Prorating WAIS – IV summary scores for patients with relapsing-remitting multiple sclerosis

We evaluated the utility of prorating appropriate combinations of two, six and eight Wechsler Adult Intelligence Scale – Fourth Edition (WAIS – IV) subtests for estimating the Verbal Comprehension Index (VCI), Perceptual Reasoning Index (PRI), Full Scale IQ (FSIQ) and General Ability Index (GAI) in a sample of individuals diagnosed with multiple sclerosis (MS). Forty-eight outpatients completed the WAIS – IV and Wechsler Memory Scale – Fourth Edition (WMS – IV) as part of a comprehensive neuropsychological battery. Means for age, education and duration of diagnosis were 42.35, 14.21 and 8.30 years, respectively. Paired t-tests showed no significant differences between prorated and standard means for VCI (93.46 vs. 93.73), PRI (90.19 vs. 89.44), FSIQ (88.53 vs. 88.47) or GAI (90.56 vs. 90.65). Correlations between prorated and standard composites were ≥0.89 in every instance. Correlations between the standard and prorated composites and education, disability status and WMS – IV indexes did not reveal a single contrast, where the correlations were significantly different. The present findings support the use of the two-subtest VCI and PRI composites and the eight-subtest FSIQ and four-subtest GAI in the assessment of patients with MS.     

Assessing patterns of participation and enjoyment in children with spinal cord injury

Aim To determine patterns of participation and levels of enjoyment in young people with spinal cord injuries (SCI) and to assess how informal and formal participation varies across child, injury‐related, household, and community variables. Method One hundred and ninety‐four participants (106 males, 88 females; mean age 13y 2mo, SD 3y 8mo, range 6–18y) with SCI and their primary caregivers completed a demographics questionnaire and a standardized measure of participation (the Children’s Assessment of Participation and Enjoyment, [CAPE]) at three pediatric SCI centers in a single hospital system in the United States. Their mean age at injury was 7 years 2 months (SD 5y 8mo, range 0–17y); 71% had paraplegia, and 58% had complete injuries. Results Young people participated more often in informal activities (t₍₁₇₄₎=29.84, p<0.001) and reported higher enjoyment with these (t₍₁₇₄₎=2.01, p=0.046). However, when engaging in formal activities, they participated with a more diverse group (t₍₁₇₄₎=−16.26, p<0.001) and further from home (t₍₁₇₄₎=−16.08, p<0.001). Aspects of informal participation were related to the child’s age, sex, and injury level, and formal participation to the child’s age and caregiver education. Caregiver education was more critical to formal participation among young people with tetraplegia than among those with paraplegia (F_(4,151)=2.67, p=0.034). Interpretation Points of intervention include providing more participation opportunities for young people with tetraplegia and giving caregivers the resources necessary to enhance their children’s formal participation.     

Psychometric properties of the Parkinson's Disease Sleep Scale – Brazilian version

Parkinson's Disease Sleep Scale (PDSS) is a specific scale for the assessment of sleep disturbances in subjects with Parkinson's Disease (PD). This cross-sectional study set out to validate the PDSS in a Brazilian Portuguese Version (PDSS-BR). Ninety-five patients with PD participated in the study; their PD symptoms were evaluated by Unified Parkinson's Disease Rating Scale (UPDRS sections I–IV) and Hoehn and Yahr scale. Patients completed Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Beck Depression Inventory (BDI) and PDSS-BR. PDSS-BR internal consistency was satisfactory (Cronbach's α: 0.82; all PDSS-BR items were significantly and positively associated with total score). Test–retest reliability for total PDSS-BR score was 0.94. PDSS-BR score was highly correlated with sleep PSQI scale (r_s = ?0.63; p < 0.0001) and moderately with ESS (r_s = ?0.32; p < 0.001) and UPDRS sections I (r_s = ?0.38; p < 0.0001) and II (r_s = ?0.36; p < 0.0001) and BDI (r_s = ?0.55; p < 0.0001). Depressive symptoms, as determined by the BDI, were associated with significantly worse quality of nocturnal sleep, as measured by the PDSS-BR.The psychometric attributes of the PDSS-BR were satisfactory and consistent with those of previous studies. In summary, PDSS-BR can be useful for clinical and research purposes in Brazil.     

Stress and coping mechanisms among adolescents living in orphanages: An experience from Klang Valley,Malaysia

Introduction

Health issues often differ from one population to another. Assessing different aspects of the health condition is a vital step toward developing and designing appropriate prevention and treatment programs to reduce health problems in any group or population. This study aimed to assess both the prevalence of stress and the coping mechanisms as well as identify the predictors of stress levels among adolescents in Malaysian orphanages.

Methods

Overall, 307 male and female adolescents (aged 13‐18 y old) living in 9 private orphanages located in Klang Valley, Malaysia, participated in this cross‐sectional study. Brief COPE scale and Depression, Anxiety and Stress Scale‐21 were used as the main instruments in the current study.

Results

The results of the current study showed female adolescents and participants with a higher level of education were more likely to experience stress. The results also showed significant differences between boys and girls in using of coping mechanisms in self‐distraction (t = ?2.39, P = .01), substance use (t = 2.12, P = .03), use of emotional support (t = ?2.70, P = .001), humor (t = 2.28, P = .02), and religion (t = ?2.19, P = .02). Denial, venting, religion, humor, planning, and active coping were identified as predictors of stress among participants.

Discussion

The results showed a high prevalence of stress and a negative coping pattern among participants. The finding of the current study also showed the urgency of taking immediate action to reduce stress and improve coping methods among Malaysian institutional adolescents.     

Occipital blood‐brain barrier permeability is an independent predictor of visual outcome in type 2 diabetes,irrespective of the retinal barrier: A longitudinal study

Blood‐brain barrier (BBB) permeability in type 2 diabetic patients has been previously shown to be altered in certain brain regions such as the basal ganglia and the hippocampus. Because of the histological and functional similarities between the BBB) and the blood‐retinal barrier (BRB), we aimed to investigate how the permeability of both barriers predicts visual outcome. We included 2 control groups (acute unilateral stroke patients, n = 9; type 2 diabetics without BRB leakage n = 10) and a case study group of type 2 diabetics with established BRB leakage (n = 17). We evaluated sex, age, disease duration, metabolic impairment, retinopathy grade and BBB permeability as predictors of visual acuity at baseline, 12  and 24 months in the type 2 diabetics without BRB leakage group and the case study group. We have also explored differences in BBB permeability in the occipital lobe and frontal lobe in the 3 different groups. K^trans (volume transfer coefficient) and V_p (fractional plasma volume) were estimated. The BBB permeability parameter V_p was higher in the case study group compared to the unaffected hemisphere of the stroke patient control group, suggesting vascular dynamics were changed in the occipital lobe of type 2 diabetics with established BRB leakage. These patients showed a significant correlation between glycated hemoglobin (HbA1C) levels and occipital and frontal K^trans. We report for the first time that occipital BBB permeability is an independent predictor of visual acuity at baseline, as well as at 12 and 24 months, in type 2 diabetics with established BRB leakage. Our results suggest that occipital BBB permeability might be an independent biomarker for visual impairment in patients with established BRB leakage.     

High disease impact of myotonic dystrophy type 2 on physical and mental functioning

The aim of the study was to investigate health status in patients with myotonic dystrophy type 2 (DM2) and determine its relationship to pain and fatigue. Data on health status (SF-36), pain (MPQ) and fatigue (CIS-fatigue) were collected for the Dutch DM2 population (n = 32). Results were compared with those of sex- and age-matched adult-onset myotonic dystrophy type 1 (DM1) patients. In addition, we compared the obtained scores on health status of the DM2 group with normative data of the Dutch general population (n = 1742). Compared to DM1, the SF-36 score for bodily pain was significantly (p = 0.04) lower in DM2, indicating more body pain in DM2. DM2 did not differ from DM1 on any other SF-36 scales. In comparison to the Dutch population, DM2 patients reported lower scores (indicating worse clinical condition) on the physical functioning, role functioning-physical, bodily pain, general health, vitality, social functioning, and role functioning-emotional scales (p < 0.01 on all scales). The difference was most profound for the physical functioning scale. In the DM2 group the severity of pain was significantly correlated with SF-36 scores for bodily pain (p = 0.003). Fatigue was significantly correlated with the SF-36 scores for role functioning-physical (p = 0.001), general health (p = 0.02), and vitality (p = 0.02). The impact of DM2 on a patients’ physical, psychological and social functioning is significant and as high as in adult-onset DM1 patients. From the perspective of health-related quality of life, DM2 should not be considered a benign disease. Management of DM2 patients should include screening for pain and fatigue. Symptomatic treatment of pain and fatigue may decrease disease impact and help improve health status in DM2, even if the disease itself cannot be treated.     

Chronic depressive symptomatology and CSF amyloid beta and tau levels in mild cognitive impairment

Objectives

To investigate the association between chronic subsyndromal symptoms of depression (SSD), cerebrospinal fluid (CSF) biomarkers, and neuropsychological performance in individuals with mild cognitive impairment (MCI).

Methods

Participants included 238 older adults diagnosed with MCI from the Alzheimer's Disease Neuroimaging Initiative repository with cognitive and CSF amyloid beta (Aβ_1–42), total tau (t‐tau), and phosphorylated tau (p‐tau) data. The Neuropsychiatric Inventory identified individuals with chronic endorsement (SSD group N = 80) or no endorsement (non‐SSD group N = 158) of depressive symptoms across timepoints. CSF biomarker and cognitive performance were evaluated with linear regression models adjusting for age, education, gender, APOE genotype, global cognitive status, and SSD group.

Results

As compared to the non‐SSD group, the SSD group displayed lower CSF Aβ_1–42 levels (β = ?24.293, S.E. = 6.345, P < 0.001). No group differences were observed for CSF t‐tau (P = 0.497) or p‐tau levels (P = 0.392). Lower CSF Aβ_1–42 levels were associated with poorer performance on learning (β = 0.041, S.E. = 0.018, P = 0.021) and memory (β = ?0.012, S.E. = 0.005, P = 0.031) measures, whereas higher CSF t‐tau levels were associated with poorer performance on measures of global cognition (β = 0.022, S.E = 0.008, P = 0.007) and language (β = ?0.010, S.E = 0.004, P = 0.019). SSD was independently associated with diminished global cognition, learning and memory, language, and executive function performance over and above the effects of CSF biomarkers (all P < 0.05).

Conclusions

MCI participants with SSD displayed diminished CSF Aβ_1–42 levels but did not differ from non‐SSD controls in CSF tau levels. Additionally, CSF biomarkers and SSD independently accounted for variance in cognitive performance, suggesting that these factors may uniquely confer cognitive risk in MCI.     

Effect of tetramethylpyrazine on primary afferent transmission mediated by P2X3 receptor in neuropathic pain states

Neuropathic pain is the most difficult type of pain to treat. The P2X₃ receptors play a crucial role in facilitating pain transmission at peripheral and spinal sites. The present research investigated the effects of tetramethylpyrazine (TMP) on the primary afferent transmission induced by P2X₃ receptor in neuropathic pain states. Chronic constriction injury (CCI) model was adopted. Sprague–Dawley male rats (n = 30) had been randomly divided into normal saline (sham + NS) group (I), TMP group (II), sham group (III), CCI + TMP group (IV), and CCI group (V). Mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were measured and P2X₃ immunoreactivity in L4/L5 dorsal root ganglion (DRG) and spinal cord was detected by immunohistochemistry. The mechanical withdrawal threshold and thermal withdrawal latency in group V were lower than those in groups I–III or IV (p < 0.05), while P2X₃ receptor expression of L4/L5 DRG and spinal cord in group V was higher than those in groups I–III (p < 0.01) or group IV (p < 0.05). The mechanical withdrawal threshold, thermal withdrawal latency and P2X₃ immunoreactivity of L4/L5 DRG and spinal cord in group IV showed no significant difference compared with those in groups I, II or III (p > 0.05). The amplitudes of the currents in group V (CCI) were much larger than those obtained in other groups after application of same concentration adenosine 5′-triphosphate disodium (ATP) (p < 0.01). α,β-Methylene-ATP (α,β-meATP)-activated currents in DRG neurons of CCI rats were more obvious than those obtained in other group rats (p < 0.01). The results showed that TMP may inhibit the primary afferent transmission of neuropathic pain induced by P2X₃ receptor.     

Exercise and microstructural changes in the motor cortex of older adults

Exercise has been shown to counteract age‐related volume decreases in the human brain, and in this imaging study, we ask whether the same holds true for the microstructure of the cortex. Healthy older adults (n = 47, 65–90 years old) either exercised three times a week on a stationary bike or maintained their usual physical routine over a 12‐week period. Quantitative longitudinal relaxation rate (R₁) magnetic resonance imaging (MRI) maps were made at baseline and after the 12‐week intervention. R₁ is commonly taken to reflect cortical myelin density. The change in R₁ (ΔR₁) was significantly increased in a region of interest (ROI) in the primary motor cortex containing motor outputs to the leg musculature in the exercise group relative to the control group (p = .04). The change in R₁ in this ROI correlated with an increase in oxygen consumption at the first ventilatory threshold (VT1) (p = .04), a marker of improvement in submaximal aerobic performance. An exploratory analysis across the cortex suggested that the correlation was predominately confined to the leg representation in the motor cortex. This study suggests that microstructural declines in the cortex of older adults may be staved off by exercise.     

Measuring change in perceived well‐being of family caregivers: validation of the Spanish version of the Perceived Change Index (PCI‐S) in Chilean dementia caregivers

Objective

Few instruments evaluate family caregiver perceptions of challenges caring for persons with dementia and improvement or worsening in these areas. To address this measurement gap, we examine psychometric properties of a Spanish version of the 13‐item Perceived Change Index (PCI‐S), originally validated with English‐speaking caregivers.

Methods

Cross‐sectional study with 94 caregivers of persons with mild to moderate dementia in Chile. Interviews included caregiver demographics, burden, health perception, distress with behaviours, dementia severity, behavioural symptoms and functionality.

Results

Caregiver mean age was 55.9 (SD ± 14.14) years and mean years caregiving was 3 (SD ± 2.60). The scale had strong internal consistency (Cronbach α = 0.94), and inter‐observer consistency (CCI = 0.99; 95% CI = 0.95–0.99). Two factors were identified: Management skills (α = 0.89), and somatic well‐being and affects (α = 0.92), explaining 63% of scale variance. Significant associations supporting convergent validity were observed for PCI‐S and subscales with caregiver burden (p < 0.01), health perceptions (p < 0.01), depressive symptoms (p < 0.01) and distress with behaviours (p < 0.01); and in persons with dementia, functionality (p < 0.05), dementia severity (p < 0.05) and behavioural symptoms (p < 0.01) in expected directions. In logistic regression models, perceived worsening (PCI‐S and subscale scores) was associated with more behavioural symptoms (OR = 1.07; 95% CI = 1.03–1.15) and caregiver burden (OR = 1.48; 95% CI = 1.18–1.86); whereas perceived improvement was associated with higher physical functioning (OR = 0.95; 95% CI = 0.91–0.99) in persons with dementia. PCI‐S scores were not associated with socio‐demographic characteristics reflecting divergent validity.

Conclusions

Spanish version of the 13‐item Perceived Change Index and its two‐factor solution is a valid and reliable measure with clinical utility to detect improvement or worsening in caregivers concerning daily care challenges. Copyright © 2017 John Wiley & Sons, Ltd.     

Magnetic resonance imaging as a non-invasive tool to assess gastric emptying in mice

Background

Methods to study gastric emptying in rodents are time consuming or terminal, preventing repetitive assessment in the same animal. Magnetic resonance imaging (MRI) is a non-invasive technique increasingly used to investigate gastrointestinal function devoid of these shortcomings. Here, we evaluated MRI to measure gastric emptying in control animals and in two different models of gastroparesis.

Methods

Mice were scanned using a 9.4 Tesla MR scanner. Gastric volume was measured by delineating the stomach lumen area. Control mice were scanned every 30 min after ingestion of a 0.2 g meal and stomach volume was quantified. The ability of MRI to detect delayed gastric emptying was evaluated in models of morphine-induced gastroparesis and streptozotocin-induced diabetes.

Key Results

Magnetic resonance imaging reproducibly detected increased gastric volume following ingestion of a standard meal and progressively decreased with a half emptying time of 59 ± 5 min. Morphine significantly increased gastric volume measured at t = 120 min (saline: 20 ± 2 vs morphine: 34 ± 5 mm³; n = 8–10; p < 0.001) and increased half emptying time using the breath test (saline: 85 ± 22 vs morphine: 161 ± 46 min; n = 10; p < 0.001). In diabetic mice, gastric volume assessed by MRI at t = 60 min (control: 23 ± 2 mm³; n = 14 vs diabetic: 26 ± 5 mm³; n = 18; p = 0.014) but not at t = 120 min (control: 21 ± 3 mm³; n = 13 vs diabetic: 18 ± 5 mm³; n = 18; p = 0.115) was significantly increased compared to nondiabetic mice.

Conclusions and Inferences

Our data indicate that MRI is a reliable and reproducible tool to assess gastric emptying in mice and represents a useful technique to study gastroparesis in disease models or for evaluation of pharmacological compounds.     

Estimation of the Intelligence Quotient Using Wechsler Intelligence Scales in Children and Adolescents with Asperger Syndrome

Asperger syndrome (AS) patients show heterogeneous intelligence profiles and the validity of short forms for estimating intelligence has rarely been studied in this population. We analyzed the validity of Wechsler Intelligence Scale (WIS) short forms for estimating full-scale intelligence quotient (FSIQ) and assessing intelligence profiles in 29 AS patients. Only the Information and Block Design dyad meets the study criteria. No statistically significant differences were found between dyad scores and FSIQ scores (t(28) = 1.757; p = 0.09). The dyad has a high correlation with FSIQ, good percentage of variance explained (R ² = 0.591; p < 0.001), and high consistency with the FSIQ classification (χ ²(36) = 45.202; p = 0.14). Short forms with good predictive accuracy may not be accurate in clinical groups with atypical cognitive profiles such as AS patients.     

Superior longitudinal fasciculus and cognitive dysfunction in adolescents born preterm and at term

Aim To understand the relationship between cognition and white‐matter structure in adolescents born preterm without obvious brain injury. Methods Thirty‐two adolescents from a longitudinal study of child development were selected according to risk of developmental disorders at birth (born at term: eight males, five females; median age 16y 1mo, interquartile range 10mo; low risk preterm: four males, five females, median age 16y, range 4mo; high risk preterm: three males, seven females, median age 16y 2mo, range 1y 2mo) and reading ability (good: three males, eight females, median age 16y, range 7mo; average: six males, three females, median age 16y 10mo, range 1y; poor: six males, six females, median age 16y, range 6mo). Preterm birth was defined as a gestational age of 36 weeks or less and a birthweight of 1600g or less. All participants had normal clinical neuroimaging findings. We examined fractional anisotropy, radial diffusivity, and volume of three major white‐matter fasciculi. The relationship between structural measures and birth risk, hemisphere, and cognitive ability (attention, lexical and sublexical decoding, auditory phonological awareness, and processing speed) were analysed using mixed‐model regression. Results Left‐hemisphere superior longitudinal fasciculus (SLF) fractional anisotropy and radial diffusivity were linked to reading‐related skills (fractional anisotropy vs letter–word identification, r₍₃₀₎=?0.37, p<0.05; fractional anisotropy vs phoneme reversal, r₍₃₀₎=?0.34, p=0.05; radial diffusivity vs letter–word identification, r₍₃₀₎=0.31, p<0.10; radial diffusivity vs phoneme reversal, r₍₃₀₎=0.40, p<0.05), whereas right‐hemisphere SLF fractional anisotropy was related to attention skills (fractional anisotropy vs inattentiveness, r₍₃₀₎=?0.38, p<0.05). SLF volume decreased as these skills declined for adolescents born preterm (volume vs phoneme reversal, r₍₁₇₎=0.58, p<0.01; volume vs inattentiveness, r₍₁₇₎=?0.69, p<0.01), but not for those born at term. Interpretation The relationship between cognitive skills and SLF volume suggests that in adolescents born preterm, cryptic white‐matter injury may exist, possibly related to oligodendrocyte or axonal loss, despite normal clinical neuroimaging.     

Electrophysiological correlates of decision making impairment in multiple sclerosis

Although previous studies have shown that patients with multiple sclerosis (MS) may exhibit impaired decision making (DM), the specific neuro‐cognitive processes that underlie this deficiency remain unknown. Inefficient DM may occur due to poor option assessment or a deficit in the evaluation of choice outcomes. This study uses, for the first time, the event‐related potential (ERP) technique to analyze these DM subprocesses in patients with MS. Sixteen MS patients and nineteen control subjects performed a DM task based on the Iowa Gambling Task while a digital EEG was recorded. The P3b was analyzed as an index of option assessment, and both the feedback‐related negativity (FRN) and P3b were considered markers for choice outcome evaluation. We found that MS patients made a larger number of unfavorable choices during the DM task (P = 0.02), with no differences between groups for reaction times. There were no significant differences in P3b for option assessment between the groups. In the control group, the type of feedback (gain, loss, or nothing) modified the FRN (F = 3.72, P = 0.033) and the P3b (F = 3.15, P = 0.059). This effect was not observed in the MS group. Also, FRN latencies were shorter in the MS group compared to controls (P = 0.047). Finally, lesions in temporal regions revealed by MRI were associated with DM both in behavioral and electrophysiological terms. We conclude that the DM impairment of patients with MS may be due to a deficit in their evaluation of choice outcomes or a general alteration in emotional reactivity.     

Medial temporal lobe glutathione concentration in first episode psychosis: A H-MRS investigation

Glutathione (GSH) is implicated in the pathophysiology of schizophrenia. Previous brain spectroscopy studies, however, have been inconsistent, and there is little data available from first episode psychosis patients. This study compared brain GSH in a first episode cohort (n = 30) to controls (n = 18), using magnetic resonance spectroscopy (MRS), examining a temporal lobe voxel. Short-echo (TE 30 ms) acquisition proton MRS was performed on a 3T clinical magnetic resonance scanner. Comparison of the first-episode and control groups' GSH concentrations revealed a significant main effect of group (F_1,46 = 4.7, p = 0.035), but no main effect of hemisphere (F_1,46 = 2.3, p = 0.137) or group-by-side interactions (F_1,46 = 0.4, p = 0.513). Medial temporal lobe GSH concentrations in the first episode group were 22% higher than those in the control group. This study provides further evidence of significant perturbations in brain GSH in first episode psychosis, and supports a broader involvement of GSH in the pathophysiology of schizophrenia.     

Serum uric acid levels in patients with Parkinson's disease: Their relationship to treatment and disease duration

There is evidence to support that oxidative stress is increased in Parkinson's disease (PD) and contributes to degeneration of dopaminergic neurons. Uric acid (UA), a natural antioxidant in blood and brain tissue, scavenging superoxide, peroxynitrite and hydroxyl radical, was found reduced in the serum of PD patients. In addition low plasma uric acid (UA) levels have been associated with an increased risk of PD.

Objectives

The aim of our study was to investigate serum UA levels in PD patients compared with age-matched healthy controls and their possible relationship with several clinical parameters of PD and pharmaceutical treatment.

Patients and methods

We measured serum UA levels in 43 PD patients and 47 healthy volunteers, age and sex-matched. UA levels were correlated with disease duration, severity and treatment.

Results

Low UA levels were observed in PD patients compared with controls (p = 0.009). Age, Body Mass Index (BMI) and UPDRS III score did not significantly affect serum UA concentrations, whereas gender was found to contribute significantly to UA level (p < 0.000). Strong and significant inverse correlations of UA with disease duration (R_s = −0.397, p = 0.009) and daily levodopa dosage (R_p = −0.498, p = 0.026) were observed. These associations were significant for men (R_s = −0.441, p = 0.04 and R_s = −0.717, p = 0.03 respectively), but not for women (R_s = −0.221, p = 0.337 and R_s = −0.17, p = 0.966 respectively).

Conclusion

Our results suggest that there may be increased consumption of UA as a scavenger in PD, possibly heightened by dopaminergic drug treatment. Given the antioxidant properties of UA, manipulation of its concentrations should be investigated for potential therapeutic strategies of the disease.     

Motor dysfunction of the “non-affected” lower limb: a kinematic comparative study between hemiparetic stroke and total knee prosthesized patients

In patients with hemispheric stroke, abnormal motor performances are described also in the ipsilateral limbs. They may be due to a cortical reorganization in the unaffected hemisphere; moreover, also peripheral mechanisms may play a role. To explore this hypothesis, we studied motor performances in 15 patients with hemispheric stroke and in 14 patients with total knee arthroplasty, which have a reduced motility in the prosthesized leg. Using the unaffected leg, they performed five superimposed circular trajectories in a prefixed pathway on a computerized footboard, while looking at a marker on the computer screen. The average trace error was significantly different between the groups of patients and healthy subjects [F _(2,25) = 7.9; p = 0.003]; on the contrary, the test time execution did not vary significantly. In conclusion, both groups of patients showed abnormal motor performances of the unaffected leg; this result suggests a likely contribution of peripheral mechanisms.     

Thalamic white matter in multiple sclerosis: A combined diffusion‐tensor imaging and quantitative susceptibility mapping study

Thalamic white matter (WM) injury in multiple sclerosis (MS) remains relatively poorly understood. Combining multiple imaging modalities, sensitive to different tissue properties, may aid in further characterizing thalamic damage. Forty‐five MS patients and 17 demographically‐matched healthy controls (HC) were scanned with 3T MRI to obtain quantitative measures of diffusivity and magnetic susceptibility. Participants underwent cognitive evaluation with the Brief International Cognitive Assessment for Multiple Sclerosis battery. Tract‐based spatial statistics identified thalamic WM. Non‐parametric combination (NPC) analysis was used to perform joint inference on fractional anisotropy (FA), mean diffusivity (MD) and magnetic susceptibility measures. The association of surrounding WM lesions and thalamic WM pathology was investigated with lesion probability mapping. Compared to HCs, the greatest extent of thalamic WM damage was reflected by the combination of increased MD and decreased magnetic susceptibility (63.0% of thalamic WM, peak p = .001). Controlling for thalamic volume resulted in decreased FA and magnetic susceptibility (34.1%, peak p = .004) as showing the greatest extent. In MS patients, the most widespread association with information processing speed was found with the combination of MD and magnetic susceptibility (67.6%, peak p = .0005), although this was not evident after controlling for thalamic volume. For memory measures, MD alone yielded the most widespread associations (45.9%, peak p = .012 or 76.7%, peak p = .001), even after considering thalamic volume, albeit with smaller percentages. White matter lesions were related to decreased FA (peak p = .0063) and increased MD (peak p = .007), but not magnetic susceptibility, of thalamic WM. Our study highlights the complex nature of thalamic pathology in MS.     

Sex differences in the performance of cognitive tasks in a murine model of metabolic syndrome

The metabolic syndrome includes changes in blood glucose levels, arterial hypertension, triglycerides, dyslipidemia and central obesity. Countless reports have described the correlation between the metabolic syndrome and cognitive impairment. However, only a few reports have assessed cognitive impairment associated with the metabolic syndrome in animals of both sexes. For this purpose, Sprague‐Dawley male and female rats were fed either with a hypercaloric diet as model of the metabolic syndrome or with a standard chow diet as controls. Subsequently, spatial learning and memory (Morris water maze) as well as short‐ and long‐term memory (passive avoidance task) were evaluated. Body weight, blood pressure, triglycerides, and total cholesterol significantly increased (F(1, 36) = 94.89, p < .001) in rats fed with hypercaloric diet compared to control rats. Furthermore, cognitive impairment was observed in spatial learning and spatial memory on male rats but not on female rats fed with hypercaloric diet. In addition, a long‐term memory impairment was observed in both groups fed with hypercaloric diet in comparison to their respective control group (F(1, 32) = 10.61, p = .0027). Immunohistochemistry results showed no changes in the number of positive cells for NeuN, GFAP and Ox‐42. In males fed with a hypercaloric diet, a decrease in testosterone levels was observed, whereas estradiol levels decreased in females when compared with their respective control group (p < .0001). In this MetS animal model, metabolic and cognitive differences were observed in males and females, which demonstrates that sex hormones play a significant role in metabolic regulation and neuroprotection related to the CA1 region of the hippocampus.