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OBJECTIVE: Cognitive tests of inhibitory control show variable results for the differential diagnosis between behavioural variant of Frontotemporal Dementia (bvFTD) and Alzheimer's disease (AD). We compared the diagnostic accuracies of tests of inhibitory control and of a behavioural questionnaire, to distinguish bvFTD from AD. METHODS: Three groups of participants were enrolled: 27 bvFTD patients, 25 AD patients, and 24 healthy controls. Groups were matched for gender, education, and socio-economic level. Participants underwent a comprehensive neuropsychological assessment of inhibitory control, including Hayling Test, Stroop, the Five Digits Test (FDT) and the Delay Discounting Task (DDT). Caregivers completed the Barratt Impulsiveness Scale 11th version (BIS-11). RESULTS: bvFTD and AD groups showed no difference in the tasks of inhibitory control, while the caregiver questionnaire revealed that bvFTD patients were significantly more impulsive (BIS-11: bvFTD 76.1+9.5, AD 62.9+13, p < .001). CONCLUSIONS: Neuropsychological tests of inhibitory control failed to distinguish bvFTD from AD. On the contrary, impulsivity caregiver-completed questionnaire provided good distinction between bvFTD and AD. These results highlight the current limits of cognitive measures of inhibitory control for the differential diagnosis between bvFTD and AD, whereas questionnaire information appears more reliable and in line with clinical diagnostics.

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OBJECTIVE: Elderly people are at a high risk of developing vitamin D (VitD) deficiency due to both decreased intake and cutaneous synthesis. Most of the biological actions of VitD are mediated by the vitamin D receptor (VDR), which is present in neurons and glial cells of the hippocampus, and in the cortex and subcortical nuclei, essential areas for cognition. It is known that VDR gene polymorphisms may decrease the VDR affinity for VitD. Objective: The present study aimed to investigate the influence of VitD levels on cognitive decline in patients with dementia due to Alzheimer's disease (AD, n = 32) and mild cognitive impairment (MCI, n = 15) compared to cognitively healthy elderly (n = 24). METHODS: We also evaluated the association of VDR gene polymorphisms with cognitive disturbance. Methods: Four polymorphisms on the VDR gene were studied, namely, BsmI, ApaI, FokI and TaqI, by polymerase chain reaction-restriction fragment length polymorphism. Serum levels of 25-hydroxy vitamin D (25(OH)D) were determined by high performance liquid chromatography. RESULTS: Results: No significant difference in 25(OH)D levels or genotypic/allelic frequencies was observed between the groups. Deficiency of 25(OH)D was more frequently observed in women. The AA/AG genotypes of the BsmI polymorphism was associated with sufficient 25(OH)D levels, while the GG genotype of this same polymorphism was associated to insufficient levels in the cognitively-impaired group (individuals with AD or MCI). CONCLUSIONS: Conclusions: The data obtained do not confirm the relationship between reductions of VitD levels, polymorphisms in the VDR gene, and altered cognitive function in this sample. However, the data indicate that BsmI polymorphism in the VDR gene is associated with the VitD levels in individuals with cognitive decline.

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ABSTRACT Elderly people are at a high risk of developing vitamin D (VitD) deficiency due to both decreased intake and cutaneous synthesis. Most of the biological actions of VitD are mediated by the vitamin D receptor (VDR), which is present in neurons and glial cells of the hippocampus, and in the cortex and subcortical nuclei, essential areas for cognition. It is known that VDR gene polymorphisms may decrease the VDR affinity for VitD. Objective: The present study aimed to investigate the influence of VitD levels on cognitive decline in patients with dementia due to Alzheimer's disease (AD, n = 32) and mild cognitive impairment (MCI, n = 15) compared to cognitively healthy elderly (n = 24). We also evaluated the association of VDR gene polymorphisms with cognitive disturbance. Methods: Four polymorphisms on the VDR gene were studied, namely, BsmI, ApaI, FokI and TaqI, by polymerase chain reaction-restriction fragment length polymorphism. Serum levels of 25-hydroxy vitamin D (25(OH)D) were determined by high performance liquid chromatography. Results: No significant difference in 25(OH)D levels or genotypic/allelic frequencies was observed between the groups. Deficiency of 25(OH)D was more frequently observed in women. The AA/AG genotypes of the BsmI polymorphism was associated with sufficient 25(OH)D levels, while the GG genotype of this same polymorphism was associated to insufficient levels in the cognitively-impaired group (individuals with AD or MCI). Conclusions: The data obtained do not confirm the relationship between reductions of VitD levels, polymorphisms in the VDR gene, and altered cognitive function in this sample. However, the data indicate that BsmI polymorphism in the VDR gene is associated with the VitD levels in individuals with cognitive decline.

RESUMO Idosos apresentam risco elevado de desenvolverem deficiência de Vitamina D (VitD) devido à diminuição da ingestão e da síntese na pele. A maioria das ações biológicas da VitD é mediada pelo receptor da vitamina D (VDR), que está presente nos neurônios e células gliais do hipocampo, e no córtex e em núcleos subcorticais, áreas essenciais para a cognição. Sabe-se que polimorfismos do gene VDR podem diminuir a afinidade do VDR pela VitD. Objetivo: O presente estudo teve como objetivo investigar a influência dos níveis de VitD no declínio cognitivo em pacientes com demência devida à doença de Alzheimer (DA, n = 32) e comprometimento cognitivo leve (CCL, n = 15) em comparação a um grupo de idosos cognitivamente saudáveis (n = 24). Nós também avaliamos a associação entre polimorfimos no gene do receptor de VitD e as alterações cognitivas. Métodos: Quatro polimorfismos no gene VDR foram estudados, sendo BsmI, ApaI, FokI e TaqI, por PCR-RFLP. Os níveis séricos de 25-hidroxi vitamina D (25(OH)D) foram determinados por HPLC. Resultados: Não houve diferença significativa nos níveis de 25(OH)D ou nas frequências genotípicas / alélicas entre os grupos. Níveis deficientes de 25(OH)D foram mais frequentes nas mulheres. Os genótipos AA / AG do polimorfismo BsmI foram associados a níveis suficientes de 25(OH)D, enquanto o genótipo GG deste mesmo polimorfismo foi associado a níveis insuficientes no grupo com comprometimento cognitivo (em indivíduos com DA ou CCL). Conclusões: Os resultados obtidos não confirmam a relação entre redução dos níveis de VitD, polimorfismos no gene VDR e função cognitiva alterada nesta amostra. No entanto, os dados indicam que o polimorfismo BsmI no gene VDR está associado aos níveis de VitD em indivíduos com declínio cognitivo.

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Cognitive impairment, including mild cognitive impairment (MCI) and dementia, compromises the patients' cognitive abilities and, to different extents, to carry out daily activities, accompanied by personality and behavioral changes. Studies suggest that leptin, an adipokine, has a neuroprotective role against Alzheimer's disease (AD) and that cytokines are associated with inflammatory processes and dementia. This study aimed to evaluate serum leptin, hsCRP, IL-6 and TNF-α levels in a cognitive continuum group from normal to demential status, and to assess whether they correlates to Mini-Mental State Examination (MMSE) and Functional Assessment Staging (FAST) scores. Forty-three participants were included, of whom 12 with probable AD, 18 with MCI and 13 with no objective cognitive decline. Serum leptin and hsCRP levels were evaluated by immunoturbidimetric method, and IL-6 and TNF-α by ELISA. Higher TNF-α levels were found in individuals with FAST stages 1/2 and normal scores evaluated by MMSE. hsCRP levels were inversely correlated with FAST stages. No association with function or global cognition was observed for leptin and IL-6 levels. However, women presented higher leptin serum levels than men while lower leptin and IL-6 levels were observed in individuals aged ≥59 years. Our results suggest that TNF-α is associated with cognitive and functional decline and that inflammation could be a substrate of cognitive impairment at early clinical stages of dementia.

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This study was designed to determine whether the levels of renin-angiotensin system (RAS) components are associated with Alzheimer's disease (AD) pathology. Cerebrospinal fluid levels of Angiotensin (Ang) II, Ang-(1-7), angiotensin-converting enzyme (ACE), ACE2, Amyloid-ß (Aß)40, Aß42, total tau (hTau), and phospho-tau (pTau) were measured in 18 patients with AD and 10 controls. Patients with AD presented decreased levels of ACE when compared with controls. We found a significant positive correlation between ACE and Aß42 levels among patients. Our results strengthen the hypothesis that ACE is associated with Aß pathology in AD.

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INTRODUCTION: Executive dysfunction is a common symptom in neurodegenerative disorders and is in need of easy-to-apply screening tools that might identify it. The aims of the present study were to examine some of the psychometric characteristics of the Brazilian version of the INECO frontal screening (IFS), and to investigate its accuracy to diagnose executive dysfunction in dementia and its accuracy to differentiate Alzheimer disease (AD) from the behavioral variant of frontotemporal dementia (bvFTD). METHODS: Patients diagnosed with bvFTD (n=18) and AD (n=20), and 15 healthy controls completed a neuropsychological battery, the Neuropsychiatric Inventory, the Cornell Scale for Depression in Dementia, the Clinical Dementia Rating, and the IFS. RESULTS: The IFS had acceptable internal consistency (α=0.714) and was significantly correlated with general cognitive measures and with neuropsychological tests. The IFS had adequate accuracy to differentiate patients with dementia from healthy controls (AUC=0.768, cutoff=19.75, sensitivity=0.80, specificity=0.63), but low accuracy to differentiate bvFTD from AD (AUC=0.594, cutoff=16.75, sensitivity=0.667, specificity=0.600). CONCLUSION: The present study suggested that the IFS may be used to screen for executive dysfunction in dementia. Nonetheless, it should be used with caution in the differential diagnosis between AD and bvFTD.

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INTRODUCTION: Few studies on instruments for staging frontotemporal dementia (FTD) have been conducted. OBJECTIVE: The objective of this study was to analyze the factor structure, internal consistency, reliability, and convergent validity of the Brazilian version of the Frontotemporal Dementia Rating Scale (FTD-FRS). METHODS: A total of 97 individuals aged 40 years and above with >2 years' education took part in the study, 31 patients diagnosed with behavioral variant FTD (bvFTD), 8 patients with primary progressive aphasia, 28 with Alzheimer disease, 8 with mild cognitive impairment, and a control group of 22 healthy subjects. The FTD-FRS was completed by family members or caregivers, and Neurologists completed the 8-item Clinical Dementia Rating for Frontotemporal Lobar Degeneration (CDR-FTLD) scale (6 original domains plus Language and Behavior). The Alzheimer disease and FTD patients had equivalent disease severity level. RESULTS: The internal consistency of the FTD-FRS, estimated by Cronbach α, was 0.975 whereas test-retest reliability was 0.977. Scree plot and exploratory factor (Varimax rotation) analyses revealed the existence of 4 factors, with eigenvalues >1, which together explained 77.13% of the total variance with values of 1.28 to 17.52. The domains of the Brazilian version of the FTD-FRS scale correlated with the domains of the CDR-FTLD. CONCLUSIONS: The present study is the first to document the factorial structure of the FTD-FRS and its convergent validity with the CDR-FTLD. These tools are key to determine dementia severity in FTD. The Brazilian FTD-FRS demonstrated adequate psychometric properties for use in Brazil. This instrument may contribute to disease staging in FTD and may help to document intervention-related changes.

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OBJECTIVE: To investigate the frequency of the cytokine single nucleotide polymorphisms (SNPs) tumor necrosis factor (TNF)-α -308G > A, tumor growth factor (TGF)-ß1 codon +10C > T, TGF-ß1 codon +25G > C, interleukin (IL)-10 -1082A > G, IL-10 -819C > T, IL-10 -592C > A, IL-6 -174G > C, and IFN-γ +874T > A in a sample of healthy and cognitively impaired elderlies and to verify the probable association between these SNPs and cognitive and functional performance of subjects aged 75 years and above. METHODS: 259 Brazilian subjects were included, comprising 81 with cognitive impairment no dementia (CIND) and 54 demented seniors (together made up the cognitively impaired group, CI) and 124 age-matched and gender-matched cognitively healthy controls (CHS). The genotyping was performed by multiplex polymerase chain reaction. The cognitive performance was evaluated by Mini-Mental State Examination Brief Cognitive Screening Battery. The functional performance was accessed by Functional Activities Questionnaire. RESULTS: The CClower genotype of TGF-ß1 codon +25G > C was frequent in both patient groups. The TThigher genotype of INF-γ +874T > A was less frequent in the dementia group. IL-10 haplotypes of lower expression were more frequent among CIND and demented patients. In CI, individuals with genetic variants that produce higher expression of TGF-ß1, INF-γ, and IL-10 showed better normalized cognitive performance. Additionally, the Alower allele of INF-γ +874T > A was related to worse functional performance in CI, while the Alower allele of TNF-α -308G > A was associated with better cognitive and functional scores in the CIND group. CONCLUSIONS: Our findings suggest a potential role for certain cytokine SNPs in the development of CIND and dementia, which may influence the functional and cognitive performance of these patients. Copyright © 2016 John Wiley & Sons, Ltd.

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BACKGROUND: Mutations in GRN (progranulin) and MAPT (microtubule-associated protein tau) are among the most frequent causes of monogenic frontotemporal dementia (FTD), but data on the frequency of these mutations in regions such as Latin America are still lacking. OBJECTIVE: We aimed to investigate the frequencies of GRN and MAPT mutations in FTD cohorts from 2 Brazilian dementia research centers, the University of Sao Paulo and the Federal University of Minas Gerais medical schools. METHODS: We included 76 probands diagnosed with behavioral-variant FTD (n=55), semantic-variant Primary Progressive Aphasia (PPA) (n=11), or nonfluent-variant PPA (n=10). Twenty-five percent of the cohort had at least 1 relative affected with FTD. RESULTS: Mutations in GRN were identified in 7 probands, and in MAPT, in 2 probands. We identified 3 novel GRN mutations (p.Q130X, p.317Afs*12, and p.K259Afs*23) in patients diagnosed with nonfluent-variant PPA or behavioral-variant FTD. Plasma progranulin levels were measured and a cutoff value of 70 ng/mL was found, with 100% sensitivity and specificity to detect null GRN mutations. CONCLUSIONS: The frequency of GRN mutations was 9.6% and that of MAPT mutations was 7.1%. Among familial cases of FTD, the frequency of GRN mutations was 31.5% and that of MAPT mutations was 10.5%.

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