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1.
Plant Biotechnol J ; 22(7): 1981-1988, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38425137

RESUMEN

Succulents, valued for their drought tolerance and ornamental appeal, are important in the floriculture market. However, only a handful of succulent species can be genetically transformed, making it difficult to improve these plants through genetic engineering. In this study, we adapted the recently developed cut-dip-budding (CDB) gene delivery system to transform three previously recalcitrant succulent varieties - the dicotyledonous Kalanchoe blossfeldiana and Crassula arborescens and the monocotyledonous Sansevieria trifasciata. Capitalizing on the robust ability of cut leaves to regenerate shoots, these plants were successfully transformed by directly infecting cut leaf segments with the Agrobacterium rhizogenes strain K599. The transformation efficiencies were approximately 74%, 5% and 3.9%-7.8%, respectively, for K. blossfeldiana and C. arborescens and S. trifasciata. Using this modified CDB method to deliver the CRISPR/Cas9 construct, gene editing efficiency in K. blossfeldiana at the PDS locus was approximately 70%. Our findings suggest that succulents with shoot regeneration ability from cut leaves can be genetically transformed using the CDB method, thus opening up an avenue for genetic engineering of these plants.


Asunto(s)
Agrobacterium , Edición Génica , Plantas Modificadas Genéticamente , Transformación Genética , Edición Génica/métodos , Agrobacterium/genética , Plantas Modificadas Genéticamente/genética , Sistemas CRISPR-Cas/genética , Hojas de la Planta/genética , Kalanchoe/genética , Técnicas de Transferencia de Gen
2.
Phytochem Anal ; 35(4): 860-872, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38361458

RESUMEN

INTRODUCTION: Liuweizhiji Gegen-Sangshen (LGS) oral liquid is a Chinese patent medicine that is widely used for the prevention and treatment of alcoholic liver disease in clinical practice. However, the chemical complexity of LGS has not yet been investigated. OBJECTIVE: The aim of this study was to rapidly identify chemical constituents of LGS and establish a quality control method based on fingerprint and quantitative analysis. METHODOLOGY: A comprehensive strategy was used by combining qualitative analysis by ultra-performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and fingerprint analysis by high-performance liquid chromatography with diode array detection (HPLC-DAD). RESULTS: A total of 162 chemical components in LGS, including 91 flavonoids, 31 organic acids, and 20 phenolic compounds, were identified or preliminarily characterized in both positive and negative ion modes based on the UPLC-Q-TOF-MS results. Of these, 37 were confirmed with the reference standards. In fingerprint analysis, 23 peaks were chosen as common peaks and used to evaluate the similarity of different batches of LGS. Subsequently, a rapid quantification method was optimized and validated for the simultaneous determination of multiple chemical markers in LGS. The validated quantitative method was successfully used to analyze different batches of LGS samples. CONCLUSION: The proposed comprehensive strategy combining HPLC-DAD fingerprinting and multi-component quantification demonstrated satisfactory results with high efficiency, accuracy, and reliability. This can be used as a reference for the overall quality consistency evaluation of Chinese patent medicines.


Asunto(s)
Medicamentos Herbarios Chinos , Control de Calidad , Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Flavonoides/análisis , Espectrometría de Masas/métodos , Reproducibilidad de los Resultados , Administración Oral , Fenoles/análisis
3.
Small ; 19(11): e2207468, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36564364

RESUMEN

In situ fabrication of macroscale ordered monolayers of nanoparticles (NPs) on targeted substrates is highly desirable for precision electronic and optical devices, while it remains a great challenge. In this study, a solution is provided to address this challenge by developing a colloidal ink formulation and employing the direct-ink-writing (DIW) technique, where on-demand delivery of ink at a targeted location and directional evaporation with controllable rate are leveraged to precisely guide the deposition of polystyrene-grafted gold NPs (Au@PS NPs) into a macroscale monolayer with an ordered Au NP array embedded in a PS thin film. A 2D steady-state diffusion-controlled evaporation model, which explains the parameter dependence of the experimental results and gives semiquantitative agreement with the experimental evaporation kinetics is proposed. The ordered monolayer is used as both nanocrystal floating gates and the tunneling layer for nonvolatile memory devices. It shows significantly enhanced performance compared with a disordered NP film prepared by spin coating. This approach allows for fine control of NP self-assembly to print macroscaleordered monolayers directly onto substrates, which has great promise for application in broad fields, including microelectronic and photoelectronic devices, sensors, and functional coatings.

4.
Mol Ecol ; 32(14): 3859-3871, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37194687

RESUMEN

Domesticated honeybees and wild bees are some of the most important beneficial insects for human and environmental health, but infectious diseases pose a serious risk to these pollinators, particularly following the emergence of the ectoparasitic mite Varroa destructor as a viral vector. The acquisition of this novel viral vector from the Asian honeybee Apis ceranae has fundamentally changed viral epidemiology in its new host, the western honeybee A. mellifera. While the recently discovered Lake Sinai Viruses (LSV) have been associated with weak honeybee colonies, they have not been associated with vector-borne transmission. By combining a large-scale multi-year survey of LSV in Chinese A. mellifera and A. cerana honeybee colonies with globally available LSV-sequence data, we investigate the global epidemiology of this virus. We find that globally distributed LSV is a highly diverse multi-strain virus, which is predominantly associated with the western honeybee A. mellifera. In contrast to the vector-borne deformed wing virus, LSV is not an emerging disease. Instead, demographic reconstruction and strong global and local population structure indicates that it is a highly variable multi-strain virus in a stable association with its main host, the western honeybee. Prevalence patterns in China suggest a potential role for migratory beekeeping in the spread of this pathogen, demonstrating the potential for disease transmission with the man-made transport of beneficial insects.


Asunto(s)
Abejas , Virus ARN , Varroidae , Animales , Humanos , Abejas/parasitología , Abejas/virología , China/epidemiología , Virus ARN/genética , Varroidae/virología , Virus
5.
Cell Mol Biol (Noisy-le-grand) ; 69(9): 234-238, 2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37807306

RESUMEN

To uncover the potential effect of Perindopril on cardiac fibrosis caused by pressure overload and the underlying mechanism. Cardiac fibrosis model in mice was established by TAC method. Mice were assigned into sham group, TAC group, 2 mg/kg Perindopril group (Per (2 mg/kg)) and 8 mg/kg Perindopril group (Per (8 mg/kg)). Cardiac structure changes were assessed by measuring HW/BW, HW/TBL, LW/BW and LW/TBL in each group. Echocardiography was performed to assess mouse cardiac function by recording EF, LVIDd, IVSd and LVPWd. Relative levels of fibrosis markers were determined. AngII content was examined by ELISA. Besides, mRNA levels of key genes in the AngII/AT1R pathway were finally detected. TAC induced cardiac insufficiency, left ventricular dilatation, cardiac hypertrophy and myocardial collagen deposition in mice. In addition, fibrosis markers were upregulated in mice of TAC group. Perindopril markedly reversed TAC-induced pathological changes in cardiac structure and function of mice. Meanwhile, Perindopril dose-dependently reversed the upregulated genes in the AngII/AT1R pathway. Perindopril improves cardiac fibrosis induced by pressure overload through activating the AngII/AT1R pathway.


Asunto(s)
Cardiomiopatías , Perindopril , Ratones , Animales , Perindopril/farmacología , Perindopril/uso terapéutico , Corazón , Cardiomegalia/patología , Cardiomiopatías/metabolismo , Miocardio/metabolismo , Fibrosis , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad
6.
Molecules ; 28(3)2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36771080

RESUMEN

Efficient and mild synthetic routes for bioactive natural product derivatives are of current interest for drug discovery. Herein, on the basis of the pharmacophore hybrid strategy, we report a two-step protocol to obtain a series of structurally novel oleanolic acid (OA)-dithiocarbamate conjugates in mild conditions with high yields. Moreover, biological evaluations indicated that representative compound 3e exhibited the most potent and broad-spectrum antiproliferative effects against Panc1, A549, Hep3B, Huh-7, HT-29, and Hela cells with low cytotoxicity on normal cells. In terms of the IC50 values, these OA-dithiocarbamate conjugates were up to 30-fold more potent than the natural product OA. These compounds may be promising hit compounds for the development of novel anti-cancer drugs.


Asunto(s)
Antineoplásicos , Ácido Oleanólico , Humanos , Estructura Molecular , Relación Estructura-Actividad , Células HeLa , Antineoplásicos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Proliferación Celular
7.
J Am Chem Soc ; 144(4): 1690-1699, 2022 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-35007085

RESUMEN

Interest in developing antibacterial polymers as synthetic mimics of host defense peptides (HPDs) has accelerated in recent years to combat antibiotic-resistant bacterial infections. Positively charged moieties are critical in defining the antibacterial activity and eukaryotic toxicity of HDP mimics. Most examples have utilized primary amines or guanidines as the source of positively charged moieties, inspired by the lysine and arginine residues in HDPs. Here, we explore the impact of amine group variation (primary, secondary, or tertiary amine) on the antibacterial performance of HDP-mimicking ß-peptide polymers. Our studies show that a secondary ammonium is superior to either a primary ammonium or a tertiary ammonium as the cationic moiety in antibacterial ß-peptide polymers. The optimal polymer, a homopolymer bearing secondary amino groups, displays potent antibacterial activity and the highest selectivity (low hemolysis and cytotoxicity). The optimal polymer displays potent activity against antibiotic-resistant bacteria and high therapeutic efficacy in treating MRSA-induced wound infections and keratitis as well as low acute dermal toxicity and low corneal epithelial cytotoxicity. This work suggests that secondary amines may be broadly useful in the design of antibacterial polymers.


Asunto(s)
Aminas/química , Antibacterianos/uso terapéutico , Staphylococcus aureus Resistente a Meticilina/patogenicidad , Péptidos/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Infección de Heridas/tratamiento farmacológico , Animales , Antibacterianos/química , Antibacterianos/farmacología , Péptidos Catiónicos Antimicrobianos/química , Escherichia coli/efectos de los fármacos , Hemólisis/efectos de los fármacos , Queratitis/tratamiento farmacológico , Queratitis/microbiología , Queratitis/patología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Ratones , Pruebas de Sensibilidad Microbiana , Péptidos/química , Péptidos/farmacología , Polímeros/química , Infecciones Estafilocócicas/microbiología , Infección de Heridas/microbiología
8.
J Gen Virol ; 103(8)2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35947094

RESUMEN

Black queen cell virus (BQCV) is a severe threat to the honeybee (Apis mellifera) worldwide. Although several BQCV strains have been reported in China, the molecular basis for BQCV pathogenicity has not been well understood. Thus, a reverse genetic system of BQCV is required for studying viral replication and its pathogenic mechanism. Here, the complete genome sequence of BQCV was obtained from honeybees using reverse transcription PCR (RT-PCR), namely a BQCV China-GS1 strain (KY741959). Then, a phylogenetic tree was built to analyse the genetic relationships among BQCV strains from different regions. Our results showed that the BQCV China-GS1 contained two ORFs, consistent with the known reference strains, except for the BQCV China-JL1 strain (KP119603). Furthermore, the infectious clone of BQCV was constructed based on BQCV China-GS1 using a low copy vector pACYC177 and gene recombination. Due to the lack of culture cells for bee viruses, we infected the healthy bees with infectious clone of BQCV, and the rescued BQCV resulted in the recovery of recombinant virus, which induced higher mortality than those of the control group. Immune response after inoculated with BQCV further confirmed that the infectious clone of BQCV caused the cellular and humoral immune response of honeybee (A. mellifera). In conclusion, the full nucleotide sequence of BQCV China-GS1 strain was determined, and the infectious clone of BQCV was constructed in this study. These data will improve the understanding of pathogenesis and the host immune responses to viral infection.


Asunto(s)
Dicistroviridae , Virus ARN , Virus , Animales , Abejas , Dicistroviridae/genética , Sistemas de Lectura Abierta , Filogenia , Virus ARN/genética , Virus/genética
9.
Sensors (Basel) ; 22(8)2022 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-35458996

RESUMEN

At present, magnetic bearings are a better energy-saving choice than mechanical bearings in industrial applications. However, there are strongly coupled characteristics in magnetic bearing-rotor systems with redundant structures, and uncertain disturbances in the electrical system as well as external disturbances, and these unfavorable factors degrade the performance of the system. To improve the anti-interference performance of magnetic bearing systems, this paper proposes the inverse of the current distribution matrix W-1 meaning that the active disturbance rejection control simulation model can be carried out without neglecting the current of each coil. Firstly, based on the working mechanism of magnetic bearings with redundant structures and the nonlinear electromagnetic force model, the current and displacement stiffness models of magnetic bearings are established, and a dynamic model of the rotor is constructed. Then, according to the dynamic model of the rotor and the mapping relationship between the current of each coil and the electromagnetic force of the magnetic bearing, we established the equivalent control loop of the magnetic bearing-rotor system with redundant structures. Finally, on the basis of the active disturbance rejection control (ADRC) strategy, we designed a linear active disturbance rejection controller (LADRC) for magnetic bearings with redundant structures under the condition of no coil failure, and a corresponding simulation was carried out. The results demonstrate that compared to PID+current distribution control strategy, the LADRC+current distribution control strategy proposed in this paper is able to effectively improve the anti-interference performance of the rotors supported by magnetic bearings with redundant structures.

10.
J Environ Sci (China) ; 114: 10-20, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35459476

RESUMEN

Atmospheric particulate matter pollution has attracted much wider attention globally. In recent years, the development of atmospheric particle collection techniques has put forwards new demands on the real-time source apportionments techniques. Such demands are summarized, in this paper, as how to set up new restraints in apportionment and how to develop a non-linear regression model to process complicated circumstances, such as the existence of secondary source and similar source. In this study, we firstly analyze the possible and potential restraints in single particle source apportionment, then propose a novel three-step self-feedback long short-term memory (SF-LSTM) network for approximating the source contribution. The proposed deep learning neural network includes three modules, as generation, scoring and refining, and regeneration modules. Benefited from the scoring modules, SF-LSTM implants four loss functions representing four restraints to be followed in the apportionment, meanwhile, the regeneration module calculates the source contribution in a non-linear way. The results show that the model outperforms the conventional regression methods in the overall performance of the four evaluation indicators (residual sum of squares, stability, sparsity, negativity) for the restraints. Additionally, in short time-resolution analyzing, SF-LSTM provides better results under the restraint of stability.


Asunto(s)
Redes Neurales de la Computación , Material Particulado , Retroalimentación , Análisis de Regresión
11.
Sensors (Basel) ; 21(16)2021 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-34450844

RESUMEN

Fault tolerance is one of the effective methods to improve the reliability of magnetic bearings, and the redundant magnetic bearing provides a feasible measure for fault-tolerant control. The linearization and accuracy of the electromagnetic force (EMF) from the redundant structures is crucial for designing fault-tolerant controllers. In the magnetic bearing with a redundant structure, the current distribution matrix W is an important factor that affects the accuracy of EMF. In this paper, we improved the accuracy of the EMF model and took the eight-pole symmetrical radial magnetic bearing as the research object. The corresponding displacement compensation matrices have been calculated for the different coils that fail in the magnetic bearing while the rotor is at the non-equilibrium position. Then, we propose a fault-tolerant control strategy that includes displacement compensation. The rigid body dynamics model of the rotor, supported by magnetic bearings with redundant structures, is established. Moreover, to verify the effectiveness of the proposed control strategy, we combined the rigid body dynamics model of the rotor with a fault-tolerant control strategy, and the corresponding simulation has been carried out. In the case of disturbance force and some coils fail in magnetic bearing and compared with the fault-tolerant control that absents the displacement compensation factors. The simulations demonstrate the disturbance rejection of magnetically levitated rotor system can be enhanced. The robustness of the rotor has been improved with the fault-tolerant control strategy proposed in this paper.

12.
Int J Mol Sci ; 21(5)2020 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-32143291

RESUMEN

Honey bee viruses are associated with honey bee colony decline. Israeli acute paralysis virus (IAPV) is considered to have a strong impact on honey bee survival. Phylogenetic analysis of the viral genomes from several regions of the world showed that various IAPV lineages had substantial differences in virulence. Chronic bee paralysis virus (CBPV), another important honey bee virus, can induce two significantly different symptoms. However, the infection characteristics and pathogenesis of IAPV and CBPV have not been completely elucidated. Here, we constructed infectious clones of IAPV and CBPV using a universal vector to provide a basis for studying their replication and pathogenesis. Infectious IAPV and CBPV were rescued from molecular clones of IAPV and CBPV genomes, respectively, that induced typical paralysis symptoms. The replication levels and expression proteins of IAPV and CBPV in progeny virus production were confirmed by qPCR and Western blot. Our results will allow further dissection of the role of each gene in the context of viral infection while helping to study viral pathogenesis and develop antiviral drugs using reverse genetics systems.


Asunto(s)
Abejas/virología , Dicistroviridae/genética , Virus de Insectos/genética , Genética Inversa , Animales , Genoma Viral , Filogenia , Virosis/veterinaria
13.
Entropy (Basel) ; 21(3)2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33267000

RESUMEN

Carbon capture by adsorption is supposed to be an effective method to reduce CO2 emissions, among which Temperature Swing Adsorption (TSA) can utilize low-grade thermal energy even from renewable energy source. At present, TSA technology still has several challenges to be practical application, such as intensive energy-consumption and low energy-efficiency. Thermodynamics could be a powerful method to explore the energy conversion mechanism of TSA, among which entropy analysis could further provide a clear picture on the irreversible loss, even with a possible strategy of energy-efficient improvement. Based on the theory of non-equilibrium thermodynamics, the entropy analysis of TSA cycle is conducted, using the Computational Fluid Dynamics (CFD) method. The physical model and conservation equations are established and calculation methods for entropy generation are presented as well. The entropy generation of each process in cycle is analyzed, and the influence from the main parameters of desorption process is presented with optimization analysis. Finally, the performance of the cycle with regeneration is compared with that of the cycle without regeneration, and the method of reducing the entropy generation is obtained as well. This paper provides possible directions of performance improvement of TSA cycle with regards on energy utilization efficiency and the reduction of irreversible loss.

14.
J Gen Virol ; 98(11): 2864-2875, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29058655

RESUMEN

By providing pollination services, bees are among the most important insects, both in ecological and economical terms. Combined next-generation and classical sequencing approaches were applied to discover and study new insect viruses potentially harmful to bees. A bioinformatics virus discovery pipeline was used on individual Illumina transcriptomes of 13 wild bees from three species from the genus Halictus and 30 ants from six species of the genera Messor and Aphaenogaster. This allowed the discovery and description of three sequences of a new virus termed Halictus scabiosae Adlikon virus (HsAV). Phylogenetic analyses of ORF1, RNA-dependent RNA-polymerase (RdRp) and capsid genes showed that HsAV is closely related to (+)ssRNA viruses of the unassigned Sinaivirus genus but distant enough to belong to a different new genus we called Halictivirus. In addition, our study of ant transcriptomes revealed the first four sinaivirus sequences from ants (Messor barbarus, M. capitatus and M. concolor). Maximum likelihood phylogenetic analyses were performed on a 594 nt fragment of the ORF1/RdRp region from 84 sinaivirus sequences, including 31 new Lake Sinai viruses (LSVs) from honey bees collected in five countries across the globe and the four ant viral sequences. The phylogeny revealed four main clades potentially representing different viral species infecting honey bees. Moreover, the ant viruses belonged to the LSV4 clade, suggesting a possible cross-species transmission between bees and ants. Lastly, wide honey bee screening showed that all four LSV clades have worldwide distributions with no obvious geographical segregation.


Asunto(s)
Hormigas/virología , Abejas/virología , Virus de Insectos/clasificación , Virus de Insectos/aislamiento & purificación , Filogenia , Animales , Variación Genética , Virus de Insectos/genética , Análisis de Secuencia de ADN , Proteínas Virales/genética
15.
Arch Virol ; 162(8): 2451-2456, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28432563

RESUMEN

Chronic bee paralysis virus (CBPV) is an important viral pathogen that affects adult bees. Although several CBPV strains have been reported, little information has been obtained from China. In this study, two major segments of the CBPV Chinese isolate CBPV-BJ, RNA 1 and RNA 2, were determined to be 3657 and 2267 nucleotides (nt) in length, respectively. RNA 1 and RNA 2 contained three and four open reading frames (ORFs), respectively, which agreed with known reference strains (EU122229 and EU122230). The RNA 1 had 98% nucleotide sequence identity to a known Chinese strain (KU950353), and RNA 2 had 97% nucleotide sequence identity to another Chinese strain (KU950354). Although the lengths of the RNA 1 and RNA 2 sequences were 17 nt and 38 nt shorter than those of the CBPV reference strains EU122229 and EU122230, respectively, the complete CBPV-BJ RNA 1 and RNA 2 sequences shared 91% and 92% identity with them. Phylogenetic analysis based on the sequences of the RNA-dependent RNA polymerase (RdRp) and putative structural proteins (pSPs) showed that CBPV-BJ was most closely related to the other two Chinese isolate (KU950353 and KU950354) and clustered with most Asian strains. These data provide new information that will lead to a better understanding of the diversity of the CBPV genome.


Asunto(s)
Abejas/virología , Virus de Insectos/genética , Virus ARN/genética , ARN Viral/genética , Animales , China , Variación Genética , Genoma Viral , Virus de Insectos/aislamiento & purificación , Virus de Insectos/patogenicidad , Sistemas de Lectura Abierta , Virus ARN/aislamiento & purificación , Análisis de Secuencia de ARN
16.
J Invertebr Pathol ; 138: 112-5, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27369386

RESUMEN

Although many honey bee RNA viruses have been correlated with colony declines, little is known regarding the potential role of DNA viruses. Here, we examined seemingly healthy and crawling bee samples from China using PCR to identify whether Apis mellifera filamentous virus (AmFV) was present in A. cerana cerana. The highest AmFV infection percentage among Chinese provinces occurred in crawling bees from Gansu province (85.48%), and the lowest was in bees from Beijing (31.58%). A phylogenetic analysis showed that the Chinese isolate of AmFV exhibited a high genetic similarity with isolates from Belgium, Switzerland and USA. This is the first report of AmFV infections in Chinese A. cerana cerana populations.


Asunto(s)
Abejas/virología , Virosis/veterinaria , Animales , China , Virus ADN , Genes Virales/genética , Filogenia , Reacción en Cadena de la Polimerasa
17.
ACS Appl Mater Interfaces ; 16(19): 25124-25135, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38709893

RESUMEN

Engineering symmetry breaking in thermoelectric materials holds promise for achieving an optimal thermoelectric efficiency. van der Waals (vdW) layered transition metal dichalcogenides (TMDCs) provide critical opportunities for manipulating the intrinsic symmetry through in-plane symmetry breaking interlayer twists and out-of-plane symmetry breaking heterostructures. Herein, the symmetry-dependent thermoelectric properties of MoS2 and MoSe2 obtained via first-principles calculations are reported, yielding an advanced ZT of 2.96 at 700 K. The underlying mechanisms reveal that the in-plane symmetry breaking results in a lowest thermal conductivity of 1.96 W·m-1·K-1. Additionally, the electric properties can be significantly modulated through band flattening and bandgap alteration, stemming directly from the modified interlayer electronic coupling strength owing to spatial repulsion effects. In addition, out-of-plane symmetry breaking induces band splitting, leading to a decrease in the degeneracy and complex band structures. Consequently, the power factor experiences a notable enhancement from ∼1.32 to 1.71 × 10-2 W·m-1·K-2, which is attributed to the intricate spatial configuration of charge densities and the resulting intensified intralayer electronic coupling. Upon simultaneous implementation of in-plane and out-of-plane symmetry breaking, the TMDCs exhibit an indirect bandgap to direct bandgap transition compared to the pristine structure. This work demonstrates an avenue for optimizing thermoelectric performance of TMDCs through the implementation of symmetry breaking.

18.
Adv Mater ; : e2312964, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39014919

RESUMEN

Bioactive glass (BG) is a class of biocompatible, biodegradable, multifunctional inorganic glass materials, which is successfully used for orthopedic and dental applications, with several products already approved for clinical use. Apart from exhibiting osteogenic properties, BG is also known to be angiogenic and antibacterial. Recently, BG's role in immunomodulation has been gradually revealed. While the therapeutic effect of BG is mostly reported in the context of bone and skin-related regeneration, its application in regenerating other tissues/organs, such as muscle, cartilage, and gastrointestinal tissue, has also been explored recently. The strategies of applying BG have also expanded from powder or cement form to more advanced strategies such as fabrication of composite polymer-BG scaffold, 3D printing of BG-loaded scaffold, and BG-induced extracellular vesicle production. This review presents a concise overview of the recent applications of BG in regenerative medicine. Various regenerative strategies of BG will be first introduced. Next, the applications of BG in regenerating various tissues/organs, such as bone, cartilage, muscle, tendon, skin, and gastrointestinal tissue, will be discussed. Finally, summarizing clinical applications of BG for tissue regeneration will conclude, and outline future challenges and directions for the clinical translation of BG.

19.
Stem Cells Transl Med ; 13(2): 166-176, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-37995322

RESUMEN

Cholangiocytes form a complex 3D network of bile ducts in the liver and contribute to liver function. The damage or destruction of cholangiocytes can lead to biliary diseases, and the shortage of cholangiocytes remains an obstacle for drug development targeting biliary diseases. Valproic acid (VPA) is a potent activator of Notch signaling pathway that is essential for cholangiocyte differentiation. Here, we report a VPA-based approach for cholangiocyte differentiation of human pluripotent stem cells. VPA activated Notch2 expression and upregulated HES-1, HEY-1, and Sox9 gene expression in hESC-derived hepatoblast. After 7 days treatment, VPA promoted successful differentiation of hepatoblast into cholangiocytes expressing cholangiocyte marker genes (AE2, AQP1, CFTR) and proteins (CK19 and CK7). In addition, the differentiated cholangiocytes formed bile duct-like structures after implantation into the spleen of NOD/SCID mice. Our results suggested that VPA can promote hESC differentiation to cholangiocyte-like cells. The induced cholangiocytes may serve as a potential cell source for both in vitro modeling and regenerative therapy of cholangiopathies. The findings can also support further development of small-molecule based differentiation protocols for cholangiocyte production.


Asunto(s)
Células Madre Embrionarias Humanas , Ratones , Animales , Humanos , Ácido Valproico/farmacología , Ratones Endogámicos NOD , Ratones SCID , Células Epiteliales
20.
Biomater Sci ; 12(19): 5036-5051, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39189321

RESUMEN

Diabetic foot ulcers (DFUs) are one of the most serious complications of diabetes, often leading to necrosis and amputation. DFU is caused by the intricate diabetic microenvironment, including ischemia, hypoxia, hyperinflammation, reduced angiogenesis, and persistent infection. Traditional wound dressings made of single or mixed materials often struggle to meet all the requirements for effective diabetic wound healing. In contrast, multilayer dressings comprising more than single layers have the potential to address these challenges by combining their diverse chemical and physical properties. In this study, we developed a bilayer hydrogel comprising a GelMA-ALG-nano-ZnO protective film and a COL1-PRP regenerative hydrogel for facilitating diabetic wound healing. We demonstrated the protective properties against bacterial infection of the protective film, while highlighting the regenerative potential of the COL1-PRP hydrogel in promoting fibroblast and MUVEC migration, extracellular matrix secretion and deposition, and angiogenesis. Importantly, the bilayer hydrogel exhibited superior efficacy in promoting full-thickness wound healing in a diabetic rat model compared to its single-layer hydrogel counterparts. This multi-layer approach offers a promising strategy for addressing the complexities of diabetic foot treatment and improving clinical outcomes.


Asunto(s)
Diabetes Mellitus Experimental , Pie Diabético , Hidrogeles , Ratas Sprague-Dawley , Cicatrización de Heridas , Animales , Cicatrización de Heridas/efectos de los fármacos , Hidrogeles/química , Hidrogeles/farmacología , Hidrogeles/administración & dosificación , Ratas , Pie Diabético/terapia , Pie Diabético/tratamiento farmacológico , Diabetes Mellitus Experimental/complicaciones , Humanos , Masculino , Ratones
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