141 resultados para Boiardo, Matteo Maria, 1440 or 41-1494.
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Background: Topical flavonoids, such as quercetin, have been shown to reduce ultraviolet (UV) irradiation-mediated skin damage. However, the mechanisms and signaling pathways involved in this protective effect are not clear. UV irradiation leads to activation of two major signaling pathways, namely nuclear factor kappa B (NF-kappa B) and activator protein-1 (AP-1) pathways. Activation of NF-kappa B pathway by UV irradiation stimulates inflammatory cytokine expression, whereas activation of AP-1 pathway by UV irradiation promotes matrix metalloproteinase (MMP) production. Both pathways contribute to UV irradiation-induced skin damage, such as photoaging and skin tumor formation. Objective: To elucidate the underlying mechanism, we examined the effect of quercetin on UV irradiation induced activation of NF-kappa B and AP-1 pathways. Methods: Primary human keratinocytes, the major skin cell type subjected to physiological solar UV irradiation, were used to study the effects of quercetin on UV irradiation-induced signal transduction pathways. Results: Quercetin decreased UV irradiation-induced NF-kappa B DNA-binding by 80%. Consequently, quercetin suppressed UV irradiation-induced expression of inflammatory cytokines IL-1 beta (similar to 60%), IL-6 (similar to 80%), IL-8 (similar to 76%) and TNF-alpha (similar to 69%). In contrast, quercetin had no effect on UV irradiation activation of three MAP kinases, ERK, JNK, or p38. Accordingly, induction of AP-1 target genes such as MMP-1 and MMP-3 by UV irradiation was not suppressed by quercetin. Conclusion: Our data indicate that the ability of quercetin to block UV irradiation-induced skin inflammation is mediated, at least in part, by its inhibitory effect on NF-kappa B activation and inflammatory cytokine production. (C) 2011 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.
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Meso-tetra-(N-methylpiridinium-4-yl)-porphyrin (TMPyP) and meso-tetra-(4-sulfonatophenyl)-porphyrin (TPPS(4)) are photosensitizing drugs (PS) used in photodynamic therapy (PDT). Based on the fact that these compounds present similar chemical structures but opposite charges at pH levels near physiological conditions, this work aims to evaluate the in vitro and in vivo influence of these electrical charges on the iontophoretic delivery of TMPyP and TPPS4, attempting to achieve maximum accumulation of PS in skin tissue. The iontophoretic transport of these drugs from a hydrophilic gel was investigated in vitro using porcine ear skin and vertical, flow-through diffusion cells. In vivo experiments using rats were also carried out, and the penetration of the PSs was analyzed by fluorescence microscopy to visualize the manner of how these compounds were distributed in the skin after a short period of iontophoresis application. In vitro, both passive and iontophoretic delivery of the positively charged TMPyP were much greater (20-fold and 67-fold, respectively) than those of the negatively charged TPPS(4). TPPS(4) iontophoresis in vivo increased the fluorescence of the skin only in the very superficial layers. On the other hand, iontophoresis of the positively charged drug expressively increased the rat epidermis and dermis fluorescence, indicating high amounts of this drug throughout the skin layers. Moreover, TMPyP was homogeneously distributed around and into the nuclei of the skin cells, suggesting its potential use in topical PDT. (C) 2010 Elsevier B.V. All rights reserved.
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Considering that antioxidant flavonols have been reported to be beneficial to human health, but that their low water solubility and bioavailability limit their administration through systemic route, the development of suitable flavonol-carriers is of great importance for clinical therapeutics. The aim of this study was to prepare liposomes containing flavonols or not and evaluate their antioxidant activity. Vesicles were obtained by ethanol injection method and characterized in terms of entrapment efficiency, size and zeta potential. Inhibitory activity of liposomal flavonols on reactive oxygen species generation was assessed in vitro using luminol--H(2)O(2)--horseradish peroxidase technique. Antioxidant activity of liposomal flavonols is dependent on concentration and chemical structure of active compound. Quercetin and myricetin are the most active flavonols (IC(50) == 0.6--0.9 mu A mu mol/L), followed by kaempferol (IC(50) == 3.0--4.5 mu A mu mol/L) and galangin (IC(50) == 4.0--7.0 mu A mu mol/L). Our results suggest that antioxidant-loaded liposomes may be promising tools for therapy of diseases where oxidative stress is involved.
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Solanum lycocarpum A. St. Hil. (Solanaceae) is a hairy shrub or small much-branched tree of the Brazilian Cerrado. S. lycocarpum fruits are commonly used in traditional medicine in powder form or as folk preparations for the treatment of diabetes and obesity, as well as for controlling cholesterol levels. The aim of the present study was to chemically characterize the hydroalcoholic extract (SL) of S. lycocarpum by determination of total flavonoids and total poyphenols and quantification of steroidal alkaloids, as well as to evaluate its mutagenic and/or antimutagenic potential on V79 cells and Swiss mice using chromosomal aberrations and bone marrow micronucleus assays, respectively. Three concentrations of SL (16, 32, and 24 mu g/mL) were used for the evaluation of its mutagenic potential in V79 cells and four doses (0.25, 0.50, 1.0, and 2.0 g/kg body weight) were used for Swiss mice. In the antimutagenicity assays, the different concentrations of SL were combined with the chemotherapeutic agent doxorubicin (DXR). HPLC analysis of SL gave contents of 6.57% +/- 0.41 of solasonine and 4.60% +/- 0.40 of solamargine. Total flavonoids and polyphenols contents in SL were 0.04 and 3.60%, respectively. The results showed that not only SL exerted no mutagenic effect, but it also significantly reduced the frequency of chromosomal aberrations induced by DXR in both V79 cells and micronuclei in Swiss mice at the doses tested.
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With a 41-society sample of 9990 managers and professionals, we used hierarchical linear modeling to investigate the impact of both macro-level and micro-level predictors on subordinate influence ethics. While we found that both macro-level and micro-level predictors contributed to the model definition, we also found global agreement for a subordinate influence ethics hierarchy. Thus our findings provide evidence that developing a global model of subordinate ethics is possible, and should be based upon multiple criteria and multilevel variables. Journal of International Business Studies (2009) 40, 1022-1045. doi:10.1057/jibs.2008.109
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The present study aimed to determine the richness, occurrence constancy, reproductive modes. standard of abundance distribution, season of vocalization and to test correlation among climatic variables and activity of vocalization of anurans in a region of the Pampa Biome, Santa Maria, Rio Grande do Sul State. During the period of Novernber/2001 to October/2002 monthly collections were carried out utilizing the `survey at breeding site` method and examination of specimens kept in the Colecao Herpetologica do Setor de Zoologia da Universidade Federal de Santa Maria (ZUFSM). Tire Occurrence of 25 species of anurans was recorded. The anurofauna recorded represents 30% of the species known to Occur in Rio Grande do Sul, and comprises species generally associated with grasslands in this state and neighboring countries. Four reproductive modes were recorded: mode 1 (14 species: 58.3%) mode 11 and 30 (9 species` 37.5%) and mode 24 (1 species; 4.2%). The low diversification of reproductive modes is likely related to the homogeneity of the grassland habitat. Most species were constant or accessory in the Study area and the species abundance distribution patterns fit in the Broken Stick and Log-normal models. characterized by homogeneity of species abundance distribution. Most species showed great plasticity in habitat. but few were plastic in vocalization sites use. There was a weak positive correlation between species richness and precipitation. There was also a weak positive correlation between the abundance of species calling activity and maximum average temperatures. These correlations indicated that, in the study area. the abundance of calling males is more affected by the temperature, and species richness is more affected by precipitation, despite the fact that significantly higher species richness occurs during the hottest period of the year. These results showed that the climatological variables examined were not enough to explain the seasonal occurrence of species, thus the influence of other environmental variables merit to be tested in future studies.
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Although a new protocol of dobutamine stress echocardiography with the early injection of atropine (EA-DSE) has been demonstrated to be useful in reducing adverse effects and increasing the number of effective tests and to have similar accuracy for detecting coronary artery disease (CAD) compared with conventional protocols, no data exist regarding its ability to predict long-term events. The aim of this study was to determine the prognostic value of EA-DSE and the effects of the long-term use of beta blockers on it. A retrospective evaluation of 844 patients who underwent EA-DSE for known or suspected CAD was performed; 309 (37%) were receiving beta blockers. During a median follow-up period of 24 months, 102 events (12%) occurred. On univariate analysis, predictors of events were the ejection fraction (p <0.001), male gender (p <0.001), previous myocardial infarction (p <0.001), angiotensin-converting enzyme inhibitor therapy (p = 0.021), calcium channel blocker therapy (p = 0.034), and abnormal results on EA-DSE (p <0.001). On multivariate analysis, the independent predictors of events were male gender (relative risk [RR] 1.78, 95% confidence interval [CI] 1.13 to 2.81, p = 0.013) and abnormal results on EA-DSE (RR 4.45, 95% CI 2.84 to 7.01, p <0.0001). Normal results on EA-DSE with P blockers were associated with a nonsignificant higher incidence of events than normal results on EA-DSE without beta blockers (RR 1.29, 95% CI 0.58 to 2.87, p = 0.54). Abnormal results on EA-DSE with beta blockers had an RR of 4.97 (95% CI 2.79 to 8.87, p <0.001) compared with normal results, while abnormal results on EA-DSE without beta blockers had an RR of 5.96 (95% CI 3.41 to 10.44, p <0.001) for events, with no difference between groups (p = 0.36). In conclusion, the detection of fixed or inducible wall motion abnormalities during EA-DSE was an independent predictor of long-term events in patients with known or suspected CAD. The prognostic value of EA-DSE was not affected by the long-term use of beta blockers. (C) 2008 Elsevier Inc. All rights reserved. (Am J Cardiol 2008;102:1291-1295)
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Non-syndromic cleft lip with or without cleft palate (NS CL/P) is a complex disease in which heritability estimates vary widely depending on the population studied. To evaluate the importance of genetic contribution to NS CL/P in the Brazilian population, we conducted a study with 1,042 families from five different locations (Santarem, Fortaleza, Barbalha, Maceio, and Rio de Janeiro). We also evaluated the role of consanguinity and ethnic background. The proportion of familial cases varied significantly across locations, with the highest values found in Santarem (44%) and the lowest in Maceio (23%). Heritability estimates showed a higher genetic contribution to NS CL/P in Barbalha (85%), followed by Santarem (71%), Rio de Janeiro (70%), Fortaleza (64%), and Maceio (45%). Ancestry was not correlated with the occurrence of NS CL/P or with the variability in heritability. Only in Rio de Janeiro was the coefficient of inbreeding significantly larger in NS CL/P families than in the local population. Recurrence risk for the total sample was approximately 1.5-1.6%, varying according to the location studied (0.6-0.7% in Maceio to 2.2-2.8% in Barbalha). Our findings show that the degree of genetic contribution to NS CL/P varies according to the geographic region studied, and this difference cannot be attributed to consanguinity or ancestry. These findings suggest that Barbalha is a promising region for genetic studies. The data presented here will be useful in interpreting results from molecular analyses and show that care must be taken when pooling samples from different populations for association studies. (C) 2011 Wiley-Liss, Inc.
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A number of studies conducted in humans and in animals have observed that events occurring early in life are associated with the development of diseases in adulthood. Salt overload and restriction during pregnancy and lactation are responsible for functional (hemodynamic and hormonal) and structural alterations in adult offspring. Our group observed that lower birth weight and insulin resistance in adulthood is associated with salt restriction during pregnancy On the other hand, perinatal salt overload is associated with higher blood pressure and higher renal angiotensin II content in adult offspring. Therefore, we hypothesised that renin-angiotensin system (RAS) function is altered by changes in sodium intake during pregnancy. Such changes may influence fetoplacental blood flow and thereby fetal nutrient supply, with effects on growth in utero and, consequently, on birth weight. Female Wistar rats were fed low-salt (LS), normal-salt (NS), or high-salt (HS) diet, starting before conception and continuing until day 19 of pregnancy, Blood pressure, heart rate, fetuses and dams` body weight, placentae weight and litter size were measured on day 19 of pregnancy. Cardiac output, uterine and placental blood flow were also determined on day 19. Expressions of renin-angiotensin system components and of the TNF-alpha gene were evaluated in the placentae. Plasma renin activity (PRA) and plasma and tissue angiotensin-converting enzyme (ACE) activity, as well as plasma and placental levels of angiotensins I, II, and 1-7 were measured. Body weight and kidney mass were greater in HS than in NS and LS dams. Food intake did not differ among the maternal groups. Placental weight was lower in LS dams than in NS and HS dams. Fetal weight was lower in the US group than in the NS and HS groups. The PRA was greater in IS dams than in NS and HS dams, although ACE activity (serum, cardiac, renal, and placental) was unaffected by the level of sodium intake. Placental levels of angiotensins I and II were lower in the HS group than in the ISIS and IS groups. Placental angiotensin receptor type 1 (AT(1)) gene expression and levels of thiobarbituric acid reactive substances (TBARS) were higher in HS dams, as were uterine blood flow and cardiac output. The degree of salt intake did not influence plasma sodium, potassium or creatinine. Although fractional sodium excretion was higher in HS dams than in NS and LS dams, fractional potassium excretion was unchanged. In conclusion, findings from this study indicate that the reduction in fetal weight in response to salt restriction during pregnancy does not involve alterations in uterine-placental perfusion or the RAS. Moreover, no change in fetal weight is observed in response to salt overload during pregnancy. However, salt overload did lead to an increase in placental weight and uterine blood flow associated with alterations in maternal plasma and placental RAS. Therefore, these findings indicate that changes in salt intake during pregnancy lead to alterations in uterine-placental perfusion and fetal growth. (C) 2008 Elsevier Inc. All rights reserved.
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Objectives: To evaluate the effects of Metformin and Glyburide on cardiovascular, metabolic and hormonal parameters during progressive exercise performed to exhaustion in the post-prandial state in women with type 2 diabetes (T2DM). Design and Methods: Ten T2DM patients treated with Metformin (M group), 10 with Glyburide (G group) and 10 age-paired healthy subjects exercised on a bicycle ergometer up to exercise peak. Cardiovascular and blood metabolic and hormonal parameters were measured at times -60 min, 0 min, exercise end, and at 10 and 20 minutes of recovery phase. Thirty minutes before the exercise, a standard breakfast was provided to all participants. The diabetic patients took Metformin or Glyburide before or with meal. Results: Peak oxygen uptake (VO2) was lower in patients with diabetes. Plasma glucose levels remained unchanged, but were higher in both diabetic groups. Patients with diabetes also presented lower insulin levels after meals and higher glucagon levels at exercise peak than C group. Serum cortisol levels were higher in G than M group at exercise end and recovery phase. Lactate levels were higher in M than G group at fasting and in C group at exercise peak. Nor epinephrine, GH and FFA responses were similar in all 3 groups. Conclusion: Progressive exercise performed to exhaustion, in the post-prandial state did not worsen glucose control during and after exercise. The administration of the usual dose of Glyburide or Metformin to T2DM patients did not influence the cardiovascular, metabolic and hormonal response to exercise.
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To identify the underlying mechanism of amenorrhea in juvenile systemic lupus erythematosus (JSLE) patients, thirty-five (11.7%) JSLE patients with current or previous amenorrhea were consecutively selected among the 298 post-menarche patients followed in 12 Brazilian pediatric rheumatology centers. Pituitary gonadotrophins [follicle-stimulating hormone (FSH) and luteinizing hormone (LH)] and estradiol were evaluated in 32/35 patients, and prolactin and total testosterone in 29/35 patients. Patient`s medical records were carefully reviewed according to demographic, clinical and therapeutic findings. The mean duration of amenorrhea was 7.2 +/- A 3.6 months. Low FSH or LH was observed in 7/32 (22%) JSLE patients and normal FSH or LH in 25 (78%). Remarkably, low levels of FSH or LH were associated with higher frequency of current amenorrhea (57% vs. 0%, P = 0.001), higher median disease activity (SLEDAI) and damage (SLICC/ACR-DI) (18 vs. 4, P = 0.011; 2 vs. 0, P = 0.037, respectively) and higher median current dose of prednisone (60 vs. 10 mg/day, P = 0.0001) compared to normal FSH or LH JSLE patients. None of them had decreased ovarian reserve and premature ovarian failure. Six of 29 (21%) patients had high levels of prolactin, and none had current amenorrhea. No correlations were observed between levels of prolactin and SLEDAI, and levels of prolactin and SLICC/ACR-DI scores (Spearman`s coefficient). We have identified that amenorrhea in JSLE is associated with high dose of corticosteroids indicated for active disease due to hypothalamic-pituitary-ovary axis suppression.
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Background-This study compared the 10-year follow-up of percutaneous coronary intervention (PCI), coronary artery surgery (CABG), and medical treatment (MT) in patients with multivessel coronary artery disease, stable angina, and preserved ventricular function. Methods and Results-The primary end points were overall mortality, Q-wave myocardial infarction, or refractory angina that required revascularization. All data were analyzed according to the intention-to-treat principle. At a single institution, 611 patients were randomly assigned to CABG (n = 203), PCI (n = 205), or MT (n = 203). The 10-year survival rates were 74.9% with CABG, 75.1% with PCI, and 69% with MT (P = 0.089). The 10-year rates of myocardial infarction were 10.3% with CABG, 13.3% with PCI, and 20.7% with MT (P < 0.010). The 10-year rates of additional revascularizations were 7.4% with CABG, 41.9% with PCI, and 39.4% with MT (P < 0.001). Relative to the composite end point, Cox regression analysis showed a higher incidence of primary events in MT than in CABG (hazard ratio 2.35, 95% confidence interval 1.78 to 3.11) and in PCI than in CABG (hazard ratio 1.85, 95% confidence interval 1.39 to 2.47). Furthermore, 10-year rates of freedom from angina were 64% with CABG, 59% with PCI, and 43% with MT (P < 0.001). Conclusions-Compared with CABG, MT was associated with a significantly higher incidence of subsequent myocardial infarction, a higher rate of additional revascularization, a higher incidence of cardiac death, and consequently a 2.29-fold increased risk of combined events. PCI was associated with an increased need for further revascularization, a higher incidence of myocardial infarction, and a 1.46-fold increased risk of combined events compared with CABG. Additionally, CABG was better than MT at eliminating anginal symptoms.
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Dias RG, Alves MJ, Pereira AC, Rondon MU, dos Santos MR, Krieger JE, Krieger MH, Negrao CE. Glu298Asp eNOS gene polymorphism causes attenuation in nonexercising muscle vasodilatation. Physiol Genomics 37: 99-107, 2009. First published January 21, 2009; doi:10.1152/physiolgenomics.90368.2008.-The influence of Glu298Asp endothelial nitric oxide synthase (eNOS) polymorphism in exercise-induced reflex muscle vasodilatation is unknown. We hypothesized that nonexercising forearm blood flow (FBF) responses during handgrip isometric exercise would be attenuated in individuals carrying the Asp298 allele. In addition, these responses would be mediated by reduced eNOS function and NO-mediated vasodilatation or sympathetic vasoconstriction. From 287 volunteers previously genotyped, we selected 33 healthy individuals to represent three genotypes: Glu/Glu [n = 15, age 43 +/- 3 yr, body mass index (BMI) 22.9 +/- 0.3 kg/m(2)], Glu/Asp (n = 9, age 41 +/- 3 yr, BMI 23.7 +/- 1.0 kg/m(2)), and Asp/Asp (n = 9, age 40 +/- 4 yr, BMI 23.5 +/- 0.9 kg/m(2)). Heart rate (HR), mean blood pressure (MBP), and FBF (plethysmography) were recorded for 3 min at baseline and 3 min during isometric handgrip exercise. Baseline HR, MBP, FBF, and forearm vascular conductance (FVC) were similar among genotypes. FVC responses to exercise were significantly lower in Asp/Asp when compared with Glu/Asp and Glu/Glu (Delta = 0.07 +/- 0.14 vs. 0.64 +/- 0.20 and 0.57 +/- 0.09 units, respectively; P = 0.002). Further studies showed that intra-arterial infusion of N(G)-monomethyl-L-arginine (L-NMMA) did not change FVC responses to exercise in Asp/Asp, but significantly reduced FVC in Glu/Glu (Delta = 0.79 +/- 0.14 vs. 0.14 +/- 0.09 units). Thus the differences between Glu/Glu and Asp/Asp were no longer observed (P = 0.62). L-NMMA + phentolamine increased similarly FVC responses to exercise in Glu/Glu and Asp/Asp (P = 0.43). MBP and muscle sympathetic nerve activity increased significant and similarly throughout experimental protocols in Glu/Glu and Asp/Asp. Individuals who are homozygous for the Asp298 allele of the eNOS enzyme have attenuated nonexercising muscle vasodilatation in response to exercise. This genotype difference is due to reduced eNOS function and NO-mediated vasodilatation, but not sympathetic vasoconstriction.
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Pattern recognition methods have been successfully applied in several functional neuroimaging studies. These methods can be used to infer cognitive states, so-called brain decoding. Using such approaches, it is possible to predict the mental state of a subject or a stimulus class by analyzing the spatial distribution of neural responses. In addition it is possible to identify the regions of the brain containing the information that underlies the classification. The Support Vector Machine (SVM) is one of the most popular methods used to carry out this type of analysis. The aim of the current study is the evaluation of SVM and Maximum uncertainty Linear Discrimination Analysis (MLDA) in extracting the voxels containing discriminative information for the prediction of mental states. The comparison has been carried out using fMRI data from 41 healthy control subjects who participated in two experiments, one involving visual-auditory stimulation and the other based on bimanual fingertapping sequences. The results suggest that MLDA uses significantly more voxels containing discriminative information (related to different experimental conditions) to classify the data. On the other hand, SVM is more parsimonious and uses less voxels to achieve similar classification accuracies. In conclusion, MLDA is mostly focused on extracting all discriminative information available, while SVM extracts the information which is sufficient for classification. (C) 2009 Elsevier Inc. All rights reserved.
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Background. The am of this study was to determine the predictive value for malignancy of microcalcifications determined by ultrasonography in thyroid nodules. Methods. One hundred seventy-seven nodules were prospectively studied by ultrasonography and compared with their fine-needle aspirative biopsy. The association between the presence and type of calcification and cytologic findings was verified through the chi-square test or likelihood ratio. Results. Thirty nodules showed calcification, of which 17 had fine calcifications, 3 had fine and gross calcifications, and 10 had only coarse calcification. Seven (41.18%) of 17 fine calcified nodules were malignant on cytology, 8 (47.06%) were benign, 1 (5,88%) was indeterminate, and 1 was suspect for malignancy. We found statistical significance between the presence of fine calcifications and malignancy (p =.001) and, in the 13 malignant nodule group, 8 (61.50%) had fine calcifications. Conclusion. This study suggests that microcalcifications were highly specific for malignancy and were present in 61% of the malignant nodules. (c) 2008 Wiley Periodicals, Inc.