TDP-43 nuclear condensation and neurodegenerative proteinopathies.

RNA-binding proteins (RBPs) can undergo phase separation and form condensates, processes that, in turn, can be critical for their functionality. In a recent study, Huang, Ellis, and colleagues show that cellular stress can trigger transient alterations in nuclear TAR DNA-binding protein 43 (TDP-43), leading to changes crucial for proper neuronal function. These findings have implications for understanding neurological TDP-43 proteinopathies.

Single-domain magnetic particles with motion behavior under electromagnetic AC and DC fields are a fatal cargo in Metropolitan Mexico City pediatric and young adult early Alzheimer, Parkinson, frontotemporal lobar degeneration and amyotrophic lateral sclerosis and in ALS patients.

Metropolitan Mexico City (MMC) children and young adults exhibit overlapping Alzheimer and Parkinsons' diseases (AD, PD) and TAR DNA-binding protein 43 pathology with magnetic ultrafine particulate matter (UFPM) and industrial nanoparticles (NPs). We studied magnetophoresis, electron microscopy and energy-dispersive X-ray spectrometry in 203 brain samples from 14 children, 27 adults, and 27 ALS cases/controls. Saturation isothermal remanent magnetization (SIRM), capturing magnetically unstable FeNPs ~ 20nm, was higher in caudate, thalamus, hippocampus, putamen, and motor regions with subcortical vs. cortical higher SIRM in MMC ≤ 40y. Motion behavior was associated with magnetic exposures 25-100 mT and children exhibited IRM saturated curves at 50-300 mT associated to change in NPs position and/or orientation in situ. Targeted magnetic profiles moving under AC/AD magnetic fields could distinguish ALS vs. controls. Motor neuron magnetic NPs accumulation potentially interferes with action potentials, ion channels, nuclear pores and enhances the membrane insertion process when coated with lipopolysaccharides. TEM and EDX showed 7-20 nm NP Fe, Ti, Co, Ni, V, Hg, W, Al, Zn, Ag, Si, S, Br, Ce, La, and Pr in abnormal neural and vascular organelles. Brain accumulation of magnetic unstable particles start in childhood and cytotoxic, hyperthermia, free radical formation, and NPs motion associated to 30-50 µT (DC magnetic fields) are critical given ubiquitous electric and magnetic fields exposures could induce motion behavior and neural damage. Magnetic UFPM/NPs are a fatal brain cargo in children's brains, and a preventable AD, PD, FTLD, ALS environmental threat. Billions of people are at risk. We are clearly poisoning ourselves.

Is Montreal Cognitive Assessment a valuable test for the differentiation of Alzheimer's disease, frontotemporal dementia, dementia with Lewy body, and vascular dementia?

Dementia is one of the growing diseases in the world and has different types based on its definition. The Montreal Cognitive Assessment (MoCA) test has been employed to screen patients with dementia, cognitive impairment, and disruption of daily activities. Objective: This study examined the diagnostic value of the total MoCA score and its subscores in differentiating Alzheimer's disease (AD), frontotemporal dementia (FTD), dementia with Lewy body (DLB), and vascular dementia (VaD). Methods: A total of 241 patients (AD=110, FTD=90, DLB=28, and VaD=13) and 59 healthy persons, who were referred to a dementia clinic with memory impairment in Firoozgar Hospital, were included in this study. MoCA tests were performed in all patients and normal persons. Results: By using the receiver operating characteristic (ROC) curve and measuring the area under the curve (AUC) for the total MoCA score in each group, AUC was 0.616, 0.681, 0.6117, and 0.583 for differentiating AD, FTD, DLB, and VaD patients, respectively. Among the groups, just the VaD group showed no significant usefulness in using the total MoCA score to differentiate it. To compare MoCA subscores, AD patients had higher scores in digit span, literal fluency, and abstraction but lower delayed recall scores compared with FTD patients. Conclusion: The total MoCA score and its subscores could not differentiate people with different types of dementia in the setting of screening.

A demência é uma das doenças que mais cresce no mundo e possui diferentes tipos de acordo com sua definição. O teste de Avaliação Cognitiva de Montreal (Montreal Cognitive Assessment ­ MoCA) tem sido empregado para a triagem de pacientes com demência, comprometimento cognitivo e perturbação das atividades diárias. Objetivo: Este estudo examinou o valor diagnóstico da pontuação total do MoCA e seus subescores na diferenciação entre doença de Alzheimer (DA), demência frontotempotal (DFT), demência com corpos de Lewy (DCL) e demência vascular (DV). Métodos: Este estudo incluiu 241 pacientes (DA=110, DFT=90, DCL=28 e DV=13) e 59 pessoas saudáveis, encaminhados à clínica de demência com comprometimento de memória no Hospital Firoozgar. O teste MoCA foi realizado em todos os pacientes e pessoas normais. Resultados: Usando a curva característica de operação do receptor (ROC) e medindo a área sob a curva (AUC) para a pontuação total do MoCA em cada grupo, a AUC foi de 0,616, 0,681, 0,6117 e 0,583 para diferenciar pacientes com DA, DFT, DCL e DV, respectivamente. Entre os grupos, apenas o grupo DV não mostrou utilidade significativa no uso do escore total do MoCA para diferenciá-lo. Para comparar os subescores do MoCA, os pacientes com DA tiveram pontuações mais altas em amplitude de dígitos, fluência verbal e abstração, mas menor pontuação de recordação tardia em comparação com pacientes com DFT. Conclusão: A pontuação total do MoCA e seus subescores não conseguiram diferenciar pessoas com diferentes tipos de demência no contexto da triagem.

Improved Accuracy of the Addenbrooke's Cognitive Examination-Revised in the Diagnosis of Mild Cognitive Impairment, Mild Dementia Due to Alzheimer's Disease and Behavioral Variant Frontotemporal Dementia Using Mokken Scale Analysis.

Background: The Addenbrooke's Cognitive Examination-Revised (ACE-R) is an accessible cognitive tool that supports the early detection of mild cognitive impairment (MCI), Alzheimer's disease (AD), and behavioral variant frontotemporal dementia (bvFTD). Objective: To investigate the diagnostic efficacy of the ACE-R in MCI, AD, and bvFTD through the identification of novel coefficients for differentiation between these diseases. Methods: We assessed 387 individuals: 102 mild AD, 37 mild bvFTD, 87 with amnestic MCI patients, and 161 cognitively unimpaired controls. The Mokken scaling technique facilitated the extraction out of the 26 ACE-R items that exhibited a common latent trait, thereby generating the Mokken scales for the AD group and the MCI group. Subsequently, we performed logistic regression, integrating each Mokken scales with sociodemographic factors, to differentiate between AD and bvFTD, as well as between AD or MCI and control groups. Ultimately, the Receiver Operating Characteristic curve analysis was employed to assess the efficacy of the coefficient's discrimination. Results: The AD-specific Mokken scale (AD-MokACE-R) versus bvFTD exhibited an Area Under the Curve (AUC) of 0.922 (88% sensitivity and specificity). The AD-MokACE-R versus controls achieved an AUC of 0.968 (93% sensitivity, 94% specificity). The MCI-specific scale (MCI-MokACE-R) versus controls demonstrated an AUC of 0.859 (78% sensitivity, 79% specificity). Conclusions: The ACE-R's capacity is enhanced through statistical methods and demographic integration, allowing for accurate differentiation between AD and bvFTD, as well as between MCI and controls. This new method not only reinforces its clinical value in early diagnosis but also surpasses traditional approaches noted in prior studies.

Allostatic Interoceptive Overload Across Psychiatric and Neurological Conditions.

Emerging theories emphasize the crucial role of allostasis (anticipatory and adaptive regulation of the body's biological processes) and interoception (integration, anticipation, and regulation of internal bodily states) in adjusting physiological responses to environmental and bodily demands. In this review, we explore the disruptions in integrated allostatic interoceptive mechanisms in psychiatric and neurological disorders, including anxiety, depression, Alzheimer's disease, and frontotemporal dementia. We assess the biological mechanisms associated with allostatic interoception, including whole-body cascades, brain structure and function of the allostatic interoceptive network, heart-brain interactions, respiratory-brain interactions, the gut-brain-microbiota axis, peripheral biological processes (inflammatory, immune), and epigenetic pathways. These processes span psychiatric and neurological conditions and call for developing dimensional and transnosological frameworks. We synthesize new pathways to understand how allostatic interoceptive processes modulate interactions between environmental demands and biological functions in brain disorders. We discuss current limitations of the framework and future transdisciplinary developments. This review opens a new research agenda for understanding how allostatic interoception involves brain predictive coding in psychiatry and neurology, allowing for better clinical application and the development of new therapeutic interventions.

Influence of Behavioral and Psychological Symptoms on Caregiver Burden for Different Types of Dementia: Clinical Experience in Lima, Peru.

INTRODUCTION: People caring for patients with dementia are prone to suffering from burden. Behavioral and psychological symptoms of dementia (BPSD) may have an impact on caregiver burden. In Latin American countries, there is a lack of research on caregiver burden. We aimed to determine which BPSD have the greatest impact on caregiver burden among Peruvian patients with dementia and to compare the effects of BPSD on caregiver burden across different types of dementia. METHODS: A cross-sectional study was conducted on 231 patients living with Alzheimer's dementia (AD), behavioral variant frontotemporal dementia (bvFTD), dementia with Lewy bodies (DLB), and vascular dementia (VD) and their caregivers who attended a Peruvian memory clinic. BPSD were assessed with the Neuropsychiatric Inventory (NPI). Caregiver burden was assessed with the Zarit Burden Inventory. We used analysis of variance to compare the AD, bvFTD, DLB, and VD groups. Correlations between Zarit Burden Inventory and NPI subscale scores were assessed with Spearman's correlation. RESULTS: DLB caregivers had significantly higher levels of burden than the other patient groups (p < 0.05) and higher total NPI scores than caregivers for other patient groups (p < 0.05). bvFTD caregivers had significantly higher total NPI scores than AD and VD caregivers (p < 0.05). Hallucinations, aberrant motor behavior, and apathy were the symptoms most significantly correlated with caregiver burden in those caring for DLB, bvFTD, and AD patients, respectively. CONCLUSION: Neuropsychiatric symptoms are higher in DLB caregivers. Hallucinations, aberrant motor behavior, and apathy are the main symptoms correlated with burden.

Right versus left temporal lobe semiology in dementia: Lessons from two cases with focal frontotemporal dementia syndromes.

Focal atrophy of the left anterior temporal lobe has been associated with the semantic type of primary progressive aphasia evolving to semantic dementia. In contrast, focal atrophy of the right temporal lobe has more recently been described as a controverse entity reported as the right temporal variant of FTD. We describe two cases of FTD dementia syndromes: in Case 1, atrophy of the right temporal lobe led to significant behavioural impairment and difficulties in recognizing known people. In Case 2, atrophy of the left temporal lobe was associated with severe aggressive, ritualistic behaviour and aphasia.

The contribution of Alois Alzheimer and Oskar Fischer to the understanding of Pick's complex - (Historical Note) / A contribuição de Alois Alzheimer e Oskar Fischer para a compreensão do complexo de Pick - (Nota Histórica)

Arnold Pick described a series of cases with progressive aphasia, behavioural disorders, and dementia. The post-mortem examination revealed on macroscopy, beside diffuse brain atrophy, also circumscribed (lobar) atrophy of the temporal and/or frontal lobes. The histopathology was not provided. Such kind of cases were soon named after the author, being known for a time as 'Pick's disease', coming to constitute a new nosological group. A time later after the original description, Alois Alzheimer and Oskar Fischer completed microscopic examination of similar cases, where the first author found, on silver impregnation, spheric neuronal inclusions, he named 'argentophilic ball' inclusions, while the second one identified complex cortical changes he named 'spongiform cortical wasting', and additionally a type of swollen cell that was named 'ballooned neuron'. Such microscopic changes became the first histopathological markers of this group of diseases.

Arnold Pick descreveu uma série de casos apresentando, de modo progressivo, afasia, transtornos de comportamento e demência. O exame pós-morte revelou à macroscopia, além de atrofia cerebral difusa, também atrofia circunscrita (lobar) dos lobos temporais e/ou frontais. A histopatologia não foi fornecida. Tal tipo de casos foi logo denominado segundo o autor, sendo conhecido por um período como 'doença de Pick', vindo a constituir um novo grupo nosológico. Algum tempo após a discrição original, Alois Alzheimer e Oskar Fischer perfizeram exame microscópio de casos semelhantes, onde o primeiro autor encontrou inclusões neuronais esféricas à impregnação pela prata, que denominou de 'bola argirofílica', enquanto o segundo identificou alterações corticais complexas às quais denominou 'perda cortical espongiforme', além de um tipo de célula tumefeita que chamou de 'neurônio balonizado'. Tais alterações microscópicas tornaram-se os primeiros marcadores histopatológicos desse grupo de doenças.

A comprehensive review on frontotemporal dementia: its impact on language, speech and behavior.

Frontotemporal dementia (FTD) is a progressive neurodegenerative disorder defined by the selective deterioration of the frontal and temporal lobes of the brain. This comprehensive review explored the effect of FTD on language, speech, and behavior. Early symptoms include difficulty in word finding, reduced speech output, and comprehension deficits, often leading to aphasia. The study discussed the profound behavioral changes observed in FTD patients, including apathy, disinhibition, compulsive behaviors, and loss of empathy, the importance of an accurate and early diagnosis, and its challenges. We even reviewed the potential for targeted therapies and the essential role of multidisciplinary care in managing the language, speech, and behavioral aspects of FTD. By examining objective data and comprehensive research on the subject, this study offers valuable insights into FTD's profound effects on language, speech, and behavior, assisting in improved clinical management and potential therapeutic strategies for this devastating condition.

A demência frontotemporal (DFT) é uma doença neurodegenerativa progressiva definida pela deterioração seletiva dos lobos frontal e temporal do cérebro. Esta revisão abrangente explorou o efeito da DFT na linguagem, na fala e no comportamento. Os primeiros sintomas incluem dificuldade em encontrar palavras, redução da produção de fala e déficits de compreensão, muitas vezes levando à afasia. A revisão discutiu as profundas mudanças comportamentais observadas em pacientes com DFT, incluindo apatia, desinibição, comportamentos compulsivos e perda de empatia, a importância de um diagnóstico preciso e precoce e seus desafios. Também foi revisado o potencial para terapias direcionadas e o papel essencial do cuidado multidisciplinar no gerenciamento dos aspectos de linguagem, fala e comportamentais da DFT. Ao examinar os dados objetivos e a pesquisa abrangente sobre o assunto, esta revisão oferece insights valiosos sobre os efeitos profundos da DFT na linguagem, na fala e no comportamento, auxiliando no melhor manejo clínico e em possíveis estratégias terapêuticas para essa condição devastadora.

Viscous dynamics associated with hypoexcitation and structural disintegration in neurodegeneration via generative whole-brain modeling.

INTRODUCTION: Alzheimer's disease (AD) and behavioral variant frontotemporal dementia (bvFTD) lack mechanistic biophysical modeling in diverse, underrepresented populations. Electroencephalography (EEG) is a high temporal resolution, cost-effective technique for studying dementia globally, but lacks mechanistic models and produces non-replicable results. METHODS: We developed a generative whole-brain model that combines EEG source-level metaconnectivity, anatomical priors, and a perturbational approach. This model was applied to Global South participants (AD, bvFTD, and healthy controls). RESULTS: Metaconnectivity outperformed pairwise connectivity and revealed more viscous dynamics in patients, with altered metaconnectivity patterns associated with multimodal disease presentation. The biophysical model showed that connectome disintegration and hypoexcitability triggered altered metaconnectivity dynamics and identified critical regions for brain stimulation. We replicated the main results in a second subset of participants for validation with unharmonized, heterogeneous recording settings. DISCUSSION: The results provide a novel agenda for developing mechanistic model-inspired characterization and therapies in clinical, translational, and computational neuroscience settings.

The role of brain perfusion SPECT in the diagnosis of frontotemporal dementia: A systematic review.

BACKGROUND AND PURPOSE: Frontotemporal dementia (FTD) is the second most common cause of presenile dementia. The clinical distinction between FTD, Alzheimer's disease (AD), and other dementias is a clinical challenge. Brain perfusion SPECT may contribute to the diagnosis of FTD, but its value is unclear. METHODS: We performed a systematic review to investigate the diagnostic accuracy of the brain SPECT in (1) distinguishing FTD from AD and other dementias and (2) differentiating FTD variants. RESULTS: Overall, 391 studies were retrieved on the initial search and 35 studies composed the final selection, comprising a total number of 3142 participants of which 1029 had FTD. The sensitivity and the specificity for the differential diagnosis of FTD versus AD ranged from 56% to 88% and from 51% to 93%, respectively. SPECT is not superior to the clinical method of diagnosis, but the combination of SPECT with clinical data seems to improve the diagnostic accuracy. CONCLUSION: Brain perfusion SPECT has a limited value in the diagnostic framework of FTD. SPECT can be performed when FDG-PET is not available. SPECT is recommended only for selected cases when the diagnosis is challenging using conventional methods.

A comprehensive review on frontotemporal dementia: its impact on language, speech and behavior / Uma revisão abrangente sobre demência frontotemporal: seu impacto na linguagem, fala e comportamento

ABSTRACT. Frontotemporal dementia (FTD) is a progressive neurodegenerative disorder defined by the selective deterioration of the frontal and temporal lobes of the brain. This comprehensive review explored the effect of FTD on language, speech, and behavior. Early symptoms include difficulty in word finding, reduced speech output, and comprehension deficits, often leading to aphasia. The study discussed the profound behavioral changes observed in FTD patients, including apathy, disinhibition, compulsive behaviors, and loss of empathy, the importance of an accurate and early diagnosis, and its challenges. We even reviewed the potential for targeted therapies and the essential role of multidisciplinary care in managing the language, speech, and behavioral aspects of FTD. By examining objective data and comprehensive research on the subject, this study offers valuable insights into FTD's profound effects on language, speech, and behavior, assisting in improved clinical management and potential therapeutic strategies for this devastating condition.

RESUMO. A demência frontotemporal (DFT) é uma doença neurodegenerativa progressiva definida pela deterioração seletiva dos lobos frontal e temporal do cérebro. Esta revisão abrangente explorou o efeito da DFT na linguagem, na fala e no comportamento. Os primeiros sintomas incluem dificuldade em encontrar palavras, redução da produção de fala e déficits de compreensão, muitas vezes levando à afasia. A revisão discutiu as profundas mudanças comportamentais observadas em pacientes com DFT, incluindo apatia, desinibição, comportamentos compulsivos e perda de empatia, a importância de um diagnóstico preciso e precoce e seus desafios. Também foi revisado o potencial para terapias direcionadas e o papel essencial do cuidado multidisciplinar no gerenciamento dos aspectos de linguagem, fala e comportamentais da DFT. Ao examinar os dados objetivos e a pesquisa abrangente sobre o assunto, esta revisão oferece insights valiosos sobre os efeitos profundos da DFT na linguagem, na fala e no comportamento, auxiliando no melhor manejo clínico e em possíveis estratégias terapêuticas para essa condição devastadora.

Frontotemporal-TDP and LATE Neurocognitive Disorders: A Pathophysiological and Genetic Approach.

Frontotemporal lobar degeneration (FTLD) belongs to a heterogeneous group of highly complex neurodegenerative diseases and represents the second cause of presenile dementia in individuals under 65. Frontotemporal-TDP is a subgroup of frontotemporal dementia characterized by the aggregation of abnormal protein deposits, predominantly transactive response DNA-binding protein 43 (TDP-43), in the frontal and temporal brain regions. These deposits lead to progressive degeneration of neurons resulting in cognitive and behavioral impairments. Limbic age-related encephalopathy (LATE) pertains to age-related cognitive decline primarily affecting the limbic system, which is crucial for memory, emotions, and learning. However, distinct, emerging research suggests a potential overlap in pathogenic processes, with some cases of limbic encephalopathy displaying TDP-43 pathology. Genetic factors play a pivotal role in both disorders. Mutations in various genes, such as progranulin (GRN) and chromosome 9 open reading frame 72 (C9orf72), have been identified as causative in frontotemporal-TDP. Similarly, specific genetic variants have been associated with an increased risk of developing LATE. Understanding these genetic links provides crucial insights into disease mechanisms and the potential for targeted therapies.

Diagnóstico de la variante conductual de demencia frontotemporal basado en estadios clínicos adaptado para países con baja educación: el caso de Perú

Demencia frontotemporal (DFT) es una condición neurodegenerativa escasamente reconocida en personas menores a 65 años de edad. El diagnóstico de DFT variante conductual (DFTvc) se basa en una entrevista clínica comprehensiva, complementada por una evaluación multidimensional (neurológica, cognitiva, neuropsiquiátrica, de biomarcadores e imágenes cerebrales) adaptada y validada a la población a estudiar; sin embargo, a pesar del incremento de su prevalencia en Latinoamérica y el Caribe, existe necesidad de herramientas estandarizadas y un consenso para el diagnóstico de DFTvc. El artículo intenta realizar una aproximación del enfoque de diagnóstico de DFTvc en escenario de paises con bajos y medianos ingresos, como el Perú.

Frontotemporal dementia (FTD) is a widely recognized neurodegenerative condition in people under 65 years old. The diagnosis of behavioral variant FTD (bvFTD) is based on a comprehensive clinical assessment, complemented by a multidimensional assessment (neurological, cognitive, neuropsychiatric, biomarker and brain imaging) adapted and validated to the population to be studied; however, despite its increasing prevalence in Latin America and the Caribbean, there is a need for standardized tools and consensus for the bvFTD diagnosis. The manuscript attempts to approximate the approach for the diagnosis of bvFTD in the setting of low and middle-income countries, including Peru.

Predicting Dementia Due to Alzheimer's Disease and Behavioral Variant Frontotemporal Dementia Using Algorithms with the Addenbrooke's Cognitive Examination-Revised Subscores Combined with Sociodemographic Factors.

BACKGROUND: Alzheimer's disease (AD) and behavioral variant frontotemporal dementia (bvFTD) are important causes of dementia with challenging differential diagnoses in many cases. Addenbrooke's Cognitive Examination-Revised (ACE-R) is a cognitive battery that may be useful to differentiate the two disorders. OBJECTIVE: The objectibe of this study is to investigate the value of the ACE-R combined with sociodemographic factors in the differential diagnosis between AD and bvFTD. METHODS: The ACE-R was administered to 102 patients with mild dementia due to probable AD, 37 with mild bvFTD, and 135 controls. Performances of patients and controls were analyzed by logistic regression and by ROC curves to refine the diagnostic accuracy of the ACE-R in AD and bvFTD. RESULTS: The ACE-R subscores Attention and Orientation, Fluency, and Memory, in combination with schooling differentiated AD from controls with an area under the ROC curve (AUC) of 0.936 (86% sensitivity and 87% specificity). The ACE-R subscores Attention and Orientation, Fluency, and Language, in combination with sex (male), age, and schooling, discriminated bvFTD from controls with an AUC of 0.908 (81% sensitivity and 95% specificity). In the differentiation between AD and bvFTD, the ACE-R subscores Attention and Orientation, Fluency, and Language, together with age, displayed an AUC of 0.865 (78% sensitivity and 85% specificity). CONCLUSION: The combination of ACE-R scores with sociodemographic data allowed good differentiation between AD and bvFTD in the study sample.

Diagnostic criteria in dementing illness. What's new? / Criterios diagnósticos en la enfermedad demencial ¿Qué hay de nuevo?

The spectrum of neurodegenerative diseases that primarily affect cognition and behaviorspreads from asymptomatic preclinical disease to very mild cognitive impairment to frank dementia. Alzheimer's disease (AD) is the most common cause of a decline in cognitive ability. Also, it is a devastating condition that affects patients and their entirefamilies of caregivers, exacting tremendous financial hardships. Diagnosis may be complicated by other forms of dementia that have symptoms and pathologies similar to AD. Knowing the key features and pathology of each type of dementia can help in the accurate diagnosis of patients, so they will receive the treatment and support services appropriate for their condition and maintain the highest possible functioning in daily life and quality of life. Differentiate, based on clinical criteria, neuropathology, and biomarkers, AD and its atypical variants from other common dementias including Dementia with Lewy Bodies, Vascular Cognitive Impairment, Frontotemporal Degeneration, and less frequent cognitive disorders. The importance of getting an accurate and early diagnosis of dementiais now increasingly significant to make important decisions about treatment, support, and care. Nonpharmacological as well as pharmacological interventions should be initiated once the diagnosis is obtained. Biochemical markers to identify Alzheimer's disease play a central role in the new diagnostic criteria for the disease and in the recent biological definition of AD. This review article presents up-to-date data regarding the recent diagnostic criteria of Alzheimer´s disease and related disorders, emphasizing its usefulness in routine clinical practice.

El espectro de enfermedades neurodegenerativas que afectan principalmente a la cognición y el comportamiento abarca desde la enfermedad preclínica asintomática hasta el deterioro cognitivo muy leve y la demencia franca. La enfermedad de Alzheimer (EA) es la causa más común de deterioro de la capacidad cognitiva. Es una enfermedad devastadora que afecta a los pacientes y a toda su familia de cuidadores, lo que supone enormes dificultades socioeconómicas y psicoemocionales. El diagnóstico puede complicarse debido a otras formas de demencia que presentan síntomas y patologías similares a la EA. Los marcadores bioquímicos para identificar la enfermedad de Alzheimer desempeñan un papel central en los nuevos criterios diagnósticos de la enfermedad y en la reciente definición biológica de la EA. Conocer las características claves y la patología de cada tipo de demencia puede ayudar en el diagnóstico preciso de los pacientes, a fin de que reciban el tratamiento y los servicios de apoyo adecuados a su condición y mantengan el mayor funcionamiento posible en la vida diaria y la calidad de vida. Por lo tanto es prioritario diferenciar, basándose en criterios clínicos, neuropatología y biomarcadores, la EA y sus variantes atípicas de otras demencias comunes como el Deterioro Cognitivo Vascular, la Degeneración Fronto- temporal entre otras, y los trastornos cognitivos menos frecuentes. Este artículo de revisión presenta datos actualizados relativos a los recientes criterios diagnósticos de algunas formas de demencia haciendo hincapié en su utilidad en la práctica clínica habitual. Se exponen los criterios de EA, de Demencia Vascular (DV), de la demencia Fronto-temporal (DFT) y de una forma rara de demencia, descripta en los últimos años, que se evidencia en pacientes muy añosos con un perfil similar a la EA. Se trata de la encefalopatía predominantemente límbica por tdp- 43 relacionada a la edad (LATE).

TANK-Binding Kinase 1 Mutation as a Rare Cause of Frontotemporal Dementia in a Mexican Patient: The First Case Report in a Tertiary Referral Hospital in Mexico.

Frontotemporal dementia (FTD) is a heterogeneous condition characterized by changes in behavior, personality, and language resulting from degeneration of the frontal and/or temporal lobes. A wide spectrum of clinical syndromes and an overlap with different motor disorders make this entity challenging for clinicians, both in achieving a correct diagnosis and providing proper treatment. Despite the majority of cases being sporadic, FTD has a hereditary component, and more than 10 disease-causing genes have been identified. We present the case of a Mexican patient with a positive family history of neurocognitive disorders who developed early-onset behavioral symptoms, cognitive alterations, and motor disturbances. After a comprehensive study and multiple assessments by various medical services, a molecular diagnosis was achieved by documenting a loss-of-function mutation in the TANK-binding kinase 1 (TBK1) gene, an extremely rare cause of FTD. Genetic diagnosis is crucial in these situations, as this mutation has been associated with rapid disease progression and the potential development of motor syndromes during its course. Our case underscores the challenges involved in reaching an accurate diagnosis, highlighting the importance of molecular testing. A thorough family history, past medical records, and a detailed description of symptom onset and progression are imperative, as they can significantly influence both treatment approaches and prognosis. Diagnostic errors, combined with their subsequent inappropriate treatment, can further deteriorate patients' quality of life.

Fear of Falling as a Behavioral Symptom in Neurocognitive Impaired Patients: Evidence from an Underrepresented Population.

BACKGROUND: Fear of falling (FoF) is a condition associated with falls, multi-morbidity, and functional impairment. To date it remains unknow which clinical, somatic, socio-demographic, behavioral, and emotional factors are associated with FoF and how these factors interact in people with Alzheimer's disease (AD) and behavioral variant frontotemporal dementia (bvFTD). OBJECTIVE: Identify the association of FoF with clinical, socio-demographic, and neuropsychiatric factors in patients with AD and bvFTD. METHODS: We evaluated 98 participants, 58 with AD and 40 with bvFTD at mild or moderate stages and assess FoF using the Falls Efficacy Scale-International. Additionally, we analyzed cognitive, physical performance variables, functional impairment, and affective and behavioral symptoms associated with FoF using standardized scales and a regression model analysis. RESULTS: The prevalence of FoF in AD and bvFTD was 51% and 40%, respectively. In the AD group, physical performance [F (3, 53) = 4.318, p = 0.009], the behavioral symptoms model [F (19, 38) = 3.314, p = 0.001], and the anxiety model [F (1, 56) = 13.4, p≤0.01] showed statistically significant values. In addition, the presence of hallucinations assessed with the Neuropsychiatric Inventory and social behavior assessed with the Mild Behavioral Impairment Checklist were significant. In contrast, in the bvFTD group, a homologous group of models was evaluated but we did not find any significant results. CONCLUSION: FoF in people with AD was related to physical performance, neuropsychiatric symptoms such as apathy and hallucinations, and affective symptoms such as anxiety. However, this pattern was not seen in the bvFTD group, and therefore further studies are required.

Current clinical and research practices on frontotemporal dementia in Brazil: a national survey / Práticas clínicas e cenário de pesquisa em demência frontotemporal no Brasil: uma enquete nacional

Abstract Background Frontotemporal dementia (FTD) is a frequent cause of young-onset dementia and represents a major challenge for the diagnosis and clinical management. It is essential to evaluate the difficulties faced by physicians on the diagnostic workup and on patient care. Objective The aim of this study was to investigate the current practices and the local limits on the diagnosis and management of FTD in Brazil. Methods We elaborated an online survey, composed of 29 questions and divided in four parts, comprising questions about existing health facilities, clinical practices related to FTD, and suggestions to increment the national research on FTD. The invitation to participate was sent by email to all neurologists affiliated to the Brazilian Academy of Neurology (n = 3658), and to all physicians who attended the XII Meeting of Researchers on Alzheimer's disease, in 2019 (n = 187). The invitation was also diffused through social media. Results 256 Brazilian physicians answered the questionnaire. The three most relevant disorders for the differential diagnosis of FTD were Alzheimer's disease (AD) (n = 211), bipolar disorder (n = 117) and dementia with Lewy bodies (n = 92). Most respondents (125/256) reported the difficulty in performing genetic testing as the main limit in the diagnostic of FTD. 93% and 63% of participants considered that the assessment of social cognition and AD CSF biomarkers are useful for the diagnosis of FTD, respectively. Conclusions The present study may provide valuable insights for the medical education and clinical training of physicians, and to foster future research on FTD in Brazil.

Resumo Antecedentes A demência frontotemporal (DFT) é causa frequente de demência pré-senil e representa um desafio em termos de diagnóstico e de manejo clínico. É essencial avaliar as dificuldades existentes na propedêutica e nos cuidados médicos. Objetivo Investigar as práticas médicas e as dificuldades para diagnóstico e manejo da DFT no Brasil. Métodos Elaborou-se um questionário online, composto de 29 questões, divididas em quatro partes, com perguntas sobre infraestrutura existente, práticas clínicas relacionadas à DFT e sugestões para desenvolver a pesquisa nacional na área. O convite para participação foi enviado por e-mail a todos neurologistas afiliados à Academia Brasileira de Neurologia (n = 3658), e aos médicos que participaram da XII Reunião de Pesquisadores de Doença de Alzheimer, em 2019 (n = 187). O convite também foi divulgado através de mídias sociais. Resultados 256 médicos brasileiros responderam o questionário. Os três principais diagnósticos diferenciais de DFT foram doença de Alzheimer (n = 211), transtorno bipolar (n = 117) e demência com corpos de Lewy (n = 92). A maior parte dos respondedores (125/256) apontou a dificuldade em realizar testagem genética como o maior limite no diagnóstico de DFT. 93% e 63% dos respondedores indicaram que a avaliação de cognição social e o uso de biomarcadores liquóricos de doença de Alzheimer são úteis no diagnóstico de DFT, respectivamente. Conclusões Estes resultados devem ser considerados na educação e treinamento médicos, e no desenvolvimento da pesquisa brasileira em DFT.

Social and non-social working memory in neurodegeneration.

Although social functioning relies on working memory, whether a social-specific mechanism exists remains unclear. This undermines the characterization of neurodegenerative conditions with both working memory and social deficits. We assessed working memory domain-specificity across behavioral, electrophysiological, and neuroimaging dimensions in 245 participants. A novel working memory task involving social and non-social stimuli with three load levels was assessed across controls and different neurodegenerative conditions with recognized impairments in: working memory and social cognition (behavioral-variant frontotemporal dementia); general cognition (Alzheimer's disease); and unspecific patterns (Parkinson's disease). We also examined resting-state theta oscillations and functional connectivity correlates of working memory domain-specificity. Results in controls and all groups together evidenced increased working memory demands for social stimuli associated with frontocinguloparietal theta oscillations and salience network connectivity. Canonical frontal theta oscillations and executive-default mode network anticorrelation indexed non-social stimuli. Behavioral-variant frontotemporal dementia presented generalized working memory deficits related to posterior theta oscillations, with social stimuli linked to salience network connectivity. In Alzheimer's disease, generalized working memory impairments were related to temporoparietal theta oscillations, with non-social stimuli linked to the executive network. Parkinson's disease showed spared working memory performance and canonical brain correlates. Findings support a social-specific working memory and related disease-selective pathophysiological mechanisms.