Spectrally selective B1-insensitive T2 magnetization preparation sequence.

A T(2) magnetization-preparation (T(2) Prep) sequence is proposed that is insensitive to B(1) field variations and simultaneously provides fat suppression without any further increase in specific absorption rate (SAR). Increased B(1) inhomogeneity at higher magnetic field strength (B(0) > or = 3T) necessitates a preparation sequence that is less sensitive to B(1) variations. For the proposed technique, T(2) weighting in the image is achieved using a segmented B(1)-insensitive rotation (BIR-4) adiabatic pulse by inserting two equally long delays, one after the initial reverse adiabatic half passage (AHP), and the other before the final AHP segment of a BIR-4 pulse. This sequence yields T(2) weighting with both B(1) and B(0) insensitivity. To simultaneously suppress fat signal (at the cost of B(0) insensitivity), the second delay is prolonged so that fat accumulates additional phase due to its chemical shift. Numerical simulations as well as phantom and in vivo image acquisitions were performed to show the efficacy of the proposed technique.

Las narrativas del trabajo (versión 0.2)

Este texto recrea en forma de juego la idea de que la mujer se encuentra en un continuo de vida-trabajo. No existe "el ángel del hogar" y, por lo tanto, no hay representación de las tareas domésticas, pero éstas son un continuo que estructuran la vida de "b", ya que exigen un constante cuidado y orden. La teórica independencia de la mujer respecto a lo doméstico y el ser autónoma le han hecho adoptar el trabajo como forma de vida. Esta contribución cuestiona el concepto de trabajo y pone en evidencia las carencias de los términos "flexibilidad", "autonomía", "individualidad", etc.

Mico-cocktail validation for CYP3A and CYP2D6 assessment using a low dose of midazolam (0.075 mg) and dextromethorphan (2.5 mg)

Background/Aim: Cocktail approach is generally preferred to individual administration of probes in order to characterize the activity of multiple enzymes. However, cocktail strategy has several drawbacks such as drug-drug interactions, tolerability and toxicity. Hence, there is a need to develop cocktails using low doses of probes. Our aim was to investigate whether the simultaneous oral administration of microdoses of midazolam (MDZ) and dextromethorphan (DEM) can be used to assess the simultaneous activities of CYP3A and CYP2D6. Methods: As part of a 5 arm randomized cross-over control trial on the analgesic efficacy of oxycodone, ten healthy young non-smoking males received the following combinations of drugs: Quinidine (Q)+ ketoconazole (K) or Q+placebo (P) or K+P or P+P. In all cases MDZ (0.075 mg) and DEM (2.5 mg) were administrated 1 hour after Q, K or P. CYP2D6 and CYP3A activities were determined after urine collection during 8 hours (ratio DEM/DOR), and a blood sample (EDTA) after 30 min (ratio 1-OH-MDZ/MDZ). DEM and DOR analysis was performed using LC-fluorescence. MDZ and 1-OH-MDZ determination was performed using GC-MS. Allele's variants of CYP2D6 were detected using the AmpliChipTMCYP450 (Roche). Results: CYP2D6 genotype predicted 1 poor (PM), 1 intermediate (IM), 7 extensive (EM) and 2 ultra rapid (UM) metabolizers. A good correlation was obtained between the predicted and the measured phenotypes except for 1 EM phenotyped as UM. Two duplications for alleles *41/*41xN and *1/*2xN were detected and the two volunteers were phenotyped as UM. A potent inhibition of CYP2D6 or CYP3A4 was obtained when Q or K were used. Mean metabolic ratio DEM/DOR in P and K groups were 0.015 (±0.028) and 0.015 (±0.019). It significantly increased in Q and QK groups (0.668 (±0.676) and 0.743 (±1.038)). Mean 1-OH-MDZ/MDZ in P, Q were 2.73 (±1.05) and 2.55 (±1.40) while it significantly decreased in K and QK groups (0.11 (±0.05), 0.10 (±0.05)). Moreover, there were no statistically significant differences between QK and K sessions for CYP3A and between QK and Q for CYP2D6 which indicate that there is no interaction between the two metabolic pathways. Conclusion: Simultaneous assessment of CYP3A and CYP2D6 activities can be obtained by low oral doses (micro-cocktail) of MDZ and DEM. Specific inhibitors such as Q or K modulates selectively CYP2D6 or CYP3A activities.

[Voyage en Italie : 1824-1830]. , Bains publics. Sur une Echelle de 0,05 P.M. : [plan d'ensemble] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 377

[Voyage en Italie : 1824-1830]. , Maison de l'Auteur Tragique. 0,005 P.M. : [plan] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 404

[Voyage en Italie : 1824-1830]. , Maison de Salluste. Sur une Echelle de 0,005 P.M. : [plan d'ensemble] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 407

Os museus portugueses e a Web 2.0

O presente artigo dá a conhecer um projecto de investigação que teve como objectivo determinar e analisar a partir da observação dos sítios Web dos museus portugueses quais as ferramentas Web 2.0 usadas por estas instituições no desenvolvimento das suas actividades. Neste sentido, foram seleccionados como amostra os 125 museus pertencentes à Rede Portuguesa de Museus. Os resultados obtidos permitem-nos afirmar que utilização das ferramentas Web 2.0 por parte dos museus portugueses analisados está numa fase inicial. A ferramenta mais usada é o blogue. Foram, também, identificados projectos pioneiros ao nível dos wikis, Licenças Creative Commons, Youtube, Flickr e redes sociais on-line.

[Voyage en Italie : 1824-1830]. , Arc de Gallien. Sur une Echelle de 0,010 P.M. : [élévation, plan, coupe] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 491

[Voyage en Italie : 1824-1830]. , Portique connu sous le nom de Bains de Paul Emile. Sur une Echelle de 0,10 P.M. : [coupe, deux élévation principale et latérale partielles, quatre plans, détail d'une pierre] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 597

[Voyage en Italie : 1824-1830]. , Cour du Palais de Venise, à Rome. Sur une Echelle de 0,010 P.M. : [élévation avec coupe sur une galerie] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 582

[Voyage en Italie : 1824-1830]. , Palais de Venise. Croisée du 1er Etage. Sur une Echelle de 0,050 P.M. : [élévation et coupe d'une fenêtre] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 585

[Voyage en Italie : 1824-1830]. , Tombeau de Bibulus à Rome. Sur une Echelle de 0,025 P.M. : [élévation, plan partiel] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 607

Measuring brain perfusion with intravoxel incoherent motion (IVIM): Initial clinical experience.

PURPOSE: To evaluate the feasibility of intravoxel incoherent motion (IVIM) perfusion measurements in the brain with currently available imaging systems. MATERIALS AND METHODS: We acquired high in-plane resolution (1.2 × 1.2 mm(2) ) diffusion-weighted images with 16 different values of b ranging from 0 to 900 s/mm(2) , in three orthogonal directions, on 3T systems with a 32-multichannel receiver head coil. IVIM perfusion maps were extracted by fitting a double exponential model of signal amplitude decay. Regions of interest were drawn in pathological and control regions, where IVIM perfusion parameters were compared to the corresponding dynamic susceptibility contrast (DSC) parameters. RESULTS: Hyperperfusion was found in the nonnecrotic or cystic part of two histologically proven glioblastoma multiforme and in two histologically proven glioma WHO grade III, as well as in a brain metastasis of lung adenocarcinoma, in a large meningioma, and in a case of ictal hyperperfusion. A monoexponential decay was found in a territory of acute ischemia, as well as in the necrotic part of a glioblastoma. The IVIM perfusion fraction f correlated well with DSC CBV. CONCLUSION: Our initial report suggests that high-resolution brain perfusion imaging is feasible with IVIM in the current clinical setting. J. Magn. Reson. Imaging 2014;39:624-632. © 2013 Wiley Periodicals, Inc.

Pulmonary thrombembolism as cause of death on unenhanced postmortem 3T MRI.

OBJECTIVES: To investigate unenhanced postmortem 3-T MR imaging (pmMRI) for the detection of pulmonary thrombembolism (PTE) as cause of death. METHODS: In eight forensic cases dying from a possible cardiac cause but with homogeneous myocardium at cardiac pmMRI, additional T2w imaging of the pulmonary artery was performed before forensic autopsy. Imaging was carried out on a 3-T MR system in the axial and main pulmonary artery adapted oblique orientation in situ. In three cases axial T2w pmMRI of the lower legs was added. Validation of imaging findings was performed during forensic autopsy. RESULTS: All eight cases showed homogeneous material of intermediate signal intensity within the main pulmonary artery and/or pulmonary artery branches. Autopsy confirmed the MR findings as pulmonary artery thrombembolism. At lower leg imaging unilateral dilated veins and subcutaneous oedema with or without homogeneous material of intermediate signal intensity within the popliteal vein were found. CONCLUSIONS: Unenhanced pmMRI demonstrates pulmonary thrombembolism in situ. PmMR may serve as an alternative to clinical autopsy, especially when consent cannot be obtained. KEY POINTS: ? Postmortem MRI (pmMRI) provides an alternative to clinical autopsy ? Fatal pulmonary thrombembolism (PTE) can now be diagnosed using postmortem MRI (pmMRI). ? Special attention has to be drawn to the differentiation of postmortem clots.