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Brain metastasis (BM) is one of the leading causes of cancer-related deaths in patients with advanced non-small cell lung cancer (NSCLC). However, limited treatments are available due to the presence of the blood-brain barrier (BBB). Upregulation of lysophosphatidylcholine acyltransferase 1 (LPCAT1) in NSCLC has been found to promote BM. Conversely, downregulating LPCAT1 significantly suppresses the proliferation and metastasis of lung cancer cells. In this study, we firstly confirmed significant upregulation of LPCAT1 in BM sites compared to primary lung cancer by analyzing scRNA dataset. We then designed a delivery system based on a single-chain variable fragment (scFv) targeting the epidermal growth factor receptor (EGFR) and exosomes derived from HEK293T cells to enhance cell-targeting capabilities and increase permeability. Next, we loaded LPCAT1 siRNA (siLPCAT1) into these engineered exosomes (exoscFv). This novel scFv-mounted exosome successfully crossed the BBB in an animal model and delivered siLPCAT1 to the BM site. Silencing LPCAT1 efficiently arrested tumor growth and inhibited malignant progression of BM in vivo without detectable toxicity. Overall, we provided a potential platform based on exosomes for RNA interference (RNAi) therapy in lung cancer BM.
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Neoplasias Encefálicas , Carcinoma Pulmonar de Células não Pequenas , Exossomos , Neoplasias Pulmonares , Animais , Humanos , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/metabolismo , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , RNA Interferente Pequeno/farmacologia , Exossomos/metabolismo , Células HEK293 , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Receptores ErbB/genética , Receptores ErbB/metabolismoRESUMO
Due to the inflammatory responses associated with defect occurrence and materials implantation, immunoregulation has emerged as a promising strategy to enhance bone regeneration. It has been widely reported that a material could facilitate osteogenesis if it can guide macrophages to anti-inflammatory M2 phenotype, vice versa, a substrate will influence macrophage phenotype if it is osteoinductive. However, few studies have looked into the intercellular crosstalking directly. Herein, the compound catalpol was selected for its multiple functions to study the interactions between bone marrow mesenchymal stromal cells (BMSCs) and macrophages. This iridoid glucoside exhibits excellent anti-inflammatory and osteoinductive activities. The effects of catalpol on mediating M1/M2 polarization of macrophages, inhibiting osteoclast differentiation, promoting osteogenesis and angiogenesis were systematically investigated to correlate the biological responses of BMSCs and macrophages. To extend its in vivo application, the catalpol was then loaded onto an electrospun polylactide/gelatin composite fibrous mesh and subcutaneously implanted to evaluate the local inflammation and ectopic osteogenesis. The results revealed that the functions of catalpol displayed in modulating cellular behaviors are via cell paracrine to strengthen intercellular crosstalking, hence demonstrating that catalpol itself could serve as a promising bioactive stimulator for bone tissue engineering.
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Células-Tronco Mesenquimais , Osteogênese , Diferenciação Celular , Glucosídeos Iridoides/farmacologia , MacrófagosRESUMO
Risk-taking differs between humans, and is associated with the personality measures of impulsivity and sensation-seeking. To analyse the brain systems involved, self-report risk-taking, resting state functional connectivity, and related behavioral measures were analyzed in 18,740 participants of both sexes from the UK Biobank. Functional connectivities of the medial orbitofrontal cortex, ventromedial prefrontal cortex (VMPFC), and the parahippocampal areas were significantly higher in the risk-taking group (p < 0.001, FDR corrected). The risk-taking measure was validated in that it was significantly associated with alcohol drinking amount (r = 0.08, p = 5.1×10-28), cannabis use (r = 0.12, p = 6.0×10-66), and anxious feelings (r = -0.12, p = 7.6×-98). The functional connectivity findings were cross-validated in two independent datasets. The higher functional connectivity of the medial orbitofrontal cortex and VMPFC included higher connectivity with the anterior cingulate cortex, which provides a route for these reward-related regions to have a greater influence on action in risk-taking individuals. In conclusion, the medial orbitofrontal cortex, which is involved in reward value and pleasure, was found to be related to risk-taking, which is associated with impulsivity. An implication is that risk-taking is driven by specific orbitofrontal cortex reward systems, and is different for different rewards which are represented differently in the brains of different individuals. This is an advance in understanding the bases and mechanisms of risk-taking in humans, given that the orbitofrontal cortex, VMPFC and anterior cingulate cortex are highly developed in humans, and that risk-taking can be reported in humans.
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Conectoma , Giro do Cíngulo/fisiologia , Comportamento Impulsivo/fisiologia , Giro Para-Hipocampal/fisiologia , Córtex Pré-Frontal/fisiologia , Recompensa , Assunção de Riscos , Adulto , Idoso , Feminino , Giro do Cíngulo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Giro Para-Hipocampal/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagemRESUMO
PURPOSE: The purpose of this study was to identify the incidence, sites and main pathogens, and risk factors for infectious complications occurring in patients with adult acute myeloid leukemia (AML) during the first course of venetoclax combined with decitabine or azacitidine. METHODS: A retrospective cohort analysis was performed of 81 patients with AML older than 14 years who received the first cycle of venetoclax combined with a hypomethylating agent (HMA) between March 2018 and March 2021 at our institution. Infectious complications, if any, were documented. RESULTS: Among a total of 81 cases of AML, 59 (72.8%) patients occurred infections, including fever without an identifiable source (28.8%), clinically documented infections (40.7%), and microbiologically documented infections (30.5%). The most commonly isolated organism in culture was Candida albicans, followed by Klebsiella pneumonia, and Pseudomonas aeruginosa. The 4-week and 8-week mortality rates were 3.7% and 7.4%, respectively. In multivariate analysis, a high proportion of blasts in bone marrow, decreased hemoglobin level, and fever with or without a documented infection at baseline were significant independent risk factors for infectious complications. CONCLUSION: Compared with conventional chemotherapy, the incidence of infectious complications of venetoclax combined with decitabine or azacitidine significantly decreased. Pretreatment high leukemia burden and fever were independent risk factors for infections.
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Azacitidina , Leucemia Mieloide Aguda , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Azacitidina/efeitos adversos , Compostos Bicíclicos Heterocíclicos com Pontes , Decitabina/efeitos adversos , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Estudos Retrospectivos , Sulfonamidas , Resultado do TratamentoRESUMO
BACKGROUND: Periodontitis is characterized by progressive inflammation and alveolar bone loss resulting in tooth loss finally. Macrophages including pro-inflammatory M1-like macrophages and reparative M2-like macrophages play a vital role in inflammation and tissue homeostasis in periodontitis. Among them, reparative M2-like macrophages have been shown to promote tissue repair and prevent bone loss. However, the mechanism of reparative M2 macrophages-induced osteoprotective effect remains elusive. RESULTS: Exosomes from reparative M2-like macrophages (M2-Exos) were isolated and identified successfully. M2-Exos could promote bone marrow stromal cells (BMSCs) osteogenic differentiation while suppressing bone marrow derived macrophage (BMDM) osteoclast formation, and prohibit pathological alveolar bone resorption because of the intercellular communication via exosomes. High expression level of IL-10 mRNA was detected not only in reparative M2-like macrophages but also in M2-Exos. Meanwhile, IL-10 expression level in BMSCs or BMDM was also upregulated significantly after co-culturing with M2-Exos in a concentration-dependent manner. In vitro, recombinant IL-10 proteins had the ability to selectively promote osteogenic differentiation of BMSCs and hinder osteoclast differentiation of BMDM. Moreover, after treatment with M2-Exos and IL-10R antibody together, the capacity of promoting osteogenesis and suppressing osteoclastogenesis of M2-Exos was significantly reversed. In vivo experiments further showed that M2-Exos reduced alveolar bone resorption in mice with periodontitis via IL-10/IL-10R pathway. CONCLUSION: In conclusion, our results demonstrate that the reparative M2-like macrophages could promote osteogenesis while inhibiting osteoclastogenesis in vitro as well as protect alveolar bone against resorption in vivo significantly. M2-Exos could upregulate the IL-10 cytokines expression of BMSCs and BMDM via delivering exosomal IL-10 mRNA to cells directly, leading to activation of the cellular IL-10/IL-10R pathway to regulate cells differentiation and bone metabolism. These results might partly account for the mechanism of osteoprotective effect of reparative M2-like macrophages and provide a novel perspective and a potential therapeutic approach on improving alveolar resorption by M2-Exos.
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Exossomos , Periodontite , Animais , Diferenciação Celular , Exossomos/metabolismo , Interleucina-10/genética , Interleucina-10/metabolismo , Macrófagos/metabolismo , Camundongos , Osteogênese , Periodontite/metabolismo , RNA Mensageiro/metabolismoRESUMO
BACKGROUND: Exosomes are recognized as effective platforms for targeted delivery for their high physicochemical stability and biocompatibility. However, most of the exosomes are inevitably and rapidly cleared by mononuclear phagocytic system (MPS) during cancer therapy. How to engineer exosome to enhance the delivery efficiency is being intensively explored. In this study, we have constructed mPEG2000-TK-CP05 decorated exosomes as effective delivery platforms to achieve enhanced photodynamic/chemical cancer therapy. RESULTS: Exosomes were coated with CP05-TK-mPEG2000, in which CP05 is a peptide with high affinity to exosomal CD63 and TK could be cleaved by ROS. The resulted exosomes, namely stealth Exo, were electroporated to load RB (photosensitizer Rose Bengal) and Dox (Doxorubicin). We verified that the Stealth Exo@RB (Stealth Exo additionally loaded with RB) could escape MPS while accumulate in the tumor region efficiently in the xenograft model when laser irradiation conducted locally. Additionally, we revealed that the Stealth Exo serves as an efficient platform for Dox delivery. Dox, together with the RB mediated photodynamic therapy induce tumor cell damage synergistically in the tumor region. Moreover, the proposed switchable stealth exosomes minimized the dose of toxic Dox and thus allowed robust tumor immune response. CONCLUSIONS: Our results indicated that the proposed Stealth Exo greatly improves both the accessibility and efficiency of drug delivery, with minimal chemical or genetic engineering. The proposed Stealth Exo serve as a promising and powerful drug delivery nanoplatform in cancer treatment.
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Exossomos , Neoplasias , Fotoquimioterapia , Linhagem Celular Tumoral , Doxorrubicina , Sistemas de Liberação de Medicamentos , Humanos , Neoplasias/tratamento farmacológico , Espécies Reativas de OxigênioRESUMO
BACKGROUND: Efficient and topical delivery of drugs is essential for maximized efficacy and minimized toxicity. In this study, we aimed to design an exosome-based drug delivery platform endowed with the ability of escaping from phagocytosis at non-target organs and controllably releasing drugs at targeted location. RESULTS: The swtichable stealth coat CP05-TK-mPEG was synthesized and anchored onto exosomes through the interaction between peptide CP05 and exosomal surface marker CD63. Chlorin e6 (Ce6) was loaded into exosomes by direct incubation. Controllable removal of PEG could be achieved by breaking thioketal (TK) through reactive oxygen species (ROS), which was produced by Ce6 under ultrasound irradiation. The whole platform was called SmartExo. The stealth effects were analyzed in RAW264.7 cells and C57BL/6 mice via tracing the exosomes. To confirm the efficacy of the engineered smart exosomes, Bone morphogenetic protein 7 (Bmp7) mRNA was encapsulated into exosomes by transfection of overexpressing plasmid, followed by stealth coating, with the exosomes designated as SmartExo@Bmp7. Therapeutic advantages of SmartExo@Bmp7 were proved by targeted delivering Bmp7 mRNA to omental adipose tissue (OAT) of obese C57BL/6 mice for browning induction. SmartExo platform was successfully constructed without changing the basic characteristics of exosomes. The engineered exosomes effectively escaped from the phagocytosis by RAW264.7 and non-target organs. In addition, the SmartExo could be uptaken locally on-demand by ultrasound mediated removal of the stealth coat. Compared with control exosomes, SmartExo@Bmp7 effectively delivered Bmp7 mRNA into OAT upon ultrasound irradiation, and induced OAT browning, as evidenced by the histology of OAT and increased expression of uncoupling protein 1 (Ucp1). CONCLUSIONS: The proposed SmartExo-based delivery platform, which minimizes side effects and maximizing drug efficacy, offers a novel safe and efficient approach for targeted drug delivery. As a proof, the SmartExo@Bmp7 induced local white adipose tissue browning, and it would be a promising strategy for anti-obesity therapy.
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Tecido Adiposo Branco , Proteína Morfogenética Óssea 7 , Sistemas de Liberação de Medicamentos/métodos , RNA Mensageiro , Terapia por Ultrassom , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Administração Tópica , Animais , Bioengenharia , Proteína Morfogenética Óssea 7/genética , Proteína Morfogenética Óssea 7/farmacocinética , Proteína Morfogenética Óssea 7/farmacologia , Exossomos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células RAW 264.7 , RNA Mensageiro/genética , RNA Mensageiro/farmacocinética , RNA Mensageiro/farmacologiaRESUMO
Sensation-seeking is a multifaceted personality trait with components that include experience-seeking, thrill and adventure seeking, disinhibition, and susceptibility to boredom, and is an aspect of impulsiveness. We analysed brain regions involved in sensation-seeking in a large-scale study with 414 participants and showed that the sensation-seeking score could be optimally predicted from the functional connectivity with typically (in different participants) 18 links between brain areas (measured in the resting state with fMRI) with correlation r â= â0.34 (p â= â7.3 â× â10-13) between the predicted and actual sensation-seeking score across all participants. Interestingly, 8 of the 11 links that were common for all participants were between the medial orbitofrontal cortex and the anterior cingulate cortex and yielded a prediction accuracy r â= â0.30 (p â= â4.8 â× â10-10). We propose that this important aspect of personality, sensation-seeking, reflects a strong effect of reward (in which the medial orbitofrontal cortex is implicated) on promoting actions to obtain rewards (in which the anterior cingulate cortex is implicated). Risk-taking was found to have a moderate correlation with sensation-seeking (r â= â0.49, p â= â3.9 â× â10-26), and three of these functional connectivities were significantly correlated (p â< â0.05) with the overall risk-taking score. This discovery helps to show how the medial orbitofrontal and anterior cingulate cortices influence behaviour and personality, and indicate that sensation-seeking can involve in part the medial orbitofrontal cortex reward system, which can thereby become associated with risk-taking and a type of impulsiveness.
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Giro do Cíngulo/diagnóstico por imagem , Comportamento Impulsivo , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Sensação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Giro do Cíngulo/fisiologia , Humanos , Comportamento Impulsivo/fisiologia , Masculino , Pessoa de Meia-Idade , Rede Nervosa/fisiologia , Córtex Pré-Frontal/fisiologia , Assunção de Riscos , Sensação/fisiologia , Adulto JovemRESUMO
Cancer-associated cachexia (CAC) has tremendous effects on the patient's tolerance to chemotherapy and the quality of life, especially in the advanced stages, such as the acute and terminal stages of chronic myeloid leukemia (CML). However, the underlying mechanisms and mediators remain unclear. Here, we showed that mice injected with CML-derived exosomes had significant weight loss and great drop of body fat rate. In the meanwhile, we found that CML-derived exosomes could be taken up by adipose tissue, and, in turn, suppressed the adipogenic ability of adipose-derived mesenchymal stem cells (ADSCs). By RNA sequencing, miR-92a-3p was found highly expressed in both CML cells and the derivative exosomes. Mechanistically, miR-92a-3p inhibited adipogenesis of ADSCs via posttranscriptionally decreasing C/EBPα expression when transferred into the ADSCs with the exosomes, and encapsulating miR-92a-3p inhibitor into CML exosomes blocked the antiadipogenic effects of CML exosomes. In addition, we also found that miR-92a-3p was highly expressed in exosomes from some other types of cancers that cause cachexia. These results demonstrate that adipogenesis inhibition by tumor-derived exosomes, mainly exosomal microRNAs like miR-92a-3p, are the main mediators for CAC.
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Adipogenia/fisiologia , Caquexia/etiologia , Exossomos/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/complicações , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/metabolismo , Animais , Caquexia/metabolismo , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Imatinib resistance remains the biggest hurdle for the treatment of chronic myeloid leukemia (CML), with the underlying mechanisms not fully understood. In this study, we found that miR328 significantly and strikingly decreased among other miRNA candidates during the induction of imatinib resistance. Overexpression of miR328 sensitized resistant cells to imatinib via post-transcriptionally decreasing ABCG2 expression, while miR328 knockdown conferred imatinib resistance in parental K562 cells. Moreover, miR328 was found selectively degraded in the lysosomes of K562R cells, as inhibition of lysosome with chloroquine restored miR328 expression and increased sensitivity to imatinib. Moreover, delivery of alkalized exosomes increased endogenous miR328 expression. Compared with the corresponding controls, the alkalized exosomes with or without miR328 sensitized the chronic leukemia cells to imatinib. Taken together, our study has revealed that lysosomal clearance of miR328 in imatinib-resistant cells at least partially contributes to the drug resistance, while delivery of alkalized exosomes would sensitize the chromic leukemia cells to imatinib.
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Antineoplásicos/farmacologia , Exossomos/química , Mesilato de Imatinib/farmacologia , Lisossomos/efeitos dos fármacos , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Álcalis/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo , Células HEK293 , Humanos , Células K562 , Lisossomos/metabolismoRESUMO
FLT3-ITD is a type of poor prognostic factors in acute myeloid leukemia (AML) disease. Gilteritinib, the second-generation FLT3 tyrosine kinase inhibitor, improved the overall survival of patients with relapsed/refractory FLT3-mutated AML in the ADMIRAL phase III trial. However, few data are available on the efficacy and safety of gilteritinib-based therapy for FLT3-mutated AML with central nervous system (CNS) involvement. We performed gilteritinib to treat a patient with CNS relapsed AML after allogeneic hematopoietic stem cell transplantation. The positive antileukemic effect of gilteritinib may bring new hope for the treatment of FLT3-mutated AML with CNS relapse.
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PURPOSE: Microvascular invasion (MVI) is a common complication of hepatocellular carcinoma (HCC) surgery, which is an important predictor of reduced surgical prognosis. This study aimed to develop a fully automated diagnostic model to predict pre-surgical MVI based on four-phase dynamic CT images. METHODS: A total of 140 patients with HCC from two centers were retrospectively included (training set, n = 98; testing set, n = 42). All CT phases were aligned to the portal venous phase, and were then used to train a deep-learning model for liver tumor segmentation. Radiomics features were extracted from the tumor areas of original CT phases and pairwise subtraction images, as well as peritumoral features. Lastly, linear discriminant analysis (LDA) models were trained based on clinical features, radiomics features, and hybrid features, respectively. Models were evaluated by area under curve (AUC), accuracy, sensitivity, specificity, positive and negative predictive values (PPV and NPV). RESULTS: Overall, 86 and 54 patients with MVI- (age, 55.92 ± 9.62 years; 68 men) and MVI+ (age, 53.59 ± 11.47 years; 43 men) were included. Average dice coefficients of liver tumor segmentation were 0.89 and 0.82 in training and testing sets, respectively. The model based on radiomics (AUC = 0.865, 95% CI: 0.725-0.951) showed slightly better performance than that based on clinical features (AUC = 0.841, 95% CI: 0.696-0.936). The classification model based on hybrid features achieved better performance in both training (AUC = 0.955, 95% CI: 0.893-0.987) and testing sets (AUC = 0.913, 95% CI: 0.785-0.978), compared with models based on clinical and radiomics features (p-value < 0.05). Moreover, the hybrid model also provided the best accuracy (0.857), sensitivity (0.875), and NPV (0.917). CONCLUSION: The classification model based on multimodal intra- and peri-tumoral radiomics features can well predict HCC patients with MVI.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Adulto , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Radiômica , Estudos Retrospectivos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Tomografia Computadorizada por Raios XRESUMO
In recent years, cell therapy has provided desirable properties for promising new drugs. Mesenchymal stem cells are promising candidates for developing genetic engineering and drug delivery strategies due to their inherent properties, including immune regulation, homing ability and tumor tropism. The therapeutic potential of mesenchymal stem cells is being investigated for cancer therapy, inflammatory and fibrotic diseases, among others. Mesenchymal stem cells are attractive cellular carriers for synthetic nanoparticles for drug delivery due to their inherent homing ability. In this review, we comprehensively discuss the various genetic and non-genetic strategies of mesenchymal stem cells and their derivatives in drug delivery, tumor therapy, immune regulation, tissue regeneration and other fields. In addition, we discuss the current limitations of stem cell therapy and the challenges in clinical translation, aiming to identify important development areas and potential future directions.
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Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Humanos , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/imunologia , Animais , Sistemas de Liberação de Medicamentos , Neoplasias/terapia , Neoplasias/imunologiaRESUMO
Polymethyl methacrylate (PMMA) based biomaterials have been widely utilized in clinics. However, currently, PMMA catalyzed by benzoyl peroxide (BPO) exhibits disquieting disadvantages including an exothermic polymerization reaction and a lack of bioactivity. Here, we first designed three industrial-scale synthesis methods for high-purity butoxydibutylborane (BODBB), achieving purity levels greater than 95% (maximum: 97.6%) and ensuring excellent fire safety. By utilizing BODBB as a catalyst, the highest polymerization temperature of PMMA bone cement (PMMA-BODBB) reached only 36.05 °C, ensuring that no thermal damage occurred after implantation. Compared to PMMA catalyzed by BPO and partially oxidized tributylborane (TBBO, catalyst of Super Bond C&B), PMMA-BODBB exhibited superior cell adhesion, proliferation, and osteogenesis, attributed to the reduced release of free radicals and toxic monomer, and moderate bioactive boron release. After injection into a 5 mm defect in the rat cranial bone, PMMA-BODBB demonstrated the highest level of osteointegration. This work not only presents an industrial-scale synthesis of high-purity BODBB, but also offers an innovative PMMA biomaterial system with intrinsic biocompatibility and osseointegration, paving the way for the next generation of PMMA-based biomaterials with broader applications.
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Pulmonary fibrosis (PF) is a devastating lung disease with limited treatment options. During this pathological process, the profibrogenic macrophage subpopulation plays a crucial role, making the characterization of this subpopulation fundamentally important. The present study revealed a positive correlation between pulmonary macrophages with higher mitochondrial mass (Mømitohigh) and fibrosis. Among the Mømitohigh subpopulation of CD206+ M2, characterized by higher expression of dynamin 1-like (Drp1), as determined by flow cytometry and RNA-seq analysis, a therapeutic intervention was developed using an exosome-based formula composed of pathfinder and therapeutics. A pathfinder exosome called "exosomeMMP19 (ExoMMP19)", was constructed to display matrix metalloproteinase-19 (MMP19) on the surface to locally break down the excessive extracellular matrix (ECM) in the fibrotic lung. A therapeutic exosome called "exosome therapeutics (ExoTx)", was engineered to display D-mannose on the surface while encapsulating siDrp1 inside. Prior delivery of ExoMMP19 degraded excessive ECM and thus paved the way for ExoTx to be delivered into Mømitohigh, where ExoTx inhibited mitochondrial fission and alleviated PF. This study has not only identified Mømitohigh as profibrotic macrophages but it has also provided a potent strategy to reverse PF via a combination of formulated exosomes.
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Biological receptor-ligand adhesion governed by mammalian cells involves a series of mechanochemical processes that can realize reversible, loading rate-dependent specific interfacial bonding, and even exhibit a counterintuitive behavior called catch bonds that tend to have much longer lifetimes when larger pulling forces are applied. Inspired by these catch bonds, we designed a hydrogen bonding-meditated hydrogel made from acrylic acid-N-acryloyl glycinamide (AA-NAGA) copolymers and tannic acids (TA), which formed repeatable specific adhesion to polar surfaces in an ultra-fast and robust way, but hardly adhered to nonpolar materials. It demonstrated up to five-fold increase in shear adhesive strength and interfacial adhesive toughness with external loading rates varying from 5 to 500 mm min-1. With a mechanochemical coupling model based on Monte Carlo simulations, we quantitatively revealed the nonlinear dependence of rate-sensitive interfacial adhesion on external loading, which was in good agreement with the experimental data. Likewise, the developed hydrogels were biocompatible, possessed antioxidant and antibacterial properties and promoted wound healing. This work not only reports a stimuli-responsive hydrogel adhesive suitable for multiple biomedical applications, but also offers an innovative strategy for bionic designs of smart hydrogels with loading rate-sensitive specific adhesion for various emerging areas including flexible electronics and soft robotics.
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The design of a scaffold that can regulate the sequential differentiation of bone marrow mesenchymal stromal cells (BMSCs) according to the endochondral ossification (ECO) mechanism is highly desirable for effective bone regeneration. In this study, we successfully fabricated a dual-networked composite hydrogel composed of gelatin and hyaluronic acid (termed GCDH-M), which can sequentially release chondroitin sulfate (CS) and magnesium/silicon (Mg/Si) ions to provide spatiotemporal guidance for chondrogenesis, angiogenesis, and osteogenesis. The fast release of CS is from the GCDH hydrogel, and the sustained releases of Mg/Si ions are from poly(lactide-co-glycolide) microspheres embedded in the hydrogel. There is a difference in the release rates between CS and ions, resulting in the ability for the fast release of CS and sustained release of ions. The dual networks between the modified gelatin and hyaluronic acid via covalent bonding and host-guest interactions render the hydrogel with some dynamic feature to meet the differentiation development of BMSCs laden inside the hydrogel, i.e., transforming into a chondrogenic phenotype, further to a hypertrophic phenotype and eventually to an osteogenic phenotype. As evidenced by the results of in vitro and in vivo evaluations, this GCDH-M composite hydrogel was proved to be able to create an optimal microenvironment for embedded BMSCs responding to the sequential guiding signals, which aligns with the rhythm of the ECO process and ultimately boosts bone regeneration. The promising outcome achieved with this innovative hydrogel system sheds light on novel scaffold design targeting bone tissue engineering.