SQSTM1 Pro392Leu presenting as a corticobasal syndrome with progressive nonfluent aphasia.

Corticobasal syndrome is generally considered to be a sporadic condition. There are familial and isolated genetic cases, associated with GRN, MAPT, c9orf72 or PNRP variants. Some reports implicate other genes: LRRK2, CHMP2B, GBA, CYP27A1, PSEN1, APP, TARDBP and TBK1. Here, we report a case of a patient carrying a SQSTM1 Pro392Leu variant. We report a 57-year-old right-handed-woman with a history of progressive speech impairment, marked right side rigidity and bradykinesia, with rest tremor and stimulus sensitive myoclonus. She had predominantly right-sided apraxia. She had right side agraphestesia and astereognosis. MRI showed asymmetrical left frontotemporoparietal atrophy. DaTSCAN showed predominantly left involvement, PiB-PET was negative. CSF NfL was of 9356.5pg/mL. She carried a heterozygous variant P392L in SQSTM1. This case report expands the spectrum of phenotypes associated with SQSTM1 pathogenic variants. It also expands the list of genes associated with corticobasal syndrome, supporting the involvement of the ubiquitin-proteasome system in this condition.

Towards a neurocognitive profile in familial cerebral cavernous malformations.

BACKGROUND: Familial cerebral cavernous malformations (FCCM) is a rare autosomal dominant disease, characterized by vascular malformations that can lead to macro and microhemorrhages. The neurocognitive impact of FCCM is still underrecognized. METHODS: We report the clinical, neurocognitive, imaging and genetic data of a three generation family with FCCM. RESULTS: A 63-year-old man (proband) had progressive memory impairment since the last year. Neurologic exam was unremarkable. Brain MRI showed multiple large cavernomas (mainly in the pons, left temporal, and right temporo-parietal) and scattered microhemorrhages. Neuropsychological assessment mainly revealed left frontal and right temporo-parietal dysfunction. A 41-year-old daughter, presented with headache, vertigo and memory complaints in the last 2 years. Neurological examination revealed left central facial paralysis. Brain MRI showed two small right parietal and internal capsule cavernomas, as well as microhemorrhages. Neuropsychological assessment showed moderate temporal neocortical left dysfunction. A 34-year-old daughter had recurrent headache and memory complaints, with unremarkable neurological exam. Brain MRI revealed two large cavernomas (left fronto-orbitary and inferior temporal), with few microhemorrhages. Neuropsychological assessment was normal. A granddaughter had mild headaches and a small right cerebellar cavernoma, without microhemorrhages. Neuropsychological assessment showed mild temporal neocortical left dysfunction. A nonsense variant, c.55C > T; p.R19* generating a premature stop codon in CCM2 gene shared by all affected family members was identified. CONCLUSIONS: Neuropsychological evaluation showed that memory complaints and cognitive impairment could be an important unrecognized finding in FCCM. Its pathophysiological mechanisms are still unknown but the role of recurrent microhemorrhages could provide an interesting hypothesis.

Challenges in Genetic Diagnosis of Mitochondrial Diseases: What Can Functional Genomics' Studies Do?

INTRODUCTION: Mitochondrial oxidative phosphorylation (OXPHOS) diseases are challenging both from clinical and therapeutic perspectives. The advent of next-generation sequencing (NGS) boosted the discovery of new genetic defects affecting OXPHOS, with pathogenic variants identified in >350 genes to date [1]. However, in many patients, novel variants of unknown clinical significance are found. Subsequent functional studies may clarify its pathogenic consequences and modify the variant's classification, establishing a genetic diagnosis [2, 3]. METHODS: Analysis of data obtained from patients (P1-P5) with novel genetic causes and functional genomics' studies performed, namely OXPHOS respiratory/glycolytic rates (Seahorse XF), enzymatic activity and assembly (BN-page), protein levels (SDS-WB), single muscle fiber assay, NGS and bioinformatics. RESULTS/CASE REPORT: P1-Leigh syndrome (40y, male); Complex IV activity deficiency (full assembly absent), homozygous deletion (c.-11_13del, SURF1), not detected by NGS[2]. P2- Epileptic encephalopathy (8y, male); homozygous c.882-1G>A, FASTKD2; OXPHOS decrease; reduced FASTKD2 expression and abnormal respiratory/glycolytic rates. P3-Cardiomyopathy/ nephropathy (39y, male); c.29G>C, FASTKD2; OXPHOS decrease; reduced FASTKD2 levels. P4-CPEO (62y, female); multiple OXPHOS deficiency; mtDNA alterations (m.7486G>A, MTTS1; 4,977bp del); higher levels of mutant mtDNA alterations in COX-deficient fibers [3]. P5- Polyneuropathy (15y, female); heterozygous c.1437C>A, POLG; combined def. or normal OXPHOS activity/respiratory capacity (tissue variable), raised CI assembly; normal POLG levels. Also, proteins' expression levels were reduced (P1-4), confirming pathogenicity. In P5, data do not support pathogenicity. CONCLUSION: If specific functional results are similar to controls, one might inquire about the pathogenicity of the studied variant and more genetic or bioinformatics analyses and family investigations are needed. There are also limitations of NGS in mutation detection that Sanger sequencing can overcome (P1). When performed first, the OXPHOS activity may guide to genetic screening or interpretation, concordant to later assembly results. All cases were solved and data may be crucial for genetic counseling.

Montreal Cognitive Assessment in Mild Cognitive Impairment: Relationship with Cerebrospinal Fluid Biomarkers and Conversion to Dementia.

BACKGROUND: Mild cognitive impairment (MCI) is considered a prodromal state of dementia. Abnormal values of cerebrospinal fluid Alzheimer's disease biomarkers (CSF-AD-b) have been associated with a higher risk of conversion to dementia (due to Alzheimer's disease), but studies evaluating the ability of Montreal Cognitive Assessment (MoCA) in this task are lacking. OBJECTIVE: This study aims to investigate the relationship between MoCA and CSF-AD-b, as well as the ability of those tools to predict conversion to dementia. METHODS: Taking advantage of our MCI cohort with biological characterization on longitudinal follow-up (180 patients followed for 62.6 months during which 41.3% converted), we computed MoCA and MMSE z-scores, using Portuguese normative data. The performance in MoCA z-score was correlated with CSF-AD-b and the relative time to conversion and risk according to baseline characteristics were analyzed using Kaplan-Meier analysis and Cox regression models. RESULTS: MoCA z-scores were correlated with Aß42 (p = 0.026), t-tau (p = 0.033), and p-tau (p = 0.01). Impaired MMSE (p < 0.001) and MoCA z-scores (p = 0.019), decreased Aß42 (p < 0.001) and increased t-tau (p < 0.001) and p-tau (p < 0.001) were associated with shorter estimated time of conversion. Aß42 (p < 0.001) and MMSE z-scores (p = 0.029) were independent predictors of conversion. For those with at least 9 years of education, MoCA z-score (p = 0.004) (but not MMSE) was an independent predictor of conversion as well as Aß42. CONCLUSIONS: This study confirms the role of CSF-AD-b, namely Aß42, in predicting conversion from MCI to dementia and suggests the utility of MoCA in predicting conversion in highly educated subjects, supporting its use in the evaluation of MCI patients.

It's Never Too Late for a Diagnosis.

BACKGROUND: Zellweger spectrum disorder (ZSD) (OMIM#214100) is a phenotypic continuum ranging from severe to mild presentations. ZSD is now used in all individuals with a defect in one of the 13 ZSD-PEX genes, regardless of phenotype. Diagnosis can be suggested by abnormal levels of very long-chain fatty acids, phytanic acid, pristanic acid, plasmalogens, pipecolic acid, or bile acids. However, false negatives are frequent, mostly in older patients. Definite diagnosis is established in a proband with suggestive clinical findings by identification of biallelic pathogenic variants in one of the 13 ZSD-PEX genes. CASE REPORT: A 39-year-old female patient had a global development delay since her first year of life. Never developed oral language but had sphincter control and was able to walk and laugh. At 8 years old, she had her first seizure and lost sphincter control when she was 20 years old. At 28 years old, she had an episode of status epilepticus, with severe prostration and became bedridden. She is currently mute, without capacity for communication or motor control. She has no consanguineous parents, has a 35 year old brother with global developmental delay and their mother had a history of an abortion, without other relevant family history. Brain MRI of the patient revealed severe leukodystrophy mainly periventricular, bilateral and symmetric, and less prominent in the cerebellar white matter, with severe cerebral and corpus callosum atrophy. Molecular study with a leukodystrophy gene panela identified a homozygotic pathogenic variant on PEX 1 gene (NM_000466.3) - c.2528G>A (p.(Gly843Asp)), confirming the diagnosis of ZSD. CONCLUSION: Homozygosity for PEX1 p.Gly843Asp seems to be associated with an intermediate/milder ZSD phenotype,with survival until adulthood. Some patients develop progressive degeneration of CNS myelin, a leukodystrophy pattern, like this patient, which may lead to regression. This girl with ZSD had a rapid and severe loss of previous skills after a seizure. Even though there is no specific treatment for this disease, a correct diagnosiswas very important for the parents and for family genetic counselling.

Physical activity and exercise for the prevention and management of mild cognitive impairment and dementia: a collaborative international guideline.

BACKGROUND: Physical activity and exercise have been suggested as effective interventions for the prevention and management of mild cognitive impairment (MCI) and dementia, but there are no international guidelines. OBJECTIVES: To create a set of evidence- and expert consensus-based prevention and management recommendations regarding physical activity (any bodily movement produced by skeletal muscles that results in energy expenditure) and exercise (a subset of physical activity that is planned, structured, repetitive), applicable to a range of individuals from healthy older adults to those with MCI/dementia. METHODS: Guideline content was developed with input from several scientific and lay representatives' societies. A systematic search across multidisciplinary databases was carried out until October 2021. Recommendations for prevention and management were developed according to the GRADE and complemented by consensus statements from the expert panels. RECOMMENDATIONS: Physical activity may be considered for the primary prevention of dementia. In people with MCI there is continued uncertainty about the role of physical activity in slowing the conversion to dementia. Mind-body interventions have the greatest supporting evidence. In people with moderate dementia, exercise may be used for maintaining disability and cognition. All these recommendations were based on a very low/low certainty of evidence. CONCLUSIONS: Although the scientific evidence on the beneficial role of physical activity and exercise in preserving cognitive functions in subjects with normal cognition, MCI or dementia is inconclusive, this panel, composed of scientific societies and other stakeholders, recommends their implementation based on their beneficial effects on almost all facets of health.

SERAC1 Deficiency- A New Phenotype.

Introduction - SERAC1 deficiency phenotype range from MEGD(H)EL syndrome, the most severe, to juvenile complicated spastic paraplegia, to adult-onset dystonic features (in only one patient). The MEGD(H)EL syndrome is characterized by (3-methylglutaconic aciduria with deafness-dystonia, [hepatopathy], encephalopathy, and Leigh-like syndrome). Biochemical abnormalities: elevated urinary 3 - metilglutaconic and 3-metilglutaric acids, high lactate and alanine in serum. Diagnosis is confirmed when biallelic pathogenic variants in SERAC1 gene are found. Brain MRI: basal ganglia lesions and generalized atrophy. Results/Case report - A 30-year-old patient with a moderate intellectual disability, developed, since the age of 25, a progressive loss of previous capacities (hand dexterity, oral language), and later subacute generalized dystonic features. Currently he has spastic tetraparesis, dystonia, scoliosis and autistic behavior, with bilateral basal ganglia lesions on brain MRI. Genetic study revealed biallelic pathogenic variants in SERAC1 gene, confirm MEGD(H)EL. A 73 years old patient with cognitive impairment and progressive spastic tetraparesis had multiple periventricular T2 hyperintense lesions. She has a homozygotic SERAC1 variant NM_032861: exon4:c.T139A: p.F471 (rs112780453), considered benign. Biochemical study revealed elevated plasmatic alanine and urinary3-metilglutaconic and 3-metilglutaric acid. This profile is concordant with mitochondrial dysfunction and SERAC1 Deficit. Conclusion - The first patient has the clinical symptoms associated to the MEGD(H)EL syndrome, and the biochemical and genetic confirmation of the diagnosis, without reservations. However, in the second patient, the progressive paraparesis and cognitive impairment did not appear to be caused by multiple sclerosis nor subcortical vascular leukoencephalopathy (without vascular risk factors). The abnormal biochemical profile is suggestive of SERAC1 Deficiency, even without genetic confirmation. In what should we believe?

Serum Neurofilament Light Chain in the Diagnostic Evaluation of Patients with Cognitive Symptoms in the Neurological Consultation of a Tertiary Center.

Serum light-chain neurofilaments (sNfL) have been investigated as a potential minimally invasive biomarker that could help in the diagnosis of patients with cognitive symptoms. We assessed the correlation between sNfL and cerebrospinal fluid (CSF) biomarkers (sNfL versus CSF NfL, ρ= 0.70, p < 0.001), the performance of sNfL in distinguishing controls from patients (controls versus frontotemporal dementia, area under curve 0.86), and sNfL differences in mild cognitive impairment according to amyloid-ß (Aß) deposition (Aß versus non-Aß, p = 0.017). Our results support the role of this biomarker in the screening and risk stratification of patients followed in a neurological consultation of a tertiary center.

Adult-onset leukodystrophy with vanishing white matter: a case series of 19 patients.

BACKGROUND: Leukodystrophy with vanishing white matter (LVWM) is an autosomal recessive disease with typical pediatric-onset caused by mutations in one of the five EIF2B genes. Adult-onset (AO) cases are rare. METHODS: In this observational study, we reviewed clinical and laboratory information of the patients with AO-LVWM assessed at two referral centers in Italy and Portugal from Jan-2007 to Dec-2019. RESULTS: We identified 18 patients (13 females) with AO-LVWM caused by EIF2B5 or EIF2B3 mutations. Age of neurological onset ranged from 16 to 60 years, with follow-ups occurring from 2 to 37 years. Crucial symptoms were cognitive and motor decline. In three patients, stroke-like events were the first manifestation; in another, bladder dysfunction remained the main complaint across decades. Brain MRI showed white matter (WM) rarefaction in all cases, except two. Diffusion-weighted imaging documented focal hyperintensity in the acute stage of stroke-like events. 1H-spectroscopy primarily showed N-acetyl-aspartate reduction; 18fluorodeoxyglucose-PET revealed predominant frontoparietal hypometabolism; evoked potential studies demonstrated normal-to-reduced amplitudes; neuro-ophthalmological assessment showed neuroretinal thinning, and b-wave reduction on full-field electroretinogram. Interestingly, we found an additional patient with LVWM-compatible phenotype and monoallelic variants in two distinct eIF2B genes, EIF2B1 and EIF2B2. CONCLUSIONS: AO-LVWM presents varying clinical manifestations at onset, including stroke-like events. WM rarefaction is the most consistent diagnostic clue even in the latest onset cases. Spectroscopy and electrophysiological features are compatible with axon, rather than myelin, damage. Cerebral glucose metabolic abnormalities and retinal alterations can be present. LVWM might also be caused by a digenic inheritance affecting the eIF2B complex.

Blood biomarkers in mild cognitive impairment patients: Relationship between analytes and progression to Alzheimer disease dementia.

BACKGROUND AND PURPOSE: Blood-based biomarkers are promising tools for the diagnosis of Alzheimer disease (AD) at prodromal stages (mild cognitive impairment [MCI]) and are hoped to be implemented as screening tools for patients with cognitive complaints. In this work, we evaluated the potential of peripheral neurological biomarkers to predict progression to AD dementia and the relation between blood and cerebrospinal fluid (CSF) AD markers in MCI patients referred from a general neurological department. METHODS: A group of 106 MCI patients followed at the Neurology Department of Coimbra University Hospital was included. Data regarding baseline neuropsychological evaluation, CSF levels of amyloid ß 42 (Aß42), Aß40, total tau (t-Tau), and phosphorylated tau 181 (p-Tau181) were available for all the patients. Aß42, Aß40, t-Tau, p-Tau181, glial fibrillary acidic protein (GFAP), and neurofilament light chain (NfL) levels were determined in baseline stored serum and plasma samples by commercial SiMoA (Single Molecule Array) assays. Progression from MCI to AD dementia was assessed at follow-up (mean = 5.8 ± 3.4 years). RESULTS: At baseline, blood markers NfL, GFAP, and p-Tau181 were significantly increased in patients who progressed to AD at follow-up (p < 0.001). In contrast, plasma Aß42/40 ratio and t-Tau showed no significant differences between groups. NfL, GFAP, and p-Tau181 demonstrated good diagnostic accuracy to identify progression to AD dementia (area under the curve [AUC] = 0.81, 0.80, and 0.76, respectively), which improved when combined (AUC = 0.89). GFAP and p-Tau181 were correlated with CSF Aß42. Association of p-Tau181 with NfL was mediated by GFAP, with a significant indirect association of 88% of the total effect. CONCLUSIONS: Our findings highlight the potential of combining blood-based GFAP, NfL, and p-Tau181 to be applied as a prognostic tool in MCI.

Neuropsychological Assessment in the Distinction Between Biomarker Defined Frontal-Variant of Alzheimer's Disease and Behavioral-Variant of Frontotemporal Dementia.

BACKGROUND: Frontal-variant of Alzheimer's disease (fvAD) was purposed for patients with AD pathology that, despite the typical amnestic presentation, show early and progressive deterioration of behavior and executive functions, closely resembling the behavioral-variant of frontotemporal dementia (bvFTD). This leads to a challenging differential diagnosis where neuropsychological evaluation and in vivo pathological evidence are essential. OBJECTIVE: To evaluate the contribution of a comprehensive neuropsychological assessment (NP) battery in distinguishing between fvAD-dementia and bvFTD supported by cerebrospinal fluid (CSF) biomarkers. METHODS: We included 40 patients with a baseline NP profile with prominent early executive and/or behavioral dysfunction, who meet both diagnosis of bvFTD and fvAD-dementia, according to international criteria. All patients underwent comprehensive NP assessment and CSF-AD biomarker evaluation. Neuropsychological domains as well as clinical and sociodemographic features, and APOE genotype were compared between groups. RESULTS: 21 patients (52.5%) met the biological criteria for AD (decreased Aß42 together with increased T-tau or P-tau in CSF) and were therefore classified as fvAD (mean age was 64.57, with 47.6% female). There were no differences between groups regarding age/age-at-onset, gender, or educational level. Regarding neuropsychological profile, performances in language and memory functions were equivalent in both groups. Significant differences were found in visuo-constructional abilities (p = 0.004), Trail Making Test A (p < 0.001), and Raven's Colored Progressive Matrices (p = 0.019), with fvAD patients showing worst performances. CONCLUSION: In patients with an early prominent frontal profile, a higher impairment in attention and visuo-spatial functions, signaling additional right hemisphere fronto-parietal dysfunction, point towards a diagnosis of fvAD-dementia and may be useful in clinical practice.

Characterization of Progranulin Gene Mutations in Portuguese Patients with Frontotemporal Dementia.

In Portugal, heterozygous loss-of-function mutations in the progranulin (GRN) gene account for approximately half of the genetic mediated forms of frontotemporal dementia (FTD). GRN mutations reported thus far cause FTD through a haploinsufficiency disease mechanism. Herein, we aim to unveil the GRN mutation spectrum, investigated in 257 FTD patients and 19 family members from the central/north region of Portugal using sequencing methods. Seven different pathogenic variants were identified in 46 subjects including 40 patients (16%) and 6 relatives (32%). bvFTD was the most common clinical presentation among the GRN mutation patients, who showed a global pattern of moderate-to-severe frontotemporoparietal deficits in the neuropsychological evaluation. Interestingly, two mutations were novel (p.Thr238Profs*18, p.Leu354Profs*16), and five were previously described, although three of them only in the Portuguese population, suggesting a population-specific GRN mutational spectrum. The subjects harboring a GRN mutation showed a significant reduction in serum PGRN levels, supporting the pathogenic nature of these variants. This work broadens the mutation spectrum of GRN and the identification of the underlying GRN mutations provided an accurate genetic counselling and allowed the enrolment of subjects with GRN mutations (both asymptomatic and symptomatic) in ongoing clinical trials, which is essential to test new drugs for the disease.

Portuguese version of the CDR plus NACC FTLD: Validation studies.

Introduction: The CDR Dementia Staging Instrument PLUS National Alzheimer's Coordinating Center (CDR plus NACC FTLD) was developed by adding to the standard CDR two extra domains focused on the main features of frontotemporal lobar degeneration (FTLD): language and behavior/personality. We intended to perform the validation studies for the European-Portuguese population. Methods: A total of 105 participants matched for age, education, and disease staging (35 bvFTD, 35 AD, and 35 controls) were included. A translated-version of the CDR and the two added domains was administered by a neuropsychologist who was blinded to the diagnosis. Results: The bvFTD group had higher baseline CDR plus NACC FTLD scores compared to the AD and controls. Only the sum-of-boxes (SB) score, the behavior/personality, and language domains were able to distinguish between clinical groups. Logistic regression analyses showed that adding the behavior/personality domain with or without language significantly enhanced the discriminating ability. Discussion: Results show that the CDR plus NACC FTLD is a reliable tool in the diagnostic process of bvFTD patients and has an added value in distinguishing them from patients with AD.

How Reliable Are Ultra-Short-Term HRV Measurements during Cognitively Demanding Tasks?

Ultra-short-term HRV features assess minor autonomous nervous system variations such as variations resulting from cognitive stress peaks during demanding tasks. Several studies compare ultra-short-term and short-term HRV measurements to investigate their reliability. However, existing experiments are conducted in low cognitively demanding environments. In this paper, we propose to evaluate these measurements' reliability under cognitively demanding tasks using a near real-life setting. For this purpose, we selected 31 HRV features, extracted from data collected from 21 programmers performing code comprehension, and compared them across 18 different time frames, ranging from 3 min to 10 s. Statistical significance and correlation tests were performed between the features extracted using the larger window (3 min) and the same features extracted with the other 17 time frames. We paired these analyses with Bland-Altman plots to inspect how the extraction window size affects the HRV features. The main results show 13 features that presented at least 50% correlation when using 60-second windows. The HF and mNN features achieved around 50% correlation using a 30-second window. The 30-second window was the smallest time frame considered to have reliable measurements. Furthermore, the mNN feature proved to be quite robust to the shortening of the time resolution.

Alzheimer's Disease Diagnosis Based on the Amyloid, Tau, and Neurodegeneration Scheme (ATN) in a Real-Life Multicenter Cohort of General Neurological Centers.

BACKGROUND: The ATN scheme was proposed as an unbiased biological characterization of the Alzheimer's disease (AD) spectrum, grouping biomarkers into three categories: brain Amyloidosis-A, Tauopathy-T, Neurodegeneration-N. Although this scheme was mainly recommended for research, it is relevant for diagnosis. OBJECTIVE: To evaluate the ATN scheme performance in real-life cohorts reflecting the inflow of patients with cognitive complaints and different underlying disorders in general neurological centers. METHODS: We included patients (n = 1,128) from six centers with their core cerebrospinal fluid-AD biomarkers analyzed centrally. A was assessed through Aß42/Aß40, T through pTau-181, and N through tTau. Association between demographic features, clinical diagnosis at baseline/follow-up and ATN profiles was assessed. RESULTS: The prevalence of ATN categories was: A-T-N-: 28.3%; AD continuum (A + T-/+N-/+): 47.8%; non-AD (A- plus T or/and N+): 23.9%. ATN profiles prevalence was strongly influenced by age, showing differences according to gender, APOE genotype, and cognitive status. At baseline, 74.6% of patients classified as AD fell in the AD continuum, decreasing to 47.4% in mild cognitive impairment and 42.3% in other neurodegenerative conditions. At follow-up, 41% of patients changed diagnosis, and 92% of patients that changed to AD were classified within the AD continuum. A + was the best individual marker for predicting a final AD diagnosis, and the combinations A + T+ (irrespective of N) and A + T+N+ had the highest overall accuracy (83%). CONCLUSION: The ATN scheme is useful to guide AD diagnosis in real-life neurological centers settings. However, it shows a lack of accuracy for patients with other types of dementia. In such cases, the inclusion of other markers specific for non-AD proteinopathies could be an important aid to the differential diagnosis.

Late onset neuromyelitis optica spectrum disorders (LONMOSD) from a nationwide Portuguese study: Anti-AQP4 positive, anti-MOG positive and seronegative subgroups.

INTRODUCTION: Several neuroimmunological disorders have distinct phenotypes according to the age of onset, as in multiple sclerosis or myasthenia gravis. It is also described that late onset NMOSD (LONMOSD) has a different phenotype. OBJECTIVE: To describe the clinical/demographic characteristics of the LONMOSD and distinguish them from those with early onset (EONMOSD). METHODS: From a nationwide Portuguese NMOSD study we analyzed the clinical/demographic characteristics of the LONMOSD. RESULTS: From the 180 Portuguese patients 45 had disease onset after 50 years old, 80% were female. 23 had anti-AQP4 antibodies (51.1%), 13 anti-MOG antibodies (28.9%) and 9 were double seronegative (20.0%). The most common presenting phenotypes in LONMOSD were transverse myelitis (53.3%) and optic neuritis (26.7%), without difference from EONMOSD (p = 0.074). The mean EDSS for LONMOSD was 6.0 (SD=2.8), after a mean follow-up time of 4.58 (SD=4.47) years, which was significantly greater than the mean EDSS of EONMOSD (3.25, SD=1.80)(p = 0.022). Anti-AQP4 antibodies positive LONMOSD patients had increased disability compared to anti-MOG antibodies positive LONMOSD (p = 0.022). The survival analysis showed a reduced time to use a cane for LONMOSD, irrespective of serostatus (p<0.001). CONCLUSIONS: LONMOSD has increased disability and faster progression, despite no differences in the presenting clinical phenotype were seen in our cohort.

Software Bug Detection Causes a Shift From Bottom-Up to Top-Down Effective Connectivity Involving the Insula Within the Error-Monitoring Network.

The neural correlates of software programming skills have been the target of an increasing number of studies in the past few years. Those studies focused on error-monitoring during software code inspection. Others have studied task-related cognitive load as measured by distinct neurophysiological measures. Most studies addressed only syntax errors (shallow level of code monitoring). However, a recent functional MRI (fMRI) study suggested a pivotal role of the insula during error-monitoring when challenging deep-level analysis of code inspection was required. This raised the hypothesis that the insula is causally involved in deep error-monitoring. To confirm this hypothesis, we carried out a new fMRI study where participants performed a deep source-code comprehension task that included error-monitoring to detect bugs in the code. The generality of our paradigm was enhanced by comparison with a variety of tasks related to text reading and bugless source-code understanding. Healthy adult programmers (N = 21) participated in this 3T fMRI experiment. The activation maps evoked by error-related events confirmed significant activations in the insula [p(Bonferroni) < 0.05]. Importantly, a posterior-to-anterior causality shift was observed concerning the role of the insula: in the absence of error, causal directions were mainly bottom-up, whereas, in their presence, the strong causal top-down effects from frontal regions, in particular, the anterior cingulate cortex was observed.

Lewy body dementia is associated with an increased risk of atrial fibrillation: A case-control study.

BACKGROUND: Lewy bodies are a hallmark of Dementia with Lewy Bodies. They can also be found in the sinoatrial node and may be associated with heart disease. OBJECTIVES: We aimed to investigate a possible association between Lewy Body dementia and atrial fibrillation. METHODS: We performed a case-control study based on our centre's cohort of degenerative dementia (Dementia with Lewy Bodies and Alzheimer's disease) patients. The possible association between Lewy Body dementia and atrial fibrillation was studied through a binomial logistic regression, which adjusted for comorbidity data. RESULTS: We included 461 patients. 45 of the 398 (11.3%) with Alzheimer's disease and 14 of the 63 with Dementia with Lewy Bodies (22.2%) had atrial fibrillation. Heart failure (OR = 3.345, 95%CI = [1.618, 6.916], p = 0.001), hypertension (OR = 2.547, 95%CI = [1,137, 5.703], p = 0.023), stroke (OR = 2.274, 95%CI = [1.013, 5.103], p = 0.046) and Dementia with Lewy Bodies (OR = 2.536, 95%CI = [1.105, 5.822], p = 0.028) were associated with atrial fibrillation. CONCLUSIONS: We found an association between Dementia with Lewy bodies and Atrial Fibrillation.

Rare variants in TP73 in a frontotemporal dementia cohort link this gene with primary progressive aphasia phenotypes.

BACKGROUND AND PURPOSE: TP73 was recently reported to cause amyotrophic lateral sclerosis (ALS). ALS and frontotemporal dementia (FTD) are considered to form part of a continuum. We aimed to investigate whether TP73 variants may be associated with FTD. METHODS: We studied a thoroughly investigated cohort of 65 Portuguese patients with frontotemporal dementia using whole-exome sequencing. The patients had no other known genetic cause for their disease (C9orf72 expansion was also excluded). RESULTS: Of the 65 patients studied, two had rare variants in TP73 (p.Gly605Ser and p.Arg347Trp). Both variants had minor allele frequency <0.001 and were predicted to be pathogenic in silico. The two patients displayed a phenotype that included predominant language impairment, suggestive of non-fluent progressive aphasia. CONCLUSION: We show that two thoroughly studied patients without other known genetic changes harbored TP73 rare variants, which are pathogenic in silico. This adds evidence to support the role of TP73 in the ALS-FTD spectrum, especially in primary progressive aphasia cases.