RESUMO
The purpose of this study was to evaluate the effect of different heat-treatment strategies for a ceramic primer on the shear bond strength of a 10-methacryloyloxydecyl-dihydrogen-phosphate (MDP)-based resin cement to a yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP) ceramic. Specimens measuring 4.5 × 3.5 × 4.5 mm(3) were produced from Y-TZP presintered cubes and embedded in polymethyl methacrylate (PMMA). Following finishing, the specimens were cleaned using an ultrasound device and distilled water and randomly divided into 10 experimental groups (n=14) according to the heat treatment of the ceramic primer and aging condition. The strategies used for the experimental groups were: GC (control), without primer; G20, primer application at ambient temperature (20°C); G45, primer application + heat treatment at 45°C; G79, primer application + heat treatment at 79°C; and G100, primer application + heat treatment at 100°C. The specimens from the aging groups were submitted to thermal cycling (6000 cycles, 5°C/55°C, 30 seconds per bath) after 24 hours. A cylinder of MDP-based resin cement (2.4 mm in diameter) was constructed on the ceramic surface of the specimens of each experimental group and stored for 24 hours at 37°C. The specimens were submitted to a shear bond strength test (n=14). Thermal gravimetric analysis was performed on the ceramic primer. The data obtained were statistically analyzed by two-way analysis of variance and the Tukey test (α=0.05). The experimental group G79 without aging (7.23 ± 2.87 MPa) presented a significantly higher mean than the other experimental groups without aging (GC: 2.81 ± 1.5 MPa; G20: 3.38 ± 2.21 MPa; G100: 3.96 ± 1.57 MPa), showing no difference from G45 only (G45: 6 ± 3.63 MPa). All specimens of the aging groups debonded during thermocycling and were considered to present zero bond strength for the statistical analyses. In conclusion, heat treatment of the metal/zirconia primer improved bond strength under the initial condition but did not promote stable bonding under the aging condition.
Assuntos
Cerâmica/química , Colagem Dentária , Metacrilatos/química , Cimentos de Resina/química , Ítrio/química , Zircônio/química , Adesividade , Varredura Diferencial de Calorimetria , Análise do Estresse Dentário/instrumentação , Temperatura Alta , Humanos , Umidade , Teste de Materiais , Metil n-Butil Cetona/química , Microscopia Eletrônica de Varredura , Resistência ao Cisalhamento , Estresse Mecânico , Propriedades de Superfície , Temperatura , Termogravimetria , Fatores de Tempo , terc-Butil Álcool/químicaRESUMO
Melioidosis, a severe infectious disease caused by Burkholderia pseudomallei that is prevalent in Southeast Asia and Northern Australia, has been sporadically reported in Brazil since 2003. We report a case of aortic aneurysm with blood culture positive for B. pseudomallei. The phylogenetic analysis of 16S ribosomal DNA showed this isolate to be evolutionarily grouped with the MSHR346 strains from Thailand.
Assuntos
Aneurisma Infectado/microbiologia , Burkholderia pseudomallei/genética , Burkholderia pseudomallei/isolamento & purificação , Melioidose/microbiologia , Idoso , Brasil , Humanos , Masculino , Melioidose/mortalidade , Filogenia , RNA Ribossômico 16S/genética , TailândiaRESUMO
Candida meningitis is a rare condition that occurs more frequently in premature infants, immunocompromised patients or patients after neurosurgery. We describe a case of a previously healthy 41-year-old man with Candida parapsilosis meningitis associated with oropharyngeal candidiasis as the first manifestation of AIDS.
Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/diagnóstico , Candida/isolamento & purificação , Candidíase Invasiva/diagnóstico , Candidíase Invasiva/patologia , Meningite Fúngica/diagnóstico , Meningite Fúngica/patologia , Adulto , Candida/classificação , Candidíase Bucal/diagnóstico , Candidíase Bucal/patologia , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Eletroforese em Gel de Ágar , Humanos , Masculino , Reação em Cadeia da PolimeraseRESUMO
Coccidioidomycosis is a systemic infection caused by the soil-dwelling dimorphic fungi Coccidioides spp. The disease is endemic in semiarid Northeast Brazil, where it is caused by C. posadasii. The aim of this study was to perform antifungal susceptibility tests of clinical and environmental strains of C. posadasii from Northeast Brazil. The in vitro activities of caspofungin, amphotericin B and azoles against clinical and environment isolates of C. posadasii were determined in accordance with the NCLLS M-38P macrodilution method. The antifungal susceptibility analysis showed that all the strains of C. posadasii (n = 10) were sensitive to caspofungin (16 microg/ml < or = MIC < or = 32 microg/ml), amphotericin B (0.0625 mug/ml < or = MIC < or = 0.125 microg/ml), ketoconazole (0.039 microg/ml < or = MIC < or = 0.156 microg/ml), itraconazole (0.125 microg/ml < or = MIC < or = 0.5 microg/ml), fluconazole (3.125 microg/ml < or = MIC < or = 6.25 microg/ml), and voriconazole (0.125 microg/ml). This study is the first description of in vitro antifungal susceptibility pattern of Brazilian strains of C. posadasii.