction system for GelMA synthesis. However, carbonate-bicarbonate buffer solution (CBS) has been tried recently for synthesizing GelMA due to its high reaction efficiency. However, there is a lack of systematic investigation into possible differences in the structure and properties of GelMA synthesized in PBS and CBS, respectively. Therefore, in the current study, GelMA molecules with two degrees of methacryloylation (∼20 and ∼80%) were synthesized under PBS and CBS reaction systems, respectively, in comparable conditions. The results showed that because of the functionalization of methacrylate groups in gelatin chains, which could interfere with the intrachain and interchain interactions, such as hydrogen bonding, the GelMA molecules synthesized in PBS had distinct physical structures and exhibited different properties in comparison with those produced in CBS. GelMA hydrogels synthesized in PBS exhibited higher gel-sol transition temperatures and better photocurable efficiencies, mechanical strength, and biological properties. In contrast, GelMA hydrogels produced in CBS showed advantages in swelling performance and microstructures, such as pore sizes and porosities. In addition, GelMA synthesized in PBS and possessing a high degree of methacryloylation (the "GelMA-PH" polymer) showed great potential for three-dimensional (3D) bioprinting. This focused study has gained helpful new insights into GelMA and can provide guidance on the application of GelMA in 3D printing and tissue engineering.


Asunto(s)
Gelatina , Metacrilatos , Gelatina/química , Metacrilatos/química , Ingeniería de Tejidos/métodos , Impresión Tridimensional , Hidrogeles/química , Andamios del Tejido/química
10.
Biol Trace Elem Res ; 201(12): 5501-5511, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36973606

RESUMEN

The association between selenium (Se) and lipid profile has been controversial in different populations, and the aim of the study was to investigate the relationship between Se and lipid profile in patients with chronic kidney disease (CKD). A total of 861 US adult patients with CKD (male: female = 404:457) from the National Health and Nutrition Examination Survey database were enrolled in this cross-sectional study. We used smoothing spline plots and multivariate binary logistic regression analyses to elucidate the relationships between blood Se and lipid profile. Multivariate adjusted smoothing spline plots showed that higher levels of blood Se were associated with higher levels of serum remnant cholesterol (RC), total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) levels. Threshold and saturation effects were also observed between serum RC, TC, TG, LDL-C, and blood Se. In multivariate binary logistic regression analyses, the fully adjusted model showed that as blood Se increases by every 1 µg/L, the OR of high RC, high TG and high LDL-C in patients was 1.012 (95% CI: 1.001, 1.023 P = 0.046), 1.011 (95% CI: 1.001, 1.021 P = 0.043) and 1.009 (95% CI: 1.003, 1.016 P = 0.012), respectively. Furthermore, stratified analyses showed that the associations between blood Se and high RC/high TG were significantly stronger in patients aged < 65 years. Higher levels of blood Se were associated with increased serum lipid profile levels and increased risk of high RC, high TC, high LDL-C, and low HDL-C dyslipidemia in adult patients with CKD in the US. However, the real associations between blood Se and lipid profiles in this population should be verified in future prospective and randomized trials.


Asunto(s)
Insuficiencia Renal Crónica , Selenio , Humanos , Adulto , Masculino , Femenino , Encuestas Nutricionales , LDL-Colesterol , Lípidos , Estudios Transversales , HDL-Colesterol , Triglicéridos
11.
ACS Appl Mater Interfaces ; 15(6): 7867-7877, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36740782

RESUMEN

Poly(N-acryloyl glycinamide) (PNAGA) can form high-strength hydrogen bonds (H-bonds) through the dual amide motifs in the side chain, allowing the polymer to exhibit gelation behavior and an upper critical solution temperature (UCST) property. These features make PNAGA a candidate platform for biomedical devices. However, most applications focused on PNAGA hydrogels, while few focused on PNAGA nanoparticles. Improving the UCST tunability and bio-interfacial adhesion of the PNAGA nanoparticles may expand their applications in biomedical fields. To address the issues, we established a reactive H-bond-type P(NAGA-co-NAS) copolymer via reversible addition-fragmentation chain transfer polymerization of NAGA and N-acryloxysuccinimide (NAS) monomers. The UCST behaviors and the bio-interfacial adhesion toward the proteins and cells along with the potential application of the copolymer nanoparticles were investigated in detail. Taking advantage of the enhanced H-bonding and reactivity, the copolymer exhibited a tunable UCST in a broad temperature range, showing thermo-reversible transition between nanoparticles (PNPs) and soluble chains; the PNPs efficiently bonded proteins into nano-biohybrids while keeping the secondary structure of the protein, and more importantly, they also exhibited good adhesion ability to the cell membrane and significantly inhibited cell-specific propagation. These features suggest broad prospects for the P(NAGA-co-NAS) nanoparticles in the fields of biosensors, protein delivery, cell surface decoration, and cell-specific function regulation.


Asunto(s)
Hidrogeles , Nanopartículas , Hidrogeles/química , Temperatura , Polímeros/química , Nanopartículas/química
12.
Front Psychol ; 13: 996497, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36275314

RESUMEN

Drawing on the integration of social exchange theory and situational power theory, this paper explores the effect of servant leadership on young university teachers' workplace well-being and explores the mediating effect of occupational commitment and the moderating effect of risk perception on the indirect effects of servant leadership on workplace well-being. A questionnaire was distributed using the Questionnaire Star online questionnaire platform and a two-wave time-lagged design was used to collect 215 survey samples of young teachers from Chinese higher education institutions. SPSS 23.0 was used to test the hypothesized relationship between the variables. Results revealed that servant leadership was positively related to young university teachers' workplace well-being. Occupational commitment plays a partial mediating role in linking servant leadership and young university teachers' workplace well-being. Risk perception plays a moderating role in the indirect relationship between servant leadership, occupational commitment, and workplace well-being. When risk perception has a low level, the mediating effect of occupational commitment is stronger.

13.
Biofabrication ; 14(4)2022 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-35896092

RESUMEN

Compared to other conventional scaffold fabrication techniques, three-dimensional (3D) printing is advantageous in producing bone tissue engineering scaffolds with customized shape, tailored pore size/porosity, required mechanical properties and even desirable biomolecule delivery capability. However, for scaffolds with a large volume, it is highly difficult to get seeded cells to migrate to the central region of the scaffolds, resulting in an inhomogeneous cell distribution and therefore lowering the bone forming ability. To overcome this major obstacle, in this study, cell-laden bone tissue engineering scaffolds consisting of osteogenic peptide (OP) loadedß-tricalcium phosphate (TCP)/poly(lactic-co-glycolic acid) (PLGA) (OP/TCP/PLGA, designated as OTP) nanocomposite struts and rat bone marrow derived mesenchymal stem cell (rBMSC)-laden gelatin/GelMA hydrogel rods were produced through 'dual-nozzle' low temperature hybrid 3D printing. The cell-laden scaffolds exhibited a bi-phasic structure and had a mechanical modulus of about 19.6 MPa, which was similar to that of human cancellous bone. OP can be released from the hybrid scaffolds in a sustained manner and achieved a cumulative release level of about 78% after 24 d. rBMSCs encapsulated in the hydrogel rods exhibited a cell viability of about 87.4% right after low temperature hybrid 3D printing and could be released from the hydrogel rods to achieve cell anchorage on the surface of adjacent OTP struts. The OP released from OTP struts enhanced rBMSCs proliferation. Compared to rBMSC-laden hybrid scaffolds without OP incorporation, the rBMSC-laden hybrid scaffolds incorporated with OP significantly up-regulated osteogenic differentiation of rBMSCs by showing a higher level of alkaline phosphatase expression and calcium deposition. This 'proof-of-concept' study has provided a facile method to form cell-laden bone tissue engineering scaffolds with not only required mechanical strength, biomimetic structure and sustained biomolecule release profile but also excellent cell delivery capability with uniform cell distribution, which can improve the bone forming ability in the body.


Asunto(s)
Células Madre Mesenquimatosas , Osteogénesis , Animales , Diferenciación Celular , Humanos , Hidrogeles , Péptidos/química , Porosidad , Impresión Tridimensional , Ratas , Temperatura , Ingeniería de Tejidos/métodos , Andamios del Tejido/química
14.
Front Behav Neurosci ; 15: 760547, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34887734

RESUMEN

Lumbar disc herniation (LDH) with radicular pain is a common and complicated musculoskeletal disorder. Our previous study showed that LDH-induced methylglyoxal (MG) accumulation contributed to radicular pain. The underlying mechanisms through which MG accumulates are poorly understood. In the present study, we found that both MG and tumor necrosis factor-alpha (TNF-ɑ) levels in the herniated disc of patients with radicular pain were significantly increased, and the activity of Glyoxalase 1 (GLO1), the rate-limiting enzyme that metabolizes MG, was decreased. In rats, the LDH model was mimicked by implantation of autologous nucleus pulposus (NP) to the left lumbar five spinal nerve root. The mechanical allodynia was observed in LDH rats. Besides, MG and TNF-ɑ levels were increased, and GLO1 activity was significantly decreased in the implanted NP. In cultured rat NP cells, stimulation with the inflammatory mediator TNF-ɑ reduced GLO1 activity and expression. These results suggested that TNF-ɑ-induced GLO1 activity decrease contributed to MG accumulation in the herniated disc of patients with radicular pain.

15.
Biomacromolecules ; 22(4): 1346-1356, 2021 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-33657790

RESUMEN

Developing a versatile bioadhesive which is biocompatible, adhesive, hemostatic, and therapeutic is of great significance to promote wound sealing and healing. Herein, an adhesive (GTT-3 hydrogel) is fabricated by catalysis of tannic acid modified gelatin (Gel-TA) with transglutaminase (TG). The hydrogen bonding, imine linking, and acyl-transfer reaction between GTT-3 hydrogel and tissue enable efficient hydrogel integration and adhesion to tissue instantly, so as to seal the wound and stop bleeding. Moreover, the intrinsic wound healing ability of gelatin and the antibacterial properties of TA provide favorable conditions for wound healing after adhesion. In vitro mechanical property testing and cell experimental results determine the elasticity, adhesion, and biocompatibility of the GTT-3 hydrogel. The wound operation in mouse models and pathological sectioning results indicate that GTT-3 adhesive obviously accelerates hemostasis, wound bonding, and healing. With the special property of instant adhesion and excellent hemostatic and therapeutic repair effects, GTT-3 hydrogel may provide a new option for surgical operation.


Asunto(s)
Hidrogeles , Cicatrización de Heridas , Animales , Antibacterianos/uso terapéutico , Catálisis , Gelatina , Hemostasis , Ratones
16.
Bioact Mater ; 6(1): 137-145, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32817920

RESUMEN

Three-dimensional (3D) printing has been increasingly employed to produce advanced bone tissue engineering scaffolds with biomimetic structures and matched mechanical strengths, in order to induce improved bone regeneration in defects with a critical size. Given that the successful bone regeneration requires both excellent osteogenesis and vascularization, endowing scaffolds with both strong bone forming ability and favorable angiogenic potential would be highly desirable to induce improved bone regeneration with required vascularization. In this investigation, customized bone tissue engineering scaffolds with balanced osteoconductivity/osteoinductivity were produced via cryogenic 3D printing of ß-tricalcium phosphate and osteogenic peptide (OP) containing water/poly(lactic-co-glycolic acid)/dichloromethane emulsion inks. The fabricated scaffolds had a hierarchically porous structure and were mechanically comparable to human cancellous bone. Angiogenic peptide (AP) containing collagen I hydrogel was then coated on scaffold surface to further provide scaffolds with angiogenic capability. A sequential release with a quick AP release and a slow but sustained OP release was obtained for the scaffolds. Both rat endothelial cells (ECs) and rat bone marrow derived mesenchymal stem cells (MSCs) showed high viability on scaffolds. Improved in vitro migration and angiogenesis of ECs were obtained for scaffolds delivered with AP while enhanced osteogenic differentiation was observed in scaffolds containing OP. The in vivo results showed that, toward scaffolds containing both AP and OP, the quick release of AP induced obvious angiogenesis in vivo, while the sustained OP release significantly improved the new bone formation. This study provides a facile method to produce dual-delivery scaffolds to achieve multiple functions.

17.
Opt Express ; 28(16): 24056-24068, 2020 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-32752391

RESUMEN

The scintillation index of plane wave propagation in anisotropic underwater turbulence under moderate-to-strong turbulent conditions is analyzed in this paper. A closed-form expression for the average channel capacity of underwater wireless optical communication (UWOC) systems is also proposed based on the Málaga fading model. The newly derived capacity model is effective in evaluating the influence of the link distance, the wavelength, the receiving aperture diameter, the anisotropic factor, the dissipation rate of mean squared temperature, and the eddy diffusivity ratio on the performance of these systems. Simulation results show that applying a large receiving aperture diameter and wavelength can improve the UWOC quality significantly. The contributions of anisotropy, temperature, and salinity also need to be considered in practical UWOC applications. The results reported in this paper will be helpful to researchers designing UWOC systems.

18.
ACS Appl Mater Interfaces ; 12(20): 23311-23322, 2020 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-32349481

RESUMEN

Dendritic macromolecules are potential candidates for nanomedical application. Herein, glycogen, the natural hyperbranched polysaccharide with favorable biocompatibility, is explored as an effective drug vehicle for treating liver cancer. In this system, glycogen is oxidized and conjugated with cancer drugs through a disulfide link, followed by in situ loading of polypyrrole nanoparticles and then coated with functional phospholipids to form the desired system, Gly-ss-DOX@ppy@Lipid-RGD. The phospholipid layer has good cell affinity and can assist the system to penetrate into cells smoothly. Additionally, combined with the "fusion targeting" of glycogen and the active targeting effect of RGD toward liver cancer cells, Gly-ss-DOX@ppy@Lipid-RGD presents efficient specificity and enrichment of hepatocellular carcinoma. Owing to the glutathione-triggered cleavage of disulfide linkers, Gly-ss-DOX@ppy@Lipid-RGD can controllably release drugs to induce cell nucleus damage. Meanwhile, the polypyrrole nanoparticles can absorb near-infrared light and radiate heat energy within tumors. Besides enhancing drug release, the heat can also provide photothermal treatment for tumors. As proved by in vitro and in vivo experiments, Gly-ss-DOX@ppy@Lipid-RGD is a remarkable candidate for synergistic chemophotothermal therapy with high anticancer therapeutic activity and reduced systematic toxicity, efficiently suppressing tumor growth. All results demonstrate that glycogen nanoparticles are expected to be a new building block for accurate hepatocellular carcinoma treatment.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Doxorrubicina/uso terapéutico , Glucógeno/química , Neoplasias Hepáticas/tratamiento farmacológico , Nanopartículas/química , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Terapia Combinada , Doxorrubicina/química , Doxorrubicina/farmacología , Liberación de Fármacos , Glucógeno/toxicidad , Hemólisis/efectos de los fármacos , Humanos , Hipertermia Inducida/métodos , Rayos Infrarrojos , Ratones Endogámicos BALB C , Nanopartículas/efectos de la radiación , Nanopartículas/toxicidad , Fosfolípidos/química , Fosfolípidos/toxicidad , Fotoquimioterapia , Polímeros/química , Polímeros/efectos de la radiación , Polímeros/toxicidad , Pirroles/química , Pirroles/efectos de la radiación , Pirroles/toxicidad
19.
Appl Opt ; 59(8): 2551-2558, 2020 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-32225796

RESUMEN

Underwater optical communication has been a promising technology but is severely affected by underwater turbulence due to the resulting fluctuations in the index of refraction. In this paper, a revised spatial power spectrum model is obtained that considers the refraction index to be a function of the eddy diffusivity ratio, assuming the underwater turbulence is anisotropic. The scintillation indices for both plane and spherical waves that propagate in underwater turbulence are derived based on this model. Thereafter, the performance of an optical communication system, i.e., the outage probability and bit error rate, with the associated aperture averaging effect is considered. The simulation results demonstrate that temperature-induced and salinity-induced turbulence have distinct influences on the scintillation index and consequently result in different system performances. In addition, the variation in the eddy diffusivity ratio in some intervals induces more complicated results for underwater optical communication. Moreover, the effect of the receiver aperture diameter on the aperture averaging factor is presented in anisotropic underwater turbulence. Such an effect is more obvious in the plane wave case than in the spherical wave case. These results can find potential application in the engineering design of optical communication systems in an underwater environment.

20.
ACS Appl Bio Mater ; 3(1): 421-431, 2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-35019458

RESUMEN

Injected tissue-affinity drug-laden nanocomposite hydrogels are promising materials for tumor therapy owing to both maintenance and release of drug in situ. In this study, a hyaluronic acid (HA) hydrogel covalently embedded with doxorubicin loaded and triphenylphosphine (TPP) modified core-shell gold mesoporous silica nanoparticles is fabricated as a local drug-delivery system for sustained stomach cancer treatment. HA has excellent biocompatibility as the main component of the extracellular matrix and specific affinity toward the CD44-overexpressed cancer cell. TPP is a classic targeted feature of mitochondria. After in situ injection, the hydrogel patch can adhesively land at the tumor site, and it exerts further control through dissociation because of the degradation of hyaluronidase around the solid tumor, leading to the release of core-shell gold mesoporous silica nanoparticles conjugated with TPP and HA fragment. These particles can selectively attack cancer cells followed by entering into mitochondria. Additionally, the core gold nanoparticle mediates the transformation of near-infrared radiation into thermal energy, enhancing the release of chemotherapy drugs and heat-induced cellular injury. This in situ, chemophotothermal combination hydrogel is verified to have an excellent therapeutic effect on gastric tumor through in vitro and in vivo experiments, providing the potential to serve as a multistage-target drug-delivery platform for chemophotothermal synergistic cancer therapy.

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