Biomedical subjects

K Linnaranta

Publications and source records attributed to K Linnaranta.

3 recordsLinked to original sources

PubMed1998

CSF tau is related to apolipoprotein E genotype in early Alzheimer's disease.

We quantified microtubule-associated protein tau in CSF (CSF tau) using ELISA assay in 168 subjects: 81 patients with clinically diagnosed early Alzheimer's disease (AD), 43 patients with other dementia, 11 Down's syndrome patients, and 33 nondemented neurologic control subjects. Multivariate ANOVA showed an effect of diagnostic group (p < 0.01) and apolipoprotein E (apoE) allele (p < 0.005) on CSF tau. Comparison between diagnostic groups showed higher CSF tau levels in AD than in the control group (p < 0.001). However, CSF tau values in the non-AD dementia group did not differ significantly from those of AD patients or neurologic control subjects. Tau levels were increased (p < 0.005) in AD patients with apolipoprotein E epsilon4 allele, a well-characterized risk factor of AD, compared with AD patients without epsilon4 allele, and the highest values were found in AD patients with two epsilon4 alleles. These increased levels of CSF tau may indicate pronounced neuronal degeneration and neurofibrillar pathology at the early stage of AD in patients carrying the epsilon4 allele. This study shows that the current ELISA test for CSF tau is not sensitive and specific enough to distinguish early AD from other dementias and indicates that in the interpretation of CSF tau analysis as a diagnostic tool, the apoE genotype should also be taken into account.

Adult↗

PubMed1996

Apolipoprotein E polymorphism in patients with different neurodegenerative disorders.

Apolipoprotein E (ApoE) is associated with Alzheimer's disease (AD) neurofibrillary tangles and beta-amyloid protein in senile plaques. There are three common alleles of ApoE, designated epsilon 2, epsilon 3 and epsilon 4. We studied Finnish patients with neurodegenerative disorders: AD, vascular dementia (VAD), Parkinson's disease (PD), PD+dementia (PDD), Lewy body variant of AD (LB), frontal dementia (FD), and Down's syndrome (DS), as well as control individuals (C). The ApoE genotypes and corresponding allele frequencies of 188 patients and 60 controls were determined by digestion of ApoE polymerase chain reaction products with the restriction enzyme Hha I. The ApoE epsilon 4 allele frequency was 0.17 for C, 0.44 for AD, 0.35 for VAD, 0.10 for PD, 0.38 for PDD, 0.28 for LB, 0.39 for FD, and 0.17 for DS. We found significant differences in genotype frequency between AD/C, AD/PD and AD/DS. Our results suggest that, beside AD, an increased frequency of epsilon 4 may also be involved in other dementing neurological disorders.

Adult↗

PubMed1995

Increased acetylcholinesterase activity in the CSF of Alzheimer patients carrying apolipoprotein epsilon4 allele.

We measured CSF acetylcholinesterase (AChE) activity in 57 Alzheimer's disease (AD) patients with different apolipoprotein E (apoE) genotypes at the early stage of the disease, and in 11 non-demented controls. The AChE activities of the whole AD group did not differ from those of controls. However, analysis of variance over the AD subgroups with two, one or no epsilon4 alleles and controls showed significant differences (p < 0.0001); the AD patients with two epsilon4 alleles had higher AChE activities than controls and AD patients with one or no epsilon4 and also the AD patients carrying one epsilon4 allele had higher AChE activities than the AD patients without the epsilon4 allele. The study suggests that cholinergic metabolism is altered in proportion to the number of apoE epsilon4 alleles. The different degree of AChE activity in relation to the number of epsilon4 alleles might have an impact on AD patients' responses to cholinesterase inhibitors.

Acetylcholinesterase↗