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Publication
Squamous Cell CarcinomaDeveloped in a TrichilemmalCyst, an Incidental Finding
(2023) Perez-Wilson, Jaime; Coulon, Gabriela; Whittle, Carolina; Castro-Avila, Ana Cristina
A 61-year-old man with no previous cancer history attended the dermatology clinic with a three-year history of asymptomatic swelling on the posterior aspect of the left elbow. Physical examination revealed a subcutaneous nodule of 1cm in diameter, with no epidermal changes. A Doppler ultrasound was requested, which revealed a predominantly dermal hypodermal cystic lesion with hypoechogenic content, an echogenic rim and small echogenic foci compatible with an epidermal cyst, no solid inner nodule was depicted (Fig. 1). An excisional biopsy was performed, which revealed a trichilemmal-type follicular cyst with a 0.5mm thickness well-differentiated squamous cell carcinoma (SCC) in its wall (Fig. 2). It was presented to the oncology committee that suggested local extent of 1cm The new biopsy did not show signs of residual neoplasia. At six months of follow-up, the patient did not present clinical or dermoscopic signs of recurrence.
Publication
Administration of Secretome Derived from Human Mesenchymal Stem Cells Induces Hepatoprotective Effects in Models of Idiosyncratic Drug-Induced Liver Injury Caused by Amiodarone or Tamoxifen
(2023) Huang, Ya-Lin; De Gregorio, Cristian; Silva, Verónica; Elorza, Álvaro; Léniz, Patricio; Aliaga, Víctor; Maracaja, Vinicius; Budini, Mauricio; Ezquer, Fernando; Ezquer, Marcelo
Drug-induced liver injury (DILI) is one of the leading causes of acute liver injury. While many factors may contribute to the susceptibility to DILI, obese patients with hepatic steatosis are particularly prone to suffer DILI. The secretome derived from mesenchymal stem cell has been shown to have hepatoprotective effects in diverse in vitro and in vivo models. In this study, we evaluate whether MSC secretome could improve DILI mediated by amiodarone (AMI) or tamoxifen (TMX). Hepatic HepG2 and HepaRG cells were incubated with AMI or TMX, alone or with the secretome of MSCs obtained from human adipose tissue. These studies demonstrate that coincubation of AMI or TMX with MSC secretome increases cell viability, prevents the activation of apoptosis pathways, and stimulates the expression of priming phase genes, leading to higher proliferation rates. As proof of concept, in a C57BL/6 mouse model of hepatic steatosis and chronic exposure to AMI, the MSC secretome was administered endovenously. In this study, liver injury was significantly attenuated, with a decrease in cell infiltration and stimulation of the regenerative response. The present results indicate that MSC secretome administration has the potential to be an adjunctive cell-free therapy to prevent liver failure derived from DILI caused by TMX or AMI.
Publication
A Third Dose of SARS-CoV-2 mRNA Vaccine Improves Immune Response in Chronic Kidney Disease Patients
(2023) Poli Harlowe, María Cecilia; Vial Cox, María Cecilia; Rey, Emma; González, Natalia; Cortés, Lina; Hormazabal, Juan; Ramírez, Carolina; De la Cruz, Javiera; Ulloa, Camilo
Chronic kidney disease (CKD) patients have an increased risk of morbidity and mortality following SARS-CoV-2 infection. Vaccination in these patients is prioritized, and monitoring of the immune response is paramount to define further vaccination strategies. This prospective study included a cohort of 100 adult CKD patients: 48 with kidney transplant (KT) and 52 on hemodialysis without prior COVID-19. The patients were assessed for humoral and cellular immune responses after four months of an anti-SARS-CoV-2 primary two-dose vaccination scheme (CoronaVac or BNT162b2) and one month after a booster third dose of BNT162b2 vaccine. We identified poor cellular and humoral immune responses in the CKD patients after a primary vaccination scheme, and these responses were improved by a booster. Robust polyfunctional CD4+ T cell responses were observed in the KT patients after a booster, and this could be attributed to a higher proportion of the patients having been vaccinated with homologous BNT162b2 schemes. However, even after the booster, the KT patients exhibited lower neutralizing antibodies, attributable to specific immunosuppressive treatments. Four patients suffered severe COVID-19 despite three-dose vaccination, and all had low polyfunctional T-cell responses, underscoring the importance of this functional subset in viral protection. In conclusion, a booster dose of SARS-CoV-2 mRNA vaccine in CKD patients improves the impaired humoral and cellular immune responses observed after a primary vaccination scheme.
Publication
A Novel Gemcitabine-Resistant Gallbladder Cancer Model Provides Insights into Molecular Changes Occurring during Acquired Resistance
(2023) Vergara, Luis; Bizama, Carolina; Zhong, Jun; Buchegger, Kurt; Suárez, Felipe; Rosa, Lorena; Ili, Carmen; Weber, Helga; Obreque, Javiera; Espinoza, Karena; Repetto, Gabriela; Roa, Juan; Leal, Pamela; García, Patricia
Treatment options for advanced gallbladder cancer (GBC) are scarce and usually rely on cytotoxic chemotherapy, but the effectiveness of any regimen is limited and recurrence rates are high. Here, we investigated the molecular mechanisms of acquired resistance in GBC through the development and characterization of two gemcitabine-resistant GBC cell sublines (NOZ GemR and TGBC1 GemR). Morphological changes, cross-resistance, and migratory/invasive capabilities were evaluated. Then, microarray-based transcriptome profiling and quantitative SILAC-based phosphotyrosine proteomic analyses were performed to identify biological processes and signaling pathways dysregulated in gemcitabine-resistant GBC cells. The transcriptome profiling of parental and gemcitabine-resistant cells revealed the dysregulation of protein-coding genes that promote the enrichment of biological processes such as epithelial-to-mesenchymal transition and drug metabolism. On the other hand, the phosphoproteomics analysis of NOZ GemR identified aberrantly dysregulated signaling pathways in resistant cells as well as active kinases, such as ABL1, PDGFRA, and LYN, which could be novel therapeutic targets in GBC. Accordingly, NOZ GemR showed increased sensitivity toward the multikinase inhibitor dasatinib compared to parental cells. Our study describes transcriptome changes and altered signaling pathways occurring in gemcitabine-resistant GBC cells, which greatly expands our understanding of the underlying mechanisms of acquired drug resistance in GBC.
Publication
Reliability and acceptability of web-based administration of Spanish ages and stages questionnaires third edition
(2023) Schonhaut , Luisa; Armijo, Ivan; Rojas, Paula; Cabrera, Leonardo; Boisier, Roberto
To analyse the reliability of 6 age intervals of Spanishweb-based Ages and Stages Questionnaires Third Edition(WB-ASQ-3) and parents' acceptability, in a clinical practicecontext, during COVID-19 pandemic and lockdown in Chile.Cross-sectional study with a longitudinal component. Inter-nal consistency was analysed by Cronbach's alpha and Pear-son product–moment correlation, Pearson's correlationsbetween intervals questionnaires were analysed. Accept-ability was determined using a parental satisfaction survey.1061 children completed 2318 validated questionnaires.Scores were compared with normative sample, except forGross motor at 8 and 12 months, and Communication at12, 18 and 24 months, without differences to the previousChileans sample. In domain analysis, Cronbach's alpharanged from 0.36 to 0.80 and reached 0.74 to 0.81 for theoverall test. Strong positive correlation between the domainand overall score was obtained. Correlation between mostquestionnaires at different ages was positive and significant.Parental surveys show high satisfaction; parents werethankful for being able to monitor children's development.WB-ASQ-3 is a reliable and feasible screening system, par-ticularly when the test is taken as a whole, rather than by domains. It is remarkably high acceptability among parents,especially in complex times such as the lockdown and theCOVID-19 pandemic.
Publication
Whole-genome sequencing reveals changes in genomic diversity and distinctive repertoires of T3SS and T6SS effector candidates in Chilean clinical Campylobacter strains
(2023) Katz, Assaf; Porte, Lorena; Weitzel, Thomas; Varela, Carmen; Muñoz, Cristina; Ugalde, Juan; Grim, Christopher; González, Narjol; Blondel, Carlos; Bravo, Verónica
Campylobacter is the leading cause of bacterial gastroenteritis worldwide and an emerging and neglected pathogen in South America. This zoonotic pathogen colonizes the gastrointestinal tract of a wide range of mammals and birds, with poultry as the most important reservoir for human infections. Apart from its high morbidity rates, the emergence of resistant strains is of global concern. The aims of this work were to determine genetic diversity, presence of antimicrobial resistance determinants and virulence potential of Campylobacter spp. isolated from patients with acute gastrointestinal disease at 'Clinica Alemana', Santiago de Chile. The study considered the isolation of Campylobacter spp., from stool samples during a 20-month period (January 2020 to September 2021). We sequenced (NextSeq, Illumina) and performed an in-depth analysis of the genome sequences of 88 Campylobacter jejuni and 2 Campylobacter coli strains isolated from clinical samples in Chile. We identified a high genetic diversity among C. jejuni strains and the emergence of prevalent clonal complexes, which were not identified in our previous reports. While ~40% of strains harbored a mutation in the gyrA gene associated with fluoroquinolone resistance, no macrolide-resistance determinants were detected. Interestingly, gene clusters encoding virulence factors such as the T6SS or genes associated with long-term sequelae such as Guillain-Barré syndrome showed lineage-relatedness. In addition, our analysis revealed a high degree of variability regarding the presence of fT3SS and T6SS effector proteins in comparison to type strains 81-176, F38011, and NCTC 11168 and 488. Our study provides important insights into the molecular epidemiology of this emerging foodborne pathogen. In addition, the differences observed regarding the repertoire of fT3SS and T6SS effector proteins could have an impact on the pathogenic potential and transmissibility of these Latin American isolates, posing another challenge in characterizing the infection dynamics of this emergent and neglected bacterial pathogen.
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Análisis e intervención de las prácticas de co-enseñanza entre docentes y profesionales del programa de integración escolar
(Universidad del Desarrollo. Facultad de Psicología, 2023) Gallardo Vargas, Fabián; Contreras Hernández, Fernando
La inclusión educativa avanza a nivel institucional desde la creación de los Programas de Integración en 2009 mediante el decreto 170 y la promulgación del decreto 83 en 2015 que oficializa la obligación de los establecimientos educacionales de apuntar a un Diseño Universal de los aprendizajes. Es en el contexto antes mencionado que la co-enseñanza ha adquirido protagonismo en el quehacer educativo de los establecimiento del pais. No obstante, este protagonismo, no necesariamente se traduce en su implantación efectiva dentro del aula, quedando en muchas ocasiones en una declaración de intención y principios, con tal de cumplir con los escasos lineamientos emitidos a nivel central. Por lo anterior es que resulta fundamental fomentar en los equipos de aula espacios de reflexión, como el planteado en este documento, el cual mediante un proceso de diagnóstico buscaba atender a los principales obstáculos para la implantación efectiva de la co-enseñanza, entre los cuales fue posible establecer la falta de lineamientos específicos y capacitaciones orientadas al desarrollo de habilidades prácticas, que les permitieran operacionalizar y organizar el trabajo colaborativo con tal de generar dinámicas de co-enseñanza que impacten en el aula. Es así como los equipos de aula construyeron e identificaron mecanismos y metodológicas que les permitan optimizar sus tiempos, mediante una planificación conjunta, distribución de roles y asignación de responsabilidades, además de incorporar la sistematizas y reflexión posterior para una mejora continua.
Publication
Maintenance of chronicity signatures in fibroblasts isolated from recessive dystrophic epidermolysis bullosa chronic wound dressings under culture conditions
(2023) De Gregorio, Cristian; Catalán, Evelyng; Garrido, Gabriel; Morandé, Pilar; Castillo, Jimena; Muñoz, Catalina; Cofré, Glenda; Huang, Ya-Lin; Cuadra, Bárbara; Murgas, Paola; Calvo, Margarita; Altermatt, Fernando; Joao, María; Palisson, Francis; South, Andrew; Ezquer, Marcelo; Ezquer, Marcelo; Fuentes, Ignacia
Background: Recessive Dystrophic Epidermolysis Bullosa (RDEB) is a rare inherited skin disease caused by variants in the COL7A1 gene, coding for type VII collagen (C7), an important component of anchoring fibrils in the basement membrane of the epidermis. RDEB patients suffer from skin fragility starting with blister formation and evolving into chronic wounds, inflammation and skin fibrosis, with a high risk of developing aggressive skin carcinomas. Restricted therapeutic options are limited by the lack of in vitro models of defective wound healing in RDEB patients. Results: In order to explore a more efficient, non-invasive in vitro model for RDEB studies, we obtained patient fibroblasts derived from discarded dressings) and examined their phenotypic features compared with fibroblasts derived from non-injured skin of RDEB and healthy-donor skin biopsies. Our results demonstrate that fibroblasts derived from RDEB chronic wounds (RDEB-CW) displayed characteristics of senescent cells, increased myofibroblast differentiation, and augmented levels of TGF-β1 signaling components compared to fibroblasts derived from RDEB acute wounds and unaffected RDEB skin as well as skin from healthy-donors. Furthermore, RDEB-CW fibroblasts exhibited an increased pattern of inflammatory cytokine secretion (IL-1β and IL-6) when compared with RDEB and control fibroblasts. Interestingly, these aberrant patterns were found specifically in RDEB-CW fibroblasts independent of the culturing method, since fibroblasts obtained from dressing of acute wounds displayed a phenotype more similar to fibroblasts obtained from RDEB normal skin biopsies. Conclusions: Our results show that in vitro cultured RDEB-CW fibroblasts maintain distinctive cellular and molecular characteristics resembling the inflammatory and fibrotic microenvironment observed in RDEB patients’ chronic wounds. This work describes a novel, non-invasive and painless strategy to obtain human fibroblasts chronically subjected to an inflammatory and fibrotic environment, supporting their use as an accessible model for in vitro studies of RDEB wound healing pathogenesis. As such, this approach is well suited to testing new therapeutic strategies under controlled laboratory conditions.
Publication
Successful eradication rate of Helicobacter pylori with empirical antibiotic treatment in pediatric patients from a Tertiary Hospital
(2023) Darritchon Lama, Sofía; Díaz García, Diego; Toledo Complido, Marcela; Lucero, Yalda
Helicobacter pylori infection is a common condition that, in the long term, is associated with the development of peptic ulcer disease and eventually gastric cancer, which could be prevented with timely treatment. Optimally, eradication success should be greater than 90%, but the recommended empirical reatments do not achieve these rates in real-life conditions. Objective: To determine the success rate of first-line empirical eradication treatment against H. pylori in pediatric patients treated in a tertiary hospital. Patients and Method: Retrospective descriptive study in patients with H. pylori infection detected in gastric biopsies and who had received first-line antibiotic treatment during the period 2017-2021. A negative result of an antigen test in stools or new iopsies after ≥ 1 month after
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Promoción de estrategias de autorregulación para el aprendizaje en estudiantes de técnico en nivel superior de educación diferencial en un Centro de Formación Técnica
(Universidad del Desarrollo. Facultad de Psicología, 2023) Bravo Garrido, Melisa; Hojman Ancelovici, Viviana
Este proyecto de intervención tuvo por propósito promover estrategias de autorregulación para el aprendizaje en estudiantes de Técnico en Nivel Superior de Educación Diferencial en el contexto de un Centro de Formación Técnica, mediante talleres formativos dirigidos a la comunidad estudiantil. La metodología empleada para la elaboración del proyecto responde a un levantamiento de problemática inicial mediante un proceso de diagnóstico y una delimitación teórica, por medio de la realización de una revisión bibliográfica que se reporta como un marco referencial. El proceso de diagnóstico en primera instancia quería evaluar las capacidades de autorregular el aprendizaje en contextos de clases remotas virtuales, no obstante, este foco se moviliza a evaluar las capacidades de aprendizaje autorregulado de forma independiente a la modalidad de clase, a partir de lo cual se levantan las acciones de la intervención. Tras realizar el proceso de intervención se puede concluir un logro total de las acciones; sin embargo, no se logra evidenciar del mismo modo un logro de los objetivos de aprendizaje presupuestados en el taller formativo, dado que existió una limitante importante de asistencia en los talleres, contando con sólo el 25% de participantes inscritos. Como reflexiones finales de este informe, se da cuenta que la participación de los talleres también depende de habilidades de autorregulación de los estudiantes, por lo que, al tratarse de una asistencia voluntaria, un escenario posible era no contar con la adherencia esperada. De este modo se finaliza este reporte, señalando posibles medidas que pudieran garantizar mayor participación de estudiantes en situaciones similares que contribuyan a formar sus habilidades de aprendizaje autorregulado.
Publication
Infecciones por helmintos intestinales en Chile: Análisis retrospectivo en Santiago, años 2015-2019
(2023) Ahumada, María; Haecker, Felipe; Porte, Lorena; Weitzel, Thomas
Introducción: Existe escasa evidencia epidemiológica actual sobre helmintos intestinales en Chile. Objetivo: Describir la prevalencia de infecciones por helmintos intestinales en un centro de salud en Santiago, Chile. Métodos: Análisis retrospectivo de helmintos intestinales diagnosticados en muestras parasitológicas de rutina en el Laboratorio de Microbiología de Clínica Alemana de Santiago, entre los años 2015 y 2019. Las pruebas diagnósticas se seleccionaron según la solicitud médica. Los datos se obtuvieron de los sistemas informáticos del laboratorio y se analizaron de manera anonimizada. Resultados: Se detectaron 127 infecciones por helmintos en 11.809 muestras estudiadas (1,1%). Estas infecciones fueron: 78 (61,4%) Enterobius vermicularis, 25 (19,6%) Dibothriocephalus/Adenocephalus spp., 9 (7,1%) Taenia spp., 6 (4,7%) Pseudoterranova spp., 5 (3,9%) Strongyloides stercoralis y 4 (3,1%) Ascaris lumbricoides. Enterobius vermicularis predominó en niños y adolescentes; Dibothriocephalus/ Adenocephalus spp. predominó en adultos. Conclusión: El estudio proporciona información epidemiológica actual sobre la distribución de helmintos intestinales en muestras clínicas en Santiago, Chile. Enterobius vermicularis fue prevalente, seguido de helmintos transmitidos por alimentos mientras que los transmitidos por el suelo solo se detectaron ocasionalmente. El surgimiento de difilobotriasis y anisakidosis (pseudoterranoviasis), es relevante y posiblemente se relacione con cambios en las condiciones de vida y la cultura alimentaria en Chile. Background: Epidemiological information on the current prevalence of intestinal helminths in Chile is scarce. Aim: To describe the prevalence of different intestinal helminth infections in a healthcare center in Santiago, Chile. Methods: We performed a retrospective analysis of intestinal helminths diagnosed in routine parasitological samples in the microbiological laboratory of Clínica Alemana Santiago, Chile, between 2015 and 2019. Diagnostic tests were applied according to the sender's request. Data were obtained from laboratory information systems and analyzed in an anonymized manner. Results: Among 11,809 samples, 127 (1.1%) helminth infections were detected, of those, 78 (61.4%) were Enterobius vermicularis, 25 (19.6%) Dibothriocephalus/Adenocephalus spp., 9 (7.1%) Taenia spp., 6 (4.7%) Pseudoterranova spp., 5 (3.9%) Strongyloides stercoralis, and 4 (3.1%) Ascaris lumbricoides. Enterobius vermicularis was predominant among children and adolescents, while Dibothriocephalus/Adenocephalus spp. was the most frequent helminth in adults. Conclusion: The study provides updated epidemiological information on distribution of helminth infections in clinical samples in Santiago, Chile. After E. vermicularis, food-borne helminths were second most prevalent, while soiltransmitted helminths were very rarely detected. The emergence of diphyllobothriasis and anisakidosis (pseudoterranoviasis) is noteworthy and possibly related to changes in living conditions and food culture in Chile.
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Bienestar emocional en los docentes de Escuela Básica en la comuna de Talcahuano
(Universidad del Desarrollo. Facultad de Psicología, 2023) González Herrera, Rocío; Sánchez Oñate, Alejandro
El presente proceso de diseño, implementación y evaluación de intervención, se realizó en la Escuela básica Libertad E-492 de Talcahuano, con la cual se estableció una vinculación y convenio para poder generar un diagnóstico e intervenir, en relación a las necesidades más relevantes que tanto el psicólogo como el equipo directivo pudieron levantar, en los distintos estamentos estudiantes, familias o docentes. Tanto el equipo directivo como el supervisor en terreno consideraron necesario apoyar el bienestar de los docentes, quienes se vieron afectados en el retorno a la presencialidad luego de la pandemia por COVID-19, sufriendo un impacto importante en cuanto a su salud mental, con evidencias de desgaste emocional, que los llevo a presentar diversas licencias médicas y mucho estrés. Por lo anterior, se consultó a los docentes que decidieron participar, mediante la aplicación de tres cuestionarios (Perma Profiler, DASS-21 y Escala de Malestar Psicológico de Kessler), sobre el nivel de bienestar que estarían experimentando, encontrándose altos índices de estrés y ansiedad, que se trabajaron a través de una intervención planificada a distancia, mediante la creación de un grupo de WhatsApp. A través de esta, se enviaron actividades que incluyen audios, textos, infografías y vídeos, en los cuales se incentivó el conocer las bases de la salud emocional y física, reconocimiento de emociones, actividades de relajación y respiración, y la importancia del autocuidado. Si bien los participantes dieron acuso recibo de las actividades sugeridas, se evidenció una baja participación en el grupo, no existiendo un reporte significativo por parte de los participantes, por lo que se aplicó un cuestionario que sirvió de evidencia para conocer las razones de la baja participación, lo que fue atribuido al exceso de virtualidad y poco contacto directo, además de la época del año, ya que se realizó principalmente en el último periodo de clases del año. Al finalizar el proceso de intervención se realizó una segunda aplicación de los cuestionarios, observando que los indicadores de estrés y ansiedad no disminuyeron. Se considera importante señalar que la intervención tiene carácter de auto administrable, por lo que se espera que el material enviado al establecimiento pueda ser utilizado en otras instancias, para que se pueda favorecer el bienestar de todos y todas quienes trabajan en la Escuela básica Libertad, priorizando un espacio seguro y de confianza en diferentes épocas del año. A continuación, se presenta el proceso diagnóstico y de intervención realizado.
Publication
Nanoscopic Distal Biceps Repair With Cortical Button and Interference Screw
(2023) Reinares, Felipe; De la Maza, Francisca; De la Paz; Joaquin; Angulo, Manuela; Lecaros, Juan; Ruiz, Francisco
Distal biceps pathology can be addressed using different techniques, each with its advantages and disadvantages. The current trend is to move toward minimally invasive procedures based on feasibility and known clinical benefits. Endoscopy for distal biceps pathology is a safe procedure. Through the NanoScope, this procedure is even more effective and safer.
Publication
Visual-spatial processing impairment in the occipital-frontal connectivity network at early stages of Alzheimer's disease
(2023) Plaza, Iván; Brunetti, Enzo; Montefusco, Rodrigo; Madariaga, Samuel; Hafelin, Rodrigo; Madariaga, Samuel; Ponce, Daniela; Behrens, María; Maldonado, Pedro; Lima, Andrea
Introduction: Alzheimer's disease (AD) is the leading cause of dementia worldwide, but its pathophysiological phenomena are not fully elucidated. Many neurophysiological markers have been suggested to identify early cognitive impairments of AD. However, the diagnosis of this disease remains a challenge for specialists. In the present cross-sectional study, our objective was to evaluate the manifestations and mechanisms underlying visual-spatial deficits at the early stages of AD. Methods: We combined behavioral, electroencephalography (EEG), and eye movement recordings during the performance of a spatial navigation task (a virtual version of the Morris Water Maze adapted to humans). Participants (69-88 years old) with amnesic mild cognitive impairment-Clinical Dementia Rating scale (aMCI-CDR 0.5) were selected as probable early AD (eAD) by a neurologist specialized in dementia. All patients included in this study were evaluated at the CDR 0.5 stage but progressed to probable AD during clinical follow-up. An equal number of matching healthy controls (HCs) were evaluated while performing the navigation task. Data were collected at the Department of Neurology of the Clinical Hospital of the Universidad de Chile and the Department of Neuroscience of the Faculty of Universidad de Chile. Results: Participants with aMCI preceding AD (eAD) showed impaired spatial learning and their visual exploration differed from the control group. eAD group did not clearly prefer regions of interest that could guide solving the task, while controls did. The eAD group showed decreased visual occipital evoked potentials associated with eye fixations, recorded at occipital electrodes. They also showed an alteration of the spatial spread of activity to parietal and frontal regions at the end of the task. The control group presented marked occipital activity in the beta band (15-20 Hz) at early visual processing time. The eAD group showed a reduction in beta band functional connectivity in the prefrontal cortices reflecting poor planning of navigation strategies. Discussion: We found that EEG signals combined with visual-spatial navigation analysis, yielded early and specific features that may underlie the basis for understanding the loss of functional connectivity in AD. Still, our results are clinically promising for early diagnosis required to improve quality of life and decrease healthcare costs.