Meningiomas are one of the most common CNS tumors whose appearance is closely linked to NF2 gene product merlin. Tumor markers Ki-67 and p53 play established role in tumor progression which should be analyzed in close association with merlin expression. The aim of this study was to investigate the immunohistochemical expression of merlin in meningiomas, correlation with Ki-67 and p53, and to determine the association of these results with histologic grade and subtype. The histologic sections of 170 patients with totally resected meningiomas, between January 2000 and December 2010, were classified according to WHO, immunohistochemically stained for Ki-67, p53, and merlin, and analyzed using light microscope. Ki-67 median was 5.6 times higher in group of patients with negative merlin than in those with positive merlin (P=0.05). Statistically significant correlation of merlin with p53 was found (P<0.001). Merlin expression between 2 combined groups (meningothelial/secretory and fibroblastic/transitional) was statistically significant (P=0.002). By comparing merlin expression and p53 levels, statistically significant difference was found (P=0.017). In the group with positive merlin and negative p53 as well as positive merlin and low p53, meningothelial/secretory subtypes of meningiomas were more common. In combination of negative merlin and negative p53 as well as negative merlin and high p53, there were more meningiomas of fibroblastic/transitional subtype. There was no statistically significant correlation between merlin and tumor grade (P=0.420). There is undeniable influence of merlin on the development and the proliferative ability of meningioma subtypes. Significant role of p53 pathway was confirmed.
SummaryBackgroundThe aim of this study was to examine the impact of intravenous methylprednisolone therapy (IVMP) on the recovery of walking ability in patients experiencing multiple sclerosis (MS) relapses, to compare the responsiveness of walking-based measures, and to estimate the impact of different walking-based measures responsiveness on clinical trials.Material/MethodsThe study included 49 consecutive patients with relapsing-remitting MS who received Solu-Medrol 1000 mg/day over 3 days for relapse with difficulties in walking. The following walking-based measures were administered before and a month after IVMP: the Multiple Sclerosis Walking Scale-12 (MSWS-12), the Expanded Disability Status Scale (EDSS), the 2-minute timed walk (2-minTW), the 25-foot walk test (25FWT), the Six Spot Step Test (SSST). All patients had worn the step activity monitor accelerometer (SAM) 1 week prior to IVMP was applied and wore it again the fourth week upon the corticosteroid therapy was completed. The SAM analysis utilized the average daily step count and data regarding frequency and intensity of walking over a continuous time interval. We examined: (1) the impact of IVMP on the recovery of walking ability; (2) the responsiveness of each walking-based measure; (3) the relative responsiveness of competing walking-based measures; and (4) the impact of different walking-based measures responsiveness on clinical trials.ResultsAll walking-based measures showed significant improvement of walking ability 1 month after the IVMP. The most responsive were MSWS-12 and EDSS. Different responsiveness implied a greater than 6-fold impact on sample size estimates.ConclusionsAll applied walking-based measures showed significant improvement of walking ability 1 month after the IVMP. Responsiveness of various walking-based measures notably differ, thus affecting sample size calculations.
Various malignant tumors of the liver, especially liver angiosarcoma, have been described after occupational exposure to vinyl chloride monomer. We present the case records and pathologic findings of two plastic industry workers who had been exposed to high concentrations of vinyl chloride. These workers developed hepatic neoplasms, angiosarcoma, or hemangiopericytoma. We discuss the histogenesis of these tumors; the common vascular origin and the mutual transformation of these two tumors suggest that the hemangiopericytoma may also have developed during occupational exposure to high concentrations of vinyl chloride monomer.ImagesFigure 1Figure 2
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