Presence of Oil Mineral Aggregates (OMAs) in Surface Sediments from Mexico’s Exclusive Economic Zone,NW Gulf of Mexico

We assessed the presence and distribution of oil mineral aggregates (OMAs) in surficial sediments of Mexican waters in the NW Gulf of Mexico, their potential sources and their correlation with polycyclic aromatic hydrocarbons (PAH). In summer of 2010, OMAs were detected in three shallow sites. In winter of 2011, OMAs were observed in ten sites, two of them in the northernmost area at >?1500 m depth. These particles were possibly advected from the north Gulf and Mississippi area following the deep-water currents of the zone. The OMAs from shallower sites may reflect local pollution sources. PAHs displayed low concentrations in both surveys (from 0.01 to 0.7 µg g^?1 in summer, and from 0.01 to 0.51 µg g^?1 in winter), and showed rather a local origin. The expansion of the oil and port industry in the region is accountable for most of the OMAs detected.     

Psychological and Emotional Impact of COVID-19 Pandemic on People Living with Chronic Disease: HIV and Cancer

AIDS and Behavior - People living with chronic disease (PLWCD) are the frailest category, both for the risk of severe COVID-19 illness and for the impact on the care continuum. Aim of this study...     

Extraction of artefactual MRS patterns from a large database using non-negative matrix factorization

Despite the success of automated pattern recognition methods in problems of human brain tumor diagnostic classification, limited attention has been paid to the issue of automated data quality assessment in the field of MRS for neuro-oncology. Beyond some early attempts to address this issue, the current standard in practice is MRS quality control through human (expert-based) assessment. One aspect of automatic quality control is the problem of detecting artefacts in MRS data. Artefacts, whose variety has already been reviewed in some detail and some of which may even escape human quality control, have a negative influence in pattern recognition methods attempting to assist tumor characterization. The automatic detection of MRS artefacts should be beneficial for radiology as it guarantees more reliable tumor characterizations, as well as the development of more robust pattern recognition-based tumor classifiers and more trustable MRS data processing and analysis pipelines. Feature extraction methods have previously been used to help distinguishing between good and bad quality spectra to apply subsequent supervised pattern recognition techniques. In this study, we apply feature extraction differently and use a variant of a method for blind source separation, namely Convex Non-Negative Matrix Factorization, to unveil MRS signal sources in a completely unsupervised way. We hypothesize that, while most sources will correspond to the different tumor patterns, some of them will reflect signal artefacts. The experimental work reported in this paper, analyzing a combined short and long echo time ¹H-MRS database of more than 2000 spectra acquired at 1.5T and corresponding to different tumor types and other anomalous masses, provides a first proof of concept that points to the possible validity of this approach.     

Chronic total occlusion:To treat or not to treat

Over the last two decades,there has been increasing interest in new techniques for the percutaneous treatment of coronary chronic total occlusions(CTO),which have a success rate that is much higher than that of a few years ago.The rise in percutaneous treatment for these lesions is due to its ability to improve the symptoms and prognosis of patients in the chronic and stable phase of coronary disease.Current data suggest that successful percutaneous coronary intervention for CTO is associated with improvement in patient symptoms,quality of life,left ventricular function,and survival,compared with those with unsuccessful CTO PCI.However,all the scientific evidence supporting this treatment comes from observational studies,and no randomized study comparing percutaneous treatment with medical treatment has yet been published.A major limitation of these studies is their observational design,with limited information with regard to potential baseline differences between the successful vs unsuccessful cohorts.Pending randomized studies,patients should be selected very carefully,especially if they are asymptomatic or very few symptoms,and the benefits obtained in terms of complications during the procedure,the quality of life obtained and further ischemic events avoided should be evaluated systematically.In this review,we will consider the available information supporting percutaneous treatment for chronic occlusions,as well as the areas of uncertainty where more research projects are required.     

When is injury potentially reversible in a lung ischemia–reperfusion model?

ObjectiveTo verify the impact of ischemic time on lung cell viability in an experimental model of lung ischemia–reperfusion (IR) injury and its repercussion on lung performance after reperfusion.MethodsTwenty-four animals were subjected to selective clamping of the left pulmonary artery and divided into four groups (n = 6) according to ischemic time: 15 (IR15), 30 (IR30), 45 (IR45), and 60 min (IR60). All animals were observed for 120 min after reperfusion. The hemodynamics, arterial blood gases measurements, and histologic changes were analyzed. Immunofluorescence assays for caspase 3 and annexin V were performed. Lipid peroxidation was assessed by thiobarbituric acid–reactive substances, and caspase 3 activity was assessed by colorimetric extract.ResultsThe partial pressure of arterial oxygen significantly decreased at the end of the observation period in the IR30, IR45, and IR60 groups (P < 0.05). The final mean arterial pressure significantly decreased in the IR60 group (P < 0.05). We observed a significant increase in caspase 3 activity and caspase 3–positive cells by immunofluorescence in the IR45 group compared with the other groups (P < 0.05). Additionally, there was an increase in necrotic cells assessed by annexin V in the IR60 group. The histologic score did not show differences among the different groups.ConclusionsThe degree of cell damage had a negative impact on lung performance. Sixty minutes of lung ischemia and posterior reperfusion resulted in an increased number of necrotic cells, suggesting that these cells may not be able to reverse the effects of the IR injury because of the lack of viable cells.