210 resultados para MATRIX INFRARED-SPECTRA


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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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Background: Smooth muscle content is increased within the airway wall in patients with asthma and is likely to play a role in airway hyperresponsiveness. However, smooth muscle cells express several contractile and structural proteins, and each of these proteins may influence airway function distinctly. Objective: We examined the expression of contractile and structural proteins of smooth muscle cells, as well as extracellular matrix proteins, in bronchial biopsies of patients with asthma, and related these to lung function, airway hyperresponsiveness, and responses to deep inspiration. Methods: Thirteen patients with asthma (mild persistent, atopic, nonsmoking) participated in this cross-sectional study. FEV1 % predicted, PC20 methacholine, and resistance of the respiratory system by the forced oscillation technique during tidal breathing and deep breath were measured. Within 1 week, a bronchoscopy was performed to obtain 6 bronchial biopsies that were immunuhistochemically stained for alpha-SM-actin, desmin, myosin light chain kinase (MLCK), myosin, calponin, vimentin, elastin, type III collagen, and fibronectin. The level of expression was determined by automated densitometry. Results: PC20 methacholine was inversely related to the expression of alpha-smooth muscle actin (r = -0.62), desmin (r = -0.56), and elastin (r = -0.78). In addition, FEV1% predicted was positively related and deep inspiration-induced bronchodilation inversely related to desmin (r = -0.60), MLCK (r = -0.60), and calponin (r = -0.54) expression. Conclusion: Airway hyperresponsiveness, FEV1% predicted, and airway responses to deep inspiration are associated with selective expression of airway smooth muscle proteins and components of the extracellular matrix.

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This study evaluated the use of Raman spectroscopy to identify the spectral differences between normal (N), benign hyperplasia (BPH) and adenocarcinoma (CaP) in fragments of prostate biopsies in vitro with the aim of developing a spectral diagnostic model for tissue classification. A dispersive Raman spectrometer was used with 830 nm wavelength and 80 mW excitation. Following Raman data collection and tissue histopathology (48 fragments diagnosed as N, 43 as BPH and 14 as CaP), two diagnostic models were developed in order to extract diagnostic information: the first using PCA and Mahalanobis analysis techniques and the second one a simplified biochemical model based on spectral features of cholesterol, collagen, smooth muscle cell and adipocyte. Spectral differences between N, BPH and CaP tissues, were observed mainly in the Raman bands associated with proteins, lipids, nucleic and amino acids. The PCA diagnostic model showed a sensitivity and specificity of 100%, which indicates the ability of PCA and Mahalanobis distance techniques to classify tissue changes in vitro. Also, it was found that the relative amount of collagen decreased while the amount of cholesterol and adipocyte increased with severity of the disease. Smooth muscle cell increased in BPH tissue. These characteristics were used for diagnostic purposes.

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This study presents the results of Raman spectroscopy applied to the classification of arterial tissue based on a simplified model using basal morphological and biochemical information extracted from the Raman spectra of arteries. The Raman spectrograph uses an 830-nm diode laser, imaging spectrograph, and a CCD camera. A total of 111 Raman spectra from arterial fragments were used to develop the model, and those spectra were compared to the spectra of collagen, fat cells, smooth muscle cells, calcification, and cholesterol in a linear fit model. Non-atherosclerotic (NA), fatty and fibrous-fatty atherosclerotic plaques (A) and calcified (C) arteries exhibited different spectral signatures related to different morphological structures presented in each tissue type. Discriminant analysis based on Mahalanobis distance was employed to classify the tissue type with respect to the relative intensity of each compound. This model was subsequently tested prospectively in a set of 55 spectra. The simplified diagnostic model showed that cholesterol, collagen, and adipocytes were the tissue constituents that gave the best classification capability and that those changes were correlated to histopathology. The simplified model, using spectra obtained from a few tissue morphological and biochemical constituents, showed feasibility by using a small amount of variables, easily extracted from gross samples.

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The present study aims at the use of Raman spectroscopy in the quantification of unsaturated fats in fat-containing foods, compared to the information available in the Nutritional Table, to obtain a non-destructive optical quantification of unsaturation. Raman spectra of edible oil, margarine, mayonnaise, hydrogenated fat, and butter were obtained with a near-infrared Raman spectrometer (830nm). By analyzing selected bands in the regions of 1750, 1660, 1440, 1300, and 1260cm-1, the amount of total and unsaturated fat of samples of oil, margarine, and mayonnaise were correlated with the information displayed in the Nutritional Table. The amount of unsaturated trans fat in selected samples was correlated to the Raman shift of 1660cm-1. Dispersive Raman spectroscopy was shown to be effective in quantifying the unsaturated fats in oil, margarine, and mayonnaise, and trans fat in hydrogenated oils and butter.

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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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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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Prostate cancer (PCa) is the most common type of malignant tumor in Brazilian males. Single nucleotide polymorphisms (SNPs) have been demonstrated to be present in the promoter region of matrix metalloproteinase (MMP) genes and have been associated with the development and progression of some cancers. In this study, our aim was to investigate the association between the polymorphisms of MMP1, 2, 7, and 9 and susceptibility, and their correlation with the classic prognostic parameters of PCa. For genes MMP1, 2 and 9, the frequencies of the polymorphic homozygote genotypes were higher in the control group than in the PCa group (P<0.0001). We conclude that the MMP1, 2 and 9 polymorphisms are more common in the control group than in patients with PCa, and may have a protective effect in the development of this neoplasia.

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The immunopathologic and inflammatory mechanisms involved in periodontal disease (PD) include the participation of host resident, inflammatory cells and chemical mediators. Metalloproteinases (MMPs) and nitric oxide (NO) play essential role in extracellular matrix turnover of periodontal tissue destruction. In this study, by means of RT-PCR through semi-quantitative densitometric scanning methods, the expression of MMPs -2 and -9 and inducible NO synthase (iNOS) was temporally and spatially investigated during the destructive mechanisms of experimentally induced PD in rats. Samples from different periods were microscopically analyzed and compared with the contralateral side (control). Our results showed significant expression of MMP-9 and iNOS in tissues affected by PD, as compared with controls, three days after PD induction, simultaneously with the beginning of alveolar bone loss. At 7 days post induction, only the MMP-9 mRNA presented a significantly higher expression, as compared with the respective controls. Thus, in the rat ligature-induced PD, MMP-9 and iNOS might importantly participate in the early stages of the disease, including inflammatory cell migration, tissue destruction and alveolar bone resorption. Also, we may suggest that the exuberant presence of PMNs may be related to the important expression of iNOS and MMP-9 found at 3 days post induction.

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The strong inflammatory reaction that occurs in the heart during the acute phase of Trypanosoma cruzi infection is modulated by cytokines and chemokines produced by leukocytes and cardiomyocytes. Matrix metalloproteinases (MMPs) have recently emerged as modulators of cardiovascular inflammation. In the present study we investigated the role of MMP-2 and MMP-9 in T. cruzi-induced myocarditis, by use of immunohistochemical analysis, gelatin zymography, enzyme-linked immunosorbent assay, and real-time polymerase chain reaction to analyze the cardiac tissues of T. cruzi-infected C57BL/6 mice. Increased transcripts levels, immunoreactivity, and enzymatic activity for MMP-2 and MMP-9 were observed by day 14 after infection. Mice treated with an MMP inhibitor showed significantly decreased heart inflammation, delayed peak in parasitemia, and improved survival rates, compared with the control group. Reduced levels of cardiac tumor necrosis factor-alpha, interferon-gamma, serum nitrite, and serum nitrate were also observed in the treated group. These results suggest an important role for MMPs in the induction of T. cruzi-induced acute myocarditis.

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Introduction: Fibrinolyis is one of the first line therapies in high risk pulmonary embolism (PE) according to current guidelines. Previous studies showed that brinolytic therapy with tPA (tissue plasminogen activator, or alteplase) upregulates the concentrations of matrix metalloproteinases (MMPs) and contributes to hemorrhagic transformation after cardioembolic stroke. However, no previous study has described the circulating MMPs levels following fibrinolysis for acute PE. Materials and Methods: We serially measured the circulating levels of MMPs (MMP-9 and MMP-2) and their endogenous inhibitors, the tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 in alteplase and in streptokinase-treated patients with acute PE by gelatin zymography and by enzyme-linked immunosorbent assays, respectively. Results: We found that therapy of PE streptokinase or with alteplase is associated increased pro-MMP-9, but not MMP-2, concentrations for up to 24 hours, whereas no significant changes were found in TIMP-1 or TIMP-2 concentrations. This alteration returned to normal 3 to 5 days after thrombolysis. This is the first study reporting on MMPs alterations following fibrinolysis for acute PE. Conclusions: We found transient increases in circulating pro-MMP-9 levels following fibrinolysis for acute PE. Our findings support the hypothesis that increased MMP-9 levels may underlie the risk of intracerebral hemorrhage or other bleeding complication of thrombolysis for acute PE, and the use of MMP inhibitors may decrease such risk. (C) 2010 Elsevier Ltd. All rights reserved.

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Background: Enhanced cardiac matrix metalloproteinase activity (MMPs) has been associated with ventricular remodeling and cardiac dysfunction. It is unknown whether MMPs contribute to systolic/diastolic dysfunction and compensatory remodeling in 2-kidney, 1-clip (2K1C) hypertensive rats. To test this hypothesis, we used 2K1C rats after 2 weeks of surgery treated or not with a nonspecific inhibitor of MMPs (doxycycline). Methods and Results: We found that blood pressure and +/-dP/dt increased in 2K1C rats compared with sham groups, and these parameters were attenuated by doxycycline treatment (P < .05). Doxycycline also reversed cardiac hypertrophy observed in 2K1C rats (P < .05). Hypertensive rats showed increased MMP-2 levels in zymograms and in the tissue by immunofluorescence (P < .05) compared with sham groups. Increased total gelatinolytic activity was observed in untreated 2K1C rats when compared with sham groups (P < .05). Doxycycline decreased total gelatinolytic activity in 2K1C rats to control levels (P < .05). Conclusion: An imbalance in gelatinolytic activity, with increased MMP-2 levels and activity underlies the development of morphological and functional alterations found in the compensatory hypertrophy observed in 2K1C hearts. Because function and structure were restored by doxycycline, the inhibition of MMPs or their modulation may provide beneficial effects for therapeutic intervention in cardiac hypertrophy. (J Cardiac Fail 2010;16:599-608)

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Background: Abnormal production of matrix metalloproteinases (MMPs), especially MMP-9, may play a role in hypertensive disorders of pregnancy. These alterations may result from functional genetic polymorphisms in the promoter region of MMP-9 gene, which are known to change MMP-9 expression. We examined whether 2 MMP-9 polymorphisms (C(-) (1562) T and (CA)n) and haplotypes are associated with preeclampsia and/or gestational hypertension. Methods: We studied 476 pregnant women: 176 healthy pregnant (HP), 146 pregnant with gestational hypertension (GH), and 154 pregnant with preeclampsia (PE). Genomic DNA was extracted from whole blood and genotypes for C(- 1562) T and (CA)n polymorphisms were determined by PCR-RFLP. Haplotype frequencies were inferred using the PHASE ver. 2.1 program. Results: For the g.-90(CA)13-25 polymorphism, no significant differences were found in genotype and allele distributions when PE or GH groups were compared with HP group. However, the CT genotype and T allele for g.-1562C>T polymorphism were more commonly found in GH subjects compared with the HP group (both P<0.05). Conversely, we found no differences in genotypes or allele distributions for the g.-1562C>T polymorphism when the PE and the HP groups were compared. No significant differences were found in overall distributions of haplotype frequencies when the GH or the PE group was compared with the HP group. Conclusions: The C(- 1562) T polymorphism in MMP-9 gene is associated with gestational hypertension, but not with preeclampsia. These findings may help to explain the higher plasma MMP-9 levels previously reported in GH compared with HP. (C) 2010 Elsevier B.V. All rights reserved.

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Altered levels of matrix metalloproteinases (MMPs) may reflect relevant pathogenetic mechanisms of disease conditions. The objective of this study was to compare the plasma levels of MMPs and tissue inhibitors of MMPs (TIMPs) in polycystic ovary syndrome (PCOS) patients with those found in healthy ovulatory controls and to examine whether the levels of these biomarkers are associated with clinical and biochemical features of this syndrome. Sixty-five healthy ovulatory subjects (controls) and 80 patients with PCOS were include in this study. MMP-2, MMP-8, MMP-9, TIMP-1, TIMP-2 concentrations were measured in plasma samples by gelatin zymography or enzyme-linked immunoassays. MMP-2, MMP-8, MMP-9, and TIMP-1 levels were similar in PCOS patients and in healthy controls (P > 0.05). PCOS patients had lower plasma TIMP-2 levels than healthy controls (P < 0.05). We found higher MMP-2/TIMP-2 and MMP-9/TIMP-1 ratios in PCOS patients than in healthy controls (all P < 0.05). Testosterone levels correlated positively with the MMP-9/TIMP-1 ratio and negatively with TIMP-2 levels (r = 0.26, P < 0.01 and r = -0.21, P = 0.02, respectively). In addition, only testosterone was an independent predictor of TIMP-2 levels (estimate = -0.35, P = 0.04) and the MMP-9/TIMP-1 ratio (estimate = 0.01, P = 0.04). We found evidence indicating that the balance between MMPs and TIMPs in women with PCOS is altered, probably due to androgen excess found in these women.