948 resultados para Reactions of (Anthracen-9-yl)methylsulphanes with DMAD


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Paracoccidioides brasiliensis is the etiologic agent of the Paracoccidioidomycosis the most common systemic mycosis in Latin America. Little is known about the regulation of genes involved in the innate immune host response to P. brasiliensis. We therefore examined the kinetic profile of gene expression of peritoneal macrophage infected with P. brasiliensis. Total RNA from macrophages at 6, 24 and 48 h was extracted, hybridized onto nylon membranes and analyzed. An increase in the transcription of a number of pro-inflammatory molecules encoding membrane proteins, metalloproteases, involved in adhesion and phagocytosis, are described. We observed also the differential expression of genes whose products may cause apoptotic events induced at 24 h. In addition, considering the simultaneous analyses of differential gene expression for the pathogen reported before by our group, at six hours post infection, we propose a model at molecular level for the P. brasiliensis-macrophage early interaction. In this regard, P. brasiliensis regulates genes specially related to stress and macrophages, at the same time point, up-regulate genes related to inflammation and phagocytosis, probably as an effort to counteract infection by the fungus. (c) 2007 Elsevier Masson SAS. All fights reserved.

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The Epiphany (TM) Sealer is a new dual-curing resin-based sealer and has been introduced as an alternative to gutta-percha and traditional root canal sealers. The canal filling is claimed to create a seal with the dentinal tubules within the root canal system producing a `monoblock` effect between the sealer and dentinal tubules. Therefore, considering the possibility to incorporate the others adhesive systems, it is important to study the bond strength of the resulting cement. Forty-eight root mandibular canines were sectioned 8-mm below CEJ. The dentine discs were prepared using a tapered diamond bur and irrigated with 1% NaOCl and 17% EDTA. Previous the application Epiphany (TM) Sealer, the Epiphany (TM) Primer, AdheSE, and One Up Bond F were applied to the root canal walls. The LED and QTH (Quartz Tungsten Halogen) were used to photo-activation during 45 s with power density of 400 and 720 mW/cm(2), respectively. The specimens were performed on a universal testing machine at a cross-head speed of 1 mm/min until bond failure occurred. The force was recorded and the debonding values were used to calculate Push-out bond strength. The analysis of variance (ANOVA) and Tukey`s post-hoc tests showed significant statistical differences (P < 0.05) to Epiphany (TM) Sealer/Epiphany (TM) Primer/QTH and EpiphanyTM Sealer/AdheSE/QTH, which had the highest mean values of bond strength. The efficiency of resin-based filling materials are dependent the type of light curing unit used including the power density, the polymerization characteristics of these resin-based filling materials, depending on the primer/adhesive used.

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Purpose: To evaluate in vitro the solubility of the Epiphany endodontic filling material Epiphany (Pentron Clinical Technologies, Wallingford, CT) prepared with its resinous solvent. Methods: The specimens were prepared in the following experimental conditions: (1) GI, epiphany without photoactivation; (2) GII, Epiphany prepared with resinous solvent without photoactivation; (3) Gill, Epiphany followed by photoactivation; and (4) GIV, Epiphany prepared with resinous solvent followed by photoactivation. Ten specimens of each group were obtained from Teflon molds with 80% reduction in volume of the specimen`s dimensions based on American National Standard Institute/American Dental Association (ANSI/ADA) Specification No. 57. The samples were weighted and immersed in distilled water for 7 days. After this period, they were removed, dried, and weighed again. Solubility was calculated by using samples weight loss (%). The immersion liquid was evaluated through atomic absorption spectrometry. Results: The sealers without photoactivation were statistically similar (p > 0.05) between themselves (GI = 6.93% and GII = 6.39%) and different from the uncured sealers, which were statistically different between themselves (p < 0.05) (GIII = 3.56% and GIV = 0.47%). Only the Epiphany sealer prepared with resinous solvent followed by photoactivation presented solubility values within ANSI/ADA requirements, liberating the following amounts of ions: 114.43 mu g of Ca(2+)/mL, 2.4 mu g of Mg(2+)/mL, 0.33 mu g of Fe(2+)/mL, 0.11 mu 4g of Zn(2+)/mL, 1.31 mu g of Ni(2+)/mL, and 7.1 mu g of Na(+)/mL. Conclusion: The association of resinous solvent to the Epiphany sealer followed by photoactivation resulted in a filling material with low solubility and expressive liberation of calcium ions. (J Endod 2009;35:715-718)

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Introduction: A common complication during the restoration of severely destroyed teeth is the loss of coronal root dentine. The aim of this study was to evaluate the influence of different sealers on the bonding interface of weakened roots reinforced with resin and fiber posts. Methods: Sixty extracted maxillary canines were used. The crowns were removed, and the thickness of root dentine was reduced in the experimental (n = 40) and positive control (n = 10) groups. The specimens of experimental group were assigned to four subgroups (n = 10) according to the filling material: gutta-percha + Grossmann`s sealer, gutta-percha + AH Plus (Dentsply De Trey Gmbh, Konstanz, Germany), gutta-percha + Epiphany (Pentron Clinical Technologies, Wallingford, CT), and Resilon (Resilon Research LLC, Madison, CT) + Epiphany. In the negative control group (n = 10), canals were not filled. After post space preparation, the roots were restored with composite resin light-activated through a translucent fiber post. After 24 hours, specimens were transversally sectioned into 1-mm-thick slices. Push-out test and scanning electron microscopic (SEM) analyses of different regions were performed. Data from push-out test were analyzed by using Tukey post hoc multiple comparison tests. The percentage of failure type was calculated. Data from SEM analysis were compared by Friedman and Kruskal-Wallis tests (alpha = 0.05). Results: The mean bond strength was significantly higher in the negative control group as compared with the other groups (P < .05). In all groups, the most frequent type of failure was adhesive. Overall, apical and middle regions presented a lower density of resin tags than the coronal region (P < .05). Conclusions: The push-out bond strength was not affected by sealer or region. The canal region affected significantly the resin tag morphology and density at the bonding interface. (J Endod 2011;37:531-537)

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Introduction: Resin-bonded extracoronal attachments may be indicated for the abutment teeth of removable partial dentures, especially for anterior teeth when a cingulum rest must be provided. This type of treatment has a series of advantages such as minimal tooth reduction, supragingival margins, favourable stress distribution, and improved aesthetic appearance. Objective: To report a clinical case of oral rehabilitation using a combination of resin-bonded extracoronal attachments joined by a Dolder bar with a removable partial denture. Case report: A 60-year-old male patient with only the canines in the maxillary arch was restored with a combination of resin-bonded extracoronal attachments joined by a Dolder bar and a removable partial denture. Conclusion: Dentures with resin-bonded extracoronal attachments can have a number of advantages over traditional clasp-retained removable partial dentures.

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Purpose : Despite increased interest in quality of life (QOL) as an outcome measure and as a means of identifying client needs in health care, its conceptualisation and the identification of its constituents have been poorly researched for elderly people with stroke in Hong Kong. Method: This article analysed the literature to identify components relevant to the QOL of Chinese elderly people with stroke living in the community in Hong Kong. Results : While common components of QOL for elderly people with and without stroke and regardless of cultural background were identified, a number were specific to an elderly Chinese stroke population. Conclusion : Recommendations for future research have been made with reference to further exploring and validating these components for the target population. A clear understanding of these aspects is essential for the development of sensitive QOL measures to guide and evaluate service delivery to this population.

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Polarized absorption and emission spectra of trigonal single crystals of an Er(III) complex coordinated to a heptadentate tripodal ligand are reported at temperatures between 8 and 298 K. The assigned energy levels below the onset of ligand absorption (< 25 000 cm(-1)) are fitted to a parametrized electronic Hamiltonian. The C-3 site symmetry of the Er(HI) ion requires eight parameters for a full description of the ligand field within a one-electron operator description. This compound shows unusually large splittings of the multiplets, and the fitted parameters imply that this heptadentate ligand imparts the largest ligand field reported for an Er(III) complex. The ligand field was also interpreted within the angular overlap model (AOM). We derive the AOM matrix to include both sigma and anisotropic pi bonding and show that a useful description of the C-3 ligand field can be made using only five parameters. The success of the AOM description is encouraging for applications on isomorphous complexes within the lanthanide series and in describing the ligand field of low-symmetry complexes with less parameters than in the usual spherical harmonic expansion.

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To compare pathologic features of the cancers arising after different types of benign breast disease (BBD), we reviewed the invasive breast cancer slides of 169 women with a previous benign biopsy result. Lesions were categorized previously as nonproliferative, proliferative without atypia, or atypical hyperplasia. Pathologic features of the cancers were evaluated without knowledge of the previous BBD category. Estrogen and progesterone receptor immunohistochemistry was performed on available tissue blocks. The median times between a benign result and cancer were 100, 124, and 92 months for women with nonproliferative lesions, proliferative lesions without atypia, and atypical hyperplasia, respectively. Cancers in the 3 groups did not differ significantly in tumor size, axillary lymph node status, or histologic grade, and there was no significant difference in the distribution of histologic types of breast cancer. Lymphatic vessel invasion, extensive intraductal component, and hormone receptor status did not differ among BBD categories. The pathologic features of breast cancers that develop in women with a previous benign biopsy result do not vary according to the histologic category of the previous BBD.

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The composition of the Pyrgulidae and its relationships to other member families of the caenogastropod superfamily Rissooidea are examined after a consideration of new anatomical (including gross anatomy, sperm ultrastructure), conchological (including protoconch features), ecological, biogeographical and palaeontological data and a re-evaluation of existing literature. Pyrgulidae can be distinguished from hydrobiids unequivocally only with the aid of the radula. Sperm ultrastructural features suggest a very close relationship between the Pyrgulidae, the Hydrobiidae and the Bithyniidae (in fact no family-diagnostic sperm characters can be found to separate these three taxa). Based upon neontological and fossil evidence it is likely that pyrgulids represent a Miocene offshoot from a paratethyal hydrobiid lineage. Pyrgulids may also represent the stock from which the baicaliids arose, in which case the Pyrgulidae must be considered a paraphyletic group. The huge biogeographic gap between the Caspian Sea and Lake Baikal is to some extent bridged by the finding of a Neogene pyrgulid from the Altai Mountains. An alternative scenario for the origin of baicaliids is presented.

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People with developmental disabilities are becoming an important part of the general practice population. Although they have a similar range of medical conditions to the general population, there are some important differences in prevalence, risk factors, presentation and management of particular conditions. We use gastro-oesophageal reflux to illustrate how developmental disability may affect the presentation, assessment and management of a common condition.

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While mutations of CDKN2A are associated with melanoma predisposition, the precise role of its gene product p16 in the development of sporadic melanoma is less clearly understood. We sought to determine the prevalence of p16 expression using immunohistochemical analysis in a population-based sample of melanoma tumours, and also to identify histological, phenotypic and environmental factors associated with the presence or absence of p16 expression. We conducted face-to-face interviews with 108 patients newly diagnosed with melanoma to ascertain their history of sun exposure, and recorded various phenotypic parameters. Paraffin sections of tumours from these patients were stained with an anti-p16 monoclonal antibody following antigen retrieval. Overall, 52 (48%) tumours expressed p16; nodular melanomas had significantly lower levels of p16 immunoreactivity than superficial spreading melanomas (P = 0.015). While no association was found between p16 expression and host phenotype, loss of p16 staining was associated with thicker lesions (p = 0.084) and a high mitotic index (P = 0.013). Taken together, these findings are consistent with loss of p16 being a late event in the progression of sporadic primary melanomas, being associated with tumours of a more aggressive nature. (C) 2002 Lippincott Williams Wilkins.