RESUMO
Currently, titanium and its alloys are the most used materials for biomedical applications. However, because of the high costs of these metals, new materials, such as niobium, have been researched. Niobium appears as a promising material due to its biocompatibility, and excellent corrosion resistance. In this work, anodized niobium samples were produced and characterized. Their capacity to support the osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BM-MSCs) was also tested. The anodized niobium samples were characterized by SEM, profilometry, XPS, and wettability. BM-MSCs were cultured on the samples during 14 days, and tested for cell adhesion, metabolic activity, alkaline phosphatase activity, and mineralization. Results demonstrated that anodization promotes the formation of a hydrophilic nanoporous oxide layer on the Nb surface, which can contribute to the increase in the metabolic activity, and in osteogenic differentiation of BM-MSCs, as well as to the extracellular matrix mineralization.
Assuntos
Diferenciação Celular/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Nióbio/farmacologia , Osteogênese/efeitos dos fármacos , Alicerces Teciduais , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/fisiologia , Células Cultivadas , Eletrólise , Feminino , Temperatura Alta , Teste de Materiais , Células-Tronco Mesenquimais/fisiologia , Nióbio/química , Oxirredução , Ratos , Ratos Endogâmicos SHR , Propriedades de Superfície , Alicerces Teciduais/químicaRESUMO
The genetic background of human populations can influence the susceptibility and outcome of infection diseases. Toll-like receptors (TLRs) have been previously associated with susceptibility to human immunodeficiency virus (HIV) infection, disease progression and hepatitis C, virus (HCV) co-infection in different populations, although mostly in Europeans. In this study, we investigated the genetic role of endosomal TLRs on susceptibility to HIV infection and HCV co-infection through the analysis of TLR7 rs179008, TLR8 rs3764880, TLR9 rs5743836 and TLR9 rs352140 polymorphisms in 789 Brazilian individuals (374 HIV+ and 415 HIV-), taking into account their ethnic background. Amongst the 357 HIV+ individuals with available data concerning HCV infection, 98 were positive. In European descendants, the TLR9 rs5743836 C carriers displayed a higher susceptibility to HIV infection [dominant, Odds Ratio (OR)=1.53; 95% CI: 1.05-2.23; P=0.027]. In African descendants, TLR9 rs5743836 CT genotype was associated with protection to HIV infection (codominant, OR=0.51; 95% CI: 0.30-0.87; P=0.013). Also, the TLR9 rs352140 AA variant genotype was associated with susceptibility to HIV+/HCV+ co-infection in African descendants (recessive, OR=2.92; 95% CI: 1.22-6.98, P=0.016). These results are discussed in the context of the different ethnic background of the studied individuals highlighting the influence of this genetic/ethnic background on the susceptibility to HIV infection and HIV/HCV co-infection in Brazilian individuals.
Assuntos
Infecções por HIV/genética , Hepatite C/genética , Receptor 7 Toll-Like/genética , Receptor 8 Toll-Like/genética , Receptor Toll-Like 9/genética , Adulto , População Negra , Brasil , Coinfecção , Endossomos/metabolismo , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , População BrancaRESUMO
PROBLEM: Mannose-binding lectin (MBL) is involved in the maintenance of an inflammatory environment in uterus. High MBL levels have been associated with successful pregnancies whereas low levels are involved in pre-eclampsia (PE) development. Here, we evaluated MBL2 gene polymorphisms in the structural and promoter regions addressing their association with PE. METHOD OF STUDY: DNA samples from 162 control pregnant women and 157 pregnant PE women were genotyped and data compared with demographic and clinical characteristics. RESULTS: High frequency of C and D alleles (related to low MBL levels) was observed in PE women when compared to controls (C: 0.08 versus 0.03, P = 0.006; D: 0.10 versus 0.05, P = 0.009). Grouping the MBL genotypes according to phenotype, a higher frequency of OO genotype was observed in PE women when compared to control women (0.15 versus 0.04, P = 0.007). CONCLUSION: Our data suggest that women with genotypes associated with low MBL levels could be potential PE developers.