1. |
|
|
2. |
|
|
3. |
|
|
4. |
- Mattsson, B., et al.
(author)
-
Raman scattering investigations of PEO and PPO sulphonic acids
- 1997
-
In: Solid State Ionics. - : Elsevier. - 0167-2738 .- 1872-7689. ; 97:1-4, s. 309-314
-
Journal article (peer-reviewed)abstract
- Sulphonic acid derivatives of polyethers, of interest as proton conducting materials, were investigated using Raman spectroscopy, focusing on influence of hydration on ion configuration and polymer conformation. Upon increasing hydration we observe a polarised mode building up at approximately 1040 cm-1, assigned to the symmetric stretching vibration of a completely hydrated SO3- group. The data suggest that the proton-sulphonic groups do not dissociate until the materials are considerably hydrated thus explaining the low proton conductivities found for these materials below a relative humidity of 75%.
|
|
5. |
|
|
6. |
|
|
7. |
- Syvänen, Ann-Christine, et al.
(author)
-
Genetic polymorphism of catechol-O-methyltransferase (COMT) : correlation of genotype with individual variation of S-COMT activity and comparison of the allele frequencies in the normal population and parkinsonian patients in Finland
- 1997
-
In: Pharmacogenetics. - 0960-314X .- 1473-561X. ; 7:1, s. 65-71
-
Journal article (peer-reviewed)abstract
- The catechol-O-methyltransferase (COMT) gene occurs as two polymorphic alleles, which code for a high activity thermostable and low activity thermolabile form of the enzyme. We devised a fast solid-phase minisequencing assay for genotyping the COMT gene at nucleotide position 544 encoding amino acid residue 158. The method was applied to correlate the genotype of the COMT gene with the biological activity of the COMT enzyme. In red blood cells from individuals homozygous for G at nucleotide position 544 coding for Val-158, the activity of COMT ranged from 0.55-1.03 pmol min-1 mg-1 protein, and in individuals homozygous for A at position 544 coding for Met-158, the activity ranged from 0.21-0.43 pmol min-1 mg-1. Heterozygotes showed intermediate activities of 0.20-0.88 pmol min-1 mg-1. The thermostability (heated/unheated) at 48 degrees C of the high activity form was shown to be about two-fold compared to that of the low activity form of the enzyme. By analysing 76 individual samples and three pooled samples representing altogether 3140 individuals using the solid-phase minisequencing method, the two COMT alleles were shown to be equally distributed in the Finnish population. No statistically significant difference in the frequencies of the COMT alleles was found when comparing the normal population with a sample of 158 Finnish patients with Parkinson's disease.
|
|
8. |
|
|