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1.
Biofabrication ; 16(4)2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39255833

RESUMEN

The transplantation of islet beta cells offers an alternative to heterotopic islet transplantation for treating type 1 diabetes mellitus (T1DM). However, the use of systemic immunosuppressive drugs in islet transplantation poses significant risks to the body. To address this issue, we constructed an encapsulated hybrid scaffold loaded with islet beta cells. This article focuses on the preparation of the encapsulated structure using 3D printing, which incorporates porcine pancreas decellularized extracellular matrix (dECM) to the core scaffold. The improved decellularization method successfully preserved a substantial proportion of protein (such as Collagen I and Laminins) architecture and glycosaminoglycans in the dECM hydrogel, while effectively removing most of the DNA. The inclusion of dECM enhanced the physical and chemical properties of the scaffold, resulting in a porosity of 83.62% ± 1.09% and a tensile stress of 1.85 ± 0.16 MPa. In teams of biological activity, dECM demonstrated enhanced proliferation, differentiation, and expression of transcription factors such as Ki67, PDX1, and NKX6.1, leading to improved insulin secretion function in MIN-6 pancreatic beta cells. In the glucose-stimulated insulin secretion experiment on day 21, the maximum insulin secretion from the encapsulated structure reached 1.96 ± 0.08 mIU ml-1, representing a 44% increase compared to the control group. Furthermore, conventional capsule scaffolds leaverage the compatibility of natural biomaterials with macrophages to mitigate immune rejection. Here, incorporating curcumin into the capsule scaffold significantly reduced the secretion of pro-inflammatory cytokine (IL-1ß, IL-6, TNF-α, IFN-γ) secretion by RAW264.7 macrophages and T cells in T1DM mice. This approach protected pancreatic islet cells against immune cell infiltration mediated by inflammatory factors and prevented insulitis. Overall, the encapsulated scaffold developed in this study shows promise as a natural platform for clinical treatment of T1DM.


Asunto(s)
Curcumina , Matriz Extracelular Descelularizada , Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Andamios del Tejido , Animales , Diabetes Mellitus Tipo 1/terapia , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/citología , Andamios del Tejido/química , Curcumina/farmacología , Curcumina/química , Ratones , Matriz Extracelular Descelularizada/química , Matriz Extracelular Descelularizada/farmacología , Porcinos , Trasplante de Islotes Pancreáticos , Cápsulas/química , Insulina/metabolismo , Diabetes Mellitus Experimental/terapia , Línea Celular , Matriz Extracelular/metabolismo , Matriz Extracelular/química
2.
Genome Biol Evol ; 16(7)2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38946321

RESUMEN

Oecanthus is a genus of cricket known for its distinctive chirping and distributed across major zoogeographical regions worldwide. This study focuses on Oecanthus rufescens, and conducts a comprehensive examination of its genome through genome sequencing technologies and bioinformatic analysis. A high-quality chromosome-level genome of O. rufescens was successfully obtained, revealing significant features of its genome structure. The genome size is 877.9 Mb, comprising ten pseudo-chromosomes and 70 other sequences, with a GC content of 41.38% and an N50 value of 157,110,771 bp, indicating a high level of continuity. BUSCO assessment results demonstrate that the genome's integrity and quality are high (of which 96.8% are single-copy and 1.6% are duplicated). Comprehensive genome annotation was also performed, identifying approximately 310 Mb of repetitive sequences, accounting for 35.3% of the total genome sequence, and discovering 15,481 tRNA genes, 4,082 rRNA genes, and 1,212 other noncoding genes. Furthermore, 15,031 protein-coding genes were identified, with BUSCO assessment results showing that 98.4% (of which 96.3% are single-copy and 1.6% are duplicated) of the genes were annotated.


Asunto(s)
Genoma de los Insectos , Anotación de Secuencia Molecular , Animales , Cromosomas de Insectos/genética , Gryllidae/genética , Ortópteros/genética , Ortópteros/clasificación
3.
Materials (Basel) ; 17(14)2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39063851

RESUMEN

Laser-based direct energy deposition (DED-LB/M) has been a promising option for the surface repair of structural aluminum alloys due to the advantages it offers, including a small heat-affected zone, high forming accuracy, and adjustable deposition materials. However, the unequal powder particle size during powder-based DED-LB/M can cause unstable flow and an uneven material flow rate per unit of time, resulting in defects such as pores, uneven deposition layers, and cracks. This paper presents a multiscale, multiphysics numerical model to investigate the underlying mechanism during the powder-based DED-LB/M surface repair process. First, the worn surfaces of aluminum alloy components with different flaw shapes and sizes were characterized and modeled. The fluid flow of the molten pool during material deposition on the worn surfaces was then investigated using a model that coupled the mesoscale discrete element method (DEM) and the finite volume method (FVM). The effect of flaw size and powder supply quantity on the evolution of the molten pool temperature, morphology, and dynamics was evaluated. The rapid heat transfer and variation in thermal stress during the multilayer DED-LB/M process were further illustrated using a macroscale thermomechanical model. The maximum stress was observed and compared with the yield stress of the adopted material, and no relative sliding was observed between deposited layers and substrate components.

4.
J Environ Manage ; 364: 121443, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38878575

RESUMEN

Nanofiltration (NF) has been proven to be with great potential for the separation of morpholines with molecular weight less than 200 Da in refining reverse osmosis concentrate (ROC), but its application is significantly restricted by the membrane fouling, which can reduce the rejection and service time. To enable the long-term operation stability of nanofiltration, this work focuses on the fouling behavior of each substance in the hydrosaline organic solution on nanofiltration membrane, aiming to give insight into the fouling mechanism. To this end, in this work, the effects of salts (i.e NaCl and Na2SO4), organic substances (including N-(2-hydroxypropyl)morpholine(NMH) and 4-morpholineacetate(MHA)) and representative divalent ions (Ca2+ and Mg2+) on the performance and physicochemical properties of DK membrane were systematically investigated. The results show that both salts and organics can induce DK membrane swelling, leading to an increase of the mean effective pore size. After the filtration of Na2SO4-NaCl-H2O, the mean pore size increased by 0.002 nm, resulting in the decrease of the removal ratio of NMH and MHA for 3.82% and 13.10%, respectively. With static adsorption of NMH and MHA, the mean pore size of DK membrane increased by 0.005 and 0.003 nm. The swelling slowed the entrance of more organic molecules into membrane pores. Among them, MHA led to the terrible irreversible pore blocking. As the concentration of Ca2+ increased, gypsum scaling was formed on the membrane surface. During this process, NMH and MHA played different roles, i.e. NMH accelerated the CaSO4 crystallization while MHA inhibited. As a conclusion, the fouling behavior of substances in the high saline organic wastewater on DK membrane were systematically revealed with the fouling mechanisms proposed, which could provide an insightful guidance for membrane fouling control and cleaning in the treatment of high salinity and organic wastewater.


Asunto(s)
Filtración , Membranas Artificiales , Ósmosis , Purificación del Agua , Purificación del Agua/métodos , Morfolinas/química , Adsorción
6.
Acta Psychol (Amst) ; 246: 104248, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38598923

RESUMEN

Well-being is one of the central topics in psychology, and research on this topic has shifted from emotional experiences to flourishing life in recent years. Seligman's PERMA model is a prominent theory in this shift. However, this model is proposed in Western culture and has yet to be empirically validated in the Chinese context. The present research aims to examine the applicability of the five-dimension PERMA-Profiler in Chinese culture, which has been developed based on the PERMA model. A sample of 1468 Chinese adults participated in the research. After translation and validation, a series of psychometric analyses were conducted to examine the internal consistency reliability, construct validity, convergent and discriminant validity, and factorial invariance across genders. The PERMA-Profiler Chinese showed high Cronbach's alpha coefficients (α = 0.79-0.88), good divergent (r = -0.19 to -0.38) and convergent validity (r = 0.53-0.85), as well as satisfactory structural validity. Results of the structural validity demonstrated a better fit to the first-order model with five correlated factors after modification (χ2/df = 4.65, RMSEA = 0.058, SRMR = 0.030, CFI = 0.943, TLI = 0.924) than the second-order model with a higher-order factor of well-being. However, the engagement dimension of the PERMA-Profiler Chinese could be improved further. In conclusion, the PERMA model is applicable to the Chinese culture, and the PERMA-Profiler provides a valid measure of well-being for Chinese adults.


Asunto(s)
Salud Poblacional , Psicometría , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Pueblo Asiatico , China , Satisfacción Personal , Psicometría/normas , Psicometría/instrumentación , Psicometría/métodos , Reproducibilidad de los Resultados , Encuestas y Cuestionarios/normas
7.
Int J Biol Macromol ; 267(Pt 1): 131204, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38556242

RESUMEN

Cellulose, renowned for its excellent biocompatibility, finds extensive applications in both industrial and laboratory settings. However, few studies have specifically addressed the mechanistic evolution of hydrogen bond networks in cellulose during the dissolution and regeneration processes. In this research, the regeneration mechanism of cellulose in water and ethanol is investigated through molecular dynamics simulations. The results indicate that the ability of water molecules to disrupt hydrogen bonds between cellulose and ionic liquids is stronger than that of ethanol, which is more conducive to promoting the regeneration of cellulose. Besides, the Fourier transform infrared spectroscopy coupled with two-dimensional correlation infrared spectroscopy techniques are employed to unveil the evolution sequence of hydrogen bonds during dissolution and regeneration: ν(OH) (absorbed water) â†’ ν(O3-H3···O5) (intrachain) â†’ ν(O6-H6···O3') (interchain) â†’ ν(O2-H2···O6) (intrachain) â†’ ν(OH) (free). This study not only enhances our understanding of the intricate hydrogen bond dynamics in cellulose dissolution and regeneration but also provides a foundation for the expanded application of cellulose in diverse fields.


Asunto(s)
Celulosa , Enlace de Hidrógeno , Líquidos Iónicos , Simulación de Dinámica Molecular , Solventes , Agua , Celulosa/química , Agua/química , Solventes/química , Líquidos Iónicos/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Etanol/química , Espectrofotometría Infrarroja
8.
ACS Appl Mater Interfaces ; 16(14): 18063-18074, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38537174

RESUMEN

Bacterial infections have become a serious threat to public health. The utilization of antibacterial textiles offers an effective way to combat bacterial infections at the source, instead of relying solely on antibiotic consumption. Herein, efficient and durable antibacterial fibers based on quercetin and cellulose were prepared by a triaxial microfluidic spinning technology using ionic liquids (ILs) as the solvents. It was indicated that the structure and properties of the antibacterial fibers were affected by the type of IL and the flow rates during the triaxial microfluidic spinning process. Quercetin regenerated from [Emim]Ac underwent structural transformation and obtained an increased water solubility, while quercetin regenerated from [Emim]DEP remained unchanged, which was proven by FI-IR, XRD, and UV analyses. Furthermore, antibacterial fibers regenerated from [Emim]Ac exhibited the highest antibacterial activity of 96.9% against S. aureus, achieved by reducing the inner-to-outer flow rate ratio to 0 and concentrating quercetin at the center of fibers. On the other hand, when [Emim]DEP was used as the solvent, balancing the inner-to-outer flow rate ratio to concentrate quercetin in the middle layer of the fiber was optimal for achieving the best antibacterial activity of 93.3% because it promised both the higher encapsulation efficiency and release rate. Computational fluid dynamics (CFD) mathematically predicted the solvent exchange process during triaxial spinning, explaining the influence of IL types and flow rates on quercetin distribution and encapsulation efficiency. It was indicated that optimizing the distribution of antibacterial agents within the fibers can fully unleash its antibacterial potential while preserving the mechanical properties of the fiber. Therefore, the proposed simple triaxial spinning strategy provides valuable insights into the design of biomedical materials.


Asunto(s)
Infecciones Bacterianas , Líquidos Iónicos , Humanos , Solventes/química , Líquidos Iónicos/farmacología , Líquidos Iónicos/química , Microfluídica , Staphylococcus aureus , Quercetina/farmacología , Antibacterianos/farmacología , Antibacterianos/química
9.
Biochem Pharmacol ; 222: 116073, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38395263

RESUMEN

Stem cells from the apical papilla(SCAPs) exhibit remarkable tissue repair capabilities, demonstrate anti-inflammatory and pro-angiogenic effects, positioning them as promising assets in the realm of regenerative medicine. Recently, the focus has shifted towards exosomes derived from stem cells, perceived as safer alternatives while retaining comparable physiological functions. This study delves into the therapeutic implications of exosomes derived from SCAPs in the methionine-choline-deficient (MCD) diet-induced mice non-alcoholic steatohepatitis (NASH) model. We extracted exosomes from SCAPs. During the last two weeks of the MCD diet, mice were intravenously administered SCAPs-derived exosomes at two distinct concentrations (50 µg/mouse and 100 µg/mouse) biweekly. Thorough examinations of physiological and biochemical indicators were performed to meticulously evaluate the impact of exosomes derived from SCAPs on the advancement of NASH in mice induced by MCD diet. This findings revealed significant reductions in body weight loss and liver damage induced by the MCD diet following exosomes treatment. Moreover, hepatic fat accumulation was notably alleviated. Mechanistically, the treatment with exosomes led to an upregulation of phosphorylated adenosine monophosphate-activated protein kinase (p-AMPK) levels in the liver, enhancing hepatic fatty acid oxidation and transporter gene expression while inhibiting genes associated with fatty acid synthesis. Additionally, exosomes treatment increased the transcription levels of key liver mitochondrial marker proteins and the essential mitochondrial biogenesis factor. Furthermore, the levels of serum inflammatory factors and hepatic tissue inflammatory factor mRNA expression were significantly reduced, likely due to the anti-inflammatory phenotype induced by exosomes in macrophages. The above conclusion suggests that SCAPs-exosomes can improve NASH.


Asunto(s)
Deficiencia de Colina , Exosomas , Enfermedad del Hígado Graso no Alcohólico , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Metionina/metabolismo , Colina/metabolismo , Metabolismo de los Lípidos , Exosomas/metabolismo , Deficiencia de Colina/complicaciones , Deficiencia de Colina/tratamiento farmacológico , Deficiencia de Colina/metabolismo , Hígado/metabolismo , Inflamación/metabolismo , Racemetionina/metabolismo , Racemetionina/farmacología , Antiinflamatorios/farmacología , Dieta , Ácidos Grasos/metabolismo , Ratones Endogámicos C57BL
10.
Adv Mater ; 36(23): e2312209, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38262622

RESUMEN

Harvesting electricity from widespread water evaporation provides an alternative route to cleaner power generation technology. However, current evaporation power generation (EPG) mainly depends on the dissociation process of certain functional groups (e.g., SO3H) in water, which suffers from low power density and short-term output. Herein, the Janus membrane is prepared by combining nanofluid and water-grabbing material for EPG, where the nanoconfined ionic liquids (NCILs) serve as ion sources instead of the functional groups. Benefiting from the selective and fast transport of anions in NCILs, such EPG demonstrates excellent power performance with a voltage of 0.63 V, a short-circuit current of 140 µA, and a maximum power density of 16.55 µW cm-2 while operating for at least 180 h consistently. Molecular dynamics (MD) simulation and surface potential analysis reveal the molecular mechanism, that is, the diffusion of Cl- anions during evaporation is much faster than that of cations, generating the voltage and current across the membrane. Furthermore, the device performs well in varying environmental conditions, including different water temperatures and sources of evaporating water, showcasing its adaptability and integrability. Overall, the nanofluid-guided Janus membrane can efficiently transform low-grade thermal energy in evaporation into electricity, showing a competitive advantage over other sustainable applied approaches.

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