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1.
Stem Cell Res ; 69: 103076, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36963214

RESUMEN

Human induced pluripotent stem cell (hiPSC) line INEUi001-A was reprogrammed from peripheral blood mononuclear cells (PBMC) using the lentiviral-hSTEMCCA-loxP vector. PBMCs were obtained from a 75- year-old female ALS/FTD disease patient carrying a heterozygous deletion within the C9ORF72 hexanucleotide repeat region resulting in a GGGGCCG sequence (∼1.16 repeats). C9ORF72 genotype was maintained and stemness and pluripotency confirmed in INEUi001-A hiPSC line.


Asunto(s)
Esclerosis Amiotrófica Lateral , Demencia Frontotemporal , Células Madre Pluripotentes Inducidas , Femenino , Humanos , Anciano , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Demencia Frontotemporal/genética , Células Madre Pluripotentes Inducidas/metabolismo , Proteína C9orf72/genética , Leucocitos Mononucleares/metabolismo , Genotipo
2.
Genome Med ; 14(1): 27, 2022 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-35260199

RESUMEN

BACKGROUND: The Colombian population, as well as those in other Latin American regions, arose from a recent tri-continental admixture among Native Americans, Spanish invaders, and enslaved Africans, all of whom passed through a population bottleneck due to widespread infectious diseases that left small isolated local settlements. As a result, the current population reflects multiple founder effects derived from diverse ancestries. METHODS: We characterized the role of admixture and founder effects on the origination of the mutational landscape that led to neurodegenerative disorders under these historical circumstances. Genomes from 900 Colombian individuals with Alzheimer's disease (AD) [n = 376], frontotemporal lobar degeneration-motor neuron disease continuum (FTLD-MND) [n = 197], early-onset dementia not otherwise specified (EOD) [n = 73], and healthy participants [n = 254] were analyzed. We examined their global and local ancestry proportions and screened this cohort for deleterious variants in disease-causing and risk-conferring genes. RESULTS: We identified 21 pathogenic variants in AD-FTLD related genes, and PSEN1 harbored the majority (11 pathogenic variants). Variants were identified from all three continental ancestries. TREM2 heterozygous and homozygous variants were the most common among AD risk genes (102 carriers), a point of interest because the disease risk conferred by these variants differed according to ancestry. Several gene variants that have a known association with MND in European populations had FTLD phenotypes on a Native American haplotype. Consistent with founder effects, identity by descent among carriers of the same variant was frequent. CONCLUSIONS: Colombian demography with multiple mini-bottlenecks probably enhanced the detection of founder events and left a proportionally higher frequency of rare variants derived from the ancestral populations. These findings demonstrate the role of genomically defined ancestry in phenotypic disease expression, a phenotypic range of different rare mutations in the same gene, and further emphasize the importance of inclusiveness in genetic studies.


Asunto(s)
Enfermedad de Alzheimer , Degeneración Lobar Frontotemporal , Enfermedades Neurodegenerativas , Enfermedad de Alzheimer/genética , Colombia , Efecto Fundador , Degeneración Lobar Frontotemporal/genética , Humanos , Mutación , Enfermedades Neurodegenerativas/genética
4.
Stem Cell Res ; 53: 102325, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33839546

RESUMEN

Human induced pluripotent stem cells (hiPSC) line FLENIi001-A was reprogrammed from dermal fibroblasts using the lentiviral-hSTEMCCA-loxP vector. Fibroblasts were obtained from a skin biopsy of a 72-year-old Caucasian male familial Alzheimer's disease patient carrying the T119I mutation in the PSEN1 gene. PSEN1 genotype was maintained and stemness and pluripotency confirmed in the FLENIi001-A hiPSC line.


Asunto(s)
Enfermedad de Alzheimer , Células Madre Pluripotentes Inducidas , Anciano , Enfermedad de Alzheimer/genética , Diferenciación Celular , Fibroblastos , Humanos , Masculino , Presenilina-1/genética
5.
Neurobiol Aging ; 85: 155.e9-155.e12, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31153663

RESUMEN

Mutations in PSEN1 are the most common cause of early-onset Alzheimer's disease (AD). In this article, we present an Argentine family with autosomal dominant early- and late-onset AD. The proband and 6 family members were available for genetic testing and clinical and neuropsychological assessments. Cerebrospinal fluid biomarkers were analyzed in the proband and a cousin (mutation carrier), who also underwent positron emission tomography using F-18-2-fluoro-2-deoxy-D-glucose and Pittsburgh compound B. Exon sequencing of PSEN1, PSEN2, and APP revealed a novel heterozygous variant in PSEN1 (c.356C>T; p.T119I). Median age of onset in the family was 56 years. However, the proband's uncle showed initial symptoms at age 71. Although no DNA was available, he was an obligate carrier because his daughter (proband's cousin) carried the mutation. Both the proband and his cousin exhibited biomarker evidence (cerebrospinal fluid or imaging) of underlying Alzheimer's pathology. Overall, our results support that the PSEN1 p.T119I variant is likely pathogenic.


Asunto(s)
Enfermedad de Alzheimer/genética , Familia , Mutación , Presenilina-1/genética , Edad de Inicio , Anciano , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/diagnóstico por imagen , Argentina , Biomarcadores/líquido cefalorraquídeo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Presenilina-1/líquido cefalorraquídeo
6.
J Gerontol A Biol Sci Med Sci ; 74(4): 442-445, 2019 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-30107413

RESUMEN

Systematic evaluation of biomarkers in representative populations is needed to validate their clinical utility. In this work, we assessed the diagnostic performance of cerebrospinal fluid (CSF) neurofilament light chain (NfL) in a neurocognitive clinical setting. A total of 51 patients with different cognitive clinical syndromes and 11 cognitively normal individuals were evaluated in a memory clinic in Argentina. Clinical conditions included mild cognitive impairment (MCI, n = 12), dementia of Alzheimer's type (DAT, n = 14), behavioral variant frontotemporal dementia (bvFTD, n = 13), and primary progressive aphasia (logopenic [n = 6], semantic [n = 2], and nonfluent [n = 4]). We quantified CSF NfL and core Alzheimer's disease biomarkers using commercially available ELISA kits. Cortical thickness was analyzed on brain magnetic resonance imaging scans from 10 controls and 10 patients. CSF NfL was significantly increased in MCI, FTD, and DAT patients compared with controls (Kruskal-Wallis, p < .0001). Interestingly, receiver operating characteristic curve analysis showed the highest area under the curve (AUC) value when analyzing control versus bvFTD patients (AUC = 0.9441). Also, we observed a marginally significant correlation between NfL levels and left orbitofrontal cortex thickness in a small group of patients with FTD. Overall, our results further support CSF NfL as a promising biomarker in the diagnostic workup of bvFTD.


Asunto(s)
Enfermedad de Alzheimer/líquido cefalorraquídeo , Afasia Progresiva Primaria/líquido cefalorraquídeo , Disfunción Cognitiva/líquido cefalorraquídeo , Demencia Frontotemporal/líquido cefalorraquídeo , Filamentos Intermedios/metabolismo , Anciano , Biomarcadores/líquido cefalorraquídeo , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Curva ROC
7.
Rev. argent. microbiol ; 48(4): 267-273, dic. 2016. graf, tab
Artículo en Inglés | LILACS | ID: biblio-843173

RESUMEN

Macrophomina phaseolina is a polyphagous phytopathogen, causing stalk rot on many commercially important species. Damages caused by this pathogen in soybean and maize crops in Argentina during drought and hot weather have increased due its ability to survive as sclerotia in soil and crop debris under non-till practices. In this work, we explored the in vitro production of plant cell wall-degrading enzymes --#91;pectinases (polygalacturonase and polymethylgalacturonase); cellulases (endoglucanase); hemicellulases (endoxylanase) and the ligninolytic enzyme laccase--#93; by several Argentinean isolates of M. phaseolina, and assessed the pathogenicity of these isolates as a preliminary step to establish the role of these enzymes in M. phaseolina-maize interaction. The isolates were grown in liquid synthetic medium supplemented with glucose, pectin, carboxymethylcellulose or xylan as carbon sources and/or enzyme inducers and glutamic acid as nitrogen source. Pectinases were the first cell wall-degrading enzymes detected and the activities obtained (polygalacturonase activity was between 0.4 and 1.3 U/ml and polymethylgalacturonase between 0.15 and 1.3 U/ml) were higher than those of cellulases and xylanases, which appeared later and in a lesser magnitude. This sequence would promote initial tissue maceration followed by cell wall degradation. Laccase was detected in all the isolates evaluated (activity was between 36 U/l and 63 U/l). The aggressiveness of the isolates was tested in maize, sunflower and watermelon seeds, being high on all the plants assayed. This study reports for the first time the potential of different isolates of M. phaseolina to produce plant cell wall-degrading enzymes in submerged fermentation.


Macrophomina phaseolina es un fitopatógeno polífago, causante de podredumbre carbonosa. Los daños que genera en cultivos de soja y maíz bajo siembra directa en Argentina, en períodos secos y calurosos, se incrementaron por su habilidad para sobrevivir como esclerocios en suelos y restos de cosecha. El propósito del trabajo fue estudiar la producción in vitro de enzimas degradadoras de pared celular vegetal (pectinasas --#91;poligalacturonasa y polimetilgalacturonasa--#93;; celulasas --#91;endoglucanasa--#93;; hemicelulasas --#91;endoxilanasa--#93; y la enzima ligninolítica lacasa) de varios aislamientos argentinos de M. phaseolina y evaluar la patogenicidad de esos aislamientos, como paso preliminar para establecer el papel de estas enzimas en la interacción M. phaseolina-maíz. Se estudió la cinética de crecimiento del hongo y la de la producción de dichas enzimas en medios de cultivo líquidos sintéticos con ácido glutámico como fuente de nitrógeno y con pectina, carboximetilcelulosa (CMC) o xilano como fuentes de carbono. Las pectinasas fueron las primeras enzimas detectadas y los máximos títulos registrados (1,4 UE/ml --#91;poligalacturonasa--#93; y 1,2 UE/ml --#91;polimetilgalacturonasa--#93;, respectivamente) superaron a los de celulasas y xilanasas, que aparecieron más tardíamente y en menor magnitud. Esta secuencia promovería la maceración inicial del tejido, seguida luego por la degradación de la pared celular vegetal. Se detectó actividad lacasa en todos los aislamientos (36 a 63 U/l). La agresividad de todos los aislamientos resultó alta en los 3 hospedantes evaluados: semillas de maíz, de girasol y de melón. En este trabajo se investiga por primera vez el potencial de distintos aislamientos de M. phaseolina para producir enzimas degradadoras de pared celular vegetal en cultivo líquido.


Asunto(s)
Técnicas In Vitro/métodos , Pared Celular/enzimología , Zea mays/enzimología , Zea mays/parasitología , Poligalacturonasa/aislamiento & purificación , Celulasa/aislamiento & purificación , Endo-1,4-beta Xilanasas/aislamiento & purificación
8.
Rev Argent Microbiol ; 48(4): 267-273, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27825736

RESUMEN

Macrophomina phaseolina is a polyphagous phytopathogen, causing stalk rot on many commercially important species. Damages caused by this pathogen in soybean and maize crops in Argentina during drought and hot weather have increased due its ability to survive as sclerotia in soil and crop debris under non-till practices. In this work, we explored the in vitro production of plant cell wall-degrading enzymes [pectinases (polygalacturonase and polymethylgalacturonase); cellulases (endoglucanase); hemicellulases (endoxylanase) and the ligninolytic enzyme laccase] by several Argentinean isolates of M. phaseolina, and assessed the pathogenicity of these isolates as a preliminary step to establish the role of these enzymes in M. phaseolina-maize interaction. The isolates were grown in liquid synthetic medium supplemented with glucose, pectin, carboxymethylcellulose or xylan as carbon sources and/or enzyme inducers and glutamic acid as nitrogen source. Pectinases were the first cell wall-degrading enzymes detected and the activities obtained (polygalacturonase activity was between 0.4 and 1.3U/ml and polymethylgalacturonase between 0.15 and 1.3U/ml) were higher than those of cellulases and xylanases, which appeared later and in a lesser magnitude. This sequence would promote initial tissue maceration followed by cell wall degradation. Laccase was detected in all the isolates evaluated (activity was between 36U/l and 63U/l). The aggressiveness of the isolates was tested in maize, sunflower and watermelon seeds, being high on all the plants assayed. This study reports for the first time the potential of different isolates of M. phaseolina to produce plant cell wall-degrading enzymes in submerged fermentation.


Asunto(s)
Ascomicetos/enzimología , Proteínas Fúngicas/metabolismo , Argentina , Ascomicetos/crecimiento & desarrollo , Ascomicetos/aislamiento & purificación , Ascomicetos/patogenicidad , Carbono/metabolismo , Pared Celular/metabolismo , Celulasa/aislamiento & purificación , Celulasa/metabolismo , Citrullus/microbiología , Medios de Cultivo , Endo-1,4-beta Xilanasas/aislamiento & purificación , Endo-1,4-beta Xilanasas/metabolismo , Fermentación , Proteínas Fúngicas/aislamiento & purificación , Glicósido Hidrolasas/aislamiento & purificación , Glicósido Hidrolasas/metabolismo , Helianthus/microbiología , Microbiología Industrial/métodos , Lacasa/aislamiento & purificación , Lacasa/metabolismo , Nitrógeno/metabolismo , Poligalacturonasa/aislamiento & purificación , Poligalacturonasa/metabolismo , Semillas/microbiología , Zea mays/microbiología
9.
Neurobiol Aging ; 40: 192.e13-192.e15, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26925510

RESUMEN

Pathologic expansion of the G4C2 repeat in C9orf72 is the main genetic cause of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). To evaluate the frequency of the G4C2 expansion in a Latin American cohort of FTD and ALS patients, we used a 2-step genotyping strategy. For FTD, we observed an overall expansion frequency of 18.2% (6 of 33 unrelated cases). Moreover, the C9orf72 expansion accounted for 37.5% of all familial FTD cases (6 of 16 families). The expansion frequency in sporadic ALS cases was 2% (1 of 47 unrelated patients), whereas we observed the expansion in 1 of 3 families with a positive history for ALS. Overall, the expansion frequency in our FTD group was similar to that reported for patients in Europe and North America, whereas the frequency in our sporadic ALS group was significantly lower. To our knowledge, this is the first report on the frequency of the C9orf72 expansion in a Latin American population.


Asunto(s)
Esclerosis Amiotrófica Lateral/genética , Expansión de las Repeticiones de ADN/genética , Demencia Frontotemporal/genética , Proteínas/genética , Adulto , Anciano , Anciano de 80 o más Años , Argentina , Proteína C9orf72 , Femenino , Técnicas de Genotipaje/métodos , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos , Adulto Joven
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