1,161 research outputs found

    Directing neuronal cell fate in vitro: achievements and challenges

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    Human pluripotent stem cell (PSC) technology and direct somatic cell reprogramming have opened up a promising new avenue in the field of neuroscience. These recent advances allow researchers to obtain virtually any cell type found in the human brain, making it possible to produce and study functional neurons in laboratory conditions for both scientific and medical purposes. Although distinct approaches have shown to be successful in directing neuronal cell fate in vitro, their refinement and optimization, as well as the search for alternative approaches, remains necessary to help realize the full potential of the eventually derived neuronal populations. Furthermore, we are currently limited in the number of neuronal subtypes whose induction is fully established, and different cultivation protocols for each subtype exist, making it challenging to increase the reproducibility and decrease the variances that are observed between different protocols. In this review, we summarize the progress that has been made in generating various neuronal subtypes from PSCs and somatic cells, with special emphasis on chemically defined systems, transcription factor-mediated reprogramming and epigenetic-based approaches. We also discuss the efforts that are being made to increase the efficiency of current protocols and address the potential for the use of these cells in disease modelling, drug discovery and regenerative medicine

    Increased 5-hydroxymethylation levels in the sub ventricular zone of the Alzheimer's brain

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    © 2016 The Authors. The subventricular zone (SVZ) is a site of neurogenesis in the aging brain, and epigenetic mechanisms have been implicated in regulating the "normal" distribution of new nerve cells into the existing cellular milieu. In a case-control study of human primary SVZ cultures and fixed tissue from the same individuals, we have found significant increases in DNA hydroxymethylation levels in the SVZ of Alzheimer's disease patients compared with nondiseased control subjects. We show that this increase in hydroxymethylation directly correlates to an increase in cellular proliferation in Alzheimer's disease precursor cells, which implicates the hydroxymethylation tag to a higher degree of cellular proliferation

    M & L Jaargang 22/1

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    Jan Van Hove Een ambtenaar maakt het verschil.Daniël Ostyn Het Europees Monumentenjaar 1975. Een doorbraak in de monumentenzorg.Kamiel D\u27Hooghe Aan Edgard Goedleven: een hommage met grand-jeu.Paul Van den Bremt - Landschapszorg, de groene bril van Edgard Goedleven.Robert Piessens Edgard Goedleven, penningmeester van de Vereniging voor het bevorderen van het Belgisch trekpaard.Suzanne Van Aerschot-Van Haeverbeeck Inventarisatie van het bouwkundig erfgoed: een eindeloos verhaal.Mark Fierlafijn Van cultureel tot grondgebonden. Een beknopt overzicht van de evolutie van de decreet- en regelgeving inzake monumenten en landschappen.Suzanne Van Aerschot-Van Haeverbeeck Vlaams erfgoed Werelderfgoed. Een achterstand ingehaald.André Matthys Edgard Goedleven et la politique patrimoniale internationale.Marjan Buyle Een monument is meer dan een gevel alleen.Piet Jaspaert De financier en organisator.Marcel M. Celis De verbeelding aan de macht: M&L van 1 tot 127

    Оцінювання за зашумленними спостереженнями невідомих даних лінійних еліптичних рівнянь, що допускають змішане варіаційне формулювання

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    Получен новый класс систем вариационных уравнений через решения которых выражаются минимаксные оценки значений функционалов от неизвестных правых частей линейных эллиптических уравнений 2-го порядка.Одержаний новий клас систем варіаційних рівнянь через розв'язки яких виражаються мінімаксні оцінки значень функционалів від невідомих правих частин лінійних еліптичних рівнянь 2-го порядку.We obtain a new class of systems of variational equations via whose solutions the minimax estimates of values of functionals from unknown right-hand sides of the second order linear elliptic equations are expressed

    Seasonal changes in a sandy beach fish assemblage at Canto Grande, Santa Catarina, South Brazil

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    Copyright © 2004 Coastal Education and Research Foundation (CERF).Neste trabalho realizaramse amostragens, com uma rede de praia, de modo a estudar a comunidade de peixes de substrato arenoso na enseada de Canto Grande, Santa Catarina, Brasil. As amostragens realizaramse em intervalos de 3 horas durante períodos de 24 h, numa base bimensal, entre Abril de 1996 e Fevereiro de 1997. Verificouse existir uma variação sazonal no número de espécies, densidade de peixes e biomassa, tendo os valores mais elevados ocorrido em Fevereiro (38 espécies, 257.6 peixes 1000 mˉ², 2286.4 g 1000 mˉ²). Recolheuse um total de 67 espécies, pertencentes a 56 géneros e a 33 famílias, sendo a comunidade dominada por sete espécies pertencentes a três famílias: Atherinella brasiliensis (Atherinidae); Brevoortia pectinata, Harengula clupeola e Sardinella brasiliensis (Clupeidae); Anchoviella lepidontostole, Cetengraulis edentulus e Lycengraulis grossidens (Engraulidae). Tanto a diversidade de espécies (H′) como a equitabilidade (J′) foram médias a elevadas ao longo do ano devido à baixa dominância. A maior mudança na estrutura da comunidade ocorreu entre os meses de Inverno (Julho e Agosto) e as outras estações. Nenhuma das espécies dominantes pode ser classificada como residente. Os principais predadores foram Pomatomus saltator (Inverno) e Trichiurus lepturus (Verão). A maior parte das espécies observadas foram ou peixes juvenis ou espécies pelágicas de pequeno tamanho e fortemente gregárias.ABSTRACT: A shallow-water fish assemblage, over a soft, sandy bottom, at Canto Grande, Santa Catarina, Brazil, was sampled with a beach seine. Sampling was undertaken at 3 h intervals over 24 h on a bimonthly basis between April 1996 and February 1997. There was a seasonal variation in the number of species, density of fishes and biomass with the highest values in February (38 species, 257.6 fish 1000 mˉ², 2286.4 g 1000 mˉ²). A total of 67 species, belonging to 56 genera and 33 families were collected and the assemblage was dominated by seven species belonging to three families: Atherinella brasiliensis (Atherinidae); Brevoortia pectinata, Harengula clupeola and Sardinella brasiliensis (Clupeidae); Anchoviella lepidontostole, Cetengraulis edentulus and Lycengraulis grossidens (Engraulidae). Species diversity (H′) and equitability (J′) were medium to high throughout the year due to the low dominance. The largest change in the assemblage structure occurred between winter months (July and August) and the other seasons. None of the dominant species can be classified as a resident. Main predators were Pomatomus saltator (winter) and Trichiurus lepturus (summer). Most of the species observed were either juvenile fish or small pelagic and strongly gregarious species

    Systemic multipotent adult progenitor cells improve long-term neurodevelopmental outcomes after preterm hypoxic-ischemic encephalopathy

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    There is an urgent need for therapies that could reduce the disease burden of preterm hypoxic-ischemic encephalopathy. Here, we evaluate the long-term effects of multipotent adult progenitor cells (MAPC) on long-term behavioral outcomes in a preterm rat model of perinatal asphyxia. Rats of both sexes were treated with two doses of MAPCs within 24 h after the insult. Locomotor, cognitive and psychiatric impairments were evaluated starting at 1.5 (juvenile) and 6 months (adult). Hypoxia-ischemia affected locomotion, cognition, and anxiety in a sex-dependent manner, with higher vulnerability observed in males. The MAPC therapy partially attenuated deficits in object recognition memory in females of all tested ages, and in the adult males. The hypoxic insult caused delayed hyperactivity in adult males, which was corrected by MAPC therapy. These results suggest that MAPCs may have long-term benefits for neurodevelopmental outcome after preterm birth and global hypoxia-ischemia, which warrants further preclinical exploration

    Gene-Environment Interaction Research and Transgenic Mouse Models of Alzheimer's Disease

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    The etiology of the sporadic form of Alzheimer's disease (AD) remains largely unknown. Recent evidence has suggested that gene-environment interactions (GxE) may play a crucial role in its development and progression. Whereas various susceptibility loci have been identified, like the apolipoprotein E4 allele, these cannot fully explain the increasing prevalence of AD observed with aging. In addition to such genetic risk factors, various environmental factors have been proposed to alter the risk of developing AD as well as to affect the rate of cognitive decline in AD patients. Nevertheless, aside from the independent effects of genetic and environmental risk factors, their synergistic participation in increasing the risk of developing AD has been sparsely investigated, even though evidence points towards such a direction. Advances in the genetic manipulation of mice, modeling various aspects of the AD pathology, have provided an excellent tool to dissect the effects of genes, environment, and their interactions. In this paper we present several environmental factors implicated in the etiology of AD that have been tested in transgenic animal models of the disease. The focus lies on the concept of GxE and its importance in a multifactorial disease like AD. Additionally, possible mediating mechanisms and future challenges are discussed

    Molecular diagnostics of intestinal parasites in returning travellers

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    A new diagnostic strategy was assessed for the routine diagnosis of intestinal parasites in returning travellers and immigrants. Over a period of 13 months, unpreserved stool samples, patient characteristics and clinical data were collected from those attending a travel clinic. Stool samples were analysed on a daily basis by microscopic examination and antigen detection (i.e. care as usual), and compared with a weekly performed multiplex real-time polymerase chain reaction (PCR) analysis on Entamoeba histolytica, Giardia lamblia, Cryptosporidium and Strongyloides stercoralis. Microscopy and antigen assays of 2,591 stool samples showed E. histolytica, G. lamblia, Cryptosporidium and S. stercoralis in 0.3, 4.7, 0.5 and 0.1% of the cases, respectively. These detection rates were increased using real-time PCR to 0.5, 6.0, 1.3 and 0.8%, respectively. The prevalence of ten additional pathogenic parasite species identified with microscopy was, at most, 0.5%. A pre-selective decision tree based on travel history or gastro-intestinal complaints could not be made. With increased detection rates at a lower workload and the potential to extend with additional parasite targets combined with fully automated DNA isolation, molecular high-throughput screening could eventually replace microscopy to a large extent

    An epigenome-wide association study of Alzheimer's disease blood highlights robust DNA hypermethylation in the HOXB6 gene

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    This is the final version. Available from the publisher via the DOI in this record.A growing number of epigenome-wide association studies have demonstrated a role for DNA methylation in the brain in Alzheimer's disease. With the aim of exploring peripheral biomarker potential, we have examined DNA methylation patterns in whole blood collected from 284 individuals in the AddNeuroMed study, which included 89 nondemented controls, 86 patients with Alzheimer's disease, and 109 individuals with mild cognitive impairment, including 38 individuals who progressed to Alzheimer's disease within 1 year. We identified significant differentially methylated regions, including 12 adjacent hypermethylated probes in the HOXB6 gene in Alzheimer's disease, which we validated using pyrosequencing. Using weighted gene correlation network analysis, we identified comethylated modules of genes that were associated with key variables such as APOE genotype and diagnosis. In summary, this study represents the first large-scale epigenome-wide association study of Alzheimer's disease and mild cognitive impairment using blood. We highlight the differences in various loci and pathways in early disease, suggesting that these patterns relate to cognitive decline at an early stage.Alzheimer's Society, United KingdomMedical Research Council (MRC)NIH, United States, R01 grantAlzheimer's Research U
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