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1.
J Stroke Cerebrovasc Dis ; 32(8): 107173, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37186969

RESUMO

BACKGROUND: To examine the reasonable duration of continuous electrocardiographic monitoring (CEM) to detect AF at acute ischemic stroke. MATERIALS AND METHOD: 811 consecutive patients admitted to Tsuruga Municipal Hospital by acute ischemic stroke between April 2013 and December 2021 were enrolled in this study. Excluding 78 patients, 733 patients were analyzed by cluster analysis with SurvCART algorithm, followed by Kaplan-Meier analysis. RESULTS: The analysis provided step graphs for 8 subgroups. The duration of CEM to achieve the sensitivity of 0.8, 0.9, and 0.95 in each could be calculated. The duration of CEM to achieve the sensitivity of 0.8 are 18 days in female patients with heart failure (HF) (subgroup 1), 24 days in male patients with HF (subgroup 2), 22 days in patients without HF with arterial occlusion and pulse rate (PR) more than 91 (subgroup 3), 24 days in patients without HF with occlusion with PR less than 91 (subgroup 4), 18 days in patients without HF without occlusion with lacuna (subgroup 5), 26 days in patients without HF, occlusion, and lacuna, with arterial stenosis (subgroup 6), 15 days in patients without HF, occlusion, lacuna, and stenosis with BMI more than 21%(subgroup 7), and 44 days in patients without HF, occlusion, lacuna, stenosis and with BMI less than 21% (subgroup 8). CONCLUSIONS: Duration of CEM with the sensitivity of 0.8, 0.9, and 0.95 could be determined by presence of HF, female sex, arterial occlusion, PR more than 91/minute, presence of lacuna, presence of stenosis, and BMI more than 21%. (250).


Assuntos
Arteriopatias Oclusivas , Fibrilação Atrial , Insuficiência Cardíaca , AVC Isquêmico , Humanos , Feminino , Masculino , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Constrição Patológica , Frequência Cardíaca , Insuficiência Cardíaca/diagnóstico
2.
Bioorg Med Chem ; 64: 116763, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35487102

RESUMO

We report the discovery of a series of novel zwitterionic hPTHR1 antagonists. Optimization of lead compound 2 led to 4-[[1-[4-(2,9-dichloro-5,5-dimethyl-6-oxo-pyrido[2,3-d][1]benzazepin-7-yl)phenyl]-3-fluoro-azetidin-3-yl]methylamino]cyclohexanecarboxylic acid (19e, DS69910557), a compound with excellent potency and selectivity over activity at the human ether-a-go-go-related-gene (hERG) channel. Compound 19e demonstrated in vivo potency to decrease the plasma calcium concentration in rats upon oral administration. 2022 Elsevier Ltd. All rights reserved.


Assuntos
Benzazepinas/farmacologia , Receptor Tipo 1 de Hormônio Paratireóideo , Administração Oral , Animais , Humanos , Ratos , Relação Estrutura-Atividade
3.
Bioorg Med Chem ; 28(11): 115524, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32345459

RESUMO

Structural modification of a 1,4-benzodiazepin-2-one-based PTHR1 antagonist 5, a novel type of PTHR1 antagonist previously synthesized in our laboratories, yielded compound 10, which had better chemical stability than compound 5. Successive optimization of the lead 10 improved aqueous solubility, metabolic stability, and animal pharmacokinetics, culminating in the identification of DS37571084 (12). Our study paves the way for the discovery of novel and orally bioavailable PTHR1 antagonists.


Assuntos
Descoberta de Drogas , Receptor Tipo 1 de Hormônio Paratireóideo/antagonistas & inibidores , Administração Oral , Animais , Disponibilidade Biológica , Relação Dose-Resposta a Droga , Humanos , Masculino , Microssomos Hepáticos/química , Microssomos Hepáticos/metabolismo , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Receptor Tipo 1 de Hormônio Paratireóideo/metabolismo , Relação Estrutura-Atividade
4.
Bioorg Med Chem ; 28(6): 115348, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-32046916

RESUMO

A novel series of spiroindoline derivatives was discovered for use as inducers of oligodendrocyte progenitor cell (OPC) differentiation, resulting from optimization of screening hit 1. Exploration of structure-activity relationships led to compound 18, which showed improved potency (rOPC EC50 = 0.0032 µM). Furthermore, oral administration of compound 18 significantly decreased clinical severity in an experimental autoimmune encephalomyelitis (EAE) model.


Assuntos
Descoberta de Drogas , Encefalomielite Autoimune Experimental/tratamento farmacológico , Indóis/farmacologia , Células Precursoras de Oligodendrócitos/efeitos dos fármacos , Compostos de Espiro/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Encefalomielite Autoimune Experimental/patologia , Feminino , Indóis/síntese química , Indóis/química , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Ratos , Ratos Wistar , Compostos de Espiro/síntese química , Compostos de Espiro/química , Relação Estrutura-Atividade
5.
Bioorg Med Chem Lett ; 29(18): 2613-2616, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-31383587

RESUMO

The discovery and optimization of a novel series of PTHR1 antagonists are described. Starting from known PTHR1 antagonists, we identified more potent 1,4-benzodiazepin-2-one derivatives by means of a scaffold-hopping approach. The representative compound 23 (DS08210767) exhibited nanomolar-level PTHR1 antagonist activity and potential oral bioavailability in a pharmacokinetic study.


Assuntos
Benzodiazepinonas/farmacologia , Descoberta de Drogas , Receptor Tipo 1 de Hormônio Paratireóideo/antagonistas & inibidores , Benzodiazepinonas/síntese química , Benzodiazepinonas/química , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Receptor Tipo 1 de Hormônio Paratireóideo/metabolismo , Relação Estrutura-Atividade
6.
Br J Neurosurg ; 33(2): 219-221, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28421822

RESUMO

A 57-year-old woman was diagnosed as a Rathke cleft cyst (RCC). Endoscopic transsphenoidal surgery (TSS) was performed uneventfully. She developed subarachnoid haemorrhage on postoperative day 3. The vessels adhered the cyst had been pulled into the pituitary fossa, causing an aneurysm.


Assuntos
Aneurisma Roto/etiologia , Artéria Carótida Interna , Cistos do Sistema Nervoso Central/cirurgia , Aneurisma Roto/cirurgia , Descompressão Cirúrgica/métodos , Feminino , Humanos , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Neuroendoscopia , Hipófise , Sela Túrcica , Hemorragia Subaracnóidea/etiologia , Resultado do Tratamento
7.
J Surg Res ; 227: 119-129, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29804843

RESUMO

BACKGROUND: The present study aimed to evaluate whether bioengineered mouse islet cell sheets can be used for the treatment of diabetes mellitus. METHODS: Isolated mouse pancreatic islets were dispersed, and cells were plated on temperature-responsive culture plates coated with iMatrix-551. On day 3 of culture, the sheets were detached from the plates and used for further analysis or transplantation. The following parameters were assessed: (1) morphology, (2) expression of ß-cell-specific transcription factors and other islet-related proteins, (3) methylation level of the pancreatic duodenal homeobox-1 (Pdx-1) promoter, as determined by bisulfite sequencing, and (4) levels of serum glucose after transplantation of one or two islet cell sheets into the abdominal cavity of streptozotocin-induced diabetic severe combined immunodeficiency mice. RESULTS: From each mouse, we recovered approximately 233.3 ± 12.5 islets and 1.4 ± 0.1 × 105 cells after dispersion. We estimate that approximately 68.2% of the cells were lost during dispersion. The viability of recovered single cells was 91.3 ± 0.9%. The engineered islet cell sheets were stable, but the messenger RNA levels of various ß-cell-specific transcription factors were significantly lower than those of primary islets, whereas Pdx-1 promoter methylation and the expression of NeuroD, Pdx-1, and glucagon proteins were similar between sheets and islets. Moreover, transplantation of islet cell sheets did not revert serum hyperglycemia in any of the recipient mice. CONCLUSIONS: Engineering effective islet cell sheets require further research efforts, as the currently produced sheets remain functionally inferior compared with primary islets.


Assuntos
Diabetes Mellitus Experimental/terapia , Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/metabolismo , Cultura Primária de Células/métodos , Engenharia Tecidual/métodos , Cavidade Abdominal/cirurgia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Glicemia , Sobrevivência Celular , Células Cultivadas , Metilação de DNA , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/induzido quimicamente , Glucagon/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Hiperglicemia/sangue , Hiperglicemia/terapia , Insulina , Camundongos , Camundongos SCID , Proteínas do Tecido Nervoso/metabolismo , Cultura Primária de Células/instrumentação , Regiões Promotoras Genéticas/genética , Estreptozocina/toxicidade , Transativadores/genética , Transativadores/metabolismo , Resultado do Tratamento
8.
Kyobu Geka ; 71(2): 98-101, 2018 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-29483461

RESUMO

A 53-year-old man with a penetrating trauma was admitted to our hospital. Thoracoabdominal computed tomography (CT) on admission showed left diaphragmatic injury and peritoneal fat in the left thoracic cavity. Under a diagnosis of the traumatic diaphragmatic injury, an emergency operation was performed, and the left diaphragm was repaired. No other injuries were found in the thoracic and abdominal organs by thoraco-laparoscopic observation. The postoperative course was uneventful, and the patient left hospital on the 14th day after surgery. In case of the diaphragm injury, it is important to confirm the probable injuries of other organs by thoraco-laparoscopic observation.


Assuntos
Diafragma/cirurgia , Ferimentos Penetrantes/cirurgia , Diafragma/lesões , Drenagem , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Toracoscópios , Cicatrização
9.
J Reprod Dev ; 63(2): 157-165, 2017 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-28111381

RESUMO

DNA methylation in transcriptional regulatory regions is crucial for gene expression. The DNA methylation status of the edges of CpG islands, called CpG island shore, is involved in tissue/cell-type-specific gene expression. Haploinsufficiency diseases are caused by inheritance of one mutated null allele and are classified as autosomal dominant. However, in the same pedigree, phenotypic variances are observed despite the inheritance of the identical mutated null allele, including Fibrillin1 (FBN1), which is responsible for development of the haploinsufficient Marfan disease. In this study, we examined the relationship between gene expression and DNA methylation patterns of the FBN1 CpG island shore focusing on transcriptionally active hypomethylated alleles (Hypo-alleles). No difference in the DNA methylation level of FBN1 CpG island shore was observed in porcine fetal fibroblast (PFF) and the liver, whereas FBN1 expression was higher in PFF than in the liver. However, Hypo-allele ratio of the FBN1 CpG island shore in PFF was higher than that in the liver, indicating that Hypo-allele ratio of the FBN1 CpG island shore likely correlated with FBN1 expression level. In addition, oocyte-derived DNA hypermethylation in preimplantation embryos was erased until the blastocyst stage, and re-methylation of the FBN1 CpG island shore was observed with prolonged in vitro culture of blastocysts. These results suggest that the establishment of the DNA methylation pattern within the FBN1 CpG island shore occurs after the blastocyst stage, likely during organogenesis. In conclusion, Hypo-allele ratios of the FBN1 CpG island shore correlated with FBN1 expression levels in porcine tissues.


Assuntos
Blastocisto/metabolismo , Ilhas de CpG/fisiologia , Metilação de DNA , Fibrilina-1/genética , Alelos , Animais , Feminino , Fertilização in vitro/veterinária , Fibrilina-1/metabolismo , Fibroblastos/metabolismo , Fígado/metabolismo , Regiões Promotoras Genéticas , Suínos
10.
Br J Neurosurg ; 31(6): 641-647, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28830253

RESUMO

PURPOSE: Complete obliteration of treated arteriovenous malformations (AVMs) can be diagnosed only by confirming the disappearance of arterio-venous (A-V) shunts with invasive catheter angiography. The authors evaluated whether non-invasive arterial spin labeling (ASL) magnetic resonance (MR) imaging can be used to diagnose the obliteration of AVMs facilitate the diagnosis of AVM obliteration after treatment with stereotactic radiosurgery (SRS). MATERIAL AND METHODS: Seven patients with a cerebral AVM treated by SRS were followed up with ASL images taken with a 3T-MR unit, and received digital subtraction angiography (DSA) after the AVM had disappeared on ASL images. Three patients among the seven received DSA also after the postradiosurgical AVM had disappeared on conventional MR images but A-V shunt was residual on ASL images. Four patients among the seven received contrast-enhanced (CE) MR imaging around the same period as DSA. RESULTS: ASL images could visualize postradiosurgical residual A-V shunts clearly. In all seven patients, DSA after the disappearance of A-V shunts on ASL images demonstrated no evidence of A-V shunts. In all three patients, DSA after the AVM had disappeared on conventional MR images but not on ASL images demonstrated residual A-V shunt. CE MR findings of AVMs treated by SRS did not correspond with DSA findings in three out of four patients. CONCLUSIONS: Findings of radiosurgically treated AVMs on ASL images corresponded with those on DSA. The results of this study suggest that ASL imaging can be utilized to follow up AVMs after SRS and to decide their obliteration facilitate to decide the precise timing of catheter angiography for the final diagnosis of AVM obliteration after SRS.


Assuntos
Malformações Arteriovenosas Intracranianas/cirurgia , Radiocirurgia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Digital/métodos , Espectroscopia de Ressonância de Spin Eletrônica , Feminino , Humanos , Malformações Arteriovenosas Intracranianas/patologia , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Curva ROC , Estudos Retrospectivos , Adulto Jovem
11.
Reprod Med Biol ; 16(4): 337-348, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29259487

RESUMO

Purpose: Prenatal exposure to environmental chemicals is a growing concern, because such exposures have been shown to be associated with various diseases. The levels of chemicals and heavy metals in maternal blood, cord blood, maternal urine and amniotic fluid in Japanese pregnant women were investigated. Methods: A total of 145 women, including 14 fetal growth restriction cases, were included in the present study. The levels of phthalates (di[2-ethylhexyl]phthalate and mono[2-ethylhexyl]phthalate), perfluorinated compounds (perfluorooctane sulfonate, perfluorohexanoic acid, perfluorooctanoic acid, and perfluorononanoic acid), pesticides (dimethylphosphate, dimethylthiophosphate, diethylphosphate, diethylthiophosphate, 3-phenoxybenzoic acid, and octachlorodipropyl ether), bisphenol A, nicotine (nicotine, nornicotine, cotinine, norcotinine, and trans-3'-hydroxycotinine), polybrominated diphenyl ethers, and heavy metals were measured. The relationship between fetal growth and the levels of chemicals and heavy metals were investigated. Results: Phthalates, perfluorinated compounds, pesticides, polybrominated diphenyl ethers, and heavy metals were detected in high frequency, whereas nicotine and bisphenol A were almost negative. Phthalates, perfluorinated compounds, and several heavy metals were transferred to the fetus. High perfluorononanoic acid levels in the maternal blood and cord blood, and low perfluorooctanoic acid level in the cord blood were significantly and negatively associated with fetal growth. Conclusions: The present study showed that pregnant women in Japan and their fetuses are exposed to a variety of chemicals and heavy metals.

12.
J Reprod Dev ; 62(5): 511-520, 2016 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-27396383

RESUMO

Genetically modified pigs that express fluorescent proteins such as green and red fluorescent proteins have become indispensable biomedical research tools in recent years. Cell or tissue transplantation studies using fluorescent markers should be conducted, wherein the xeno-antigenicity of the fluorescent proteins does not affect engraftment or graft survival. Thus, we aimed to create a transgenic (Tg)-cloned pig that was immunologically tolerant to fluorescent protein antigens. In the present study, we generated a Tg-cloned pig harboring a derivative of Plum modified by a single amino acid substitution in the chromophore. The cells and tissues of this Tg-cloned pig expressing the modified Plum (mPlum) did not fluoresce. However, western blot and immunohistochemistry analyses clearly showed that the mPlum had the same antigenicity as Plum. Thus, we have obtained primary proof of principle for creating a cloned pig that is immunologically tolerant to fluorescent protein antigens.


Assuntos
Animais Geneticamente Modificados , Técnicas de Transferência Nuclear , Transgenes , Animais , Antígenos/metabolismo , Núcleo Celular/metabolismo , Clonagem Molecular , Metilação de DNA , Feminino , Fibroblastos/metabolismo , Citometria de Fluxo , Fluorescência , Vetores Genéticos , Genótipo , Sobrevivência de Enxerto , Imuno-Histoquímica , Substâncias Luminescentes/química , Suínos
13.
Nat Cell Biol ; 9(1): 64-71, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17143267

RESUMO

DNA methylation is an important means of epigenetic gene regulation and must be carefully controlled as a prerequisite for normal early embryogenesis. Although global demethylation occurs soon after fertilization, it is not evenly distributed throughout the genome. Genomic imprinting and epigenetic asymmetry between parental genomes, that is, delayed demethylation of the maternal genome after fertilization, are clear examples of the functional importance of DNA methylation. Here, we show that PGC7/Stella, a maternal factor essential for early development, protects the DNA methylation state of several imprinted loci and epigenetic asymmetry. After determining that PGC7/Stella binds to Ran binding protein 5 (RanBP5; a nuclear transport shuttle protein), mutant versions of the two proteins were used to examine exactly when and where PGC7/Stella functions within the cell. It is likely that PGC7/Stella protects the maternal genome from demethylation only after localizing to the nucleus, where it maintains the methylation of several imprinted genes. These results demonstrate that PGC7/Stella is indispensable for the maintenance of methylation involved in epigenetic reprogramming after fertilization.


Assuntos
Metilação de DNA , Desenvolvimento Embrionário/genética , Epigênese Genética , Regulação da Expressão Gênica no Desenvolvimento , Proteínas/fisiologia , Animais , Células COS , Linhagem Celular , Núcleo Celular/metabolismo , Chlorocebus aethiops , Proteínas Cromossômicas não Histona , Feminino , Fertilização/genética , Humanos , Masculino , Camundongos , Proteínas/genética , Proteínas/metabolismo , Transfecção
14.
No Shinkei Geka ; 42(2): 137-42, 2014 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-24501187

RESUMO

We report the usefulness of 3D-FIESTA magnetic resonance imaging(MRI)for the detection of oculomotor nerve palsy in a case of pituitary apoplexy. A 69-year-old man with diabetes mellitus presented with complete left-side blepharoptosis. Computed tomography of the brain showed an intrasellar mass with hemorrhage. MRI demonstrated a pituitary adenoma with a cyst toward the left cavernous sinus, which was diagnosed as pituitary apoplexy. 3D-FIESTA revealed that the left oculomotor nerve was compressed by the cyst. He underwent trans-sphenoid tumor resection at 5 days after his hospitalization. Post-operative 3D-FIESTA MRI revealed decrease in compression of the left oculomotor nerve by the cyst. His left oculomotor palsy recovered completely within a few months. Oculomotor nerve palsy can occur due to various diseases, and 3D-FIESTA MRI is useful for detection of oculomotor nerve compression, especially in the field of parasellar lesions.


Assuntos
Artrogripose/cirurgia , Complicações do Diabetes , Neuropatia Hereditária Motora e Sensorial/cirurgia , Imageamento por Ressonância Magnética , Doenças do Nervo Oculomotor/cirurgia , Nervo Oculomotor/patologia , Apoplexia Hipofisária/cirurgia , Neoplasias Hipofisárias/cirurgia , Idoso , Artrogripose/etiologia , Neuropatia Hereditária Motora e Sensorial/etiologia , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética/métodos , Masculino , Nervo Oculomotor/cirurgia , Doenças do Nervo Oculomotor/diagnóstico , Doenças do Nervo Oculomotor/etiologia , Doenças do Nervo Oculomotor/patologia , Apoplexia Hipofisária/diagnóstico , Apoplexia Hipofisária/patologia , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/patologia
15.
Genesis ; 51(11): 763-76, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23913699

RESUMO

Porcine induced pluripotent stem cells (iPSCs) provide useful information for translational research. The quality of iPSCs can be assessed by their ability to differentiate into various cell types after chimera formation. However, analysis of chimera formation in pigs is a labor-intensive and costly process, necessitating a simple evaluation method for porcine iPSCs. Our previous study identified mouse embryonic stem cell (ESC)-specific hypomethylated loci (EShypo-T-DMRs), and, in this study, 36 genes selected from these were used to evaluate porcine iPSC lines. Based on the methylation profiles of the 36 genes, the iPSC line, Porco Rosso-4, was found closest to mouse pluripotent stem cells among 5 porcine iPSCs. Moreover, Porco Rosso-4 more efficiently contributed to the inner cell mass (ICM) of blastocysts than the iPSC line showing the lowest reprogramming of the 36 genes (Porco Rosso-622-14), indicating that the DNA methylation profile correlates with efficiency of ICM contribution. Furthermore, factors known to enhance iPSC quality (serum-free medium with PD0325901 and CHIR99021) improved the methylation status at the 36 genes. Thus, the DNA methylation profile of these 36 genes is a viable index for evaluation of porcine iPSCs.


Assuntos
Metilação de DNA , Células-Tronco Embrionárias/metabolismo , Loci Gênicos , Células-Tronco Pluripotentes Induzidas/metabolismo , Porco Miniatura/embriologia , Suínos/embriologia , Animais , Massa Celular Interna do Blastocisto/metabolismo , Linhagem Celular , Quimera , Embrião de Mamíferos , Expressão Gênica , Genes , Camundongos , Pesquisa Translacional Biomédica
16.
Proc Natl Acad Sci U S A ; 107(24): 10926-31, 2010 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-20508149

RESUMO

Transcription networks composed of various transcriptional factors specifically expressed in undifferentiated embryonic stem (ES) cells have been implicated in the regulation of pluripotency in ES cells. However, the molecular mechanisms responsible for self-renewal, maintenance of pluripotency, and lineage specification during differentiation of ES cells are still unclear. The results of this study demonstrate that a phosphorylation-dependent chromatin relaxation factor, transcriptional intermediary factor-1beta (TIF1beta), is a unique regulator of the pluripotency of ES cells and regulates Oct3/4-dependent transcription in a phosphorylation-dependent manner. TIF1beta is specifically phosphorylated in pluripotent mouse ES cells at the C-terminal serine 824, which has been previously shown to induce chromatin relaxation. Phosphorylated TIF1beta is partially colocalized at the activated chromatin markers, and forms a complex with the pluripotency-specific transcription factor Oct3/4 and subunits of the switching defective/sucrose nonfermenting, ATP-dependent chromatin remodeling complex, Smarcd1 [corrected], Brg-1, and BAF155, all of which are components of an ES-specific chromatin remodeling complex, esBAF. Phosphorylated TIF1beta specifically induces ES cell-specific genes and enables prolonged maintenance of an undifferentiated state in mouse ES cells. Moreover, TIF1beta regulates the reprogramming process of somatic cells in a phosphorylation-dependent manner. Our results suggest that TIF1beta provides a phosphorylation-dependent, bidirectional platform for specific transcriptional factors and chromatin remodeling enzymes that regulate the cell differentiation process and the pluripotency of stem cells.


Assuntos
Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Proteínas Nucleares/metabolismo , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Proteínas Repressoras/metabolismo , Substituição de Aminoácidos , Animais , Diferenciação Celular , Montagem e Desmontagem da Cromatina , Camundongos , Mutagênese Sítio-Dirigida , Neurônios/citologia , Neurônios/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Fosforilação , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Repressoras/química , Proteínas Repressoras/genética , Serina/química , Fatores de Transcrição/metabolismo , Proteína 28 com Motivo Tripartido
17.
J Toxicol Sci ; 48(11): 571-583, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37914285

RESUMO

Various chemicals, including pesticides, heavy metals, and metabolites of tobacco, have been detected in fetal environment. Fetuses are exposed to these chemicals at relatively low concentrations; however, their risk of developing neurological and behavioral disorders increases after birth. We aimed to evaluate the effects of five chemicals (diethylphosphate, cotinine, octachlorodipropyl ether, mercury, and selenium) detected in the serum of pregnant mothers on neural development using human neurospheres (NSphs) differentiated from induced pluripotent stem cells. Exposure to each chemical at serum concentrations revealed no effects on NSph development. However, combined exposure to the five chemicals caused a significant decrease in NSph size and altered gene expression and neural differentiation. Thus, we next focused on DNA methylation to investigate changes in NSph properties caused by chemical exposure. Combined exposure to chemicals had extremely small effects on the DNA methylation status of NSphs at individual gene loci. However, stochastic changes in methylation status caused by chemical exposure were significantly accumulated throughout the entire genome. These results suggest that the five chemicals acted as epimutagens that alter the epigenetic status during human neural development at the biological level. Taken together, we showed for the first time, the epimutagen-induced alterations in neural differentiation at serum concentrations using an in vitro human neuronal model.


Assuntos
Epigênese Genética , Células-Tronco Pluripotentes Induzidas , Gravidez , Feminino , Humanos , Mutagênicos/metabolismo , Metilação de DNA , Diferenciação Celular/genética
18.
NMC Case Rep J ; 10: 227-233, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37621749

RESUMO

A 47-year-old man presented with sudden-onset headache and Fisher group 3 subarachnoid hemorrhage. The World Federation of Neurological Surgeons grade was II. Digital subtraction angiography (DSA) only showed a vessel wall irregularity in the A1 segment of the right anterior cerebral artery (ACA), but an obvious bleeding source was not detected. Repeat angiography showed a tiny aneurysmal dilatation in the A1 segment with an intimal flap. The aneurysm enlarged on subsequent angiograms. Dissecting aneurysm was diagnosed, and the patient underwent internal trapping of the A1 segment to prevent rerupture. Postoperative DSA showed complete obliteration of the dissected segment. Magnetic resonance imaging showed a clinically silent cerebral infarction in the territory of the A1 segment perforators. Parent vessel occlusion for a dissected A1 segment can be effective, provided that sufficient collateral blood flow from the contralateral ACA is observed. We recommend endovascular trapping in this setting and hope that fellow clinicians select this approach for this rare pathology.

19.
Regen Ther ; 21: 620-630, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36514370

RESUMO

Introduction: Human induced pluripotent stem cells (hiPSCs) are useful tools for reproducing neural development in vitro. However, each hiPSC line has a different ability to differentiate into specific lineages, known as differentiation propensity, resulting in reduced reproducibility and increased time and funding requirements for research. To overcome this issue, we searched for predictive signatures of neural differentiation propensity of hiPSCs focusing on DNA methylation, which is the main modulator of cellular properties. Methods: We obtained 32 hiPSC lines and their comprehensive DNA methylation data using the Infinium MethylationEPIC BeadChip. To assess the neural differentiation efficiency of these hiPSCs, we measured the percentage of neural stem cells on day 7 of induction. Using the DNA methylation data of undifferentiated hiPSCs and their measured differentiation efficiency into neural stem cells as the set of data, and HSIC Lasso, a machine learning-based nonlinear feature selection method, we attempted to identify neural differentiation-associated differentially methylated sites. Results: Epigenome-wide unsupervised clustering cannot distinguish hiPSCs with varying differentiation efficiencies. In contrast, HSIC Lasso identified 62 CpG sites that could explain the neural differentiation efficiency of hiPSCs. Features selected by HSIC Lasso were particularly enriched within 3 Mbp of chromosome 5, harboring IRX1, IRX2, and C5orf38 genes. Within this region, DNA methylation rates were correlated with neural differentiation efficiency and were negatively correlated with gene expression of the IRX1/2 genes, particularly in female hiPSCs. In addition, forced expression of the IRX1/2 impaired the neural differentiation ability of hiPSCs in both sexes. Conclusion: We for the first time showed that the DNA methylation state of the IRX1/2 genes of hiPSCs is a predictive biomarker of their potential for neural differentiation. The predictive markers for neural differentiation efficiency identified in this study may be useful for the selection of suitable undifferentiated hiPSCs prior to differentiation induction.

20.
Genes Cells ; 15(6): 607-18, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20477876

RESUMO

DNA methylation profile, consisting of tissue-dependent and differentially methylated regions (T-DMRs), has elucidated tissue-specific gene function in mouse tissues. Here, we identified and profiled thousands of T-DMRs in embryonic stem cells (ESCs), embryonic germ cells (EGCs) and induced pluripotent stem cells (iPSCs). T-DMRs of ESCs compared with somatic tissues well illustrated gene function of ESCs, by hypomethylation at genes associated with CpG islands and nuclear events including transcriptional regulation network of ESCs, and by hypermethylation at genes for tissue-specific function. These T-DMRs in EGCs and iPSCs showed DNA methylation similar to ESCs. iPSCs, however, showed hypomethylation at a considerable number of T-DMRs that were hypermethylated in ESCs, suggesting existence of traceable progenitor epigenetic information. Thus, DNA methylation profile of T-DMRs contributes to the mechanism of pluripotency, and can be a feasible solution for identification and evaluation of the pluripotent cells.


Assuntos
Metilação de DNA , Perfilação da Expressão Gênica/métodos , Genoma/genética , Células-Tronco Pluripotentes/metabolismo , Animais , Análise por Conglomerados , Ilhas de CpG/genética , Células-Tronco Embrionárias/citologia , Camundongos , Modelos Genéticos , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase
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