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51.
ObjectiveTo evaluate the influence of a midline diastema on dentofacial esthetic perceptions of orthodontists, restorative dental specialists or prosthodontists, and laypersons in a frontal facial evaluation performed by means of video.Materials and MethodsTwo individuals aged between 20 and 25 years, one of each gender, with presence of a midline diastema were selected. An acrylic resin mockup was made of the maxillary anterior region, simulating ideal conditions of smile esthetics. Four standardized frontal view videos of the complete face were filmed of each individual in the following situations: with the ideal smile (unchanged mockup) and with the presence of midline diastemas of 0.5, 1.0, and 1.5 mm created by the mockup. In all videos, the patient said a certain sentence and, at the end, simulated a posed smile. Dentofacial esthetic perceptions of all four videos of each individual were evaluated by 51 orthodontists, 51 restorative dental specialists or prosthodontists, and 51 laypersons by means of visual analog scales. Data were evaluated using analysis of variance and Tukey post hoc test, with the level of significance set at 5%.ResultsThe most attractive videos for all groups of examiners were those without diastema and with a diastema of 0.5 mm, for both the woman and the man. For a diastema of 1 mm or 1.5 mm, the dentofacial characteristics were considered unesthetic.ConclusionsDiastemas equal to or greater than 1 mm negatively influence dentofacial esthetics in a frontal facial evaluation performed by means of video.  相似文献   
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In patients with Mansoni schistosomiasis, it is fundamental to evaluate the disease morbidity, which is reflected by the severity of periportal fibrosis (PPF) and parameters of portal hypertension, as analyzed by ultrasonography (US). This study aimed to evaluate the morbidity of schistosomiasis by hepatic and splenic point shear-wave elastography (pSWE) and relate this to US parameters. The PPF pattern, the diameter of the portal and splenic veins and the size of the spleen were evaluated by US. Then, liver and spleen pSWEs were assessed in 74 patients using the same equipment. As the PPF pattern progressed, the splenic pSWE values significantly increased. Significant correlations between splenic pSWE, the longitudinal and transverse lengths of the spleen and the diameters of the portal and splenic veins were observed. These findings, however, were not observed through hepatic pSWE. In conclusion, the splenic pSWE has the potential for assessing morbidity in schistosomiasis mansoni.  相似文献   
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Cementum is a mineralized tissue that lines the surface of the tooth root enabling attachment of the periodontal ligament to the root and surrounding alveolar bone. Studies examining the mechanisms involved in the formation of root cementum have been hindered by an inability to isolate and culture the cells required for cementum production (cementoblasts). This study isolated and characterized cementoblast cells derived from rat molar periodontal ligament. It was observed that the isolated cells expressed F‐Spondin, a cementoblast marker, while F‐Spondin expression was not observed in the cells of other tissues such as gingival fibroblasts and osteoblasts. As expected, the isolated cementoblast cells also expressed osteocalcin (OC), bone sialoprotein (BSP), alkaline phosphatase (ALP), and type I collagen, demonstrating the presence of mineralized tissues genes in cementoblast cells. These cells showed high ALP activity and calcified nodule formation in vitro. Since cementogenesis could be a critical event for regeneration of periodontal tissues, this study investigated whether bioactive glass particles could affect the proliferation of cementoblasts since they are known to enhance osteoblast proliferation. It was found that the ionic products from bioactive glass nanoparticles increased cementoblast viability, mitochondrial activity, and induced cell proliferation. Together, these results show the characterization of cementoblast cells from rat molar periodontal ligament. Additionally, it was shown that bioactive glass nanoparticles induced cementoblast to proliferate, indicating that they could be a potential material for use in cement regeneration through tissue engineering. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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Objectives To estimate, by neonatal screening, the birth prevalence of congenital toxoplasmosis among live‐born infants in Sergipe state, Brazil, and to investigate the clinical features of affected infants. Methods Dried blood spot specimens obtained from 15 204 neonates were assayed for the presence of anti‐T. gondii IgM antibodies. Duplicate retesting was done in infants with positive and borderline results. Confirmatory testing in peripheral blood samples consisted of testing for anti‐T. gondii IgG and IgM in infants and mothers. Those with possible congenital toxoplasmosis were evaluated and followed up to a median age of 20 months. Congenital infection was confirmed in the presence of persisting anti‐T. gondii IgG antibodies beyond 12 months of age. All infants with confirmed infection were treated with pyrimethamine, sulfadiazine and folinic acid for 1 year. Results Fifty‐three infants had detectable IgM in dried blood spot specimens. Confirmatory testing was reactive in 39/50, of which, 38 completed follow‐up. Six of 15 204 newborns were diagnosed with congenital toxoplasmosis, resulting in an estimated birth prevalence of four per 10 000 [CI 95% 1.4–8.0]. Four infants (67%) showed signs of congenital toxoplasmosis in their first year of life; three (75%) had retinochoroidal scars, and one had cerebral calcifications. Two infants remained asymptomatic until 20 months of age. Conclusions The birth prevalence of congenital toxoplasmosis is high in the Brazilian state of Sergipe, with most of the infants showing ocular lesions. Preventive measures are strongly warranted.  相似文献   
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Chronic rhinosinusitis is a disease of undefined etiology that significantly impacts the quality of life of its patients. Various studies carried out in countries other than Brazil have shown endoscopic sinus surgery as an effective means of treating this condition.ObjectiveThis study aims to analyze, with the aid of SNOT-20, the association between endoscopic sinus surgery and disease-specific quality of life of Brazilian patients treated for chronic rhinosinusitis accompanied or not by nasal polyps.Materials and MethodsThis prospective study enrolled patients submitted to endoscopic sinus surgery after drug therapy failed to improve their symptoms. They were assessed based on questionnaire SNOT-20p before and 12 months after surgery. Improvement on total scores and on the five items deemed more important by each patient were assessed. The study also looked into the correlation between preoperative scores and postoperative improvement and if there were any gender-related improvement differences.ResultsForty-three patients aged 44 (19), md (IQR), 65% of whom (26/43) were males. Statistically significant improvement was seen on SNOT-20 and SNOT-20(5+) and a correlation was established between preoperative scores and postoperative improved scores (p<0.001). No gender-related differences were observed in quality of life.ConclusionEndoscopic sinus surgery in patients with chronic rhinosinusitis is associated with statistically significant improvements in disease-specific quality of life.  相似文献   
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Background Cheilitis glandularis (CG) is a rare condition in which thick saliva is secreted from dilated ostia of swollen minor salivary glands from the lips. Aquaporins (AQPs) are membrane proteins that exhibit channel activity specific for water and small solutes. AQPs are essential for corporal homeostasis, and are widely expressed through human tissues. Most AQPs studies are based on renal and nervous pathophysiology; few involve salivary glands. Some previous investigators hypothesized that minor salivary gland structure and function is normal on CG. Objectives To study possible salivary synthesis alterations in CG, we compared the expression of AQPs present in minor salivary glands in specimens with CG and controls by using immunohistochemistry. Methods Seven cases of CG and three normal controls were studied. Results Intensity and patterns of expression of AQP 1, 2 and 8 differed in CG compared with controls. AQP 4 and 5 (the most important AQP in salivary function) showed identical patterns in CG and controls. Conclusion Our findings suggest that the expression and arguably, function of some of the AQPs may be altered in CG; consequently, water flow mechanism abnormalities with possible alteration in salivary composition seem to occur. External factors (mainly UV rays) seem to play an important role in CG; nonetheless, our findings suggest that there might be some degree of alteration on water transportation.  相似文献   
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