Changing motor synergies in chronic stroke

Synergies are thought to be the building blocks of vertebrate movements. The inability to execute synergies in properly timed and graded fashion precludes adequate functional motor performance. In humans with stroke, abnormal synergies are a sign of persistent neurological deficit and result in loss of independent joint control, which disrupts the kinematics of voluntary movements. This study aimed at characterizing training-related changes in synergies apparent from movement kinematics and, specifically, at assessing: 1) the extent to which they characterize recovery and 2) whether they follow a pattern of augmentation of existing abnormal synergies or, conversely, are characterized by a process of extinction of the abnormal synergies. We used a robotic therapy device to train and analyze paretic arm movements of 117 persons with chronic stroke. In a task for which they received no training, subjects were better able to draw circles by discharge. Comparison with performance at admission on kinematic robot-derived metrics showed that subjects were able to execute shoulder and elbow joint movements with significantly greater independence or, using the clinical description, with more isolated control. We argue that the changes we observed in the proposed metrics reflect changes in synergies. We show that they capture a significant portion of the recovery process, as measured by the clinical Fugl-Meyer scale. A process of "tuning" or augmentation of existing abnormal synergies, not extinction of the abnormal synergies, appears to underlie recovery.

Evidence-based guideline: assessment and management of psychiatric disorders in individuals with MS: report of the Guideline Development Subcommittee of the American Academy of Neurology

OBJECTIVE

To make evidence-based recommendations for screening, diagnosing, and treating psychiatric disorders in individuals with multiple sclerosis (MS).

METHODS

We reviewed the literature (1950 to August 2011) and evaluated the available evidence.

RESULTS AND RECOMMENDATIONS

Clinicians may consider using the Center for Neurologic Study Emotional Lability Scale to screen for pseudobulbar affect (Level C). Clinicians may consider the Beck Depression Inventory and a 2-question tool to screen for depressive disorders and the General Health Questionnaire to screen for broadly defined emotional disturbances (Level C). Evidence is insufficient to support/refute the use of other screening tools, the possibility that somatic/neurovegetative symptoms affect these tools' accuracy, or the use of diagnostic instruments or clinical evaluation procedures for identifying psychiatric disorders in MS (Level U). Clinicians may consider a telephone-administered cognitive behavioral therapy program for treating depressive symptoms (Level C). Although pharmacologic and nonpharmacologic therapies are widely used to treat depressive and anxiety disorders in individuals with MS, evidence is insufficient to support/refute the use of the antidepressants and individual and group therapies reviewed herein (Level U). For pseudobulbar affect, a combination of dextromethorphan and quinidine may be considered (Level C). Evidence is insufficient to determine the psychiatric effects in individuals with MS of disease-modifying and symptomatic therapies and corticosteroids; risk factors for suicide; and treatment of psychotic disorders (Level U). Research is needed on the effectiveness in individuals with MS of pharmacologic and nonpharmacologic treatments frequently used in the non-MS population.

Summary of evidence-based guideline: complementary and alternative medicine in multiple sclerosis: report of the guideline development subcommittee of the American Academy of Neurology

OBJECTIVE

To develop evidence-based recommendations for complementary and alternative medicine (CAM) in multiple sclerosis (MS).

METHODS

We searched the literature (1970-March 2011; March 2011-September 2013 MEDLINE search), classified articles, and linked recommendations to evidence.

RESULTS AND RECOMMENDATIONS

Clinicians might offer oral cannabis extract for spasticity symptoms and pain (excluding central neuropathic pain) (Level A). Clinicians might offer tetrahydrocannabinol for spasticity symptoms and pain (excluding central neuropathic pain) (Level B). Clinicians should counsel patients that these agents are probably ineffective for objective spasticity (short-term)/tremor (Level B) and possibly effective for spasticity and pain (long-term) (Level C). Clinicians might offer Sativex oromucosal cannabinoid spray (nabiximols) for spasticity symptoms, pain, and urinary frequency (Level B). Clinicians should counsel patients that these agents are probably ineffective for objective spasticity/urinary incontinence (Level B). Clinicians might choose not to offer these agents for tremor (Level C). Clinicians might counsel patients that magnetic therapy is probably effective for fatigue and probably ineffective for depression (Level B); fish oil is probably ineffective for relapses, disability, fatigue, MRI lesions, and quality of life (QOL) (Level B); ginkgo biloba is ineffective for cognition (Level A) and possibly effective for fatigue (Level C); reflexology is possibly effective for paresthesia (Level C); Cari Loder regimen is possibly ineffective for disability, symptoms, depression, and fatigue (Level C); and bee sting therapy is possibly ineffective for relapses, disability, fatigue, lesion burden/volume, and health-related QOL (Level C). Cannabinoids may cause adverse effects. Clinicians should exercise caution regarding standardized vs nonstandardized cannabis extracts and overall CAM quality control/nonregulation. Safety/efficacy of other CAM/CAM interaction with MS disease-modifying therapies is unknown.

Hereditary adult-onset leukodystrophy simulating chronic progressive multiple sclerosis

We studied a large kindred with a chronic progressive neurologic disorder affecting at least 10 men and 11 women in four generations in a pattern compatible with autosomal dominant inheritance. In 20 of the affected subjects, evaluated before the availability of computerized tomography and without regard to family history, the diagnosis was multiple sclerosis. Symptoms of the neurologic disorder begin in the fourth and fifth decades and include cerebellar, pyramidal, and autonomic abnormalities. The autonomic symptoms, which involve bowel and bladder regulation and orthostatic hypotension, may be the earliest changes but are frequently disregarded. Survival for 20 years after onset is common. The CT scan is striking and shows a symmetrical decrease in white-matter density, beginning in the frontal lobes but extending to all of the centrum ovale and the cerebellar white matter. Limited pathological observation reveals gross white-matter degeneration with microscopic vacuolation, preservation of U fibers and cortical structures, and no inflammatory changes or reactive gliosis. Because of its hereditary basis, the disorder should be susceptible to genetic definition and ultimately to treatment or prevention.

Learning, not adaptation, characterizes stroke motor recovery: evidence from kinematic changes induced by robot-assisted therapy in trained and untrained task in the same workspace

Both the American Heart Association and the VA/DoD endorse upper-extremity robot-mediated rehabilitation therapy for stroke care. However, we do not know yet how to optimize therapy for a particular patient's needs. Here, we explore whether we must train patients for each functional task that they must perform during their activities of daily living or alternatively capacitate patients to perform a class of tasks and have therapists assist them later in translating the observed gains into activities of daily living. The former implies that motor adaptation is a better model for motor recovery. The latter implies that motor learning (which allows for generalization) is a better model for motor recovery. We quantified trained and untrained movements performed by 158 recovering stroke patients via 13 metrics, including movement smoothness and submovements. Improvements were observed both in trained and untrained movements suggesting that generalization occurred. Our findings suggest that, as motor recovery progresses, an internal representation of the task is rebuilt by the brain in a process that better resembles motor learning than motor adaptation. Our findings highlight possible improvements for therapeutic algorithms design, suggesting sparse-activity-set training should suffice over exhaustive sets of task specific training.

Language functions in patients with multiple sclerosis

Few studies have demonstrated language impairment in patients with multiple sclerosis (MS) compared to healthy controls. The purpose of this investigation was to examine language functions, specifically naming, comprehension, and verbal fluency, in patients with MS and healthy controls to (1) determine if patients with MS demonstrate language impairment, and (2) provide clarification of MS-related language disturbance, particularly in patients with MS of differing courses. Results showed that both chronic-progressive and relapsing-remitting patients with MS performed significantly more poorly than controls on naming, aural comprehension, letter fluency, and category fluency, as well as other language-based cognitive measures. Chronic-progressive patients obtained significantly lower scores than relapsing-remitting patients on the latter three tests. The language disturbance in this MS sample may be partly explained by impairment in other verbal cognitive functions. These findings highlight the importance of assessing language abilities in patients with MS.

Performance of the dynamic single photon emission computed tomography (dSPECT) method for decreasing or increasing activity changes

Radionuclide imaging is now widely used whenever functional information is required. We present a new approach to dynamic SPECT imaging (dSPECT method) that uses a single slow rotation of a conventional camera and allows us to reconstruct a series of 3D images corresponding to the radiotracer distribution in the body at various times. Using simulations of various camera configurations and acquisition protocols, we have shown that this method is able to reconstruct washout half-lives with an accuracy greater than 90% when used with triple-head SPECT cameras. Accuracy decreases when using fewer camera heads, but dual-head geometries still give an accuracy greater than 80% for short and 90% for long half-lives and about 50-75% for single-head systems. Dynamic phantom experiments have yielded similar results. Presence of attenuation and background activity does not affect the accuracy of the dSPECT reconstructions. In all situations investigated satisfactory dynamic images were produced. A preliminary normal volunteer study measuring renal function was performed. The reconstructed dynamic images may be presented as a three-dimensional movie showing movement of the tracer through the kidneys and the measurement of the regional renal function can be performed. The time-activity curves determined from this dSPECT data are very similar to those obtained from dynamic planar scans.

The Impact of Social Media on Dissemination and Implementation of Clinical Practice Guidelines: A Longitudinal Observational Study

Background

Evidence-based clinical practice guidelines (CPGs) are statements that provide recommendations to optimize patient care for a specific clinical problem or question. Merely reading a guideline rarely leads to implementation of recommendations. The American Academy of Neurology (AAN) has a formal process of guideline development and dissemination. The last few years have seen a burgeoning of social media such as Facebook, Twitter, and LinkedIn, and newer methods of dissemination such as podcasts and webinars. The role of these media in guideline dissemination has not been studied. Systematic evaluation of dissemination methods and comparison of the effectiveness of newer methods with traditional methods is not available. It is also not known whether specific dissemination methods may be more effectively targeted to specific audiences.

Objective

Our aim was to (1) develop an innovative dissemination strategy by adding social media-based dissemination methods to traditional methods for the AAN clinical practice guidelines “Complementary and alternative medicine in multiple sclerosis” (“CAM in MS”) and (2) evaluate whether the addition of social media outreach improves awareness of the CPG and knowledge of CPG recommendations, and affects implementation of those recommendations.

Methods

Outcomes were measured by four surveys in each of the two target populations: patients and physicians/clinicians (“physicians”). The primary outcome was the difference in participants’ intent to discuss use of complementary and alternative medicine (CAM) with their physicians or patients, respectively, after novel dissemination, as compared with that after traditional dissemination. Secondary outcomes were changes in awareness of the CPG, knowledge of CPG content, and behavior regarding CAM use in multiple sclerosis (MS).

Results

Response rates were 25.08% (622/2480) for physicians and 43.5% (348/800) for patients. Awareness of the CPG increased after traditional dissemination (absolute difference, 95% confidence interval: physicians 36%, 95% CI 25-46, and patients 10%, 95% CI 1-11) but did not increase further after novel dissemination (physicians 0%, 95% CI -11 to 11, and patients -4%, 95% CI -6 to 14). Intent to discuss CAM also increased after traditional dissemination but did not change after novel dissemination (traditional: physicians 12%, 95% CI 2-22, and patients 19%, 95% CI 3-33; novel: physicians 11%, 95% CI -1 to -21, and patients -8%, 95% CI -22 to 8). Knowledge of CPG recommendations and behavior regarding CAM use in MS did not change after either traditional dissemination or novel dissemination.

Conclusions

Social media-based dissemination methods did not confer additional benefit over print-, email-, and Internet-based methods in increasing CPG awareness and changing intent in physicians or patients. Research on audience selection, message formatting, and message delivery is required to utilize Web 2.0 technologies optimally for dissemination.

Sun exposure, vitamin D and age at disease onset in relapsing multiple sclerosis

BACKGROUND

Current evidence suggests that sun exposure and vitamin D intake, during childhood and adolescence, are associated with a reduced risk of multiple sclerosis (MS). However, the role of these environmental agents in the timing of disease symptom onset remains to be investigated.

METHODS

Using a cross-sectional study design, we recruited participants from the Veterans Health Administration-Multiple Sclerosis Surveillance Registry. Self-reported histories of residential locations, sun exposure and intake of vitamin D were used to estimate vitamin-D-related exposures. Multivariable linear regression analysis was used to examine the associations between these variables and age at MS onset.

RESULTS

Among veterans with relapsing MS who resided in low-to-medium solar radiation areas (n = 540), low sun exposure in the fall/winter during the ages of 6-15 years was significantly associated with earlier symptom onset by 2.1 years (p = 0.02). Intake of cod liver oil during the same age period was associated with later onset of MS symptoms by 4 years (p = 0.02).

CONCLUSIONS

The current study provides evidence for an association between vitamin-D-related exposures during childhood and early adolescence and the timing of MS symptom onset, and supports vitamin D as a potential modulator of the clinical course of this disease.

Dual role of Response gene to complement-32 in multiple sclerosis

Response gene to complement (RGC)-32 is a novel molecule that plays an important role in cell proliferation. We investigated the expression of RGC-32 in multiple sclerosis (MS) brain and in peripheral blood mononuclear cells (PBMCs) obtained from patients with relapsing-remitting multiple sclerosis. We found that CD3(+), CD68(+), and glial fibrillar acidic protein (GFAP)(+) cells in MS plaques co-localized with RGC-32. Our results show a statistically significant decrease in RGC-32 mRNA expression in PBMCs during relapses when compared to the levels in stable MS patients. This decrease might be useful in predicting disease activity in patients with relapsing-remitting MS. RGC-32 expression was also correlated with that of FasL mRNA during relapses. FasL mRNA expression was significantly reduced after RGC-32 silencing, indicating a role for RGC-32 in the regulation of FasL expression. In addition, the expression of Akt1, cyclin D1, and IL-21 mRNA was significantly increased during MS relapses when compared to levels in healthy controls. Furthermore, we investigated the role of RGC-32 in TGF-β-induced extracellular matrix expression in astrocytes. Blockage of RGC-32 using small interfering RNA significantly inhibits TGF-β induction of procollagen I, fibronectin and of the reactive astrocyte marker α-smooth muscle actin (α-SMA). Our data suggest that RGC-32 plays a dual role in MS, both as a regulator of T-cells mediated apoptosis and as a promoter of TGF-β-mediated profibrotic effects in astrocytes.

Time of birth, residential solar radiation and age at onset of multiple sclerosis

BACKGROUNDS/AIM: Gestational and early life events have been suggested to contribute to multiple sclerosis (MS) susceptibility. We assessed the effects of time and place of birth on the age at onset of MS symptoms.

METHODS

We selected a national cohort of 967 veterans from the Multiple Sclerosis Surveillance Registry for whom month and season (time) of birth, and birthplace (city and state) were available. Multiple linear regression analyses were used to examine the association between time of birth, birthplace latitude and solar radiation, and the age at onset of MS symptoms among the study sample.

RESULTS

Patients with a relapsing form of the disease (R-MS), who were born in winter and whose birthplace was in low solar radiation areas, had disease symptom onset on average 2.8 years earlier than those born in seasons other than winter and in medium- and high-solar radiation areas (p = 0.02).

CONCLUSIONS

These results suggest that exposure early in life to geographical and seasonal factors, possibly related to the protective effect of sunlight, and thus vitamin D, is associated with a delay in MS symptom onset. Other larger studies are required to examine the period-specific (from conception to adulthood) environmental factors that are associated with MS susceptibility.

Interferon-beta-1a induces increases in vascular cell adhesion molecule: implications for its mode of action in multiple sclerosis

We investigated soluble vascular cell adhesion molecule-1 (sVCAM) levels and MRI lesions over 24 weeks in 15 Relapsing Remitting MS (RRMS) patients randomized prospectively to receive once-weekly (qw) IFN-beta-1a 30 mug intramuscularly (IM) (Group I, 8 patients) or three-times-weekly (tiw) IFN-beta-1a 44 mug subcutaneously (SC) (Group II, 7 patients). Both groups demonstrated a significant increase in sVCAM during treatment when compared to pre-treatment levels. Patients on IFN-beta-1a 44 mug SC tiw had a significant (p<0.0001) mean increase in sVCAM of 321.9 ng/ml which was significantly greater (p<0.0001) than with IFN-beta-1a 30 mug IM qw (68.6 ng/ml). There was a negative correlation between combined unique (CU) MRI lesions and sVCAM levels within the IFN-beta-1a 44 mug SC tiw group (slope=-0.00106, p=0.009). We postulate that the mode of action of IFN-beta therapy in MS may involve the induction of an increase in sVCAM. sVCAM could bind VLA-4 on T-cells and intercept their adhesion to the blood brain barrier (BBB). This mechanism is consistent with the observed clinical effect of IFN-beta in reducing MRI contrast enhancing lesions.

Comparative tolerance of IFN beta-1a regimens in patients with relapsing multiple sclerosis

The EVIDENCE study was a direct comparative study of two dose regimens of interferon (IFN) beta-1a used in the treatment of relapsing-remitting multiple sclerosis (RRMS): 30 mcg intramuscularly once weekly (qw; n=338) and 44 mcg subcutaneously three times weekly (tiw; n=339). The study continued for an average of 64 weeks. The safety population consisted of all patients receiving at least one dose of study drug. Clinical assessments occurred every 4 weeks for 24 weeks and then every 12 weeks. Blood tests for safety were taken at baseline and at weeks 4 and 12, and every 12 weeks thereafter. Overall adverse events were more common with the 44 mcg tiw regimen (p=0.007), and were due predominantly to differences in injection-site reactions. The majority of adverse events were rated mild by investigators. Hepatic and haematological adverse events and asymptomatic laboratory abnormalities were more common with 44 mcg tiw (p<0.001),with no difference seen for severe events. Flu-like symptoms were more common with 30 mcg qw (p=0.031), were more severe and persisted for longer. Serious adverse events were comparable for both groups, as were drug discontinuations. In conclusion, although adverse events were more common with high-dose, high-frequency IFN therapy, differences were primarily for mild events and did not affect treatment adherence. Based on superior clinical and magnetic resonance imaging outcomes over an average of 64 weeks, coupled with modest safety differences, the risk-benefit ratio for IFN therapy in RRMS favours the 44 mcg tiw regimen over this period of time.

Sun exposure, vitamin D intake and progression to disability among veterans with progressive multiple sclerosis

BACKGROUND

Early life events have been suggested to influence multiple sclerosis (MS) susceptibility, and to potentially modulate its clinical course. We assessed vitamin D-related exposures from childhood to disease onset and their associations with MS progression.

METHODS

Among veterans in the Multiple Sclerosis Surveillance Registry, 219 reported having the progressive form and met the inclusion criteria. Participants reported their past sun exposure, vitamin D-related intake and age at disability milestones using the Patient-Determined Disease Steps (PDDS). The Cox proportional hazards model was used to examine the association between vitamin D-related exposures and time (years) to disability.

RESULTS

Low average sun exposure in the fall/winter before disease onset was associated with an increased risk of progressing to a PDDS score of 8 (hazard ratio, HR: 2.13, 95% confidence interval, CI: 1.20-3.78), whereas use of cod liver oil during childhood and adolescence was associated with a reduced risk (HR: 0.44, 95% CI: 0.20-0.96).

CONCLUSIONS

These results suggest that exposure to vitamin D before MS onset might slow disease-related neurodegeneration and thus delay progression to disability among patients with the progressive subtype.

Psychosocial Adjustment to Multiple Sclerosis

Research has suggested that successful adaptation to multiple sclerosis (MS) and its psychological sequelae is affected by a variety of factors, but many questions remain unanswered. This study examined the extent to which certain factors contribute to successful psychosocial adjustment. Subjects were 100 MS outpatients from several MS centers and neurology clinics in the Washington, D.C. metropolitan area. Analysis showed that the following variables contributed significantly to psychosocial adjustment: disease status (i.e., remission versus exacerbation), medication, cognitive disability, and perceived uncertainty. Coping style, social support, and perceived level of physical disability did not contribute significantly to adjustment. The findings suggest that efforts should be made to reduce patients' perceptions of uncertainty regarding their MS and that cognitive functioning be assessed and appropriately accommodated in treatment.

7,8-Dihydroxyflavone improves neuropathological changes in the brain of Tg26 mice, a model for HIV-associated neurocognitive disorder

The combined antiretroviral therapy era has significantly increased the lifespan of people with HIV (PWH), turning a fatal disease to a chronic one. However, this lower but persistent level of HIV infection increases the susceptibility of HIV-associated neurocognitive disorder (HAND). Therefore, research is currently seeking improved treatment for this complication of HIV. In PWH, low levels of brain derived neurotrophic factor (BDNF) has been associated with worse neurocognitive impairment. Hence, BDNF administration has been gaining relevance as a possible adjunct therapy for HAND. However, systemic administration of BDNF is impractical because of poor pharmacological profile. Therefore, we investigated the neuroprotective effects of BDNF-mimicking 7,8 dihydroxyflavone (DHF), a bioactive high-affinity TrkB agonist, in the memory-involved hippocampus and brain cortex of Tg26 mice, a murine model for HAND. In these brain regions, we observed astrogliosis, increased expression of chemokine HIV-1 coreceptors CXCR4 and CCR5, neuroinflammation, and mitochondrial damage. Hippocampi and cortices of DHF treated mice exhibited a reversal of these pathological changes, suggesting the therapeutic potential of DHF in HAND. Moreover, our data indicates that DHF increases the phosphorylation of TrkB, providing new insights about the role of the TrkB-Akt-NFkB signaling pathway in mediating these pathological hallmarks. These findings guide future research as DHF shows promise as a TrkB agonist treatment for HAND patients in adjunction to the current antiviral therapies.