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1.
Langmuir ; 40(17): 9224-9232, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38630626

RESUMO

Hydrogen is considered clean energy with broad application prospects for the 21st century, and water electrolysis plays a crucial role in hydrogen production. However, economic limitations and large overpotential values hinder its development. In this study, we deposited nickel (Ni), iron (Fe), and sulfur (S) onto nickel foam (NF) using the constant potential method to form the Ni-S-Fe/NF catalyst, which exhibited an exceptionally low overpotential (31 mV) at a current density of -10 mA cm-2, and a Tafel slope of 75.1 mV dec-1 in 1 M sodium hydroxide. It showed a minor charge resistance (1.256 Ω). The amorphous phase structure and optimized catalyst composition promoted outstanding hydrogen evolution activity. This work offers valuable perspectives on the industrial application of hydrogen production.

2.
Langmuir ; 39(22): 7605-7612, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37191156

RESUMO

Hydrogen is a valuable clean energy source, and electrolysis to produce hydrogen from water is a crucial component. However, a major problem of hydrogen generation by electrolysis is its large overpotential and poor economics. To reduce the overpotential, we mainly use nickel foam and Co-Mo ions as feedstock and create an efficient catalytic material by electrodeposition. The Co-Mo interaction improves the current efficiency. In 1 mol/L NaOH solution, the overpotential of the Co-Mo-NF composites was low when the current density is -10 mA/cm2, with the best value reaching 45.3 mV, which is less than those of Co-NF (94.4 mV) and Mo-NF (88.2 mV). All deposits had similar Tafel slopes in the 77.9 mV/decade range. The catalyst does not just have a favorable effect on hydrogen formation but also has a surprisingly high double-layer capacitance (up to 180 mF/cm2) and good stability. This research provides an impactful approach for developing a non-precious metal HER catalyst for industrial hydrogen production.

3.
BMC Geriatr ; 23(1): 457, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37491188

RESUMO

BACKGROUND: The increasing prevalence of Chronic Obstructive Pulmonary Disease (COPD) has imposed a considerable economic burden. However, there remains a paucity of relevant evidence regarding the hospitalization costs of COPD cases. Therefore, in this study, we aimed to assess the hospitalization costs among COPD cases and investigate the factors that contribute to their costs in Henan Province, China. METHODS: We enrolled a total of 1697 cases who were discharged with a diagnosis of COPD from January 1, 2020 to December 31, 2020, into the study. Demographic and clinical characteristics of the cases were obtained from the hospital information system (HIS) of two large tertiary hospitals in Henan Province, China. The factors associated with hospitalization costs were examined using a multiple linear regression model. RESULTS: Total hospitalization costs of 1697 COPD cases were $5,419,011, and the median was $1952 (IQR:2031). Out-of-pocket fees accounted for 43.95% of the total hospitalization costs, and the median was $938 (IQR:956). Multiple linear regression analysis revealed that hospitalization costs were higher among older cases, cases with more comorbidities, and cases with longer length of stay. Furthermore, hospitalization costs were higher in cases who paid through private expenses compared to those covered by Urban Employee Basic Medical Insurance. Additionally, we found that cases admitted through an outpatient clinic had higher hospitalization costs than those admitted through the emergency department. CONCLUSION: Hospitalization costs of COPD cases are substantial. Strategies to reduce hospitalization costs, such as shortening LOS, optimizing payment plans, and preventing or managing complications, should be implemented to alleviate the economic burden associated with COPD hospitalizations.


Assuntos
Hospitalização , Doença Pulmonar Obstrutiva Crônica , Humanos , Centros de Atenção Terciária , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/terapia , Comorbidade , China/epidemiologia , Estudos Retrospectivos
4.
Small ; 18(39): e2203680, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36031402

RESUMO

Precise timing of macrophage polarization plays a pivotal role in immunomodulation of tissue regeneration, yet most studies mainly focus on M2 macrophages for their anti-inflammatory and regenerative effects while the essential proinflammatory role of the M1 phenotype on the early inflammation stage is largely underestimated. Herein, a superparamagnetic hydrogel capable of timely controlling macrophage polarization is constructed by grafting superparamagnetic nanoparticles on collagen nanofibers. The magnetic responsive hydrogel network enables efficient polarization of encapsulated macrophage to the M2 phenotype through the podosome/Rho/ROCK mechanical pathway in response to static magnetic field (MF) as needed. Taking advantage of remote accessibility of magnetic field together with the superparamagnetic hydrogels, a temporal engineered M1 to M2 transition course preserving the essential role of M1 at the early stage of tissue healing, as well as enhancing the prohealing effect of M2 at the middle/late stages is established via delayed MF switch. Such precise timing of macrophage polarization matching the regenerative process of injured tissue eventually leads to optimized immunomodulatory bone healing in vivo. Overall, this study offers a remotely time-scheduled approach for macrophage polarization, which enables precise manipulation of inflammation progression during tissue healing.


Assuntos
Regeneração Óssea , Macrófagos , Colágeno/metabolismo , Humanos , Hidrogéis/farmacologia , Imunomodulação , Inflamação/metabolismo , Macrófagos/metabolismo , Fenótipo
5.
Oral Dis ; 28(8): 2248-2257, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34129722

RESUMO

BACKGROUND AND OBJECTIVE: Host immunity is crucial during periodontal inflammations. B cells are considered to have a function of immunoregulation, and TLRs are considered to be crucial in this process. The present study illustrates the potential roles and rules of CD25+ B cells during periodontitis, especially its effect on regulating host IL-35 level and Th1, Th17, and Treg differentiation. MATERIAL AND METHODS: The proportion of local and systemic CD25+ B cell subpopulations from periodontitis models were identified by flow cytometry. To illustrate further mechanism, B cells were cultured with a different type of TLR activators. Expression of IL-10, IL-35, and TGF-ß was detected by ELISA and real-time PCR. We also set adoptive transfer models by using CD25+ B cells. Alveolar bone erosion, proportion of Th1, Th17, and Tregs, and levels of IFN-γ, TNF-α, IL-1ß, and IL-17 were identified. RESULT: Periodontitis induces more CD25+ B cell subpopulations and promotes their IL-10, IL-35, and TGF-ßproduction. TLR activators enhanced Breg proliferation and function. LPS+CpG obviously induced more CD25+ B cell differentiation and production of IL-10, IL-35, and TGF-ß. Adoptive transfer of CD25+ B cells reduces alveolar bone destruction and local Tregs, proportion, especially the local level of IFN-γ and IL-17. In addition, adoptive transfer of CD25+ B cells remedies the pathological change in the proportion of IL-1ß and Th1/Th17 in local lesions. We did not find any significant difference in peripheral blood, regardless of group and detected items. CONCLUSION: Results of the present study clarify that CD25+ B cells enlarged and produced more IL-10, IL-35 and TGF-ß during periodontitis, activation of TLR4 and TLR9 played crucial roles in this process. Also, CD25+ B cells alleviated periodontal inflammation and alveolar bone resorption. Our findings further expanded the potential of B cells during periodontitis.


Assuntos
Perda do Osso Alveolar , Periodontite , Perda do Osso Alveolar/prevenção & controle , Humanos , Inflamação , Interleucina-10 , Interleucina-17 , Lipopolissacarídeos , Periodontite/metabolismo , Linfócitos T Reguladores/patologia , Receptor 4 Toll-Like , Receptor Toll-Like 9 , Fator de Crescimento Transformador beta , Fator de Necrose Tumoral alfa
6.
Molecules ; 27(10)2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35630685

RESUMO

Peri-implantitis can lead to implant failure. In this study, curcumin (CUR) was modified onto the copper-bearing titanium alloy (Cu-Ti) with the assistance of polydopamine (PDA) in order to study the bone immune response and subsequent osteogenesis. FE-SEM, XPS and water contact angle were utilized to characterize the coating surface. Bone marrow mesenchymal stem cells (BMSCs) and macrophages were cultured separately and together onto the CUR modified Cu-Ti. Cell activity, expression of relative genes and proteins, cell migration ability, and fluorescence staining of cells were performed. CUR modification slightly increased the activation of M1-type and M2-type cells under physiological conditions. In the inflammation state, CUR inhibited the overexpression of M1 macrophages and induced M2-type differentiation. In addition, the modification itself could provoke the expression of osteoblastic-related genes of BMSCs, while promoting the osteogenic differentiation of BMSCs through the activation of macrophages in both physiological and inflammatory states. The BMSCs migration was increased, the expression of osteogenic-related genes and proteins was up-regulated, and alkaline phosphatase activity (ALP) was increased. Thus, the modification of CUR can promote the osteointegration effect of Cu-Ti by bone immunomodulation and may, in addition, improve the success rate of implants.


Assuntos
Curcumina , Titânio , Cobre/farmacologia , Curcumina/farmacologia , Osteogênese , Propriedades de Superfície , Titânio/farmacologia
7.
J Appl Biomed ; 19(2): 97-104, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34907709

RESUMO

Inflammatory imbalance of bone formation/resorption leads to alveolar bone destruction. Astragalus polysaccharide has been confirmed to have anti-inflammatory effects. We sought to disclose the protective effect and its potential mechanisms of astragalus polysaccharide in the periodontitis model. Experimental periodontitis was induced by cotton ligatures for this study. We measured the alveolar bone damage rate, periodontal osteoclasts, proportion of CD4+Foxp3+, CD4+IL-10+, CD4+TGF-ß+ subsets in the gingiva, and RANKL, OPG, TGF-ß+, and IL-10+ level in the gingiva. We also cultured osteoclast precursor cells in the presence of RANKL and astragalus polysaccharide. Osteoclasto-like cells were identified by TRAP staining, mRNA of RANK, TRAP, and TRAF6 were evaluated by real time PCR. We found that astragalus polysaccharide caused significant protection of the alveolar bone via reducing local osteoclasts. It also decreased the proportion of CD4+Foxp3+ cells and upregulated the level of CD4+IL-10+ cells, reduced RANKL, and remedied IL-10 levels. In cell culture experiments, astragalus polysaccharide prohibited the RANKL mediated osteoclast differentiation. The findings of this study disclose the functions and possible mechanisms of astragalus polysaccharide engaged in local osteoclastogenesis, and reveal the considerable effect of astragalus polysaccharide in alveolar bone homeostasis and its likely contribution to host immuno-regulation in periodontitis.


Assuntos
Reabsorção Óssea , Periodontite , Polissacarídeos , Animais , Astrágalo/química , Fatores de Transcrição Forkhead , Interleucina-10 , Osteogênese , Periodontite/tratamento farmacológico , Polissacarídeos/farmacologia , Ratos , Fator de Crescimento Transformador beta
8.
Eur J Nucl Med Mol Imaging ; 47(5): 1275-1280, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32107577

RESUMO

BACKGROUND: The pneumonia caused by the 2019 novel coronavirus (SARS-CoV-2, also called 2019-nCoV) recently break out in Wuhan, China, and was named as COVID-19. With the spread of the disease, similar cases have also been confirmed in other regions of China. We aimed to report the imaging and clinical characteristics of these patients infected with SARS-CoV-2 in Guangzhou, China. METHODS: All patients with laboratory-identified SARS-CoV-2 infection by real-time polymerase chain reaction (PCR) were collected between January 23, 2020, and February 4, 2020, in a designated hospital (Guangzhou Eighth People's Hospital). This analysis included 90 patients (39 men and 51 women; median age, 50 years (age range, 18-86 years). All the included SARS-CoV-2-infected patients underwent non-contrast enhanced chest computed tomography (CT). We analyzed the clinical characteristics of the patients, as well as the distribution characteristics, pattern, morphology, and accompanying manifestations of lung lesions. In addition, after 1-6 days (mean 3.5 days), follow-up chest CT images were evaluated to assess radiological evolution. FINDINGS: The majority of infected patients had a history of exposure in Wuhan or to infected patients and mostly presented with fever and cough. More than half of the patients presented bilateral, multifocal lung lesions, with peripheral distribution, and 53 (59%) patients had more than two lobes involved. Of all included patients, COVID-19 pneumonia presented with ground glass opacities in 65 (72%), consolidation in 12 (13%), crazy paving pattern in 11 (12%), interlobular thickening in 33 (37%), adjacent pleura thickening in 50 (56%), and linear opacities combined in 55 (61%). Pleural effusion, pericardial effusion, and lymphadenopathy were uncommon findings. In addition, baseline chest CT did not show any abnormalities in 21 patients (23%), but 3 patients presented bilateral ground glass opacities on the second CT after 3-4 days. CONCLUSION: SARS-CoV-2 infection can be confirmed based on the patient's history, clinical manifestations, imaging characteristics, and laboratory tests. Chest CT examination plays an important role in the initial diagnosis of the novel coronavirus pneumonia. Multiple patchy ground glass opacities in bilateral multiple lobular with periphery distribution are typical chest CT imaging features of the COVID-19 pneumonia.


Assuntos
Betacoronavirus , Infecções por Coronavirus/diagnóstico por imagem , Pneumonia Viral/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19 , Teste para COVID-19 , China , Técnicas de Laboratório Clínico , Infecções por Coronavirus/complicações , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Tosse/etiologia , Progressão da Doença , Feminino , Febre/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/epidemiologia , SARS-CoV-2 , Tomografia Computadorizada por Raios X , Adulto Jovem
9.
Inorg Chem ; 59(2): 1522-1531, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31913028

RESUMO

The hexagonal copper-tin alloy (Cu-Sn) nanoplates were synthesized using a high temperature solvent method, the length of six equilateral edges of hexagonal Cu-Sn nanoplates was 23 nm, and the thickness was 13 nm. The obtained hexagonal Cu-Sn nanoplates were highly monodisperse and allowed the formation of nanoarrays arranged with long-range order. The hexagonal Cu-Sn nanoplates exhibited high catalytic activity on catalytic hydrogenation of 4-nitrophenol to 4-aminophenol. Due to the promotion effect of Sn, the apparent rate constant (ka) of hexagonal Cu-Sn nanoplates was three times that of Cu nanoparticles. The density functional theory (DFT) calculations and experimental results demonstrated that Sn could promote the coordination process of -NO2 of 4-nitrophenol with Cu-Sn nanoplates and contribute to activation of 4-nitrophenol. In addition, the hexagonal Cu-Sn nanoplates showed high stability and reusability for the reduction reaction, good adaptability in different pH and the ionic strength, and wide applicability for the degradation of methylene blue, methyl orange, and rhodamine B, even in the industrial wastewater, suggesting that the Cu-Sn nanoplates are promising catalysts in organic industry wastewater treatment.

10.
J Am Chem Soc ; 141(44): 17610-17616, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31639300

RESUMO

The ideal charge transport materials should exhibit a proper energy level, high carrier mobility, sufficient conductivity, and excellent charge extraction ability. Here, a novel electron transport material was designed and synthesized by using a simple and facile solvothermal method, which is composed of the core-shell ZnO@SnO2 nanoparticles. Thanks to the good match between the energy level of the SnO2 shell and the high electron mobility of the core ZnO nanoparticles, the PCE of inorganic perovskite solar cells has reached 14.35% (JSC: 16.45 mA cm-2, VOC: 1.11 V, FF: 79%), acting core-shell ZnO@SnO2 nanoparticles as the electron transfer layer. The core-shell ZnO@SnO2 nanoparticles size is 8.1 nm with the SnO2 shell thickness of 3.4 nm, and the electron mobility is seven times more than SnO2 nanoparticles. Meanwhile, the uniform core-shell ZnO@SnO2 nanoparticles is extremely favorable to the growth of inorganic perovskite films. These preliminary results strongly suggest the great potential of this novel electron transfer material in high-efficiency perovskite solar cells.

11.
Med Sci Monit ; 22: 1843-9, 2016 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-27243444

RESUMO

BACKGROUND Cervical disc replacement (CDR) has been widely used to restore and maintain mobility and function of the treated and adjacent motion segments. Posterior longitudinal ligament (PLL) resection has been shown to be efficient in anterior cervical decompression and fusion. However, less is known about the biomechanical effect of PLL removal versus preservation in cervical disc arthroplasty. MATERIAL AND METHODS Three motion segments of 24 ovine cervical spines (C2-C5) were evaluated in a robotic spine system with axial compressive loads of 50 N. These cervical spines were divided in three groups according to the following conditions: (1) intact spine, (2) C3/C4 CDR with the Prestige LP prosthesis and PLL preservation, and (3) C3/C4 CDR with the Prestige LP prosthesis and PLL removal. The ranges of motion (ROMs) were recorded and analyzed in each group. RESULTS The C3/C4 ROM in group 3 (CDR with PLL removed) increased significantly in flexion-extension and axial rotation compared with group 1 (intact spine). Moreover, in flexion-extension, the mean total ROM was significantly larger in group 3 than in group 1. All the ROM observed in group 2 (CDR with PLL preserved) did not significantly differ from the ROM observed in group 1. CONCLUSIONS Compared with intact spines, CDR with PLL removal partly increased ROM. Moreover, the ROM in CDR with PLL preservation did not significantly differ from the ROM observed in intact spines. The PLL appears to contribute to the balance and stability of the cervical spine and should thus be preserved in cervical disc replacement provided that the posterior longitudinal ligament is not degenerative and the compression can be removed without PLL takedown.


Assuntos
Vértebras Cervicais/cirurgia , Ligamentos Longitudinais/fisiologia , Fusão Vertebral/métodos , Substituição Total de Disco , Animais , Artroplastia/métodos , Fenômenos Biomecânicos/fisiologia , Vértebras Cervicais/fisiologia , Descompressão Cirúrgica , Disco Intervertebral/fisiologia , Disco Intervertebral/cirurgia , Modelos Animais , Implantação de Prótese , Amplitude de Movimento Articular/fisiologia , Ovinos
14.
Accid Anal Prev ; 200: 107491, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38489941

RESUMO

Freight truck-related crashes in urban contexts have caused significant economic losses and casualties, making it increasingly essential to understand the spatial patterns of such crashes. Limitations regarding data availability have greatly undermined the generalizability and applicability of certain prior research findings. This study explores the potential of emerging geospatial data to delve deeply into the determinants of these incidents with a more generalizable research design. By synergizing high-resolution satellite imagery with refined GIS map data and geospatial tabular data, a rich tapestry of the road environment and freight truck operations emerges. To navigate the challenges of zero-inflated issues of the crash datasets, the Tweedie Gradient Boosting model is adopted. Results reveal a pronounced spatial heterogeneity between highway and urban non-highway road networks in crash determinants. Factors such as freight truck activity, intricate road network patterns, and vehicular densities rise to prominence, albeit with varying degrees of influence across highways and urban non-highway terrains. Results emphasize the need for context-specific interventions for policymakers, encompassing optimized urban planning, infrastructural overhauls, and refined traffic management protocols. This endeavor may not only elevate the academic discourse around freight truck-related crashes but also champion a data-driven approach towards safer road ecosystems for all.


Assuntos
Acidentes de Trânsito , Ecossistema , Humanos , Acidentes de Trânsito/prevenção & controle , Imagens de Satélites , Veículos Automotores
15.
Mar Environ Res ; 198: 106521, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38678753

RESUMO

Red tide is a marine phenomenon caused by the excessive growth of microscopic algae in the ocean. This study aims to analyze the development trends of red tides in the past 20 years and the dynamic external causes that induce red tides based on existing satellite remote sensing and numerical simulation data. And the changes in dominant species of red tides in different seasons are analyzed. The results show significant temperature fluctuations within the week before the red tide occurs, with an average increase of 1.42 °C. In contrast, the change in salinity is relatively small. Meanwhile, ocean fronts are areas in the ocean where different water masses meet and form boundaries. The average strength of ocean fronts increased by 3.7%, indicating enhanced ocean mixing over a short period of time. Under the combined influence of these factors, the probability of a red tide outbreak in the East China Sea increases rapidly. Therefore, this study has important reference value for further research on the causes of red tides and their response to ocean dynamic changes.


Assuntos
Monitoramento Ambiental , Proliferação Nociva de Algas , Oceanos e Mares , China , Estações do Ano , Água do Mar/química , Salinidade , Temperatura
16.
NPJ Breast Cancer ; 10(1): 74, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39164282

RESUMO

Recent studies have highlighted the potential of ferroptosis in treating breast cancer. However, the efficacy of ferroptosis induction in the most common subtype, estrogen receptor-positive (ER + ) breast cancer, remains inadequately explored. This study unveils that both short-term and long-term treatment with ER-targeted endocrine agents sensitizes ER+ breast cancer cells to ferroptosis inducers, particularly the GPX4 inhibitor, revealing a non-mutational sensitization mechanism. Based on this finding, we introduce a 55-gene signature score (FERscore) tailored to assess ferroptosis susceptibility in breast cancer. Data from cell lines and primary tumors demonstrate significant lower FERscores in ER+ breast cancer compared to other subtypes; however, FERscores dramatically increase in endocrine-resistant ER+ tumor cells and residual tumors post-endocrine therapy. Furthermore, FERscore correlates positively with mesenchymal traits, stemness, immune cell infiltration, and cancer-associated fibroblasts enrichment, while inversely correlating with estrogen responsiveness and DNA repair capacity. Additionally, the FERscore proves effective in predicting therapeutic responses to anti-ER, anti-HER2, poly (ADP-ribose) polymerase inhibitor, and anti-angiogenesis therapies in breast cancer. In summary, ferroptosis induction emerges as a promising avenue in breast cancer therapy. The FERscore offers an innovative tool for identifying patients who may benefit from ferroptosis-inducing therapies, especially those responsive to GPX4 inhibitors.

17.
Chem Sci ; 15(25): 9851-9857, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38939150

RESUMO

Developing electrocatalysts with high activity toward the hydrogen evolution reaction (HER) is a prerequisite for hydrogen fuel generation and sustainable development, but current Pt-based catalysts usually suffer from high cost and unsatisfactory performance in non-acidic media. In this work, we report an environmentally friendly and pyrolysis-free synthesis strategy to prepare an efficient catalyst, CNT-NPA-PtRu, with Pt single-atom engineered sub-nanometric Ru clusters anchored at phytic acid-modified carbon nanotubes for electrochemical HER at all pH conditions. The electronic structure of active sub-nanometric Ru clusters was optimized, which further enhanced the HER activity. The synthesized CNT-NPA-PtRu catalyst presents superior performance, reaching the current density of 10 mA cm-2 with only 18.3, 18.7 and 15 mV overpotential in alkaline, acidic and neutral electrolyte, respectively. Experimental results and theoretical calculations reveal that the single Pt atom on the sub-nanometric Ru cluster surface could modulate the electronic structure of Ru and subsequently optimize the adsorption of reaction intermediates, thus promoting HER performance. These findings underscore the importance of engineering the electronic structure of sub-nanometric clusters and offer an effective approach for the generation of high-performance electrocatalysts for HER.

18.
RSC Adv ; 14(3): 2016-2026, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38196914

RESUMO

Due to persistent inflammation and limited osteogenesis, jawbone defects present a considerable challenge in regenerative medicine. Amelogenin, a major protein constituent of the developing enamel matrix, demonstrates promising capabilities in inducing regeneration of periodontal supporting tissues and exerting immunomodulatory effects. These properties render it a potential therapeutic agent for enhancing jawbone osteogenesis. Nevertheless, its clinical application is hindered by the limitations of monotherapy and its rapid release characteristics, which compromise its efficacy and delivery efficiency. In this context, calcium alginate hydrogel, recognized for its superior physicochemical properties and biocompatibility, emerges as a candidate for developing a synergistic bioengineered drug delivery system. This study describes the synthesis of an injectable calcium amelogenin/calcium alginate hydrogel using calcium alginate loaded with amelogenin. We comprehensively investigated its physical properties, its role in modulating the immunological environment conducive to bone healing, and its osteogenic efficacy in areas of jawbone defects. Our experimental findings indicate that this synthesized composite hydrogel possesses desirable mechanical properties such as injectability, biocompatibility, and biodegradability. Furthermore, it facilitates jawbone formation by regulating the bone-healing microenvironment and directly inducing osteogenesis. This research provides novel insights into the development of bone-tissue regeneration materials, potentially advancing their clinical application.

19.
Bioact Mater ; 37: 106-118, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39022616

RESUMO

Effective control of post-extraction hemorrhage and alveolar bone resorption is critical for successful extraction socket treatment, which remains an unmet clinical challenge. Herein, an injectable Tetra-PEG hydrogel that possesses rapid gelation, firm tissue adhesion, high mechanical strength, suitable degradability, and excellent biocompatibility is developed as a sutureless and coagulation-independent bioadhesive for the management of extraction sockets. Our results demonstrate that the rapid and robust adhesive sealing of the extraction socket by the Tetra-PEG hydrogel can provide reliable protection for the underlying wound and stabilize blood clots to facilitate tissue healing. In vivo experiments using an anticoagulated rat tooth extraction model show that the hydrogel significantly outperformed clinically used cotton and gelatin sponge in hemostatic efficacy, wound closure, alveolar ridge preservation, and in situ alveolar bone regeneration. Histomorphological evaluations reveal the mechanisms for accelerated bone repair through suppressed long-term inflammation, elevated collagen deposition, higher osteoblast activity, and enhanced angiogenesis. Together, our study highlights the clinical potential of the developed injectable Tetra-PEG hydrogel for treating anticoagulant-related post-extraction hemorrhage and improving socket healing.

20.
Purinergic Signal ; 9(4): 585-98, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23780311

RESUMO

Extracellular adenosine triphosphate (eATP) transduces purinergic signal and plays an important regulatory role in many biological processes, including tumor cell growth and cell death. A large amount of eATP exists in the fast-growing tumor center and inflammatory tumor microenvironment. Tumor cells could acquire anoikis resistance and anchorage independence in tumor microenvironment and further cause metastatic lesion. Whether such a high amount of eATP has any effect on the anchored and non-anchored tumor cells in tumor microenvironment has not been elucidated and is investigated in this study. Our data showed that autophagy helped hepatoma cells to maintain survival under the treatment of no more than 1 mM of eATP. Only when eATP concentration reached a relatively high level (2.5 mM), cell organelle could not be further maintained by autophagy, and apoptosis and cell death occurred. In hepatoma cells under treatment of 2.5 mM of eATP, an AMP-activated protein kinase (AMPK) pathway was dramatically activated while mTOR signaling pathway was suppressed in coordination with apoptosis. Further investigation showed that the AMPK/mTOR axis played a key role in tipping the balance between autophagy-mediated cell survival and apoptosis-induced cell death under the treatment of eATP. This work provides evidence to explain how hepatoma cells escape from eATP-induced cytotoxicity as well as offers an important clue to consider effective manipulation of cancer.


Assuntos
Trifosfato de Adenosina/administração & dosagem , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Adesão Celular/efeitos dos fármacos , Líquido Extracelular/metabolismo , Trifosfato de Adenosina/farmacocinética , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Microambiente Tumoral/efeitos dos fármacos
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