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Jos Pedro Martinho Sara Frana Siri Paulo Anabela Baptista Paula Ana Sofia Coelho Ana Margarida Abrantes Francisco Caramelo Eunice Carrilho Carlos Miguel Marto Maria Filomena Botelho Henrique Giro Manuel Marques-Ferreira 《Materials》2020,13(23)
(1) Aim: This study aims to analyze the in vitro infiltration of a silicate root canal sealer into dentinal tubules after using different endodontic irrigating solutions. (2) Methods: Twenty-nine teeth with single roots were separated into three groups according to the final irrigation protocol: G1 n = 10) = 17% EDTA (ethylenediaminetetraacetic acid) + 3.0% sodium hypochlorite (NaOCl), G2 (n = 10) = 17% EDTA + 2.0% chlorhexidine and G3 (Control group, n = 9) = 17% EDTA + saline solution. Root canals were filled using cold lateral compaction technique with MTA Fillapex sealer and gutta-percha. The sealer was labeled with rhodamine B. The teeth were segmented at the middle and third apical sections, which were visualized using 10× confocal laser microscopy to determine the sealer penetration percentage. (3) Results: In the apical section, no statistically significant differences were found between the groups regarding sealer penetration. In the middle section, Group 1 obtained the highest percentage, and Group 2 the lowest (p = 0.004). Group 1 also presented statistically significant differences in the Control Group (p = 0.031) and had close sealer penetration values. Meanwhile, the Control Group (p = 0.023) and Group 2 (p = 0.029) revealed a significant decrease of sealer penetration between the apical and middle sections. (4) Conclusion: The obtained results support that final irrigation with NaOCl promoted similar sealer penetration in the apical and middle sections. On the other hand, a significant decrease in the sealer penetration of the middle section was observed for the chlorhexidine and saline groups. Compared to other irrigant solutions, NaOCl promotes more uniform sealer penetration, which can correlate with better sealing and, consequently, higher endodontic treatment success. 相似文献
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José Pedro Pinto Agostinho Cordeiro Ana Margarida Ferreira Concei??o Antunes Patrícia Botelho Ana Jo?o Rodrigues Pedro Le?o 《World journal of gastroenterology : WJG》2014,20(36):13191-13194
Ileal intussusception is the invagination of the small intestine within itself and accounts for 1% of cases of acute obstruction. However, physicians do not initially consider intussusception as a possible diagnosis of obstruction due to its rarity in adults. Herein, we report the case of a 22-year-old male who was admitted to the Emergency Department with continuous abdominal pain. Ultrasonography and computed tomography revealed an ileal intussusception. The patient underwent surgical removal of the segment of the small bowel. Unexpectedly, pathology revealed that the invagination occurred due to a parasite egg, with features suggestive of Schistosoma species. Schistosomiasis, although considered a parasitic disease in tropical countries, is not absent from Europe and though it is highly improbable, it may be responsible for cases of intussusception in adults. 相似文献
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Christiane Mariotini-Moura Matheus Silva e Bastos Felipe Freitas de Castro Mellina Lanna Trindade Raphael de Souza Vasconcellos Myrian Augusta Araújo Neves-do-Valle Bernardo Pereira Moreira Ramon de Freitas Santos Claudia Miranda de Oliveira Luana Celina Seraphim Cunha Xênia Macedo Souto Gustavo Costa Bressan Abelardo Silva-Júnior Munira Muhammad Abdel Baqui Maria Terezinha Bahia Márcia Rogéria de Almeida José Roberto Meyer-Fernandes Juliana Lopes Rangel Fietto 《Acta tropica》2014
Previous work has suggested that Trypanosoma cruzi diphosphohydrolase 1 (TcNTPDase-1) may be involved in the infection of mammalian cells and serve as a potential target for rational drug design. In this work, we produced recombinant TcNTPDase-1 and evaluated its nucleotidase activity, cellular localization and role in parasite adhesion to mammalian host cells. TcNTPDase-1 was able to utilize a broad range of triphosphate and diphosphate nucleosides. The enzyme's Km for ATP (0.096 mM) suggested a capability to influence the host's ATP-dependent purinergic signaling. The use of specific polyclonal antibodies allowed us to confirm the presence of TcNTPDase-1 at the surface of parasites by confocal and electron microscopy. In addition, electron microscopy revealed that TcNTPDase-1 was also found in the flagellum, flagellum insertion region, kinetoplast, nucleus and intracellular vesicles. The presence of this enzyme in the flagellum insertion region and vesicles suggests that it may have a role in nutrient acquisition, and the widespread distribution of TcNTPDase-1 within the parasite suggests that it may be involved in other biological process. Adhesion assays using anti-TcNTPDase-1 polyclonal antibodies as a blocker or purified recombinant TcNTPDase-1 as a competitor revealed that the enzyme has a role in parasite–host cell adhesion. These data open new frontiers to future studies on this specific parasite–host interaction and other unknown functions of TcNTPDase-1 related to its ubiquitous localization. 相似文献
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Igor Bastos Polonio Milena Marques Pagliareli Acencio Rogério Pazetti Francine Maria de Almeida Bárbara Soares da Silva Karina Aparecida Bonifácio Pereira Rogério Souza 《Jornal brasileiro de pneumologia》2014,40(4):421-424
We assessed the effects of lodenafil on hemodynamics and inflammation in the rat
model of monocrotaline-induced pulmonary hypertension (PH). Thirty male
Sprague-Dawley rats were randomly divided into three groups: control; monocrotaline
(experimental model); and lodenafil (experimental model followed by lodenafil
treatment, p.o., 5 mg/kg daily for 28 days) Mean pulmonary artery pressure (mPAP) was
obtained by right heart catheterization. We investigated right ventricular
hypertrophy (RVH) and IL-1 levels in lung fragments. The number of cases of RVH was
significantly higher in the monocrotaline group than in the lodenafil and control
groups, as were mPAP and IL-1 levels. We conclude that lodenafil can prevent
monocrotaline-induced PH, RVH, and inflammation. 相似文献
67.
Silvana Neves Ferraz de Assun??o Carla Hilário da Cunha Daltro Ney Christian Boa Sorte Hugo da Costa Ribeiro Júnior Maria de Lourdes Bastos Cleriston Farias Queiroz Ant?nio Carlos Moreira Lemos 《Jornal brasileiro de pneumologia》2014,40(2):134-141
OBJECTIVE:
To describe lung function findings in overweight children and adolescents without respiratory disease.METHODS:
This was a cross-sectional study involving male and female overweight children and adolescents in the 8-18 year age bracket, without respiratory disease. All of the participants underwent anthropometric assessment, chest X-ray, pulse oximetry, spirometry, and lung volume measurements. Individuals with respiratory disease were excluded, as were those who were smokers, those with abnormal chest X-rays, and those with an SpO2 = 92%. Waist circumference was measured in centimeters. The body mass index-for-age Z score for boys and girls was used in order to classify the individuals as overweight, obese, or severely obese. Lung function variables were expressed in percentage of the predicted value and were correlated with the anthropometric indices.RESULTS:
We included 59 individuals (30 males and 29 females). The mean age was 11.7 ± 2.7 years. Lung function was normal in 21 individuals (35.6%). Of the 38 remaining individuals, 19 (32.2%), 15 (25.4%), and 4 (6.7%) presented with obstructive, restrictive, and mixed ventilatory disorder, respectively. The bronchodilator response was positive in 15 individuals (25.4%), and TLC measurements revealed that all of the individuals with reduced VC had restrictive ventilatory disorder. There were significant negative correlations between the anthropometric indices and the Tiffeneau index in the individuals with mixed ventilatory disorder.CONCLUSIONS:
Lung function was abnormal in approximately 65% of the individuals evaluated here, all of whom were overweight. Obstructive ventilatory disorder and positive bronchodilator response predominated. 相似文献68.
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