211 resultados para Renal vascular conductance


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Introduction. Advantages of the bicaval versus the biatrial technique have been reported, emphasizing atrial electrical stability and less tricuspid regurgitation. Objective. To analyze the impact of the surgical technique on long-term pulmonary pressures, contractility, and graft valvular behavior after heart transplantation. Methods. Among 400 orthotopic heart transplantation recipients from 1985 to 2010, we selected 30 consecutive patients who had survived beyond 3 years. The biatrial versus bicaval surgical technique groups included 15 patients each. Their preoperative clinical characteristics were similar. None of the patients displayed a pulmonary vascular resistance or pulmonary artery pressure over 6U Wood or 60 mm Hg, respectively. We evaluated invasive hemodynamic parameters during routine endomyocardial biopsies. Two-dimensional echocardiographic parameters were obtained from routine examinations. Results. There were no significant differences regarding right atrial pressure, systolic pulmonary artery pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance, cardiac index, systolic blood pressure, left ventricular ejection fraction, and mitral regurgitation (P > .05). Tricuspid regurgitation increased significantly over the 3 years of observation only among the biatrial group (P = .0212). In both groups, the right atrial pressure, pulmonary wedge capillary pressure, transpulmonary gradient, and pulmonary vascular resistance decreased significantly (P < .05) from the pre- to the postoperative examination. In both groups cardiac index and systemic blood pressure increased significantly after transplantation (P < .05). Comparative analysis of the groups only showed significant differences regarding right atrial pressure and degree of tricuspid regurgitation; the bicaval group showing the best performance. Conclusions. Both surgical techniques ensure adequate left ventricular function in the long term; however, the bicaval technique provided better trends in hemodynamic performance, as well as a lower incidence and severity of tricuspid valve dysfunction.

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In this study, we analyzed whether transplantation of cardiac fibroblasts (CFs) expressing vascular endothelial growth factor (VEGF) mitigates cardiac dysfunction after myocardial infarction (MI) in rats. First, we observed that the transgene expression lasts longer (45 vs 7 days) when fibroblasts are used as vectors compared with myoblasts. In a preventive protocol, induction of cardiac neovascularization accompanied by reduction in myocardial scar area was observed when cell transplantation was performed 1 week before ischemia/reperfusion and the animals analyzed 3 weeks later. Finally, the therapeutic efficacy of this approach was tested injecting cells in a fibrin biopolymer, to increase cardiac retention, 24 h post-MI. After 4 weeks, an increase in neovascularization and a decrease in myocardial collagen were observed only in rats that received cells expressing VEGF. Basal indirect or direct hemodynamic measurements showed no differences among the groups whereas under pharmacological stress, only the group that received cells expressing VEGF showed a significant reduction in end-diastolic pressure and improvement in stroke volume and cardiac work. These results indicate that transplantation of CFs expressing VEGF using fibrin biopolymer induces neovascularization and attenuates left ventricle fibrosis and cardiac dysfunction in ischemic heart. Gene Therapy (2010) 17, 305-314; doi:10.1038/gt.2009.146; published online 10 December 2009

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Background Metastatic renal cell carcinoma (mRCC) is one of the most treatment-resistant malignancies. Despite all new therapeutic advances, almost all patients develop resistance to treatment and cure is rarely seen. In the present study, we evaluated the antitumor effect of a bicistronic retrovirus vector encoding both endostatin (ES) and interleukin (IL)-2 using an orthotopic metastatic RCC mouse model. Methods Balb/C-bearing Renca cells were treated with NIH/3T3-LendIRES-IL-2-SN cells. In the survival studies, mice were monitored daily until they died. At the end of the in vivo experiment, serum levels of IL-2 and ES were measured, the lung was weighed, and the number of metastatic nodules, nodule area, tumor vessels and proliferation of tumor-infiltrating Renca cells were determined. Results Inoculation of NIH/3T3-LendIRES-IL-2-SN cells resulted in an increase in ES and IL-2 levels in the treated group (p < 0.05). There was a significant decrease in lung wet weight, lung nodule area and tumor vessels in the treated group compared to the control group (p < 0.001). The proliferation of Renca cells in the bicistronic-treated group was significantly reduced compared to the control group (p < 0.05). Kaplan-Meier survival curves showed that the probability of survival was significantly higher for mice submitted to bicistronic therapy (log-rank test, p = 0.0016). Bicistronic therapy caused an increase in the infiltration of CD4, CD4 interferon (IFN)gamma-producing, CD8, CD8 IFN gamma-producing and natural killer (CD49b) cells. Conclusions Retroviral bicistronic gene transfer led to the secretion of functional ES and IL-2 that was sufficiently active to: (i) inhibit tumor angiogenesis and tumor cell proliferation and (ii) increase the infiltration of immune cells (C) Copyright. 2011 John Wiley & Sons, Ltd.

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We investigated whether the administration of IL-2 combined with endostatin gene therapy was able to produce additive or even synergistic immunomodulatory activity in a mouse model of metastatic renal carcinoma. Renca cells were injected into the tail vein of BALB/c mice. After 24 h, the animals were randomly divided into four groups (5 mice/group). One group of mice was the control, the second group received treatment with 100,000 UI of Recombinant IL-2 (Proleukin, Chiron) twice a day, 1 day per week during 2 weeks (IL-2), the third group received treatment with a subcutaneous inoculation of 3.6 x 10(6) endostatin-producing cells, and the fourth group received both therapies (IL-2 + ES). Mice were treated for 2 weeks. In the survival studies, 10 mice/group daily, mice were monitored daily until they died. The presence of metastases led to a twofold increase in endostatin levels. Subcutaneous inoculation of NIH/3T3-LendSN cells resulted in a 2.75 and 2.78-fold increase in endostatin levels in the ES and IL-2 + ES group, respectively. At the end of the study, there was a significant decrease in lung wet weight, lung nodules area, and microvascular area (MVA) in all treated groups compared with the control group (P < 0.001). The significant difference in lung wet weight and lung nodules area between groups IL-2 and IL-2 + ES revealed a synergistic antitumor effect of the combined treatment (P < 0.05). The IL-2 + ES therapy Kaplan-Meier survival curves showed that the probability of survival was significantly higher for mice treated with the combined therapy (log-rank test, P = 0.0028). Conjugated therapy caused an increase in the infiltration of CD4, CD8 and CD49b lymphocytes. An increase in the amount of CD8 cells (P < 0.01) was observed when animals received both ES and IL-2, suggesting an additive effect of ES over IL-2 treatment. A synergistic effect of ES on the infiltration of CD4 (P < 0.001) and CD49b cells (P < 0.01) was also observed over the effect of IL-2. Here, we show that ES led to an increase in CD4 T helper cells as well as cytotoxic lymphocytes, such as NK cells and CD8 cells, within tumors of IL-2 treated mice. This means that ES plays a role in supporting the actions of T cells.

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The histopathological counterpart of white matter hyperintensities is a matter of debate. Methodological and ethical limitations have prevented this question to be elucidated. We want to introduce a protocol applying state-of-the-art methods in order to solve fundamental questions regarding the neuroimaging-neuropathological uncertainties comprising the most common white matter hyperintensities [WMHs] seen in aging. By this protocol, the correlation between signal features in in situ, post mortem MRI-derived methods, including DTI and MTR and quantitative and qualitative histopathology can be investigated. We are mainly interested in determining the precise neuroanatomical substrate of incipient WMHs. A major issue in this protocol is the exact co-registration of small lesion in a tridimensional coordinate system that compensates tissue deformations after histological processing. The protocol is based on four principles: post mortem MRI in situ performed in a short post mortem interval, minimal brain deformation during processing, thick serial histological sections and computer-assisted 3D reconstruction of the histological sections. This protocol will greatly facilitate a systematic study of the location, pathogenesis, clinical impact, prognosis and prevention of WMHs. (C) 2009 Elsevier B.V. All rights reserved.

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OBJECTIVE. The objective of our study was to describe the T1 and T2 signal intensity characteristics of papillary renal cell carcinoma (RCC) and clear cell RCC with pathologic correlation. MATERIALS AND METHODS. Of 539 RCCs, 49 tumors (21 papillary RCCs and 28 clear cell RCCs) in 45 patients were examined with MRI. Two radiologists retrospectively and independently assessed each tumor`s T1 and T2 signal intensity qualitatively and quantitatively (i.e., the signal intensity [SI] ratio [tumor SI/renal cortex SI]). Of the 49 tumors, 37 (76%) were assessed for pathology features including tumor architecture and the presence of hemosiderin, ferritin, necrosis, and fibrosis. MRI findings and pathology features were correlated. Statistical methods included summary statistics and Wilcoxon`s rank sum test for signal intensity, contingency tables for assessing reader agreement, concordance rate between the two readers with 95% CIs, and Fisher`s exact test for independence, all stratified by RCC type. RESULTS. Papillary RCCs and clear cell RCCs had a similar appearance and signal intensity ratio on T1-weighted images. On T2-weighted images, most papillary RCCs were hypointense (reader 1, 13/21; reader 2, 14/21), with an average mean signal intensity ratio for both readers of 0.67 +/- 0.2, and none was hyperintense, whereas most clear cell RCCs were hyperintense (reader 1, 21/28; reader 2, 17/28), with an average mean signal intensity ratio for both readers of 1.41 +/- 0.4 (p < 0.05). A tumor T2 signal intensity ratio of <= 0.66 had a specificity of 100% and sensitivity of 54% for papillary RCC. Most T2 hypointense tumors exhibited predominant papillary architecture; most T2 hyperintense tumors had a predominant nested architecture (p < 0.05). CONCLUSION. On T2-weighted images, most papillary RCCs are hypointense and clear cell RCCs, hyperintense. The T2 hypointense appearance of papillary RCCs correlated with a predominant papillary architecture at pathology.

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Plasma clearance of (51)Cr-EDTA ((51)Cr-EDTA-Cl) is an alternative method to evaluate glomerular filtration rate (GFR). This study aimed to investigate the concordance between (51)Cr-EDTA-Cl and renal inulin clearance (In-Cl) in renal transplant recipients as well to determine the repeatability of (51)Cr-EDTA-Cl in kidney donors. Forty four kidney recipients and 22 kidney donors were enrolled. Simultaneous measurements of (51)Cr-EDTA-Cl and In-Cl were performed. A single dose of 3.7MBq of (51)Cr-EDTA was injected and the plasma disappearance curve was created by taking blood samples at 2, 4, 6 and 8 h after injection. Bland and Altman statistical approach was used to quantify the agreement between In-Cl and (51)Cr-EDTA-Cl and to determine the better concordance between all possibilities of measure for the (51)Cr-EDTA-Cl. The mean of In-Cl was 44.5 +/- 17.9 ml/min/1.73 m(2). There was a positive correlation between In-Cl and all possible measurements of (51)Cr-EDTA-Cl. (51)Cr-EDTA-Cl with two samples taken at 4 and 8 h or at 4 and 6 h presenting the narrow limits of agreement and a difference (bias) of 2.8 and 2.7 ml/min, respectively. Two plasma sampling for (51)Cr-EDTA-Cl was a reliable method to measure GFR compared with In-Cl and comprises a suitable method to be used in kidney transplanted patients.

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We aimed to investigate the vascular effects of hyperhomocysteinemia (HHcy) on carotid arteries from young and adult rats. With this purpose young and adult rats received a solution of DL-homocysteine-thiolactone (1 g/kg body weight/day) in the drinking water for 7, 14 and 28 days. Increase on plasma homocysteine occurred in young and adult rats treated with DL-homocysteine-thiolactone in all periods. Vascular reactivity experiments using standard muscle bath procedures showed that HHcy enhanced the contractile response of endothelium-intact, carotid rings to phenylephrine in both young and adult rats. However, in young rats, the increased phenylephrine-induced contraction was observed after hyperhomocysteinemia for 14 and 28 days, whereas in adult rats this response was already apparent after 7 day treatment. HHcy impaired acetylcholine-induced relaxation in arteries from adult but not young rats. The contraction induced by phenylephrine in carotid arteries in the presence of Y-27632 was reversed to control values in arteries from young but not adult rats with hyperhomocysteinemia. HHcy did not alter the contraction induced by CaCl(2) in carotid arteries from young rats, but enhanced CaCl(2)-induced contraction in the arteries from adult rats. HHcy increased the basal levels of superoxide anion in arteries from both groups. Finally, HHcy decreased the basal levels of nitrite in arteries from adult but not young rats. The major new finding of the present work is that arteries from young rats are more resistant to vascular changes evoked by HHcy than arteries from adult rats. Also, we verified that the enhanced vascular response to phenylephrine observed in carotid arteries of DL-homocysteine thiolactone-treated rats is mediated by different mechanisms in young and adult rats. (C) 2010 Published by Elsevier Inc.

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Vieira RP, de Andrade VF, Duarte AC, dos Santos AB, Mauad T, Martins MA, Dolhnikoff M, Carvalho CR. Aerobic conditioning and allergic pulmonary inflammation in mice. II. Effects on lung vascular and parenchymal inflammation and remodeling. Am J Physiol Lung Cell Mol Physiol 295: L670-L679, 2008. First published August 29, 2008; doi: 10.1152/ajplung.00465.2007.-Recent evidence suggests that asthma leads to inflammation and remodeling not only in the airways but also in pulmonary vessels and parenchyma. In addition, some studies demonstrated that aerobic training decreases chronic allergic inflammation in the airways; however, its effects on the pulmonary vessels and parenchyma have not been previously evaluated. Our objective was to test the hypothesis that aerobic conditioning reduces inflammation and remodeling in pulmonary vessels and parenchyma in a model of chronic allergic lung inflammation. Balb/c mice were sensitized at days 0, 14, 28, and 42 and challenged with ovalbumin ( OVA) from day 21 to day 50. Aerobic training started on day 21 and continued until day 50. Pulmonary vessel and parenchyma inflammation and remodeling were evaluated by quantitative analysis of eosinophils and mononuclear cells and by collagen and elastin contents and smooth muscle thickness. Immunohistochemistry was performed to quantify the density of positive cells to interleukin (IL)-2, IL-4, IL-5, interferon-gamma, IL-10, monocyte chemotatic protein (MCP)-1, nuclear factor (NF)-kappa B p65, and insulin-like growth factor (IGF)-I. OVA exposure induced pulmonary blood vessels and parenchyma inflammation as well as increased expression of IL-4, IL-5, MCP-1, NF-kappa B p65, and IGF-I by inflammatory cells were reduced by aerobic conditioning. OVA exposure also induced an increase in smooth muscle thickness and elastic and collagen contents in pulmonary vessels, which were reduced by aerobic conditioning. Aerobic conditioning increased the expression of IL-10 in sensitized mice. We conclude that aerobic conditioning decreases pulmonary vascular and parenchymal inflammation and remodeling in this experimental model of chronic allergic lung inflammation in mice.

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We compared 41 patients who received colistimethate with 41 who received polymyxin B for the treatment of serious infections caused by carbapenem-resistant Acinetobacter spp. and found both polymyxins have similar efficacy and toxicity. (C) 2009 Elsevier Inc. All rights reserved.

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Hypercalcaemia in patients with HIV infection is usually associated with specific conditions such as lymphoma and granulomatous diseases. We described a case of severe hypercalcaemia consequent to vitamin D intoxication and secondary renal failure in a HIV patient under tenofovir using. Serum creatinine and calcium returned to near normal levels after vitamin D discontinuation, saline and furosemide administration. Some aspects of the drug-induced nephropathy are discussed.

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Juvenile nasopharingeal angiofibroma (JNA) is a histologically benign locally aggressive tumor characterized by irregular vessels embedded. in a fibrous stroma. Excessive vascularity results in bleeding complications, and the inhibition of angiogenesis is a promising strategy for managing extensive JNA tumors. To better characterize the endothelial components of JNA, we aimed to evaluate markers of vascular differentiation and proliferation, such as friend leukemia integration-1 (FLI-1) and endoglin, lymphatic markers, including podoplanin and vascular endothelial growth factor receptor 3 (VEGFR3) and its cognate ligand VEGFC, GLUT-1, a diagnostic marker that discriminates between hemangiomas and vascular malformations, and two markers of tissue remodeling, stromelysin 3 (ST3) and secreted acid protein rich in cysteine (SPARC). Antigens were assessed immunohistochemically in vessels and stromal cells of JNA archival cases (n=22). JNA endothelial cells were positive for endoglin, VEGFC and FLI-1, whereas podoplanin and VEGFR3 were negative in all cases. Both endothelial cells and fibroblasts stained for ST3 and SPARC. GLUT-1 was investigated in JNA cases, in infantile hemangiomas (n=123) and in vascular malformations (n=135) as controls. JNAs and vascular malformations were GLUT-1-negative, while hemangiomas showed positive staining. The presence of markers of endothelial differentiation and proliferation highlighted the hyper-proliferative state of JNA vessels. The absence of podoplanin and VEGFR3 underscores their blood endothelial cell characteristic. The absence of GLUT-1 discriminates JNAs from hemangiomas. ST3 and SPARC up-regulation in endothelial cells and fibroblasts may contribute to a compensatory signaling for controlling angiogenesis. Some of these markers may eventually serve as therapeutic targets. Our results may aid in the understanding of JNA pathophysiology.

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Objective: To assess the association between the depth of trophoblastic penetration into the tubal wall with serum concentrations of vascular endothelial growth factor (VEGF) and beta-hCG and to assess its predictive value. Design: Prospective study. Setting: Tertiary care university hospital. Patient(s): Thirty patients with ampullary pregnancy undergoing salpingectomy were analyzed. Intervention(s): Trophoblastic invasion was histologically classified as stage I when limited to the tubal mucosa, stage II when extending to the muscle layer, and stage III in the case of complete tubal wall infiltration. Main Outcome Measure(s): The relation between depth of trophoblastic infiltration into the tubal wall with VEGF and beta-hCG serum concentrations on the day of surgery. Result(s): An association between the depth of trophoblastic invasion and maternal serum concentrations of VEGF and beta-hCG was observed. VEGF levels of 297.2 pg/mL showed 100.0% sensitivity and 90.0% specificity for stage I, and levels of 440.1 pg/mL showed 81.8% sensitivity and 88.8% specificity for stage III. Beta-hCG levels of 2590.0 mIU/mL showed 88.9% sensitivity and 80.0% specificity for stage I, and levels of 10,827.0 mUI/mL showed 72.7% sensitivity and 88.9% specificity for stage III. Conclusion(s): Maternal serum VEGF and beta-hCG concentrations are associated with depth of trophoblastic penetration into the tubal wall. (Fertil Steril (R) 2010;94:1595-600. (C) 2010 by American Society for Reproductive Medicine.)

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Objective: To analyze vascular density and immunolocalization of angiogenic vascular endothelial growth factor (VEGF) and its receptor Flk-1 in the proliferative and secretory eutopic human endometrium. and in three different sites of endometriosis: the ovary, bladder, and rectum. Design: Prospective study. Setting: University hospital. Patient(s): Thirty women with endometriosis (10 ovarian, 1.0 bladder, 10 rectal) and 32 control women (10 proliferative endometrium, 10 secretory endometrium, 4 normal ovary, 4 normal bladder, 4 normal rectum). Intervention(s): Normal endometrial samples were obtained from women during laparoscopic ablation of subserous myoma, and biopsy specimens of endometriosis were obtained from patients undergoing surgery for the diagnosis and treatment of endometriosis. Normal tissues of ovary, bladder, and rectum were obtained from these organs beside the lesions of endometriosis. Main Outcome Measure(S): Blood vessels were quantified according to the number of von Willebrand factor-positive endothelial cells. The VEGF and Flk-1 distribution were evaluated semiquantitatively by immunohistochemical staining. Result(s): More blood vessels were found in cases of endometriosis, particularly rectal endometriosis, compared with the respective control samples and with the eutopic endometrium, and they were localized in endometrial stroma around the glands. The VEGF and Flk-1 expression levels were also higher in cases of endometriosis, especially rectal endometriosis. Conclusion(s): Vascularization and VEGF and Flk-1 expression are significantly higher in deeply infiltrating endometriosis affecting the rectum, reinforcing the hypothesis that antiangiogenesis therapy may constitute a new modality of treatment, especially in cases of deep endometriosis involving the rectum.

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Purpose of review To review neuroimaging findings that have been reported in samples of patients with cardiovascular disorders and their association with the onset of Alzheimer`s disease, vascular dementia, depression and bipolar disorder in the elderly and to highlight the implications of these findings to the knowledge about the pathophysiology of psychiatric disorders in old age, as well as their potential clinical implications. Recent findings Vascular risk factors, such as hypertension, diabetes, dyslipidemia, smoking habits and heart failure, have all been associated with signs of cerebrovascular dysfunction, including structural MRI findings of signal hyperintensities, lacunes and stroke and functional imaging findings of brain regional hypoperfusion and hypometabolism. Such brain abnormalities have been found to increase the risk of onset of psychiatric disorder (depression, bipolar and dementia) in old age. Summary As vascular risk factors are potentially modifiable when detected in midlife, the early characterization of brain changes associated with the presence of cardiovascular diseases holds promise to afford clinical applications in psychiatry, providing new perspectives for the prevention of old age psychiatric disorders.