Objective:We compared the ability of arterial spin labeling (ASL), an MRI method that measures cerebral blood flow (CBF), to that of FDG-PET in distinguishing patients with Alzheimer disease (AD) from healthy, age-matched controls.Methods: Fifteen patients with AD (mean age 72 Ϯ 6 years, Mini-Mental State Examination score[MMSE] 20 Ϯ 6) and 19 age-matched controls (mean age 68 Ϯ 6 years, MMSE 29 Ϯ 1) underwent structural MRI. Participants were injected with 5 mCi of FDG during pseudocontinuous ASL scan, which was followed by PET scanning. Statistical parametric mapping and regions of interest (ROI) analysis were used to compare the ability of the 2 modalities in distinguishing patients from controls. Similarity between the 2 modalities was further assessed with linear correlation maps of CBF and metabolism to neuropsychological test scores. Results:Good agreement between hypoperfusion and hypometabolism patterns was observed, with overlap primarily in bilateral angular gyri and posterior cingulate. ROI results showed similar scales of functional deficit between patients and controls in both modalities. Both ASL and FDG-PET were able to distinguish neural networks associated with different neuropsychological tests with good overlap between modalities. Conclusions:

BACKGROUND The utility flourodeoxyglucose PET (FDG-PET) imaging in Alzheimer’s Disease (AD) diagnosis is well established. Recently, measurement of cerebral blood flow using arterial spin labeling MRI (ASL-MRI) has shown diagnostic potential in AD, though it has never been directly compared to FDG-PET. METHODS We employed a novel imaging protocol to obtain FDG-PET and ASL-MRI images concurrently in 17 AD patients and 19 age-matched controls. Paired FDG-PET and ASL-MRI images from 19 controls and 15 AD patients were included for qualitative analysis, while paired images 18 controls and 13 AD patients were suitable for quantitative analyses. RESULTS The combined imaging protocol was well tolerated. Both modalities revealed very similar regional abnormalities in AD, as well as comparable sensitivity and specificity for the detection of AD following visual review by two expert readers. Interobserver agreement was better for FDG-PET (kappa 0.75, SE 0.12) than ASL-MRI (kappa 0.51, SE 0.15), intermodality agreement was moderate to strong (kappa 0.45-0.61), and readers were more confident of FDG-PET reads. Simple quantitative analysis of global cerebral FDG uptake (FDG-PET) or whole brain cerebral blood flow (ASL-MRI) showed excellent diagnostic accuracy for both modalities, with area under ROC curves of 0.90 for FDG-PET (95% CI 0.79-0.99) and 0.91 for ASL-MRI (95% CI 0.80-1.00). CONCLUSIONS Our results demonstrate that FDG-PET and ASL-MRI identify similar regional abnormalities and have comparable diagnostic accuracy in a small population of AD patients, and support the further study of ASL-MRI in dementia diagnosis.

A high prevalence of PAD, considered as an ABI <0.9, was demonstrated in nondialyzed patients with CKD. This was related with age, male sex, and higher degree of renal insufficiency, while the presence of ABI > or =1.3 was associated with a greater degree of hyperparathyroidism. These data show the need to carry out routine ABI determinations in patients with CKD for early detection of peripheral arterial disease.

Heteroscorpionate-based [(L10O)MoO 2 Cl] and [(L3S)MoO 2 Cl] complexes containing an interchangeable third heteroatom donor have been utilized for the systematic investigation of oxygen atom transfer (OAT) reactivity. The detection of phosphoryl intermediates and products in the reaction pathway were probed by UV-Vis, mass spectrometry, and 31 P NMR spectroscopy. The OAT reactivity of the metal complexes toward PPh 3 were monitored by UV-Vis spectroscopy under pseudo-first order conditions. The sterically encumbered (L10O) ligand gives rise to isolable trans and cis isomers of [(L10O)MoO 2 Cl] allowing investigation into the role of geometry on OAT reactivity. The OAT reactivity of the cis isomer of (L10O)MoO 2 Cl demonstrated a dramatic solvent dependence, in which the reaction proceeded at a measureable rate only in pyridine. However, the trans counterpart reacted in all solvents and at much faster rates. The catalytic oxidation of PPh 3 to OPPh 3 by trans-[(L10O)MoO 2 Cl] and cis-[(L3S)MoO 2 Cl] complexes using DMSO as an oxygen donor was monitored by 31 P NMR in DMF at 30°C with rates, k cat = 4.26 x 10-5 s-1 and 5.28 x 10-5 s-1 , respectively.

Background: The efficacy of stroke units (SU) has been amply demonstrated in randomised trials. However, no long-term studies analysed their effectiveness in daily practice over several years of operation. Methods: Observational study from the stroke data bank of our neurology ward that includes consecutive stroke patients hospitalised since the SU was established in 1995 until the year 2002 (8 years). Clinical effectiveness was analysed in terms of mortality on day 7, in-hospital mortality, functional state at discharge, length of stay, in-hospital complications and long-term hospitalisation rates on a yearly basis using for comparisons χ² or Student t tests between the first and last 4 years of SU operation. Case-mix adjustments for baseline imbalances and stepwise multivariate logistic regression were also performed for comparative purposes. Results: 3,986 consecutive in-patients were included. No significant differences in the proportion of independent patients at discharge (73.9 vs. 74.5%; n.s.), length of stay (11.2 vs. 11.3 days; n.s.), in-hospital complications (25.0 vs. 25.9%; n.s.) or long-stay hospitalisation (6.3 vs. 6.4%; n.s.) were found comparing the first and last 4 years of SU operation. No significant differences in in-hospital mortality were found after adjustment by case-mix and length of stay. Conclusions: SU effectiveness, in terms of length of stay, death or dependence and long-term hospitalisation, is sustained over the period of operation.