975 resultados para ENDOTHELIAL GROWTH-FACTOR
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We tested the hypothesis that bone marrow-derived mononuclear cells (BMDMCs) at an early phase of cecal ligation and puncture (CLP)-induced sepsis may have lasting effects on: (1) lung mechanics and histology, (2) the structural remodelling of lung parenchyma, (3) lung, kidney, and liver cell apoptosis, and (4) pro- and anti-inflammatory cytokines and growth factors. At day 1, BMDMC significantly reduced mortality, as well as caspase-3, interleukin (IL)-6 and IL-1 beta vascular endothelial growth factor, platelet-derived growth factor, hepatocyte growth factor, and transforming growth factor-beta, but increased IL-10 mRNA expression in lung tissue in septic mice contributing to endothelium and epithelium alveolar repair and improvement of lung mechanics. BMDMC also prevented the increase of apoptotic cells in lung, liver, and kidney. At day 7, these early functional and morphological effects were preserved or further improved. In conclusion, in the present model of sepsis, the beneficial effects of early administration of BMDMCs on lung and distal organs were preserved, possibly by paracrine mechanisms. (C) 2011 Elsevier B.V. All rights reserved.
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We hypothesized that bone marrow-derived mononuclear cells (BMDMC) would attenuate the remodeling process in a chronic allergic inflammation model. C57BL/6 mice were assigned to two groups. In OVA, mice were sensitized and repeatedly challenged with ovalbumin. Control mice (C) received saline under the same protocol. C and OVA were further randomized to receive BMDMC (2 x 10(6)) or saline intravenously 24 h before the first challenge. BMDMC therapy reduced eosinophil infiltration, smooth muscle-specific actin expression, subepithelial fibrosis, and myocyte hypertrophy and hyperplasia, thus causing a decrease in airway hyperresponsiveness and lung mechanical parameters. BMDMC from green fluorescent protein (GFP)-transgenic mice transplanted into GFP-negative mice yielded lower engraftment in OVA. BMDMC increased insulin-like growth factor expression, but reduced interleukin-5, transforming growth factor-beta, platelet-derived growth factor, and vascular endothelial growth factor mRNA expression. In conclusion, in the present chronic allergic inflammation model, BMDMC therapy was an effective pre-treatment protocol that potentiated airway epithelial cell repair and prevented inflammatory and remodeling processes. (C) 2010 Elsevier B.V. All rights reserved.
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P>Background To date, little information has been available about pulmonary artery pathology in asthma. The pulmonary artery supplies the distal parts of the lungs and likely represents a site of immunological reaction in allergic inflammation. The objective of this study was to describe the inflammatory cell phenotype of pulmonary artery adventitial inflammation in lung tissue from patients who died of asthma. Methods We quantified the different inflammatory cell types in the periarterial region of small pulmonary arteries in lung tissue from 22 patients who died of asthma [fatal asthma (FA)] and 10 control subjects. Using immunohistochemistry and image analysis, we quantified the cell density for T lymphocytes (CD3, CD4, CD8), B lymphocytes (CD20), eosinophils, mast cells (chymase and tryptase), and neutrophils in the adventitial layer of pulmonary arteries with a diameter smaller than 500 mu m. Results Our data (median/interquartile range) demonstrated increased cell density of mast cells [FA=271.8 (148.7) cells/mm
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Angiotensin II (Ang II) and vascular endothelial growth factor (VEGF) are important mediators of kidney injury in diabetes. Acute hyperglycemia increased synthesis of intrarenal Ang I and Ang II and resulted in activation of both Ang II receptors, AT1 and AT2, in the kidney. Losartan (specific AT1 antagonist) or PD123319 (specific AT2 antagonist) did not affect hyperglycemia but prevented activation of renal AT1 and AT2, respectively. In murine renal cortex, acute hyperglycemia increased VEGF protein but not mRNA content after 24 h, which suggested translational regulation. Blockade of AT2, but not AT1, prevented increase in VEGF synthesis by inhibiting translation of VEGF mRNA in renal cortex. Acute hyperglycemia increased VEGF expression in wild type but not in AT2 knockout mice. Binding of heterogeneous nuclear ribonucleoprotein K to VEGF mRNA, which stimulates its translation, was prevented by blockade of AT2, but not AT1. The Akt-mTOR-p70(S6K) signaling pathway, involved in the activation of mRNA translation, was activated in hyperglycemic kidneys and was blocked by the AT2 antagonist. Elongation phase is an important step of mRNA translation that is controlled by elongation factor 1A (eEF1A) and 2 (eEF2). Expression of eEF1A and activity of eEF2 was higher in kidney cortex from hyperglycemic mice and only the AT2 antagonist prevented these changes. To assess selectivity of translational control of VEGF expression, we measured expression of fibronectin (FN) and laminin beta 1 (lam beta 1): acute hyperglycemia increased FN expression at both protein and mRNA levels, indicating transcriptional control, and did not affect the expression of lam beta 1. To confirm results obtained with PD123319, we induced hyperglycemia in AT2 knockout mice and found that in the absence of AT2, translational control of VEGF expression by hyperglycemia was abolished. Our data show that acute hyperglycemia stimulates Ang II synthesis in murine kidney cortex, this leads to AT2 activation and stimulation of VEGF mRNA translation, via the Akt-mTOR-p70(S6K) signaling pathway. Our data show that exclusive translational control of protein expression in the kidney by acute hyperglycemia is not a general phenomenon, but do not prove that it is restricted to VEGF. (C) 2010 Elsevier Inc. All rights reserved.
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SETTING: A tertiary care research centre in Sao Paolo, Brazil. OBJECTIVE: To quantify interleukin (IL) 8, tumour necrosis factor alpha (TNF-alpha), vascular endothelial growth factor (VEGF) and transforming growth factor beta(1), (TGF-beta(1))in pleural fluid from tuberculous patients, correlating its values with the histopathological patterns in pleural biopsies. DESIGN: Cytokines were quantified in patients with transudatcs secondary to congestive heart failure (n = 8) and exudates secondary to tuberculosis (TB; n = 39). In parietal pleural biopsies from TB patients, the histological patterns of the inflammatory response were quantified by morphometric analysis (stereological point-counting method). RESULTS: IL-8, TNF-alpha, VEGF and TGF-beta(1) levels were higher in TB than in transudates. A positive correlation existed between components of the fibrinoid exudative phase with pleural fluid IL-8 (R = 0.52, P = 0.004) and VEGF (R = 0.42, P = 0.0021) levels. A negative correlation existed between pleural fluid IL-8 (R = -0.37, P = 0.048) and VEGF (R = -0.44, P = 0.0015) levels with tissue components of fibroproliferation. CONCLUSION: The high pleural levels of TNF-a, IL-8, VEGF and TGF-beta(1) suggest the involvement of these cytokines in the TB immunological response. The positive correlation between pleural fluid IL-8 and VEGF with the components of the acute exudative phase and the negative correlation between these cytokines with the fibroproliferative components suggest a temporary inflammatory response in the pleural space.
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Thyroid cancer is the most frequent endocrine neoplasia worldwide. The route for metastasis and loco-regional invasion preferentially occurs by lymphatic vessels. For this reason, the assessment of lymphatic vessel density (LVD) is supposed to represent both a prognostic parameter and also a potential therapeutic target. In order to evaluate the value of LVD in benign and malignant thyroid lesions, we analyzed 110 thyroidectomy specimens using D2-40, a specific marker for lymphatic vessels and vascular endothelial growth factor C (VEGF-C), the most potent molecule of lymphatic proliferation. LVD was significantly different between papillary and follicular carcinomas in total (p = 0.045) and peritumoral area (p = 0.042). Follicular adenoma and follicular carcinoma showed an important difference of intra- (p = 0.019) and peritumoral (p = 0.033) LVD. VEGF-C was more markedly expressed in malignancies than in benignant lesions (p = 0.0001). Almost all cancers with high positive VEGF-C expression also exhibited increased peritumoral LVD (p = 0.049) when compared with the benignant lesions. Indeed, the high peritumoral LVD of malignant thyroid lesions is an important finding for surgery planning and supports the practice of total thyroidectomy in malignant thyroid neoplasm`s since the lymphatic peritumoral vessels definitely are an escape path for tumor cells.
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Background. Lung transplantation is the procedure of choice in several end-stage lung diseases. Despite improvements in surgical techniques and immunosuppression, early postoperative complications occur frequently. Objective. To evaluate the pleural inflammatory response after surgery. Patients and Methods. Twenty patients aged 18 to 63 years underwent unilateral or bilateral lung transplantation between August 2006 and March 2008. Proinflammatory cytokines interleukin (IL)-1 beta, IL-6, and IL-8 and vascular endothelial growth factor in pleural fluid and serum were analyzed. For cytokine evaluation, 20-mL samples of pleural fluid and blood (right, left, or both chest cavities) were obtained at 6 hours after surgery and daily until removal of the chest tube or for a maximum of 10 days. Data were analyzed using analysis of variance followed by the Holm-Sidak test. Results. All effusions were exudates according to Light`s criteria. Pleural fluid cytokine concentrations were highest at 6 hours after surgery. Serum concentrations were lower than those in pleural fluid, and IL-1 beta, IL-6, and IL-8 were undetectable at all time points. Conclusions. There is a peak concentration of inflammatory cytokines in the first 6 hours after transplantation, probably reflecting the effects of surgical manipulation. The decrease observed from postoperative day 1 and thereafter suggests the action of the immunosuppression agents and a temporal reduction in pleural inflammation.
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Intrapleural instillation of talc has been used in the treatment of recurrent pleural effusions but can, in rare instances, result in respiratory failure. Side-effects seem to be related to composition, size and inflammatory power of talc particles. The aim of this study was to evaluate the inflammatory response to intrapleural injection of talc containing small particles (ST) or talc containing particles of mixed size (MT). 100 rabbits received intrapleural talc, 50 with ST (median 6.41 mu m) and 50 with MT median 21.15 mu m); the control group was composed of 35 rabbits. Cells, lactate dehydrogenase, C-reactive protein (CRIP), interleukin (IL)-8 and vascular endothelial growth factor were evaluated in serum and bronchoalveolar lavage at 6, 24, 48, 72 and 96 h. Lung histology and the presence of talc were also analysed. Statistics were performed using ANOVA and an unpaired t-test. Most of the parameters showed greater levels in the animals injected with talc than in the controls, suggesting a systemic and pulmonary response. Higher serum levels of CRP and IL-8 were observed in the animals injected with ST. Talc particles were observed in both lungs with no differences between groups. Lung cell infiltrate was more evident in the ST group. In conclusion, talc with larger particles should be the preferred choice in clinical practice in order to induce safer pleurodesis.
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Background: The intrapleural instillation of a sclerosing agent produces an inflammatory process frequently followed by pain. The treatment can include the use of analgesics or anti-inflammatory drugs. Previously, it was demonstrated (experimental studies) that corticoids and nonsteroidal anti-inflammatory drugs (diclofenac) reduce the inflammation and fibrosis produced by talc but not by transforming growth factor-P or silver nitrate. The objective of this study was to determine whether parecoxib (COX-2 inhibitor) affects pleurodesis induced by talc or silver nitrate. Methods: 140 rabbits received intrapleural. injection (2 mL) of 400 mg/kg of talc or 0.5% silver nitrate. A subgroup of 70 animals received additional daily intramuscular parecoxib (1 mg/kg). They were sacrificed at 4, 24, 48, 72 h or 7, 14, or 28 days after the procedure. The pleural fluid was quantified; biochemical examinations (glucose, lactic dehydrogenase, and proteins) and immunologic dosages (interleukin-8, vascular endothelial growth factor, and transforming growth factor-beta(1)) were analyzed in pleural fluid and blood. Finally, macro- and microscopic pleura and lung studies were performed. Results: Evaluation after 28 days demonstrated that parecoxib reduced pleural and pulmonary inflammation but not pleural adhesions. The changes were observed precociously (72 h) and were more evident after silver nitrate injection. Conclusion: Systemic parecoxib injection does not interfere with talc or silver nitrate pleurodesis. These results suggest that use of COX-2 inhibitors can be considered and depending of the results of other studies, recommended in human pleurodesis. (c) 2008 Elsevier Ltd. All rights reserved.
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Objective: To analyze the prognostic effect of epidermal growth factor receptor (EGFR), matrix metalloproteinases 2 and 9, and vascular endothelial growth factor expression in patients with locally recurrent oral carcinoma after salvage surgery. Design: Retrospective cohort study. Settings: Tertiary center cancer hospital. Patients: The charts of 111 patients with local recurrence of oral carcinomas were retrospectively analyzed. The previous treatment consisted of surgery in 33 patients (30.0%), radiotherapy with or without chemotherapy in 46 patients (41.0%), and surgery with adjuvant radiotherapy in 32 patients (29.0%). The expression of EGFR, matrix metalloproteinases 2 and 9, and vascular endothelial growth factor was analyzed with a tissue microarray immunohistochemical technique. Main Outcome Measures: Overall survival and cancer-specific survival (CSS). Results: The recurrences were diagnosed in less than 1 year in 69 patients (62.2%) and in more than 1 year in 42 patients (37.8%). The prognosis was worse in the group with the disease-free interval of less than 1 year (P=.01). Patients with more advanced disease (clinical stage of recurrence, III/IV) had worse rates of CSS (P=.04). Cases that were positive for EGFR had a 3-year CSS of 27.2%, while EGFR-negative cases had a 3-year CSS of 64.3% (P=.001). The expression of matrix metalloproteinases 2 (P=.83) and 9 (P=.15) and vascular endothelial growth factor (P=.86) was not significant in this group. In multivariate analysis, only the disease-free interval and the overexpression of EGFR were associated with a higher risk of cancer death. Conclusions: Local recurrence in oral carcinomas carries a poor prognosis. A disease-free interval of more than 1 year and a EGFR-negative expression are the main prognostic factors related to better CSS in patients treated with salvage surgery.
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Purpose: To describe the presence of iris neovascularization in a rabbit-model of retinal neovascularization induced by the intravitreal injection of latex-derived angiogenic fraction microspheres (LAF). Materials and Methods: Eight New Zealand rabbits received one intravitreal injection of PLGA (L-lactide-coglycolide) microspheres with 50 ug of LAF in the right eye (Group A). Microspheres without the LAF (0.1 ml) were injected in controls (Group B; n = 8). Follow-up with clinical evaluation and iris fluorescein angiography was performed after 4 weeks when eyes were processed for light microscopy. Results: All eyes from Group A showed significant vascular dilation, conjunctival hyperemia and neovascularization on the iris surface, after LAF injection. No vascular changes were observed in Group B. Conclusions: The intravitreal injection of microspheres containing the LAF can induce rubeosis iridis in rabbits and could be used as a simple experimental model for iris neovascularization.
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Increases in vascular permeability and angiogenesis are crucial events to wound repair, tumoral growth and revascularization of tissues submitted to ischemia. An increased vascular permeability allows a variety of cytokines and growth factors to reach the damaged tissue. Nevertheless, the angiogenesis supply tissues with a wide variety of nutrients and is also important to metabolites clearance. It has been suggested that the natural latex from Hevea brasiliensis showed wound healing properties and angiogenic activity. Thus, the purpose of this work was to characterize its angiogenic activity and its effects on vascular permeability and wound healing. The serum fraction of the latex was separated from the rubber with reduction of the pH. The activity of the dialyzed serum fraction on the vascular permeability injected in subcutaneous tissue was assayed according Mile`s method. The angiogenic activity was determined using a chick embryo chorioallantoic membrane assay and its effects on the wound-healing process was determined by the rabbit ear dermal ulcer model. The serum fraction showed evident angiogenic effect and it was effective in enhancing vascular permeability. In dermal ulcers, this material significantly accelerated wound healing. Moreover, the serum fraction boiled and treated with proteases lost these activities. These results are in accordance with the enhancement of wound healing observed in clinical trials carried out with a biomembrane prepared with the same natural latex. Copyright (C) 2009 John Wiley & Sons, Ltd.
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Purpose: To create a retinal neovascularization experimental model using intravitreal injection of microspheres loaded with latex-derived angiogenic fraction. Methods: Thirty-two albino New Zealand rabbits, divided in 4 groups of 8 animals, were enrolled in this study. Rabbits in groups I, II, and III received one intravitreal injection of PLGA (L-lactide-co-glycolide) microspheres with 10, 30, and 50 mu g of latex-derived angiogenic fraction into their right eyes, respectively, and group IV received 0.1 ml of microspheres without the angiogenic fraction. Weekly follow-up with ophthalmoscopy and fluorescein angiography was performed; the rabbits were sacrificed in the 4th week and their eyes processed for light microscopy. Results: All eyes from group I demonstrated increased retinal vascular tortuosity, observed from 14 days after injection and maintained for 28 days, otherwise without new vessels detection. All group II eyes showed vascular changes similar to group I. Fifty percent of the eyes from group II rabbits developed retinal neovascularization 21 days after injection. All eyes from group III demonstrated significant vascular tortuosity and retinal new vessels 2 weeks after injection, progressing to fibrovascular proliferation and tractional retinal detachment. No vascular changes or retinal new vessels were observed in group IV eyes. Light microscopy confirmed the existence of new vessels previously seen on fluorescein angiography, in retinal sections adjacent to the optic disc, not observed in sections at the same area in the control group. Conclusion: Thirty- and 50-mu g microspheres containing latex-derived angiogenic fraction injected into the vitreous cavity induced retinal neovascularization in rabbits.
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To review and discuss the pathophysiology and prevention strategies for ovarian hyperstimulation syndrome (OHSS), which is a condition that may occur in up to 20% of the high risk women submitted to assisted reproductive technology cycles. The English language literature on these topics were reviewed through PubMed and discussed with emphasis on recent data. The role of estradiol, luteinizing hormone, human chorionic gonadotropin (hCG), inflammatory mediators, the renin-angiotensin system and vascular endothelial growth factor is discussed in the pathophysiology of OHSS. In addition we consider the prevention strategies, including coasting, administration of albumin, renin-angiotensin system blockage, dopamine agonist administration, non-steroidal anti-inflammatory administration, GnRH antagonist protocols, reducing hCG dosage, replacement of hCG and in vitro maturation of oocytes (IVM). Among the many prevention strategies that have been discussed, the current evidence points to the replacement of hCG by GnRH agonists in antagonist cycles and the performance of IVM procedures as the safest approaches.
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PURPOSE: To evaluate the effects of intravitreal bevacizumab in patients with diabetic macular edema (DME) associated with severe capillary loss. DESIGN: Multicenter, open-label, nonrandomized study. METHODS: SETTING: Two tertiary ophthalmic referral centers in Brazil. STUDY POPULATION: Ten consecutive patients with DME and ""severe"" capillary loss. OBSERVATION PROCEDURES: Intravitreal injection(s) of bevacizumab (1.5 mg). Standardized ophthalmic evaluation was performed at baseline and at weeks 8, 16, 24, and 54. MAIN OUTCOME MEASURES: Changes in best-corrected visual acuity (BCVA) and in optical coherence tomography variables (central macular thickness [CMT] and total macular volume [TMV]). RESULTS: Significant changes in BCVA and in CMT/TMV were noted throughout the study (P<.001, P=.009, and P<.001, respectively). The mean logarithm of the minimal angle of resolution Early Treatment Diabetic Retinopathy Study BCVA was 0.786 (similar to 20/125(+1)) at baseline, 0.646 (similar to 20/80(-2)) at week 8, 0.580 (20/80(+1)) at week 16, 0.574 (similar to 20/80(+1)) at week 24, and 0.558 (similar to 20/80(+2)) at week 54. Compared with baseline, a significant change in BCVA was noted at all follow-up visits (P <=.008). The mean CMT/TMV values were, respectively, 472.6/10.9 at baseline, 371.4/9.9 at week 8, 359.5/9.8 at week 16, 323.9/9-4 at week 24, and 274.6/8.7 at week 54. Compared with baseline, a significant change in both CMT and TMV was noted only at 24 and 54 weeks (P <=.007). At 54 weeks, fluorescein angiography demonstrated no change in the extent of macular capillary loss and reduced dye leakage as compared with baseline in all patients. CONCLUSIONS: Favorable changes in BCVA and in CMT/TMV observed throughout 1 year suggest that intra-vitreal bevacizumab may be a viable alternative treatment for the management of patients with DME and severe capillary loss. (Am J Ophthalmol 2009;147:1022-1030. (C) 2009 by Elsevier Inc. All rights reserved.)