Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 86
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Proc Natl Acad Sci U S A ; 117(33): 20127-20138, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32747535

RESUMO

Medulloblastoma is the most common malignant brain tumor in children. Here we describe a medulloblastoma model using Induced pluripotent stem (iPS) cell-derived human neuroepithelial stem (NES) cells generated from a Gorlin syndrome patient carrying a germline mutation in the sonic hedgehog (SHH) receptor PTCH1. We found that Gorlin NES cells formed tumors in mouse cerebellum mimicking human medulloblastoma. Retransplantation of tumor-isolated NES (tNES) cells resulted in accelerated tumor formation, cells with reduced growth factor dependency, enhanced neurosphere formation in vitro, and increased sensitivity to Vismodegib. Using our model, we identified LGALS1 to be a GLI target gene that is up-regulated in both Gorlin tNES cells and SHH-subgroup of medulloblastoma patients. Taken together, we demonstrate that NES cells derived from Gorlin patients can be used as a resource to model medulloblastoma initiation and progression and to identify putative targets.


Assuntos
Proteínas Hedgehog/metabolismo , Meduloblastoma/genética , Células-Tronco Neurais/fisiologia , Anilidas/farmacologia , Animais , Síndrome do Nevo Basocelular/genética , Síndrome do Nevo Basocelular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Galectina 1/genética , Galectina 1/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas Hedgehog/genética , Humanos , Camundongos , Neoplasias Experimentais , Receptor Patched-1/genética , Piridinas/farmacologia
2.
Hum Mutat ; 43(11): 1567-1575, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35842787

RESUMO

Prader-Willi syndrome (PWS; MIM# 176270) is a neurodevelopmental disorder caused by the loss of expression of paternally imprinted genes within the PWS region located on 15q11.2. It is usually caused by either maternal uniparental disomy of chromosome 15 (UPD15) or 15q11.2 recurrent deletion(s). Here, we report a healthy carrier of a balanced X;15 translocation and her two daughters, both with the karyotype 45,X,der(X)t(X;15)(p22;q11.2),-15. Both daughters display symptoms consistent with haploinsufficiency of the SHOX gene and PWS. We explored the architecture of the derivative chromosomes and investigated effects on gene expression in patient-derived neural cells. First, a multiplex ligation-dependent probe amplification methylation assay was used to determine the methylation status of the PWS-region revealing maternal UPD15 in daughter 2, explaining her clinical symptoms. Next, short read whole genome sequencing and 10X genomics linked read sequencing was used to pinpoint the exact breakpoints of the translocation. Finally, we performed transcriptome sequencing on neuroepithelial stem cells from the mother and from daughter 1 and observed biallelic expression of genes in the PWS region (including SNRPN) in daughter 1. In summary, our multi-omics analysis highlights two different PWS mechanisms in one family and provide an example of how structural variation can affect imprinting through long-range interactions.


Assuntos
Metilação de DNA , Síndrome de Prader-Willi , Cromossomos Humanos Par 15/genética , Feminino , Impressão Genômica , Humanos , Síndrome de Prader-Willi/genética , Translocação Genética , Dissomia Uniparental/genética , Proteínas Centrais de snRNP/genética
3.
Environ Toxicol ; 37(8): 2044-2057, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35485992

RESUMO

Glyphosate-based herbicides (GBH) are among the most sold pesticides in the world. There are several formulations based on the active ingredient glyphosate (GLY) used along with other chemicals to improve the absorption and penetration in plants. The final composition of commercial GBH may modify GLY toxicological profile, potentially enhancing its neurotoxic properties. The developing nervous system is particularly susceptible to insults occurring during the early phases of development, and exposure to chemicals in this period may lead to persistent impairments on neurogenesis and differentiation. The aim of this study was to evaluate the long-lasting effects of a sub-cytotoxic concentration, 2.5 parts per million of GBH and GLY, on the differentiation of human neuroepithelial stem cells (NES) derived from induced pluripotent stem cells (iPSC). We treated NES cells with each compound and evaluated the effects on key cellular processes, such as proliferation and differentiation in daughter cells never directly exposed to the toxicants. We found that GBH induced a more immature neuronal profile associated to increased PAX6, NESTIN and DCX expression, and a shift in the differentiation process toward glial cell fate at the expense of mature neurons, as shown by an increase in the glial markers GFAP, GLT1, GLAST and a decrease in MAP2. Such alterations were associated to dysregulation of key genes critically involved in neurogenesis, including PAX6, HES1, HES5, and DDK1. Altogether, the data indicate that subtoxic concentrations of GBH, but not of GLY, induce long-lasting impairments on the differentiation potential of NES cells.


Assuntos
Herbicidas , Glicina/análogos & derivados , Glicina/toxicidade , Herbicidas/toxicidade , Humanos , Neurogênese , Neurônios , Glifosato
4.
Int J Mol Sci ; 23(16)2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-36012658

RESUMO

Balanced structural variants, such as reciprocal translocations, are sometimes hard to detect with sequencing, especially when the breakpoints are located in repetitive or insufficiently mapped regions of the genome. In such cases, long-range information is required to resolve the rearrangement, identify disrupted genes and, in symptomatic carriers, pinpoint the disease-causing mechanisms. Here, we report an individual with autism, epilepsy and osteoporosis and a de novo balanced reciprocal translocation: t(17;19) (p13;p11). The genomic DNA was analyzed by short-, linked- and long-read genome sequencing, as well as optical mapping. Transcriptional consequences were assessed by transcriptome sequencing of patient-specific neuroepithelial stem cells derived from induced pluripotent stem cells (iPSC). The translocation breakpoints were only detected by long-read sequencing, the first on 17p13, located between exon 1 and exon 2 of MINK1 (Misshapen-like kinase 1), and the second in the chromosome 19 centromere. Functional validation in induced neural cells showed that MINK1 expression was reduced by >50% in the patient's cells compared to healthy control cells. Furthermore, pathway analysis revealed an enrichment of changed neural pathways in the patient's cells. Altogether, our multi-omics experiments highlight MINK1 as a candidate monogenic disease gene and show the advantages of long-read genome sequencing in capturing centromeric translocations.


Assuntos
Transtorno Autístico , Epilepsia , Osteoporose , Proteínas Serina-Treonina Quinases , Transtorno Autístico/genética , Mapeamento Cromossômico , Epilepsia/genética , Humanos , Osteoporose/genética , Proteínas Serina-Treonina Quinases/genética , Translocação Genética
5.
J Neuroinflammation ; 18(1): 124, 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34082772

RESUMO

BACKGROUND: Alzheimer's disease (AD) and Parkinson's disease (PD) are characterized by brain accumulation of aggregated amyloid-beta (Aß) and alpha-synuclein (αSYN), respectively. In order to develop effective therapies, it is crucial to understand how the Aß/αSYN aggregates can be cleared. Compelling data indicate that neuroinflammatory cells, including astrocytes and microglia, play a central role in the pathogenesis of AD and PD. However, how the interplay between the two cell types affects their clearing capacity and consequently the disease progression remains unclear. METHODS: The aim of the present study was to investigate in which way glial crosstalk influences αSYN and Aß pathology, focusing on accumulation and degradation. For this purpose, human-induced pluripotent cell (hiPSC)-derived astrocytes and microglia were exposed to sonicated fibrils of αSYN or Aß and analyzed over time. The capacity of the two cell types to clear extracellular and intracellular protein aggregates when either cultured separately or in co-culture was studied using immunocytochemistry and ELISA. Moreover, the capacity of cells to interact with and process protein aggregates was tracked using time-lapse microscopy and a customized "close-culture" chamber, in which the apical surfaces of astrocyte and microglia monocultures were separated by a <1 mm space. RESULTS: Our data show that intracellular deposits of αSYN and Aß are significantly reduced in co-cultures of astrocytes and microglia, compared to monocultures of either cell type. Analysis of conditioned medium and imaging data from the "close-culture" chamber experiments indicate that astrocytes secrete a high proportion of their internalized protein aggregates, while microglia do not. Moreover, co-cultured astrocytes and microglia are in constant contact with each other via tunneling nanotubes and other membrane structures. Notably, our live cell imaging data demonstrate that microglia, when attached to the cell membrane of an astrocyte, can attract and clear intracellular protein deposits from the astrocyte. CONCLUSIONS: Taken together, our data demonstrate the importance of astrocyte and microglia interactions in Aß/αSYN clearance, highlighting the relevance of glial cellular crosstalk in the progression of AD- and PD-related brain pathology.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Astrócitos/metabolismo , Astrócitos/patologia , Microglia/metabolismo , Microglia/patologia , Agregados Proteicos , Agregação Patológica de Proteínas , alfa-Sinucleína/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Encéfalo/metabolismo , Estruturas da Membrana Celular/fisiologia , Células Cultivadas , Técnicas de Cocultura , Humanos , Células-Tronco Pluripotentes Induzidas , Microscopia Confocal , Nanotubos , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Proteólise
6.
Mol Cell Neurosci ; 107: 103533, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32717317

RESUMO

The blood-brain barrier (BBB) constitutes the interface between the blood and the brain tissue. Its primary function is to maintain the tightly controlled microenvironment of the brain. Models of the BBB are useful for studying the development and maintenance of the BBB as well as diseases affecting it. Furthermore, BBB models are important tools in drug development and support the evaluation of the brain-penetrating properties of novel drug molecules. Currently used in vitro models of the BBB include immortalized brain endothelial cell lines and primary brain endothelial cells of human and animal origin. Unfortunately, many cell lines and primary cells do not recreate physiological restriction of transport in vitro. Human-induced pluripotent stem cell (iPSC)-derived brain endothelial cells have proven a promising alternative source of brain endothelial-like cells that replicate tight cell layers with low paracellular permeability. Given the possibility to generate large amounts of human iPSC-derived brain endothelial cells they are a feasible alternative when modelling the BBB in vitro. iPSC-derived brain endothelial cells form tight cell layers in vitro and their barrier properties can be enhanced through coculture with other cell types of the BBB. Currently, many different models of the BBB using iPSC-derived cells are under evaluation to study BBB formation, maintenance, disruption, drug transport and diseases affecting the BBB. This review summarizes important functions of the BBB and current efforts to create iPSC-derived BBB models in both static and dynamic conditions. In addition, it highlights key model requirements and remaining challenges for human iPSC-derived BBB models in vitro.


Assuntos
Transporte Biológico/fisiologia , Barreira Hematoencefálica/metabolismo , Encéfalo/citologia , Células Endoteliais/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Animais , Barreira Hematoencefálica/patologia , Técnicas de Cocultura/métodos , Humanos
7.
EMBO J ; 35(18): 1963-78, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27354364

RESUMO

Pre-B-cell leukemia homeobox (PBX) transcription factors are known to regulate organogenesis, but their molecular targets and function in midbrain dopaminergic neurons (mDAn) as well as their role in neurodegenerative diseases are unknown. Here, we show that PBX1 controls a novel transcriptional network required for mDAn specification and survival, which is sufficient to generate mDAn from human stem cells. Mechanistically, PBX1 plays a dual role in transcription by directly repressing or activating genes, such as Onecut2 to inhibit lateral fates during embryogenesis, Pitx3 to promote mDAn development, and Nfe2l1 to protect from oxidative stress. Notably, PBX1 and NFE2L1 levels are severely reduced in dopaminergic neurons of the substantia nigra of Parkinson's disease (PD) patients and decreased NFE2L1 levels increases damage by oxidative stress in human midbrain cells. Thus, our results reveal novel roles for PBX1 and its transcriptional network in mDAn development and PD, opening the door for new therapeutic interventions.


Assuntos
Diferenciação Celular , Proteínas de Ligação a DNA/metabolismo , Neurônios Dopaminérgicos/fisiologia , Redes Reguladoras de Genes , Doença de Parkinson/patologia , Proteínas Proto-Oncogênicas/metabolismo , Substância Negra/patologia , Humanos , Fator de Transcrição 1 de Leucemia de Células Pré-B
8.
Genes Cells ; 24(12): 836-847, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31651061

RESUMO

We used single-cell RNA sequencing (seq) on several human induced pluripotent stem (iPS) cell-derived neural stem cell (NSC) lines and one fetal brain-derived NSC line to study inherent cell type heterogeneity at proliferating neural stem cell stage and uncovered predisposed presence of neurogenic and gliogenic progenitors. We observed heterogeneity in neurogenic progenitors that differed between the iPS cell-derived NSC lines and the fetal-derived NSC line, and we also observed differences in spontaneous differentiation potential for inhibitory and excitatory neurons between the iPS cell-derived NSC lines and the fetal-derived NSC line. In addition, using a recently published glia patterning protocol we enriched for gliogenic progenitors and generated glial cells from an iPS cell-derived NSC line.


Assuntos
Células-Tronco Embrionárias Humanas/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Neurais/citologia , Neurogênese , Neuroglia/citologia , Linhagem Celular , Linhagem da Célula , Células Cultivadas , Células-Tronco Embrionárias Humanas/classificação , Humanos , Células-Tronco Pluripotentes Induzidas/classificação , Análise de Célula Única
9.
Exp Cell Res ; 383(1): 111469, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31302032

RESUMO

We generated human iPS derived neural stem cells and differentiated cells from healthy control individuals and an individual with autism spectrum disorder carrying bi-allelic NRXN1-alpha deletion. We investigated the expression of NRXN1-alpha during neural induction and neural differentiation and observed a pivotal role for NRXN1-alpha during early neural induction and neuronal differentiation. Single cell RNA-seq pinpointed neural stem cells carrying NRXN1-alpha deletion shifting towards radial glia-like cell identity and revealed higher proportion of differentiated astroglia. Furthermore, neuronal cells carrying NRXN1-alpha deletion were identified as immature by single cell RNA-seq analysis, displayed significant depression in calcium signaling activity and presented impaired maturation action potential profile in neurons investigated with electrophysiology. Our observations propose NRXN1-alpha plays an important role for the efficient establishment of neural stem cells, in neuronal differentiation and in maturation of functional excitatory neuronal cells.


Assuntos
Transtorno Autístico/patologia , Proteínas de Ligação ao Cálcio/genética , Deleção de Genes , Células-Tronco Pluripotentes Induzidas/patologia , Proteínas do Tecido Nervoso/genética , Moléculas de Adesão de Célula Nervosa/genética , Células-Tronco Neurais/patologia , Análise de Célula Única/métodos , Potenciais de Ação , Alelos , Transtorno Autístico/genética , Diferenciação Celular , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Neurais/metabolismo , Neurogênese/genética
10.
Stem Cells ; 36(12): 1816-1827, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30171748

RESUMO

Cell-based models of the blood-brain barrier (BBB) are important for increasing the knowledge of BBB formation, degradation and brain exposure of drug substances. Human models are preferred over animal models because of interspecies differences in BBB structure and function. However, access to human primary BBB tissue is limited and has shown degeneration of BBB functions in vitro. Human induced pluripotent stem cells (iPSCs) can be used to generate relevant cell types to model the BBB with human tissue. We generated a human iPSC-derived model of the BBB that includes endothelial cells in coculture with pericytes, astrocytes and neurons. Evaluation of barrier properties showed that the endothelial cells in our coculture model have high transendothelial electrical resistance, functional efflux and ability to discriminate between CNS permeable and non-permeable substances. Whole genome expression profiling revealed transcriptional changes that occur in coculture, including upregulation of tight junction proteins, such as claudins and neurotransmitter transporters. Pathway analysis implicated changes in the WNT, TNF, and PI3K-Akt pathways upon coculture. Our data suggest that coculture of iPSC-derived endothelial cells promotes barrier formation on a functional and transcriptional level. The information about gene expression changes in coculture can be used to further improve iPSC-derived BBB models through selective pathway manipulation. Stem Cells 2018;36:1816-12.


Assuntos
Barreira Hematoencefálica/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Transcriptoma/fisiologia , Diferenciação Celular , Humanos
11.
Chemistry ; 22(22): 7381-4, 2016 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-26998912

RESUMO

An efficient and practical protocol for the enantioselective cobalt-catalyzed hydrovinylation of vinylarenes with ethylene at low (1.2 bar) pressure has been developed. As precatalysts, stable [L2 CoCl2 ] complexes are employed that are activated in situ with Et2 AlCl. A modular chiral TADDOL-derived phosphine-phosphite ligand was identified that allows the conversion of a broad spectrum of substrates, including heterocyclic vinylarenes and vinylferrocene, to smoothly afford the branched products with up to 99 % ee and virtually complete regioselectivity. Even polar functional groups, such as OH, NH2 , CN, and CO2 R, are tolerated.

12.
J Neurosci ; 33(30): 12407-22, 2013 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-23884946

RESUMO

Stem cell lines that faithfully maintain the regional identity and developmental potency of progenitors in the human brain would create new opportunities in developmental neurobiology and provide a resource for generating specialized human neurons. However, to date, neural progenitor cultures derived from the human brain have either been short-lived or exhibit restricted, predominantly glial, differentiation capacity. Pluripotent stem cells are an alternative source, but to ascertain definitively the identity and fidelity of cell types generated solely in vitro is problematic. Here, we show that hindbrain neuroepithelial stem (hbNES) cells can be derived and massively expanded from early human embryos (week 5-7, Carnegie stage 15-17). These cell lines are propagated in adherent culture in the presence of EGF and FGF2 and retain progenitor characteristics, including SOX1 expression, formation of rosette-like structures, and high neurogenic capacity. They generate GABAergic, glutamatergic and, at lower frequency, serotonergic neurons. Importantly, hbNES cells stably maintain hindbrain specification and generate upper rhombic lip derivatives on exposure to bone morphogenetic protein (BMP). When grafted into neonatal rat brain, they show potential for integration into cerebellar development and produce cerebellar granule-like cells, albeit at low frequency. hbNES cells offer a new system to study human cerebellar specification and development and to model diseases of the hindbrain. They also provide a benchmark for the production of similar long-term neuroepithelial-like stem cells (lt-NES) from pluripotent cell lines. To our knowledge, hbNES cells are the first demonstration of highly expandable neuroepithelial stem cells derived from the human embryo without genetic immortalization.


Assuntos
Proliferação de Células/efeitos dos fármacos , Células-Tronco Embrionárias/citologia , Feto/citologia , Células-Tronco Neurais/citologia , Células Neuroepiteliais/citologia , Rombencéfalo/citologia , Animais , Transplante de Tecido Encefálico/métodos , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Linhagem Celular , Linhagem da Célula , Cerebelo/citologia , Técnicas de Cocultura , Fator de Crescimento Epidérmico/farmacologia , Células Alimentadoras , Feminino , Fator 2 de Crescimento de Fibroblastos/farmacologia , Humanos , Masculino , Camundongos , Cultura Primária de Células , Ratos , Ratos Sprague-Dawley , Transplante de Células-Tronco/métodos
13.
Neuroradiology ; 56(12): 1031-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25204450

RESUMO

INTRODUCTION: Perfusion magnetic resonance imaging (MRI) can be used in the pre-operative assessment of brain tumours. The aim of this prospective study was to identify the perfusion parameters from dynamic contrast-enhanced (DCE) and dynamic susceptibility contrast (DSC) perfusion imaging that could best discriminate between grade II and III gliomas. METHODS: MRI (3 T) including morphological ((T2 fluid attenuated inversion recovery (FLAIR) and T1-weighted (T1W)+Gd)) and perfusion (DCE and DSC) sequences was performed in 39 patients with newly diagnosed suspected low-grade glioma after written informed consent in this review board-approved study. Regions of interests (ROIs) in tumour area were delineated on FLAIR images co-registered to DCE and DSC, respectively, in 25 patients with histopathological grade II (n = 18) and III (n = 7) gliomas. Statistical analysis of differences between grade II and grade III gliomas in histogram perfusion parameters was performed, and the areas under the curves (AUC) from the ROC analyses were evaluated. RESULTS: In DCE, the skewness of transfer constant (k(trans)) was found superior for differentiating grade II from grade III in all gliomas (AUC 0.76). In DSC, the standard deviation of relative cerebral blood flow (rCBF) was found superior for differentiating grade II from grade III gliomas (AUC 0.80). CONCLUSIONS: Histogram parameters from k(trans) (DCE) and rCBF (DSC) could most efficiently discriminate between grade II and grade III gliomas.


Assuntos
Neoplasias Encefálicas/patologia , Glioma/patologia , Angiografia por Ressonância Magnética , Adulto , Idoso , Neoplasias Encefálicas/fisiopatologia , Circulação Cerebrovascular , Meios de Contraste , Neuroimagem Funcional , Glioma/fisiopatologia , Humanos , Angiografia por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Gradação de Tumores , Estudos Prospectivos , Adulto Jovem
14.
Twin Res Hum Genet ; 17(3): 164-76, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24735654

RESUMO

Neurodevelopmental disorders affect a substantial minority of the general population. Their origins are still largely unknown, but a complex interplay of genetic and environmental factors causing disturbances of the central nervous system's maturation and a variety of higher cognitive skills is presumed. Only limited research of rather small sample size and narrow scope has been conducted in neurodevelopmental disorders using a twin-differences design. The Roots of Autism and ADHD Twin Study in Sweden (RATSS) is an ongoing project targeting monozygotic twins discordant for categorical or dimensional autistic and inattentive/hyperactive-impulsive phenotypes as well as other neurodevelopmental disorders, and typically developing twin controls. Included pairs are 9 years of age or older, and comprehensively assessed for psychopathology, medical history, neuropsychology, and dysmorphology, as well as structural, functional, and molecular brain imaging. Specimens are collected for induced pluripotent (iPS) and neuroepithelial stem cells, genetic, gut bacteria, protein-/monoamine, and electron microscopy analyses. RATSS's objective is to generate a launch pad for novel surveys to understand the complexity of genotype-environment-phenotype interactions in autism spectrum disorder and attention-deficit hyperactivity disorder (ADHD). By October 2013, RATSS had collected data from 55 twin pairs, among them 10 monozygotic pairs discordant for autism spectrum disorder, seven for ADHD, and four for other neurodevelopmental disorders. This article describes the design, recruitment, data collection, measures, collected pairs' characteristics, as well as ongoing and planned analyses in RATSS. Potential gains of the study comprise the identification of environmentally mediated biomarkers, the emergence of candidates for drug development, translational modeling, and new leads for prevention of incapacitating outcomes.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno Autístico/epidemiologia , Doenças em Gêmeos/epidemiologia , Meio Ambiente , Gêmeos Dizigóticos/psicologia , Gêmeos Monozigóticos/psicologia , Adolescente , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtorno Autístico/genética , Transtorno Autístico/psicologia , Criança , Cognição , Doenças em Gêmeos/genética , Doenças em Gêmeos/psicologia , Feminino , Humanos , Masculino , Neuroimagem , Fenótipo , Escalas de Graduação Psiquiátrica , Suécia/epidemiologia , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adulto Jovem
15.
Ambio ; 43(7): 878-90, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24420263

RESUMO

Methylation of mercury (Hg) to highly toxic methyl Hg (MeHg), a process known to occur when organic matter (OM) decomposition leads to anoxia, is considered a worldwide threat to aquatic ecosystems and human health. We measured temporal and spatial variations in sediment MeHg, total Hg (THg), and major elements in a freshwater lagoon in Sweden polluted with Hg-laden cellulose fibers. Fiber decomposition, confined to a narrow surface layer, resulted in loss of carbon (C), uptake of nitrogen (N), phosphorus (P), and sulfur (S), and increased MeHg levels. Notably, fiber decomposition and subsequent erosion of fiber residues will cause buried contaminants to gradually come closer to the sediment-water interface. At an adjacent site where decomposed fiber accumulated, there was a gain in C and a loss of S when MeHg increased. As evidenced by correlation patterns and vertical chemical profiles, reduced S may have fueled C-fixation and Hg methylation at this site.


Assuntos
Celulose/química , Compostos de Metilmercúrio/química , Poluentes Químicos da Água/química , Água Doce/química , Estações do Ano , Suécia , Fatores de Tempo
16.
Eur J Cardiothorac Surg ; 65(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38485689

RESUMO

OBJECTIVES: Depression has been associated with increased cardiovascular morbidity and mortality. This study aimed to determine whether self-reported preoperative depressive symptoms were associated with worse long-term survival in patients undergoing cardiac surgery. METHODS: This population-based, observational cohort study included patients who had undergone cardiac surgery at Karolinska University Hospital between 2013 and 2016. Self-reported data about depressive symptoms were collected using the Patient Health Questionnaire (PHQ-9) and other patient data were collected from the institutional surgical database and medical charts. Depression was defined as a PHQ-9 score ≥10. Weighted flexible parametric survival models were used to estimate the association between self-reported preoperative depressive symptoms and all-cause mortality and to quantify absolute survival differences. RESULTS: Of the 1120 study patients, 162 (14.5%) had depressive symptoms before cardiac surgery. During a mean follow-up of 7.2 years (maximum, 9.2 years), there were 36 deaths in 1129 person-years (PYs) in the depressed group, compared to 160 deaths in 6889 PYs in the non-depressed group. In the adjusted analysis, self-reported depressive symptoms were associated with worse long-term survival (hazard ratio 1.66; 95% confidence interval 1.09-2.54) compared with no reported depressive symptoms. The absolute survival differences (% and 95% confidence interval) between the non-depressed and the depressed patients were -1.9 (-3.9 to 0.19), -5.7 (-11 to -0.01) and -9.7 (-19 to -0.4) after 1, 5 and 8 years, respectively. CONCLUSIONS: Self-reported preoperative depressive symptoms were associated with worse long-term survival following cardiac surgery and should be regarded as important as other classical risk factors.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Depressão , Humanos , Depressão/epidemiologia , Autorrelato , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Fatores de Risco , Modelos de Riscos Proporcionais
17.
Cell Stem Cell ; 31(2): 152-154, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38306990

RESUMO

COVID-19 patients often display dysfunctions of the nervous system, indicating an effect of SARS-CoV-2 on neural cells. Yang et al. now show that human stem-cell-derived dopaminergic neurons are susceptible to SARS-CoV-2, triggering inflammation and senescence. The study further identifies three FDA-approved drugs capable of reversing these cellular phenotypes.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Neurônios Dopaminérgicos , Encéfalo
18.
Intensive Crit Care Nurs ; 84: 103757, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943716

RESUMO

OBJECTIVES: Delirium is a common post-cardiac surgery complication that presents as acute changes in mental abilities with confused thinking and a lack of awareness of the surroundings. Delirium symptoms present in hyperactive- and hypoactive forms. Hypoactive delirium is often overlooked. Although nursing interventions are important in preventing and treating hypoactive delirium, studies focusing on nurses' experiences of hypoactive delirium are scarce. This study describes registered nurses' experiences of caring for patients with hypoactive delirium after cardiac surgery. RESEARCH METHODOLOGY/DESIGN: This was a qualitative descriptive study with an inductive approach. Data was collected through focus group interviews with 12 registered nurses with experience in caring for cardiac surgery patients with hypoactive delirium. The study complied with the Consolidated Criteria for Reporting Qualitative Research. SETTING: A cardiac surgery department at a Swedish University Hospital. FINDINGS: The analysis resulted in one main category; "Navigating the complexities of care when caring for patients with hypoactive delirium" and three sub-categories: "Challenges, "Nursing interventions" and "Promoting a team approach". CONCLUSION: Delirium assessment and nursing interventions are perceived as essential yet demanding. when caring for patients with hypoactive delirium. Nursing interventions like maintaining the circadian rhythm and offering emotional support need to be prioritised by the nurses, in line with the autonomy of the registered nurse's profession. Moreover, the team around the patient is crucial for detecting and treating hypoactive delirium, and it is important to involve other professionals as well as the patient's relatives. Future research is needed to develop assessment instruments that more accurately capture hypoactive delirium in the postoperative setting. IMPLICATIONS FOR CLINICAL PRACTICE: Despite the use of screening tools, nurses still experience challenges in detecting the symptoms of hypoactive delirium, indicating a need for more clinically effective screening tools for hypoactive delirium. Nursing interventions are emphasised in the care of patients with hypoactive delirium.

19.
Front Pharmacol ; 15: 1390058, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38841365

RESUMO

Preclinical transplantations using human neuroepithelial stem (NES) cells in spinal cord injury models have exhibited promising results and demonstrated cell integration and functional improvement in transplanted animals. Previous studies have relied on the generation of research grade cell lines in continuous culture. Using fresh cells presents logistic hurdles for clinical transition regarding time and resources for maintaining high quality standards. In this study, we generated a good manufacturing practice (GMP) compliant human iPS cell line in GMP clean rooms alongside a research grade iPS cell line which was produced using standardized protocols with GMP compliant chemicals. These two iPS cell lines were differentiated into human NES cells, from which six batches of cell therapy doses were produced. The doses were cryopreserved, thawed on demand and grafted in a rat spinal cord injury model. Our findings demonstrate that NES cells can be directly grafted post-thaw with high cell viability, maintaining their cell identity and differentiation capacity. This opens the possibility of manufacturing off-the-shelf cell therapy products. Moreover, our manufacturing process yields stable cell doses with minimal batch-to-batch variability, characterized by consistent expression of identity markers as well as similar viability of cells across the two iPS cell lines. These cryopreserved cell doses exhibit sustained viability, functionality, and quality for at least 2 years. Our results provide proof of concept that cryopreserved NES cells present a viable alternative to transplanting freshly cultured cells in future cell therapies and exemplify a platform from which cell formulation can be optimized and facilitate the transition to clinical trials.

20.
Adv Sci (Weinh) ; 11(25): e2401859, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38655836

RESUMO

The clinical translation of induced pluripotent stem cells (iPSCs) holds great potential for personalized therapeutics. However, one of the main obstacles is that the current workflow to generate iPSCs is expensive, time-consuming, and requires standardization. A simplified and cost-effective microfluidic approach is presented for reprogramming fibroblasts into iPSCs and their subsequent differentiation into neural stem cells (NSCs). This method exploits microphysiological technology, providing a 100-fold reduction in reagents for reprogramming and a ninefold reduction in number of input cells. The iPSCs generated from microfluidic reprogramming of fibroblasts show upregulation of pluripotency markers and downregulation of fibroblast markers, on par with those reprogrammed in standard well-conditions. The NSCs differentiated in microfluidic chips show upregulation of neuroectodermal markers (ZIC1, PAX6, SOX1), highlighting their propensity for nervous system development. Cells obtained on conventional well plates and microfluidic chips are compared for reprogramming and neural induction by bulk RNA sequencing. Pathway enrichment analysis of NSCs from chip showed neural stem cell development enrichment and boosted commitment to neural stem cell lineage in initial phases of neural induction, attributed to a confined environment in a microfluidic chip. This method provides a cost-effective pipeline to reprogram and differentiate iPSCs for therapeutics compliant with current good manufacturing practices.


Assuntos
Diferenciação Celular , Células-Tronco Pluripotentes Induzidas , Células-Tronco Neurais , Células-Tronco Neurais/citologia , Células-Tronco Neurais/fisiologia , Células-Tronco Pluripotentes Induzidas/citologia , Diferenciação Celular/fisiologia , Animais , Camundongos , Reprogramação Celular/fisiologia , Humanos , Células Cultivadas , Fibroblastos/citologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA