245 resultados para Matrix Function


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Meconium (MEC) is a potent inactivator of pulmonary surfactant. The authors studied the effects of polyethylene glycol addition to the exogenous surfactant over the lung mechanics and volumes. Human meconium was administrated to newborn rabbits. Animals were ventilated for 20 minutes and dynamic compliance, ventilatory pressure, and tidal volume were recorded. Animals were randomized into 3 study groups: MEC group (without surfactant therapy); S100 group (100 mg/kg surfactant); and PEG group (100 mg/kg porcine surfactant plus 5% PEG). After ventilation, a pulmonary pressure-volume curve was built. Histological analysis was carried out to calculate the mean alveolar size (Lm) and the distortion index (DI). Both groups treated with surfactant showed higher values of dynamic pulmonary compliance and lower ventilatory pressure, compared with the MEC group (P .05). S100 group had a larger maximum lung volume, V30, compared with the MEC group (P .05). Lm and DI values were smaller in the groups treated with surfactant than in the MEC group (P .05). No differences were observed between the S100 and PEG groups. Animals treated with surfactant showed significant improvement in pulmonary function as compared to nontreated animals. PEG added to exogenous surfactant did not improve lung mechanics or volumes.

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Aims: To compare septal and vascular matrix remodelling, vascular occlusion, Pulmonary function tests and survival between two groups: one with idiopathic non-specific interstitial pneumonia (NSIP) and one with NSIP associated with systemic sclerosis (SSc). Methods and results: Pulmonary biopsy specimens were examined from 40 patients, 22 with NSIP and 18 with NSIP associated with SSc. The content of septal collagen and elastic fibres, as well as the elastic fibres in the vascular interstitium, were higher in the SSc group (P = 0.01, P = 0.001 and P < 0.0001, respectively). Among pulmonary function tests. the diffusing capacity for carbon monoxide/alveolar volume was affected to a greater extent in the SSc group (59%) of the predicted value in SSc and 97% in the idiopathic group). There were no differences in collagen content of the vascular interstitium, arterial occlusion, or survival between the two groups. Conclusions: Although the fibrotic process is more intense in the SSc group. it, does not affect the prognosis of these patients. Because the elastotic process is higher in the SSc group, this might suggest that autoimmune inflammatory mechanisms affecting the elastic fibre system play a greater role in the pathogenesis and pulmonary remodelling process of SSc NSIP than in idiopathic NSIP.

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There is an intimate relationship between the extracellular matrix (ECM) and smooth muscle cells within the airways. Few studies have comprehensively assessed the composition of different ECM components and its regulators within the airway smooth muscle (ASM) in asthma. With the aid of image analysis, the fractional areas of total collagen and elastic fibres were quantified within the ASM of 35 subjects with fatal asthma (FA) and compared with 10 nonfatal asthma (NFA) patients and 22 nonasthmatic control cases. Expression of collagen I and III, fibronectin, versican, matrix metalloproteinase (MMP)-1, -2, -9 and -12 and tissue inhibitor of metalloproteinase-1 and -2 was quantified within the ASM in 22 FA and 10 control cases. In the large airways of FA cases, the fractional area of elastic fibres within the ASM was increased compared with NFA and controls. Similarly, fibronectin, MMP-9 and MMP-12 were increased within the ASM in large airways of FA cases compared with controls. Elastic fibres were increased in small airways in FA only in comparison with NFA cases. There is altered extracellular matrix composition and a degradative environment within the airway smooth muscle in fatal asthma patients, which may have important consequences for the mechanical and synthetic functions of airway smooth muscle.

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Oral tolerance attenuates changes in in vitro lung tissue mechanics and extracellular matrix remodeling induced by chronic allergic inflammation in guinea pigs. J Appl Physiol 104: 1778-1785, 2008. First published April 3, 2008; doi:10.1152/japplphysiol.00830.2007.-Recent studies emphasize the presence of alveolar tissue inflammation in asthma. Immunotherapy has been considered a possible therapeutic strategy for asthma, and its effect on lung tissue had not been previously investigated. Measurements of lung tissue resistance and elastance were obtained before and after both ovalbumin and acetylcholine challenges. Using morphometry, we assessed eosinophil and smooth muscle cell density, as well as collagen and elastic fiber content, in lung tissue from guinea pigs with chronic pulmonary allergic inflammation. Animals received seven inhalations of ovalbumin (1-5 mg/ml; OVA group) or saline (SAL group) during 4 wk. Oral tolerance (OT) was induced by offering ad libitum ovalbumin 2% in sterile drinking water starting with the 1st inhalation (OT1 group) or after the 4th (OT2 group). The ovalbumin-exposed animals presented an increase in baseline and in postchallenge resistance and elastance related to baseline, eosinophil density, and collagen and elastic fiber content in lung tissue compared with controls. Baseline and post-ovalbumin and acetylcholine elastance and resistance, eosinophil density, and collagen and elastic fiber content were attenuated in OT1 and OT2 groups compared with the OVA group. Our results show that inducing oral tolerance attenuates lung tissue mechanics, as well as eosinophilic inflammation and extracellular matrix remodeling induced by chronic inflammation.

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Along the aluminum refining process, alumina (Al(2)O(3)) constitutes the main source of dust. Although aluminum refinery workers present respiratory symptoms with lung functional changes, no conclusive data about lung function impairment after alumina exposure has been so far reported. We examined the pulmonary alterations of exposure to material collected in an aluminum refinery in Brazil. BALB/c mice were exposed in a whole-body chamber for 1 h to either saline (CTRL, n = 11) or to a suspension (in saline) of 8 mg/m(3) of the dust (ALUM, n = 11) both delivered by an ultrasonic nebulizer. Twenty-four hours after exposure lung mechanics were measured by the end-inflation method. Lungs were prepared for histology. ALUM showed significantly higher static elastance (34.61 +/- 5.76 cmH(2)O/mL), elastic component of viscoelasticity (8.16 +/- 1.20 cmH(2)O/mL), pressure used to overcome the resistive component of viscoelasticity (1.62 +/- 0.24 cmH(2)O), and total resistive pressure (2.21 +/- 0.49 cmH(2)O) than CTRL (27.95 +/- 3.63 cmH(2)O/mL, 6.12 +/- 0.99 cmH(2)O/mL, 1.23 +/- 0.19 cmH(2)O, and 1.68 +/- 0.23 cmH(2)O, respectively). ALUM also presented significantly higher fraction area of alveolar collapse (69.7 +/- 1.2%) and influx of polymorphonuclear cells (27.5 +/- 1.1%) in lung parenchyma than CTRL (27.2 +/- 1.1% and 14.6 +/- 0.7%, respectively). The composition analysis of the particulate matter showed high concentrations of aluminum. For the first time it was demonstrated in an experimental model that an acute exposure to dust collected in an aluminum producing facility impaired lung mechanics that could be associated with inflammation.

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Background and Aim: It is unclear to what extent diabetes modulates the ageing-related adaptations of cardiac geometry and function. Methods and Results: We examined 1005 adults, aged 25-74 years, from a population-based survey at baseline in 1994/5 and at follow-up in 2004/5. We compared persistently non-diabetic individuals (ND; no diabetes at baseline and at follow-up, n = 833) with incident (ID; non-diabetic at baseline and diabetic at follow-up, n = 36) and with prevalent diabetics (PD; diabetes at baseline and follow-up examination, n = 21). Left ventricular (LV) geometry and function were evaluated by echocardiography. Statistical analyses were performed with multivariate linear regression models. Over ten years the PD group displayed a significantly stronger relative increase of LV mass (+9.34% vs. +23.7%) that was mediated by a more pronounced increase of LV end-diastolic diameter (+0% vs. +6.95%) compared to the ND group. In parallel, LA diameter increased (+4.50% vs. +12.7%), whereas ejection fraction decreased (+3.02% vs. -4.92%) more significantly in the PD group. Moreover, at the follow-up examination the PD and ID groups showed a significantly worse diastolic function, indicated by a higher E/EM ratio compared with the ND group (11.6 and 11.8 vs. 9.79, respectively). Conclusions: Long-standing diabetes was associated with an acceleration of age-related changes of left ventricular geometry accumulating in an eccentric remodelling of the left ventricle. Likewise, echocardiographic measures of systolic and diastolic ventricular function deteriorated more rapidly in individuals with diabetes. (C) 2009 Elsevier B.V. All rights reserved.

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Brain-derived neurotrophic factor (BDNF) is the most widely distributed neurotrophin in the CNS, where it plays several pivotal roles in synaptic plasticity and neuronal survival. As a consequence, BDNF has become a key target in the physiopathology of several neurological and psychiatric diseases. Recent studies have consistently reported altered levels of BDNF in the circulation (i.e., serum or plasma) of patients with major depression, bipolar disorder, Alzheimer`s disease, Huntington`s disease and Parkinson`s disease. Correlations between serum BDNF levels and affective, cognitive and motor symptoms have also been described. BDNF appears to be an unspecific biomarker of neuropsychiatric disorders characterized by neurodegenerative changes.

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Objective: Prostate cancer (PCa) is the most frequent tumor in males in Brazil. Single nucleotide polymorphisms (SNP) have been demonstrated in the promoter region of matrix metalloproteinases (MMPs) genes and have been associated with development and progression of some cancers. In this study, our aim was to investigate a possible relation between polymorphism of the promoter region of the MMP2 gene and classical prognostic parameters in prostate cancer. Materials and methods: Genomic DNA was extracted using conventional protocols. The DNA sequence containing the polymorphic site was amplified by real-time polymerase chain reaction, using fluorescent probes (TaqMan). Results: In patients with tumors of a higher stage (pT3), a polymorphic allele in the MMP2 gene was more frequent (P = 0.026) than in patients with lower tumor stage. A polymorphic allele in the MMP2 gene was more frequent in Gleason >= 7 than in Gleason <= 6 (P = 0.042). Conclusions: We conclude that MMP2 polymorphism can be used together with pathological stage and Gleason score to identify patients with worse prognosis. Our results illustrate the potential use of MMP2 SNP as a molecular marker for prostate cancer. (C) 2010 Elsevier Inc. All rights reserved.

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OBJECTIVE: This study was conducted to investigate the success rate of using the facial motor evoked potential (FMEP) of orbicularis oculi and oris muscles for facial nerve function monitoring with use of a stepwise protocol, and its usefulness in predicting facial nerve outcome during cerebellopontine angle (CPA) surgeries. METHODS: FMEPs were recorded intraoperatively from 60 patients undergoing CPA surgeries. Transcranial electrocortical stimulation (TES) was performed using corkscrew electrodes positioned at hemispheric montage (C3/C4 and CZ). The contralateral abductor pollicis brevis muscle was used as the control response. Stimulation was always applied contralaterally to the affected side using 1, 3, or 5 rectangular pulses ranging from 200 to 600 V with 50 mu s of pulse duration and an interstimulus interval of 2 ms. Facial potentials were recorded from needles placed in the orbicularis oculi and oris muscles. RESULTS: FMEP from the orbicularis oris and oculi muscles could be reliably monitored in 86.7% and 85% of the patients, respectively. The immediate postoperative facial function correlated significantly with the FMEP ratio in the orbicularis oculi muscle at 80% amplitude ratio (P =.037) and orbicularis oris muscle at 35% ratio (P =.000). FMEP loss was always related to postoperative facial paresis, although in different degrees. CONCLUSION: FMEPs can be obtained reliably by using TES with 3 to 5 train pulses. Stable intraoperative FMEPs can predict a good postoperative outcome of facial function. However, further refinements of this technique are necessary to minimize artifacts and to make this method more reliable.

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Background. Renal failure is the most important comorbidity in patients with heart transplantation, it is associated with increased mortality. The major cause of renal dysfunction is the toxic effects of calcineurin inhibitors (CNI). Sirolimus, a proliferation signal inhibitor, is an imunossupressant recently introduced in cardiac transplantation. Its nonnephrotoxic properties make it an attractive immunosuppressive agent for patients with renal dysfunction. In this study, we evaluated the improvement in renal function after switching the CNI to sirolimus among patients with new-onset kidney dysfunction after heart transplantation. Methods. The study included orthotopic cardiac transplant (OHT) patients who required discontinuation of CNI due to worsening renal function (creatinine clearance <50 mL/min). We excluded subjects who had another indication for initiation of sirolimus, that is, rejection, malignancy, or allograft vasculopathy. The patients were followed for 6 months. The creatinine clearance (CrCl) was estimated according to the Cockcroft-Gault equation using the baseline weight and the serum creatinine at the time of introduction of sirolimus and 6 months there after. Nine patients were included, 7 (78%) were males and the overall mean age was 60.1 +/- 12.3 years and time since transplantation 8.7 +/- 6.1 years. The allograft was beyond 1 year in all patients. There was a significant improvement in the serum creatinine (2.98 +/- 0.9 to 1.69 +/- 0.5 mg/dL, P = .01) and CrCl (24.9 +/- 6.5 to 45.7 +/- 17.2 mL/min, P = .005) at 6 months follow-up. Conclusion. The replacement of CNI by sirolimus for imunosuppressive therapy for patients with renal failure after OHT was associated with a significant improvement in renal function after 6 months.

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We investigated the effects of salbutamol on the markers of epithelial function in a murine model of chronic allergic pulmonary inflammation by recording the ciliary beat frequency (CBF) and the transepithelial potential difference (PD) in vivo. Mice were sensitized and received four challenges of ovalbumin (OVA group) or 0.9% saline (control group). Forty-eight hours after the 4th inhalation, we observed eosinophilia in the bronchoalveolar lavage and epithelium remodeling with stored acid mucus in the OVA group (P < 0.001). No difference in the baseline CBF was noticed between the groups; however, the OVA group had a significantly lower baseline PD (P = 0.013). Salbutamol increased the CBF in all groups studied, and the dose response curve to salbutamol increased the PD in the OVA group from 10(-4) M to 10(-2) M. We suggest that salbutamol affects the CBF and the depth of the periciliary layer, which, in great part, determines the ability of the cilia to propel the mucus layer. This effect may have a positive impact on airway mucociliary transport in asthma and may have clinical implications. (C) 2011 Elsevier B.V. All rights reserved.

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P>Natural killer (NK) cells bridge the interface between innate and adaptive immunity and are implicated in the control of herpes simplex virus 2 (HSV-2) infection. In subjects infected with human immunodeficiency virus 1 (HIV-1), the critical impact of the innate immune response on disease progression has recently come into focus. Higher numbers of NK cells are associated with lower HIV-1 plasma viraemia. Individuals with the compound genotype of killer cell immunoglobulin-like receptor (KIR) 3DS1 and human leucocyte antigen (HLA)-Bw4-80I, or who have alleles of KIR3DL1 that encode proteins highly expressed on the NK cell surface, have a significant delay in disease progression. We studied the effect of HSV-2 co-infection in HIV-1-infected subjects, and show that HSV-2 co-infection results in a pan-lymphocytosis, with elevated absolute numbers of CD4+ and CD8+ T cells, and NK cells. The NK cells in HSV-2 co-infected subjects functioned more efficiently, with an increase in degranulation after in vitro stimulation. The number of NK cells expressing the activating receptors NKp30 and NKp46, and expressing KIR3DL1 or KIR3DS1, was inversely correlated with HIV-1 plasma viral load in subjects mono-infected with HIV-1, but not in subjects co-infected with HSV-2. This suggests that HSV-2 infection mediates changes within the NK cell population that may affect immunity in HIV-1 infection.

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Purpose: Prostate cancer is the most common tumor in males in Brazil. Single nucleotide polymorphisms have been demonstrated to exist in the promoter regions of matrix metalloproteinase genes and they are associated with the development and progression of some cancers. We investigated the correlation between MMP1, 2, 7 and 9 polymorphisms with susceptibility to prostate cancer, and classic prognostic parameters of prostate cancer. Materials and Methods: Genomic DNA was extracted using conventional protocols. The DNA sequence containing the polymorphic site was amplified by realtime polymerase chain reaction using TaqMan (R) fluorescent probes. Results: For the MMP1 gene the polymorphic allele was more common in the control group than in the prostate cancer group (p <0.001). For the MMP9 gene the incidence of the polymorphic homozygote genotype was higher in the prostate cancer group (p <0.001). For higher stage tumors (pT3) a polymorphic allele in the MMP2 gene was more common (p = 0.026). When considering Gleason score, the polymorphic homozygote genotype of MMP9 was more common in Gleason 6 or less tumors (p = 0.003), while a polymorphic allele in the MMP2 gene was more common in Gleason 7 or greater tumors (p = 0.042). Conclusions: MMP1 and MMP2 may protect against prostate cancer development and MMP9 may be related to higher risk. In contrast, MMP9 polymorphism was associated with a lower Gleason score and MMP2 polymorphism was associated with nonorgan confined disease.

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Melanonychia, from the Greek melaina, means black and is the result of an increased deposition of melanin on the nail plate, originating in the nail matrix. It may have different causes, including subungueal melanoma, making early etiologic diagnosis very important.

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Background. Prior to the introduction of enzyme replacement therapy (ERT), management of Fabry disease (FD) consisted of symptomatic and palliative measures. ERT has been available for several years using recombinant human agalsidase alfa, an analogue of alpha-galactosidase A (GALA). However, the limitations of ERT in improving kidney function have not been established. This study evaluates the safety and therapeutic effect of agalsidase alfa replacement in terms of kidney function and reduction in 24-hour proteinuria. Methods. During the period between January 1, 2002, and August 1, 2005, nine Fabry patients (7 male, 2 female) were treated according to protocol, receiving 0.2 mg/kg agalsidase alfa IV every two weeks. Kidney function was evaluated by measuring the glomerular filtration rate (GFR) using chromium ethylene diamine tetra-acetate clearance ((51)Cr-EDTA mL/min/1.73 m(2)) at baseline, 12, 24, and 36 months. 24-hour proteinuria was measured at baseline, 3, 6, 12, 18, 24, and 36 months of ERT. Kidney disease was classified according to National Kidney Foundation Disease Outcome Quality Initiative (NKF/DOQI) Advisory Board criteria, which define stage I chronic kidney disease (CKD) as GFR >= 90mL/min/1.73 m(2), stage II as 60-89 mL/min/1.73m(2), stage III as 30-59 mL/min/1.73 m(2), stage IV as 15-29 mL/min/1.73m(2), and stage V as < 15 mL/min/1.73m(2). Results. Six patients completed 36 months of therapy, 2 patients completed 18 months, and 1 patient completed 12 months. Mean patient age at baseline was 34.6 +/- 11.3 years. During the study period, kidney function remained stable in patients with stages I, II, or III CKD. One patient, who entered the study with stage IV CKD, progressed to end-stage chronic kidney disease, beginning hemodialysis after 7 months and receiving a kidney transplant after 12 months of ERT. Proteinuria also remained stable in the group of patients with pathologic proteinuria. The use of agalsidase alfa was well tolerated in 99.5% of the infusions administered. Conclusion. Over the course of 36 months of ERT, there was no change in kidney function and 24-hour proteinuria. This suggests thatagalsidase alfa may slow or halt the progression of kidney disease when used before extensive kidney damage occurs. No significant side effects were observed with ERT during the course of the study.