Background: Secondary degeneration of the pyramidal tract distal to the primary lesion after a stroke has been detected by some studies using diffusion tensor imaging (DTI) but its potential clinical significance and the degeneration of the fibre tract proximal to the primary lesion have received little attention. Methods: Twelve patients underwent DTI on the 1st, 4th and 12th week following a subcortical infarct involving the posterior limb of the internal capsule, and 12 age and sex matched controls underwent DTI once. The DTI parameters mean diffusivity and fractional anisotropy (FA), and the clinical scores before DTI examination, including the National Institutes of Health Stroke Scale (NIHSS), the Fugl-Meyer (FM) scale and the Barthel index (BI), were assessed. The relations between the per cent changes in DTI parameters and clinical scores were analysed. Results: From the 1st to the 12th week after stroke onset, FA values decreased (p,0.01, respectively) in the fibre tract above and below the internal capsule, and the NIHSS decreased (p,0.01) but the FM scale and BI increased (p,0.01, respectively) progressively. The per cent reductions in FA value in the fibre tract above and below the internal capsule were negatively correlated with the per cent changes in NIHSS and FM scale (p,0.05, respectively). Conclusions: Secondary degeneration of the fibre tract proximal and distal to a primary lesion can be detected by DTI clearly and quantitatively and deteriorates with time progressively, which may hamper functional recovery after a subcortical cerebral infarct.
Budesonide rectal foam was well tolerated and more efficacious than placebo in inducing remission in patients with mild to moderate ulcerative proctitis and ulcerative proctosigmoiditis. ClinicalTrials.gov ID: NCT01008410 and NCT01008423.
In previous experiments in tumors we demonstrated that metalloporphyrins are particularly avid for nonviable tumor components. This study was performed to find out whether these agents can be used as MRI contrast agents for the visualization of acute myocardial infarction (MI). A total of 44 rats, 6 normal controls and 38 with occlusive MI (2-24 h old), were used. Gadolinium mesoporphyrin (Gd-MP) or manganese tetraphenylporphyrin (Mn-TPP) was intravenously injected at doses of 0.1, 0.05, and 0.01 mmol/kg. Three to 24 h after injection, axial and coronal T1-weighted (TR/TE 300/15 ms) spin-echo MR images were obtained before and after killing the animals and correlated with triphenyl tetrazolium chloride (TTC) histochemical preparations. The Gd-MP content in infarcted and noninfarcted myocardium was measured using inductively coupled plasma atomic emission spectroscopy (ICP-AES). MRI without contrast media could not discern the MI. However, 3-24 h after injection of either Gd-MP or Mn-TPP, the infarcted area was positively stained on MR images. This area matched well with the negatively TTC-stained area on the heart slices (r = 0.97). The contrast ratios between the infarcted necrotic myocardium and the noninfarcted regions varied from 150 to 300% depending on the type of agents and doses used. Neither false-positive nor false-negative findings were encountered. The metalloporphyrin concentration was more than 10 times higher in the infarcted than in the noninfarcted heart. Metalloporphyrins appear to be promising MRI contrast agents for detection and quantification of necrosis in MI. These preclinical results may open new perspectives in cardiac imaging.
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