998 resultados para MMP-13
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For many years proof that the hypoxic nature of malignant tumours can be used to selectively target anticancer drugs has been sought. Several classes of potential redox activated anticancer drugs have been developed to take advantage of the reducing environment resulting from the hypoxia. Drug complexes with redox active metal centres as carriers have been investigated, but have largely been employed with cytotoxic drugs that require release of the drug intracellularly, complicating the design of such complexes. MMP inhibitors, a new class of anticancer drug, conversely act in the extracellular environment and we have investigated inhibitor complexes with several redox active transition metals. Marimastat is an MMP inhibitor with potent in-vitro antimetastatic activity and was recently in Phase III clinical trials for a variety of cancer types. We have synthesised a Co(II1) complex of marimastat incorporating the tetradentate ligand tpa (tris(2-methylpyridyl)amine) as a carrier ligand. The complex was structurally characterised in the solid state by single crystal X-ray diffraction, the first example of a crystal structure containing marimastat. 2D COSY and NOESY NMR spectra showed that the complex exists in two isomeric forms in solution, corresponding to the cis and trans isomers yet only crystallises in one of these forms. Biological testing of the complex in mice with 4T1.2 tumours showed interesting and unexpected outcomes. Initial results of the tumour growth inhibition study showed that a significant inhibition of growth was exhibited by the complex over the free inhibitor and the control. However, the metastatic potential of both free marimastat and the complex were higher than the control indicating likely problems with the experimental protocol. Further experiments are needed to determine the potential of such complexes as hypoxia activated prodrugs but there appears at least to be some promise.
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Inorganic nutrients play a critical role in determining benthic community structure in tropical seas. This study examined the impact of adding inorganic nutrients (ammonium and phosphate) on the isotopic composition of 2 reef-building corals, Pocillopora damicornis and Heliofungia actiniformis, on the southern Great Barrier Reef. The addition of elevated nutrients to patch reefs that pond at low tide did not perturb the C:N ratio of either species or their symbiotic dinoflagellates. The C:N ratios were significantly higher in material extracted from the skeleton (14.8 +/- 1.50 and 10.8 +/- 1.42) than either host (7.6 +/- 0.87 and 6.0 +/- 0.71) or symbiotic dinoflagellates (5.7 +/- 0.48 and 6.9 +/- 0.66) (P. damicornis and H. actiniformis respectively; 95 confidence intervals). The ratio of acquired N to background N suggests that the added dissolved inorganic nitrogen (DIN) accounted for 50 to 100% of total nitrogen within the tissues of P. damicornis and H. actiniformis at the end of the experiment. The addition of the isotopically depleted nutrients (delta(15) N = 0parts per thousand) to patch reefs significantly decreased delta(15)N from control values of between 3 and 4 to values to below 1 in the case of all compartments, while delta(13)C values were relatively unresponsive to nutrient treatments. These findings suggest that coral delta(15)N has the potential to provide a historical record of the delta(15)N of dissolved nitrogen surrounding reef-building corals and their symbiotic dinoflagellates.
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Azo dyes are of environmental concern due to their degradation products, widespread use, and low-removal rate during conventional treatment. Their toxic properties are related to the nature and position of the substituents with respect to the aromatic rings and amino nitrogen atom. The dyes Disperse Red 1 and Disperse Red 13 were tested for Salmonella mutagenicity, cell viability by annexin V, and propidium iodide in HepG2 and by aquatic toxicity assays using daphnids. Both dyes tested positive in the Salmonella assay, and the suggestion was made that these compounds induce mainly frame-shift mutations and that the enzymes nitroreductase and O-acetyltransferase play an important role in the observed effect. In addition, it was shown that the presence of the chlorine substituent in Disperse Red 13 decreased the mutagenicity about 14 times when compared with Disperse Red 1, which shows the same structure as Disperse Red 13, but without the chlorine substituent. The presence of this substituent did not cause cytotoxicity in HepG2 cells, but toxicity to the water flea Daphnia similis increased in the presence of the chlorine substituent. These data suggest that the insertion of a chlorine substituent could be an alternative in the design of dyes with low-mutagenic potency, although the ecotoxicity should be carefully evaluated. (C) 2010 Wiley Periodicals, Inc. Environ Toxicol 26: 489-497, 2011.
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In this article we present a complete (1)H and (13)C NMR spectral analysis of three 7,7`-dihydroarylnaphthalene lignan lactones using modern NMR techniques such as COSY, HSQC, HMBC and NOE experiments. Complete assignment and homonuclear hydrogen coupling constant measurements were performed. Copyright (C) 2009 John Wiley & Sons, Ltd.
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Objective. The purpose of this study was to investigate the psychological symptoms experienced by recently widowed older men. It was hypothesized that conjugal bereavement in this group would be characterized by a mixture of depression, anxiety and loneliness. Design. Double cohort study. Setting. Suburban community population of Brisbane, Australia. Participants. Consecutive widowers (65+ years; N = 57) identified from official death records. Married men (65+ years; N = 57) identified from the electoral roll. Widowers interviewed at 6 weeks, 6 months and 13 months post-bereavement. Married men interviewed at similar intervals. Measures. Bereavement Phenomenology Questionnaire (BPQ), a 22-item self-report measure employing a four-point response scale to rate the frequency of phenomena over the previous fortnight. Zung Self-rating Depression Scale (SDS). State component of the Spielberger State/Trait Anxiety Inventory (STAI). Revised UCLA Loneliness Scale (ULS). 28-item General Health Questionnaire (GHQ). Results. Widowers reported more state anxiety and general psychological distress, but not more depression or loneliness, than matched married men over the first 13 months post-bereavement. Widowers also reported more sleep disturbance and thoughts of death and suicide than married men. Level of state anxiety was strongly correlated with intensity of grief, but not with age, income, education, occupational prestige, cognitive function, duration of wife's final illness or expectedness of wife's death. Conclusions. The main hypothesis was not supported, as anxiety symptoms were the predominant clinical feature of recent conjugal bereavement among older men. The nature of these anxiety symptoms requires further investigation in recently widowed older persons.
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A number of N- and C-based diastereomeric copper(II) complexes of the pendant-arm macrocyclic hexaamines trans- and cis-6,13-dimethyl-1,4,8,11-tetraazacyclotetradecane-6,13-diamine (L-1 and L-2) have been isolated and characterised. The crystal structures of the complexes RRSS-[CuL1(OH2)(2)][ClO4](2), SSRR-[Cu(H2L1)(OClO3)(2)]-[ClO4](2) . 2H(2)O RSRS-[CuL1(OClO3)]ClO4, RSRS-[CuL2(OClO3)]ClO4 and RRSS-[Cu(H2L2)(OClO3)(2)][ClO4](2) have been determined. Some unusual structural and spectroscopic variations are found across this series of diastereomers. The protonation constants of the pendant primary amines are dependent on the relative dispositions of the adjacent macrocyclic secondary amine H atoms, which is indicative of intramolecular hydrogen-bonding interactions.
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Changes in molecular motion in blends of PEO-PVPh have been studied using measurements of C-13 T-1 rho relaxation times. C-13 T-1 rho relaxation has been confirmed as arising from spin-lattice interactions by observation of the variation in T-1 rho with rf field strength and temperature. In the pure homopolymers a minimum in T-1 rho is observed at ca. 50 K above the glass transition temperatures detected by DSC. After blending, the temperature of the minimum in T-1 rho for PEO increased, while that for PVPh decreased, however, the minima, which correspond to the temperatures where the average correlation times for reorientation are close to 3.1 mu s, are separated by 45 K (in a 45% PEO-PVPh blend). These phenomena are explained in terms of the local nature of T-1 rho measurements. The motions of the individual homopolymer chains are only partially coupled in the blend. A short T-1 rho has been observed for protonated aromatic carbons, and assigned to phenyl rings undergoing large-angle oscillatory motion, The effects of blending, and temperature, on the proportion of rings undergoing oscillatory motion are analyzed.
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Airway epithelium plays important roles in the pathophysiology of asthma. Creatine supplementation (Cr) was shown to increase asthma features in a murine model of allergic asthma; however, the role of the airway epithelium in this inflammatory response is not known. BALB/c mice were divided into control, creatine supplementation, ovalbumin-sensitized (OVA) and OVA plus creatine supplementation groups. OVA sensitization occurred on days 0, 14, 28 and 42, and ovalbumin challenge from days 21-53. Cr was also given on days 21-53. Total and differential cells counts in BALF were evaluated. Quantitative epithelial expression of interleukin (IL)-4, IL-5, IL-13, CCL11, CCL5, CCL2, iNOS, VCAM-1, ICAM-1, NF-kappa B, VEGF, TGF-beta, IGF-1, EGFR, TIMP-1, TIMP-2, MMP-9, MMP-12 and arginase II were performed. Cr increased the number of total cells and eosinophils in BALF, the epithelial content of goblet cells and the epithelial expression of IL-5, CCL2, iNOS, ICAM-1, NF-kappa B, TGF-beta, TIMP-1 and MMP-9 when compared to the control group (p < 0.05). Creatine supplementation also exacerbated goblet cell proliferation, and IL-5 and iNOS expression by epithelial cells compared to the OVA group (p < 0.01). Creatine up-regulates the pro-inflammatory cascade and remodelling process in this asthma model by modulating the expression of inflammatory mediators by epithelial cells.
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The reactions between novolac resins and hexamethylenetetramine (HMTA) which occur on curing have been studied by C-13 and N-15 high-resolution n.m.r. in both solution and the solid state. Strong evidence for the existence of many curing intermediates is obtained. New curing intermediates are reported along with experimental data to support previously postulated intermediates. The initial curing reactions between novolac and HMTA produce various substituted benzoxazines and benzylamines. Thermal decomposition/oxidation and further reactions of these initial intermediates generate methylene linkages between phenolic rings for chain extension and cross-linking. Among the three kinds of methylene linkages, the para-para methylene linkages are formed at relatively lower temperatures. Various imine, amide and imide side-products also concurrently appear during the process. The initial amount of HMTA plays a critical role in the curing reactivity and chemical structures of the cured resins. The lower the amount of HMTA, the lower the temperature at which curing occurs, and the lower the amount of the nitrogen-containing side-products in the finally cured resins. The ortho-linked intermediates are relatively stable, and can remain in the cured resins up to higher temperatures. The study provides an extensive description of the curing reactions of novolac resins. (C) 1997 Elsevier Science Ltd.
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Background: The thyroid transcription factor-1 (TTF-1) is a tissue-specific transcription factor that Could playan important role in cell differentiation and morphogenesis of lung tumors. Matrix metalloproteinase-9 (MMP-9) is a protease commonly expressed in non-small cell lung cancer, conferring angiogenic and metastatic potential. Methods: We assessed TTF-1 and MMP-9 tumor expression by immunohistochemistry in 51 patients with lung adenocarcinoma, stage 11113 or IV, treated with platinum regimens. A bicategorical prognostic model was obtained using the Kaplan-Meier method, COX regression, and conjunctive consolidation. Results: The median expression of TTF-1 was 30.0% (range: 0-85.9%). All tumors expressed MMP-9 (median: 78.7%: range: 15.2-96.1%). Median survival was 41.6 weeks, with estimated 1- and 2-year survival rates of 45.0% and 22.0%, respectively. Poor performance status (Karnofsky scale) - hazards ratio(HR): 1.03. 95% confidence interval (CI): 1.01-1.06: low TTF-1 expression (<40%) - FIR: 4.00, 95% CI: 1.75-9.09: and high MMP-9 expression (>= 80%) - HR: 2.82, 95% CI: 1.30-6.08 were independent prognostic factors. Patients could be stratified in three death risk groups according to markers expression: low risk (high TTF-1 and low MMP-9; median survival: 127.6 weeks), intermediate risk (low TTF-1 OF high MMP-9; median survival: 39.0 weeks): and high risk (low TTF-1 and high MMP-9: median survival: 16.4 weeks). Conclusion: TTF-1 and MMP-9 tumor expression as detected by immunohistochemistry may allow identification of different, clinically meaningful, prognostic groups of advanced lung adenocarcinoma patients treated with platinum regimens. (C) 2008 Elsevier Ireland Ltd. All rights reserved.
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Background: Few studies have addressed small airway (SA) histopathological changes and their possible role in the remodeling process in idiopathic interstitial pneumonias. Objectives: To study morphological, morphometrical and immunohistochemical features of SA in idiopathic pulmonary fibrosis (usual interstitial pneumonia, UIP) and nonspecific interstitial pneumonia (NSIP). Methods: We analyzed SA pathology in lung biopsies from 29 patients with UIP and 8 with NSIP. Biopsies were compared with lung tissue from 13 patients with constrictive bronchiolitis (CB) as positive controls and 10 normal autopsied control lungs. We semi-quantitatively analyzed SA structure, inflammation, architectural features and the bronchiolar epithelial immunohistochemical expression of TGF-beta, MMP-2, 7, 9, and their tissue inhibitors (TIMP-1, 2). Results: Compared to controls, patients with UIP, NSIP and CB presented increased bronchiolar inflammation, peribronchiolar inflammation and fibrosis and decreased luminal areas. UIP patients had thicker walls due to an increase in most airway compartments. NSIP patients presented increased epithelial areas, whereas patients with CB had larger inner wall areas. All of the groups studied presented increased bronchiolar expression of MMP-7 and MMP-9, compared to the controls. Conclusion: We conclude that SAs are pathologically altered and may take part in the lung-remodeling process in idiopathic interstitial pneumonias. Copyright (C) 2009 S. Karger AG, Basel
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Objective To determine normal blood flow velocities across the fetal tricuspid valve (TV) at 11-13 weeks and 6 days of gestation and to examine the reproducibility of these measurements. Methods A prospective study involving 166 normal singleton pregnancies examined at 11-13 weeks and 6 days was carried out. Descriptive analysis of E- and A-waves` maximum velocities, E/A ratio, duration of the cardiac cycle (C) and diastole (D) and D/C ratio were calculated. Intraobserver and interobserver agreement analysis was performed in a subgroup of 12 cases. Results Average (+/- SD) flow velocities were: E-wave, 25.0 (+/- 4.6) cm/s; A-wave. 42.9 (+/- 5.9) cm/s; E/A, 0.58 (+/- 0.07); cardiac cycle, 390 (+/- 21.1) ms; diastole, 147 (+/- 18) ms and D/C, 0.38 (+/- 0.04). Significant correlation was observed between all parameters (except A-wave) and gestational age but not with nuchal translucency (NT). Intraclass correlation coefficients (interobserver, intraobsever examiner I and intraobserver examiner 2) were: E-wave, 0.53, 0.53 and 0.64; A-wave, 0.45, 0.46 and 0.49; cardiac cycle, 0.70, 0.79 and 0.84 and diastole, 0.63, 0.85 and 0.82, respectively. Conclusions The present study establishes normal Doppler parameters for blood flow across the TV at 11 - 13 weeks and 6 days and demonstrates that these parameters do not correlate with NT measurement and have good/moderate reproducibility. Copyright (C) 2010 John Wiley & Sons, Ltd.
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Double aneuploidy, (48,XXY,+21) of maternal origin in a child born to a 13-year-old mother: evoluation of the maternal folate metabolism: The occurrence of non-mosaic double trisomy is exceptional in newborns. In this paper, a 48,XXY,+21 child, the parental origin of the extra chromosomes and the evaluation of the maternal folate metabolism are presented. The infant was born to a 13-year-old mother and presented with the typical clinical features of Down syndrome (DS). The origin of the additional chromosomes was maternal and most likely resulted from errors during the first meiotic division. Molecular analysis of 12 genetic polymorphisms involved in the folate metabolism revealed that the mother is heterozygous for the MTHFR C677T and TC2 A67G polymorphisms, and homozygous for the mutant MTRR A66G polymorphism. The maternal homocysteine concentration was 4.7 mu mol/L, a value close to the one considered as a risk factor for DS in our previous study. Plasma methylmalonic acid and serum folate concentrations were 0.17 mu mol/L and 18.4 ng/mL, respectively. It is possible that the presence of allelic variants for the folate metabolism and Hey concentration might have favored errors in chromosomal disjunction (hiring gametogenesis in this young mother. To our knowledge, this is the first patient with non-mosaic Down-Klinefelter born to a teenage mother, resulting from a rare fertilization event combining an abnormal 25,XX,+21 oocyte and a 23,Y spermatozoon.
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Altered activity of matrix metalloproteinases (MMPs) is implicated in the vascular remodeling of hypertension. We examined whether increased MMP-2 expression/activity plays a role in the vascular remodeling and dysfunction found in the two-kidney, one-clip (2K-1C) hypertension. Sham operated or 2K-1C hypertension rats were treated with doxycycline 30 mg/(kg day) (or vehicle). Systolic blood pressure was monitored weekly. After 8 weeks of treatment, aortic rings were isolated to assess endothelium-dependent and independent relaxations. Quantitative morphometry of structural changes, collagen, and elastin contents in the aortic wall were studied in hematoxylin/eosin, Sirius Red, and Orceine stained aortic sections, respectively. Aortic MMP-2 levels were determined by gelatin zymography and aortic MMP-2 proteolytic activity was measured using DQ gelatin as the substrate after MMP-2 was captured by a specific antibody and immobilized on a microplate. Aortic MMP-2/tissue inhibitor of metalloprotemases (TIMP)-2 mRNA levels were determined by real time RT-PCR. Doxycycline attenuated 2K-1C hypertension (215 +/- 8 mmHg versus 167 +/- 13 mmHg in 2K-1C rats and 2K-1C + doxy rats, respectively; P < 0.01) and prevented the 35% reduction in endothelium-dependent vasorelaxation found in 2K-1C rats. Doxycycline prevented the increases in media thickness, and was associated with lower media/lumen and cross-sectional areas (all P<0.01). Doxycycline also prevented excessive collagen and elastin deposition in the vascular wall. Increased MMP-2 and Pro-MMP-2 levels and MMP-2 activity were found in the aortas of 2K-1C rats (all P<0.05). A 21-fold increase (P<0.001) in the ratio of MMP-2/TIMP-2 mRNA expression was found in the 2K-1C group, whereas this ratio remained unaltered in 2K-1C+doxy rats. Our results suggest that MMP-2 plays a role in 2K-1C hypertension and its structural and functional vascular changes, which were attenuated by doxycycline. (C) 2007 Elsevier Ireland Ltd. All rights reserved.