Changes in short-term memory processes in patients with multiple sclerosis.

In this study we compared the performance of 39 multiple sclerosis (MS) patients with 28 age-, sex- and education-matched controls on both the Mini-Mental State Examination, a global cognitive assessment tool, and the Sternberg Short-Term memory scanning task, a standardized test of short-term memory (STM) processes. While the STM span of our MS patients did not differ from that of our controls, STM scanning time of the MS group was reliably slower than that of the controls and a significant correlation was observed between STM scanning time and duration but not severity of illness. Our results suggest that processing stages other than the manipulation of data within the STM buffer are also affected by MS.

Pneumococcal meningitis in the elderly.

The authors reviewed 70 cases of Streptococcus pneumoniae meningitis occurring over a 5-years period (1985-1989). Clinical features, outcome and laboratory findings in elderly patients (> 60 years of age, 21 patients) were compared with those in younger patients (< 59 years of age, 49 patients). Mortality rate was 57% in elderly group vs. 20% in younger. Admission to the hospital was delayed in the elderly. Only 67.6% of them were admitted on the first two days of the illness vs. 81.6% of younger patients. Nearly 62% of them were deeply soporous or comatose on admission (Mathew-Lawson grade 3 and 4), while in the control group only 31% of patients had such severely altered mental status. Although glucose cerebrospinal fluid (CSF)/blood ratio tended to be lower in the elderly (0.09 vs 0.17) the difference did not reach statistical significance. Thrombocytes in the peripheral blood were lower in the elderly (113 x 10(9)/L vs. 148 x 10(9)/L, p < 0.05). When we compared laboratory findings in survivors and nonsurvivors from both groups, nonsurvivors had significantly lower glucose CSF/blood ratio (0.054 vs. 0.174, p = 0.008), and higher bilirubin levels in serum (27.9 vs 14.7, p = 0.003), but differences were more obvious in younger group of patients. Our results suggest that there is increased risk of death among elderly patients. It can be at least partially attributed to their later admittance to the hospital and because of that delayed start of the appropriate therapy and more severe conscious disturbances. All these factors contribute to the greater case-fatality ratio observed in elderly patients with pneumococcal meningitis.

Vimentin and glial fibrillary acidic protein expression in relation to neoplastic cell differentiation in glial tumors.

In the present work the expression of vimentin and glial fibrillary acidic protein (GFAP) was determined in homotypic, transitional and heterotypic astroglial neoplastic areas and gemistocytes. The expression of these intermediate filament (IF) proteins within oligodendroglial neoplastic cells was determined as well. The intensity of vimentin and GFAP immunoreactivity as well as the number of immunoreactive cells within astroglial areas of different grades of differentiation were different. While there was no immunoreactivity within heterotypic areas, transitional areas and gemistocytes mainly show the same intensity of immunoreactivity and number of immunoreactive cells for both analyzed IF proteins. Within homotypic astroglial areas the number of GFAP positive cells and intensity of GFAP immunoreactivity were higher than the same vimentin parameters. It is well known that vimentin and GFAP may form heteropolymers both in vitro and in vivo. Transitions in vimentin/GFAP expression reflect not only normal development of astroglial cells but occur also with the induction of neoplastic process. Our results suggest that immunoreaction intensity and number of vimentin or GFAP immunoreactive cells correlates with the degree of differentiation of specific neoplastic cell populations. It is suggested that transitions in vimentin and GFAP expression occur in the course of neoplastic progression presumably by the modulation of their incorporation into the same IF system according to the degree of neoplastic cell differentiation.