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Rhenium disulfide (ReS2) is a promising piezoelectric catalyst due to its excellent electron transfer ability and abundant unsaturated sites. The 1T' phase structure leads to the evolution of ReS2 into a centrosymmetric spatial structure, which restricts its application in piezoelectric catalysis. Herein, we propose a controllable defect engineering strategy to trigger the piezoelectric response of ReS2. The introduction of vacancy defects disrupts the initial centrosymmetric structure, which breaks the piezoelectric polarization bond and generates piezoelectric properties. By using transmission electron microscopy, we characterized it at the atomic scale and determined that vacancy defects contribute to an excellent piezoelectric property through first-principles calculations. Notably, the piezoelectric coefficient of the catalyst with 40 s-etching (ReS2@C-40) is 23.07 pm/V, an order of magnitude greater than other transition metal dichalcogenides. It demonstrated the feasibility of optimizing piezoelectric properties by increasing the conformational asymmetry. Based on its remarkable piezoelectric activity, ReS2@C-40 exhibits highly efficient piezo-photocatalytic synergistic sterilization performance with 99.99% eradication of Escherichia coli and 96.67% of Staphylococcus aureus within 30 min. This pioneering research on the coupling effect of ReS2 in piezoelectric catalysis and photocatalysis provides ideas for the development of piezo-photocatalysts and efficient water purification technologies.
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BACKGROUND: Toll-like receptors (TLRs) are critical sensors for the conservation of bacterial molecules and play a key role in host defense against pathogens. The effect of TLRs on the maintenance of diabetic nephropathy (DN) and resistance to infection has been investigated; however, the detailed effects of TLR9 on DN development remain elusive. METHODS: We performed quantitative reverse transcription-polymerase chain reaction and western blotting to detect TLR9 expression levels in the kidneys of experimental mice (db/db) and high-glucose-treated mouse mesangial cell strains (MCs). RESULTS: TLR9 expression was found to be remarkably upregulated in the kidneys of experimental mice (db/db) and MCs cultivated under hyperglycemic conditions. Moreover, knockdown of TLR9 could restrain NF-kB viability and downregulate the NLRP3 inflammasome in high glucose-treated MCs. TLR9 inhibition also alleviated inflammation and apoptosis, which was reversed by the addition of the NF-κB activator, betulinic acid. Furthermore, depleted TLR9 levels restrained NF-κB viability and NLRP3 expression and reduced kidney inflammation, microalbuminuria discharge, blood sugar level, and glomerular damage in experimental mice (db/db) kidneys. Conclusions These findings offer novel insights into the regulation of TLR9 via the nuclear factor-kB/NOD-, LRR-, and pyrin domain-containing protein 3 inflammasome inflammation pathways in DN progression.
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OBJECTIVES: To analyze the clinical characteristics and prognosis of children with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis and to provide a basis for early clinical identification of this disease. METHODS: The clinical data of 42 cases of anti-NMDAR encephalitis at Department of Pediatrics, Second Xiangya Hospital, Central South University from January 2015 to March 2018 were collected. The clinical features and followed-up outcomes were analyzed retrospectively. RESULTS: There were 15 cases (35.7%) of males and 27 cases (64.3%) of females in 42 children, with a ratio of 1ê1.8. They were aged from 4 months to 17 years, with an average of (9.20±4.66) years. The most common initial symptoms were seizures (47.6%, 20/42) and mental behavior disorder (35.7%, 15/42). During the course of the disease, 85.7% patients(36/42) had mental and behavior disorder, 85.7% patients (36/42) had epilepsy, 76.2% (32/42) had speech disorder, 66.7% patients (28/42) had dyskinesia, 66.7% patients (28/42) had the decreased level of consciousness, 61.9% patients (26/42) had autonomic instability, and 57.1% (24/42) patients had sleep disorder. All the children had positive antibody against NMDA receptor resistance encephalitis in cerebrospinal fluid. Head MRI showed the abnormal incidence was 50.0% (21/42), and the lesions involved in parietal lobe, frontal lobe, temporal lobe, occipital lobe, midbrain, thalamus, basal ganglia and optic nerve. There was a patient with optic nerve damage combined with myelin oligodendrocyte glycoprotein (MOG) antibody positive. Forty cases were examined by electroencephalogram (EEG), 92.5% cases (37/40) were abnormal, mainly showing diffuse slow waves, and δ brushes could be seen in severe cases. And there was 1 patient (2.4%) complicated with mesenteric teratoma. The mRS score (2.14±1.46) at discharge was significantly lower than the highest mRS score (3.88±1.38) during hospitalization (P<0.05). After 3-39 months of follow-up, mRS score at 3 months after discharge was only 0.81±1.29, which was still improved compared with that at discharge, 76.2% cases (32/42) experienced complete or near-complete recovery (mRS score≤2), and 4.8% (2/42) cases relapsed. There was no mortality; the initial time of immunotherapy and the highest mRS score in the course of the disease were the factors affecting the prognosis. The earlier the starting time for immunotherapy and the lower mRS score in the course of the disease were, the better the prognosis was. CONCLUSIONS: Seizures, mental and behavior disorder, dyskinesias, speech disorder and autonomic instability are common clinical manifestations of anti-NMDAR encephalitis in children. The effect of immunotherapy is significant, and the time to start immunotherapy and the severity of the disease are important factors affecting the prognosis. Anti-NMDAR encephalitis can be combined with other autoantibodies, but its clinical significance and mechanism need further study.
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Encefalitis Antirreceptor N-Metil-D-Aspartato , Adolescente , Autoanticuerpos , Niño , Preescolar , Electroencefalografía , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Receptores de N-Metil-D-Aspartato , Estudios RetrospectivosRESUMEN
Understanding the relative contributions of genetic and epigenetic abnormalities to acute myeloid leukemia (AML) should assist integrated design of targeted therapies. In this study, we generated induced pluripotent stem cells (iPSCs) from AML patient samples harboring MLL rearrangements and found that they retained leukemic mutations but reset leukemic DNA methylation/gene expression patterns. AML-iPSCs lacked leukemic potential, but when differentiated into hematopoietic cells, they reacquired the ability to give rise to leukemia in vivo and reestablished leukemic DNA methylation/gene expression patterns, including an aberrant MLL signature. Epigenetic reprogramming was therefore not sufficient to eliminate leukemic behavior. This approach also allowed us to study the properties of distinct AML subclones, including differential drug susceptibilities of KRAS mutant and wild-type cells, and predict relapse based on increased cytarabine resistance of a KRAS wild-type subclone. Overall, our findings illustrate the value of AML-iPSCs for investigating the mechanistic basis and clonal properties of human AML.
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Diferenciación Celular , Células Madre Pluripotentes Inducidas/citología , Leucemia Mieloide Aguda/patología , Modelos Biológicos , Crisis Blástica/patología , Línea Celular Tumoral , Linaje de la Célula , Forma de la Célula , Reprogramación Celular , Aberraciones Cromosómicas , Células Clonales , Metilación de ADN/genética , Epigénesis Genética , Perfilación de la Expresión Génica , Regulación Leucémica de la Expresión Génica , Células HEK293 , Hematopoyesis/genética , Humanos , Leucemia Mieloide Aguda/genética , Terapia Molecular Dirigida , Mutación/genética , Invasividad Neoplásica , FenotipoRESUMEN
UNLABELLED: Numerous studies in multiple systems support that histone H3 lysine 36 dimethylation (H3K36me2) is associated with transcriptional activation; however, the underlying mechanisms are not well defined. Here, we show that the H3K36me2 chromatin mark written by the ASH1L histone methyltransferase is preferentially bound in vivo by LEDGF, a mixed-lineage leukemia (MLL)-associated protein that colocalizes with MLL, ASH1L, and H3K36me2 on chromatin genome wide. Furthermore, ASH1L facilitates recruitment of LEDGF and wild-type MLL proteins to chromatin at key leukemia target genes and is a crucial regulator of MLL-dependent transcription and leukemic transformation. Conversely, KDM2A, an H3K36me2 demethylase and Polycomb group silencing protein, antagonizes MLL-associated leukemogenesis. Our studies are the first to provide a basic mechanistic insight into epigenetic interactions wherein placement, interpretation, and removal of H3K36me2 contribute to the regulation of gene expression and MLL leukemia, and suggest ASH1L as a novel target for therapeutic intervention. SIGNIFICANCE: Epigenetic regulators play vital roles in cancer pathogenesis and represent a new frontier in therapeutic targeting. Our studies provide basic mechanistic insight into the role of H3K36me2 in transcription activation and MLL leukemia pathogenesis and implicate ASH1L histone methyltransferase as a promising target for novel molecular therapy. Cancer Discov; 6(7); 770-83. ©2016 AACR.See related commentary by Balbach and Orkin, p. 700This article is highlighted in the In This Issue feature, p. 681.
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Proteínas de Unión al ADN/metabolismo , Histonas/metabolismo , Leucemia/genética , Leucemia/metabolismo , Lisina/metabolismo , Proteína de la Leucemia Mieloide-Linfoide/metabolismo , Factores de Transcripción/metabolismo , Animales , Línea Celular , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Inmunoprecipitación de Cromatina , Modelos Animales de Enfermedad , Proteínas F-Box/metabolismo , Femenino , Regulación Leucémica de la Expresión Génica , Xenoinjertos , Secuenciación de Nucleótidos de Alto Rendimiento , Histona Metiltransferasas , N-Metiltransferasa de Histona-Lisina/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Histona Demetilasas con Dominio de Jumonji/metabolismo , Leucemia/patología , Metilación , Ratones , Proteína de la Leucemia Mieloide-Linfoide/genética , Nucleosomas/metabolismo , Regiones Promotoras Genéticas , Unión ProteicaRESUMEN
p53 and p63 share extensive sequence and structure homology. p53 is frequently mutated in cancer, whereas mutations in p63 cause developmental disorders manifested in ectodermal dysplasia, limb defects, and orofacial clefting. We have established primary adult skin keratinocytes from ectrodactyly, ectodermal dysplasia, and cleft lip/palate (EEC) syndrome patients with p63 mutations as an in vitro human model to study the disease mechanism in the skin of EEC patients. We show that these patient keratinocytes cultured either in submerged 2D cultures or in 3D skin equivalents have impaired epidermal differentiation and stratification. Treatment of these patient keratinocytes with the mutant p53-targeting compound APR-246/PRIMA-1(MET) (p53 reactivation and induction of massive apoptosis) that has been successfully tested in a phase I/II clinical trial in cancer patients partially but consistently rescued morphological features and gene expression during epidermal stratification in both 2D and 3D models. This rescue coincides with restoration of p63 target-gene expression. Our data show that EEC patient keratinocytes with p63 mutations can be used for characterization of the abnormal molecular circuitry in patient skin and may open possibilities for the design of novel pharmacological treatment strategies for patients with mutant p63-associated developmental abnormalities.
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Labio Leporino/tratamiento farmacológico , Labio Leporino/patología , Fisura del Paladar/tratamiento farmacológico , Fisura del Paladar/patología , Displasia Ectodérmica/tratamiento farmacológico , Displasia Ectodérmica/patología , Queratinocitos/efectos de los fármacos , Queratinocitos/patología , Mutación , Quinuclidinas/farmacología , Factores de Transcripción/genética , Proteínas Supresoras de Tumor/genética , Adulto , Secuencia de Bases , Sitios de Unión/genética , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/genética , Células Cultivadas , Labio Leporino/genética , Labio Leporino/metabolismo , Fisura del Paladar/genética , Fisura del Paladar/metabolismo , Displasia Ectodérmica/genética , Displasia Ectodérmica/metabolismo , Epidermis/efectos de los fármacos , Epidermis/metabolismo , Epidermis/patología , Femenino , Humanos , Queratinocitos/metabolismo , Masculino , Persona de Mediana Edad , Modelos Biológicos , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Transcripción/química , Factores de Transcripción/metabolismo , Transcripción Genética/efectos de los fármacos , Proteínas Supresoras de Tumor/química , Proteínas Supresoras de Tumor/metabolismoRESUMEN
Reactivation of mutant p53 in human tumor cells should induce cell death by apoptosis and thus eliminate the tumor. Several small molecules that reactivate mutant p53 have been identified. Here we show that STIMA-1, a low molecular weight compound with some structural similarities to the previously identified molecule CP-31398, can stimulate mutant p53 DNA binding in vitro and induce expression of p53 target proteins and trigger apoptosis in mutant p53-expressing human tumor cells. Human diploid fibroblasts are significantly more resistant to STIMA-1 than mutant or wild type p53-carrying tumor cells. STIMA-1 may provide new insights into possible mechanisms of mutant p53 reactivation and thus facilitate the development of novel anticancer drugs that target mutant p53-carrying tumors.