The Arabidopsis glutathione transferases, AtGSTF8 and AtGSTU19 are involved in the maintenance of root redox homeostasis affecting meristem size and salt stress sensitivity

The tau (U) and phi (F) classes of glutathione transferase (GST) enzymes reduce the glutathione (GSH) pool using GSH as a co-substrate, thus influence numerous redox-dependent processes including hormonal and stress responses. We performed detailed analysis of the redox potential and reactive oxygen species levels in longitudinal zones of 7-day-old roots of Arabidopsis thaliana L. Col-0 wild type and Atsgtf8 and Atgstu19 insertional mutants. Using redox-sensitive cytosolic green fluorescent protein (roGFP2) the redox status of the meristematic, transition, and elongation zones was determined under control and salt stress (3-hour of 75 or 150 mM NaCl treatment) conditions. The Atgstu19 mutant had the most oxidized redox status in all root zones throughout the experiments. Using fluorescent dyes significantly higher superoxide radical (O₂^-) levels was detected in both Atgst mutants than in the Col-0 control. Salt treatment resulted in the highest O₂^- increase in the Atgstf8 root, while the amount of H₂O₂ elevated most in the case of Atgstu19. Moreover, vitality decreased in Atgstu19 roots more than in wild type under salt stress. Our results indicate that AtGSTF8 and especially the AtGSTU19 proteins function in the root fine-tuning the redox homeostasis both under control and salt stress conditions.

Effective cabergoline treatment in idiopathic restless legs syndrome

OBJECTIVE

To assess the efficacy and safety of the dopamine agonist cabergoline (CAB) in patients with restless legs syndrome (RLS).

METHODS

Patients with moderate to severe RLS were randomized into four groups receiving placebo, 0.5 mg, 1 mg, or 2 mg CAB once daily in a double-blind, placebo-controlled, multicenter dose-finding trial followed by an open long-term extension trial of 47 weeks. Efficacy was assessed with the RLS-6 scales and International RLS Study Group severity scale (IRLS).

RESULTS

A total of 85 patients (age 56 +/- 10 years, 71% females) were treated. Severity of RLS-6 scale symptoms during the night (the primary endpoint) was markedly improved by all CAB doses compared to placebo (placebo: -1.4 +/- 3.1, 0.5 mg CAB: -4.2 +/- 3.0 [p = 0.0082], 1.0 mg CAB: -4.0 +/- 2.9 [p = 0.0040], 2.0 mg CAB: -4.8 +/- 3.7 [p = 0.0026]). Similar results were found for the RLS severity at bedtime and during the day, IRLS, and satisfaction with sleep. A stable, clinically relevant improvement was achieved in all efficacy measures (severity during the night: change between last assessment and baseline: -5.6 +/- 2.5, rate of remission: 71.2%) throughout 1 year with a mean CAB dose of 2.2 mg per day. During long-term treatment, 6 of 66 treated patients were affected (n = 2) or possibly affected (n = 4) by mild augmentation. Under CAB therapy up to 1 year, 11 of 85 patients discontinued treatment due to a drug-related adverse event.

CONCLUSIONS

Cabergoline is an efficacious and well-tolerated option for the treatment of restless legs symptoms during the night and the day.

Transcranial magnetic stimulation as a provocation for epileptic seizures in multiple sclerosis

Epileptic seizures may be of a provoked origin in acute phases of multiple sclerosis (MS), while chronic epilepsy typically occurs in advanced stages of the disease. A case of seizure provocation during diagnostic transcranial magnetic stimulation (TMS) is described here with a corresponding central nervous system (CNS) lesion in cranial magnetic resonance imaging. A subsequent chronic epileptogenesis originating from the opposite cerebral hemisphere was observed without further TMS influence after several years. The case in its clinical rarity demonstrates that standard single pulse TMS may trigger epileptic seizures only under limited conditions. Single pulse TMS is still regarded a safe procedure in MS.

Right temporofrontal cortex as critical locus for the ecphory of old episodic memories

A 54 year old patient of average intelligence with a severe and enduring loss of old autobiographical memories after herpes simplex type 1 infection is described. She was tested with a comprehensive neuropsychological battery two years after the infection. Special emphasis was laid on examining different aspects of retrograde memory. The neurological examination involved MRI and SPECT. Brain damage was found mainly in the right temporofrontal region, but minor left sided damage to this region seems possible. The patient was in the normal or slightly subnormal range for all tested anterograde memory functions, but manifested severe retrograde memory deficits with respect to episodic old memories and more moderate deficits in tests of general knowledge (semantic old memories). It is concluded that the ecphory of old autobiographical memories relies heavily on an activation of the right lateral temporofrontal junction area, but that probably only some complementary left hemispheric damage to these regions will lead to major and persistent retrograde amnesia. Alternatively, the disconnection between major prefrontal and posterior cortical regions may provide a basis for retrograde amnesia.

[Neuropsychological aspects in idiopathic Parkinson disease]

Patients with Parkinson's disease can suffer from neuropsychological deficits which, in most cases, are already demonstrated at the very beginning (53). Primarily, they are characterized by impairments associated with frontal lobe function affecting psychomotor speed and mental flexibility. Furthermore they show circumscribed impairment of memory functions as well as deficits of visuospatial information processing. Sets of neuropsychological dysfunction of that kind are called subcortical dementia in the American literature. In addition, Parkinson's disease is quite often associated with depressive states which are independent of the neuropsychological deficits. Application of L-Dopa helps to improve the cognitive impairment.