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1.
Cell ; 187(10): 2521-2535.e21, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38697107

RESUMO

Cancer immunotherapy remains limited by poor antigenicity and a regulatory tumor microenvironment (TME). Here, we create "onion-like" multi-lamellar RNA lipid particle aggregates (LPAs) to substantially enhance the payload packaging and immunogenicity of tumor mRNA antigens. Unlike current mRNA vaccine designs that rely on payload packaging into nanoparticle cores for Toll-like receptor engagement in immune cells, systemically administered RNA-LPAs activate RIG-I in stromal cells, eliciting massive cytokine/chemokine response and dendritic cell/lymphocyte trafficking that provokes cancer immunogenicity and mediates rejection of both early- and late-stage murine tumor models. In client-owned canines with terminal gliomas, RNA-LPAs improved survivorship and reprogrammed the TME, which became "hot" within days of a single infusion. In a first-in-human trial, RNA-LPAs elicited rapid cytokine/chemokine release, immune activation/trafficking, tissue-confirmed pseudoprogression, and glioma-specific immune responses in glioblastoma patients. These data support RNA-LPAs as a new technology that simultaneously reprograms the TME while eliciting rapid and enduring cancer immunotherapy.


Assuntos
Imunoterapia , Microambiente Tumoral , Animais , Imunoterapia/métodos , Camundongos , Cães , Humanos , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Citocinas/metabolismo , Glioblastoma/terapia , Glioblastoma/imunologia , Camundongos Endogâmicos C57BL , Feminino , Glioma/terapia , Glioma/imunologia , Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/uso terapêutico , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , RNA/metabolismo , RNA/uso terapêutico , Linhagem Celular Tumoral , Neoplasias/terapia , Neoplasias/imunologia , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/imunologia
2.
Nat Commun ; 15(1): 3741, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702301

RESUMO

Targeted therapy is effective in many tumor types including lung cancer, the leading cause of cancer mortality. Paradigm defining examples are targeted therapies directed against non-small cell lung cancer (NSCLC) subtypes with oncogenic alterations in EGFR, ALK and KRAS. The success of targeted therapy is limited by drug-tolerant persister cells (DTPs) which withstand and adapt to treatment and comprise the residual disease state that is typical during treatment with clinical targeted therapies. Here, we integrate studies in patient-derived and immunocompetent lung cancer models and clinical specimens obtained from patients on targeted therapy to uncover a focal adhesion kinase (FAK)-YAP signaling axis that promotes residual disease during oncogenic EGFR-, ALK-, and KRAS-targeted therapies. FAK-YAP signaling inhibition combined with the primary targeted therapy suppressed residual drug-tolerant cells and enhanced tumor responses. This study unveils a FAK-YAP signaling module that promotes residual disease in lung cancer and mechanism-based therapeutic strategies to improve tumor response.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares , Transdução de Sinais , Fatores de Transcrição , Proteínas de Sinalização YAP , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas de Sinalização YAP/metabolismo , Linhagem Celular Tumoral , Animais , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Neoplasia Residual , Camundongos , Quinase 1 de Adesão Focal/metabolismo , Quinase 1 de Adesão Focal/genética , Receptores ErbB/metabolismo , Receptores ErbB/genética , Quinase do Linfoma Anaplásico/metabolismo , Quinase do Linfoma Anaplásico/genética , Quinase do Linfoma Anaplásico/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Nat Commun ; 15(1): 4160, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755128

RESUMO

The regeneration of critical-size bone defects, especially those with irregular shapes, remains a clinical challenge. Various biomaterials have been developed to enhance bone regeneration, but the limitations on the shape-adaptive capacity, the complexity of clinical operation, and the unsatisfied osteogenic bioactivity have greatly restricted their clinical application. In this work, we construct a mechanically robust, tailorable and water-responsive shape-memory silk fibroin/magnesium (SF/MgO) composite scaffold, which is able to quickly match irregular defects by simple trimming, thus leading to good interface integration. We demonstrate that the SF/MgO scaffold exhibits excellent mechanical stability and structure retention during the degradative process with the potential for supporting ability in defective areas. This scaffold further promotes the proliferation, adhesion and migration of osteoblasts and the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in vitro. With suitable MgO content, the scaffold exhibits good histocompatibility, low foreign-body reactions (FBRs), significant ectopic mineralisation and angiogenesis. Skull defect experiments on male rats demonstrate that the cell-free SF/MgO scaffold markedly enhances bone regeneration of cranial defects. Taken together, the mechanically robust, personalised and bioactive scaffold with water-responsive shape-memory may be a promising biomaterial for clinical-size and irregular bone defect regeneration.


Assuntos
Materiais Biocompatíveis , Regeneração Óssea , Fibroínas , Magnésio , Células-Tronco Mesenquimais , Osteogênese , Alicerces Teciduais , Fibroínas/química , Fibroínas/farmacologia , Regeneração Óssea/efeitos dos fármacos , Animais , Alicerces Teciduais/química , Masculino , Osteogênese/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Ratos , Magnésio/química , Magnésio/farmacologia , Materiais Biocompatíveis/química , Osteoblastos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Ratos Sprague-Dawley , Água/química , Proliferação de Células/efeitos dos fármacos , Engenharia Tecidual/métodos , Crânio/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Bombyx
4.
Actas Esp Psiquiatr ; 52(1): 28-36, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38454900

RESUMO

BACKGROUND: Depressive disorder is a chronic mental illness characterized by persistent low mood as its primary clinical symptom. Currently, psychotherapy and drug therapy stand as the primary treatment modalities in clinical practice, offering a certain degree of relief from negative emotions for patients. Nevertheless, sole reliance on drug therapy exhibits a delayed impact on neurotransmitters, and long-term usage often results in adverse side effects such as nausea, drowsiness, and constipation, significantly impeding medication adherence. This study aims to investigate the impact of combining transcranial magnetic stimulation with sertraline on the cognitive level, inflammatory response, and neurological function in patients with depressive disorder who engage in non-suicidal self-injury (NSSI) behavior. METHODS: A total of 130 depressive patients NSSI behavior, who were admitted to our hospital from December 2020 to February 2023, were selected as the subjects for this research. The single-group (65 cases) received treatment with oral sertraline hydrochloride tablets, while the combination group (65 cases) underwent repetitive transcranial magnetic stimulation (rTMS) in conjunction with sertraline. The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) was utilized to assess the depression status and cognitive function levels of both groups. Additionally, the enzyme-linked immunosorbent assay (ELISA) was employed to measure serum levels of inflammatory factors, including tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6). Furthermore, serum levels of neurotransmitters (norepinephrine (NE), dopamine (DA), 5-hydroxytryptamine (5-HT)) and neuro-cytokines (brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), glial fibrillary acidic protein (GFAP)) were assessed. The clinical effects of the interventions on both groups were then evaluated. RESULTS: Following the treatment, the combination group exhibited significantly higher levels of immediate memory, delayed memory, attention, visual function, and language function compared to the single group, with statistically significant differences (p < 0.05). Additionally, the serum levels of TNF-α, IL-1ß, IL-6, and GFAP in the combination group were lower than those in the single group, while the levels of BDNF and NGF were higher in the combination group compared to the single group. These differences were also statistically significant (p < 0.05). Simultaneously, the total clinical effective rate in the combination group reached 95.38%, surpassing the 84.61% observed in the single group, and the disparity between the two groups was statistically significant (p < 0.05). CONCLUSIONS: The combined use of rTMS and sertraline in treating patients with depressive disorder exhibiting NSSI behavior has proven to be effective in enhancing cognitive function, mitigating inflammatory responses, and elevating levels of neurotransmitters and nerve cytokines in the patients.


Assuntos
Transtorno Depressivo , Comportamento Autodestrutivo , Humanos , Sertralina/uso terapêutico , Estimulação Magnética Transcraniana/métodos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator de Necrose Tumoral alfa , Interleucina-6 , Fator de Crescimento Neural , Citocinas/metabolismo , Cognição , Neurotransmissores
5.
Cell Syst ; 15(2): 166-179.e7, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38335954

RESUMO

Protein clustering plays numerous roles in cell physiology and disease. However, protein oligomers can be difficult to detect because they are often too small to appear as puncta in conventional fluorescence microscopy. Here, we describe a fluorescent reporter strategy that detects protein clusters with high sensitivity called CluMPS (clusters magnified by phase separation). A CluMPS reporter detects and visually amplifies even small clusters of a binding partner, generating large, quantifiable fluorescence condensates. We use computational modeling and optogenetic clustering to demonstrate that CluMPS can detect small oligomers and behaves rationally according to key system parameters. CluMPS detected small aggregates of pathological proteins where the corresponding GFP fusions appeared diffuse. CluMPS also detected and tracked clusters of unmodified and tagged endogenous proteins, and orthogonal CluMPS probes could be multiplexed in cells. CluMPS provides a powerful yet straightforward approach to observe higher-order protein assembly in its native cellular context. A record of this paper's transparent peer review process is included in the supplemental information.


Assuntos
Fenômenos Fisiológicos Celulares , Proteínas , Microscopia de Fluorescência
7.
Actas esp. psiquiatr ; 52(1): 28-36, Feb. 2024. tab
Artigo em Inglês | IBECS | ID: ibc-231254

RESUMO

Background: Depressive disorder is a chronic mental illness characterized by persistent low mood as its primary clinical symptom. Currently, psychotherapy and drug therapy stand as the primary treatment modalities in clinical practice, offering a certain degree of relief from negative emotions for patients. Nevertheless, sole reliance on drug therapy exhibits a delayed impact on neurotransmitters, and long-term usage often results in adverse side effects such as nausea, drowsiness, and constipation, significantly impeding medication adherence. This study aims to investigate the impact of combining transcranial magnetic stimulation with sertraline on the cognitive level, inflammatory response, and neurological function in patients with depressive disorder who engage in non-suicidal self-injury (NSSI) behavior. Methods: A total of 130 depressive patients NSSI behavior, who were admitted to our hospital from December 2020 to February 2023, were selected as the subjects for this research. The single-group (65 cases) received treatment with oral sertraline hydrochloride tablets, while the combination group (65 cases) underwent repetitive transcranial magnetic stimulation (rTMS) in conjunction with sertraline. The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) was utilized to assess the depression status and cognitive function levels of both groups. Additionally, the enzyme-linked immunosorbent assay (ELISA) was employed to measure serum levels of inflammatory factors, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6). Furthermore, serum levels of neurotransmitters (norepinephrine (NE), dopamine (DA), 5-hydroxytryptamine (5-HT)) and neuro-cytokines (brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), glial fibrillary acidic protein (GFAP)) were assessed. The clinical effects of the interventions on both groups were then evaluated. Results: ... (AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Estimulação Magnética Transcraniana , Sertralina/uso terapêutico , Comportamento Autodestrutivo/tratamento farmacológico , Transtorno Depressivo/tratamento farmacológico , Doenças do Sistema Nervoso/tratamento farmacológico
8.
Proc Natl Acad Sci U S A ; 120(37): e2305380120, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37669372

RESUMO

Proactively programming materials toward target nonlinear mechanical behaviors is crucial to realize customizable functions for advanced devices and systems, which arouses persistent explorations for rapid and efficient inverse design strategies. Herein, we propose a "mechanical Fourier transform" strategy to program mechanical behaviors of materials by mimicking the concept of Fourier transform. In this strategy, an arbitrary target force-displacement curve is decomposed into multiple cosine curves and a constant curve, each of which is realized by a rationally designed multistable module in an array-structured metamaterial. Various target curves with distinct shapes can be rapidly programmed and reprogrammed through only amplitude modulation on the modules. Two exemplary metamaterials are demonstrated to validate the strategy with a macroscale prototype based on magnet lattice and a microscale prototype based on an etched silicon wafer. This strategy applies to a variety of scales, constituents, and structures, and paves a way for the property programming of materials.

9.
Environ Sci Pollut Res Int ; 30(44): 99830-99841, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37615912

RESUMO

The controllable preparation of efficient non-crystalline solid solution catalysts is a great challenge in the catalytic oxidation of volatile organic compounds. In this work, series non-crystalline solid solution structured Ce-Mn co-oxide nanofibers were creatively prepared by adjusting Ce/Mn molar ratios using electrospinning. 0.20CeMnOx (the ratio of Ce to Mn was 0.2) displayed an outstanding low-temperature toluene oxidation activity (T90 = 233 °C). The formation of the amorphous solid solution and the unique nanofiber structure both contributed to a large specific surface area (S = 173 m2 g-1) and high adsorbed oxygen content (Oads/O = 41.3%), which enhanced the number of active oxygen vacancies. The synergies between non-crystalline structure and active oxygen species markedly improved oxygen migration rate as well as redox ability of the catalysts. Additionally, in situ diffuse reflectance infrared Fourier transform spectra showed that the absorbed toluene could be completely oxidized to CO2 and H2O with benzyl alcohol, benzaldehyde, benzoic acid, and maleic anhydride as intermediates. In summary, this study provided an alternative route for the synthesis of non-crystalline metal co-oxide nanofibers.


Assuntos
Nanofibras , Óxidos , Óxidos/química , Temperatura , Oxigênio/química , Tolueno/química , Catálise
10.
Int J Mol Sci ; 24(15)2023 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-37569866

RESUMO

Biomechanical forces are of fundamental importance in biology, diseases, and medicine. Mechanobiology is an emerging interdisciplinary field that studies how biological mechanisms are regulated by biomechanical forces and how physical principles can be leveraged to innovate new therapeutic strategies. This article reviews state-of-the-art mechanobiology knowledge about the yes-associated protein (YAP), a key mechanosensitive protein, and its roles in the development of drug resistance in human cancer. Specifically, the article discusses three topics: how YAP is mechanically regulated in living cells; the molecular mechanobiology mechanisms by which YAP, along with other functional pathways, influences drug resistance of cancer cells (particularly lung cancer cells); and finally, how the mechanical regulation of YAP can influence drug resistance and vice versa. By integrating these topics, we present a unified framework that has the potential to bring theoretical insights into the design of novel mechanomedicines and advance next-generation cancer therapies to suppress tumor progression and metastasis.


Assuntos
Neoplasias Pulmonares , Fatores de Transcrição , Humanos , Fenômenos Biomecânicos , Fatores de Transcrição/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Resistencia a Medicamentos Antineoplásicos
12.
Nat Commun ; 14(1): 1234, 2023 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-36871036

RESUMO

High-performance, fast-growing natural materials with sustainable and functional features currently arouse significant attention. Here, facile processing, involving delignification, in situ hydrothermal synthesis of TiO2 and pressure densification, is employed to transform natural bamboo into a high-performance structural material. The resulting TiO2-decorated densified bamboo exhibits high flexural strength and elastic stiffness, with both properties more than double that of natural bamboo. Real-time acoustic emission reveals the key role of the TiO2 nanoparticles in enhancing the flexural properties. The introduction of nanoscale TiO2 is found to markedly increase the degree of oxidation and the formation of hydrogen bonds in bamboo materials, leading to extensive interfacial failure between the microfibers, a micro-fibrillation process that results in substantial energy consumption and high fracture resistance. This work furthers the strategy of the synthetic reinforcement of fast-growing natural materials, which could lead to the expanded applications of sustainable materials for high-performance structural applications.

13.
medRxiv ; 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36993772

RESUMO

Messenger RNA (mRNA) has emerged as a remarkable tool for COVID-19 prevention but its use for induction of therapeutic cancer immunotherapy remains limited by poor antigenicity and a regulatory tumor microenvironment (TME). Herein, we develop a facile approach for substantially enhancing immunogenicity of tumor-derived mRNA in lipid-particle (LP) delivery systems. By using mRNA as a molecular bridge with ultrapure liposomes and foregoing helper lipids, we promote the formation of 'onion-like' multi-lamellar RNA-LP aggregates (LPA). Intravenous administration of RNA-LPAs mimics infectious emboli and elicits massive DC/T cell mobilization into lymphoid tissues provoking cancer immunogenicity and mediating rejection of both early and late-stage murine tumor models. Unlike current mRNA vaccine designs that rely on payload packaging into nanoparticle cores for toll-like receptor engagement, RNA-LPAs stimulate intracellular pathogen recognition receptors (RIG-I) and reprogram the TME thus enabling therapeutic T cell activity. RNA-LPAs were safe in acute/chronic murine GLP toxicology studies and immunologically active in client-owned canines with terminal gliomas. In an early phase first-in-human trial for patients with glioblastoma, we show that RNA-LPAs encoding for tumor-associated antigens elicit rapid induction of pro-inflammatory cytokines, mobilization/activation of monocytes and lymphocytes, and expansion of antigen-specific T cell immunity. These data support the use of RNA-LPAs as novel tools to elicit and sustain immune responses against poorly immunogenic tumors.

14.
Adv Healthc Mater ; 12(1): e2201588, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36314425

RESUMO

In situ tissue regeneration using cell-free biofunctional scaffolds has been extensively studied as a promising alternative strategy to promote cartilage repair. In this study, a cartilage-biomimetic silk fibroin (SF)-based scaffold with controlled sequential release of two bioactive molecules is developed. Transforming growth factor-ß1 (TGF-ß1) is initially loaded onto the SF scaffolds by physical absorption, which are then successively functionalized with bone marrow mesenchymal stem cells (BMSCs)-specific-affinity peptide (E7) via gradient degradation coating of Silk fibroin Methacryloyl (SilMA)/Hyaluronic acid Methacryloyl (HAMA). Such SF-based scaffolds exhibit excellent structural stability and catilage-like mechanical properties, thus providing a desirable 3D microenvironment for cartilage reconstruction. Furthermore, rapid initial release of E7 during the first few days, followed by slow and sustained release of TGF-ß1 for as long as few weeks, synergistically induced the recruitment of BMSCs and chondrogenic differentiation of them in vitro. Finally, in vivo studies indicate that the implantation of the biofunctional scaffold markedly promote in situ cartilage regeneration in a rabbit cartilage defect model. It is believed that this cartilage-biomimetic biofunctional SF-based scaffold with sequential controlled release of E7 and TGF-ß1 may have a promising potential for improved cartilage tissue engineering.


Assuntos
Materiais Biocompatíveis , Fibroínas , Animais , Coelhos , Materiais Biocompatíveis/farmacologia , Fibroínas/química , Fator de Crescimento Transformador beta1/farmacologia , Alicerces Teciduais/química , Cartilagem , Engenharia Tecidual , Diferenciação Celular , Seda
15.
Biomacromolecules ; 24(1): 332-343, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36562543

RESUMO

Natural fiber-reinforced biocomposites with excellent mechanical and biological properties have attractive prospects for internal medical devices. However, poor interfacial adhesion between natural silk fiber and the polymer matrix has been a disturbing issue for such applications. Herein, rigid-flexible agents, such as polydopamine (PDA) and epoxy soybean oil (ESO), were introduced to enhance the interfacial adhesion between Antheraea pernyi (Ap) silk and a common medical polymer, polycaprolactone (PCL). We compared two strategies of depositing PDA first (Ap-PDA-ESO) and grafting ESO first (Ap-ESO-PDA). The rigid-flexible interfacial agents introduced multiple molecular interactions at the silk-PCL interface. The "Ap-PDA-ESO" strategy exhibited a greater enhancement in interfacial adhesion, and interfacial toughening mechanisms were proposed. This work sheds light on engineering strong and tough silk fiber-based biocomposites for biomedical applications.


Assuntos
Polímeros , Seda , Poliésteres
16.
Int J Bioprint ; 8(4): 596, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36483751

RESUMO

Artificial bone materials are of high demand due to the frequent occurrence of bone damage from trauma, disease, and ageing. Three-dimensional (3D) printing can tailor-make structures and implants based on biomaterial inks, rendering personalized bone medicine possible. Herein, we extrusion-printed 3D silk fibroin (SF) scaffolds using mixed inks from SF and sodium alginate (SA), and post-mineralized various calcium phosphates to make hybrid SF scaffolds. The effects of printing conditions and mineralization conditions on the mechanical properties of SF scaffolds were investigated. The SF scaffolds from ~10 wt% SF ink exhibited a compressive modulus of 240 kPa, which was elevated to ~1600 kPa after mineralization, showing a significant reinforcement effect. Importantly, the mineralized SF 3D scaffolds exhibited excellent MC3T3-E1 cell viability and promoted osteogenesis. The work demonstrates a convenient strategy to fabricate SF-based hybrid 3D scaffolds with bone-mimetic components and desirable mechanical properties for bone tissue engineering.

17.
ACS Appl Mater Interfaces ; 14(41): 46932-46944, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36194850

RESUMO

The poor interfacial adhesion between silk fiber and polyester species remains a critical problem for the optimal mechanical performance of silk-reinforced polyester composites. Here, we investigated in quantitative terms the interfacial properties between natural silk fibers and polycaprolactone (PCL) at nano-, micro-, and macroscales and fabricated continuous silk-PCL composite filaments by melt extrusion and drawing processing of PCL melt at 100, 120, and 140 °C. Bombyx mori (Bm) silk, Antheraea pernyi (Ap) silk, and polyamide6 (PA6) fiber were compared to the composite with PCL. The Ap silk exhibited the highest surface energy, the best wettability, and the largest interfacial shear strength (IFSS) with PCL. The silk-PCL composite from the 120 °C melt processing displayed the highest tensile modulus, implying an optimal temperature for interfacial adhesion. The Raman imaging technique revealed in detail the nature of the physical fusion of the interface phase in these silk- and polyamide-reinforced PCL composites. This work is intended to lay a foundation for the design and processing of robust composites from continuous silk fibers and bioresorbable polyesters for potential structural biomaterials.


Assuntos
Nylons , Seda , Seda/química , Poliésteres/química , Materiais Biocompatíveis/química
18.
Sci Adv ; 8(41): eabo6043, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36223455

RESUMO

Spider silks are among the toughest known materials and thus provide models for renewable, biodegradable, and sustainable biopolymers. However, the entirety of their diversity still remains elusive, and silks that exceed the performance limits of industrial fibers are constantly being found. We obtained transcriptome assemblies from 1098 species of spiders to comprehensively catalog silk gene sequences and measured the mechanical, thermal, structural, and hydration properties of the dragline silks of 446 species. The combination of these silk protein genotype-phenotype data revealed essential contributions of multicomponent structures with major ampullate spidroin 1 to 3 paralogs in high-performance dragline silks and numerous amino acid motifs contributing to each of the measured properties. We hope that our global sampling, comprehensive testing, integrated analysis, and open data will provide a solid starting point for future biomaterial designs.

19.
Adv Mater ; 34(47): e2205614, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36120809

RESUMO

Native arteries contain a distinctive intima-media composed of organized elastin and an adventitia containing mature collagen fibrils. In contrast, implanted biodegradable small-diameter vascular grafts do not present spatially regenerated, organized elastin. The elastin-containing structures within the intima-media region encompass the elastic lamellae (EL) and internal elastic lamina (IEL) and are crucial for normal arterial function. Here, the development of a novel electrospun small-diameter vascular graft that facilitates de novo formation of a structurally appropriate elastin-containing intima-media region following implantation is described. The graft comprises a non-porous microstructure characterized by tropoelastin fibers that are embedded in a PGS matrix. After implantation in mouse abdominal aorta, the graft develops distinct cell and extracellular matrix profiles that approximate the native adventitia and intima-media by 8 weeks. Within the newly formed intima-media region there are circumferentially aligned smooth muscle cell layers that alternate with multiple EL similar to that found in the arterial wall. By 8 months, the developed adventitia region contains mature collagen fibrils and the neoartery presents a distinct IEL with thickness comparable to that in mouse abdominal aorta. It is proposed that this new class of material can generate the critically required, organized elastin needed for arterial regeneration.


Assuntos
Prótese Vascular , Elastina , Camundongos , Animais , Miócitos de Músculo Liso , Artérias , Colágeno
20.
PLoS One ; 17(7): e0266098, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35901062

RESUMO

Automatic operations of multi-functional and time-lapse live-cell imaging are necessary for the biomedical science community to study active, multi-faceted, and long-term biological phenomena. To achieve automatic control, most existing solutions often require the purchase of extra software programs and hardware that rely on the manufacturers' own specifications. However, these software programs are usually non-user-programmable and unaffordable for many laboratories. To address this unmet need, we have developed a novel open-source software program, titled Automatic Multi-functional Integration Program (AMFIP), as a new Java-based and hardware-independent system that provides proven advantages over existing alternatives to the scientific community. Without extra hardware, AMFIP enables the functional synchronization of the µManager software platform, the Nikon NIS-Elements platform, and other 3rd party software to achieve automatic operations of most commercially available microscopy systems, including but not limited to those from Nikon. AMFIP provides a user-friendly and programmable graphical user interface (GUI), opening the door to expanding the customizability for myriad hardware and software systems according to user-specific experimental requirements and environments. To validate the intended purposes of developing AMFIP, we applied it to elucidate the question whether single cells, prior to their full spreading, can sense and respond to a soft solid substrate, and if so, how does the interaction depend on the cell spreading time and the stiffness of the substrate. Using a CRISPR/Cas9-engineered human epithelial Beas2B (B2B) cell line that expresses mNeonGreen2-tagged mechanosensitive Yes-associated protein (YAP), we show that single B2B cells develop distinct substrate-stiffness-dependent YAP expressions within 10 hours at most on the substrate, suggesting that cells are able to sense, distinguish, and respond to mechanical cues prior to the establishment of full cell spreading. In summary, AMFIP provides a reliable, open-source, and cost-free solution that has the validated long-term utility to satisfy the need of automatic imaging operations in the scientific community.


Assuntos
Software , Interface Usuário-Computador , Computadores , Humanos , Microscopia
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