Calibration of myocardial T2 and T1 against iron concentration.

BACKGROUND: The assessment of myocardial iron using T2* cardiovascular magnetic resonance (CMR) has been validated and calibrated, and is in clinical use. However, there is very limited data assessing the relaxation parameters T1 and T2 for measurement of human myocardial iron. METHODS: Twelve hearts were examined from transfusion-dependent patients: 11 with end-stage heart failure, either following death (n=7) or cardiac transplantation (n=4), and 1 heart from a patient who died from a stroke with no cardiac iron loading. Ex-vivo R1 and R2 measurements (R1=1/T1 and R2=1/T2) at 1.5 Tesla were compared with myocardial iron concentration measured using inductively coupled plasma atomic emission spectroscopy. RESULTS: From a single myocardial slice in formalin which was repeatedly examined, a modest decrease in T2 was observed with time, from mean (± SD) 23.7 ± 0.93 ms at baseline (13 days after death and formalin fixation) to 18.5 ± 1.41 ms at day 566 (p<0.001). Raw T2 values were therefore adjusted to correct for this fall over time. Myocardial R2 was correlated with iron concentration [Fe] (R2 0.566, p<0.001), but the correlation was stronger between LnR2 and Ln[Fe] (R2 0.790, p<0.001). The relation was [Fe] = 5081•(T2)-2.22 between T2 (ms) and myocardial iron (mg/g dry weight). Analysis of T1 proved challenging with a dichotomous distribution of T1, with very short T1 (mean 72.3 ± 25.8 ms) that was independent of iron concentration in all hearts stored in formalin for greater than 12 months. In the remaining hearts stored for <10 weeks prior to scanning, LnR1 and iron concentration were correlated but with marked scatter (R2 0.517, p<0.001). A linear relationship was present between T1 and T2 in the hearts stored for a short period (R2 0.657, p<0.001). CONCLUSION: Myocardial T2 correlates well with myocardial iron concentration, which raises the possibility that T2 may provide additive information to T2* for patients with myocardial siderosis. However, ex-vivo T1 measurements are less reliable due to the severe chemical effects of formalin on T1 shortening, and therefore T1 calibration may only be practical from in-vivo human studies

Assessing the Effectiveness of a Performance Evaluation System in the Public Health Care Sector: Some Novel Evidence from the Tuscany Region Experience

Since 80's the introduction of New Public Management principles has promoted the use of performance measurement to drive a more efficient, effective and accountable public sector. The adoption of a sophisticated and comprehensive multidimensional performance measurement system, which looks beyond traditional financial measures, based on organization strategies, such as the balanced scorecard, has thus been suggested. This revolution in the public management came together with the devolution processes that involved most European public health systems. Set within this context, in the last decade, each of the twenty Italian regions developed its own management tools. Among others, the Tuscan performance evaluation system (PES) has been valued as a particularly innovative and comprehensive system. This paper reports the novel experience of the Tuscan PES; in particular, it measures PES effectiveness and discusses the critical factors that could have led to the PES success. Five are the critical success factors identified by researchers: the visual reporting system, the linkage between PES and CEO's reward system, the public disclosure of data, the high level of employees and managers involvement into the entire process and the strong political commitment. All those factors run together to achieve better results; however, the process of development of the system plays a pivotal role. Scholars suggest the use of a constructive approach in order to gain effective changes in human organization. According to this stream of literature, this paper contributes by the novel experience of the Tuscan PES in addressing as a further fruitful application of the constructivist approach in healthcare

Effects of Perfluorocarbons on surfactant exocytosis and membrane properties in isolated alveolar type II cells

<p>Abstract</p> <p>Background</p> <p>Perfluorocarbons (PFC) are used to improve gas exchange in diseased lungs. PFC have been shown to affect various cell types. Thus, effects on alveolar type II (ATII) cells and surfactant metabolism can be expected, data, however, are controversial.</p> <p>Objective</p> <p>The study was performed to test two hypotheses: (I) the effects of PFC on surfactant exocytosis depend on their respective vapor pressures; (II) different pathways of surfactant exocytosis are affected differently by PFC.</p> <p>Methods</p> <p>Isolated ATII cells were exposed to two PFC with different vapor pressures and spontaneous surfactant exocytosis was measured. Furthermore, surfactant exocytosis was stimulated by either ATP, PMA or Ionomycin. The effects of PFC on cell morphology, cellular viability, endocytosis, membrane permeability and fluidity were determined.</p> <p>Results</p> <p>The spontaneous exocytosis was reduced by PFC, however, the ATP and PMA stimulated exocytosis was slightly increased by PFC with high vapor pressure. In contrast, Ionomycin-induced exocytosis was decreased by PFC with low vapor pressure. Cellular uptake of FM 1-43 - a marker of membrane integrity - was increased. However, membrane fluidity, endocytosis and viability were not affected by PFC incubation.</p> <p>Conclusions</p> <p>We conclude that PFC effects can be explained by modest, unspecific interactions with the plasma membrane rather than by specific interactions with intracellular targets.</p

An overview of concepts and approaches used in estimating the burden of congenital disorders globally.

Congenital disorders are an important cause of pregnancy loss, premature death and life-long disability. A range of interventions can greatly reduce their burden, but the absence of local epidemiological data on their prevalence and the impact of interventions impede policy and service development in many countries. In an attempt to overcome these deficiencies, we have developed a tool-The Modell Global Database of Congenital Disorders (MGDb) that combines general biological principles and available observational data with demographic data, to generate estimates of the birth prevalence and effects of interventions on mortality and disability due to congenital disorders. MGDb aims to support policy development by generating country, regional and global epidemiological estimates. Here we provide an overview of the concepts and methodological approach used to develop MGDb

Sleep and circadian rhythms in mood disorders

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65629/1/j.1600-0447.2007.00968.x.pd

Correction to: Clinical recommendations for cardiovascular magnetic resonance mapping of T1, T2, T2* and extracellular volume: A consensus statement by the Society for Cardiovascular Magnetic Resonance (SCMR) endorsed by the European Association for Cardiovascular Imaging (EACVI).

CORRECTION TO: J CARDIOVASC MAGN RESON (2017) 19: 75. DOI: 10.1186/S12968-017-0389-8: In the original publication of this article [1] the "Competing interests" section was incorrect. The original publication stated the following competing interests