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author:("baroon, R. J.")
1.  Phase II screening trial of lithium carbonate in amyotrophic lateral sclerosis 
Neurology  2011;77(10):973-979.
To use a historical placebo control design to determine whether lithium carbonate slows progression of amyotrophic lateral sclerosis (ALS).
A phase II trial was conducted at 10 sites in the Western ALS Study Group using similar dosages (300–450 mg/day), target blood levels (0.3–0.8 mEq/L), outcome measures, and trial duration (13 months) as the positive trial. However, taking riluzole was not a requirement for study entry. Placebo outcomes in patients matched for baseline features from a large database of recent clinical trials, showing stable rates of decline over the past 9 years, were used as historical controls.
The mean rate of decline of the ALS Functional Rating Scale–Revised was greater in 107 patients taking lithium carbonate (−1.20/month, 95% confidence interval [CI] −1.41 to −0.98) than that in 249 control patients (−1.01/month, 95% CI −1.11 to −0.92, p = 0.04). There were no differences in secondary outcome measures (forced vital capacity, time to failure, and quality of life), but there were more adverse events in the treated group.
The lack of therapeutic benefit and safety concerns, taken together with similar results from 2 other recent trials, weighs against the use of lithium carbonate in patients with ALS. The absence of drift over time and the availability of a large database of patients for selecting a matched historical control group suggest that use of historical controls may result in more efficient phase II trials for screening putative ALS therapeutic agents.
Classification of evidence:
This study provided Class IV evidence that lithium carbonate does not slow the rate of decline of function in patients with ALS over 13 months. Neurology® 2011;77:973–979
PMCID: PMC3171956  PMID: 21813790
2.  The non-dystrophic myotonias: molecular pathogenesis, diagnosis and treatment 
Brain  2009;133(1):9-22.
The non-dystrophic myotonias are an important group of skeletal muscle channelopathies electrophysiologically characterized by altered membrane excitability. Many distinct clinical phenotypes are now recognized and range in severity from severe neonatal myotonia with respiratory compromise through to milder late-onset myotonic muscle stiffness. Specific genetic mutations in the major skeletal muscle voltage gated chloride channel gene and in the voltage gated sodium channel gene are causative in most patients. Recent work has allowed more precise correlations between the genotype and the electrophysiological and clinical phenotype. The majority of patients with myotonia have either a primary or secondary loss of membrane chloride conductance predicted to result in reduction of the resting membrane potential. Causative mutations in the sodium channel gene result in an abnormal gain of sodium channel function that may show marked temperature dependence. Despite significant advances in the clinical, genetic and molecular pathophysiological understanding of these disorders, which we review here, there are important unresolved issues we address: (i) recent work suggests that specialized clinical neurophysiology can identify channel specific patterns and aid genetic diagnosis in many cases however, it is not yet clear if such techniques can be refined to predict the causative gene in all cases or even predict the precise genotype; (ii) although clinical experience indicates these patients can have significant progressive morbidity, the detailed natural history and determinants of morbidity have not been specifically studied in a prospective fashion; (iii) some patients develop myopathy, but its frequency, severity and possible response to treatment remains undetermined, furthermore, the pathophysiogical link between ion channel dysfunction and muscle degeneration is unknown; (iv) there is currently insufficient clinical trial evidence to recommend a standard treatment. Limited data suggest that sodium channel blocking agents have some efficacy. However, establishing the effectiveness of a therapy requires completion of multi-centre randomized controlled trials employing accurate outcome measures including reliable quantitation of myotonia. More specific pharmacological approaches are required and could include those which might preferentially reduce persistent muscle sodium currents or enhance the conductance of mutant chloride channels. Alternative strategies may be directed at preventing premature mutant channel degradation or correcting the mis-targeting of the mutant channels.
PMCID: PMC2801326  PMID: 19917643
ion channels; neuromuscular; genetics; EMG
3.  The myotubular myopathies: differential diagnosis of the X linked recessive, autosomal dominant, and autosomal recessive forms and present state of DNA studies. 
Journal of Medical Genetics  1995;32(9):673-679.
Clinical differences exist between the three forms of myotubular myopathy. They differ regarding age at onset, severity of the disease, and prognosis, and also regarding some of the clinical characteristics. The autosomal dominant form mostly has a later onset and milder course than the X linked form, and the autosomal recessive form is intermediate in both respects. These differences are, however, quantitative rather than qualitative. Muscle biopsy studies of family members are useful in some cases, and immunohistochemical staining of desmin and vimentin may help distinguish between the X linked and autosomal forms. Determining the mode of inheritance and prognosis in individual families, especially those with a single male patient, still poses a problem. Current molecular genetic results indicate that the gene for the X linked form is located in the proximal Xq28 region. Further molecular genetic studies are needed to examine the existence of genetic heterogeneity in myotubular myopathy and to facilitate diagnosis.
PMCID: PMC1051665  PMID: 8544184

Results 1-3 (3)