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1.
J Cheminform ; 16(1): 76, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956728

RESUMEN

Materials science is an interdisciplinary field that studies the properties, structures, and behaviors of different materials. A large amount of scientific literature contains rich knowledge in the field of materials science, but manually analyzing these papers to find material-related data is a daunting task. In information processing, named entity recognition (NER) plays a crucial role as it can automatically extract entities in the field of materials science, which have significant value in tasks such as building knowledge graphs. The typically used sequence labeling methods for traditional named entity recognition in material science (MatNER) tasks often fail to fully utilize the semantic information in the dataset and cannot effectively extract nested entities. Herein, we proposed to convert the sequence labeling task into a machine reading comprehension (MRC) task. MRC method effectively can solve the challenge of extracting multiple overlapping entities by transforming it into the form of answering multiple independent questions. Moreover, the MRC framework allows for a more comprehensive understanding of the contextual information and semantic relationships within materials science literature, by integrating prior knowledge from queries. State-of-the-art (SOTA) performance was achieved on the Matscholar, BC4CHEMD, NLMChem, SOFC, and SOFC-Slot datasets, with F1-scores of 89.64%, 94.30%, 85.89%, 85.95%, and 71.73%, respectively in MRC approach. By effectively utilizing semantic information and extracting nested entities, this approach holds great significance for knowledge extraction and data analysis in the field of materials science, and thus accelerating the development of material science.Scientific contributionWe have developed an innovative NER method that enhances the efficiency and accuracy of automatic entity extraction in the field of materials science by transforming the sequence labeling task into a MRC task, this approach provides robust support for constructing knowledge graphs and other data analysis tasks.

2.
Nat Commun ; 15(1): 5929, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39009604

RESUMEN

Human iPSC-derived cardiomyocytes (hiPSC-CMs) have proven invaluable for cardiac disease modeling and regeneration. Challenges with quality, inter-batch consistency, cryopreservation and scale remain, reducing experimental reproducibility and clinical translation. Here, we report a robust stirred suspension cardiac differentiation protocol, and we perform extensive morphological and functional characterization of the resulting bioreactor-differentiated iPSC-CMs (bCMs). Across multiple different iPSC lines, the protocol produces 1.2E6/mL bCMs with ~94% purity. bCMs have high viability after cryo-recovery (>90%) and predominantly ventricular identity. Compared to standard monolayer-differentiated CMs, bCMs are more reproducible across batches and have more mature functional properties. The protocol also works with magnetically stirred spinner flasks, which are more economical and scalable than bioreactors. Minor protocol modifications generate cardiac organoids fully in suspension culture. These reproducible, scalable, and resource-efficient approaches to generate iPSC-CMs and organoids will expand their applications, and our benchmark data will enable comparison to cells produced by other cardiac differentiation protocols.


Asunto(s)
Reactores Biológicos , Técnicas de Cultivo de Célula , Diferenciación Celular , Células Madre Pluripotentes Inducidas , Miocitos Cardíacos , Organoides , Humanos , Células Madre Pluripotentes Inducidas/citología , Miocitos Cardíacos/citología , Miocitos Cardíacos/fisiología , Organoides/citología , Técnicas de Cultivo de Célula/métodos , Reproducibilidad de los Resultados , Células Cultivadas , Criopreservación/métodos
3.
Acta Pharmacol Sin ; 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39043970

RESUMEN

Z-discs are core ultrastructural organizers of cardiomyocytes that modulate many facets of cardiac pathogenesis. Yet a comprehensive proteomic atlas of Z-disc-associated components remain incomplete. Here, we established an adeno-associated virus (AAV)-delivered, cardiomyocyte-specific, proximity-labeling approach to characterize the Z-disc proteome in vivo. We found palmdelphin (PALMD) as a novel Z-disc-associated protein in both adult murine cardiomyocytes and human pluripotent stem cell-derived cardiomyocytes. Germline and cardiomyocyte-specific Palmd knockout mice were grossly normal at baseline but exhibited compromised cardiac hypertrophy and aggravated cardiac injury upon long-term isoproterenol treatment. By contrast, cardiomyocyte-specific PALMD overexpression was sufficient to mitigate isoproterenol-induced cardiac injury. PALMD ablation perturbed the transverse tubule (T-tubule)-sarcoplasmic reticulum (SR) ultrastructures, which formed the Z-disc-associated junctional membrane complex (JMC) essential for calcium handling and cardiac function. These phenotypes were associated with the reduction of nexilin (NEXN), a crucial Z-disc-associated protein that is essential for both Z-disc and JMC structures and functions. PALMD interacted with NEXN and enhanced its protein stability while the Nexn mRNA level was not affected. AAV-based NEXN addback rescued the exacerbated cardiac injury in isoproterenol-treated PALMD-depleted mice. Together, this study discovered PALMD as a potential target for myocardial protection and highlighted in vivo proximity proteomics as a powerful approach to nominate novel players regulating cardiac pathogenesis.

4.
Stem Cell Res ; 77: 103427, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38696852

RESUMEN

The DNAJC19 gene, a member of DNAJ heat shock protein (Hsp40) family, is localized within the inner mitochondrial membrane (IMM) and plays a crucial role in regulating the function and localization of mitochondrial Hsp70 (MtHsp70). Mutations in the DNAJC19 gene cause Dilated Cardiomyopathy with Ataxia Syndrome (DCMA). The precise mechanisms underlying the DCMA phenotype caused by DNAJC19 mutations remain poorly understood, and effective treatment modalities were lacking unitl recently. By using CRISPR-Cas9 gene editing technology, this study generated a DNAJC19-knockout (DNAJC19-KO) human embryonic stem cell line (hESC), which will be a useful tool in studying the pathogenesis of DCMA.


Asunto(s)
Sistemas CRISPR-Cas , Proteínas del Choque Térmico HSP40 , Células Madre Embrionarias Humanas , Humanos , Células Madre Embrionarias Humanas/metabolismo , Células Madre Embrionarias Humanas/citología , Proteínas del Choque Térmico HSP40/genética , Proteínas del Choque Térmico HSP40/metabolismo , Técnicas de Inactivación de Genes , Línea Celular , Homocigoto
5.
Int J Pharm ; 656: 124128, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38621612

RESUMEN

Metal-organic frameworks (MOFs) have shown excellent performance in the field of drug delivery. Despite the synthesis of a vast array of MOFs exceeding 100,000 varieties, certain formulations have exhibited suboptimal performance characteristics. Therefore, there is a pressing need to enhance their efficacy by identifying MOFs with superior drug loading capacities and minimal cytotoxicity, which can be achieved through machine learning (ML). In this study, a stacking regression model was developed to predict drug loading capacity and cytotoxicity of MOFs using datasets compiled from various literature sources. The model exhibited exceptional predictive capabilities, achieving R2 values of 0.907 for drug loading capacity and 0.856 for cytotoxicity. Furthermore, various model interpretation methods including partial dependence plots, individual conditional expectation, Shapley additive explanation, decision tree, random forest, CatBoost Regressor, and light gradient-boosting machine were employed for feature importance analysis. The results revealed that specific metal atoms such as Zn, Cr, Fe, Zr, and Cu significantly influenced the drug loading capacity and cytotoxicity of MOFs. Through model validation encompassing experimental validation and computational verification, the reliability of the model was thoroughly established. In general, it is a good practice to use ML methods for predicting drug loading capacity and cytotoxicity analysis of MOFs, guiding the development of future property prediction methods for MOFs.


Asunto(s)
Aprendizaje Automático , Estructuras Metalorgánicas , Estructuras Metalorgánicas/química , Humanos , Supervivencia Celular/efectos de los fármacos , Algoritmos , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos
6.
bioRxiv ; 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38464269

RESUMEN

In the last decade human iPSC-derived cardiomyocytes (hiPSC-CMs) proved to be valuable for cardiac disease modeling and cardiac regeneration, yet challenges with scale, quality, inter-batch consistency, and cryopreservation remain, reducing experimental reproducibility and limiting clinical translation. Here, we report a robust cardiac differentiation protocol that uses Wnt modulation and a stirred suspension bioreactor to produce on average 124 million hiPSC-CMs with >90% purity using a variety of hiPSC lines (19 differentiations; 10 iPSC lines). After controlled freeze and thaw, bioreactor-derived CMs (bCMs) showed high viability (>90%), interbatch reproducibility in cellular morphology, function, drug response and ventricular identity, which was further supported by single cell transcriptomes. bCMs on microcontact printed substrates revealed a higher degree of sarcomere maturation and viability during long-term culture compared to monolayer-derived CMs (mCMs). Moreover, functional investigation of bCMs in 3D engineered heart tissues showed earlier and stronger force production during long-term culture, and robust pacing capture up to 4 Hz when compared to mCMs. bCMs derived from this differentiation protocol will expand the applications of hiPSC-CMs by providing a reproducible, scalable, and resource efficient method to generate cardiac cells with well-characterized structural and functional properties superior to standard mCMs.

7.
Artículo en Inglés | MEDLINE | ID: mdl-38497341

RESUMEN

Bacterial infection and insufficient osteogenic activity are the main causes of orthopedic implant failure. Conventional surface modification methods are difficult to meet the requirements for long-term implant placement. In order to better regulate the function of implant surfaces, especially to improve both the antibacterial and osteogenic activity, external stimuli-responsive (ESR) strategies have been employed for the surface modification of orthopedic implants. External stimuli act as "smart switches" to regulate the surface interactions with bacteria and cells. The balance between antibacterial and osteogenic capabilities of implant surfaces can be achieved through these specific ESR manifestations, including temperature changes, reactive oxygen species production, controlled release of bioactive molecules, controlled release of functional ions, etc. This Review summarizes the recent progress on different ESR strategies (based on light, ultrasound, electric, and magnetic fields) that can effectively balance antibacterial performance and osteogenic capability of orthopedic implants. Furthermore, the current limitations and challenges of ESR strategies for surface modification of orthopedic implants as well as future development direction are also discussed.

8.
J Control Release ; 368: 650-662, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38490374

RESUMEN

Glioblastoma (GBM), deep in the brain, is more challenging to diagnose and treat than other tumors. Such challenges have blocked the development of high-impact therapeutic approaches that combine reliable diagnosis with targeted therapy. Herein, effective cyanine dyes (IRLy) with the near-infrared two region (NIR-II) adsorption and aggregation-induced emission (AIE) have been developed via an "extended conjugation & molecular rotor" strategy for multimodal imaging and phototherapy of deep orthotopic GBM. IRLy was synthesized successfully through a rational molecular rotor modification with stronger penetration, higher signal-to-noise ratio, and a high photothermal conversion efficiency (PCE) up to ∼60%, which can achieve efficient NIR-II photo-response. The multifunctional nanoparticles (Tf-IRLy NPs) were further fabricated to cross the blood-brain barrier (BBB) introducing transferrin (Tf) as a targeting ligand. Tf-IRLy NPs showed high biosafety and good tumor enrichment for GBM in vitro and in vivo, and thus enabled accurate, efficient, and less invasive NIR-II multimodal imaging and photothermal therapy. This versatile Tf-IRLy nanosystem can provide a reference for the efficient, precise and low-invasive multi-synergistic brain targeted photo-theranostics. In addition, the "extended conjugation & molecular rotor" strategy can be used to guide the design of other photothermal agents.


Asunto(s)
Glioblastoma , Nanopartículas , Neoplasias , Humanos , Glioblastoma/diagnóstico por imagen , Glioblastoma/terapia , Fototerapia/métodos , Encéfalo , Barrera Hematoencefálica , Colorantes , Nanomedicina Teranóstica/métodos , Nanopartículas/uso terapéutico , Línea Celular Tumoral
9.
Nat Genet ; 56(3): 420-430, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38378865

RESUMEN

Rare coding mutations cause ∼45% of congenital heart disease (CHD). Noncoding mutations that perturb cis-regulatory elements (CREs) likely contribute to the remaining cases, but their identification has been problematic. Using a lentiviral massively parallel reporter assay (lentiMPRA) in human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs), we functionally evaluated 6,590 noncoding de novo variants (ncDNVs) prioritized from the whole-genome sequencing of 750 CHD trios. A total of 403 ncDNVs substantially affected cardiac CRE activity. A majority increased enhancer activity, often at regions with undetectable reference sequence activity. Of ten DNVs tested by introduction into their native genomic context, four altered the expression of neighboring genes and iPSC-CM transcriptional state. To prioritize future DNVs for functional testing, we used the MPRA data to develop a regression model, EpiCard. Analysis of an independent CHD cohort by EpiCard found enrichment of DNVs. Together, we developed a scalable system to measure the effect of ncDNVs on CRE activity and deployed it to systematically assess the contribution of ncDNVs to CHD.


Asunto(s)
Cardiopatías Congénitas , Células Madre Pluripotentes Inducidas , Humanos , Cardiopatías Congénitas/genética , Secuencias Reguladoras de Ácidos Nucleicos , Mutación , Miocitos Cardíacos
10.
Int J Biol Macromol ; 263(Pt 2): 130368, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38401584

RESUMEN

Surgical resection remains the primary treatment modality for bone tumors. However, it is prone to local bone defects and tumor recurrence. Therefore, there is an urgent need for multifunctional biomaterials that combine tumor treatment and bone repair after bone tumor surgery. Herein, a chitosan composite scaffold (CS/DOX@Ti-MOF) was designed for both tumor therapy and bone repair. Among them, the amino-functionalized Ti-based metal-organic framework (NH2-MIL-125 (Ti), Ti-MOF) has a high specific surface area of 1116 m2/g and excellent biocompatibility, and promotes osteogenic differentiation. The doxorubicin (DOX) loading capacity of Ti-MOF was 322 ± 21 mg/g, and DOX@Ti-MOF has perfect antitumor activity. Furthermore, the incorporation of DOX@Ti-MOF improved the physical and mechanical properties of the composite scaffolds, making the scaffold surface rough and favorable for cells to attach. CS/DOX@Ti-MOF retains the unique properties of each component. It responds to the release of DOX in the tumor microenvironment to remove residual tumor cells, followed by providing a site for cell attachment, proliferation, and differentiation. This promotes bone repair and achieves the sequential treatment of postoperative bone tumors. Overall, CS/DOX@Ti-MOF may be a promising substitute for postoperative bone tumor clearance and bone defect repair. It also provides a possible strategy for postoperative bone tumor treatment.


Asunto(s)
Neoplasias Óseas , Quitosano , Humanos , Osteogénesis , Titanio , Recurrencia Local de Neoplasia , Doxorrubicina/farmacología , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/cirugía , Andamios del Tejido , Microambiente Tumoral
11.
Circulation ; 149(4): 317-329, 2024 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-37965733

RESUMEN

BACKGROUND: Pathogenic variants in SCN5A can result in long QT syndrome type 3, a life-threatening genetic disease. Adenine base editors can convert targeted A T base pairs to G C base pairs, offering a promising tool to correct pathogenic variants. METHODS: We generated a long QT syndrome type 3 mouse model by introducing the T1307M pathogenic variant into the Scn5a gene. The adenine base editor was split into 2 smaller parts and delivered into the heart by adeno-associated virus serotype 9 (AAV9-ABEmax) to correct the T1307M pathogenic variant. RESULTS: Both homozygous and heterozygous T1307M mice showed significant QT prolongation. Carbachol administration induced Torsades de Pointes or ventricular tachycardia for homozygous T1307M mice (20%) but not for heterozygous or wild-type mice. A single intraperitoneal injection of AAV9-ABEmax at postnatal day 14 resulted in up to 99.20% Scn5a transcripts corrected in T1307M mice. Scn5a mRNA correction rate >60% eliminated QT prolongation; Scn5a mRNA correction rate <60% alleviated QT prolongation. Partial Scn5a correction resulted in cardiomyocytes heterogeneity, which did not induce severe arrhythmias. We did not detect off-target DNA or RNA editing events in ABEmax-treated mouse hearts. CONCLUSIONS: These findings show that in vivo AAV9-ABEmax editing can correct the variant Scn5a allele, effectively ameliorating arrhythmia phenotypes. Our results offer a proof of concept for the treatment of hereditary arrhythmias.


Asunto(s)
Trastorno del Sistema de Conducción Cardíaco , Edición Génica , Síndrome de QT Prolongado , Ratones , Animales , Síndrome de QT Prolongado/genética , Síndrome de QT Prolongado/terapia , Síndrome de QT Prolongado/diagnóstico , Arritmias Cardíacas , Miocitos Cardíacos , Adenina , ARN Mensajero , Canal de Sodio Activado por Voltaje NAV1.5/genética , Mutación
12.
bioRxiv ; 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38106146

RESUMEN

Z-lines are core ultrastructural organizers of cardiomyocytes that modulate many facets of cardiac pathogenesis. Yet a comprehensive proteomic atlas of Z-line-associated components remain incomplete. Here, we established an adeno-associated virus (AAV)-delivered, cardiomyocyte-specific, proximity-labeling approach to characterize the Z-line proteome in vivo. We found palmdelphin (PALMD) as a novel Z-line-associated protein in both adult murine cardiomyocytes and human pluripotent stem cell-derived cardiomyocytes. Germline and cardiomyocyte-specific palmd knockout mice were grossly normal at baseline but exhibited compromised cardiac hypertrophy and aggravated cardiac injury upon long-term isoproterenol treatment. By contrast, cardiomyocyte-specific PALMD overexpression was sufficient to mitigate isoproterenol-induced cardiac injury. PALMD ablation perturbed transverse tubules (T-tubules) and their association with sarcoplasmic reticulum, which formed the Z-line-associated junctional membrane complex (JMC) essential for calcium handling and cardiac function. These phenotypes were associated with disrupted localization of T-tubule markers caveolin-3 (CAV3) and junctophilin-2 (JPH2) and the reduction of nexilin (NEXN) protein, a crucial Z-line-associated protein that is essential for both Z-line and JMC structures and functions. PALMD was found to interact with NEXN and enhance its protein stability while the Nexn mRNA level was not affected. Together, this study discovered PALMD as a potential target for myocardial protection and highlighted in vivo proximity proteomics as a powerful approach to nominate novel players regulating cardiac pathogenesis. Highlights: In vivo proximity proteomics uncover novel Z-line components that are undetected in in vitro proximity proteomics in cardiomyocytes.PALMD is a novel Z-line-associated protein that is dispensable for baseline cardiomyocyte function in vivo.PALMD mitigates cardiac dysfunction and myocardial injury after repeated isoproterenol insults.PALMD stabilizes NEXN, an essential Z-line-associated regulator of the junctional membrane complex and cardiac systolic function.

13.
ACS Appl Mater Interfaces ; 15(46): 53217-53227, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37943099

RESUMEN

Bone tumor patients often encounter challenges associated with cancer cell residues and bone defects postoperation. To address this, there is an urgent need to develop a material that can enable tumor treatment and promote bone repair. Metal-organic frameworks (MOFs) have attracted the interest of many researchers due to their special porous structure, which has great potential in regenerative medicine and drug delivery. However, few studies explore MOFs with dual antitumor and bone regeneration properties. In this study, we investigated amino-functionalized zirconium-based MOF nanoparticles (UiO-66-NH2 NPs) as bifunctional nanomaterials for bone tumor treatment and osteogenesis promotion. UiO-66-NH2 NPs loading with doxorubicin (DOX) (DOX@UiO-66-NH2 NPs) showed good antitumor efficacy both in vitro and in vivo. Additionally, DOX@UiO-66-NH2 NPs significantly reduced lung injury compared to free DOX in vivo. Interestingly, the internalized UiO-66-NH2 NPs notably promoted the osteogenic differentiation of preosteoblasts. RNA-sequencing data revealed that PI3K-Akt signaling pathways or MAPK signaling pathways might be involved in this enhanced osteogenesis. Overall, UiO-66-NH2 NPs exhibit dual functionality in tumor treatment and bone repair, making them highly promising as a bifunctional material with broad application prospects.


Asunto(s)
Neoplasias Óseas , Estructuras Metalorgánicas , Nanopartículas , Compuestos Organometálicos , Humanos , Estructuras Metalorgánicas/química , Circonio/química , Osteogénesis , Fosfatidilinositol 3-Quinasas , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Neoplasias Óseas/tratamiento farmacológico
14.
World J Clin Cases ; 11(29): 7214-7220, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37946787

RESUMEN

BACKGROUND: Aggressive angiomyolipoma is an extremely rare benign mesenchymal tumor that was originally described as a locally recurrent mucinous spindle cell tumour. Aggressive angiomyolipoma originates from myofibroblasts, vascular smooth muscle cells, or fibroblasts, and displays various phenotypes of myofibroblasts and abnormal muscle arteries. Aggressive angiomyolipoma was first identified in 1983 and fewer than 50 male patients have been reported to date. It is an extremely rare mesenchymal tumour and often confused with other diseases. Patients with epididymal aggressive angiomyolipoma lack typical symptoms, most of which occur incidentally, although some patients may experience mild pain, discomfort, and swelling. Pain may be exacerbated by pressure from the mass. CASE SUMMARY: A 66-year-old male was admitted to the hospital on January 14, 2022 with chief complaint of swelling in the left scrotum for one year. There was no apparent cause for the swelling. The patient did not consult with any doctor or receive any treatment for the swelling. The enlarged scrotum increased in size gradually until it reached approximately the size of a goose egg, and was accompanied by discomfort and swelling of the left cavity of the scrotum. The patient had no history of any testicular trauma, infection, or urinary tract infection. The patient urinated freely, 1-2 times at night, without urgency, dysuria (painful urination), or haematuria. There was no significant family history of malignancy. The patient underwent excision of the enlarged tumour and the left epididymis under general anaesthesia on January 18, 2022. Twelve months of follow-up revealed no recurrence. The patient was satisfied with the treatment. CONCLUSION: Aggressive angiomyolipoma is extremely rare clinically and often confused with other diseases. The pathogenesis of aggressive angiomyolipoma is unclear and the clinical presentation is mostly a painless enlarged mass. The diagnosis of aggressive angiomyolipoma requires a combination of medical history, preoperative imaging such as computed tomography and magnetic resonance imaging, cytological examination and preoperative and postoperative pathological biopsy. The preferred treatment is surgery, with the possibility of a new alternative treatment option after hormonal therapy. Aggressive angiomyolipoma should be considered in the differential diagnosis of parametrial tumors of the male genital area that present as clinically significant masses. The high recurrence rate of aggressive angiomyolipoma may be related to incomplete tumor resection, and patients with aggressive angiomyolipoma are advised to undergo annual postoperative follow-up and imaging for recurrence.

15.
Langmuir ; 39(42): 15095-15106, 2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37812738

RESUMEN

The detrimental impact of organic contaminants on optical components poses a significant obstacle to high-energy laser systems. However, irregularities or defects on the surface of optical components during manufacturing can affect the process of organic contaminant removal. Thus, a comprehensive understanding of the intricate interplay among surface roughness, contaminant absorption, and ablation is essential to effectively address the challenges of laser-induced damage. In this study, a molecular dynamics approach was employed to investigate the interaction between laser-fused silica and contaminants and to analyze the influence of surface roughness on the removal of contaminants from fused silica. Research findings demonstrate that during laser irradiation, organic contaminants on the surface of mechanical components diffuse into the optical elements. As the laser flux increases, the contaminants gradually decompose into smaller molecular clusters. Additionally, the phenomenon of contaminant ablation is observed to consist of two distinct phases: the "Thermal expansion phase" and the "Thermal ablation phase." The study examines the impact of substrate roughness on the contaminant removal in these two phases. It is found that a higher surface roughness leads to stronger thermal expansion and vaporization of contaminants. With increasing roughness of the fused silica substrate, the corresponding van der Waals energy and pressure decrease under the same laser fluence, making the removal of contaminants easier. These results provide valuable insights into the interaction between laser irradiation and organic contaminants.

18.
Stem Cell Reports ; 18(9): 1811-1826, 2023 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-37595583

RESUMEN

Arrhythmogenic cardiomyopathy (ACM) is an inherited cardiac disorder that causes life-threatening arrhythmias and myocardial dysfunction. Pathogenic variants in Plakophilin-2 (PKP2), a desmosome component within specialized cardiac cell junctions, cause the majority of ACM cases. However, the molecular mechanisms by which PKP2 variants induce disease phenotypes remain unclear. Here we built bioengineered platforms using genetically modified human induced pluripotent stem cell-derived cardiomyocytes to model the early spatiotemporal process of cardiomyocyte junction assembly in vitro. Heterozygosity for truncating variant PKP2R413X reduced Wnt/ß-catenin signaling, impaired myofibrillogenesis, delayed mechanical coupling, and reduced calcium wave velocity in engineered tissues. These abnormalities were ameliorated by SB216763, which activated Wnt/ß-catenin signaling, improved cytoskeletal organization, restored cell junction integrity in cell pairs, and improved calcium wave velocity in engineered tissues. Together, these findings highlight the therapeutic potential of modulating Wnt/ß-catenin signaling in a human model of ACM.


Asunto(s)
Células Madre Pluripotentes Inducidas , Humanos , beta Catenina/genética , Señalización del Calcio , Uniones Intercelulares , Miocitos Cardíacos , Placofilinas/genética
19.
Nat Mater ; 22(8): 1039-1046, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37500957

RESUMEN

Hydrogels are attractive materials for tissue engineering, but efforts to date have shown limited ability to produce the microstructural features necessary to promote cellular self-organization into hierarchical three-dimensional (3D) organ models. Here we develop a hydrogel ink containing prefabricated gelatin fibres to print 3D organ-level scaffolds that recapitulate the intra- and intercellular organization of the heart. The addition of prefabricated gelatin fibres to hydrogels enables the tailoring of the ink rheology, allowing for a controlled sol-gel transition to achieve precise printing of free-standing 3D structures without additional supporting materials. Shear-induced alignment of fibres during ink extrusion provides microscale geometric cues that promote the self-organization of cultured human cardiomyocytes into anisotropic muscular tissues in vitro. The resulting 3D-printed ventricle in vitro model exhibited biomimetic anisotropic electrophysiological and contractile properties.


Asunto(s)
Gelatina , Andamios del Tejido , Humanos , Andamios del Tejido/química , Gelatina/química , Miocitos Cardíacos , Ingeniería de Tejidos/métodos , Hidrogeles/química , Impresión Tridimensional
20.
Colloids Surf B Biointerfaces ; 229: 113445, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37441838

RESUMEN

Chemodynamic therapy (CDT), which converts overexpressed hydrogen peroxide (H2O2) in tumor cells to hydroxyl radicals (•OH) by Fenton reactions, is considered a prospective strategy in anticancer therapy. However, the high level of glutathione (GSH) and poor Fenton catalytic efficiency contribute to the suboptimal efficiency of CDT. Herein, we present a multifunctional nanoplatform (CuFe2O4@HA) that can induce GSH depletion and combine with photothermal therapy (PTT) to enhance antitumor efficacy. CuFe2O4@HA nanoparticles could release Cu2+ and Fe3+ after entering tumor cells by targeting hyaluronic acid (HA). Subsequently, Cu2+ and Fe3+ were reduced to Cu+ and Fe2+ by GSH, where Cu+/Fe2+ significantly catalyzed H2O2 to produce a higher level of •OH, and the depletion of GSH disrupted the antioxidant capacity of the tumor. Therefore, depleting GSH substantially enhances the level of •OH in tumor cells. In addition, CuFe2O4@HA nanoparticles have considerable absorption in the near-infrared (NIR) region, which can stimulate excellent PTT effects. More importantly, the heat generated by PTT can further enhance the Fenton catalysis efficiency. In vitro and in vivo experiments have demonstrated the excellent tumor-killing effect of CuFe2O4@HA nanoparticles. This strategy overcomes the problem of insufficient CDT efficacy caused by GSH overexpression and poor catalytic efficiency. Moreover, this versatile nanoplatform provides a reference for self-enhanced CDT and PTT/CDT synergistic targeted therapy.


Asunto(s)
Ácido Hialurónico , Neoplasias , Humanos , Ácido Hialurónico/farmacología , Peróxido de Hidrógeno , Glutatión , Antioxidantes , Catálisis , Línea Celular Tumoral , Microambiente Tumoral
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