994 resultados para APICAL PERIODONTITIS


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The Apical Membrane Antigen-1 (AMA-1) is a well-characterized and functionally important merozoite protein and is currently considered a major candidate antigen for a malaria vaccine. Previously, we showed that AMA-1 has an influence on cellular immune responses of malaria-naive subjects, resulting in an alternative activation of monocyte-derived dendritic cells and induction of a pro-inflammatory response by stimulated PBMCs. Although there is evidence, from human and animal malaria model systems that cell-mediated immunity may contribute to both protection and pathogenesis, the knowledge on cellular immune responses in vivax malaria and the factors that may regulate this immunity are poorly understood. In the current work, we describe the maturation of monocyte-derived dendritic cells of P. vivax naturally infected individuals and the effect of P. vivax vaccine candidate Pv-AMA-1 on the immune responses of the same donors. We show that malaria-infected subjects present modulation of DC maturation, demonstrated by a significant decrease in expression of antigen-presenting molecules (CD1a, HLA-ABC and HLA-DR), accessory molecules (CD40, CD80 and CD86) and Fc gamma RI (CD64) receptor (P <= 0.05). Furthermore, Pv-AMA-1 elicits an upregulation of CD1a and HLA-DR molecules on the surface of monocyte-derived dendritic cells (P=0.0356 and P=0.0196, respectively), and it is presented by AMA-1-stimulated DCs. A significant pro-inflammatory response elicited by Pv-AMA-1-pulsed PBMCs is also demonstrated, as determined by significant production of TNF-alpha, IL-12p40 and IFN-gamma (P <= 0.05). Our results suggest that Pv-AMA-1 may partially revert DC down-modulation observed in infected subjects, and exert an important role in the initiation of pro-inflammatory immunity that might contribute substantially to protection. (c) 2009 Elsevier Ltd. All rights reserved.

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In each of the title compounds, R[Ph(Cl)C=(H)C]TeCl(2), R = nBu (1) and Ph (2), the primary geometry about the Te(IV) atom is a pseudo-trigonal-bipyramidal arrangement, with two Cl atoms in apical positions, and the lone pair of electrons and C atoms in the equatorial plane. As the Te(IV) is involved in two, an intra- and an inter-molecular, Te center dot center dot center dot Cl interactions the coordination geometry might be considered as a Psi-pentagonal bipyramid in each case. In addition, in (2) there is a hint of a Te center dot center dot center dot pi interaction (Te center dot center dot center dot C = 3.911(3) A). The key feature in the crystal structure of both compounds is the formation of supramolecular chains mediated by Te center dot center dot center dot Cl contacts. (1): C(12)H(15)Cl(3)Te, triclinic, P (1) over bar, a = 5.9471 (11), b = 10.7826(22), c = 11.7983(19) angstrom, alpha = 75.416(12), beta = 78.868(13), gamma = 80.902(14)degrees, V = 713.6(2) angstrom(3), Z = 2, R(1) = 0.021; (2): C14HIIC13Te, orthorhombic, Pcab, a=7.7189(10), b=17.415(2), c=21.568(3)angstrom, V = 2899.3(6) angstrom(3), Z = 8, R(1) = 0.027.

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Pollen transport to a receptive stigma can be facilitated through different pollinators, which submits the pollen to different selection pressures. This study aimed to associate pollen and stigma morphology with zoophily in species of the tribe Phaseoleae. Species of the genera Erythrina, Macroptilium and Mucuna with different pollinators were chosen. Pollen grains and stigmas were examined under light microscopy (anatomy), scanning electronic microscopy (surface analyses) and transmission electronic microscopy (ultrastructure). The three genera differ in terms of pollen wall ornamentation, pollen size, pollen aperture, thickness of the pollen wall, amount of pollenkitt, pollen hydration status and dominant reserves within the pollen grain, while species within each genus are very similar in most studied characteristics. Most of these features lack relationships to pollinator type, especially in Erythrina and Mucuna. Pollen reserves are discussed on a broad scale, according to the occurrence of protein in the pollen of invertebrate- or vertebrate-pollinated species. Some pollen characteristics are more associated to semi-dry stigma requirements. This apical, compact, cuticularised and secretory stigma occurs in all species investigated. We conclude that data on pollen and stigma structure should be included together with those on floral morphology and pollinator behaviour for the establishment of functional pollination classes.

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Six antifungal agents at subinhibitory concentrations were used for investigating their ability to affect the growth and branching in Neurospora crassa. Among the antifungals herein used, the azole agent ketoconazole at 0.5 mu g/ml inhibited radial growth more than fluconazole at 5.0 mu g/ml while amphotericin B at 0.05 mu g/ml was more effective than nystatin at 0.05 mu g/ml. Morphological alterations in hyphae were observed in the presence of griseofulvin, ketoconazole and terbinafine at the established concentrations. The antifungal agents were more effective on vegetative growth than on conidial germination. Terbinafine markedly reduced growth unit length (GU) by 54.89%, and caused mycelia to become hyperbranched. In all cases, there was a high correlation between hyphal length and number of tips (r > 0.9). All our results showed highly significant differences by ANOVA, (p < 0.001, alpha = 0.05). Considering that the hyphal tip is the main interface between the fungus and its environment/through which enzymes and toxins are secreted and nutrients absorbed, it would not be desirable to obtain a hyperbranched mycelia with inefficient doses of antifungal drugs.

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Calcineurin plays an important role in the control of cell morphology and virulence in fungi. Calcineurin is a serine/threonine-specific protein phosphatase heterodimer consisting of a catalytic subunit A and a regulatory subunit B. A mutant of Aspergillus fumigatus lacking the calcineurin A (calA) catalytic subunit exhibited defective hyphal morphology related to apical extension and branching growth, which resulted in drastically decreased filamentation. Here, we investigated which pathways are influenced by A. fumigatus calcineurin during proliferation by comparatively determining the transcriptional profile of A. fumigatus wild type and Delta calA mutant strains. Our results showed that the mitochondrial copy number is reduced in the Delta calA mutant strain, and the mutant has increased alternative oxidase (aoxA) mRNA accumulation and activity. Furthermore, we identified four genes that encode transcription factors that have increased mRNA expression in the Delta calA mutant. Deletion mutants for these transcription factors had reduced susceptibility to itraconazole, caspofungin, and sodium dodecyl sulfate (SDS). (C) 2009 Elsevier Inc. All rights reserved.

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Background: Periodontal disease shares risk factors with cardiovascular diseases and other systemic inflammatory diseases. The present study was designed to assess the circulating matrix metalloproteinases (MMPs) from chronic periodontal disease patients and, subsequently, after periodontal therapy. Methods: We compared the plasma concentrations of MMP-2. MMP-3, MMP-8, MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2, and total gelatinolytic activity in patients with periodontal disease (n =28) with those of control subjects (n = 22) before and 3 months after non-surgical periodontal therapy. Results: Higher plasma MMP-3, MMP-8, and MMP-9 concentrations were found in periodontal disease patients compared with healthy controls (all P<0.05), whereas MMP-2, TIMP-1, and TIMP-2 levels were not different. Treatment decreased plasma MMP-8 and MMP-9 concentrations by 35% and 39%, respectively (both P<0.02), while no changes were found in controls. MMP-2, MMP-3, TIMP-1, and TIMP-2 remained unaltered in both groups. Plasma gelatinolytic activity was higher in periodontal disease patients compared with controls (P<0.001) and decreased after periodontal therapy (P<0.05). Conclusions: This study showed increased circulating MMP-8 and MMP-9 levels and proteolytic activity in periodontal disease patients that decrease after periodontal therapy. The effects of periodontal therapy suggest that it may attenuate inflammatory chronic diseases. (C) 2009 Published by Elsevier B.V.

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Background: Periodontal disease has been associated with many chronic inflammatory systemic diseases, and a common chronic inflammation pathway has been suggested for these conditions. However, few studies have evaluated whether periodontal disease, in the absence of other known inflammatory conditions and smoking, affects circulating markers of chronic inflammation. This study compared chronic inflammation markers in control individuals and patients with periodontal disease and observed whether non-surgical periodontal therapy affected inflammatory disease markers after 3 months. Methods: Plasma and serum of 20 controls and 25 patients with periodontal disease were obtained prior to and 3 months after non-surgical periodontal therapy. All patients were non-smokers, they did not use any medication, and they had no history or detectable signs and symptoms of systemic diseases. Periodontal and systemic parameters included probing depth, bleeding on probing, clinical attachment level, hematologic parameters, as well as the following inflammatory markers: interleukin (IL)-6, high-sensitivity C-reactive protein (hs-CRP), CD40 ligand, monocyte chemoattractant protein (MCP)-1, soluble P-selectin (sP-selectin), soluble vascular adhesion molecule (sVCAM)-1, and soluble intercellular adhesion molecule (sICAM)-1. Results: There were no differences in the hematologic parameters of the patients in the control and periodontal disease groups. Among the tested inflammatory markers, IL-6 concentrations were higher in the periodontal disease group at baseline compared to the controls (P=0.006). Therapy was highly effective (P<0.001 for all the analyzed clinical parameters), and a decrease in circulating IL-6 and hs-CRP concentrations was observed 3 months after therapy (P=0.001 and P=0.006, respectively). Our results also suggest that the CD40 ligand marker may have been different in the control and periodontal disease groups prior to the therapy (P=0.009). Conclusions: In apparently otherwise healthy patients, periodontal disease is associated with increased circulating concentrations of IL-6 and hs-CRP, which decreased 3 months after non-surgical periodontal therapy. With regard to the CD40 ligand, MCP-1, sP-selectin, sVCAM-1, and sICAM-1, no changes were seen in the periodontal disease group between baseline and 3 months after therapy. J Periodontol 2009;80:594-602.

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Neospora caninum is an Apicomplexan protozoan that has the dog as a definitive host and cattle (among other animals) as intermediate hosts. It causes encephalopathy in dogs and abortion in cows, with significant loss in worldwide livestock. As any Apicomplexan, the parasite invades the cells using proteins contained in the phylum-specific organelles, like the micronemes, rhoptries and dense granules. The aim of this study was the characterization of a homologue (denominated NcMIC2-like1) of N. caninum thrombospondin-related anonymous protein (NcMIC2), a micronemal protein previously shown to be involved in the attachment and connection with the intracellular motor responsible for the active process of invasion. A polyclonal antiserum raised against the recombinant NcMIC2-like1 functional core (thrombospondin and integrin domains) recognized the native form of NcMIC2-like1, inhibited the in vitro invasion process and localized NcMIC2-like1 at the apical complex of the parasite by confocal immunofluorescence, indicating its micronemal localization. The new molecule, NcMIC2-like1, has features that differentiates it from NcMIC2 in a substantial way to be considered a homologue dagger.

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The goal of this study is to produce oleanolic acid derivatives by biotransformation process using Mucor rouxii and evaluate their antimicrobial activity against oral pathogens. The microbial transformation was carried out in shake flasks at 30A degrees C for 216 h with shaking at 120 rpm. Three new derivatives, 7 beta-hydroxy-3-oxo-olean-12-en-28-oic acid, 7 beta,21 beta-dihydroxy-3-oxo-olean-12-en-28-oic acid, and 3 beta,7 beta,21 beta-trihydroxyolean-12-en-28-oic acid, and one know compound, 21 beta-hydroxy-3-oxo-olean-12-en-28-oic acid, were isolated, and the structures were elucidated on the basis of spectroscopic analyses. The antimicrobial activity of the substrate and its transformed products was evaluated against five oral pathogens. Among these compounds, the derivative 21 beta-hydroxy-3-oxo-olean-12-en-28-oic acid displayed the strongest activity against Porphyromonas gingivalis, which is a primary etiological agent of periodontal disease. In an attempt to improve the antimicrobial activity of the derivative 21 beta-hydroxy-3-oxo-olean-12-en-28-oic acid, its sodium salt was prepared, and the minimum inhibitory concentration against P. gingivalis was reduced by one-half. The biotransformation process using M. rouxii has potential to be applied to the production of oleanolic acid derivatives. Research and antimicrobial activity evaluation of new oleanolic acid derivatives may provide an important contribution to the discovery of new adjunct agents for treatment of dental diseases such as dental caries, gingivitis, and periodontitis.

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Messenger RNAs coding for growth factors and receptor tyrosine kinases were measured by quantitative competitive and by semi-quantitative reverse-transcription polymerase chain reaction in whole and dissected chick inner ears. The fibroblast growth factor (FGF) receptor 1 chick embryonic kinase (CEK) 1 was expressed in all structures examined (otocyst, hatchling whole cochlea, cochlear nerve ganglion, and cochlear and vestibular sensory epithelia), although slightly more heavily in the otocyst. The related fibroblast growth factor receptors CEK 2 and 3 were preferentially expressed in the nerve ganglion and in the vestibular sensory epithelium, respectively. FGF 1 mRNA was low in early development, increasing to mature levels at around embryonic age 11 days, while FGF2, mRNA was expressed at constant levels at all ages. In response to ototoxic damage, FGF1 mRNA levels were increased in the early damaged cochlear sensory epithelium. Immunohistochemistry for CEK1 showed that normal hair cells expressed the receptor heavily on the hair cell stereocilia, while with early damage, CEK1 came to be expressed heavily on the apical surfaces of the supporting cells. In normal chicks, the CEK4 and CEK8 eph-class receptor tyrosine kinases were expressed relatively heavily by the cochlear nerve ganglion, and CEK10 was expressed relatively heavily by the cochlear hair cell sensory epithelium. The results suggest that the FGF system may be involved in the response of the cochlear epithelium to ototoxic damage. The eph-class receptor tyrosine kinase CEK10 may be involved in cell interactions in the cochlear sensory epithelium, while CEK4 and CEK8 may play a role in the cochlear innervation.

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We have evaluated T-DNA mediated plant promoter tagging, with a left-border-linked promoterless firefly luciferase (luc) construct, as a strategy for the isolation of novel plant promoters. In a population of approximately 300 transformed tobacco plants, IO lines showed LUC activity, including novel tissue-specific and developmental patterns of expression. One line, showing LUC activity only in the shoot and root apical meristems, was further characterised. Inverse PCR was used to amplify a 1.5 kb fragment of plant DNA flanking the single-copy T-DNA insertion in this line. With the exception of a 249 bp highly repetitive element, this sequence is present as a single copy in the tobacco genome, and is not homologous to any previously characterised DNA sequences. Sequence analysis revealed the presence of several motifs that may be involved in transcriptional regulation. Transgenic tobacco plants transformed with a transcriptional fusion of this putative promoter sequence to the beta-glucuronidase (uidA) reporter gene, showed GUS activity confined to the shoot tip and mature pollen. This promoter may be useful to direct the expression of genes controlling the transition to flowering, or genes to reduce losses due to pests and stresses damaging plant apical meristems.

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The ultrastructure of the tegument and tegument-associated microorganisms of the gyliauchenid digenean Gyliauchen nahaensis is described by transmission and scanning electron microscopy. The tegument is devoid of surface spines and is characterized by a moderately folded apical membrane, abundant vesicles, basal mitochondria, a folded basal plasma membrane, and a thick basal matrix. Microorganisms form a dense biofilm on the tegument of the posterodorsal surface and the excretory papilla. At least 7 microbial morphotypes were identified, including eubacteria, spirochaetes, and nanobacteria.

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Hypoechinorhynchus robustus sp. n. is described from Notolabrus parilus (Richardson) (Labridae) from Pt Peron, Western Australia. It has a proboscis with 30 hooks arranged in ten longitudinal rows: 5 rows of a small apical spine, a large anterior hook and a small posterior spine, 5 rows of a large anterior hook, a middle spine and a posterior spine. The new species is distinguished from other species of the genus by having a set of 5 small apical spines anterior to the large hooks on the proboscis, by having lemnisci that barely extend beyond the proboscis receptacle and testes which are more adjacent than tandem. H. robustus also has robust trunk spines anteriorly. Re-examination of Hypoechinorhynchus alaeopis Yamaguti, 1939 (type species) revealed trunk spines that had been overlooked previously. The Hypoechinorhynchidae is made a junior synonym of Arhythmacanthidae because there is considerable overlap between the two family diagnoses, particularly in that both families have a proboscis armature that changes abruptly from small basal spines to large apical (or subapical if present) hooks. The genus Hypoechinorhynchus is placed in the subfamily Arhythmacanthinae because it has trunk spines and a spherical proboscis with few hooks (relative to other arhythmacanthid genera). It is also proposed that Heterosentis magellanicus (Szidat, 1950) be returned to the genus Hypoechinorhynchus since it was transferred to Heterosentis primarily because it had trunk spines. The other hypoechinorhynchid genus contained only Bolborhynchoides exiguus (Achmerov et Dombrowskaja-Achmerova, 1941) Achmerov, 1959 and is relegated to incertae sedis.

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In this study, we characterize the electrophysiological and morphological properties of spiny principal neurons in the rat lateral amygdala using whole cell recordings in acute brain slices. These neurons exhibited a range of firing properties in response to prolonged current injection. Responses varied from cells that showed full spike frequency adaptation, spiking three to five times, to those that showed no adaptation. The differences in firing patterns were largely explained by the amplitude of the afterhyperpolarization (AHP) that followed spike trains. Cells that showed full spike frequency adaptation had large amplitude slow AHPs, whereas cells that discharged tonically had slow AHPs of much smaller amplitude. During spike trains, all cells showed a similar broadening of their action potentials. Biocytin-filled neurons showed a range of pyramidal-like morphologies, differed in dendritic complexity, had spiny dendrites, and differed in the degree to which they clearly exhibited apical versus basal dendrites. Quantitative analysis revealed no association between cell morphology and firing properties. We conclude that the discharge properties of neurons in the lateral nucleus, in response to somatic current injections, are determined by the differential distribution of ionic conductances rather than through mechanisms that rely on cell morphology.

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Four ramosus mutants with increased branching at basal and aerial nodes have been used to investigate the genetic regulation of bud outgrowth in Pisum sativum L. (garden pea). Studies of long-distance signalling, xylem sap cytokinin concentrations, shoot auxin level, auxin transport and auxin response are discussed. A model of branching control is presented that encompasses two graft-transmissible signals in addition to auxin and cytokinin. Mutants rms1 through rms4 are not deficient in indole-3-acetic acid (IAA) or in the basipetal transport of this hormone. Three of the four mutants, rms1, rms3 and rms4, have very reduced cytokinin concentrations in xylem sap from roots. This reduction in xylem sap cytokinin concentration appears to be caused by a property of the shoot and may be part of a feedback mechanism induced by an aspect of bud outgrowth. The shoot-to-root feedback signal is unlikely to be auxin itself, as auxin levels and transport are not correlated with xylem sap cytokinin concentrations in various intact and grafted mutant and wild-type plants. Rms1 and Rms2 act in shoot and rootstock to regulate the level or transport of graft-transmissible signals. Various grafting studies and double mutant analyses have associated Rms2 with the regulation of the shoot-to-root feedback signal. Rms1 is associated with a second unknown graft-transmissible signal that is postulated to move in the direction of root-to-shoot. Exogenous auxin appears to interact with both of the signals regulated by Rms1 and Rms2 in the inhibition of branching after decapitation. The action of Rms3 and Rms4 is less apparent at this stage, although both appear to act largely in the shoot.