32 research outputs found
Herramientas normativas sobre la compleja realidad ambiental : sus generalidades
p.1-5El presente trabajo tiene como objetivo de sistematizar el proceso de las herramientas jurÃdicas básicas sobre el medio ambiente ya que, es de fundamental importancia el conocimiento normativo que va a regular las relaciones sociales para que, desde una perspectiva holÃstica se puedan lograr resoluciones integrales. El derecho ambiental es la respuesta normativa a la creciente degradación que sugre el medio en que vivimos. Se integra con una serie de normas de diverso nivel de importancia (leyes, decretos, ordenazas, resoluciones, etc.) y diverso origen (demanadas del estado nacional, de los estados provinciales o de los municipios), que en algunos casos se superponen y en otros se contradicen. Con una visión interdisciplinaria y en la necesidad de tomar cnocimiento del derecho ambiental y poder identificar, cuál serÃa la normativa aplicable a una determinada organización/actividad, en una primera instancia y a modo de guÃa se han elaborado una serie de preguantas esenciales que pueden resultar de gran utilidad para que, la gestión ambiental de los profesionales en su hacer se ajuste a derecho
Coronary plaque composition influences biomechanical stress and predicts plaque rupture in a morpho-mechanic OCT analysis
Plaque rupture occurs if stress within coronary lesions exceeds the protection exerted by the fibrous cap overlying the necrotic lipid core. However, very little is known about the biomechanical stress exerting this disrupting force. Employing optical coherence tomography (OCT), we generated plaque models and performed finite-element analysis to simulate stress distributions within the vessel wall in 10 ruptured and 10 non-ruptured lesions. In ruptured lesions, maximal stress within fibrous cap (peak cap stress [PCS]: 174 ± 67 vs. 52 ± 42 kPa, p<0.001) and vessel wall (maximal plaque stress [MPS]: 399 ± 233 vs. 90 ± 95 kPa, p=0.001) were significantly higher compared to non-ruptured plaques. Ruptures arose in the immediate proximity of maximal stress concentrations (angular distances: 21.8 ± 30.3° for PCS vs. 20.7 ± 23.7° for MPS); stress concentrations excellently predicted plaque rupture (area under the curve: 0.940 for PCS, 0.950 for MPS). This prediction of plaque rupture was superior to established vulnerability features such as fibrous cap thickness or macrophage infiltration. In conclusion, OCT-based finite-element analysis effectively assesses plaque biomechanics, which in turn predicts plaque rupture in patients. This highlights the importance of morpho-mechanic analysis assessing the disrupting effects of plaque stress
Colocalization of plaque macrophages and calcification in coronary plaques as detected by optical coherence tomography predicts cardiovascular outcome
Mannose as a biomarker of coronary artery disease: Angiographic evidence and clinical significance
Background
High mannose has previously associated with insulin resistance and cardiovascular disease (CVD). Our objective is to establish whether mannose is associated with anatomical evidence of coronary artery disease (CAD).
Methods
Plasma mannose concentrations were measured by liquid chromatography/tandem mass spectrometry in a discovery cohort (n = 513) and a validation cohort (n = 221) of carefully phenotyped individuals. In both cohorts CAD was quantitated using state-of-the-art imaging techniques (coronary computed coronary tomography angiography (CCTA), invasive coronary angiography and optical coherence tomography). Information on subsequent CVD events/death was collected. Associations of mannose with angiographic variables and biomarkers were tested using univariate and multivariate regression models. Survival analysis was performed using the Kaplan-Meier estimator.
Results
Mannose was related to indices of CAD and features of plaque vulnerability. In the discovery cohort, mannose was a marker of quantity and quality of CCTA-proven CAD and subjects with a mannose level in the top quartile had a significantly higher risk of CVD events/death (p = 3.6e-5). In the validation cohort, mannose was significantly associated with fibrous cap thickness < 65 \u3bcm (odds ratio = 1.32 per each 10 \u3bcmol/L mannose change [95% confidence interval, 1.05\u20131.65]) and was an independent predictor of death (hazard ratio for mannose 65vs < 84.6 \u3bcmol/L: 4.0(95%CI, 1.4\u201311.3), p = 0.006)
Bosniak classification of renal cystic lesions according to multidetector computed tomography findings
Diabetes mellitus Typ 2 und koronare Kalzifizierungen - eine Studie mittels optischer Kohärenztomographie bei Patienten mit stabiler koronarer Herzerkrankung
Patients with type 2 diabetes mellitus (T2DM) present a higher risk for acute coronary syndrome (ACS) compared to patients without T2DM. As most of these ACS are pathophysiologically caused by the rupture of a coronary plaque, in the last years researchers focused on predictors for coronary plaque instability, which may then evolve in plaque rupture. A thinner fibrous cap over the necrotic lipid core is, for instance, an established feature of plaque vulnerability and can be visualized and quantified in vivo through optical coherence tomography (OCT), an intravascular imaging technique. However, it has been recently discussed whether localization, size, shape or extent of coronary calcification play a role in plaque instability. In fact, various imaging studies supported this hypothesis by showing a higher incidence of spotty calcifications in lesions of patients with ACS compared to patients with stable coronary artery disease. However, data regarding differences in localization, size, shape or extent of calcification between patients with and without T2DM are currently lacking. Our hypothesis was that these newly suggested features of plaque vulnerability may add to the well-known vulnerable phenotype of coronary plaques in patients with T2DM.We therefore analyzed through OCT lesions of patients with and without T2DM with stable coronary artery disease. In this group we performed a pre-procedural OCT, where we analyzed the localization, size, shape or extent of coronary calcification in addition to the established parameters of plaque vulnerability. We could show that patients with T2DM present a lower minimal fibrous cap thickness (FCT) as well as a higher percent stenosis compared to patients without T2DM. On the contrary, we could not detect any significant difference in localization, size, shape or extent of intravascular calcification in the two groups. In the light of these data, the role of established features of plaque vulnerability - in particular FCT - could be confirmed as marker of the higher cardiovascular risk of patients with coronary artery disease and T2DM. On the contrary, the localization, size, shape or extent of coronary calcification does not seem to influence the higher risk of diabetic patients compared to patients without T2DM