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1.
J Dent Res ; 103(4): 427-433, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38284313

RESUMO

The phosphate ester monomer 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) is capable of bonding to hydroxyapatite and, for this reason, is a key component of several self-etch adhesives. In this study, dicalcium phosphate dihydrate particles (DCPD; CaHPO4.2H2O) were functionalized with 10-MDP and used to formulate an experimental composite with 50 vol% inorganic content (3:1 DCPD:silanated barium glass ratio) dispersed in a BisGMA/TEGDMA matrix. The tested hypothesis was that DCPD functionalization would improve the composite's mechanical performance without compromising Ca2+ release. Composites containing nonfunctionalized DCPD or only reinforcing glass (in both cases, with or without 10-MDP mixed in the resin phase) were used as controls. Materials were tested for degree of conversion (DC; by Fourier transform infrared spectroscopy), water sorption (WS) and solubility (SL; according to ISO 4049), biaxial flexural strength (BFS)/modulus (FM) after 24 h and 5 mo in water, and 28-d Ca2+ release in water (by plasma-coupled optical emission spectroscopy). Data were analyzed using analysis of variance/Tukey test (alpha: 5%). DCPD functionalization did not interfere with DC. The composite containing functionalized DCPD showed significantly lower WS and SL in comparison with the material formulated with nonfunctionalized particles. The presence of 10-MDP (as a functionalizing agent or dispersed in the resin phase) reduced the composite's initial BFS and FM. After 5 mo in water, the composite with functionalized DCPD and both glass-only composites were able to maintain their mechanical properties at levels statistically similar to what was observed after 24 h. Ca2+ release was significantly reduced in both formulations containing 10-MDP. In conclusion, DCPD functionalization with 10-MDP increased the composite's resistance to hydrolytic degradation, improving its mechanical stability after prolonged water storage. However, the impaired water transit at the particle-matrix interface led to a reduction in Ca2+ release.


Assuntos
Resinas Compostas , Metacrilatos , Resinas Compostas/química , Teste de Materiais , Metacrilatos/química , Fosfatos de Cálcio/química , Água , Cálcio
2.
Braz J Med Biol Res ; 51(5): e6773, 2018 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-29590259

RESUMO

Bacterial infections occur worldwide and are a major public health problem. Among pathogens, Staphylococcus aureus is the main causative agent of bacterial diseases in the world. This study aimed to evaluate which components of the immune system could act protectively against a S. aureus infection in intradermally immunized mice. C57BL/6 and A/j mice were immunized intradermally with S. aureus inactivated by heat and then challenged with viable strains in an air pouch model. At 6, 12, and 24 h after the challenge, euthanasia was performed, and the cellular profile of the inflammatory infiltrate, cytokines, and the bacterial load were evaluated in the air pouch lavages. Immunized mice demonstrated that the intradermal immunization with S. aureus promoted protection in C57BL/6 mice by reducing the bacterial, which was correlated with increased serum concentration of IgG antibodies (IgG1 and IgG2a) against S. aureus. The increase in IgG2a antibody levels was correlated with a decrease of bacterial load in intradermally immunized C57BL/6 mice, along with production of IL-17A at the inflammation site, as well as IgG1consumption. Similar results were not found in the A/j lineage. In conclusion, a vaccine against S. aureus should focus more on the individual characteristics of the host because it is a determinant factor for the success of the immunization.


Assuntos
Anticorpos Antibacterianos/imunologia , Staphylococcus aureus Resistente à Meticilina/imunologia , Infecções Estafilocócicas/prevenção & controle , Vacinas Antiestafilocócicas/imunologia , Animais , Carga Bacteriana , Citocinas/imunologia , Modelos Animais de Doenças , Imunoglobulina G/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Infecções Estafilocócicas/imunologia , Vacinas Antiestafilocócicas/administração & dosagem , Fatores de Tempo
3.
Braz J Med Biol Res ; 50(12): e6211, 2017 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-29069223

RESUMO

Recent evidence suggests that cell-derived circulating miRNAs may serve as biomarkers of cardiovascular diseases. However, a few studies have investigated the potential of circulating miRNAs as biomarkers for left ventricular hypertrophy (LVH). In this study, we aimed to characterize the miRNA profiles that could distinguish hypertensive patients with LHV, hypertensive patients without LVH and control subjects, and identify potential miRNAs as biomarkers of LVH. LVH was defined by left ventricular mass indexed to body surface area >125 g/m2 in men and >110 g/m2 in women and patients were classified as hypertensive when presenting a systolic blood pressure of 140 mmHg or more, or a diastolic blood pressure of 90 mmHg or more. We employed miRNA PCR array to screen serum miRNAs profiles of patients with LVH, essential hypertension and healthy subjects. We identified 75 differentially expressed miRNAs, including 49 upregulated miRNAs and 26 downregulated miRNAs between LVH and control patients. We chose 2 miRNAs with significant differences for further testing in 59 patients. RT-PCR analysis of serum samples confirmed that miR-7-5p and miR-26b-5p were upregulated in the serum of LVH hypertensive patients compared with healthy subjects. Our findings suggest that these miRNAs may play a role in the pathogenesis of hypertensive LVH and may represent novel biomarkers for this disease.


Assuntos
Perfilação da Expressão Gênica/métodos , Hipertensão/sangue , Hipertrofia Ventricular Esquerda/sangue , MicroRNAs/sangue , Adulto , Idoso , Análise de Variância , Biomarcadores/sangue , Estudos de Casos e Controles , Regulação para Baixo , Feminino , Humanos , Hipertensão/genética , Hipertrofia Ventricular Esquerda/genética , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reação em Cadeia da Polimerase em Tempo Real , Padrões de Referência , Valores de Referência , Fatores de Risco , Regulação para Cima
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