356 resultados para associated graded Lie algebra
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Indole-3-acetic acid (IAA), when oxidized by horseradish peroxidase (HRP), is transformed into cytotoxic molecules capable of inducing cell injury. The aim of this study was to test if, by targeting hematopoietic tumors with HRP-conjugated antibodies in association with IAA treatment, there is induction of apoptosis. We used two lineages of hematologic tumors: NB4, derived from acute promyelocytic leukemia (APL) and Granta-519 from mantle cell lymphoma (MCL). We also tested cells from 12 patients with acute myeloid leukemia (AML) and from 10 patients with chronic lymphocytic leukemia (CLL). HRP targeting was performed with anti-CD33 or anti-CD19 antibodies (depending on the origin of the cell), followed by incubation with goat anti-mouse antibody conjugated with HRP. Eight experimental groups were analyzed: control, HRP targeted, HRP targeted and incubated with 1, 5 and 10 mM IAA, and cells not HRP targeted but incubated with 1, 5 and 10 mM IAA. Apoptosis was analyzed by flow cytometry using annexin V-FITC and propidium iodide labeling. Results showed that apoptosis was dependent on the dose of IAA utilized, the duration of exposure to the prodrug and the origin of the neoplasia. Targeting HRP with antibodies was efficient in activating IAA and inducing apoptosis. (C) 2010 Elsevier Ltd. All rights reserved.
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Objective: Hantaviruses are rodent-borne RNA viruses that have caused hantavirus cardiopulmonary syndrome in several Brazilian regions. In the present study, geographical distribution, seroprevalence, natural host range, and phylogenetic relations of rodent-associated hantaviruses collected from seven counties of Southeastern Brazil were evaluated. Methods: ELISA, RT-PCR and phylogenetic analysis were used in this study. Results: Antibodies to hantavirus were detected in Bolomys lasiurus, Akodon sp. and Oligoryzomys sp., performing an overall seroprevalence of 5.17%. All seropositive rodents were associated with grasslands or woods surrounded by sugar cane fields. Phylogenetic analysis of partial S- and M-segment sequences showed that viral sequences isolated from B. lasiurus specimens clustered with Araraquara virus. However, a sequence from Akodon sp. shared 100% similarity with Argentinian/Chilean viruses based on the partial S- segment amino acid sequence. Conclusion: These results indicate that there are associations between rodent reservoirs and hantaviruses in some regions of Southeastern Brazil, and suggest the existence of additional hantavirus genetic diversity and host ecology in these areas. Copyright (C) 2008 S. Karger AG, Basel
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Cardiac sympathetic denervation and ventricular arrhythmia are frequently observed in chronic Chagas cardiomyopathy (CCC). This study quantitatively evaluated the association between cardiac sympathetic denervation and sustained ventricular tachycardia (SVT) in patients with CCC. Methods: We prospectively investigated patients with CCC and left ventricular ejection fraction (LVEF) greater than 35% with SVT (SVT group: n = 5 15; mean age +/- SD, 61 +/- 8 y; LVEF, 51% +/- 8%) and patients without SVT (non-SVT group: n = 11; mean age +/- SD, 55 +/- 10 y; LVEF, 57% +/- 10%). Patients underwent myocardial scintigraphy with (123)I-metaiodobenzylguanidine ((123)I-MIBG) for the evaluation of sympathetic innervation and resting perfusion with (99m)Tc-methoxyisobutylisonitrile ((99m)Tc-MIBI) for the evaluation of myocardial viability. A visual semiquantitative score was attributed for regional uptake of each radiotracer using a 17-segment left ventricular segmentation model (0, normal; 4, absence of uptake). A mismatch defect was defined as occurring in segments with a 99mTc-MIBI uptake score of 0 or 1 and a (123)I-MIBG score of 2 or more. Results: Compared with the non-SVT group, the SVT group had a similar (99m)Tc-MIBI summed score (6.9 +/- 7.5 vs. 4.4 +/- 5.2, respectively, P = 0.69) but a higher (123)I-MIBG summed score (10.9 +/- 7.8 vs. 22.4 +/- 9.5, respectively, P = 0.007) and a higher number of mismatch defects per patient (2.0 +/- 2.2 vs. 7.1 +/- 2.0, respectively, P < 0.0001). The presence of more than 3 mismatch defects was strongly associated with the presence of SVT (93% sensitivity, 82% specificity; P = 0.0002). Conclusion: In CCC, the amount of sympathetically denervated viable myocardium is associated with the occurrence of SVT. Myocardial sympathetic denervation may participate in triggering malignant ventricular arrhythmia in CCC patients with relatively well-preserved ventricular function.
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As the mechanisms leading to the persistence of hepatitis B virus (HBV) infection are poorly understood and as the histocompatibility leucocyte antigen (HLA)-G is well described as a tolerogenic molecule, we evaluated HLA-G expression in 74 specimens of HBV liver biopsies and in 10 specimens obtained from previously healthy cadaver liver donors. HBV specimens were reviewed and classified by the METAVIR score, and HLA-G expression was assessed by immunohistochemistry. No HLA-G expression was observed in control hepatocytes. In contrast, 57 (77%) of 74 HBV specimens showed soluble and membrane-bound HLA-G expression in hepatocytes, biliary epithelial cells or both. No associations between the intensity of HLA-G expression and patient age or gender, HBeAg status, severity of liver fibrosis, and grade of histological findings were observed. Although significance was not reached (P = 0.180), patients exhibiting HLA-G expression presented a higher median HBV DNA viral load (105 copies/mL) than those who did not express HLA-G (103.7 copies/mL). These results indicate that HLA-G is expressed in most cases of chronic HBV infection in all stages and may play a role in the persistency of HBV infection.
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In the present study, we analyzed AURKA and AURKB gene expression in 70 acute myeloid leukemia (AML) patients. There was no difference between leukemic samples and bone marrow mononuclear cells (BMMCs, n = 8) or CD34(+) progenitors (n = 10) from healthy donors. High white blood cells (WBC) counts were observed in the AURKA(+) and AURKB(+) groups, but no significant differences regarding age, gender, platelet counts or frequency of FLT3-ITD mutations. AURKA, but not AURKB, expression was independently associated with high WBC counts (OR: 3.15, 95% CI 1.07-9.24, p = 0.03). Moreover, the majority of cases that overexpressed AURKA and AURKB presented unfavorable cytogenetic abnormalities (p < 0.001). In conclusion, we described a significant association between overexpression of AURKA/B and cytogenetics findings in AML, which may be relevant to new therapeutic approaches, based on Aurora kinase inhibitors. (C) 2010 Elsevier Ltd. All rights reserved.
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Background Conflicting results have been reported in studies evaluating the relationship between serum markers of iron overload, liver iron deposits, and HFE mutations (C282Y and H63D) in chronic hepatitis C patients, and also their impact on the response to therapy in these patients. Aim To evaluate the role of HFE mutations in the severity of liver disease and in the response to therapy in chronic hepatitis C. Methods Two hundred and sixty-four hepatitis C patients treated with standard interferon and ribavirin were divided into two groups according to type of antiviral response: sustained virological response (SVR) and nonresponse or relapse. We evaluated the relationship between HFE mutation and the type of antiviral response, clinical data, biochemical tests, liver histopathology, virological data, and HFE mutations. Results Of the 264 patients, 88 (32.1%) had SVR whereas 67.9% had nonresponse or relapse. Liver iron deposits were observed in 49.2% of the patients. The factors associated with SVR were hepatitis C virus genotype 2 or 3, transferrin saturation value of 45% or less, and detection of the H63D mutation. HFE mutation was more frequent in patients with iron deposits, but without association with serum iron biochemistry or severity of liver disease. Steatosis was more frequent in patients with liver iron deposits. Conclusion The H63D mutation was an independent factor associated with SVR in chronic hepatitis C patients, as also were hepatitis C virus genotype 2 or 3 and transferrin saturation value of 45% or less. Moreover, the H63D mutation was associated with liver iron deposits. Eur J Gastroenterol Hepatol 22: 1204-1210 (C) 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins.
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Human leukocyte antigen-G (HLA-G) is a non-classical major histocompatibility complex class lb molecule that acts as a specific immunosuppressor. Some studies have demonstrated that human papillomavirus (HPV) seems to be involved in lower or absent HLA-G expression, particularly in cervical cancer. In this study, we performed a cross-sectional study, systematically comparing the qualitative expression of the HLA-G5 isoform in invasive cervical carcinoma (ICC), stratifying patients according to the presence [ICC with metastasis (ICC(W))) and absence [ICC without metastasis (ICC(WT))] of metastasis, correlating these findings with interference of HPV and demographic and clinical variables. Seventy-nine patients with a diagnosis of ICC were stratified into two groups: ICC(WT) (n=52 patients) and ICC(W) (n=27). Two biopsies were collected from each patient (one from the tumor lesion and one from a lymph node). Immunohistochemistry analyses were performed for the HLA-G5 isoform, for HPV detection, and virus typing. HLA-G5 isoform molecules were detected in 25 cases (31.6%), 17 (32.7%) without metastasis and 8 (29.6%) with metastasis. HPV was detected in the cervical lesions of 74 patients (93.7%), but low expression of the HLA-G5 isoform was observed in all HPV-related cases. These findings are important; however, additional studies are necessary to identify the influence of HPV with HLA-G5 isoform expression on invasive cervical malignancies. (J Histochem Cytochem 58:405-411, 2010)
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We report a case of acute monoblastic leukemia showing a jumping translocation with the MLL gene in a 17-year-old male. Classic cytogenetic and spectral karyotyping revealed a complex karyotype, and fluorescence in situ hybridization (FISH) demonstrated amplification of the MLL gene followed by translocation to chromosomes 15q, 17q, and 19q. In addition, molecular analyses showed a high expression of AURKA and AURKB genes. It is already known that overexpression of Aurora kinases is associated with chromosomal instability and poor prognosis. The formation of jumping translocations is a rare cytogenetic event and there is evidence pointing toward preferential involvement of the heterochromatin region of donor chromosomes and the telomere ends of recipient chromosomes. Jumping translocation with the MLL gene rearrangement is an uncommon phenomenon reported in leukemia cytogenetics. (C) 2010 Elsevier Inc. All rights reserved.
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Objective: To investigate the association of different types of magnetic resonance imaging (MRI)-detected medial meniscal pathology with subregional cartilage loss in the medial tibiofemoral compartment. Methods: A total of 152 women aged >= 40 years, with and without knee osteoarthritis (OA) were included in a longitudinal 24-month observational study. Spoiled gradient recalled acquisitions at steady state (SPGR) and T2-weighted fat-suppressed MRI sequences were acquired. Medial meniscal status of the anterior horn (AH), body, and posterior horn (PH) was graded at baseline: 0 (normal), 1 (intrasubstance meniscal signal changes), 2 (single tears), and 3 (complex tears/maceration). Cartilage segmentation was performed at baseline and 24-month follow-up in various tibiofemoral subregions using computation software. Multiple linear regression models were applied for the analysis with cartilage loss as the outcome. In a first model, the results were adjusted for age and body mass index (BMI). In a second model, the results were adjusted for age, BMI and medial meniscal extrusion. Results: After adjusting for age, BMI, and medial meniscal extrusion, cartilage loss in the total medial tibia (MT) (0.04 mm, P=0.04) and the external medial tibia (eMT) (0.068 mm, P=0.04) increased significantly for compartments with grade 3 lesions. Cartilage loss in the total central medial femoral condyle (cMF) (0.071 mm, P=0.03) also increased significantly for compartments with grade 2 lesions. Cartilage loss at the eMT was significantly related to tears of the PH (0.074 mm; P=0.03). Cartilage loss was not significantly increased for compartments with grade 1 lesions. Conclusion: The protective function of the meniscus appears to be preserved in the presence of intrasubstance meniscal signal changes. Prevalent single tears and meniscal maceration were found to be associated with increased cartilage loss in the same compartment, especially at the PH. (C) 2009 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.
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Resistant hypertension (RH) is the maintenance of elevated blood pressure concurrent with the use of three different antihypertensive drugs, one of which is a diuretic. The Renin-Angiotensin-Aldosterone System plays a major role in volume-dependent hypertension. Therefore, its components are interesting targets for genetic association studies. This work focused on the -344 C/T polymorphism in the CYP11b2 gene, which encodes aldosterone synthase. This work evaluates the association between T allele and resistance to anti-hypertensive treatment. Genotyping analysis included 88 subjects with RH, 142 who were responsive to anti-hypertensive treatment and 110 subjects as a control group. Plasmatic concentrations of aldosterone, renin and cortisol, carotid intima-media thickness and carotid-femoral pulse wave velocity were assessed in a smaller subset of hypertensive patients. An association was found between T allele and hypertension (P < 0.005), but there was no difference in allele frequencies between both hypertensive groups. There was no difference in plasmatic parameters either, in remodeling indicators between the genotypic groups.
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The cavernosal tissue is highly responsive to endothelin-1 (ET-1), and penile smooth muscle cells not only respond to but also synthesize ET-1. Considering that ET-1 is directly involved in end-organ damage in salt-sensitive forms of hypertension, we hypothesized that activation of the ET-1/ET(A) receptor pathway contributes to erectile dysfunction (ED) associated with mineralocorticoid hypertension. Wistar rats were uninephrectomized and submitted to deoxycorticosterone acetate (DOCA)-salt treatment for 5 weeks. Control (Uni [uninephrectomized control]) animals were uninephrectomized and given tap water. Uni and DOCA-salt rats were simultaneously treated with vehicle or atrasentan (ET(A) receptor antagonist, 5 mg/Kg/day). Cavernosal reactivity to ET-1, phenylephrine (PE), ET(B) receptor agonist (IRL-1620) and electric field stimulation (EFS) were evaluated in vitro. Expression of ROCK alpha, ROCK beta, myosin phosphatase target subunit 1 (MYPT-1), and extracellular signal-regulated kinase 1/2 (ERK 1/2) were evaluated by western blot analysis. ET-1 and ET(A) receptor mRNA expression was evaluated by real-time reverse-transcriptase polymerase chain reaction. Voltage-dependent increase in intracavernosal pressure/mean arterial pressure (ICP/MAP) was used to evaluate erectile function in vivo. ET(A) receptor blockade prevents DOCA-salt-associated ED. Cavernosal strips from DOCA-salt rats displayed augmented preproET-1 expression, increased contractile responses to ET-1 and decreased relaxation to IRL-1620. Contractile responses induced by EFS and PE were enhanced in cavernosal tissues from DOCA-salt hypertensive rats. These functional changes were associated with increased activation of the RhoA/Rho-kinase and ERK 1/2 pathways. Treatment of rats with atrasentan completely prevented changes in cavernosal reactivity in DOCA-salt rats and restored the decreased ICP/MAP, completely preventing ED in DOCA-salt rats. Activation of the ET-1/ET(A) pathway contributes to mineralocorticoid hypertension-associated ED. ET(A) receptor blockade may represent an alternative therapeutic approach for ED associated with salt-sensitive hypertension and in pathological conditions where increased levels of ET-1 are present. Carneiro FS, Nunes KP, Giachini FRC, Lima VV, Carneiro ZN, Nogueira EF, Leite R, Ergul A, Rainey WE, Webb RC, and Tostes RC. Activation of the ET-1/ETA pathway contributes to erectile dysfunction associated with mineralocorticoid hypertension. J Sex Med **;**:**-**.
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The strong inflammatory reaction that occurs in the heart during the acute phase of Trypanosoma cruzi infection is modulated by cytokines and chemokines produced by leukocytes and cardiomyocytes. Matrix metalloproteinases (MMPs) have recently emerged as modulators of cardiovascular inflammation. In the present study we investigated the role of MMP-2 and MMP-9 in T. cruzi-induced myocarditis, by use of immunohistochemical analysis, gelatin zymography, enzyme-linked immunosorbent assay, and real-time polymerase chain reaction to analyze the cardiac tissues of T. cruzi-infected C57BL/6 mice. Increased transcripts levels, immunoreactivity, and enzymatic activity for MMP-2 and MMP-9 were observed by day 14 after infection. Mice treated with an MMP inhibitor showed significantly decreased heart inflammation, delayed peak in parasitemia, and improved survival rates, compared with the control group. Reduced levels of cardiac tumor necrosis factor-alpha, interferon-gamma, serum nitrite, and serum nitrate were also observed in the treated group. These results suggest an important role for MMPs in the induction of T. cruzi-induced acute myocarditis.
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The antihypertensive effects of angiotensin-converting enzyme inhibitors (ACEi) are explained, at least in part, by enhanced bradykinin-dependent nitric oxide (NO) formation and decreased angiotensin II-induced oxidative stress and vasoconstriction. We examined for the first time whether treatment with enalapril increases the plasma levels of markers of NO formation and decreases oxidative stress in mild to moderate hypertensive patients. Eighteen untreated hypertensive patients were treated with enalapril 10 mg/day (n = 10) or 20 mg/day (n = 8) for 60 days. Eighteen normotensive healthy controls were followed for the same period. Venous blood samples were collected at baseline and after 30/60 days of treatment with enalapril. Plasma NOx (nitrites + nitrates) concentrations were determined by using the Griess reaction. Plasma nitrite and whole blood nitrite concentrations were determined by using an ozone-based chemiluminescence assay. Plasma thiobarbituric acid-reactive species (TBARS) and 8-isoprostane concentrations were determined by a fluorimetric method and by ELISA, respectively. Treatment with enalapril decreased blood pressure in hypertensive patients. However, we found no significant changes in plasma NOx, nitrite, whole blood nitrite, and in the levels of markers of oxidative stress in both normotensive controls and hypertensive patients treated with enalapril. Our data show that enalapril 10-20 mg/day does not affect the concentrations of relevant markers of NO formation or markers of oxidative stress in mild to moderately hypertensive subjects, despite satisfactory blood pressure control. Our findings do not rule out the possibility that ACEi may produce such effects in more severely hypertensive patients treated with higher doses of ACEi.
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Objective: The aim of our study is to investigate whether genetic polymorphisms in the endothelial nitric oxide synthase (eNOS) gene (in the promoter region T(-786)C, in exon 7 (Glu298Asp) and in intron 4 (4b/4a)) or eNOS haplotypes are associated with hypertension in obese children and adolescents. Methods: We genotyped 175 healthy (controls), 110 normotensive obese and 73 hypertensive obese children and adolescents. Genotypes were determined by Taqman allele discrimination assay and real-time PCR, and by PCR followed by fragment separation by electrophoresis. We compared the distribution of eNOS genotypes, alleles and haplotypes in the three study groups of subjects. We have also measured whole-blood nitrite concentrations. Results: The 4a4a genotype for the intron 4 polymorphism was more common in normotensive obese and hypertensive obese (P < 0.01). The AspAsp genotype for Glu298Asp polymorphism was less common in normotensive obese (P < 0.02). No significant differences were found in allele distributions for the three eNOS polymorphisms. However, the haplotype combining the C, 4b and Glu variants for the three polymorphisms was more common in hypertensive obese than in normotensive obese or control children and adolescents (odds ratio = 2.28 and 2.79, respectively; 95% confidence interval: 1.31-4.31 and 1.39-5.64, respectively; both P < 0.00625). This haplotype was not associated with significantly different nitrite concentrations (P > 0.05). Conclusions: Our findings suggest that the eNOS haplotype, C b Glu, is associated with hypertension in obese children and adolescents. Further studies examining the possible interactions of eNOS haplotypes with environmental factors and other genetic markers involved in the development of obesity and its complications are warranted. International Journal of Obesity (2011) 35, 387-392; doi:10.1038/ijo.2010.146; published online 27 July 2010
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Introduction. Diabetes mellitus (DM) is a risk factor for erectile dysfunction (ED). Although type 2 DM is responsible for 90-95% diabetes cases, type 1 DM experimental models are commonly used to study diabetes-associated ED. Aim. Goto-Kakizaki (GK) rat model is relevant to ED studies since the great majority of patients with type 2 diabetes display mild deficits in glucose-stimulated insulin secretion, insulin resistance, and hyperglycemia. We hypothesized that GK rats display ED which is associated with decreased nitric oxide (NO) bioavailability. Methods. Wistar and GK rats were used at 10 and 18 weeks of age. Changes in the ratio of intracavernosal pressure/mean arterial pressure (ICP/MAP) after electrical stimulation of cavernosal nerve were determined in vivo. Cavernosal contractility was induced by electrical field stimulation (EFS) and phenylephrine (PE). In addition, nonadrenergic-noncholinergic (NANC)- and sodium nitroprusside (SNP)-induced relaxation were determined. Cavernosal neuronal nitric oxide synthase (nNOS) and endothelial nitric oxide synthase (eNOS) mRNA and protein expression were also measured. Main Outcome Measure. GK diabetic rats display ED associated with decreased cavernosal expression of eNOS protein. Results. GK rats at 10 and 18 weeks demonstrated impaired erectile function represented by decreased ICP/MAP responses. Ten-week-old GK animals displayed increased PE responses and no changes in EFS-induced contraction. Conversely, contractile responses to EFS and PE were decreased in cavernosal tissue from GK rats at 18 weeks of age. Moreover, GK rats at 18 weeks of age displayed increased NANC-mediated relaxation, but not to SNP. In addition, ED was associated with decreased eNOS protein expression at both ages. Conclusion. Although GK rats display ED, they exhibit changes in cavernosal reactivity that would facilitate erectile responses. These results are in contrast to those described in other experimental diabetes models. This may be due to compensatory mechanisms in cavernosal tissue to overcome restricted pre-penile arterial blood supply or impaired veno-occlusive mechanisms. Carneiro FS, Giachini FRC, Carneiro ZN, Lima VV, Ergul A, Webb RC, and Tostes RC. Erectile dysfunction in young non-obese type II diabetic Goto-Kakizaki rats is associated with decreased eNOS phosphorylation at Ser1177. J Sex Med 2010;7:3620-3634.