932 resultados para proliferative lesions
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Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)
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The aim of this study was to determine the influence of thickness and aging on the intrinsic fluorescence of sealing materials and their ability to block fluorescence from the underlying surface as assessed using a laser fluorescence device. Cavities of 0.5 mm and 1 mm depth were drilled into acrylic boards which were placed over two surfaces with different fluorescence properties: a low-fluorescence surface, to assess the intrinsic fluorescence of the sealing materials, and a high-fluorescence surface, to assess the fluorescence-blocking ability of the sealing materials. Ten cavities of each depth were filled with different sealing materials: Adper Scotchbond Multi-Purpose, Adper Single Bond 2, FluroShield, Conseal f and UltraSeal XT Plus. Fluorescence was measured with a DIAGNOdent pen at five different time points: empty cavity, after polymerization, and 1 day, 1 week and 1 month after filling. The individual values after polymerization, as well as the area under the curve for the different periods were submitted to ANOVA and the Tukey test (p < 0.05). At 0.5 mm, Scotchbond, FluroShield and UltraSeal showed insignificant changes in intrinsic fluorescence with aging and lower fluorescence after polymerization than Single Bond and Conseal. At 1 mm, Scotchbond and FluroShield showed the lowest intrinsic fluorescence, but only Scotchbond showed no chagnes in fluorescence with aging. At both depths, Scotchbond blocked significantly less fluorescence. All sealing materials blocked more fluorescence when applied to a depth of 1 mm. At 0.5 mm, fissure sealants blocked more fluorescence than adhesives, and did not show significant changes with aging. Scotchbond had the least affect on the fluorescence from the underlying surface and would probably have the least affect on the monitoring of sealed dental caries by laser fluorescence.
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Introduction: Although Enterococcus faecalis is a member of the normal microbiota, it is also a major cause of nosocomial infections. Some strains of E. faecalis produce capsule, which contributes to pathogenesis through evasion of host defenses, and its production is dependent on the capsule (cps) operon polymorphism. This study investigated cps locus polymorphism in distinct lineages of E. faecalis isolated from canals of root-filled teeth with periapical lesions. Methods: Twenty-two E. faecalis isolates were evaluated regarding the cps operon polymorphism and genetic diversity. The 3 known CPS types were determined by polymerase chain reaction. This information was correlated with multilocus sequence typing data, which were used to define genetic lineages. Results: cpsA and cpsB were the only detected genes within the cps operon in 62.5% of E. faecalis strains (14/22), indicative of genotype CPS 1, which lacks capsule expression. The essential genes in the cps operon for capsule production were detected in the remaining strains, whereas 3 belonged to genotype CPS 5 and 5 strains to genotype CPS 2. A total of 14 sequence types (STs) were resolved in 22 E. faecalis isolates. Comparison with the E. faecalis international multilocus sequence typing database revealed that 9 STs were previously found, and that the 5 STs were novel. Conclusions: Certain E. faecalis genotypes from canals of root-filled teeth with periapical lesions belong to lineages associated with capsule expression and production of multiple virulence factors, which might account for their increased pathogenic potential. (J Endod 2012;38:58-61)
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Introduction: Human leukocyte antigen (HLA)-G is a nonclassic class I molecule that acts as a modulator of immune responses, and the expression of these molecules in virus-infected cells has been associated with subversion of the immune response. Objective: In this study, we performed a cross-sectional study, systematically comparing the expression of the HLA-G in benign, premalignant, and malignant oral lesions and correlating it with the presence of high-risk and low-risk human papillomavirus (HPV) types. Specimens and Methods: Oral biopsies were collected from 51 patients and analyzed by immunohistochemistry using anti HLA-G antibody. Human papillomavirus detection and typing from oral biopsies were obtained by polymerase chain reaction using GP5+/GP6+ and specific primers. Results: The 51 biopsies were stratified into 3 groups according to lesion grade: oral benign lesions (oral hyperplasia and papilloma, n = 16), oral premalignant lesions (oral leukoplakia with dysplasia and lichen planus, n = 17), and malignant lesions (oral squamous cell carcinoma, n = 18). Human leukocyte antigen G overexpression was mainly observed in benign and premalignant oral lesions but was not related to HPV infection (P>.05). On the other hand, HPV DNA was detected in 24 (47%) oral lesions, mainly in benign and premalignant lesions, with the most frequent type detected being high-risk HPV type. Conclusion: The HLA-G molecule was expressed in a significant number of benign oral lesions and was not correlated with HPV infection or oral cancer. Crown Copyright (C) 2012 Published by Elsevier Inc. All rights reserved.
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To prevent rejection of kidney transplants, patients must be kept in immunosuppressive therapy for a long time, which includes the use of drugs such as cyclosporine, azathioprine, cyclophosphamide, and prednisone. The action of these drugs reduces the general immune response of transplant patients and thus increases their susceptibility to infections. Moreover, these drugs increase the potential of developing lesions. Therefore, oral hygiene in kidney transplant recipients contributes to maintenance of the transplanted organ and its function. Thus, an investigation of oral lesions could be counted as a notable work. The aim of this study was to investigate oral lesions in a group of 21 kidney transplant patients under immunosuppressive therapy attended during a 1-year period in the Nephrology Department of the Federal University of Sergipe, Brazil. Data related to sex, age, etiology of renal disease, types of renal transplant, time elapsed after transplantation, immunosuppressive treatment, use of concomitant agents, and presence of oral lesions were obtained. All patients received a kidney transplant from a living donor, and the mean posttransplantation follow-up time was 31.6 months; 71.5% used triple immunosuppressive therapy with cyclosporine A, azathioprine, and prednisone. Ten patients were also treated with calcium-channel blockers. Of the 21 transplant patients, 17 (81%) presented oral lesions. Gingival overgrowth was the most common alteration, followed by candidiasis and superficial ulcers. One case of spindle cell carcinoma of the lower lip was observed. Oral cavity can harbor a variety of manifestations related to renal transplantation under immunosuppressive therapy.
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Molecular findings that confirmed the participation of ovine herpesvirus 2 (OVH-2) in the lesions that were consistent with those observed in malignant catarrhal fever of cattle are described. Three mixed-breed cattle from Rio Grande do Norte state demonstrated clinical manifestations that included mucopurulent nasal discharge, corneal opacity and motor incoordination. Routine necropsy examination demonstrated ulcerations and hemorrhage of the oral cavity, corneal opacity, and lymph node enlargement. Significant histopathological findings included widespread necrotizing vasculitis, non-suppurative meningoencephalitis, lymphocytic interstitial nephritis and hepatitis, and thrombosis. PCR assay performed on DNA extracted from kidney and mesenteric lymph node of one animal amplified a product of 423 base pairs corresponding to a target sequence within the ovine herpesvirus 2 (OVH-2) tegument protein gene. Direct sequencing of the PCR products, from extracted DNA of the kidney and mesenteric lymph node of one cow, amplified the partial nucleotide sequences (423 base pairs) of OVH-2 tegument protein gene. Blast analysis confirmed that these sequences have 98-100% identity with similar OVH-2 sequences deposited in GenBank. Phylogenetic analyses, based on the deduced amino acid sequences, demonstrated that the strain of OVH-2 circulating in ruminants from the Brazilian states of Rio Grande do Norte and Minas Gerais are similar to that identified in other geographical locations. These findings confirmed the active participation of OVH-2 in the classical manifestations of sheep associated malignant catarrhal fever.
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The histomorphometric and proliferative characteristics of the collared peccary (Tayassu tajacu) placenta and uterus were analyzed. The material was examined by standard histological techniques and histochemistry (PAS, Perls and Alcian Blue pH 0.5 and 2.5%) and the cellular proliferation by AgNORs and flow cytometry. All the analyzed morphometric variables differed between pregnant and non-pregnant uteri in the luteal phase using the Dunnet test. Height and gland diameter of uterine glands increased linearly during pregnancy, with an intense positive PAS and Perls reaction in all stages. The cells with more than seven AgNORs per nuclei and the cells in the G2M cell cycle phase in the maternal tissue also increased after 70 days of pregnancy. The uteroplacental ridges had a linear increase in size with two distinct areas, base and top, with uterine epithelium and trophoblastic cells changing their morphology following the placental ridge development. Flow cytometry analysis showed the percentage of cells in each cell cycle phase with a quadratic behavior for stages G2/M in the maternal tissue, suggesting an increase in proliferative capacity of maternal tissue after 65 days of pregnancy. The same quadratic effect was observed in the G0/G1 phase in both maternal and fetal tissues. Cells in apoptosis showed cubic behavior in both tissues. The morphometric and cellular dynamic aspects observed in this study have not been previously described and they extend our knowledge of functions relating to maternal-fetal dynamics in this species.
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Background. Dysfunction of the liver after transplantation may be related to the graft size and ischemia/reperfusion (I/R) injury. N-Acetylcysteine (NAC) exerts beneficial effects on livers undergoing ischemia reperfusion. We sought to evaluate NAC modulation on reduced livers associated with I/R injury. Methods. Male C57BL/6 mice of 8 weeks of age were divided into groups: 50% hepatectomy (G-Hep); NAC (G-Hep + NAC [150 mg/kg]) via vena cava 15 minutes before hepatectomy; ischemia (G-Hep + IR); NAC with hepatectomy (G-IR + Hep + Nac); and IR using 30 minutes selective hepatic occlusion and reperfusion for 24 hours. After 24 hours, the remaining liver was removed, for staining with hematoxylin and eosin or labeling by proliferating cell nuclear antigen. Blood was collected for biochemical evaluations. Significance was considered for P <= .05. Results. Aspartate aminotransferase was high in all studied groups reflecting the hepatectomy and intervention. injuries. However, when assessing alanine aminotransferase, which depicts liver function, induction of IR promoted a greater increase than hepatectomy (P = .0003). NAC decreased ALT activity in all groups, even in association with I/R (P < .05), reflecting a modulation of the injury. Necrosis resulting from IR was mitigated by NAC. The experimental model of 50% reduced live promoted regeneration of the hepatic remnant, which was accentuated by NAC, according to the total number of hepatocytes and PCNA values. Conclusion. NAC preserved the remnant liver in mice and stimulates regeneration even after IR injury.
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Background: In many types of cancer, prostaglandin E-2 (PGE(2)) is associated with tumour related processes including proliferation, migration, angiogenesis and apoptosis. However in gliomas the role of this prostanoid is poorly understood. Here, we report on the proliferative, migratory, and apoptotic effects of PGE(1), PGE(2) and Ibuprofen (IBP) observed in the T98G human glioma cell line in vitro. Methods: T98G human glioma cells were treated with IBP, PGE(1) or PGE(2) at varying concentrations for 24-72 hours. Cell proliferation, mitotic index and apoptotic index were determined for each treatment. Caspase-9 and caspase-3 activity was measured using fluorescent probes in live cells (FITC-LEHD-FMK and FITC-DEVD-FMK respectively). The migratory capacity of the cells was quantified using a scratch migration assay and a transwell migration assay. Results: A significant decrease was seen in cell number (54%) in the presence of 50 mu M IBP. Mitotic index and bromodeoxyuridine (BrdU) incorporation were also decreased 57% and 65%, respectively, by IBP. The apoptotic index was increased (167%) and the in situ activity of caspase-9 and caspase-3 was evident in IBP treated cells. The inhibition of COX activity by IBP also caused a significant inhibition of cell migration in the monolayer scratch assay (74%) and the transwell migration assay (36%). In contrast, the presence of exogenous PGE(1) or PGE(2) caused significant increases in cell number (37% PGE(1) and 45% PGE(2)). When mitotic index was measured no change was found for either PG treatment. However, the BrdU incorporation rate was significantly increased by PGE(1) (62%) and to a greater extent by PGE(2) (100%). The apoptotic index was unchanged by exogenous PGs. The addition of exogenous PGs caused an increase in cell migration in the monolayer scratch assay (43% PGE(1) and 44% PGE(2)) and the transwell migration assay (28% PGE(1) and 68% PGE(2)). Conclusions: The present study demonstrated that treatments which alter PGE(1) and PGE(2) metabolism influence the proliferative and apoptotic indices of T98G glioma cells. The migratory capacity of the cells was also significantly affected by the change in prostaglandin metabolism. Modifying PG metabolism remains an interesting target for future studies in gliomas.
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Oral Diseases (2012) 18, 673679 Objectives: The aim of this study was to investigate the relationship between podoplanin expression and proliferative activity of ameloblastomas and remnants of the odontogenic epithelium from dental follicles (DF) of unerupted teeth. Subjects and methods: Thirty-three paraffin-embedded ameloblastomas and thirty-two DF obtained of unerupted teeth were analyzed by immunohistochemistry using anti-human podoplanin and anti-Ki-67 antibodies. Podoplanin expression in odontogenic epithelial cells was evaluated using a scoring method, and the Ki-67 labeling index was determined by the percentage of positive odontogenic cells. Results: All ameloblastomas displayed podoplanin expression in ameloblast-like cells of the epithelial islands. Membranous expression of podoplanin in ameloblastomas was stronger than in the remnants of odontogenic epithelium (P = 0.001). Statistically significant difference was observed between the cytoplasmic and membranous expression of podoplanin in the remnants of odontogenic epithelium (P = 0.001). The index of epithelial odontogenic proliferative activity, verified by Ki-67 expression, was higher in ameloblastomas vs remnants of odontogenic epithelium (P < 0.001). No statistically significant correlation was identified between podoplanin and the cellular odontogenic proliferative activity in ameloblastomas and DF (P > 0.05). Conclusions: These results provide evidence that there is no connection between podoplanin immunostaining and odontogenic cellular proliferative activity and suggest a role for membranous podoplanin expression in the local invasion of ameloblastomas.
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Doxorubicin (DOX) is an important tumor chemotherapeutic agent, acting mainly by genotoxic action. This work focus on cell processes that help cell survival, after DOX-induced DNA damage. In fact, cells deficient for XPA or DNA polymerase eta (pol eta, XPV) proteins (involved in distinct DNA repair pathways) are highly DOX-sensitive. Moreover, LY294002, an inhibitor of PIKK kinases, showed a synergistic killing effect in cells deficient in these proteins, with a strong induction of G2/M cell cycle arrest. Taken together, these results indicate that XPA and pol eta proteins participate in cell resistance to DOX-treatment, and kinase inhibitors can selectively enhance its killing effects, probably reducing the cell ability to recover from breaks induced in DNA. (C) 2011 Elsevier Ireland Ltd. All rights reserved.
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Irnmunohistochcmical expression of BAX was evaluated in 24 canine cutaneous mast cell tumours in order to verify the relationship of this expression to the histopathological grade of the lesions and its prognostic value for clinical outcome. BAX expression increased with higher histopathological grades (P = 0.0148; P < 0.05 between grades I and III). Animals with high levels of BAX expression were 4.25 times more likely to die from the disease and had shorter post-surgical survival times (P = 0.0009). These results suggest that alterations in BAX expression may be related to the aggressiveness of canine cutaneous mast cell tumours, indicating that immunohistochemical detection of BAX may be predictive of clinical outcome. (C) 2011 Elsevier Ltd. All rights reserved.
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Objective To evaluate the perinatal outcomes in hydropic fetuses with congenital microcystic pulmonary lesions that underwent percutaneous, invasive, laser therapy. Method This retrospective study reviews the literature and our experience between 2004 and 2010. Characteristics of the cystic lung lesions, liquor volume (presence of polyhydramnios or not), localization of ablation (vascular vs interstitial) and gestational age at which the procedure was performed were related to outcome (survival). Results In total, 16 fetuses with congenital lung lesions underwent invasive percutaneous laser ablation, seven performed in our center and nine published cases. Survival rate was higher in fetuses with a subsequent postnatal diagnosis of bronchopulmonary sequestration (87.5%) compared with congenital adenomatoid malformation (28.6%; p?=?0.04). The technique of vascular ablation was more successful (100%) than interstitial ablation (25.0%, p?<?0.01). Conclusion Percutaneous vascular laser ablation seems to be effective for bronchopulmonary sequestration in hydropic fetuses. Outcomes were worst following interstitial ablation for microcystic congenital adenomatoid with hydrops. (C) 2012 John Wiley & Sons, Ltd.
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Objective: The purpose of this study was to analyse the use of digital tools for image enhancement of mandibular radiolucent lesions and the effects of this manipulation on the percentage of correct radiographic diagnoses. Methods: 24 panoramic radiographs exhibiting radiolucent lesions were selected, digitized and evaluated by non-experts (undergraduate and newly graduated practitioners) and by professional experts in oral diagnosis. The percentages of correct and incorrect diagnoses, according to the use of brightness/contrast, sharpness, inversion, highlight and zoom tools, were compared. All dental professionals made their evaluations without (T-1) and with (T-2) a list of radiographic diagnostic parameters. Results: Digital tools were used with low frequency mainly in T-2. The most preferred tool was sharpness (45.2%). In the expert group, the percentage of correct diagnoses did not change when any of the digital tools were used. For the non-expert group, there was an increase in the frequency of correct diagnoses when brightness/contrast was used in T-2 (p = 0.008) and when brightness/contrast and sharpness were not used in T-1 (p = 0.027). The use or non-use of brightness/contrast, zoom and sharpness showed moderate agreement in the group of experts [kappa agreement coefficient (kappa) = 0.514, 0.425 and 0.335, respectively]. For the non-expert group there was slight agreement for all the tools used (kappa <= 0.237). Conclusions: Consulting the list of radiographic parameters before image manipulation reduced the frequency of tool use in both groups of examiners. Consulting the radiographic parameters with the use of some digital tools was important for improving correct diagnosis only in the group of non-expert examiners. Dentomaxillofacial Radiology (2012) 41, 203-210. doi: 10.1259/dmfr/78567773
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The aim of this study was to evaluate the influence of dental plaque and moisture on performance of a laser fluorescence device in detecting occlusal and proximal caries lesions in primary teeth. Fifty-five occlusal and 58 proximal sites on primary molars were evaluated using a DIAGNOdent pen (LFpen) device. For the drying time study, the evaluations were performed in: (I) moist teeth; (II) teeth dried for 3 s, or (III) dried for 15 s. For the plaque study, the evaluations were done in sites: (I) without plaque; (II) with plaque, and (III) after cleaning. Evaluation of the teeth sections in stereomicroscope was the reference standard method. LF pen values, sensitivity, specificity, and accuracy were compared. The values obtained after 15 s of drying were higher than those obtained with moist teeth or dried for 3 s at both occlusal and proximal surfaces. However, there was no change in the performance in detecting caries lesions. With regard to the presence of plaque, there was no significant change in the readings of the device, but specificity was decreased in occlusal surfaces with plaque. At proximal surfaces, however, no significant differences were observed. In conclusion, the moisture conditions do not influence significantly the performance of the LFpen, but the presence of plaque can affect its performance in detecting occlusal caries lesions in primary teeth.