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71.
José Cotter Joana Magalh?es Francisca Dias de Castro Mara Barbosa Pedro Boal Carvalho Sílvia Leite Maria Jo?o Moreira Bruno Rosa 《World journal of gastrointestinal endoscopy》2014,6(8):359-365
AIM: To evaluate whether virtual chromoendoscopy can improve the delineation of small bowel lesions previously detected by conventional white light small bowel capsule endoscopy(SBCE). METHODS: Retrospective single center study. One hundred lesions selected from forty-nine consecutive conventional white light SBCE(SBCE-WL) examinations were included. Lesions were reviewed at three Flexible Spectral Imaging Color Enhancement(FICE) settings and Blue Filter(BF) by two gastroenterologists with ex-perience in SBCE, blinded to each other's findings, whoranked the quality of delineation as better, equivalent or worse than conventional SBCE-WL. Inter-observer percentage of agreement was determined and analyzed with Fleiss Kappa(k) coefficient. Lesions selected for the study included angioectasias(n = 39), ulcers/ero-sions(n = 49) and villous edema/atrophy(n = 12). RESULTS: Overall, the delineation of lesions was im-proved in 77% of cases with FICE 1, 74% with FICE 2, 41% with FICE 3 and 39% with the BF, with a percent-age of agreement between investigators of 89%(k = 0.833), 85%(k = 0.764), 66%(k = 0.486) and 79%(k = 0.593), respectively. FICE 1 improved the delineation of 97.4% of angioectasias, 63.3% of ulcers/erosions and 66.7% of villous edema/atrophy with a percentage of agreement of 97.4%(k = 0.910), 81.6%(k = 0.714) and 91.7%(k = 0.815), respectively. FICE 2 improved the delineation of 97.4% of angioectasias, 57.1% of ulcers/erosions and 66.7% of villous edema/atrophy, with a percentage of agreement of 89.7%(k = 0.802), 79,6%(k = 0.703) and 91.7%(k = 0.815), respectively. FICE 3 improved the delineation of 46.2% of angioecta-sias, 24.5% of ulcers/erosions and none of the cases of villous edema/atrophy, with a percentage of agreement of 53.8% [k = not available(NA)], 75.5%(k = NA) and 66.7%(k = 0.304), respectively. The BF improved the delineation of 15.4% of angioectasias, 61.2% of ulcers/erosions and 25% of villous edema/atrophy, with a per-centage of agreement of 76.9%(k = 0.558), 81.6%(k = 0.570) and 25.0%(k = NA), respectively.CONCLUSION: Virtual chromoendoscopy can improve the delineation of angioectasias, ulcers/erosions and villous edema/atrophy detected by SBCE, with almost perfect interobserver agreement for FICE 1. 相似文献
72.
Gleber-Netto FO Florêncio TN de Sousa SF Abreu MH Mendon?a EF Aguiar MC 《Journal of oral pathology & medicine》2012,41(8):603-609
J Oral Pathol Med (2012) 41: 603-609 Background: Mucoepidermoid carcinoma is the most common malignant tumor of salivary glands. This tumor is characterized by a great variability in clinical behavior, and little is known about the pathological mechanisms involved in its variance. Angiogenesis is an important step in tumor progression and is believed to be an essential event for metastatic dissemination. Methods: We aimed to investigate angiogenesis and lymphangiogenesis in mucoepidermoid carcinoma measuring the density of neoformed and lymphatic vessels using CD105 and D2-40 antibodies, respectively, and by immunohistochemical evaluation of VEGF-A and VEGF-C proteins. It was also investigated the expression of D2-40 in neoplastic cells. Results: We studied 26 cases of mucoepidermoid carcinoma, which showed great angiogenic activity measured by neoformed vessel density. However, a low density of lymphatics was observed. VEGF-A, VEGF-C, and D2-40 were commonly detected in mucoepidermoid carcinoma, but only VEGF-A expression correlated with neoformed vessel density. Recurrence and nodal metastasis were associated with low VEGF-A expression and low neoformed vessel density, indicating that impaired angiogenesis could lead to an aggressive phenotype. Conclusions: Angiogenesis seems important in the modulation of mucoepidermoid carcinoma pathogenesis; however, none of the parameters analyzed could predict tumor behavior. 相似文献
73.
Evaluation of mast cells in periapical cysts, dentigerous cysts, and keratocystic odontogenic tumors
de Noronha Santos Netto J Pires FR da Fonseca EC Silva LE de Queiroz Chaves Louren?o S 《Journal of oral pathology & medicine》2012,41(8):630-636
J Oral Pathol Med (2012) 41 : 630–636 Background: Several cell types are associated with the development of cystic and tumoral odontogenic lesions. Among inflammatory cells, mast cells can be associated with their pathogenesis. The aim of this study was to analyze mast cells in periapical cysts, dentigerous cysts, and keratocystic odontogenic tumors. Methods: Tissue sections were submitted to toluidine blue staining and immunohistochemistry with antibody anti‐tryptase (clone G3). Mast cells were quantitated using Image‐Pro Plus software to obtain the mean number of mast cells in three regions: epithelial, superficial portion of the fibrous wall and deep portion of the fibrous wall from 20 periapical cysts, 20 dentigerous cysts (six non‐inflamed and 14 inflamed) and 20 keratocystic odontogenic tumors (four non‐inflamed and 16 inflamed). Results: The mean number of mast cells detected per lesion by immunohistochemistry (4.1) was higher than by histochemistry (1.5) (P < 0.0001). Inflamed dentigerous cysts and keratocystic odontogenic tumors showed a higher mean number of mast cells than non‐inflamed lesions in all regions. The deep region from all cysts showed the highest mean number of degranulated mast cells, except for non‐inflamed keratocystic odontogenic tumors analyzed by immunohistochemistry. Conclusions: Immunohistochemical staining detected higher number of mast cells than histochemistry. The higher number of mast cells observed in inflamed lesions could indicate the participation of these cells in the inflammatory response in odontogenic lesions. The prevalence of degranulated mast cells in the deep region suggests intense activity of these cells, possibly related to growth of cystic lesions. 相似文献
74.
?zdemir S G?rgülü O Akba? Y Sel?uk T Sayar H Tarkan ? 《Journal of cranio-maxillo-facial surgery》2012,40(5):e137-e139
Rhinoliths are nasal stones that result from mineralisation of salts around an endogenous or exogenous nidus within the nasal cavity. They are uncommon nasal masses and usually unilateral and single, situated in the floor of the nose. The patient typically presents with nasal obstruction, facial pain and foul-smelling nasal secretion. To the best of our knowledge, the occurrence of squamous cell carcinoma with rhinolithiasis has not been previously reported in the English-language literature. In this article, we present a 63-year-old man, who had unilateral rhinolithiasis with squamous cell carcinoma within the nasal cavity. 相似文献
75.
Tissue losses within the nose due to various reasons result in the loss of normal anatomy and function. The external nasal valve area is one of the most important functional components of the nose. The columella, lobule, nostril, and alar region are among the components forming the external nasal valve area. Deformities of the nostrils are among the most frequently observed features that interfere with the functional anatomy of the nose. Malformations of the nostrils often emerge subsequent to cleft lip repairs. Stenoses are a common type of pathology among nostril deformities. In cases where a stenosis has formed, breathing problems and developmental anomalies may occur. In the patient with nostril stenosis presented in this report, there was a serious alar collapse and contracture subsequent to a cleft lip repair. In order to repair the nostril stenosis, a "boomerang flap" was chosen. This boomerang flap was used in combination with a nasolabial flap, a vestibular rotation flap, and a conchal cartilage graft to achieve a satisfactory repair. 相似文献
76.
Objective : To resolve if TBX22 mutations cause isolated tongue-tie in the Finnish population. Design : Mutation analysis of the coding region of the TBX22 gene in 50 Finnish isolated tongue-tie patients and 61 control samples. Results : One putative sequence variation was identified from two male patients, but whether this represents a polymorphism or causative mutation remains unknown. Conclusions : Mutations in the coding region of the TBX22 gene are not a major cause of ankyloglossia in the Finnish population and do not explain the sex difference or inheritance of tongue-tie. 相似文献
77.
Gurgel-Juarez NC de Almeida EO Rocha EP Freitas AC Anchieta RB de Vargas LC Kina S Fran?a FM 《Journal of prosthodontics》2012,21(3):160-166
Purpose: This study aimed to evaluate stress distribution on peri‐implant bone simulating the influence of platform switching in external and internal hexagon implants using three‐dimensional finite element analysis. Materials and Methods: Four mathematical models of a central incisor supported by an implant were created: External Regular model (ER) with 5.0 mm × 11.5 mm external hexagon implant and 5.0 mm abutment (0% abutment shifting), Internal Regular model (IR) with 4.5 mm × 11.5 mm internal hexagon implant and 4.5 mm abutment (0% abutment shifting), External Switching model (ES) with 5.0 mm × 11.5 mm external hexagon implant and 4.1 mm abutment (18% abutment shifting), and Internal Switching model (IS) with 4.5 mm × 11.5 mm internal hexagon implant and 3.8 mm abutment (15% abutment shifting). The models were created by SolidWorks software. The numerical analysis was performed using ANSYS Workbench. Oblique forces (100 N) were applied to the palatal surface of the central incisor. The maximum (σmax) and minimum (σmin) principal stress, equivalent von Mises stress (σvM), and maximum principal elastic strain (εmax) values were evaluated for the cortical and trabecular bone. Results: For cortical bone, the highest stress values (σmax and σvm) (MPa) were observed in IR (87.4 and 82.3), followed by IS (83.3 and 72.4), ER (82 and 65.1), and ES (56.7 and 51.6). For εmax, IR showed the highest stress (5.46e‐003), followed by IS (5.23e‐003), ER (5.22e‐003), and ES (3.67e‐003). For the trabecular bone, the highest stress values (σmax) (MPa) were observed in ER (12.5), followed by IS (12), ES (11.9), and IR (4.95). For σvM, the highest stress values (MPa) were observed in IS (9.65), followed by ER (9.3), ES (8.61), and IR (5.62). For εmax, ER showed the highest stress (5.5e‐003), followed by ES (5.43e‐003), IS (3.75e‐003), and IR (3.15e‐003). Conclusion: The influence of platform switching was more evident for cortical bone than for trabecular bone, mainly for the external hexagon implants. In addition, the external hexagon implants showed less stress concentration in the regular and switching platforms in comparison to the internal hexagon implants. 相似文献
78.
Purpose: The aim of this study was to evaluate the fracture strength of experimental hollow and solid design zirconia dowels. Materials and Methods: Three types of dowels (fiber‐reinforced composite [FRC], hollow design, and solid design zirconia dowels) were tested in the study (n = 10). A three‐point bending method was conducted, and a load was applied until fracture. The values were recorded as Newtons (N) and then converted to megapascals (MPa) according to the diameter of the dowels. Statistical analyses were performed using one‐way ANOVA and Tukey HSD tests. The significance was set at p < 0.05. Results: The mean fracture strength of the hollow design zirconia dowels was significantly higher (960.72 MPa) than solid zirconia dowels (741.78 MPa) and FRC dowels (687.64 MPa) (p < 0.05). Conclusions: The hollow design zirconia dowel seems to have sufficient fracture strength for anterior restorations. This design may be beneficial to access the apical region when retreatment is necessary, without any dowel‐removing procedure. 相似文献
79.
80.
Mar?o HF Panzarini SR Aranega AM Sonoda CK Poi WR Esteves JC Silva PI 《Dental traumatology》2012,28(4):306-313
Clinical experience has shown that most avulsed teeth are replanted after a long extra-alveolar time and dry or inadequate wet storage, causing necrosis of periodontal ligament cells. This condition invariably leads to development of external root resorption, leaving the filling material in contact with the periapical connective tissues. In this study, the periapical tissue reactions to calcium hydroxide (CH) and mineral trioxide aggregate (MTA) were evaluated after occurrence of external root resorption as an expected sequela of delayed tooth replantation. Twenty male Wistar rats (Rattus norvegicus, albinus) had their right upper incisor extracted and maintained in dry storage for 60 min. Then, the dental papilla, enamel organ, pulp tissue, and periodontal ligament were removed, and the teeth were immersed in a 2% acidulated phosphate sodium fluoride solution, pH 5.5, for 10 min. The teeth were randomly assigned into two groups (n = 10), in which the canals were filled with either a CH and saline paste (CH group) or MTA (MTA group). The sockets were irrigated with saline, and the teeth were replanted. After 80 days, it was possible to observe large areas of replacement root resorption and some areas of inflammatory root resorption in both groups. More severe inflammatory tissue reaction was observed in contact with calcium hydroxide compared with the mineral trioxide aggregate. New bone formation was more intense at the bottom of the socket in the MTA group. In conclusion, as far as periapical tissue compatibility is concerned, intracanal MTA can be considered as a viable option for root canal filling in delayed tooth replantation, in which external root resorption is an expected sequela. 相似文献