ABSTRACT
Since the spring of 1997, when the Neurology Department of the University Hospital of Crete admitted its first patient, nine cases (eight neuropathologically confirmed and one probable) of sporadic Creutzfeldt-Jakob disease (sCJD) have been recorded. This represents an annual incidence five-fold higher than expected based on the island's population (0.54 million). Molecular analysis of the prion-protein gene (PRNP) showed no mutations in any of the seven CJD cases studied. Five patients (ages 64-88 years) were homozygous for methionine-129 of PRNP and showed the classic sCJD triad (subacute dementia, myoclonus, periodic electroencephalogram). Brains contained type 1 (unglycosylated 21.5 kDa band) protease-resistant prion protein (PrPres). Two patients (ages 56 and 57 years), both homozygous for valine-129, showed cerebellar ataxia and later dementia not associated with periodic electroencephalogram; brain PrPres was type 2. Genotyping of 205 Cretan controls showed that methionine-129 homozygosity, a susceptibility factor for sCJD, was significantly higher in this population than in other Caucasian populations (57.0% n = 205 vs. 41.5% n = 859, p < 0.0001). These data are the first to relate a high regional incidence rate for sCJD to the distribution of PRNP 129 genotypes in the local population; however, additional factors may be operational.
Subject(s)
Amyloid/genetics , Creutzfeldt-Jakob Syndrome/pathology , Protein Precursors/genetics , Age Factors , Aged , Aged, 80 and over , Blotting, Western , Cerebral Cortex/pathology , Creutzfeldt-Jakob Syndrome/epidemiology , Creutzfeldt-Jakob Syndrome/genetics , Female , Genotype , Greece/epidemiology , Humans , Immunohistochemistry , Incidence , Male , Middle Aged , Prion Proteins , PrionsABSTRACT
The MIB1 monoclonal antibody which is used as a marker of cell proliferation was studied by immunohistochemistry on formalin-fixed and paraffin embedded biopsy specimens of lymph nodes in 40 high- and 46 lowgrade cases of non-Hodgkin's lymphomas (NHL) classified according to the Kiel classification. All cases were found to display nuclear MIB1 staining. A statistically significant difference (P < 0.005) was found between high- and low grade NHLs and this indicates that the high- grade NHL display a higher proliferation rate than low grade. In addition, remarkable variations in MIB1 expression were found among individual cases of the same histological group. These data may suggest that MIB1 index can help in the individual approach of the proliferation rate of each tumour and this may be an important parameter in association with clinical and other laboratory parameters for predicting the biological behaviour of non-Hodgkin's lymphomas.
