Serum levels of alpha-tocopherol (vitamin E) in Parkinson's disease.

To elucidate the possible role of vitamin E in the pathogenesis of Parkinson's disease (PD), we compared serum levels of alpha-tocopherol (vitamin E), measured by high-performance liquid chromatography, and the vitamin E/cholesterol ratio of 42 Parkinson's disease (PD) patients using their spouses as the control group. The serum levels of vitamin E did not differ significantly between the groups (13.84 +/- 0.56 micrograms/ml for PD and 14.80 +/- 0.57 micrograms/ml for controls), nor did the vitamin E/cholesterol ratio (0.64 +/- 0.03 for both groups). There was no influence of antiparkinsonian therapy on vitamin E or the vitamin E/cholesterol ratio. Serum levels of the vitamin E and vitamin E/cholesterol ratio did not correlate with age, age at onset, scores of the Unified Parkinson's Disease Rating Scale or the Hoehn and Yahr staging in the PD group. These results suggest that serum vitamin E concentrations do not play a role in the pathogenesis of PD.     

Immunology

A selection of interesting papers that were published in the two months before our press date in major journals most likely to report significant results in immunology.     

Improved intracranial lesion characterization by tissue segmentation based on a 3D feature map

Our aim was to develop an accurate multispectral tissue segmentation method based on 3D feature maps. We utilized proton density (PD), T₂-weighted fast spin-echo (FSE), and T₁-weighted spin-echo images as inputs for segmentation. Phantom constructs, cadaver brains, an animal brain tumor model and both normal human brains and those from patients with either multiple sclerosis (MS) or primary brain tumors were analyzed with this technique. Initially, misregistration, RF inhomogeneity and image noise problems were addressed. Next, a qualified observer identified samples representing the tissues of interest. Finally, k-nearest neighbor algorithm (k-NN) was utilized to create a stack of color-coded segmented images. The inclusion of T₁ based images, as a third input, produced significant improvement in the delineation of tissues. In MS, our 3D technique was found to be far superior to that based on any combination of 2D feature maps (P < 0.001). We identified at least two distinctly different classes of lesions within the same MS plaque, representing different stages of the disease process. Further, we obtained the regional distribution of MS lesion burden and followed its changes over time. Neuropsychological aberrations were the clinical counterpart of the structural changes detected in segmentation. We could also delineate the margins of benign brain tumors. In malignant tumors, up to four abnormal tissues were identified: 1) a solid tumor core, 2) a cystic component, 3) edema in the white matter, and 4) areas of necrosis and hemorrhage. Subsequent neurosurgical exploration confirmed the distribution of tissues as predicted by this analysis.     

Solitary ileocolic arteriovenous malformation: spongostan and silk therapeutic embolisation.

A debilitated patient with liver cirrhosis and poor haemostasis had a severe lower gastrointestinal haemorrhage. A superior mesenteric arteriogram revealed an early persistent and promiment draining vein in the ileocolic artery. Two fragments of Spongostan and silk were used to embolise the bleeding artery and the haemorhage ceased immediately. No infarction of the embolised area was observed and the bleeding was controlled.     

The Organization of the Venous Spaces of the Cavernous Sinus

The study of the venous channels in the cavernous sinus in 48 sphenoid bones was performed. Thirty-eight bones were electrolyticly decalcified, subsequently embedded in gelatin, and cut in 1 mm thick slices. Microdissection of the other ten specimens complemented the analysis. Every specimen had the venous structure arranged as a plexus, however, although the channels were variable in number, form, and diameter, the two sides were quite symmetrical. Channels of smaller diameter predominated anteriorly. There was no demonstrable muscular layer in these vessels; the endothelial lining was easily visualized. Fatty tissue separated the venous channels from each other and from arteries and nerves. The distance from the carotid artery and the lateral wall increased anteriorly, but there were significant veins between these two structures in only 35% of the cases. In about one third of specimens the oculomotor nerve was placed over the carotid artery. The abducens nerve was found to be intimately related to the lateral wall without any venous channels between them in 92% of the specimens.     

Coronary permeability and left ventricular function following thrombolytic therapy

We study 40 patients, 55 +/- 7 years old with acute myocardial infarction treated early by thrombolytic therapy (20 STK and 20 rt-PA). All patients were angiographically studied in the following conditions: 1) baseline, before initiating therapy. 2) Three hours after treatment. 3) Twenty four hours later. 4) Before discharge. The infarct related artery was patent 24 hours after treatment in 31 patients (78%); five of them were patent before treatment, and we observed an early reperfusion in 20 patients (57%) and late reperfusion in 6 patients (17%). The number of patients with angiographic evidence of intraluminal thrombus decreased progressively through conditions while the grade TIMI of coronary perfusion increased in the absence of reocclusion. Final regional wall motion of infarct related myocardial zones and their degree of recovery were significantly higher in recanalized patients, as compared with non-reperfused patients. Similarly, left ventricular functional recovery was higher in patients with antegrade of collateral flow to the infarct area, as compared with totally occluded patients.