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1.
Opt Express ; 31(16): 26301-26313, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710493

RESUMO

We have developed a simple time-bin phase encoding quantum key distribution system, using the optical injection locking technique. This setup incorporates both the merits of simplicity and stability in encoding, and immunity to channel disturbance. We have demonstrated the field implementation of quantum key distribution over long-distance deployed aerial fiber automatically. During the 70-day field test, we achieved approximately a 1.0 kbps secure key rate with stable performance. Our work takes an important step toward widespread implementation of QKD systems in diverse and complex real-life scenarios.

2.
Neurol Sci ; 43(9): 5523-5531, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35606674

RESUMO

OBJECTIVES: The growth and development of tumors are closely related to the initiation and amplification of the inflammatory response. Various inflammatory biomarkers had attained growing attention for nearly two decades and were discovered strongly associated with cancer patients' prognosis, indicating that systemic inflammatory response is possibly essential to cancer progression. However, little was known about the sensitive biomarkers associated with the detection, persistence, treatment, and prognosis of GBM. Hence, the retrospective research endeavored to evaluate the prognostic value of preoperative inflammatory biomarkers in patients with GBM who initially received standardized treatment. METHODS: The 232 glioblastoma patients eligible who were admitted to Qilu Hospitals in Shandong Province from January 2014 to January 2018 were collected for this analysis. Inflammatory markers, including the systemic immune-inflammation index (SII), systemic immune response index (SIRI), neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), monocyte-lymphocyte ratio (MLR), and albumin/globulin ratio (AGR), were designed. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method, and we calculated the area under the ROC curve to determine the AUC value. Besides, we used the Cox proportional hazard model to estimate the relationship between variables and PFS and OS. The statistical differences between variables and PFS and OS were tested through the log-rank test. What is more, the LR method was used to perform Cox multiple regression analysis. The results were represented by hazard ratio (HR), 95% CI, any 2-tailed P < 0.01 was accepted as statistically different. RESULTS: The multivariate Cox proportional hazard model presented that SII ≥ 659.1 was an independent risk factor affecting OS (HR = 2.238, 95% CI = 1.471-3.406, P < 0.001) and postoperative PFS (HR = 2.000, 95% CI = 1.472-2.716, P < 0.001) in GBM patients. The 1-, 3-, and 5-year OS of the SII < 659.1 group was 70.8%, 26.9%, and 14.1%, respectively, while the 1- and 3-year OS of the SII ≥ 659.1 group was 37.5% and 11.5% (P < 0.001). The 1-, 3-, and 5-year PFS of the SII < 659.1 group was 36.3%, 19.6%, and 13%, respectively, while the 1-year PFS of the SII ≥ 659.1 group was 11.3% (P < 0.001). Results of patients' clinical and pathological characteristics paraded that in comparison to the lower SII group, the higher SII group had significantly inferior Karnofsky Performance Scale (KPS) scores (P < 0.001) and more frequent cystic changes of the tumors (P < 0.001), whereas the values of SIRI, NLR, PLR, MLR, and AGR were low. CONCLUSIONS: SII is an independent inflammatory indicator for predicting the prognosis of GBM patients after receiving initially standardized treatments.


Assuntos
Glioblastoma , Glioblastoma/patologia , Glioblastoma/cirurgia , Humanos , Inflamação , Linfócitos/patologia , Neutrófilos/patologia , Prognóstico , Estudos Retrospectivos
3.
BMC Oral Health ; 22(1): 391, 2022 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-36088323

RESUMO

BACKGROUND: When evaluating the efficacy and safety of various desensitizing products in vitro, their mechanism of action and clinical utility should be considered during test model selection. This study aimed to evaluate the effects of two desensitizers, an in-office use material and an at-home use material, on dentin specimen permeability, and their dentin barrier cytotoxicity with appropriate test models. METHODS: Two materials, GLUMA desensitizer (GLU) containing glutaraldehyde and remineralizing and desensitizing gel (RD) containing sodium fluoride and fumed silica, were selected. Human dentin specimens were divided into three groups (n = 6): in groups 1 and 2, GLU was applied, and in group 3, RD was applied and immersed in artificial saliva (AS) for 24 h. Dentin specimen permeability before and after each treatment/post-treatment was measured using a hydraulic device under a pressure of 20 cm H2O. The perfusion fluid was deionized water, except in group 2 where 2% bovine serum albumin (BSA) was used. The representative specimens before and after treatment from each group were investigated using scanning electron microscopy. To measure cytotoxicity, test materials were applied to the occlusal surfaces of human dentin disks under which three-dimensional cell scaffolds were placed. After 24-h contact within the test device, cell viability was measured via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. RESULTS: GLU significantly reduced the dentin permeability and occluded the dentinal tubules when 2% BSA was used as perfusion fluid. RD significantly reduced dentin permeability and occluded the tubules, but permeability rebounded after AS immersion. GLU significantly decreased cell viability, but RD was non-cytotoxic. CONCLUSIONS: In vitro GLU application induced effective dentinal tubule occlusion only following the introduction of simulated dentinal fluid. RD provided effective tubule occlusion, but its full remineralization potential was not realized after a short period of immersion in AS. GLU may harm the pulp, whereas RD is sufficiently biocompatible.


Assuntos
Dessensibilizantes Dentinários , Sensibilidade da Dentina , Dentina , Dessensibilizantes Dentinários/farmacologia , Dessensibilizantes Dentinários/uso terapêutico , Permeabilidade da Dentina , Sensibilidade da Dentina/tratamento farmacológico , Humanos , Teste de Materiais
4.
Clin Oral Investig ; 23(2): 899-904, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29948279

RESUMO

OBJECTIVES: To investigate the effects of two disinfection/sterilization methods on the permeability of dentin specimens. MATERIALS AND METHODS: Forty intact human third molars were freshly extracted and cut, close to the pulp chamber, into dentin disks with a 500-µm thickness. The disks were randomized (n = 20 each) into a 70% ethanol group (acid-etched dentin disks soaked in 70% ethanol for 15 min) and a steam autoclaving group (acid-etched dentin disks autoclaved for 25 min). The permeability (Lp) of each dentin disk was measured before and after either treatment using a hydraulic device, and intra- and inter-group differences in values before and after treatment were analyzed using t tests. Field emission scanning electron microscopy (FE-SEM) micrographs of the dentin surface were acquired and examined. FE-SEM samples were prepared using the critical point drying (CPD) method. RESULTS: Immersion in 70% ethanol increased the Lp values of dentin specimens by 17%, which was not statistically significant. Steam autoclaving significantly reduced dentin permeability by 66% because the dentin collagen mesh became compact and collapsed, as detected by FE-SEM. CONCLUSIONS: The disinfection of acid-etched dentin disks using 70% ethanol for 15 min does not significantly affect dentin permeability, whereas sterilization of acid-etched dentin disks via autoclaving significantly reduces dentin permeability. CLINICAL RELEVANCE: Considering the influences of dentin permeability by disinfection/sterilization methods, the disinfection of the acid-etched dentin disks using 70% ethanol for 15 min could be used for the study related to dentin permeability, while the sterilization of autoclaving could not.


Assuntos
Permeabilidade da Dentina , Desinfecção/métodos , Etanol/farmacologia , Condicionamento Ácido do Dente , Permeabilidade da Dentina/efeitos dos fármacos , Temperatura Alta , Humanos , Técnicas In Vitro , Teste de Materiais , Microscopia Eletrônica de Varredura , Dente Serotino , Propriedades de Superfície
5.
J Relig Health ; 58(2): 490-505, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30879208

RESUMO

This study examines factors contributing to depression among migrant factory workers in Shanghai. A survey was designed with mental health questions under a framework explaining: (1) social capital, (2) migratory stress, and (3) mental health consequences. With a return rate of 98.3%, 1966 individuals completed the survey. Only 11.1% of the respondents indicated having a religious affiliation. The findings are not surprising about the relationship between trust, economic condition, and depression. However, it is surprising to find that not having a religious affiliation is significantly connected to better mental health. The effect of religious beliefs should be examined as a trust factor to remove the barrier of perceiving religion as an added stressor.


Assuntos
Depressão , Transtorno Depressivo , Religião , China , Feminino , Humanos , Masculino , Saúde Mental , Migrantes/psicologia , Local de Trabalho
6.
J Prosthet Dent ; 120(2): 319.e1-319.e6, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30097265

RESUMO

STATEMENT OF PROBLEM: Components fabricated by selective laser melting (SLM) deform because of residual stress, but heat treatment allows the release of that stress and avoids deformation. Although dental cobalt-chromium (Co-Cr) alloy has been specifically designed for SLM, the effects of heat treatment on the metal-ceramic combination of SLM Co-Cr restorations require investigation. PURPOSE: The purpose of this in vitro study was to evaluate the effects of heat treatment on the metal-ceramic combination of SLM Co-Cr alloy. MATERIAL AND METHODS: Following ISO 9693:2012, Co-Cr metal strips (Solibond C Plus cast alloy and SLM powders; YETI Dental) were fabricated with a dimension of 25×3×0.5 mm by casting and SLM. The SLM specimens were divided into 3 subgroups (n=15 for each subgroup). Two subgroups were subjected to heat treatment at 880°C (SLM-880) and 1100°C (SLM-1100). The third subgroup was not subjected to heat treatment and served as a control (As-SLM). Cast specimens (n=15) also acted as a control. A porcelain layer with a thickness of 1.1 mm was fired to the central area (3×8 mm) of each specimen. The 3-point bend test was used to evaluate the metal-ceramic bond strength (τb). The fractured metal surfaces were examined by the naked eye, using a digital camera, and also using a scanning electron microscope. The area fraction of adherence porcelain (AFAP) was determined by measuring the atomic percentage of silicon using energy-dispersive x-ray spectroscopy (EDS). One-way ANOVA and the Kruskal-Wallis test, followed by the Mann-Whitney test (α=.05), were used for statistical analysis. RESULTS: The 1-way ANOVA found no significant difference in the bond strength among the 4 groups. The EDS analysis indicated that specimens in the groups receiving heat treatment (SLM-880 and SLM-1100) showed higher AFAP values than those in the As-SLM group (P<.05). The SLM-880 also showed significantly higher AFAP values than the SLM-1100. Compared with the cast group, significant differences in AFAP values were also observed, and the specimens in the order of highest to lowest AFAP values were SLM-880>cast>As-SLM; no significant difference was found between the SLM-1100 and cast groups. CONCLUSIONS: Heat treatment at 880°C and 1100°C did not affect the metal-ceramic bond strength of Co-Cr alloy made by SLM but did improve the porcelain adherence. SLM-fabricated and heat-treated Co-Cr alloy shows comparable or more porcelain adherence than cast specimens.


Assuntos
Cerâmica/química , Ligas de Cromo/química , Cobalto/química , Temperatura Alta/efeitos adversos , Lasers/efeitos adversos , Ligas Metalo-Cerâmicas/química , Análise de Variância , Colagem Dentária , Técnica de Fundição Odontológica , Porcelana Dentária/química , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Espectrometria por Raios X , Estresse Mecânico , Propriedades de Superfície , Resistência à Tração
7.
ScientificWorldJournal ; 2014: 265816, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25177717

RESUMO

Deep-sea permanent magnet motor equipped with fluid compensated pressure-tolerant system is compressed by the high pressure fluid both outside and inside. The induced stress distribution in stator core is significantly different from that in land type motor. Its effect on the magnetic properties of stator core is important for deep-sea motor designers but seldom reported. In this paper, the stress distribution in stator core, regarding the seawater compressive stress, is calculated by 2D finite element method (FEM). The effect of compressive stress on magnetic properties of electrical steel sheet, that is, permeability, BH curves, and BW curves, is also measured. Then, based on the measured magnetic properties and calculated stress distribution, the stator iron loss is estimated by stress-electromagnetics-coupling FEM. At last the estimation is verified by experiment. Both the calculated and measured results show that stator iron loss increases obviously with the seawater compressive stress.


Assuntos
Força Compressiva , Equipamentos e Provisões Elétricas , Ferro/química , Campos Magnéticos , Água do Mar/efeitos adversos , Aço/química
8.
Adv Mater ; 36(8): e2310164, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37925614

RESUMO

Hydrogel adhesion materials are widely reported for tissue engineering repair applications, however, wet tissue surface moisture can reduce the wet-adhesion properties and mechanical strength of hydrogels limiting their application. Here, anti-hydration gelatin-acrylic acid-ethylene dimethacrylate (GAE) hydrogels with hydrophobic cross-linked chains are constructed. The prepared GAE hydrogel is soaked in PBS (3 days) with a volume change of 0.6 times of the original and the adhesive strength, Young's modulus, toughness, and burst pressure are maintained by ≈70% of the original. A simple and universal method is used to introduce hydrophobic chains as cross-linking points to prepare hydrogels with anti-hydration, toughness, and high wet state adhesion. The hydrophobic cross-linked chains not only restrict the movement of molecular chains but also hinder the intrusion of water molecules. Antihydration GAE hydrogels exhibit good biocompatibility, slow drug release, and dynamic oral wet-state tissue repair properties. Therefore, the anti-hydration hydrogel has excellent toughness, wet tissue adhesion properties, and good prospects for biological applications.


Assuntos
Hidrogéis , Engenharia Tecidual , Humanos , Hidrogéis/química , Aderências Teciduais , Resistência à Tração , Interações Hidrofóbicas e Hidrofílicas , Adesivos
9.
Carbohydr Polym ; 346: 122648, 2024 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-39245508

RESUMO

Uncontrolled non-compressible hemorrhage, which is often accompanied by coagulopathy, is a major cause of mortality following traumatic injuries in civilian and military populations. In this study, coagulopathy-independent injectable catechol-modified chitosan (CS-HCA) hemostatic materials featuring rapid shape recovery were fabricated by combining controlled sodium tripolyphosphate-crosslinking with hydrocaffeic acid (HCA) grafting. CS-HCA exhibited robust mechanical strength and rapid blood-triggered shape recovery. Furthermore, CS-HCA demonstrated superior blood-clotting ability, enhanced blood cell adhesion and activation, and greater protein adsorption than commercial hemostatic gauze and Celox. CS-HCA showed enhanced procoagulant and hemostatic capacities in a lethal liver-perforation wound model in rabbits, particularly in heparinized rabbits. CS-HCA is suitable for mass manufacturing and shows promise as a clinically translatable hemostat.


Assuntos
Catecóis , Quitosana , Hemorragia , Hemostáticos , Quitosana/química , Quitosana/farmacologia , Animais , Coelhos , Catecóis/química , Catecóis/farmacologia , Hemorragia/tratamento farmacológico , Hemostáticos/química , Hemostáticos/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Ácidos Cafeicos/química , Ácidos Cafeicos/farmacologia , Masculino , Materiais Inteligentes/química , Injeções
10.
J Dent Sci ; 18(3): 1016-1022, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37404657

RESUMO

Background/purpose: Few studies have focused on the influence of simulated toothbrush abrasion on the surface qualities of novel nanofilled and nanohybrid composites. The aim of the study was to evaluate the surface roughness and gloss values of resin-based composite (RBC) materials with various filler types before and after simulated toothbrush abrasion. Materials and methods: One nanofilled (Filtek Z350 XT [FT3]), two nanohybrids (Harmonize [HM] and Clearfil Majesty [CM]) and one microhybrid (Filtek Z250 [FT2]) were evaluated. Twelve specimens of each material were made and polished with silicon carbide sandpapers. Initial surface roughness and gloss values were measured as negative controls. Then, all specimens were subjected to simulated toothbrush abrasion on a custom-made apparatus. After 2000, 4000 and 8000 cycles, the surface roughness and gloss values of all specimens were tested. One additional specimen from each group was selected for scanning electron microscope (SEM) analysis. Results: For FT3, Ra and GU values did not significantly change until after 8000 cycles during the process of toothbrushing (P > 0.05). For HM, CM and FT2, the Ra and GU values significantly decreased after 4000 and 8000 cycles of toothbrush abrasion (P < 0.05). After 8000 cycles of toothbrush abrasion, FT3 presented the lowest surface roughness and highest gloss values of all materials (P < 0.05). SEM images showed that surface textures and irregularities corresponded to the results of surface roughness and gloss. Conclusion: Surface roughness and gloss after simulated toothbrush abrasion were material dependent. Nanofilled resin composite presented the lowest Ra values and highest GU values.

11.
Oncol Lett ; 25(5): 205, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37123022

RESUMO

The objective of the present study was to investigate the role of postoperative radiotherapy (PORT) after radical resection of stage IIIA-N2 non-small cell lung cancer (NSCLC). Subgroups of patients who benefited from PORT were evaluated. A retrospective review of 288 consecutive patients with resected pIIIA-N2 NSCLC at Beijing Chest Hospital (Beijing, China) was performed. Of these patients, 61 received PORT. The 288 patients were divided into PORT and non-PORT groups according to the treatment received. The baseline characteristics of the two patient groups were balanced using propensity score-matching (PSM; 1:1 matching). In total, 60 patients in the PORT group and 60 patients in the non-PORT group were matched. After PSM, the median survival time of the matched patients was 53 months. The 1-, 3- and 5-year overall survival (OS) rates of the PORT patient group were 95.0, 63.2 and 48.2%, respectively, while those of the non-PORT group were 86.7, 58.3 and 34.5%, respectively, and there was no significant difference between the two groups (P=0.056). The 5-year local recurrence-free survival (LRFS) rate in the PORT group was significantly improved (P=0.001). The effects of PORT on OS and LRFS rates were analysed in patients with different clinicopathological features. For subgroups with multiple N2 stations, N2 positive lymph nodes ≥4 and squamous cell carcinoma, PORT significantly increased the OS and LRFS rates (P<0.05). In conclusion, there was no statistically significant improvement in the 5-year OS rate with PORT overall, but there may be subgroups, such as patients with multiple N2 stations, N2 positive nodes ≥4 and squamous cell carcinoma histology, that could be explored as potentially benefitting from improved 5-year OS and LRFS rates with PORT.

12.
Ann Transl Med ; 11(9): 313, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37404984

RESUMO

Background: Composite scaffolds that maximize the advantages of different polymers are widely utilized in guided tissue regeneration (GTR). Some studies found that novel composite scaffolds composed of electrospun polycaprolactone/fluorapatite (ePCL/FA) actively promoted the osteogenic mineralization of various cell types in vitro. However, only a few studies have addressed the application of this composite scaffold membrane material in vivo. In this study, the ability of ePCL/FA composite scaffolds in vivo and their possible mechanisms were preliminarily explored. Methods: In this study, ePCL/FA composite scaffolds were characterized and their effects on bone tissue engineering and repair of calvarial defects in rats were examined. Sixteen male Sprague-Dawley (SD) rats were randomly categorized into four groups: normal group (integral cranial structure without defect), control group (cranial defect), ePCL group (cranial defect repaired by electrospun polycaprolactone scaffolds), and ePCL/FA group (cranial defect repaired by fluorapatite-modified electrospun polycaprolactone scaffolds). At 1 week, 2 months, and 4 months, micro-computed tomography (micro-CT) analysis was performed to compare the bone mineral density (BMD), bone volume (BV), tissue volume (TV), and bone volume percentage (BV/TV). The effects of bone tissue engineering and repair were observed by histological examination (hematoxylin and eosin, Van Gieson, and Masson respectively) at 4 months. Results: In water contact angle measurement, the average contact angle for the ePCL/FA group was significantly lower than that for the ePCL group, indicating that the FA crystal improved the hydrophilicity of the copolymer. Micro-CT analysis revealed that the cranial defect had no significant change at 1 week; however, the BMD, BV, and BV/TV of the ePCL/FA group were significantly higher than those of the control group at 2 and 4 months. Histological examination showed that the cranial defects were almost completely repaired by the ePCL/FA composite scaffolds at 4 months compared to the control and ePCL groups. Conclusions: The introduction of a biocompatible FA crystal improved the physical and biological properties of the ePCL/FA composite scaffolds; thus, these scaffolds demonstrate outstanding osteogenic potential for bone and orthopedic regenerative applications.

13.
Front Oncol ; 13: 1238051, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023152

RESUMO

CD147 also known as EMMPRIN, basigin, and HAb18G, is a single-chain type I transmembrane protein shown to be overexpressed in aggressive human cancers of CNS, head and neck, breasts, lungs, gastrointestinal, genitourinary, skin, hematological, and musculoskeletal. In these malignancies, the molecule is integral to the diverse but complimentary hallmarks of cancer: it is pivotal in cancerous proliferative signaling, growth propagation, cellular survival, replicative immortality, angiogenesis, metabolic reprogramming, immune evasion, invasion, and metastasis. CD147 also has regulatory functions in cancer-enabling characteristics such as DNA damage response (DDR) and immune evasion. These neoplastic functions of CD147 are executed through numerous and sometimes overlapping molecular pathways: it transduces signals from upstream molecules or ligands such as cyclophilin A (CyPA), CD98, and S100A9; activates a repertoire of downstream molecules and pathways including matrix metalloproteinases (MMPs)-2,3,9, hypoxia-inducible factors (HIF)-1/2α, PI3K/Akt/mTOR/HIF-1α, and ATM/ATR/p53; and also functions as an indispensable chaperone or regulator to monocarboxylate, fatty acid, and amino acid transporters. Interestingly, induced loss of functions to CD147 prevents and reverses the acquired hallmarks of cancer in neoplastic diseases. Silencing of Cd147 also alleviates known resistance to chemoradiotherapy exhibited by malignant tumors like carcinomas of the breast, lung, pancreas, liver, gastric, colon, ovary, cervix, prostate, urinary bladder, glioblastoma, and melanoma. Targeting CD147 antigen in chimeric and induced-chimeric antigen T cell or antibody therapies is also shown to be safer and more effective. Moreover, incorporating anti-CD147 monoclonal antibodies in chemoradiotherapy, oncolytic viral therapy, and oncolytic virus-based-gene therapies increases effectiveness and reduces on and off-target toxicity. This study advocates the expedition and expansion by further exploiting the evidence acquired from the experimental studies that modulate CD147 functions in hallmarks of cancer and cancer-enabling features and strive to translate them into clinical practice to alleviate the emergency and propagation of cancer, as well as the associated clinical and social consequences.

14.
Beijing Da Xue Xue Bao Yi Xue Ban ; 44(2): 303-6, 2012 Apr 18.
Artigo em Chinês | MEDLINE | ID: mdl-22517009

RESUMO

OBJECTIVE: This study was designed to investigate the properties of self-adhering flowable composite by comparison with self-etching adhesive and traditional composite. Moreover, the effect of additional etching process on the bond strength of dentin was investigated. METHODS: Totally 90 bovine incisors were prepared to expose the dentin, and then divided into three groups (Group A, Group B and Group C). A, B and C were treated with flowable composite, flowable composite and self-etching adhesive, traditional composite and self-etching adhesive respectively. These groups were further divided into two subgroups, without additional etching process(i.e. A1, B1 and C1) and with additional etching process (i.e. A2, B2 and C2). The bond strength of those samples was measured and the results were analyzed with a one-way ANOVA. RESULTS: The shear bond strength of A1 [(3.39±1.71 ) MPa] was lower than B1 [(21.58±4.50) MPa],and there is significant difference (P<0.05) between them. There is no significant difference (P>0.05) between B1 and C1 [(19.31±6.79) MPa]. After additional etching process, the shear bond strength of A2 [(6.75±3.54) MPa] was higher than A1. As for self-etching adhesive, the shear bond strength of B2 [(16.56±7.39) MPa] was lower than B1 (P<0.05) and C2 [(11.31±5.54) MPa] was lower than C1 (P<0.05). CONCLUSION: The bond strength of self-adhering flowable composite was lower than that of flowable composite with self-etching adhesive. There was no significant difference between bond strength of flowable composite with self-etching adhesive and traditional composite with self-etching adhesive. However, the additional etching process would decrease bond strength of self-etching adhesive and increase the coefficient of variation of measured results.


Assuntos
Resinas Compostas/química , Colagem Dentária , Cimentos Dentários/química , Condicionamento Ácido do Dente , Animais , Bovinos , Restauração Dentária Permanente/classificação , Restauração Dentária Permanente/métodos , Análise do Estresse Dentário , Adesivos Dentinários/química , Incisivo , Resistência ao Cisalhamento
15.
Beijing Da Xue Xue Bao Yi Xue Ban ; 44(6): 946-9, 2012 Dec 18.
Artigo em Chinês | MEDLINE | ID: mdl-23247464

RESUMO

OBJECTIVE: To study the change in properties of heat-polymerized acrylic resin after using one denture cleanser. METHODS: In the study, 20 disk-shaped (50.0 mm×0.5 mm) and 40 rectangular (34.0 mm×13.5 mm×1.3 mm) specimens prepared from heat-polymerized acrylic resin were randomly divided into four groups. The specimens were exposed to one of the three treatments as follows: Group 1 was without any treatment, Group 2 was exposed to air, Group 3 to distilled water, and Group 4 to Polident. The 4 exposures lasting 8 hours were conducted daily and repeated for 30 days. The color stability of heat-polymerized acrylic resin was determined by visual methods. The flexural strength and bonding strength of acrylic resin were measured using a universal testing machine. All the results were analyzed using ANOVA. RESULTS: The flexural strength test of acrylic resin demonstrated significant differences between Group 4 and Group 1 (P<0.05), there were no significant differences among Group 1, Group 2 and Group 3. No significant differences were found in other properties of the test materials. CONCLUSION: Long-term use of polident could alter the physical and mechnical properties of heat-polymerized acrylic resin. It may be related to the accelerating aging of resins caused by certain chemicals in denture cleansers. Polident may have some adverse effects on denture materials for decreasing flexural strength of heat-polymerized acrylic resin after 30-day immersion.


Assuntos
Resinas Acrílicas/química , Boratos/efeitos adversos , Materiais Dentários/química , Higienizadores de Dentadura/efeitos adversos , Sulfatos/efeitos adversos , Boratos/farmacologia , Higienizadores de Dentadura/farmacologia , Polímeros , Estresse Mecânico , Sulfatos/farmacologia
16.
J Dent Sci ; 17(3): 1212-1216, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35784133

RESUMO

Background/purpose: Bulk-fill resin-based composites (RBCs) are a new class of restorative materials, and polymerization shrinkage (PS) is concerned due to their single increment up to 4 mm. The aim of this study was to evaluate the PS and shrinkage stress (SS) of bulk-fill RBCs in vitro. Materials and methods: Three bulk-fill RBCs and three conventional non-bulk-fill RBCs were selected. The PS was determined with Acuvol volumetric shrinkage analyzer by calculating the specimen volume variation before and after light irradiation. The SS was investigated using universal testing machine method with a polymethyl methacrylate rod as a bonding substrate. The force generated during the polymerization process was detected by a load cell linked to a computer. SS was calculated by dividing the maximum stress force by the area of the rod. Results: The mean PS of various RBCs ranged from 1.72% to 2.13%. All PS results of bulk-fill RBCs were comparable to their conventional counterparts. Sonicfill 2 (SF2) and Harmonize (HM) showed the lowest PS (p < 0.05; Tukey HSD test). Medians of SS results ranged from 0.55 MPa to 0.67 MPa. All SSs of bulk-fill RBCs were comparable to their conventional counterparts. SF2 showed significantly lower SS than Tetric N-Ceram (TN) and Tetric N-Ceram Bulk Fill (TNB) (p < 0.0083; post hoc comparisons with Bonferroni adjustments). A moderate, positive correlation was observed between PS and SS with Pearson's correlation (r = 0.446, p = 0.013). Conclusion: Both PS and SS are material dependent. A moderate, positive correlation between PS and SS is found with new bulk-fill RBCs and their conventional counterparts.

17.
J AOAC Int ; 105(4): 1183-1192, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34623419

RESUMO

BACKGROUND: Secoisolariciresinol diglucoside (SDG) is a natural antioxidant generally extracted from flaxseed, which is one of the most important oil crops in China, the by-product of the flaxseed oil, i.e., flaxseed meal still contains a lot of lignans. However, flaxseed meal is generally treated as waste, resulting in a huge waste of resources. OBJECTIVE: To establish an efficient and convenient method for extraction and purification of lignans from flaxseed meal. METHODS: First, we used response surface methodology (RSM) to optimize the extraction conditions of the ultrasonic-assisted (UA) aqueous two-phase system (ATPS), and we obtained the purified extracts by macroporous resin purification (MRP). Second, the antioxidant ability of the extracts was studied in vitro. RESULTS: The best extraction conditions obtained were as follows: 9.0% (w/w) sodium hydroxide; 30.0% (w/w) isopropanol; extraction time, 39 min; liquid-to-solid ratio, 52.0 mL/g; ultrasonic wave, 560 W; and extraction temperature, 40°C. Under the optimal conditions, the purity of crude extracts (SDG-APTS-C) reached 21.5%. The desorption conditions of MRP were as follows: eluting 3 BV with ultrapure water, and then eluting with 25% ethanol at 2 BV (bed volume)/h to collect eluents. The purified extracts (SDG-ATPS-P) had a purity quotient of 73.9%, which was 52.4% higher than that of SDG-ATPS-C. Additionally, experiments conducted revealed that SDG-ATPS-C and SDG-ATPS-P could effectively remove DPPH (2,2-Diphenyl-1-picrylhydrazyl), ABTS (2,-Azinobis-3-ethylbenzthiazoline-6-sulphonate), and hydroxyl free radicals in vitro. CONCLUSIONS: The method was validated for extracting SDG from flaxseed meal, thus achieving the reuse of flaxseed meal. HIGHLIGHTS: This research provides some references for the application of UAATPS combined with MRP in natural products.


Assuntos
Linho , Lignanas , Antioxidantes , Ultrassom , Água
18.
Acta Biomater ; 149: 126-138, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35840105

RESUMO

There are many problems and challenges related to the treatment of highly prevalent oral mucosal diseases and oral drug delivery because of a large amount of saliva present in the oral cavity, the accompanying oral movements, and unconscious swallowing in the mouth. Therefore, an ideal oral dressing should possess stable adhesion and superior tough strength in the oral cavity. However, this fundamental requirement greatly limits the use of synthetic adhesive dressings for oral dressings. Here, we developed a mussel-inspired Janus gelatin-polydopamine-nano-clay (GPC) hydrogel with controlled adhesion and toughness through the synergistic physical and chemical interaction of gelatin (Gel), nano-clay, and dopamine (DA). The hydrogel not only exhibits strong wet adhesion force (63 kPa) but also has high toughness (1026 ± 100 J m-3). Interfacial adhesion of hydrogels is achieved by modulating the interaction of catechol groups of the hydrogel with specific functional groups (e.g., NH2, SH, OH, and COOH) on the tissue surface. The matrix dissipation of the hydrogel is regulated by physical crosslinking of gelatin, chemical crosslinking of gelatin with polydopamine (Michael addition and Schiff base formation), and nano-clay-induced constraint of the molecular chain. In addition, the GPC hydrogel shows high cell affinity and favors cell adhesion and proliferation. The hydrogel's instant and strong mucoadhesive properties provide a long-lasting therapeutic effect of the drug, thereby enhancing the healing of oral ulcers. Therefore, mussel-inspired wet-adhesion Janus GPC hydrogels can be used as a platform for mucosal dressing and drug delivery systems. STATEMENT OF SIGNIFICANCE: It is a great challenge to treat oral mucosal diseases due to the large amount of saliva present in the oral cavity, the accompanying oral movements, unconscious swallowing, and flushing of drugs in the mouth. To overcome the significant limitations of clinical bioadhesives, such as weakness, toxicity, and poor usage, in the present study, we developed a simple method through the synergistic effects of gelatin, polydopamine, and nano-clay to prepare an optimal mucosal dressing (Janus GPC) that integrates Janus, adhesion, toughness, and drug release property. It fits effectively in the mouth, resists saliva flushing and oral movements, provides oral drug delivery, and reduces patient discomfort. The Janus GPC adhesive hydrogels have great commercial potential to support further the development of innovative therapies for oral mucosal diseases.


Assuntos
Gelatina , Hidrogéis , Adesivos/química , Adesivos/farmacologia , Bandagens , Argila , Gelatina/química , Gelatina/farmacologia , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Indóis , Polímeros
19.
Front Pharmacol ; 13: 894832, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35860032

RESUMO

Secondary osteoporosis is triggered mostly by glucocorticoid (GC) therapy. Dexamethasone (DEX) was reported to inhibit osteogenic differentiation in zebrafish larvae and MC3T3-E1 cells in prior research. In this research, we primarily examined the protective impacts of epimedin C on the osteogenic inhibition impact of MC3T3-E1 cells and zebrafish larvae mediated by DEX. The findings illustrated no apparent toxicity for MC3T3-E1 cells after administering epimedin C at increasing dosages from 1 to 60 µM and no remarkable proliferation in MC3T3-E1 cells treated using DEX. In MC3T3-E1 cells that had been treated using DEX, we discovered that epimedin C enhanced alkaline phosphatase activities and mineralization. Epimedin C could substantially enhance the protein expression of osterix (OSX), Runt-related transcription factor 2 (RUNX2), and alkaline phosphatase (ALPL) in MC3T3-E1 cells subjected to DEX treatment. Additionally, epimedin C stimulated PI3K and AKT signaling pathways in MC3T3-E1 cells that had been treated using DEX. Furthermore, in a zebrafish larvae model, epimedin C was shown to enhance bone mineralization in DEX-mediated bone impairment. We also found that epimedin C enhanced ALPL activity and mineralization in MC3T3-E1 cells treated using DEX, which may be reversed by PI3K inhibitor (LY294002). LY294002 can also reverse the protective impact of epimedin C on DEX-mediated bone impairment in zebrafish larval. These findings suggested that epimedin C alleviated the suppressive impact of DEX on the osteogenesis of zebrafish larval and MC3T3-E1 cells via triggering the PI3K and AKT signaling pathways. Epimedin C has significant potential in the development of innovative drugs for the treatment of glucocorticoid-mediated osteoporosis.

20.
Bioact Mater ; 13: 53-63, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35224291

RESUMO

Guided bone regeneration membranes have been effectively applied in oral implantology to repair bone defects. However, typical resorbable membranes composed of collagen (Col) have insufficient mechanical properties and high degradation rate, while non-resorbable membranes need secondary surgery. Herein, we designed a photocrosslinkable collagen/polycaprolactone methacryloyl/magnesium (Col/PCLMA/Mg) composite membrane that provided spatiotemporal support effect after photocrosslinking. Magnesium particles were added to the PCLMA solution and Col/PCLMA and Col/PCLMA/Mg membranes were developed; Col membranes and PCL membranes were used as controls. After photocrosslinking, an interpenetrating polymer network was observed by scanning electron microscopy (SEM) in Col/PCL and Col/PCL/Mg membranes. The elastic modulus, swelling behavior, cytotoxicity, cell attachment, and cell proliferation of the membranes were evaluated. Degradation behavior in vivo and in vitro was monitored according to mass change and by SEM. The membranes were implanted into calvarial bone defects of rats for 8 weeks. The Col/PCL and Col/PCL/Mg membranes displayed much higher elastic modulus (p < 0.05), and a lower swelling rate (p < 0.05), than Col membranes, and there were no differences in cell biocompatibility among groups (p > 0.05). The Col/PCL and Col/PCL/Mg membranes had lower degradation rates than the Col membranes, both in vivo and in vitro (p < 0.05). The Col/PCL/Mg groups showed enhanced osteogenic capability compared with the Col groups at week 8 (p < 0.05). The Col/PCL/Mg composite membrane represents a new strategy to display space maintenance and enhance osteogenic potential, which meets clinical needs.

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