Assessment of cerebral iron content in patients with Parkinson's disease by the susceptibility-weighted MRI.

OBJECTIVE: The overall goal of this study was to evaluate the usability of the susceptibility weighted imaging (SWI) in (1) assessment of iron deposition to enhance our ability to detect PD in the early phase and (2) in estimation of the degree of PD. PATIENTS AND METHODS: SWI scans were carried out in 54 patients with PD (18 patients with the Hoehn-Yahr scale < 1.5 and 36 patients with the Hoehn-Yahr stage > 1.5) and 40 control individuals. The phase values of the substantia nigra, red nucleus, caudate nucleus, putamen, and globus pallidus were measured on the corrected phase image. RESULTS: Compared with control individuals, patients with both the early and intermediate/ advanced stages of PD had significantly different phase values in the substantia nigra, red nucleus, caudate nucleus, putamen, and globus pallidus (all p < 0.05). The phase values of the substantia nigra and globus pallidus inversely correlated with the Hoehn-Yahr scale (respectively, r = -0.845, p < 0.05, and r = -0.868, p < 0.05). Weaker correlations were found between the phase values of red nucleus, caudate nucleus, putamen, and Hoehn-Yahr scale (red nucleus r = -0.543, caudate nucleus r = -0.620, p < 0.05, putamen r = -0.537). CONCLUSIONS: A semi-quantitative assessment of the iron content of the substantia nigra and globus pallidus with the help of SWI may be useful for early diagnosis of PD and evaluation of the degree of this disease.

Characterization of ω-secalin genes from rye, triticale, and a wheat 1BL/1RS translocation line.

Sixty-two DNA sequences for the coding regions of omega-secalin (ω-secalin) genes have been characterized from rye (Secale cereale L.), hexaploid and octoploid triticale (× Triticosecale Wittmack), and wheat (Triticum aestivum L.) 1BL/1RS translocation line. Only 19 out of the 62 ω-secalin gene sequences were full-length open reading frames (ORFs), which can be expressed into functional proteins. The other 43 DNA sequences were pseudogenes, as their ORFs were interrupted by one or a few stop codons or frameshift mutations. The 19 ω-secalin genes have a typical primary structure, which is different from wheat gliadins. There was no cysteine residue in ω-secalin proteins, and the potential celiac disease (CD) toxic epitope (PQQP) was identified to appear frequently in the repetitive domains. The ω-secalin genes from various cereal species shared high homology in their gene sequences. The ω-secalin gene family has involved fewer variations after the integration of the rye R chromosome or whole genome into the wheat or triticale genome. The higher Ka/Ks ratio (i.e. non-synonymous to synonymous substitutions per site) in ω-secalin pseudogenes than in ω-secalin ORFs indicate that the pseudogenes may be subject to a reduced selection pressure. Based on the conserved sequences of ω-secalin genes, it will be possible to manipulate the expression of this gene family in rye, triticale, or wheat 1BL/1RS translocation lines, to reduce its negative effects on grain quality.

Molecular characterization of novel low-molecular-weight glutenin genes in Aegilops longissima.

Extensive genetic variations of low-molecular-weight glutenin subunits (LMW-GS) and their coding genes were found in the wild diploid A- and D-genome donors of common wheat. In this study, we reported the isolation and characterization of 8 novel LMW-GS genes from Ae.longissima Schweinf. & Muschl., a species of the section Sitopsis of the genus Aegilops, which is closely related to the B genome of common wheat. Based on the N-terminal domain sequences, the 8 genes were divided into 3 groups. A consensus alignment of the extremely conserved domains with known gene groups and the subsequent cluster analysis showed that 2 out of the 3 groups of LMW-GS genes were closely related to those from the B genome, and the remaining was related to those from A and D genomes of wheat and Ae. tauschii. Using 3 sets of gene-group-specific primers, PCRs in diploid, tetraploid and hexaploid wheats and Ae. tauschii failed to obtain the expected products, indicating that the 3 groups of LMW-GS genes obtained in this study were new members of LMW-GS multi-gene families. These results suggested that the Sitopsis species of the genus Aegilops with novel gene variations could be used as valuable gene resources of LMW-GS. The 3 sets of group-specific primers could be utilized as molecular markers to investigate the introgression of novel alien LMW-GS genes from Ae. longissima into wheat.