Phonoarticulation in spinocerebellar ataxia type 3.

Phonoarticulation is characterized by changes in resonance, diadochokinesis, prosody, sound frequency, vocal quality, and intraoral pressure. The main aim of this study was to characterize the phonoarticulation in spinocerebellar ataxia type 3 (SCA3) and correlate it with clinical and genetic factors. Thirty-one patients with SCA3 who were subjected to spontaneous speech recordings and phonoarticulatory diadochokinesis (DDK) participated in the study. Speech analyses were performed starting after 10 s of spontaneous speech, by three experienced speech therapists, using a protocol for dysarthria adapted from the Mayo Clinic. The intra-evaluator reliability was analyzed. The lower the patient's age at disease onset was, the more frequent the occurrences of monofrequency and altered speech rhythm were. Articulation, DDK, resonance, and prosody showed a moderate correlation with the number of "CAG" triplet repeats. We conclude that the phonoarticulation of patients with Machado-Joseph disease (MJD) is characterized by mixed dysarthrophonia with cerebellar and hypokinetic components, and that there is a tendency toward higher frequency of dysarthrophonia symptoms with lower age of disease onset, longer time since onset and higher number of "CAG" triplet repeats.

Characterization of glutathione S-transferases in needles of Norway spruce trees from a forest decline stand.

Glutathione S-transferases (GST) detoxify many electrophilic xenobiotics, including several volatile organic compounds and pesticides. The GST activity for the conjugation of several xenobiotic substances was isolated from needles of Norway spruce (Picea abies L. Karst.) trees from a forest decline stand in the northern alps. Trees that exhibited different degrees of damage were selected from several stands in an altitude profile. The GST activity toward 1-chloro-2,4-dinitrobenzene (CDNB) in crude protein extracts of needles showed a seasonal pattern with highest activity during summer. The GST activity exhibited a strong dependence on the altitude of the stand showing highest activities in trees growing in the valley and lowest activities in trees growing in the summit regions of the mountain. When cytosolic GST from needles of healthy and damaged trees was purified, trees of healthy appearance exhibited three distinct GST isozymes with activities for the conjugation of CDNB and 1,2-dichloro-4-nitrobenzene (DCNB), whereas severely defoliated trees exhibited four GSTs with additional activity for the conjugation of ethacrynic acid. The main GST isozymes catalyzing the conjugation of CDNB differed in molecular weight, isoelectric point and catalytic properties between damaged and healthy trees.

Degradation of glutathione S-conjugates by a carboxypeptidase in the plant vacuole.

For plants, glutathione conjugation is a major pathway to detoxify organic xenobiotic. Glutathione S-conjugates (SG-conjugates) are formed in the cytosol, the in vitro transport over the tonoplast has been described and a final storage in the vacuole has been postulated. We show here that alachlor rapidly accumulates as GS-conjugates in the plant vacuole and that the first step of its degradation, the formation of the respective gamma-glutamylcysteinyl-S-conjugate, is catalyzed by a vacuolar carboxypeptidase. These results suggest the glutathione conjugate as a transport form but not a storage form of xenobiotic molecules.