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Highly-efficient and cost-effective electrocatalysts toward the oxygen evolution reaction (OER) are crucial for advancing sustainable energy technologies. Herein, a novel approach leveraging corrosion engineering is presented to facilitate the in situ growth of amorphous cobalt-iron hydroxides on nickel-iron foam (CoFe(OH)x-m/NFF) within a NaCl-CoCl2 aqueous solution. By adjusting the concentration of the solution, the compositions can tailored and morphologies of these hydroxides to optimize the OER electrocatalytic performance. Specifically, the CoFe(OH)x-500/NFF electrode manifests as distinctive 3D flower-like clusters composed of remarkably thin nanosheets, measuring a mere 1 nm in thickness. By virtue of the amorphous and ultrathin nanosheet structure, the CoFe(OH)x-500/NFF electrode exhibits superior OER activity, characterized by notably low overpotentials (η100, 274 mV) and an exceptionally small Tafel slope of 40.54 mV dec-1. Moreover, the electrode's performance remains robust, maintaining low overpotentials for 168 h at 100 mA cm-2. In situ Raman spectroscopy indicates that the hydroxides experience surface structural reconstruction and transform into high-valent CoFeO2 with active Co(IV)-O sites during the OER. Theoretical calculations underscore the critical role of the NiFe substrate in enhancing the electrode's OER activity by improving electrical conductivity and modifying the adsorption energy of reaction intermediates, thereby reducing the energy barrier for the reaction.
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Understanding the dynamics of ion migration and volume change is crucial to studying the functionality and long-term stability of soft polymeric materials operating at liquid interfaces, but the subsurface characterization of swelling processes in these systems remains elusive. In this work, we address the issue using modulated electrochemical atomic force microscopy as a depth-sensitive technique to study electroswelling effects in the high-performance actuator material polypyrrole doped with dodecylbenzenesulfonate (Ppy:DBS). We perform multidimensional measurements combining local electroswelling and electrochemical impedance spectroscopies on microstructured Ppy:DBS actuators. We interpret charge accumulation in the polymeric matrix with a quantitative model, giving access to both the spatiotemporal dynamics of ion migration and the distribution of electroswelling in the electroactive polymer layer. The findings demonstrate a nonuniform distribution of the effective ionic volume in the Ppy:DBS layer depending on the film morphology and redox state. Our findings indicate that the highly efficient actuation performance of Ppy:DBS is caused by rearrangements of the polymer microstructure induced by charge accumulation in the soft polymeric matrix, increasing the effective ionic volume in the bulk of the electroactive film for up to two times the value measured in free water.
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AIMS: To construct a conceptual framework on the process of family resilience during the first year following childhood leukaemia diagnosis. DESIGN: A longitudinal qualitative interview study. METHODS: A longitudinal qualitative study following a grounded theory methodology was employed. Semi-structured interviews were conducted with parents of children with leukaemia in a general hospital. The participants were recruited through purposive and theoretical sampling and longitudinal engagement was achieved by conducting interviews at 1, 3, 6, and 12 months after the leukaemia diagnosis. The core category and categories were saturated following the enrolment of parents of children with leukaemia. Data collection and analyses were performed simultaneously. RESULTS: Sixteen parents of children with leukaemia participated. The core category of 'families living with childhood leukaemia' refers to the process of family resilience during the first year following childhood leukaemia diagnosis, which includes three phases: (1) destruction and resiliency period; (2) adjustment and consolidation period; and (3) growth and planning period. CONCLUSION: This study explored the dynamic, complex and continuous processes of resilience among families coping with childhood leukaemia during the first year following diagnosis. Further research should design tailored family interventions that characterise the different phases of family resilience, aiming to support family well-being, integrity and functioning. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: Both families and healthcare professionals must create an enabling environment that supports families coping with difficulties. Understanding the different phases of family resilience allows healthcare professionals to provide holistic care that meets the demands of families with childhood leukaemia. IMPACT: Unique knowledge emerged about the family's resiliency process when facing childhood leukaemia, suggesting a family-led revolution in understanding and managing childhood leukaemia. Therefore, the development of phased, resilience-based family interventions is imperative. REPORTING METHOD: This study was reported using the COREQ checklist. PATIENT OR PUBLIC CONTRIBUTION: Patients contributed via study participation.
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Background: Patients with cystocele of pelvic organ prolapse quantification (POP-Q) stage II and below can be treated conservatively, but there are few reports on non-surgical treatment for these patients. This study aimed to present the real-world clinical effectiveness of nonsurgical treatment, including pelvic floor muscle training (PFMT), PFMT combined with pessary (PFMT + P), or non-ablative radiofrequency (PFMT + RF) for female with POP-Q stage II cystocele. Methods: We retrospectively analyzed females with POP-Q stage II cystocele between January 2020 and January 2022 who received PFMT, PFMT + P, or PFMT + RF treatment and were followed up for 12 months. Clinical parameters including Pelvic Floor Distress Inventory-20 questionnaire (PFDI-20), Persian version urinary incontinence quality of life questionnaire (I-QOL), POP-Q, pelvic floor Glazer evaluation, and trans-labial ultrasound at different time points were analyzed. Results: There were 147 participants enrolled. PFDI-20 and I-QOL scores were improved in all groups, but the mean decrement in the PFDI-20 scores (-14.28±8.57 and -9.78±8.25) was higher in the PFMT + P group than in the PFMT group and PFMT + RF group at both 6 and 12 months (P<0.05), and the mean I-QOL score (3.82±23.43 and 3.47±22.06) was higher in the PFMT + RP group at both 6 months and 12 months (P<0.05). The PFMT + P group also showed higher improvement rate (43.3%, P=0.03) in terms of changing the severity of cystocele (point Ba) and delta bladder neck-symphyseal distance (ΔBSD) (P<0.05) than the other 2 groups at 12 months. No statistical difference was found in the type-I and type-II myofiber function-based Glazer assessment among 3 groups. Conclusions: The combination of 2 treatment strategies seems to be superior to PFMT only for stage-II cystocele. Specific prolapse-related symptoms and objective indicators did improve more in the PFMT + P group, whereas stress urinary incontinence (SUI) symptoms and quality of life were improved in the PFMT + RP group.
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Objective: This study aims to systematically identify, evaluate, and synthesize published qualitative research on the views and attitudes of adult cancer patients toward telemedicine and, consequently to better inform the future development of telemedicine technology and interventions. Methods: A meta-synthesis review was conducted to identify qualitative studies that reported adult cancer patients' perceptions toward telemedicine applications using nine electronic databases, including PubMed, MEDLINE, Web of Science, the Cochrane Library, PsycINFO, CINAHL, Wan Fang, VIP, and CNKI, from inception to November 2022. Quality appraisal was guided by the Joanna Briggs Institute's (JBI) Critical Appraisal Checklist for Qualitative Research. Data were synthesized using "thematic synthesis" to identify themes and concepts. Results: A total of 3518 articles were retrieved, of which 23 met the inclusion and exclusion criteria. These studies identified three key meta-themes and 11 key sub-themes: (1) Benefits of telemedicine: obtaining information and social support, maintaining the continuity of treatment, receiving professional assistance, having greater flexibility, and promoting physical and mental health; (2) Limitations of telemedicine: interference with normal life, privacy and security issues, auxiliary function issues, and increased psychological burden; (3) Expectations for future telemedicine: more personalized intervention, more specific and diverse information. Conclusions: The study showed that the benefits and limitations coexisted in the process of telemedicine application among adult cancer patients. It is necessary to develop personalized applications that are better suited to the needs and characteristics of adult cancer patients. Future telemedicine interventions should focus on information diversification and provide patients with more diverse and effective information. Systematic review registration: PROSPERO, CRD42022324528.
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BACKGROUND: Children with acute lymphoblastic leukemia often experience various physical and psychological symptoms during chemotherapy. Previous studies have used predetermined symptom inventories to analyze the complex relationships between these symptoms, which has certain limitations. OBJECTIVE: The aim of this study was to explore the dynamic changes in symptom clusters among children with acute lymphoblastic leukemia during chemotherapy using electronic nursing records. METHODS: Electronic nursing records for 2021 (N = 14 490) were obtained from a pediatric hematology department. A natural language processing tool was used to identify the presence of 46 symptoms in 3 chemotherapy phases of induction, consolidation, and maintenance. Incidence of symptom documentation was calculated by notes and patients, and principal component analysis and cluster analysis were performed for symptoms with an incidence above 15%. RESULTS: The most common symptoms included bleeding, cough, and vomiting. The number of symptom clusters in each chemotherapy period was 7, 6, and 4, respectively. There were upper gastrointestinal, respiratory system, lower gastrointestinal, skin-related, psychological, self-image disorder, and other discomfort symptom clusters in the induction period. Notably, the upper gastrointestinal, respiratory system, lower gastrointestinal, and skin-related symptom clusters persisted through the consolidation and maintenance periods. Neurological and other discomfort symptom clusters were observed during the consolidation period. CONCLUSION: Symptom clusters of children with acute lymphoblastic leukemia at various stages of chemotherapy showed a certain level of stability and dynamics, informing healthcare providers in developing continuous symptom management. IMPLICATIONS FOR PRACTICE: Medical staff should explore targeted intervention programs based on characteristics of symptom clusters at different chemotherapy stages, to improve the efficiency of symptom management and alleviate the symptom burden of children.
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AIMS AND OBJECTIVES: To develop a conceptual framework that explores the process of building family resilience among Chinese families with children diagnosed with leukaemia. BACKGROUND: The diagnosis of childhood leukaemia has a devastating effect on the family. Nonetheless, some families were able to positively respond to the crisis. The process through which Chinese families bounce back has received little attention. DESIGN: Grounded theory. METHODS: This study used purposive and theoretical sampling to select 16 parents who agreed to participate in semistructured interviews after children were diagnosed with leukaemia. Data collection and analysis occurred simultaneously. Data were analysed through a process of open, axial and selective coding. The COREQ checklist was followed for reporting. RESULTS: A core category of 'finding family resilience in adversity' was generated. The core category was underpinned by a transition process between two fluid stages: (a) Disrupting the family system, informed by subcategories of negative emotional disturbances and challenges of the diagnosis and treatment journey; (b) Cultivating resilience in families, informed by subcategories of increasing positive attitudes; establishing new family routines; activating good support systems; and practising open family communication. CONCLUSIONS: The transition process from the disruption of the family system to the cultivation of family resilience is perceived as a complex family dynamic in response to childhood leukaemia. Our findings can form the basis for further research about resilience-based family interventions that promote family well-being during the early stages of a childhood leukaemia diagnosis. RELEVANCE TO CLINICAL PRACTICE: It is necessary for healthcare professionals to provide essential support for families to face the challenges of diagnosis and treatment to facilitate the successful transition to family resilience. By understanding the dynamic process of developing family resilience, healthcare professionals are able to focus on these families to provide holistic care that satisfies the specific demands of family members.
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Leucemia , Resiliência Psicológica , Humanos , Criança , Teoria Fundamentada , Saúde da Família , Família/psicologia , Pesquisa QualitativaRESUMO
BACKGROUND: Little is known about how health behaviors cluster to form meaningful patterns that influence health outcomes in young adult nursing students. PURPOSE: The purpose of this study was to identify the unique health behavior patterns among young adult nursing students in China and examine the associations between health behaviors and chronic diseases. METHODS: Using an electronic app, the achievements of an exercise target, sedentary behavior, smoking and drinking, and dietary patterns were assessed in 1,480 nursing student participants aged 18-24 years from two medical universities in Eastern China. RESULTS: A four-class model was developed using latent class analysis that included the "failure to achieve exercise target, alcohol-drinking, and insufficient fruit and vegetable group" (Group 1, n = 187, 12.6%), the "alcohol-drinking and sedentary behavior group" (Group 2, n = 290, 19.6%), the "sedentary behavior only group" (Group 3, n = 721, 48.7%), and the "failure to achieve exercise target only group" (Group 4, n = 282, 19.1%). Logistic regressions indicated that nursing students in Group 2 (odds ratio [ OR ] = 0.42), Group 3 ( OR = 0.51), and Group 4 ( OR = 0.30) were less likely to have chronic diseases than those in Group 1 after adjusting for sociodemographic variables. CONCLUSIONS: The health behaviors were clustered in different patterns among young adult nursing students. Tailoring interventions to specific groups is suggested to improve health outcomes.
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Estudantes de Enfermagem , Adulto Jovem , Humanos , Comportamentos de Risco à Saúde , Análise de Classes Latentes , Universidades , Consumo de Bebidas Alcoólicas , Doença CrônicaRESUMO
BACKGROUND: Circular RNAs (circRNAs) participate in the occurrence and progression of many cancers. CircRNA ataxin 7 (circATXN7) (circBase ID: hsa_circ_0066436) plays a promoting influence on gastric cancer progression. However, the biological role of circATXN7 in non-small cell lung cancer (NSCLC) is indistinct. METHODS: Levels of circATXN7, microRNA (miR)-7-5p, and profilin 2 (PFN2) mRNA were detected using quantitative real-time polymerase chain reaction (RT-qPCR). Proliferation, apoptosis, metastasis, and invasion were analyzed using cell counting kit-8 (CCK-8), colony formation, 5-ethynyl-2'-deoxyuridine (EdU), flow cytometry, and transwell assays. Protein levels were analyzed using western blotting (WB) and immunohistochemistry (IHC). The relationship between circATXN7 or PFN2 and miR-7-5p was analyzed by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. The biological function of circATXN7 was verified by xenograft assay. RESULTS: CircATXN7 and PFN2 were highly expressed in NSCLC, whereas miR-7-5p expression had the opposite trend. CircATXN7 overexpression constrained apoptosis and promoted proliferation, metastasis, invasion, and epithelial-mesenchymal transition of NSCLC cells, but circATXN7 silencing played the opposing influence and repressed xenograft tumor growth in vivo. CircATXN7 served as a miR-7-5p sponge, and circATXN7 regulated malignant behaviors of NSCLC cells through sponging miR-7-5p. PFN2 acted as a miR-7-5p target. PFN2 silencing overturned the promoting effect of miR-7-5p inhibitor on NSCLC cell malignancy, while PFN2 overexpression reversed the inhibitory impact of miR-7-5p mimic on NSCLC cell malignancy. CONCLUSION: CircATXN7 accelerated the malignancy of NSCLC cells through adsorbing miR-7-5p and upregulating PFN2, offering evidence to support circATXN7 as a target for NSCLC treatment.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Ataxina-7/genética , Ataxina-7/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/genética , Regulação para Baixo , Humanos , Neoplasias Pulmonares/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Profilinas/genética , Profilinas/metabolismo , RNA Circular/genéticaRESUMO
Long intergenic non-protein coding RNA 1833 (LINC01833) exhibits elevated expression in the non-small cell lung cancer (NSCLC) tissues, while its molecular mechanism in NSCLC progression remains elusive. Herein, the proliferation, migration, invasion as well as apoptosis of NSCLC cells were assessed. The potential N6-methyladenosine (m6A) modification site was predicted by the m6aVar tool. RNA pulldown and m6A-specific immunoprecipitation assays were used to detect the interaction between LINC01833 and methyltransferase 3, N6-adenosine-methyltransferase complex catalytic subunit (METTL3). RNA pull-down together with mass spectrometry were performed to assess the binding relationship between LINC01833 and heterogeneous nuclear ribonucleoprotein A2/B1 (HNRNPA2B1) in NSCLC. Tumor xenograft mice model was established, and the tumor size and weight were measured. The results demonstrated that LINC01833 expression was elevated in NSCLC samples. Overexpression of LINC01833 promoted proliferative, migratory, and invasive abilities and inhibited HCC827 cell apoptosis. LINC01833 knockdown inhibited tumor growth in mice. LINC01833 is further demonstrated to be modulated by METTL3, which is highly expressed in NSCLC samples. In addition, RNA pulldown and m6A-specific immunoprecipitation assays indicated that LINC01833 might form a complex with HNRNPA2B1. In conclusion, m6A transferase METTL3-induced LINC01833 m6A methylation promotes NSCLC progression through modulating HNRNPA2B1 expression. Our findings indicated that LINC01833 might be a therapeutic target for NSCLC.
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Carcinoma Pulmonar de Células não Pequenas , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B , Neoplasias Pulmonares , RNA Longo não Codificante , Adenosina/análogos & derivados , Adenosina/metabolismo , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Domínio Catalítico , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismo , Humanos , Neoplasias Pulmonares/genética , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismoRESUMO
Osteosarcoma (OS) is one of the most common malignant tumors in adolescents. Due to local invasion, distant metastasis and drug resistance, the clinical treatment efficacy and prognosis of OS have remained almost unchanged for decades. Epigallocatechin-3-gallate (EGCG) is a unique catechin from tea leaves, and some studies have confirmed its antitumour effects on various tumors. Here, cellular experiments showed that EGCG significantly promoted OS cell apoptosis and inhibited proliferation, migration and invasion, and cell and animal experiments demonstrated that the Wnt/ß-catenin pathway played an indispensable role in the antitumour effects of EGCG. Moreover, EGCG inhibited the growth of OS cells in vitro while suppressing tumor cell damage to the bone in situ and distant lung metastasis. The results indicate that the antitumour effect of EGCG on human OS may be mediated by regulating the Wnt/ß-catenin pathway and that EGCG can be used alone or in combination with other regimens as a potentially effective anticancer treatment.
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Neoplasias Ósseas , Catequina , Osteossarcoma , Via de Sinalização Wnt , Animais , Apoptose , Neoplasias Ósseas/tratamento farmacológico , Catequina/análogos & derivados , Catequina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Osteossarcoma/tratamento farmacológico , beta Catenina/metabolismoRESUMO
Although osteosarcoma (OS) is the most common malignant tumor among juvenile bone tumors, its treatment plan and clinical outcome have not improved significantly in recent decades. Tetrandrine (TET), a Chinese medicine that is usually used in the therapy of silicosis, hypertension and arthritis, has been confirmed by many studies to possess potent antitumour growth properties, but there are different limitations when describing specific mechanisms. Here, we found that TET can obviously prevent the proliferation, migration and invasion of both 143B and MG63 cells and promote their apoptosis in vitro. Our results for luciferase reporter and Western blotting assays show that TET may exert its antitumour activity by regulating multiplex signaling pathways, including the MAPK/Erk, PTEN/Akt, Juk and Wnt signaling pathways. Furthermore, the regulatory effect of TET on OS cells and related signaling pathways was verified again in vivo. Our findings suggest that the anticancer function of TET on human OS may be mediated by its targeting of multiple signaling pathways and that TET may be used as a single drug or in combination with other drugs during the treatment of OS.
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Antineoplásicos Fitogênicos/farmacologia , Benzilisoquinolinas/farmacologia , Neoplasias Ósseas/metabolismo , Osteossarcoma/metabolismo , Transdução de Sinais/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , HumanosRESUMO
OBJECTIVES: First-year college students had exposure to unhealthy lifestyle behaviors that correlate with a high prevalence of anxiety and depression. Regarding to the modifiable lifestyle behaviors factors, this study investigated the prevalence and correlation of multiple lifestyle behaviors, anxiety and depression in a sample of Chinese first-year college students. METHODS: Cross-sectional data were extracted from Residents eHealth app of health lifestyle behaviors survey from September to October 2019. Anxiety, depression, eating regular meals, consumption of snacks in-between meals, consumption of fruit, dessert and sugar-sweetened beverages, smoking and secondhand smoke exposure, consuming alcohol, physical activity, sedentary time were assessed by self-report. Socio-demographic including age, gender, education, family income, religion, and health condition were captured. Logistic regression was used to explore the association of multiple lifestyle behaviors, anxiety and depression. RESULTS: Totally 1,017 participants were included in the study. The prevalence of anxiety and depression (from mild to severe) were 40.3% and 45.3%, respectively. In multivariable analyses, religion (believe in Buddhism, OR = 2.438, 95%CI: 1.097-5.421; believe in Christian, OR = 5.886, 95%CI: 1.604-21.597), gender (Female, OR = 1.405, 95%CI: 1.001-1.971), secondhand smoke exposure (OR = 1.089, 95%CI: 1.001-1.184), and eating regular meals (OR = 0.513, 95%CI: 0.346-0.759) were associated with anxiety. Family income (OR = 0.732, 95%CI: 0.596-0.898), eating regular meals (OR = 0.641, 95%CI: 0.415-0.990), frequency of breakfast (OR = 0.813, 95%CI: 0.690-0.959), with a chronic disease (OR = 1.902, 95%CI: 1.335-2.712), and consumption of nocturnal snack (OR = 1.337, 95%CI: 1.108-1.612) were associated with depression. CONCLUSIONS: These results highlighted the need for early lifestyle behavior intervention, especially modifying diet patterns considering the background of religion, health condition, and social-economic status in first-year college students to improve their mental health.
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Mesenchymal stem cells (MSCs) are multipotent progenitors that can differentiate into a variety of cell types under proper stimuli. Bone morphogenetic protein 9 (BMP9) is able to simultaneously induce both adipogenic and osteogenic differentiation of MSCs although the regulatory molecules involved remain to be fully identified and characterized. Heme oxygenase 1 (Hmox1) plays an essential role not only in fat metabolism, but also in bone development. In the present study, we investigated the functional role of Hmox1 in BMP9-induced osteogenic/adipogenic differentiation in MSCs line C3H10T1/2 and probed the possible mechanism involved. We found that BMP9 promoted the endogenous expression of Hmox1 in C3H10T1/2 cells. Overexpression of Hmox1 or cobalt protoporphyrin (CoPP), an inducer of Hmox1, increased BMP9-induced osteogenic differentiation in vitro. Subcutaneous stem cell implantation in nude mice further confirmed that Hmox1 potentiated BMP9-induced ectopic bone formation in vivo. In contrast, Hmox1 reduced BMP9-induced adipogenic differentiation in C3H10T1/2 cells. Although had no obvious effect on BMP9-induced Smad1/5/8 phosphorylation, Hmox1 enhanced phosphorylation of p38, and AKT, while decreased phosphorylation of ERK1/2. Furthermore, Hmox1 increased total ß-catenin protein level, and promoted the nuclear translocation of ß-catenin in C3H10T1/2 cells. Taken together, our study strongly suggests that Hmox1 is likely to potentiate osteogenic differentiation and yet decrease adipogenic differentiation induced by BMP9 possibly through regulation of multiple signaling pathways.
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Adipogenia , Diferenciação Celular , Fator 2 de Diferenciação de Crescimento/metabolismo , Heme Oxigenase-1/metabolismo , Proteínas de Membrana/metabolismo , Células-Tronco Mesenquimais/citologia , Osteogênese , Animais , Células Cultivadas , Feminino , Fator 2 de Diferenciação de Crescimento/genética , Heme Oxigenase-1/genética , Proteínas de Membrana/genética , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Camundongos Nus , Fosforilação , Transdução de SinaisRESUMO
Hydrogels are appealing biomaterials for applications in regenerative medicine due to their tunable physical and bioactive properties. Meanwhile, therapeutic metal ions, such as magnesium ion (Mg2+), not only regulate the cellular behaviors but also stimulate local bone formation and healing. However, the effective delivery and tailored release of Mg2+ remains a challenge, with few reports on hydrogels being used for Mg2+ delivery. Bisphosphonate exhibits a variety of specific bioactivities and excellent binding affinity to multivalent cations such as Mg2+. Herein, we describe a nanocomposite hydrogel based on hyaluronic acid and self-assembled bisphosphonate-magnesium (BP-Mg) nanoparticles. These nanoparticles bearing acrylate groups on the surface not only function as effective multivalent crosslinkers to strengthen the hydrogel network structure, but also promote the mineralization of hydrogels and mediate sustained release of Mg2+. The released Mg2+ ions facilitate stem cell adhesion and spreading on the hydrogel substrates in the absence of cell adhesion ligands, and promote osteogenesis of the seeded hMSCs in vitro. Furthermore, the acellular porous hydrogels alone can support in situ bone regeneration without using exogenous cells and inductive agents, thereby greatly simplifying the approaches of bone regeneration therapy. STATEMENT OF SIGNIFICANCE: In this study, we developed a novel bioactive nanocomposite hydrogel based on hyaluronic acid and self-assembled bisphosphonate-magnesium (BP-Mg) nanoparticles. Such hydrogels are stabilized by the multivalent crosslinking domains formed by the aggregation of Ac-BP-Mg NPs, and therefore show enhanced mechanical properties, improved capacity for mineralization, and controlled release kinetics of Mg2+. Moreover, the released Mg2+ can enhance cell adhesion and spreading, and further promote the osteogenic differentiation of hMSCs. Owing to these unique properties, these acellular hydrogels alone can well facilitate the in vivo bone regeneration at the intended sites. We believe that the strategy reported in this work opens up a new route to develop biopolymer-based nanocomposite hydrogels with enhanced physical and biological functionalities for regenerative medicine.
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Regeneração Óssea/efeitos dos fármacos , Difosfonatos , Hidrogéis , Magnésio , Células-Tronco Mesenquimais/metabolismo , Nanocompostos/química , Crânio , Animais , Difosfonatos/química , Difosfonatos/farmacocinética , Difosfonatos/farmacologia , Humanos , Hidrogéis/química , Hidrogéis/farmacocinética , Hidrogéis/farmacologia , Magnésio/química , Magnésio/farmacocinética , Magnésio/farmacologia , Masculino , Ratos , Ratos Sprague-Dawley , Crânio/lesões , Crânio/metabolismoRESUMO
As one of the least studied bone morphogenetic proteins (BMPs), BMP9 is highly capable of promoting osteogenic differentiation. However, the underlying mechanism involved remains largely unknown. Recent studies have demonstrated that RUNX1 (runt-related transcription factor 1) is essential in osteoblast/chondrocyte maturation. In this study, we investigated the function of RUNX1 in BMP9-induced osteogenic of murine mesenchymal stem cell line (C3H10T1/2) and murine multi-lineage cell lines (C2C12 and MEFs). Our data showed that BMP9 promoted the endogenous expression of RUNX1 in C3H10T1/2, C2C12 and MEFs. Moreover, RUNX1 was probably a direct target of BMP9/Smad signaling. BMP9-induced osteogenic differentiation was enhanced by overexpression of RUNX1, whereas inhibited by knockdown RUNX1 in C3H10T1/2, C2C12 and MEFs. Further mechanism studies demonstrated that RUNX1 might affect BMP9-induced phosphorylation of Smad1/5/8, but not the phosphorylation of p38 and ERK1/2.Our results suggest that RUNX1 may be an essential modulator in BMP9- induced osteogenic differentiation of MSCs (Mesenchymal stem cells).
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Diferenciação Celular , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Fibroblastos/citologia , Fator 2 de Diferenciação de Crescimento/metabolismo , Células-Tronco Mesenquimais/citologia , Mioblastos/citologia , Osteogênese , Animais , Linhagem Celular , Fibroblastos/metabolismo , Células HCT116 , Humanos , Sistema de Sinalização das MAP Quinases , Células-Tronco Mesenquimais/metabolismo , Camundongos , Mioblastos/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismoRESUMO
Recently, hyaluronic acid (HA) hydrogels have been extensively researched for delivering cells and drugs to repair damaged tissues, particularly articular cartilage. However, the in vivo degradation of HA is fast, thus limiting the clinical translation of HA hydrogels. Furthermore, HA cannot bind proteins with high affinity because of the lack of negatively charged sulfate groups. In this study, we conjugated tunable amount of sulfate groups to HA. The sulfated HA exhibits significantly slower degradation by hyaluronidase compared to the wild type HA. We hypothesize that the sulfation reduces the available HA octasaccharide substrate needed for the effective catalytic action of hyaluronidase. Moreover, the sulfated HA hydrogels significantly improve the protein sequestration, thereby effectively extending the availability of the proteinaceous drugs in the hydrogels. In the following in vitro study, we demonstrate that the HA hydrogel sulfation exerts no negative effect on the viability of encapsulated human mesenchymal stem cells (hMSCs). Furthermore, the sulfated HA hydrogels promote the chondrogenesis and suppresses the hypertrophy of encapsulated hMSCs both in vitro and in vivo. Moreover, intra-articular injections of the sulfated HA hydrogels avert the cartilage abrasion and hypertrophy in the animal osteoarthritic joints. Collectively, our findings demonstrate that the sulfated HA is a promising biomaterial for the delivery of therapeutic agents to aid the regeneration of injured or diseased tissues and organs. STATEMENT OF SIGNIFICANCE: In this paper, we conjugated sulfate groups to hyaluronic acid (HA) and demonstrated the slow degradation and growth factor delivery of sulfated HA. Furthermore, the in vitro and in vivo culture of hMSCs laden HA hydrogels proved that the sulfation of HA hydrogels not only promotes the chondrogenesis of hMSCs but also suppresses hypertrophic differentiation of the chondrogenically induced hMSCs. The animal OA model study showed that the injected sulfated HA hydrogels significantly reduced the cartilage abrasion and hypertrophy in the animal OA joints. We believe that this study will provide important insights into the design and optimization of the HA-based hydrogels as the scaffold materials for cartilage regeneration and OA treatment in clinical setting.
Assuntos
Cartilagem Articular/crescimento & desenvolvimento , Condrogênese/fisiologia , Hidrogéis/química , Peptídeos e Proteínas de Sinalização Intercelular/administração & dosagem , Transplante de Células-Tronco Mesenquimais/instrumentação , Células-Tronco Mesenquimais/fisiologia , Osteoartrite do Joelho/terapia , Absorção Fisico-Química , Animais , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/patologia , Células Cultivadas , Condrogênese/efeitos dos fármacos , Terapia Combinada/instrumentação , Terapia Combinada/métodos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/síntese química , Preparações de Ação Retardada/farmacologia , Difusão , Humanos , Ácido Hialurônico/química , Hipertrofia/etiologia , Hipertrofia/patologia , Hipertrofia/prevenção & controle , Peptídeos e Proteínas de Sinalização Intercelular/química , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteoartrite do Joelho/patologia , Osteoartrite do Joelho/fisiopatologia , Ratos , Ratos Sprague-Dawley , Sulfatos/química , Alicerces Teciduais , Resultado do TratamentoRESUMO
Inorganic/organic hybrid scaffolds have great potential for tissue engineering applications due to controllable mechanical properties and tailorable biodegradation. Here, silica/chitosan hybrid scaffolds were fabricated through the sol-gel method with a freeze drying process. 3-Glycidoxypropyl trimethoxysilane (GPTMS) and tetraethylorthosilicate (TEOS) were used as the covalent inorganic/organic coupling agent and the separate inorganic source, respectively. Hybrid scaffolds with various inorganic/organic weight ratios (I/Os) and molar ratios of chitosan and GPTMS (GCs) were examined and compared in this study. FTIR showed that higher GPTMS content resulted in the increased covalent cross-linking of the chitosan and the silica network in hybrids. Compression testing indicated that increasing the GPTMS content greatly improved the compressive strength of scaffold. LIVE/DEAD assay showed that enhanced cytocompatibility was obtained as the silica content increased. Therefore, the results confirmed that the two parameters I/O and GC can largely influence the scaffold performance, which can be used to tailor the hybrid properties.
Assuntos
Quitosana/química , Compostos Orgânicos/química , Dióxido de Silício/química , Alicerces Teciduais/química , Absorção Fisico-Química , Morte Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Força Compressiva , Humanos , Porosidade , Silanos/química , Silício/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse MecânicoRESUMO
Circulating tumor cells (CTC) capture is one of the most effective approaches in diagnosis and treatment of cancers in the field of personalized cancer medicine. In our study, zwitterionic carboxybetaine methacrylate (CBMA) oligomers were grafted onto nylon via atomic transfer random polymerization (ATRP) which would serve as a novel material for the development of convenient CTC capture interventional medical devices. The chemical, physical and biological properties of pristine and modified nylon surfaces were assessed by Fourier transform infrared spectra, atomic force microscope, water contact angle measurements, X-ray photoelectron spectroscopy, protein adsorption, platelet adhesion, and plasma recalcification time (PRT) determinations, etc. The results, including the significant decrease of proteins adsorption and platelets adhesion, as well as prolonged PRTs demonstrated the extraordinary biocompatibility and blood compatibility of the modified surface. Furthermore, we showed that upon immobilization of anti-epithelial cell adhesion molecular (anti-EpCAM) antibody onto the CBMA moiety, the modified nylon surface can selectively capture EpCAM positive tumor cells from blood with high efficiency, indicating the potential of the modified nylon in the manufacture of convenient interventional CTC capture medical devices.
Assuntos
Anticorpos Antineoplásicos/química , Antígenos de Neoplasias/química , Moléculas de Adesão Celular/química , Metacrilatos/química , Proteínas de Neoplasias/química , Células Neoplásicas Circulantes , Nylons/química , Neoplasias Gástricas , Antígenos de Neoplasias/metabolismo , Moléculas de Adesão Celular/metabolismo , Linhagem Celular Tumoral , Molécula de Adesão da Célula Epitelial , Humanos , Proteínas de Neoplasias/metabolismo , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patologia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Neoplasias Gástricas/terapiaRESUMO
Conventional in vitro circulating tumor cell (CTC) detection methods are always limited by blood sample volume because of the requirement of a large amount of blood. The aim of this study was to overcome the limitation by designing and making an in vivo CTC capture device. In this study, we designed and prepared a kind of proper material to serve the purpose of intervention. A method employing 3-aminopropyltriethoxysilane (γ-APS) as the coupling reagent to graft carboxybetaine methacrylate (CBMA) and to immobilize an anti-epithelial cell adhesion molecular (EpCAM) antibody on Nylon was developed. The results of X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy proved the successful graft of γ-APS and CBMA to Nylon. Furthermore, the predicted improvement in the biocompatibilities of our modified Nylon was confirmed by water contact angle measurement, bovine serum albumin adhesion, platelet adhesion, plasma recalcification time determination, and cytotoxicity tests. The tumor cells adhesion experiment revealed that Nylon with the antibody immobilized on it had an affinity for EpCAM positive tumor cells higher than that of pristine Nylon. Additionally, the capture ability of the CTCs was demonstrated in a nude mouse tumor model using the interventional device made of the modified Nylon wire. The positive results suggest that CBMA-grafted and anti-EpCAM antibody-immobilized Nylon is a promising new material for in vivo CTC capture devices.