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1.
Cell ; 172(5): 979-992.e6, 2018 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-29456084

RESUMEN

Fragile X syndrome (FXS), the most common genetic form of intellectual disability in males, is caused by silencing of the FMR1 gene associated with hypermethylation of the CGG expansion mutation in the 5' UTR of FMR1 in FXS patients. Here, we applied recently developed DNA methylation editing tools to reverse this hypermethylation event. Targeted demethylation of the CGG expansion by dCas9-Tet1/single guide RNA (sgRNA) switched the heterochromatin status of the upstream FMR1 promoter to an active chromatin state, restoring a persistent expression of FMR1 in FXS iPSCs. Neurons derived from methylation-edited FXS iPSCs rescued the electrophysiological abnormalities and restored a wild-type phenotype upon the mutant neurons. FMR1 expression in edited neurons was maintained in vivo after engrafting into the mouse brain. Finally, demethylation of the CGG repeats in post-mitotic FXS neurons also reactivated FMR1. Our data establish that demethylation of the CGG expansion is sufficient for FMR1 reactivation, suggesting potential therapeutic strategies for FXS.


Asunto(s)
Metilación de ADN/genética , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Síndrome del Cromosoma X Frágil/genética , Edición Génica , Neuronas/patología , Animales , Proteína 9 Asociada a CRISPR/metabolismo , Epigénesis Genética , Células HEK293 , Heterocromatina/metabolismo , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Cinética , Masculino , Ratones , Neuronas/metabolismo , Fenotipo , Regiones Promotoras Genéticas , ARN Guía de Kinetoplastida/metabolismo , Expansión de Repetición de Trinucleótido/genética
2.
Sensors (Basel) ; 24(11)2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38894065

RESUMEN

A 9-10-bit adjustable and energy-efficient switching scheme for SAR ADC with one-LSB common-mode voltage variation is proposed. Based on capacitor-splitting technology and common-mode conversion techniques, the proposed switching scheme reduces the DAC switching energy by 96.41% compared to the conventional scheme. The low complexity and the one-LSB common-mode voltage offset of this scheme benefit from the simultaneous switching of the reference voltages of the capacitors corresponding to the positive array and the negative array throughout the entire reference voltage switching process, and the reference voltage of each capacitor in the scheme does not change more than two voltages. The post-layout result shows that the ADC achieves the 54.96 dB SNDR, the 61.73 dB SFDR, and the 0.67 µw power consumption with the 10-bit mode and the 48.33 dB SNDR, the 54.17 dB SFDR, and the 0.47 µw power consumption with the 9-bit mode in a 180 nm process with a 100 kS/s sampling frequency.

3.
Proc Natl Acad Sci U S A ; 117(26): 15055-15065, 2020 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-32554489

RESUMEN

Phosphocholine phosphatase-1 (PHOSPHO1) is a phosphocholine phosphatase that catalyzes the hydrolysis of phosphocholine (PC) to choline. Here we demonstrate that the PHOSPHO1 transcript is highly enriched in mature brown adipose tissue (BAT) and is further induced by cold and isoproterenol treatments of BAT and primary brown adipocytes. In defining the functional relevance of PHOPSPHO1 in BAT thermogenesis and energy metabolism, we show that PHOSPHO1 knockout mice are cold-tolerant, with higher expression of thermogenic genes in BAT, and are protected from high-fat diet-induced obesity and development of insulin resistance. Treatment of mice with the PHOSPHO1 substrate phosphocholine is sufficient to induce cold tolerance, thermogenic gene expression, and allied metabolic benefits. Our results reveal a role of PHOSPHO1 as a negative regulator of BAT thermogenesis, and inhibition of PHOSPHO1 or enhancement of phosphocholine represent innovative approaches to manage the metabolic syndrome.


Asunto(s)
Tejido Adiposo Pardo/fisiología , Monoéster Fosfórico Hidrolasas/genética , Fosforilcolina/metabolismo , Termogénesis , Adipocitos Marrones/enzimología , Adipocitos Marrones/metabolismo , Tejido Adiposo Pardo/enzimología , Animales , Frío , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Monoéster Fosfórico Hidrolasas/deficiencia
4.
Microb Pathog ; 172: 105801, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36170951

RESUMEN

Salmonella spp. poses a great threat to the livestock, food safety and public health. A recombinant swinepox virus expressing a protective antigen sseB was constructed by homologous recombination to develop a vaccine against Salmonella infection. The rSPV-sseB was verified using PCR, Western blot and indirect immunofluorescence assay. The immune responses and protective efficacy of rSPV-sseB were assessed in piglets. Forty piglets were immunized with rSPV-sseB, inactive Salmonella vaccine, wild-type SPV (wtSPV), or PBS. The results showed that the level of the sseB-specific antibody of the rSPV-sseB-vaccinated piglets was significantly higher at all time points post-vaccination than those of the inactivated Salmonella vaccine (P < 0.05), wtSPV (P < 0.001) or mock treated piglets (P < 0.001). The IL-4 and IFN-γ in the rSPV-sseB group were significantly higher than the other three groups at all post-infection time points. rSPV-sseB provided piglets with strong protection against the challenge of S. typhimurium with lethal dose. These results suggest the possibility of using recombinant swinepox virus rSPV-sseB as a promising vaccine to prevent Salmonella infection.


Asunto(s)
Infecciones por Salmonella , Vacunas contra la Salmonella , Suipoxvirus , Animales , Porcinos , Suipoxvirus/genética , Salmonella typhimurium/genética , Interleucina-4 , Vacunas Sintéticas
5.
Virol J ; 19(1): 68, 2022 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-35413989

RESUMEN

BACKGROUND: The onset and progression of cervical intraepithelial neoplasia (CIN) are closely associated with the persistent infection of high-risk HPV (especially type16), which is mainly caused by immune escape. Natural killer (NK) cells play an important role against virally infected cells and tumor cells through a fine balance of signals from multiple surface receptors. Overexpression of non-MHC-I specific inhibitory receptors TIGIT, KLRG1, Siglec-7, LAIR-1, and CD300a on NK cells correlates with cellular exhaustion and immune evasion, but these receptors have not been investigated in CIN. The aim of the present study was to examine the potential role of NK cell non-MHC-I specific inhibitory receptors expression in immune escape from HPV16(+)CIN patients. METHODS: The subset distribution, IFN-γ and TNF-α expression levels and immunophenotype of TIGIT, KLRG1, Siglec-7, LAIR-1, and CD300a of NK cells were investigated in peripheral blood mononuclear cell samples by flow cytometry from 82 women who were HPV16(+) with CIN grades 0, I, II-III or HPV(-) CIN 0. Immunohistochemistry was applied to detect the expression of ligands for NK receptors in the cervical tissues. HPV types were identified by PCR assays. RESULTS: The HPV16(+) subjects with high-grade lesions had an increased number of circulating peripheral blood CD56bright NK cells with reduced functionality and IFN-γ secretion. The expression levels of the inhibitory molecules TIGIT and KLRG1 on CD56bright NK cells increased in parallel with increasing CIN grade. In addition, TIGIT and KLRG1 related ligands, Poliovirus receptor (PVR), N-Cadherin and E-Cadherin expression level was also elevated with increasing CIN grade. CONCLUSIONS: Our results suggest that up-regulation of the inhibitory TIGIT, KLRG1 and their ligands may negatively regulate cervical CD56bright NK-mediated immunity to HPV16 and contribute to the progression of CIN. These results may facilitate the development of early-warning immune predictors and therapeutic strategies for HPV16(+) CIN based on the TIGIT and KLRG1 inhibitory pathways of NK cells.


Asunto(s)
Infecciones por Papillomavirus , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Femenino , Papillomavirus Humano 16 , Humanos , Células Asesinas Naturales , Lectinas Tipo C/genética , Leucocitos Mononucleares/metabolismo , Ligandos , Infecciones por Papillomavirus/patología , Receptores Inmunológicos/metabolismo , Lectinas Similares a la Inmunoglobulina de Unión a Ácido Siálico
6.
Alcohol Alcohol ; 55(4): 357-366, 2020 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-32363392

RESUMEN

AIMS: Ethanol is a small molecule capable of interacting with numerous targets in the brain, the mechanisms of which are complex and still poorly understood. Studies have revealed that ethanol-induced hippocampal neuronal injury is associated with oxidative stress. Grape seed procyanidin (GSP) is a new type of antioxidant that is believed to scavenge free radicals and be anti-inflammatory. This study evaluated the ability and mechanism by which the GSP improves ethanol-induced hippocampal neuronal injury. METHODS: Primary cultures of hippocampal neurons were exposed to ethanol (11, 33 and 66 mM, 1, 4, 8, 12 and 24 h) and the neuroprotective effects of GSP were assessed by evaluating the activity of superoxide dismutase (SOD), the levels of malondialdehyde (MDA) and lactate dehydrogenase (LDH) and cell morphology. RESULTS: Our results indicated that GSP prevented ethanol-induced neuronal injury by reducing the levels of MDA and LDH, while increasing the activity of SOD. In addition, GSP increased the number of primary dendrites and total dendritic length per cell. CONCLUSION: Together with previous findings, these results lend further support to the significance of developing GSP as a therapeutic tool for use in the treatment of alcohol use disorders.


Asunto(s)
Etanol/toxicidad , Hipocampo/efectos de los fármacos , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacos , Proantocianidinas/farmacología , Animales , Células Cultivadas , Hipocampo/citología , L-Lactato Deshidrogenasa/metabolismo , Malondialdehído/metabolismo , Neuronas/ultraestructura , Ratas , Ratas Sprague-Dawley , Semillas , Superóxido Dismutasa/metabolismo , Vitis
7.
Genes Dev ; 25(24): 2573-8, 2011 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-22155924

RESUMEN

Long noncoding RNAs (lncRNAs) are differentially expressed under both normal and pathological conditions, implying that they may play important biological functions. Here we examined the expression of lncRNAs during erythropoiesis and identified an erythroid-specific lncRNA with anti-apoptotic activity. Inhibition of this lncRNA blocks erythroid differentiation and promotes apoptosis. Conversely, ectopic expression of this lncRNA can inhibit apoptosis in mouse erythroid cells. This lncRNA represses expression of Pycard, a proapoptotic gene, explaining in part the inhibition of programmed cell death. These findings reveal a novel layer of regulation of cell differentiation and apoptosis by a lncRNA.


Asunto(s)
Apoptosis , Diferenciación Celular , Células Eritroides/citología , Eritropoyesis/genética , Regulación del Desarrollo de la Expresión Génica , ARN no Traducido/metabolismo , Animales , Apoptosis/genética , Proteínas Reguladoras de la Apoptosis , Proteínas Adaptadoras de Señalización CARD , Células Cultivadas , Proteínas del Citoesqueleto/metabolismo , Células Eritroides/metabolismo , Perfilación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Células HEK293 , Humanos , Ratones , Ratones Endogámicos C57BL
8.
Nucleic Acids Res ; 44(D1): D560-6, 2016 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-26626150

RESUMEN

The oncogenic transformation of normal cells into malignant, rapidly proliferating cells requires major alterations in cell physiology. For example, the transformed cells remodel their metabolic processes to supply the additional demand for cellular building blocks. We have recently demonstrated essential metabolic processes in tumor progression through the development of a methodological analysis of gene expression. Here, we present the Metabolic gEne RApid Visualizer (MERAV, http://merav.wi.mit.edu), a web-based tool that can query a database comprising ∼4300 microarrays, representing human gene expression in normal tissues, cancer cell lines and primary tumors. MERAV has been designed as a powerful tool for whole genome analysis which offers multiple advantages: one can search many genes in parallel; compare gene expression among different tissue types as well as between normal and cancer cells; download raw data; and generate heatmaps; and finally, use its internal statistical tool. Most importantly, MERAV has been designed as a unique tool for analyzing metabolic processes as it includes matrixes specifically focused on metabolic genes and is linked to the Kyoto Encyclopedia of Genes and Genomes pathway search.


Asunto(s)
Bases de Datos Genéticas , Perfilación de la Expresión Génica , Neoplasias/genética , Programas Informáticos , Línea Celular , Línea Celular Tumoral , Perfilación de la Expresión Génica/normas , Humanos , Internet , Redes y Vías Metabólicas/genética , Neoplasias/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos/normas
9.
Nature ; 476(7360): 346-50, 2011 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-21760589

RESUMEN

Cancer cells adapt their metabolic processes to drive macromolecular biosynthesis for rapid cell growth and proliferation. RNA interference (RNAi)-based loss-of-function screening has proven powerful for the identification of new and interesting cancer targets, and recent studies have used this technology in vivo to identify novel tumour suppressor genes. Here we developed a method for identifying novel cancer targets via negative-selection RNAi screening using a human breast cancer xenograft model at an orthotopic site in the mouse. Using this method, we screened a set of metabolic genes associated with aggressive breast cancer and stemness to identify those required for in vivo tumorigenesis. Among the genes identified, phosphoglycerate dehydrogenase (PHGDH) is in a genomic region of recurrent copy number gain in breast cancer and PHGDH protein levels are elevated in 70% of oestrogen receptor (ER)-negative breast cancers. PHGDH catalyses the first step in the serine biosynthesis pathway, and breast cancer cells with high PHGDH expression have increased serine synthesis flux. Suppression of PHGDH in cell lines with elevated PHGDH expression, but not in those without, causes a strong decrease in cell proliferation and a reduction in serine synthesis. We find that PHGDH suppression does not affect intracellular serine levels, but causes a drop in the levels of α-ketoglutarate, another output of the pathway and a tricarboxylic acid (TCA) cycle intermediate. In cells with high PHGDH expression, the serine synthesis pathway contributes approximately 50% of the total anaplerotic flux of glutamine into the TCA cycle. These results reveal that certain breast cancers are dependent upon increased serine pathway flux caused by PHGDH overexpression and demonstrate the utility of in vivo negative-selection RNAi screens for finding potential anticancer targets.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Genómica , Serina/biosíntesis , Animales , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular , Ciclo del Ácido Cítrico/fisiología , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Ácido Glutámico/metabolismo , Humanos , Ácidos Cetoglutáricos/metabolismo , Melanoma/enzimología , Melanoma/genética , Ratones , Trasplante de Neoplasias , Fosfoglicerato-Deshidrogenasa/genética , Fosfoglicerato-Deshidrogenasa/metabolismo , Interferencia de ARN
10.
Proc Natl Acad Sci U S A ; 111(45): 16023-8, 2014 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-25349405

RESUMEN

The onset of development is marked by two major, posttranscriptionally controlled, events: oocyte maturation (release of the prophase I primary arrest) and egg activation (release from the secondary meiotic arrest). Using quantitative mass spectrometry, we previously described proteome remodeling during Drosophila egg activation. Here, we describe our quantitative mass spectrometry-based analysis of the changes in protein levels during Drosophila oocyte maturation. This study presents the first quantitative survey, to our knowledge, of proteome changes accompanying oocyte maturation in any organism and provides a powerful resource for identifying both key regulators and biological processes driving this critical developmental window. We show that Muskelin, found to be up-regulated during oocyte maturation, is required for timely nurse cell nuclei clearing from mature egg chambers. Other proteins up-regulated at maturation are factors needed not only for late oogenesis but also completion of meiosis and early embryogenesis. Interestingly, the down-regulated proteins are predominantly involved in RNA processing, translation, and RNAi. Integrating datasets on the proteome changes at oocyte maturation and egg activation uncovers dynamics in proteome remodeling during the change from oocyte to embryo. Notably, 66 proteins likely act uniquely during late oogenesis, because they are up-regulated at maturation and down-regulated at activation. We find down-regulation of this class of proteins to be mediated partially by APC/C(CORT), a meiosis-specific form of the E3 ligase anaphase promoting complex/cyclosome (APC/C).


Asunto(s)
Proteínas de Drosophila/metabolismo , Embrión no Mamífero/metabolismo , Oocitos/metabolismo , Proteoma/metabolismo , Ciclosoma-Complejo Promotor de la Anafase/metabolismo , Animales , Drosophila melanogaster , Embrión no Mamífero/citología , Oocitos/citología , Biosíntesis de Proteínas/fisiología , Proteómica/métodos , Procesamiento Postranscripcional del ARN/fisiología
11.
Blood ; 123(4): 570-81, 2014 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-24200680

RESUMEN

Erythropoiesis is regulated at multiple levels to ensure the proper generation of mature red cells under multiple physiological conditions. To probe the contribution of long noncoding RNAs (lncRNAs) to this process, we examined >1 billion RNA-seq reads of polyadenylated and nonpolyadenylated RNA from differentiating mouse fetal liver red blood cells and identified 655 lncRNA genes including not only intergenic, antisense, and intronic but also pseudogene and enhancer loci. More than 100 of these genes are previously unrecognized and highly erythroid specific. By integrating genome-wide surveys of chromatin states, transcription factor occupancy, and tissue expression patterns, we identify multiple lncRNAs that are dynamically expressed during erythropoiesis, show epigenetic regulation, and are targeted by key erythroid transcription factors GATA1, TAL1, or KLF1. We focus on 12 such candidates and find that they are nuclear-localized and exhibit complex developmental expression patterns. Depleting them severely impaired erythrocyte maturation, inhibiting cell size reduction and subsequent enucleation. One of them, alncRNA-EC7, is transcribed from an enhancer and is specifically needed for activation of the neighboring gene encoding BAND 3. Our study provides an annotated catalog of erythroid lncRNAs, readily available through an online resource, and shows that diverse types of lncRNAs participate in the regulatory circuitry underlying erythropoiesis.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Eritrocitos/citología , Factor de Transcripción GATA1/metabolismo , Factores de Transcripción de Tipo Kruppel/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , ARN Largo no Codificante , Animales , Núcleo Celular/metabolismo , Elementos de Facilitación Genéticos , Epigénesis Genética , Células Eritroides/citología , Eritropoyesis/genética , Perfilación de la Expresión Génica , Genoma , Humanos , Hibridación Fluorescente in Situ , Células K562 , Hígado/metabolismo , Ratones , Mutación , Análisis de Secuencia por Matrices de Oligonucleótidos , Retroviridae/metabolismo , Proteína 1 de la Leucemia Linfocítica T Aguda , Factores de Transcripción
12.
Proc Natl Acad Sci U S A ; 110(9): 3387-92, 2013 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-23401553

RESUMEN

The prevalence of obesity has led to a surge of interest in understanding the detailed mechanisms underlying adipocyte development. Many protein-coding genes, mRNAs, and microRNAs have been implicated in adipocyte development, but the global expression patterns and functional contributions of long noncoding RNA (lncRNA) during adipogenesis have not been explored. Here we profiled the transcriptome of primary brown and white adipocytes, preadipocytes, and cultured adipocytes and identified 175 lncRNAs that are specifically regulated during adipogenesis. Many lncRNAs are adipose-enriched, strongly induced during adipogenesis, and bound at their promoters by key transcription factors such as peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (CEBPα). RNAi-mediated loss of function screens identified functional lncRNAs with varying impact on adipogenesis. Collectively, we have identified numerous lncRNAs that are functionally required for proper adipogenesis.


Asunto(s)
Adipogénesis/genética , ARN Largo no Codificante/metabolismo , Animales , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Teoría de la Información , Masculino , Ratones , Análisis de Secuencia por Matrices de Oligonucleótidos , Sistemas de Lectura Abierta/genética , Fenotipo , ARN Largo no Codificante/genética , Reproducibilidad de los Resultados , Transcriptoma/genética
13.
Proc Natl Acad Sci U S A ; 109(36): 14568-73, 2012 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-22904186

RESUMEN

The effects of adiponectin on hepatic glucose and lipid metabolism at transcriptional level are largely unknown. We profiled hepatic gene expression in adiponectin knockout (KO) and wild-type (WT) mice by RNA sequencing. Compared with WT mice, adiponectin KO mice fed a chow diet exhibited decreased mRNA expression of rate-limiting enzymes in several important glucose and lipid metabolic pathways, including glycolysis, tricarboxylic acid cycle, fatty-acid activation and synthesis, triglyceride synthesis, and cholesterol synthesis. In addition, binding of the transcription factor Hnf4a to DNAs encoding several key metabolic enzymes was reduced in KO mice, suggesting that adiponectin might regulate hepatic gene expression via Hnf4a. Phenotypically, adiponectin KO mice possessed smaller epididymal fat pads and showed reduced body weight compared with WT mice. When fed a high-fat diet, adiponectin KO mice showed significantly reduced lipid accumulation in the liver. These lipogenic defects are consistent with the down-regulation of lipogenic genes in the KO mice.


Asunto(s)
Adiponectina/metabolismo , Regulación de la Expresión Génica/genética , Glucosa/metabolismo , Metabolismo de los Lípidos/genética , Hígado/metabolismo , Adiponectina/genética , Tejido Adiposo/patología , Análisis de Varianza , Animales , Secuencia de Bases , Peso Corporal/genética , Inmunoprecipitación de Cromatina , ADN/metabolismo , ADN Complementario/genética , Factor Nuclear 4 del Hepatocito/metabolismo , Ratones , Ratones Noqueados , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Triglicéridos/metabolismo
14.
Food Chem ; 453: 139672, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-38805941

RESUMEN

The structure and functional properties of protein fibrils are closely related to environmental factors in fibrillation. Herein, soy protein isolate fibrils (SPIFs, 22 mg/mL) were prepared under acid-heating conditions in the presence of 100 mM metal ions (K+, Na+, Ca2+, Mg2+, and Fe3+). Except for Fe3+, fibrillation and subsequent larger fibril aggregates were promoted, ultimately leading to gel formation. Compared with K+ or Na+, the addition of Ca2+ or Mg2+ resulted in more organized SPIF structures with increased ß-sheet contents and higher ThT fluorescence intensities. Furthermore, both of them resulted in longer fibrils with an average contour length of 700-800 nm, which significantly enhanced the storage modulus. However, the presence of Fe3+ accelerated protein hydrolysis and inhibited SPIF formation, resulting in samples consistently exhibited liquid behavior. These findings provide a foundation for understanding the influence of metal ions on regulating the fibrillation and gelling properties of SPIFs.


Asunto(s)
Geles , Metales , Proteínas de Soja , Proteínas de Soja/química , Geles/química , Metales/química , Iones/química , Hidrólisis
15.
Elife ; 132024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38990919

RESUMEN

Negative memories engage a brain and body-wide stress response in humans that can alter cognition and behavior. Prolonged stress responses induce maladaptive cellular, circuit, and systems-level changes that can lead to pathological brain states and corresponding disorders in which mood and memory are affected. However, it is unclear if repeated activation of cells processing negative memories induces similar phenotypes in mice. In this study, we used an activity-dependent tagging method to access neuronal ensembles and assess their molecular characteristics. Sequencing memory engrams in mice revealed that positive (male-to-female exposure) and negative (foot shock) cells upregulated genes linked to anti- and pro-inflammatory responses, respectively. To investigate the impact of persistent activation of negative engrams, we chemogenetically activated them in the ventral hippocampus over 3 months and conducted anxiety and memory-related tests. Negative engram activation increased anxiety behaviors in both 6- and 14-month-old mice, reduced spatial working memory in older mice, impaired fear extinction in younger mice, and heightened fear generalization in both age groups. Immunohistochemistry revealed changes in microglial and astrocytic structure and number in the hippocampus. In summary, repeated activation of negative memories induces lasting cellular and behavioral abnormalities in mice, offering insights into the negative effects of chronic negative thinking-like behaviors on human health.


Asunto(s)
Conducta Animal , Hipocampo , Animales , Ratones , Masculino , Hipocampo/metabolismo , Femenino , Miedo , Memoria/fisiología , Ansiedad , Ratones Endogámicos C57BL , Neuronas/fisiología , Neuronas/metabolismo
16.
Biol Psychiatry ; 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39029776

RESUMEN

BACKGROUND: Parkinson's disease (PD) is the second most common neurodegenerative disease, following Alzheimer's. It is characterized by the aggregation of α-synuclein into Lewy bodies and Lewy neurites in the brain. Microglia-driven neuroinflammation may contribute to neuronal death in PD, however the exact role of microglia remains unclear and has been understudied. The A53T mutation in the gene coding for α-synuclein has been linked to early-onset PD, and exposure to A53T-mutant human α-synuclein increases the potential for inflammation of murine microglia. To date, its effect has not been studied in human microglia. METHODS: Here, we used 2-dimensional cultures of human iPSC-derived microglia and transplantation of these cells into the mouse brain to assess the cell-autonomous effects of the A53T mutation on human microglia. RESULTS: We found that A53T-mutant human microglia had an intrinsically increased propensity towards pro-inflammatory activation upon inflammatory stimulus. Additionally, transplanted A53T mutant microglia showed a strong decrease in catalase expression in non-inflammatory conditions, and increased oxidative stress. CONCLUSIONS: Our results indicate that A53T mutant human microglia display cell-autonomous phenotypes that may worsen neuronal damage in early-onset PD.

17.
Nat Commun ; 15(1): 471, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38212318

RESUMEN

Membrane technology using well-defined pore structure can achieve high ion purity and recovery. However, fine-tuning the inner pore structure of the separation nanofilm to be uniform and enhance the effective pore area is still challenging. Here, we report dendrimers with different peripheral groups that preferentially self-assemble in aqueous-phase amine solution to facilitate the formation of polyamide nanofilms with a well-defined effective pore range and uniform pore structure. The high permeabilities are maintained by forming asymmetric hollow nanostripe nanofilms, and their well-designed ion effective separation pore ranges show an enhancement, rationalized by molecular simulation. The self-assembled dendrimer polyamide membrane provides Cl-/SO42- selectivity more than 17 times that of its pristine polyamide counterparts, increasing from 167.9 to 2883.0. Furthermore, the designed membranes achieve higher Li purity and Li recovery compared to current state-of-the-art membranes. Such an approach provides a scalable strategy to fine-tune subnanometre structures in ion separation nanofilms.

18.
Gynecol Oncol ; 131(3): 555-60, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24060413

RESUMEN

OBJECTIVE: Recent advances suggest that precancerous lesions of pelvic serous carcinoma (PSC) originate from tubal secretory cells. The purpose of our study was to determine if increased number of secretory cells shows difference in age and location and to examine their association with serous neoplasia. MATERIALS AND METHODS: Three groups (benign control, high-risk, and PSC) of patients with matched ages were studied. The age data was stratified into 10-year intervals ranging from age 20 to older than 80. The number of secretory and ciliated cells from both tubal fimbria and ampulla segments was counted by microscopy and immunohistochemical staining methods. The data was analyzed by standard contingency table and Poisson distribution methods after age justification. RESULTS: We found that the absolute number of tubal secretory cells increased significantly with age within each age group. Age remained a significant risk factor for serous neoplasia after age adjustment. In addition, a dramatic increase of secretory cells was observed in high-risk and PSC patients. Further, secretory cell expansion (SCE) was more prevalent than secretory cell outgrowth in both fimbria and ampulla tubal segments and was significantly associated with serous neoplasia (p<0.001). CONCLUSIONS: These findings suggest that SCE could potentially serve as a sensitive biomarker for early serous carcinogenesis within the fallopian tube. Findings support a relationship between serous neoplasia and increased secretory to ciliated cell ratios. Findings also support a relationship between frequency of SCE and increasing age, presence of high-risk factors and co-existing serous cancers.


Asunto(s)
Envejecimiento/patología , Carcinogénesis/patología , Cistadenocarcinoma Seroso/patología , Trompas Uterinas/patología , Neoplasias Pélvicas/patología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Humanos , Persona de Mediana Edad , Adulto Joven
19.
Polymers (Basel) ; 15(7)2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-37050299

RESUMEN

Reverse osmosis membrane (ROM) technology has a series of advantages, such as a simple process, no secondary pollution, high efficiency, energy saving, environmental protection, and good separation and purification effects. High-performance semi-aromatic polyamide reverse osmosis membranes (ROMs) were prepared by interfacial polymerization (IP) of novel cyclopentanecarbonyl chloride (CPTC) and m-phenylenediamine (MPD) monomers. The surface morphology, hydrophilicity and charge of the ROMs were characterized by field-emission scanning electron microscopy (SEM), a contact angle tester and a solid-surface zeta potential analyzer. The effects of CPTC concentration, MPD concentration, oil-phase solvent type, IP reaction time and additive concentration on the performance of semi-aromatic polyamide ROMs were studied. SEM morphology characterization showed that the surface of the prepared polyamide ROMs presented a multinodal structure. The performance test showed that when the concentration of MPD in the aqueous phase was 2.5 wt.%, the concentration of sodium dodecylbenzene sulfonate (SDBS) was 0.2%, the residence time in the aqueous phase was 2 min, the concentration of CPTC/cyclohexane in the oil phase was 0.13 wt.%, the IP reaction was 20 s, the NaCl rejection rate of the semi-aromatic polyamide ROM was 98.28% and the flux was 65.38 L/m2·h, showing good desalination performance. Compared with an NF 90 commercial membrane, it has a good anti-BSA pollution ability.

20.
bioRxiv ; 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37693409

RESUMEN

Parkinson's disease (PD) is characterized by the aggregation of α-synuclein into Lewy bodies and Lewy neurites in the brain. Microglia-driven neuroinflammation may contribute to neuronal death in PD, however the exact role of microglia remains unclear and has been understudied. The A53T mutation in the gene coding for α-synuclein has been linked to early-onset PD, and exposure to A53T-mutant human α-synuclein increases the potential for inflammation of murine microglia. To date, its effect has not been studied in human microglia. Here, we used 2-dimensional cultures of human iPSC-derived microglia and transplantation of these cells into the mouse brain to assess the effects of the A53T mutation on human microglia. We found that A53T-mutant human microglia had an intrinsically increased propensity towards pro-inflammatory activation upon inflammatory stimulus. Additionally, A53T mutant microglia showed a strong decrease in catalase expression in non-inflammatory conditions, and increased oxidative stress. Our results indicate that A53T mutant human microglia display cell-autonomous phenotypes that may worsen neuronal damage in early-onset PD.

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