961 resultados para Aggressive display
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Background: Herpesviruses may be related to the etiology of aggressive periodontitis (AgP) and chronic periodontitis (CP) by triggering periodontal destruction or by increasing the risk for bacterial infection. This case-control study evaluated the presence of herpes simplex virus type 1 (HSV-1), Epstein-Barr virus type 1 (EBV-1), human cytomegalovirus (HCMV), Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythia (previously T. forsythensis) in patients with generalized AgP (AgP group), CP (CP group), or gingivitis (G group) and in healthy individuals (C group). Methods: Subgingival plaque samples were collected with paper points from 30 patients in each group. The nested polymerase chain reaction (PCR) method was used to detect HSV-1, EBV-1, and HCMV. Bacteria were identified by 16S rRNA-based PCR. Results: HSV-1, HCMV, and EBV-1 were detected in 86.7%, 46.7%, and 33.3% of the AgP group, respectively; in 40.0%, 50.0%, and 46.7% of the CP group, respectively; in 53.3%, 40.0%, and 20.0% of the G group, respectively; and in 20.0%, 56.7%, and 0.0% of the C group, respectively. A. actinomycetemcomitans was detected significantly more often in the AgP group compared to the other groups (P<0.005). P. gingivalis and T. forsythia were identified more frequently in AgP and CP groups, and AgP, CP, and G groups had higher frequencies of P. intermedia compared to the C group. Conclusion: In Brazilian patients, HSV-1 and EBV-1, rather than HCMV, were more frequently associated with CP and AgP. J Periodontol 2008;79:2313-2321.
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This article reports the longitudinal follow-up of a familial case of aggressive periodontitis treated by a combined regenerative approach that consisted of root conditioning, bone grafting, and membrane positioning. Treatment resulted in attachment level gain, reduction of probing depth, absence of bleeding on probing, and complete bone filling of the defect. The short-term results obtained after surgery were maintained after 6 years, suggesting that the combined regenerative approach is able to completely arrest the disease with long-term stability. (Int J Periodontics Restorative Dent 2009; 29: 69-79.)
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Plants have multiple potassium (K+) uptake and efflux mechanisms that are expressed throughout plant tissues to fulfill different physiological functions. Several different classes of K+ channels and carriers have been identified at the molecular level in plants. K+ transporters of the HKT1 superfamily have been cloned from wheat (Triticum aestivum), Arabidopsis, and Eucalyptus camaldulensis. The functional characteristics as well as the primary structure of these transporters are diverse with orthologues found in bacterial and fungal genomes. In this report, we provide a detailed characterization of the functional characteristics, as expressed in Xenopus laevis oocytes, of two cDNAs isolated from E. camaldulensis that encode proteins belonging to the HKT1 superfamily of K+/Na+ transporters. The transport of K+ in EcHKT-expressing oocytes is enhanced by Na+, but K+ was also transported in the absence of Na+. Na+ is transported in the absence of K+ as has been demonstrated for HKT1 and AtHKT1. Overall, the E. camaldulensis transporters show some similarities and differences in ionic selectivity to HKT1 and AtHKT1. One striking difference between HKT1 and EcHKT is the sensitivity to changes in the external osmolarity of the solution. Hypotonic solutions increased EcHKT induced currents in oocytes by 100% as compared with no increased current in HKT1 expressing or uninjected oocytes. These osmotically sensitive currents were not enhanced by voltage and may mediate water flux. The physiological function of these osmotically induced increases in currents may be related to the ecological niches that E. camaldulensis inhabits, which are periodically flooded. Therefore, the osmosensing function of EcHKT may provide this species with a competitive advantage in maintaining K+ homeostasis under certain conditions.
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Several cystic fibrosis (CF) mouse models demonstrate an increased susceptibility to Pseudomonas aeruginosa lung infection, characterized by excessive inflammation and high rates of mortality. Here we developed a model of chronic P. aeruginosa lung disease in mice homozygous for the murine CF transmembrane conductance regulator G551D mutation that provides an excellent model for CF lung disease. After 3 days of infection with mucoid P. aeruginosa entrapped in agar beads, the G551D animals lost substantially more body weight than non-CF control animals and were less able to control the infection, harboring over 40-fold more bacteria in the lung. The airways of infected G551D animals contained altered concentrations of the inflammatory mediators tumor necrosis factor-alpha, KC/N51, and macrophage inflammatory protein-2 during the first 2 days of infection, suggesting that an ineffective inflammatory response is partly responsible for the clearance defect.
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Antibodies have the potential to be therapeutic reagents for malaria. Here we describe the production of a novel phage antibody display library against the C-terminal 19 kDa region of the Plasmodium yoelii YM merozoite surface protein-1 (MSP1(19)). In vivo studies against homologous lethal malaria challenge show an anti-parasite effect in a dose dependent manner, and analysis by plasmon resonance indicates binding to the antigen is comparable to the binding of a protective monoclonal antibody. The data support the lack of a need for any antibody Fc-related function and hold great significance for the development of a therapeutic reagent for malaria. (C) 2002 Elsevier Science Ltd. All rights reserved.
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PURPOSE: To determine the effects of aggressive lipid lowering on markers of ischemia, resistance vessel function, atherosclerotic burden, and Symptom status in patients with symptomatic coronary artery disease. METHODS: Sixty consecutive patients with coronary artery disease that was unsuitable for revascularization were assigned randomly to either usual therapy of lipids for patients with a low-density lipoprotein (LDL) cholesterol target level <116 mg/dL, or to a, more aggressive lipid-lowering strategy involving up to 80 mg/d of atorvastatin, with a target LDL cholesterol level <77 mg/dL. The extent and severity of inducible ischemia (by dobutamine echocardiography), vascular function.(brachial artery reactivity), atheroma burden (carotid intima-media thickness), and symptom status were evaluated blindly at baseline and after 12 weeks of treatment. RESULTS: After 12 weeks of treatment, patients in the aggressive therapy group had a significantly greater decrease in mean (+/- SD) LDL cholesterol level than those in the usual care group (29 +/- 38 mg/dL vs. 7 +/- 24 mg/dL, P = 0.03). Patients in the aggressive therapy group had a reduction in the number of ischemic wall segments (mean between-group difference of 1.3; 95% confidence interval: 0.1 to 2.0; P = 0.04), flow-mediated dilatation (mean between-group difference of 5.9%; 95% confidence interval: 2.5% to 9.4%; P = 0.001), and angina score after 12 weeks. There were no significant changes in atherosclerotic burden in either group. CONCLUSION: Patients with symptomatic coronary artery disease who are treated with aggressive lipid lowering have improvement of symptom status and ischemia that appears to reflect improved vascular function but not atheroma burden. Am J Med. 2003;114:445-453. (C) 2003 by Excerpta Medica Inc.
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Eight patients with heterozygous familial hypercholesterolemia who received combined long-term low-density lipoprotein apheresis and high-dose statin therapy showed a significant decrease in volume of coronary calcium over a period of 29 months as measured by, computed tomography. This suggests that the effects of aggressive lipid-lowering therapy can be assessed non-invasively and may be used as surrogate end points when testing new therapies.
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Prostate cancer (PCa) is one of the most incident cancers worldwide but clinical and pathological parameters have limited ability to discriminate between clinically significant and indolent PCa. Altered expression of histone methyltransferases and histone methylation patterns are involved in prostate carcinogenesis. SMYD3 transcript levels have prognostic value and discriminate among PCa with different clinical aggressiveness, so we decided to investigate its putative oncogenic role on PCa.We silenced SMYD3 and assess its impact through in vitro (cell viability, cell cycle, apoptosis, migration, invasion assays) and in vivo (tumor formation, angiogenesis). We evaluated SET domain's impact in PCa cells' phenotype. Histone marks deposition on SMYD3 putative target genes was assessed by ChIP analysis.Knockdown of SMYD3 attenuated malignant phenotype of LNCaP and PC3 cell lines. Deletions affecting the SET domain showed phenotypic impact similar to SMYD3 silencing, suggesting that tumorigenic effect is mediated through its histone methyltransferase activity. Moreover, CCND2 was identified as a putative target gene for SMYD3 transcriptional regulation, through trimethylation of H4K20.Our results support a proto-oncogenic role for SMYD3 in prostate carcinogenesis, mainly due to its methyltransferase enzymatic activity. Thus, SMYD3 overexpression is a potential biomarker for clinically aggressive disease and an attractive therapeutic target in PCa.
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HIV/AIDS-associated visceral leishmaniasis may display the characteristics of an aggressive disease or without specific symptoms at all, thus making diagnosis difficult. The present study describes the results of diagnostic tests applied to a series of suspected VL cases in HIV-infected/AIDS patients admitted in referral hospitals in Pernambuco, Brazil. From a total of 14 eligible patients with cytopenias and/or fever of an unknown etiology, and indication of bone marrow aspirate, 10 patients were selected for inclusion in the study. Diagnosis was confirmed by the following examinations: Leishmania detection in bone marrow aspirate, direct agglutination test, indirect immunofluorescence, rK39 dipstick test, polymerase chain reaction and latex agglutination test. Five out of the ten patients were diagnosed with co-infection. A positive direct agglutination test was recorded for all five co-infected patients, the Leishmania detection and latex agglutination tests were positive in four patients, the rK39 dipstick test in three, the indirect immunofluorescence in two and a positive polymerase chain reaction was recorded for one patient. This series of cases was the first to be conducted in Brazil using this set of tests in order to detect co-infection. However, no consensus has thus far been reached regarding the most appropriate examination for the screening and monitoring of this group of patients.
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Os raros tumores pituitários agressivos são chamados carcinomas quando são detectadas metástases, sejam sistêmicas e/ou em sistema nervoso central. Alguns casos estão associados com superprodução de hormônio, mas a maioria é diagnosticada em função dos sintomas locais. Essas neoplasias são geralmente refratárias aos tratamentos atuais. Uma mulher com 51 anos de idade apresentou dor de cabeça de início súbito, paralisia de braço esquerdo e hipoestesia facial esquerda. A tomografia e a ressonância magnética revelaram um tumor pituitário invadindo os seios esfenoidal e cavernoso esquerdos. Os dados laboratoriais excluíram hipersecreção hormonal. A paciente foi submetida à cirurgia transesfenoidal, e os achados histológicos mostraram uma neoplasia com Ki-67 estimado em 75%. As imagens excluíram tanto um tumor oculto primário quanto disseminação sistêmica ou do sistema nervoso central. Três semanas após a cirurgia, a condição neurológica apresentou piora com início de ataxia, ptose bilateral, oftalmoplegia e aumento do tamanho da lesão, levando à intervenção cirúrgica por craniotomia, seguida por apenas algumas sessões de radioterapia devido à progressão grave da doença. A paciente veio a óbito depois de quase dois meses das manifestações iniciais. O caso ilustra a agressividade de algumas lesões pituitárias, a eficácia limitada das modalidades atuais de tratamento, como a cirurgia ou a radioterapia, e as limitações da classificação atual de tumores pituitários. Até onde sabemos, esse caso corresponde a uma das neoplasias pituitárias mais agressivas descritas até hoje, com um nível muito alto de Ki-67 (75%) e sobrevida curta (2 meses). O nível de Ki-67 pode ser de valor prognóstico em tumores pituitários. A classificação da Organização Mundial da Saúde (OMS) para tumores pituitários deveria ser revisitada.
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Adult B-cell acute lymphoblastic leukemia remains a major therapeutic challenge, requiring a better characterization of the molecular determinants underlying disease progression and resistance to treatment. Here, using a phospho-flow cytometry approach we show that adult diagnostic B-cell acute lymphoblastic leukemia specimens display PI3K/Akt pathway hyperactivation, irrespective of their BCR-ABL status and despite paradoxically high basal expression of PTEN, the major negative regulator of the pathway. Protein kinase CK2 is known to phosphorylate PTEN thereby driving PTEN protein stabilization and concomitant PTEN functional inactivation. In agreement, we found that adult B-cell acute lymphoblastic leukemia samples show significantly higher CK2 kinase activity and lower PTEN lipid phosphatase activity than healthy controls. Moreover, the clinical-grade CK2 inhibitor CX-4945 (Silmitasertib) reversed PTEN levels in leukemia cells to those observed in healthy controls, and promoted leukemia cell death without significantly affecting normal bone marrow cells. Our studies indicate that CK2-mediated PTEN posttranslational inactivation, associated with PI3K/Akt pathway hyperactivation, are a common event in adult B-cell acute lymphoblastic leukemia and suggest that CK2 inhibition may constitute a valid, novel therapeutic tool in this malignancy.
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Dissertação para obtenção do Grau de Mestre em Engenharia Física