Automated Assessment of Oral Diadochokinesis in Multiple Sclerosis Using a Neural Network Approach: Effect of Different Syllable Repetition Paradigms.

Slow and irregular oral diadochokinesis represents an important manifestation of spastic and ataxic dysarthria in multiple sclerosis (MS). We aimed to develop a robust algorithm based on convolutional neural networks for the accurate detection of syllables from different types of alternating motion rate (AMR) and sequential motion rate (SMR) paradigms. Subsequently, we explored the sensitivity of AMR and SMR paradigms based on voiceless and voiced consonants in the detection of speech impairment. The four types of syllable repetition paradigms including /ta/, /da/, /pa/-/ta/-/ka/, and /ba/-/da/-/ga/ were collected from 120 MS patients and 60 matched healthy control speakers. Our neural network algorithm was able to correctly identify the position of individual syllables with a very high average accuracy of 97.8%, with the correct temporal detection of syllable position of 87.8% for 10 ms and 95.5% for 20 ms tolerance value. We found significantly altered diadochokinetic rate and regularity in MS compared to controls across all types of investigated tasks ( ). MS patients showed slower speech for SMR compared to AMR tasks, whereas voiced paradigms were more irregular. Objective evaluation of oral diadochokinesis using different AMR and SMR paradigms may provide important information regarding speech severity and pathophysiology of the underlying disease.

Pathological cut-offs of global and regional brain volume loss in multiple sclerosis.

BACKGROUND: Volumetric MRI surrogate markers of disease progression are lacking. OBJECTIVE: To establish cut-off values of brain volume loss able to discriminate between healthy controls and MS patients. METHODS: In total, 386 patients after first demyelinating event suggestive of MS (CIS), 964 relapsing-remitting MS (RRMS) patients, 63 secondary-progressive MS (SPMS) patients and 58 healthy controls were included in this longitudinal study. A total of 11,438 MRI scans performed on the same MRI scanner with the same protocol were analysed. Annualised percentage changes of whole brain, grey matter, thalamus and corpus callosum volumes were estimated. We investigated cut-offs able to discriminate between healthy controls and MS patients. RESULTS: At a predefined specificity of 90%, the annualised percentage change cut-off of corpus callosum volume (-0.57%) was able to distinguish between healthy controls and patients with the highest sensitivity (51% in CIS, 48% in RRMS and 42% in SPMS patients). Lower sensitivities (22%-49%) were found for cut-offs of whole brain, grey matter and thalamic volume loss. Among CIS and RRMS patients, cut-offs were associated with greater accumulation of disability. CONCLUSION: We identified cut-offs of annualised global and regional brain volume loss rates able to discriminate between healthy controls and MS patients.

Humoral responses to herpesviruses are associated with neurodegeneration after a demyelinating event: results from the multi-center set study.

OBJECTIVES: To investigate the associations between antibody responses to herpesviruses and the development of thalamic, total deep gray matter, cortical and central atrophy in high-risk clinically isolated syndromes (CIS) after the first demyelinating event. METHODS: We analyzed volumetric brain outcomes in 193 CIS patients enrolled in a multi-center study of high-risk CIS. All patients had 2 or more MRI brain lesions and two or more oligoclonal bands in cerebrospinal fluid. Serum samples obtained at the screening visit prior to any treatment were analyzed for IgG antibodies against cytomegalovirus (anti-CMV) and Epstein-Barr virus (EBV) viral capsid antigen (VCA). All patients were treated with interferon-beta. Clinical and MRI assessments were obtained at baseline, 6, 12, and 24 months. RESULTS: Anti-EBV VCA highest quartile status was associated with regional atrophy measures for percent decrease in thalamus. Anti-CMV positivity was associated with greater total deep gray matter atrophy and whole brain atrophy. Anti-EBV VCA highest quartile status was associated as trends with greater whole brain, gray matter atrophy and central atrophy. The associations of anti-EBV VCA antibodies with thalamic atrophy were mediated by its associations with T2 lesions whereas the associations of anti-CMV positivity with deep gray matter atrophy were relatively independent of T2 lesions. CONCLUSIONS: Antibody responses to EBV and CMV are associated with global and regional brain atrophy in CIS patients treated with interferon-beta.

Lipid profiles are associated with lesion formation over 24 months in interferon-ß treated patients following the first demyelinating event.

OBJECTIVES: To investigate the associations of serum lipid profile with disease progression in high-risk clinically isolated syndromes (CIS) after the first demyelinating event. METHODS: High density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) were obtained in pretreatment serum from 135 high risk patients with CIS (≥ 2 brain MRI lesions and ≥ 2 oligoclonal bands) enrolled in the Observational Study of Early Interferon ß-1a Treatment in High Risk Subjects after CIS study (SET study), which prospectively evaluated the effect of intramuscular interferon ß-1a treatment following the first demyelinating event. Thyroid stimulating hormone, free thyroxine, 25-hydroxy vitamin D3, active smoking status and body mass index were also obtained. Clinical and MRI assessments were obtained within 4 months of the initial demyelinating event and at 6, 12 and 24 months. RESULTS: The time to first relapse and number of relapses were not associated with any of the lipid profile variables. Higher LDL-C (p=0.006) and TC (p=0.001) levels were associated with increased cumulative number of new T2 lesions over 2 years. Higher free thyroxine levels were associated with lower cumulative number of contrast-enhancing lesions (p=0.008). Higher TC was associated as a trend with lower baseline whole brain volume (p=0.020). Higher high density lipoprotein was associated with higher deseasonalised 1,25-dihydroxy vitamin D3 (p=0.003) levels and a trend was found for deseasonalised 25-hydroxy vitamin D3 (p=0.014). CONCLUSIONS: In early multiple sclerosis, lipid profile variables particularly LDL-C and TC levels are associated with inflammatory MRI activity measures.

Thalamic atrophy is associated with development of clinically definite multiple sclerosis.

PURPOSE: To investigate the association between the development of thalamic and cortical atrophy and the conversion to clinically definite multiple sclerosis (CDMS) in patients with clinically isolated syndrome (CIS). MATERIALS AND METHODS: This prospective study was approved by the institutional review board. Informed consent was given by 216 CIS patients, and patients were treated with 30 µg of intramuscular interferon ß1a once a week. They were assessed with a magnetic resonance (MR) imaging examination at baseline, 6 months, 1 year, and 2 years. Patients were evaluated within 4 months of an initial demyelinating event, had two or more brain lesions on MR images, and had two or more oligoclonal bands in cerebrospinal fluid. MR imaging measures of progression included cumulative number and volume of contrast agent-enhanced (CE) new and enlarged T2 lesions, and changes in whole-brain, tissue-specific global, and regional gray matter volumes. Regression and mixed-effect model analyses were used. RESULTS: Over 2 years, 92 of 216 patients (42.6%) converted to CDMS; 122 (56.5%) CIS patients fulfilled McDonald 2005 criteria and 153 (70.8%) fulfilled McDonald 2010 criteria for MR imaging dissemination in time and space. The mean time to first relapse was 3.1 months, and mean annual relapse rate was 0.46. In mixed-effect model analysis, the lateral ventricle volume (P = .005), accumulation of CE (P = .007), new total T2 (P = .009) and new enlarging T2 lesions (P = .01) increase, and thalamic (P = .009) and whole-brain (P = .019) volume decrease were associated with development of CDMS. In multivariate regression analysis, decrease in thalamic volumes and increase in lateral ventricle volumes (P = .009) were MR imaging variables associated with the development of CDMS. CONCLUSION: Measurement of thalamic atrophy and increase in ventricular size in CIS is associated with CDMS development and should be used in addition to the assessment of new T2 and CE lesions.

Luminometric method for screening retroviral protease inhibitors.

We have developed a sensitive luminometric assay for determining the activity of retroviral proteases that uses proteolytic cleavage of polypeptide substrate immobilized on Ni-NTA HisSorb Strips microplates. The protease substrate derived from the Gag precursor protein of Mason-Pfizer monkey virus (M-PMV) was conjugated with horseradish peroxidase (HRP), which catalyzes oxidation of luminol in the assay. The cleavage of the substrate was monitored as a decrease in luminescent signal caused by the release of the cleavage product conjugated to HRP. Testing of a set of M-PMV protease inhibitors confirmed that this method is sufficiently sensitive and specific for high-throughput screening of retroviral protease inhibitors.