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91.
Background : The Parakanã is a group of Indians with cultural similarities to the extinct Tupi group. They are an isolated native population from East Brazilian Amazon. A number of different O alleles have been found at the blood group ABO locus in populations of several ethnic origins (Caucasians, Blacks, Amerindians). Aim : The present study describes the ABO blood group polymorphism gene of the Parakanã Indians. The Amerindian group was carefully selected for racial background. Subject and methods : The blood group polymorphism was analysed in genomic DNA from 62 Parakanã Indians. We determined the 261G deletion, the T646A and C771T mutations described in O 1variant and the G542A substitution, using PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism). Results : All Amerindians studied were homozygous for the 261G deletion. The frequencies of the T646A and C771T mutations in Parakanãs (0.65) were lower than that observed in Kayapo, Yanomama and Arara Indians (0.91) ( &#104 2 = 18.24; p-v < 0.001. The G542A substitution in Parakanãs was also lower (0.22) than in other tribes (0.42) ( &#104 2 = 9.73; p-v = 0.001). Conclusions : The different O alleles including the G542A mutation are not distributed homogeneously among all Amazonian Amerindians. Our results are in agreement with other genetic markers studied previously in Parakanã Indians, whose distinct genetic pattern differs from Europeans and even from other Amerindians.  相似文献   
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Journal of NeuroVirology - This study aims to characterize the acute neurological manifestations caused by DENV, ZIKV, and YFV during hospitalization; identify the risk factors associated with...  相似文献   
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ObjectivesTo investigate the relationship between the use of social networking sites (SNSs) on patient perceptions, acceptance, and expectations of treatment using temporary anchorage devices (TADs) and to compare differences between patients from the United Kingdom and Brazil.Materials and MethodsCross-sectional questionnaires were administered to 39 participants at orthodontic practices in the United Kingdom and Brazil about patients'' use of SNSs, exposure to TADs on SNSs, and thoughts on extractions, jaw surgery, or TADs as treatment options.ResultsUK patients prefer for clinicians to have SNS profiles (P = .022). Most UK and Brazilian patients want to see their clinician''s work online (76.7%) and use SNSs to get information about treatment options (76.6%). There was a statistically significant difference in Brazilian patients'' acceptance of TADs as a treatment option compared with UK patients, particularly if it meant avoiding extractions (P = .002), avoiding jaw surgery (P = .004), or reducing treatment time (P = .010). Knowledge of TADs was greater in Brazilian patients (P < .001).ConclusionsPatients use SNSs to obtain information about treatments and prefer clinicians to have social media accounts. Patients exposed to TADs on SNSs are more likely to accept them as an orthodontic treatment option. UK patients have less knowledge of TADs and are therefore less sure to consider TADs as an option. Brazilian patients are more confident in considering the use of TADs. Clinicians should consider increasing their social media presence to accommodate patients'' expectations and acceptance of TADs.  相似文献   
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Statement of problemHow the polymerization shrinkage, loading, and mechanical properties of luting materials affect the shrinkage and functional stresses in ceramic laminate veneers (CLVs) with and without tooth preparation is unclear.PurposeThe purpose of this finite element analysis (FEA) study was to evaluate the effect of the polymerization shrinkage, functional loading, and mechanical properties of different luting materials on the stresses in ultrathin 0.3-mm CLVs with and without tooth preparation.Material and methodsThree resin cements, RelyX Veneer (RV), Allcem Veneer APS (AV), Variolink Esthetic LC (VE), and 1 flowable composite resin, Tetric N-Flow (TF), were tested for post-gel shrinkage (Shr), Knoop hardness (KHN), elastic modulus (E), compressive strength (CS), and diametral tensile strength (DTS). IPS e.max CAD disks of 0.3-mm thickness were made for simulating the effects of light attenuation. Eight 2-dimensional finite element models (Marc-Mentat) of a maxillary central incisor were generated to evaluate the polymerization shrinkage stress of different materials for luting 0.3-mm CLVs with or without tooth preparation and the stress during functional loading by using a modified von Mises criterion (mvm). Collected data from Shr, KHN, and E were submitted to 2-way ANOVA and the Tukey HSD test (α=.05).ResultsLight attenuation by the 0.3-mm ceramic disk did not significantly affect the E values, but Shr was significantly lower in VE (26%) and TF (35%). TF had lower volumetric Shr (%) when interposing a ceramic disk (0.31%). Both tested tooth preparation options showed similar stress distributions from polymerization shrinkage or functional loading, with higher stress concentration on the incisal edge and also on the cervical surface. The model featuring tooth preparation and RV resin cement had the highest and VE the lowest stress levels.ConclusionsThe flowable composite resin had similar mechanical properties as the resin cements. The stress distribution from shrinkage and functional loading was similar for both techniques with or without tooth preparation.  相似文献   
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Abstract

During the last decades, studies exploring the role of microorganisms inhabiting human body in different scenarios have demonstrated the great potential of modulating them to treat and prevent diseases. Among the most outstanding applications, probiotics have been used for over a century to treat infections and inflammation. Despite the beneficial role of other probiotics, Lactobacillus and Bifidobacterium species are the most frequently used, and have been effective as a therapeutic option in the treatment/prevention of dental caries, periodontal diseases, urogenital infections, and gastrointestinal infections. Additionally, as gastrointestinal tract harbors a great diversity of microbial species that directly or indirectly modulate host metabolism and immune response, the influence of intestinal microbiota, one of the targets of therapies using probiotics, on the biology of immune cells can be explored to treat inflammatory disorders or immune-mediated diseases. Thus, it is not surprising that probiotics have presented promising results in modulating human inflammatory diseases such as type 1 diabetes, multiple sclerosis, rheumatoid arthritis and inflammatory bowel disease, among others. Hence, the purpose of this review is to discuss the potential of therapeutic approaches using probiotics to constrain infection and development of inflammation on human subjects.  相似文献   
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Clinical Oral Investigations - Androgenic anabolic steroids (AAS) abuse is a serious health problem associated to several systemic complications. Here, we evaluated the periodontal clinical status,...  相似文献   
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The aim of this study was to compare, by micro‐computed tomography (micro‐CT) analysis, the obturation quality of two filling methods: the single‐cone technique with the bioceramic EndoSequence BC sealer and the continuous wave technique with the resin‐based AH Plus sealer. Twenty mandibular molars were divided into two groups (n = 10) according to the sealer used. Only the mesial roots, which are known to have mostly two canals, were used. The specimens were scanned before and after instrumentation and after obturation. Root canal volume after instrumentation and filling volume were calculated to obtain the percentage volumes of filling, voids and gaps. All specimens presented final volumes that were smaller than the initial volumes (P < 0.05). There was no significant difference between groups for filling volume, voids and gaps (P > 0.05). Using two filling methods, EndoSequence BC and AH Plus promoted a similar root filling quality in mesial roots of mandibular molars. Neither sealer was able to fill the root canal system completely.  相似文献   
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