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1.
Int Dent J ; 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39127517

RESUMO

OBJECTIVES: Periodontitis is a prevalent oral disease that can significantly impact patients' life quality and systemic health. However, non-surgical subgingival scaling is largely compromised due to poor patient compliance, leading to a high recurrence rate of periodontitis. Therefore, this research aims to explore new approaches to enhance the effectiveness of existing local drug administration therapies. MATERIALS AND METHODS: Gelatin-oxidized dextran hydrogel loaded with calcium peroxide and penicillin (CP-P hydrogel) was synthesized and characterized using Universal mechanical testing machine, Fourier transform infrared spectroscopy, swelling test, and dissolved oxygen meter. Furthermore, the cytotoxicity, osteogenic ability, antibacterial behavior, and alveolar bone regenerating capability of CP-P hydrogel were conducted both in vitro and in vivo. RESULTS: The CP-P hydrogel demonstrated excellent mechanical properties, minimal swelling, and ideal biocompatibility. It created more favorable environments in the periodontal pocket by reversing anaerobic environment, eliminating drug-resistant bacteria and enhancing the therapeutic potency of drugs. By continuously releasing drugs in the periodontal pocket, the CP-P hydrogel effectively inhibited bacteria and reduce local inflammation response. In addition to bacteriostatic effects, the CP-P hydrogel also promoted the expression of osteogenic genes and enhanced osteogenic differentiation of PDLSCs in vitro. CONCLUSIONS: CP-P hydrogel can be developed as a new therapeutic platform to enhance the effectiveness of local drug administration strategy against periodontitis.

2.
Front Public Health ; 12: 1376540, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38765487

RESUMO

Background: The psychological status of Chinese postgraduate students majoring in stomatology after the COVID-19 restrictions still remains unclear. The objective of this study is to evaluate the mental status through a cross-sectional survey and gather related theoretical evidence for psychological intervention on postgraduate students majoring in stomatology. Methods: An online survey was administered, and subjective well-being, anxiety, stress and depression symptoms were assessed using the 5-item World Health Organization Well-Being Index (WHO-5), item Generalized Anxiety Disorder Scale (GAD-7), 10-item Perceived Stress Scale (PSS-10), and Patient Health Questionnaire-9 (PHQ-9), respectively, wherein suicidal ideation and sleep-related problems were measured with PHQ-9 and Insomnia Severity Index (ISI). Results: A total of 208 participants who completed one questionnaire were considered as valid. It was found that female respondents generally exhibited significantly higher levels of PSS-10, PHQ-9, and GAD-7 scores and shorter physical activity hours than male students. Students from rural areas demonstrated significantly higher levels of PHQ-9, suicidal ideation, and less portion of good or fair family economic support. Additionally, individuals from only-child families reported increased levels of activity hours (1.78 ± 2.07, p = 0.045) and a higher portion (55.10%, p = 0.007) of having clear future plan as compared with multiple-child families. The risk factors for anxiety symptoms (GAD-7 score) were higher scores of PSS-10 (OR = 1.15, 95% CI = 1.09-1.22), PHQ-9 (OR = 1.35, 95% CI = 1.22-1.49), and ISI-7 (OR = 1.14, 95% CI = 1.06-1.23), while owning a clear graduation plan was the protective factor (OR = 0.55, 95% CI = 0.31-0.98). Moreover, the risk factors for depressive symptoms (PHQ-9) included PSS-10 (OR = 1.10, 95% CI = 1.04-1.16), GAD-7 (OR = 1.38, 95% CI = 1.25-1.52), suicidal ideation (OR = 5.66, 95% CI = 3.37-9.51), and ISI-7 (OR = 1.17, 95% CI = 1.09-1.25). Approximately 98.08% of Chinese postgraduates studying stomatology reported experiencing at least moderate stress after the COVID-19 restrictions. Conclusion: Within the limitations of this study, senior students were more inclined to stress, while anxiety symptoms were related to severer levels of stress, depression, and insomnia. Depressive symptoms were associated with higher levels of stress, anxiety, insomnia, suicidal ideation, and lower levels of self-reported well-being. Thus, psychological interventions for postgraduates should be timely and appropriately implemented by strengthening well-being, reasonably planning for the future, and good physique, thereby mitigating the psychological issues after COVID-19 restrictions.


Assuntos
Ansiedade , COVID-19 , Depressão , Humanos , Masculino , Feminino , Estudos Transversais , COVID-19/epidemiologia , COVID-19/psicologia , China/epidemiologia , Adulto , Inquéritos e Questionários , Depressão/epidemiologia , Ansiedade/epidemiologia , Estresse Psicológico , Saúde Mental , Ideação Suicida , Adulto Jovem , SARS-CoV-2 , Estudantes/psicologia , População do Leste Asiático
3.
J Nanobiotechnology ; 22(1): 199, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654266

RESUMO

Considering the high recrudescence and the long-lasting unhealed large-sized wound that affect the aesthetics and cause dysfunction after resection of maxillofacial malignant skin tumors, a groundbreaking strategy is urgently needed. Photothermal therapy (PTT), which has become a complementary treatment of tumors, however, is powerless in tissue defect regeneration. Therefore, a novel multifunctional sodium nitroprusside and Fe2+ ions loaded microneedles (SNP-Fe@MNs) platform was fabricated by accomplishing desirable NIR-responsive photothermal effect while burst releasing nitric oxide (NO) after the ultraviolet radiation for the ablation of melanoma. Moreover, the steady releasing of NO in the long term by the platform can exert its angiogenic effects via upregulating multiple related pathways to promote tissue regeneration. Thus, the therapeutic dilemma caused by postoperative maxillofacial skin malignancies could be conquered through promoting tumor cell apoptosis via synergistic PTT-gas therapy and subsequent regeneration process in one step. The bio-application of SNP-Fe@MNs could be further popularized based on its ideal bioactivity and appealing features as a strategy for synergistic therapy of other tumors occurred in skin.


Assuntos
Melanoma , Óxido Nítrico , Terapia Fototérmica , Neoplasias Cutâneas , Animais , Terapia Fototérmica/métodos , Camundongos , Neoplasias Cutâneas/terapia , Melanoma/terapia , Óxido Nítrico/metabolismo , Óxido Nítrico/farmacologia , Linhagem Celular Tumoral , Agulhas , Humanos , Nitroprussiato/farmacologia , Apoptose/efeitos dos fármacos , Pele , Ferro/química , Raios Ultravioleta
4.
Int Dent J ; 74(1): 71-80, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37833209

RESUMO

OBJECTIVES: The aim of this research was to investigate the functions of Piezo channels in dentin defect, including mechanical signalling and odontoblast responses. METHODS: Rat dentin-defect models were constructed, and spatiotemporal expression of Piezo proteins was detected in the pulpo-dentinal complex. Real-time polymerase chain reaction (rtPCR) was used to investigate the functional expression pattern of Piezo channels in odontoblasts. Moreover, RNA interference technology was employed to uncover the underlying mechanisms of the Piezo-driven inflammatory response and repair under fluid shear stress (FSS) conditions in vitro. RESULTS: Piezo1 and Piezo2 were found to be widely expressed in the odontoblast layer and dental pulp in the rat dentin-defect model during the end stage of reparative dentin formation. The expression levels of the Piezo1 and Piezo2 genes in MDPC-23 cells were high in the initial stage under FSS loading and then decreased over time. Moreover, the expression trends of inflammatory, odontogenic, and mineralisation genes were generally contrary to those of Piezo1 and Piezo2 over time. After silencing of Piezo1/Piezo2, FSS stimulation resulted in significantly higher expression of inflammatory, odontogenesis, and mineralisation genes in MDPC-23 cells. Finally, the expression of genes involved in the integrin ß1/ERK1 and Wnt5b/ß-catenin signalling pathways was changed in response to RNA silencing of Piezo1 and Piezo2. CONCLUSIONS: Piezo1 and Piezo2 may be involved in regulating the expression of inflammatory and odontogenic genes in odontoblasts stimulated by FSS.


Assuntos
Odontoblastos , Ratos , Humanos , Animais , Odontoblastos/fisiologia
5.
Colloids Surf B Biointerfaces ; 234: 113691, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38070369

RESUMO

SEMA4D-modified titanium surfaces can indirectly regulate macrophages through endothelial cells to achieve an anti-inflammatory effect, which is beneficial for healing soft tissues around the gingival abutment. However, the mechanism of surface-induced cellular phenotypic changes in SEMA4D-modified titanium has not yet been elucidated. SEMA4D activates the RhoA signaling pathway in endothelial cells, which coordinates metabolism and cytoskeletal remodeling. This study hypothesized that endothelial cells inoculated on SEMA4D-modified titanium surfaces can direct M2 polarization of macrophages via metabolites. An indirect co-culture model of endothelial cells and macrophages was constructed in vitro, and specific inhibitors were employed. Subsequently, endothelial cell adhesion and migration, metabolic changes, Rho/ROCK1 expression, and inflammatory expression of macrophages were assessed via immunofluorescence microscopy, specific kits, qRT-PCR, and Western blotting. Moreover, an in vivo rat bilateral maxillary implant model was constructed to evaluate the soft tissue healing effect. The in vitro experiments showed that the SEMA4D group had stronger endothelial cell adhesion and migration, increased Rho/ROCK1 expression, and enhanced release of lactate. Additionally, decreased macrophage inflammatory expression was observed. In contrast, the inhibitor group partially suppressed lactate metabolism and motility, whereas increased inflammatory expression. The in vivo analyses indicated that the SEMA4D group had faster and better angiogenic and anti-inflammatory effects, especially in the early stage. In conclusion, via the Rho/ROCK1 signaling pathway, the SEMA4D-modified titanium surface promotes endothelial cell adhesion and migration and lactic acid release, then the paracrine lactic acid promotes the polarization of macrophages to M2, thus obtaining the dual effects of angiogenesis and anti-inflammation.


Assuntos
Antígenos CD , Células Endoteliais , Semaforinas , Titânio , Ratos , Animais , Titânio/farmacologia , Ácido Láctico , Macrófagos , Anti-Inflamatórios
6.
BMC Oral Health ; 23(1): 717, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37798684

RESUMO

BACKGROUND: The objective of this systematic review and meta-analysis was to evaluate the effects of non-surgical periodontal therapy (NSPT) on inflammatory-related cytokines/adipocytokines in periodontitis patients with or without obesity. METHODS: We followed the preferred reporting items for systematic reviews and meta-analyses statement and registered the study (CRD42022375331) in the Prospective International Register of Systematic Reviews. We screened randomized-controlled trials and controlled clinical trials from six databases up to December 2022. Quality assessment was performed with RoB-2 and ROBINS-I tools for randomized trials and non-randomized trials, respectively. Meta-analysis was carried out using a random-effect model. RESULTS: We included seventeen references in the systematic analysis, and sixteen in the meta-analysis. Baseline results of pro-inflammatory biomarkers, including serum interleukin (IL)-6, serum and gingival crevicular fluid (GCF), tumor necrosis factor (TNF)-a, serum C-reactive protein (CRP)/hs-CRP, and serum and GCF resistin, were higher in obesity subjects than in normal weight subjects. The effect of NSPT with respect to levels of cytokines/adipocytokines, including IL-6, TNF-a, CRP/hs-CRP, resistin, adiponectin, leptin and retinol binding protein 4 (RBP4), were then analyzed in the systematic and meta-analysis. After three months of NSPT, serum (MD = -0.54, CI = -0.62 - -0.46), and GCF (MD = -2.70, CI = -4.77 - -0.63) levels of IL-6, along with the serum RBP4 (MD = -0.39, CI = -0.68-0.10) decreased in periodontitis individuals with obesity. NSPT also improved GCF adiponectin levels after three months (MD = 2.37, CI = 0.29 - 4.45) in periodontitis individuals without obesity. CONCLUSIONS: Obese status altered the baseline levels of cytokines/adipocytokines (serum IL-6, serum and GCF TNF-a, serum CRP/hs-CRP, and serum and GCF resistin). Then NSPT can shift the levels of specific pro-inflammatory mediators and anti-inflammatory mediators in biological fluids, both in obesity and non-obesity individuals. NSPT can reduce serum and GCF IL-6 levels together with serum RBP4 level in individuals with obesity after 3 months, besides, there is no sufficient evidence to prove that obese patients have a statistically significant decrease in the levels of other cytokines compared to patients with normal weight. NSPT can also increase GCF adiponectin level in normal weight individuals after 3 months. Our findings imply the potential ideal follow-up intervals and sensitive biomarkers for clinical bioanalysis in personalized decision-making of effect of NSPT due to patients' BMI value.


Assuntos
Periodontite Crônica , Citocinas , Humanos , Citocinas/metabolismo , Adipocinas/análise , Adipocinas/metabolismo , Resistina , Proteína C-Reativa/metabolismo , Interleucina-6/metabolismo , Periodontite Crônica/terapia , Adiponectina , Estudos Prospectivos , Obesidade/complicações , Obesidade/terapia , Biomarcadores/análise , Fator de Necrose Tumoral alfa/metabolismo , Líquido do Sulco Gengival/química , Proteínas Plasmáticas de Ligação ao Retinol/metabolismo
7.
BMC Med Educ ; 22(1): 888, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36550519

RESUMO

OBJECTIVE: Mini clinical evaluation exercise (mini-CEX) and objective structured clinical examination (OSCE) are widely acknowledged as effective measures of resident standardization training (RST) in European and American countries. However, in China primary mini-CEX and OSCE forms are mainly limited in undergraduate clinical examination. Little knowledge is available regarding the validity and right way of mini-CEX /OSCE evaluation system in advanced dental clinical education so far. This study aimed to explore whether combination of mini-CEX and OSCE represents a global-dimension assessment for postgraduate clinical competence in RST. METHODS: Postgraduates who received RST from June 2017 to June 2019 were selected and evaluated by modified mini-CEX/OSCE scales. Each student received evaluations at least twice in the initial and final stages of training (tested every 4 months). A questionnaire was conducted to investigate the satisfaction with the arrangement of RST. RESULTS: Mini-CEX/OSCE test results indicated that postgraduates have significantly improved their comprehensive competence in RST projects in the department of prosthodontics (P < 0.05). Compared to other master of Stomatology students, postgraduates taking up prosthodontics master's degree have made more progresses through a training period of up to 1 year and four sessions of face-to-face feedback tutoring (P < 0.05). Survey results revealed high level of satisfaction on clinical practice evaluation. CONCLUSION: Modified mini-CEX/OSCE combined evaluation system is an effective and reliable assessment tool for clinical comprehensive ability in the RST of professional graduates and can fully highlight their respective advantages on the improvement of students' clinical competency, especially after several rounds of assessments.


Assuntos
Avaliação Educacional , Prostodontia , Humanos , Avaliação Educacional/métodos , Competência Clínica , Exame Físico , Estudantes
8.
Biomedicines ; 10(11)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36428473

RESUMO

Reactive oxygen species (ROS) are byproducts of cell metabolism produced by living cells and signal mediators in biological processes. As unstable and highly reactive oxygen-derived molecules, excessive ROS production and defective oxidant clearance, or both, are associated with the pathogenesis of several conditions. Among them, ROS are widely involved in oral and maxillofacial diseases, such as periodontitis, as well as other infectious diseases or chronic inflammation, temporomandibular joint disorders, oral mucosal lesions, trigeminal neuralgia, muscle fatigue, and oral cancer. The purpose of this paper is to outline how ROS contribute to the pathophysiology of oral and maxillofacial regions, with an emphasis on oral infectious diseases represented by periodontitis and mucosal diseases represented by oral ulcers and how to effectively utilize and eliminate ROS in these pathological processes, as well as to review recent research on the potential targets and interventions of cutting-edge antioxidant materials. The PubMed, Web of Science, and Embase databases were searched using the MesH terms "oral and maxillofacial diseases", "reactive oxygen species", and "antioxidant materials". Irrelevant, obsolete, imprecise, and repetitive articles were excluded through screening of titles, abstracts, and eventually full content. The full-text data of the selected articles are, therefore, summarized using selection criteria. While there are various emerging biomaterials used as drugs themselves or delivery systems, more attention was paid to antioxidant drugs with broad application prospects and rigorous prophase animal experimental results.

9.
Front Bioeng Biotechnol ; 10: 921284, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35957647

RESUMO

Bone tissues are dynamically reconstructed during the entire life cycle phase, which is an exquisitely regulated process controlled by intracellular and intercellular signals transmitted through physicochemical and biochemical stimulation. Recently, the role of electrical activity in promoting bone regeneration has attracted great attention, making the design, fabrication, and selection of bioelectric bio-reactive materials a focus. Under specific conditions, piezoelectric, photoelectric, magnetoelectric, acoustoelectric, and thermoelectric materials can generate bioelectric signals similar to those of natural tissues and stimulate osteogenesis-related signaling pathways to enhance the regeneration of bone defects, which can be used for designing novel smart biological materials for engineering tissue regeneration. However, literature summarizing studies relevant to bioelectric materials for bone regeneration is rare to our knowledge. Consequently, this review is mainly focused on the biological mechanism of electrical stimulation in the regeneration of bone defects, the current state and future prospects of piezoelectric materials, and other bioelectric active materials suitable for bone tissue engineering in recent studies, aiming to provide a theoretical basis for novel clinical treatment strategies for bone defects.

10.
Cancer Cell Int ; 21(1): 134, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33632229

RESUMO

BACKGROUND: Esophageal cancer is associated with high incidence and mortality worldwide. Differential expression genes (DEGs) and weighted gene co-expression network analysis (WGCNA) are important methods to screen the core genes as bioinformatics methods. METHODS: The DEGs and WGCNA were combined to screen the hub genes, and pathway enrichment analyses were performed on the hub module in the WGCNA. The CCNB1 was identified as the hub gene based on the intersection between DEGs and the greenyellow module in WGCNA. Expression levels and prognostic values of CCNB1 were verified in UALCAN, GEPIA2, HCMDB, Kaplan-Meier plotter, and TIMER databases. RESULTS: We identified 1,044 DEGs from dataset GSE20347, 1,904 from GSE29001, and 2,722 from GSE111044, and 32 modules were revealed by WGCNA. The greenyellow module was identified as the hub module in the WGCNA. CCNB1 gene was identified as the hub gene, which was upregulated in tumour tissues. Moreover, esophageal cancer patients with higher expression of CCNB1 showed a worse prognosis. However, CCNB1 'might not play an important role in immune cell infiltration. CONCLUSIONS: Based on DEGs and key modules related to esophageal cancer, CCNB1 was identified as the hub gene, which offered novel insights into the development and treatment of esophageal cancer.

11.
J Cardiovasc Electrophysiol ; 31(5): 1202-1210, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32162743

RESUMO

AIMS: His-Purkinje system pacing has been demonstrated as a synchronized ventricular pacing strategy via pacing His-Purkinje system directly, which can decrease the incidence of adverse cardiac structure alteration compared with right ventricular pacing (RVP). The purpose of this meta-analysis was to compare the effects of His-Purkinje system pacing and RVP in patients with bradycardia and cardiac conduction dysfunction. METHODS: PubMed, Embase, Cochrane Library, and Web of Science were systematically searched from the establishment of databases up to 15 December 2019. Studies on long-term clinical outcomes of His-Purkinje system pacing and RVP were included. Chronic paced QRS duration, chronic pacing threshold, left ventricular ejection fraction (LVEF), left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), all-cause mortality, and heart failure hospitalization were collected for meta-analysis. RESULTS: A total of 13 studies comprising 2348 patients were included in this meta-analysis. Compared with RVP group, patients receiving His-Purkinje system pacing showed improvement of LVEF (mean difference [MD], 5.65; 95% confidence interval [CI], 4.38-6.92), shorter chronic paced QRS duration (MD, - 39.29; 95% CI, - 41.90 to - 36.68), higher pacing threshold (MD, 0.8; 95% CI, 0.71-0.89) and lower risk of heart failure hospitalization (odds ratio [OR], 0.65; 95% CI, 0.44-0.96) during the follow-up. However, no statistical difference existed in LVEDV, LVESV and all-cause mortality between the two groups. CONCLUSION: Our meta-analysis suggests that His-bundle pacing is more suitable for the treatment of patients with bradycardia and cardiac conduction dysfunction.


Assuntos
Bradicardia/terapia , Fascículo Atrioventricular/fisiopatologia , Doença do Sistema de Condução Cardíaco/terapia , Estimulação Cardíaca Artificial , Frequência Cardíaca , Ramos Subendocárdicos/fisiopatologia , Potenciais de Ação , Idoso , Bradicardia/diagnóstico , Bradicardia/mortalidade , Bradicardia/fisiopatologia , Doença do Sistema de Condução Cardíaco/diagnóstico , Doença do Sistema de Condução Cardíaco/mortalidade , Doença do Sistema de Condução Cardíaco/fisiopatologia , Estimulação Cardíaca Artificial/efeitos adversos , Estimulação Cardíaca Artificial/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco , Fatores de Tempo , Função Ventricular Esquerda , Função Ventricular Direita
12.
J Bone Miner Res ; 34(6): 1169-1181, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30690778

RESUMO

Sirtuin 1 (Sirt1), a protein deacetylase, is a novel target for bone metabolism. To investigate whether overexpression of Sirt1 in mandibular mesenchymal stem cells (M-MSCs) increased alveolar bone mass in vivo, we generated Sirt1 transgenic mice (Sirt1TG ), with Sirt1 gene expression driven by the Prx1 gene, which represents the mesenchymal lineage. Our results demonstrated that overexpression of Sirt1 in M-MSCs increased the alveolar bone volume in 1-month-old, 9-month-old, and 18-month-old Sirt1TG mice compared with age-matched wild-type (WT) mice, and in ovariectomized Sirt1TG mice compared with ovariectomized WT mice by stimulating M-MSC differentiation into osteoblasts. Treatment with resveratrol, a Sirt1 activator, increased Sirt1 binding with Bmi1 and reduced Bmi1 acetylation in a dose-dependent manner demonstrated in M-MSC cultures. Both treatment with resveratrol in M-MSC cultures and overexpressed Sirt1 in M-MSCs ex vivo cultures increased nuclear translocation of Bmi1. Furthermore, we demonstrated that deletion of Bmi1 blocked the increased alveolar bone volume in Sirt1TG mice. The Sirt1 activator resveratrol inhibited human MSC senescence and promoted their differentiation into osteoblasts, which were associated with upregulating the expression levels of Sirt1 and nuclear translocation of Bmi1. The present results suggested that Sirt1 promotes MSC proliferation and osteogenic differentiation, inhibits MSC senescence to increase alveolar bone volume by promoting the deacetylation and nuclear translocation of Bmi1. Thus, our study elucidated the mechanism by which Sirt1 increases alveolar bone mass, and these findings are important for the clinical application of the Sirt1 activator resveratrol for the promotion of alveolar bone formation and prevention of alveolar bone loss. © 2019 American Society for Bone and Mineral Research.


Assuntos
Processo Alveolar/metabolismo , Processo Alveolar/patologia , Diferenciação Celular , Osteogênese , Complexo Repressor Polycomb 1/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Sirtuína 1/metabolismo , Acetilação , Adolescente , Adulto , Idoso , Animais , Núcleo Celular/metabolismo , Proliferação de Células , Senescência Celular , Feminino , Humanos , Células-Tronco Mesenquimais/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pessoa de Meia-Idade , Tamanho do Órgão , Ovariectomia , Transporte Proteico , Adulto Jovem
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