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1.
Mol Cell ; 84(9): 1742-1752.e5, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38513661

RESUMEN

Histone H3 lysine 4 mono-methylation (H3K4me1) marks poised or active enhancers. KMT2C (MLL3) and KMT2D (MLL4) catalyze H3K4me1, but their histone methyltransferase activities are largely dispensable for transcription during early embryogenesis in mammals. To better understand the role of H3K4me1 in enhancer function, we analyze dynamic enhancer-promoter (E-P) interactions and gene expression during neural differentiation of the mouse embryonic stem cells. We found that KMT2C/D catalytic activities were only required for H3K4me1 and E-P contacts at a subset of candidate enhancers, induced upon neural differentiation. By contrast, a majority of enhancers retained H3K4me1 in KMT2C/D catalytic mutant cells. Surprisingly, H3K4me1 signals at these KMT2C/D-independent sites were reduced after acute depletion of KMT2B, resulting in aggravated transcriptional defects. Our observations therefore implicate KMT2B in the catalysis of H3K4me1 at enhancers and provide additional support for an active role of H3K4me1 in enhancer-promoter interactions and transcription in mammalian cells.


Asunto(s)
Diferenciación Celular , Elementos de Facilitación Genéticos , N-Metiltransferasa de Histona-Lisina , Histonas , Lisina/análogos & derivados , Células Madre Embrionarias de Ratones , Regiones Promotoras Genéticas , Animales , Ratones , Histonas/metabolismo , Histonas/genética , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Células Madre Embrionarias de Ratones/metabolismo , Células Madre Embrionarias de Ratones/citología , Activación Transcripcional , Metilación , Regulación del Desarrollo de la Expresión Génica , Proteína de la Leucemia Mieloide-Linfoide/metabolismo , Proteína de la Leucemia Mieloide-Linfoide/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética
2.
Cell ; 153(5): 1134-48, 2013 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-23664764

RESUMEN

Epigenetic mechanisms have been proposed to play crucial roles in mammalian development, but their precise functions are only partially understood. To investigate epigenetic regulation of embryonic development, we differentiated human embryonic stem cells into mesendoderm, neural progenitor cells, trophoblast-like cells, and mesenchymal stem cells and systematically characterized DNA methylation, chromatin modifications, and the transcriptome in each lineage. We found that promoters that are active in early developmental stages tend to be CG rich and mainly engage H3K27me3 upon silencing in nonexpressing lineages. By contrast, promoters for genes expressed preferentially at later stages are often CG poor and primarily employ DNA methylation upon repression. Interestingly, the early developmental regulatory genes are often located in large genomic domains that are generally devoid of DNA methylation in most lineages, which we termed DNA methylation valleys (DMVs). Our results suggest that distinct epigenetic mechanisms regulate early and late stages of ES cell differentiation.


Asunto(s)
Metilación de ADN , Células Madre Embrionarias/metabolismo , Epigenómica , Regulación del Desarrollo de la Expresión Génica , Animales , Diferenciación Celular , Cromatina/metabolismo , Islas de CpG , Células Madre Embrionarias/citología , Histonas/metabolismo , Humanos , Metilación , Neoplasias/genética , Regiones Promotoras Genéticas , Pez Cebra/embriología
3.
Mol Cell ; 76(3): 453-472.e8, 2019 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-31519520

RESUMEN

MYOD-directed fibroblast trans-differentiation into skeletal muscle provides a unique model to investigate how one transcription factor (TF) reconfigures the three-dimensional chromatin architecture to control gene expression, which is otherwise achieved by the combinatorial activities of multiple TFs. Integrative analysis of genome-wide high-resolution chromatin interactions, MYOD and CTCF DNA-binding profile, and gene expression, revealed that MYOD directs extensive re-wiring of interactions involving cis-regulatory and structural genomic elements, including promoters, enhancers, and insulated neighborhoods (INs). Re-configured INs were hot-spots of differential interactions, whereby MYOD binding to highly constrained sequences at IN boundaries and/or inside INs led to alterations of promoter-enhancer interactions to repress cell-of-origin genes and to activate muscle-specific genes. Functional evidence shows that MYOD-directed re-configuration of chromatin interactions temporally preceded the effect on gene expression and was mediated by direct MYOD-DNA binding. These data illustrate a model whereby a single TF alters multi-loop hubs to drive somatic cell trans-differentiation.


Asunto(s)
Transdiferenciación Celular , Reprogramación Celular , Ensamble y Desensamble de Cromatina , Cromatina/metabolismo , Fibroblastos/metabolismo , Desarrollo de Músculos , Proteína MioD/metabolismo , Mioblastos Esqueléticos/metabolismo , Animales , Sitios de Unión , Línea Celular , Transdiferenciación Celular/genética , Cromatina/genética , Femenino , Regulación del Desarrollo de la Expresión Génica , Humanos , Ratones , Desarrollo de Músculos/genética , Proteína MioD/genética , Conformación de Ácido Nucleico , Fenotipo , Unión Proteica , Relación Estructura-Actividad , Transcripción Genética
4.
Cell ; 146(6): 1016-28, 2011 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-21925322

RESUMEN

We report the identification of 67 previously undescribed histone modifications, increasing the current number of known histone marks by about 70%. We further investigated one of the marks, lysine crotonylation (Kcr), confirming that it represents an evolutionarily-conserved histone posttranslational modification. The unique structure and genomic localization of histone Kcr suggest that it is mechanistically and functionally different from histone lysine acetylation (Kac). Specifically, in both human somatic and mouse male germ cell genomes, histone Kcr marks either active promoters or potential enhancers. In male germinal cells immediately following meiosis, Kcr is enriched on sex chromosomes and specifically marks testis-specific genes, including a significant proportion of X-linked genes that escape sex chromosome inactivation in haploid cells. These results therefore dramatically extend the repertoire of histone PTM sites and designate Kcr as a specific mark of active sex chromosome-linked genes in postmeiotic male germ cells.


Asunto(s)
Regulación de la Expresión Génica , Código de Histonas , Animales , Células HeLa , Histonas/química , Histonas/metabolismo , Humanos , Lisina/metabolismo , Masculino , Meiosis , Ratones , Procesamiento Proteico-Postraduccional , Testículo/citología , Testículo/metabolismo
5.
Proc Natl Acad Sci U S A ; 120(20): e2210991120, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37155843

RESUMEN

In 2021, the World Health Organization reclassified glioblastoma, the most common form of adult brain cancer, into isocitrate dehydrogenase (IDH)-wild-type glioblastomas and grade IV IDH mutant (G4 IDHm) astrocytomas. For both tumor types, intratumoral heterogeneity is a key contributor to therapeutic failure. To better define this heterogeneity, genome-wide chromatin accessibility and transcription profiles of clinical samples of glioblastomas and G4 IDHm astrocytomas were analyzed at single-cell resolution. These profiles afforded resolution of intratumoral genetic heterogeneity, including delineation of cell-to-cell variations in distinct cell states, focal gene amplifications, as well as extrachromosomal circular DNAs. Despite differences in IDH mutation status and significant intratumoral heterogeneity, the profiled tumor cells shared a common chromatin structure defined by open regions enriched for nuclear factor 1 transcription factors (NFIA and NFIB). Silencing of NFIA or NFIB suppressed in vitro and in vivo growths of patient-derived glioblastomas and G4 IDHm astrocytoma models. These findings suggest that despite distinct genotypes and cell states, glioblastoma/G4 astrocytoma cells share dependency on core transcriptional programs, yielding an attractive platform for addressing therapeutic challenges associated with intratumoral heterogeneity.


Asunto(s)
Astrocitoma , Neoplasias Encefálicas , Glioblastoma , Adulto , Humanos , Glioblastoma/genética , Glioblastoma/patología , Cromatina/genética , Transcriptoma , Astrocitoma/genética , Astrocitoma/patología , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Mutación , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/metabolismo
6.
Nature ; 574(7779): 575-580, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31645732

RESUMEN

The Warburg effect, which originally described increased production of lactate in cancer, is associated with diverse cellular processes such as angiogenesis, hypoxia, polarization of macrophages and activation of T cells. This phenomenon is intimately linked to several diseases including neoplasia, sepsis and autoimmune diseases1,2. Lactate, which is converted from pyruvate in tumour cells, is widely known as an energy source and metabolic by-product. However, its non-metabolic functions in physiology and disease remain unknown. Here we show that lactate-derived lactylation of histone lysine residues serves as an epigenetic modification that directly stimulates gene transcription from chromatin. We identify 28 lactylation sites on core histones in human and mouse cells. Hypoxia and bacterial challenges induce the production of lactate by glycolysis, and this acts as a precursor that stimulates histone lactylation. Using M1 macrophages that have been exposed to bacteria as a model system, we show that histone lactylation has different temporal dynamics from acetylation. In the late phase of M1 macrophage polarization, increased histone lactylation induces homeostatic genes that are involved in wound healing, including Arg1. Collectively, our results suggest that an endogenous 'lactate clock' in bacterially challenged M1 macrophages turns on gene expression to promote homeostasis. Histone lactylation thus represents an opportunity to improve our understanding of the functions of lactate and its role in diverse pathophysiological conditions, including infection and cancer.


Asunto(s)
Epigénesis Genética , Glucólisis/genética , Histonas/química , Histonas/metabolismo , Ácido Láctico/metabolismo , Acetilación , Secuencia de Aminoácidos , Animales , Línea Celular Tumoral , Cromatina/química , Cromatina/genética , Cromatina/metabolismo , Homeostasis , Humanos , Hipoxia/metabolismo , Lisina/química , Lisina/metabolismo , Macrófagos/metabolismo , Macrófagos/microbiología , Masculino , Ratones , Ratones Endogámicos C57BL , Reproducibilidad de los Resultados , Transcripción Genética
7.
Nature ; 575(7784): 699-703, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31748743

RESUMEN

Oncogenes are commonly amplified on particles of extrachromosomal DNA (ecDNA) in cancer1,2, but our understanding of the structure of ecDNA and its effect on gene regulation is limited. Here, by integrating ultrastructural imaging, long-range optical mapping and computational analysis of whole-genome sequencing, we demonstrate the structure of circular ecDNA. Pan-cancer analyses reveal that oncogenes encoded on ecDNA are among the most highly expressed genes in the transcriptome of the tumours, linking increased copy number with high transcription levels. Quantitative assessment of the chromatin state reveals that although ecDNA is packaged into chromatin with intact domain structure, it lacks higher-order compaction that is typical of chromosomes and displays significantly enhanced chromatin accessibility. Furthermore, ecDNA is shown to have a significantly greater number of ultra-long-range interactions with active chromatin, which provides insight into how the structure of circular ecDNA affects oncogene function, and connects ecDNA biology with modern cancer genomics and epigenetics.


Asunto(s)
Cromatina/genética , ADN Circular/metabolismo , Regulación Neoplásica de la Expresión Génica/genética , Neoplasias/genética , Oncogenes/genética , Línea Celular Tumoral , Cromatina/química , ADN Circular/genética , Humanos , Microscopía Electrónica de Rastreo , Neoplasias/fisiopatología
8.
Cell Mol Life Sci ; 81(1): 92, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38363375

RESUMEN

The maintenance of genome integrity in the germline is crucial for mammalian development. Long interspersed element type 1 (LINE-1, L1) is a mobile genetic element that makes up about 17% of the human genome and poses a threat to genome integrity. N6-methyl-adenosine (m6A) plays an essential role in regulating various biological processes. However, the function of m6A modification in L1 retrotransposons and human germline development remains largely unknown. Here we knocked out the m6A methyltransferase METTL3 or the m6A reader YTHDF2 in human embryonic stem cells (hESCs) and discovered that METTL3 and YTHDF2 are crucial for inducing human spermatogonial stem cells (hSSCs) from hESCs in vitro. The removal of METTL3 or YTHDF2 resulted in increased L1 retrotransposition and reduced the efficiency of SSC differentiation in vitro. Further analysis showed that YTHDF2 recognizes the METTL3-catalyzed m6A modification of L1 retrotransposons and degrades L1 mRNA through autophagy, thereby blocking L1 retrotransposition. Moreover, the study confirmed that m6A modification in human fetal germ cells promotes the degradation of L1 retrotransposon RNA, preventing the insertion of new L1 retrotransposons into the genome. Interestingly, L1 retrotransposon RNA was highly expressed while METTL3 was significantly downregulated in the seminal plasma of azoospermic patients with meiotic arrest compared to males with normal fertility. Additionally, we identified some potentially pathogenic variants in m6A-related genes in azoospermic men with meiotic arrest. In summary, our study suggests that m6A modification serves as a guardian of genome stability during human germline development and provides novel insights into the function and regulatory mechanisms of m6A modification in restricting L1 retrotransposition.


Asunto(s)
Azoospermia , Retroelementos , Masculino , Animales , Humanos , Retroelementos/genética , ARN , Azoospermia/genética , Diferenciación Celular/genética , Metiltransferasas/genética , Metiltransferasas/metabolismo , ARN Mensajero/genética , Mamíferos/metabolismo
9.
Mol Phylogenet Evol ; 195: 108062, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38485104

RESUMEN

Palaeogeological events and climate oscillations profoundly impact the demographics and distributions of small-range species, increasing the extinction risk. The largest water strider worldwide, Gigantometra gigas (Hemiptera: Gerridae), exhibits restricted distributions in Vietnam and southern China. Herein, we generated three genomic datasets (mitogenomes, 146 nuclear protein-coding genes and single nucleotide polymorphisms) with ecological niche modelling (ENM) to explicitly test whether the present-day distribution of G. gigas actually resulted from geographical and climatic effects. We found that the origin of this largest water strider reached the divergence time of the genus within Gerridae, providing a greater opportunity to explore its response to geographic movements. The right-lateral motion of the Red River Fault facilitated the divergence of two phylogeographic lineages, resulting in the "north-south component" genetic pattern in G. gigas. The Hainan and southeast Vietnam populations of the southern linage were completely separated by the Beibu Gulf but exhibited similar genetic compositions, confirming that Hainan had a continental origin and that Hainan Island joined with the Indo-China Peninsula to promote gene exchange among populations. Additionally, we noticed the low genetic diversity but long demographic history of the northern lineage, which displayed population dynamics opposite to those of other organisms. Integrating the demographic changes and ENM findings revealed that suitable habitat contraction and rapid demographic decline during the Last Glacial Maximum (LGM) triggered the low genetic diversity of the northern lineage. Overall, the demographic history of the largest water strider was mainly shaped by geographical features, and first provided evidence from the phylogeographic perspective of aquatic insects to support the hypothesis of Hainan Island shifting.


Asunto(s)
Ríos , Agua , Filogeografía , Filogenia , China , Variación Genética , ADN Mitocondrial/genética
10.
Mol Phylogenet Evol ; 195: 108055, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38485106

RESUMEN

Comparative phylogeographic studies of closely related species sharing co-distribution areas can elucidate the role of shared historical factors and environmental changes in shaping their phylogeographic pattern. The bean bugs, Riptortus pedestris and Riptortus linearis, which both inhabit subtropical regions in East Asia, are recognized as highly destructive soybean pests. Many previous studies have investigated the biological characteristics, pheromones, chemicals and control mechanisms of these two pests, but few studies have explored their phylogeographic patterns and underlying factors. In this study, we generated a double-digest restriction site-associated DNA sequencing (ddRAD-seq) dataset to investigate phylogeographic patterns and construct ecological niche models (ENM) for both Riptortus species. Our findings revealed similar niche occupancies and population genetic structures between the two species, with each comprising two phylogeographic lineages (i.e., the mainland China and the Indochina Peninsula clades) that diverged approximately 0.1 and 0.3 million years ago, respectively. This divergence likely resulted from the combined effects of temperatures variation and geographical barriers in the mountainous regions of Southwest China. Further demographic history and ENM analyses suggested that both pests underwent rapid expansion prior to the Last Glacial Maximum (LGM). Furthermore, ENM predicts a northward shift of both pests into new soybean-producing regions due to global warming. Our study indicated that co-distribution soybean pests with overlapping ecological niches and similar life histories in subtropical regions of East Asia exhibit congruent phylogeographic and demographic patterns in response to shared historical biogeographic drivers.


Asunto(s)
Glycine max , Heterópteros , Animales , Glycine max/genética , Filogenia , Variación Genética , Evolución Molecular , ADN Mitocondrial/genética , Filogeografía , Asia Oriental , Heterópteros/genética
11.
Mol Phylogenet Evol ; 198: 108121, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38851309

RESUMEN

The subgenus Aeschyntelus includes six species that show variations in body color and shape, thus making it difficult to identify them based on morphological identification alone. To date, no genetic study has evaluated species within this genus. Herein, we collected 171 individuals from 90 localities of Rhopalus and employed an integrative taxonomic approach that incorporated morphological data, mitochondrial genomic data (COI, whole mitochondrial data) and nuclear genomic data (18S + 28S rRNAs, nuclear genome-wide SNPs) to delineate species boundaries. Our analyses confirmed the status of nine described species of Rhopalus and proposed the recognition of one new species known as Rhopalus qinlinganus sp. nov., which is classified within the subgenus Aeschyntelus. Discrepancies arising from nuclear and mitochondrial data suggest the presence of mito-nuclear discordance. Specifically, mitochondrial data indicated admixture within Clade A, comprising R. kerzhneri and R. latus, whereas genome-wide SNPs unambiguously identified two separate species, aligning with morphological classification. Conversely, mitochondrial data clearly distinguished Clade B- consisting of R. sapporensis into two lineages, whereas genome-wide SNPs unequivocally identified a single species. Our study also provides insights into the evolutionary history of Aeschyntelus, thus indicating that it likely originated in East Asia during the middle Miocene. The development of Aeschyntelus biodiversity in the southwestern mountains of China occurred via an uplift-driven diversification process. Our findings highlight the necessity of integrating both morphological and multiple molecular datasets for precise species identification, particularly when delineating closely related species. Additionally, it reveals the important role of mountain orogenesis on speciation within the southwestern mountains of China.


Asunto(s)
Heterópteros , Filogenia , Filogeografía , Animales , Heterópteros/genética , Heterópteros/clasificación , Heterópteros/anatomía & histología , ADN Mitocondrial/genética , Núcleo Celular/genética , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN , China
12.
Mol Phylogenet Evol ; 195: 108056, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38493987

RESUMEN

The yellow spotted stink bug (YSSB), Erthesina fullo (Thunberg, 1783) is an important Asian pest that has recently successfully invaded Europe and an excellent material for research on the initial stage of biological invasion. Here, we reported the native evolutionary history, recent invasion history, and potential invasion threats of YSSB for the first time based on population genetic methods [using double digest restriction-site associated DNA (ddRAD) data and mitochondrial COI and CYTB] and ecological niche modelling. The results showed that four lineages (east, west, southwest, and Hainan Island) were established in the native range with a strong east-west differentiation phylogeographical structure, and the violent climate fluctuation might cause population divergence during the Middle and Upper Pleistocene. In addition, land bridges and monsoon promote dispersal and directional genetic exchanging between island populations and neighboring continental populations. The east lineage (EA) was identified as the source of invasion in Albania. EA had the widest geographical distribution among all other lineages, with a star-like haplotype network with the main haplotype as the core. It also had a rapid population expansion history, indicating that the source lineage might have stronger diffusion ability and adaptability. Our findings provided a significant biological basis for fine tracking of invasive source at the lineage or population level and promote early invasion warning of potential invasive species on a much subtler lineage level.


Asunto(s)
Heterópteros , Animales , Filogeografía , Filogenia , Heterópteros/genética , Evolución Biológica , Mitocondrias/genética , ADN Mitocondrial/genética , Variación Genética
13.
Cardiovasc Diabetol ; 23(1): 58, 2024 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-38336692

RESUMEN

AIM: Patients with diabetes mellitus have poor prognosis after myocardial ischemic injury. However, the mechanism is unclear and there are no related therapies. We aimed to identify regulators of diabetic myocardial ischemic injury. METHODS AND RESULTS: Mass spectrometry-based, non-targeted metabolomic approach was used to profile coronary sinus blood from diabetic and non-diabetic Bama-mini pigs at 0.5-h post coronary artery ligation. Six metabolites had a |log2 (Fold Change)|> 1.3. Among them, the most changed is arachidonic acid (AA), levels of which were 32 times lower in diabetic pigs than in non-diabetic pigs. The AA-derived products, PGI2 and 6-keto-PGF1α, were also significantly reduced. AA treatment of cultured cardiomyocytes protected against cell death by 30% at 48 h of high glucose and oxygen deprivation, which coincided with increased mitophagic activity (as indicated by increased LC3II/LC3I, decreased p62 and increased parkin & PINK1), improved mitochondrial renewal (upregulation of Drp1 and FIS1), reduced ROS generation and increased ATP production. These cardioprotective effects were abolished by PINK1(a crucial mitophagy protein) knockdown or the autophagy inhibitor 3-Methyladenine. The protective effect of AA was also inhibited by indomethacin and Cay10441, a prostacyclin receptor antagonist. Furthermore, diabetic Sprague Dawley rats were subjected to coronary ligation for 40 min and AA treatment (10 mg/day per animal gavaged) decreased myocardial infarct size, cell apoptosis index, inflammatory cytokines and improved heart function. Scanning electron microscopy showed more intact mitochondria in the border zone of infarcted myocardium in AA treated rats. Lastly, diabetic patients after myocardial infarction had lower plasma levels of AA and 6-keto-PGF1α and reduced cardiac ejection fraction, compared with non-diabetic patients after myocardial infarction. Plasma AA level was inversely correlated with fasting blood glucose. CONCLUSIONS: AA protects against diabetic ischemic myocardial damage by promoting mitochondrial autophagy and renewal, which is related to AA derived PGI2 signaling. AA may represent a new strategy to treat diabetic myocardial ischemic injury.


Asunto(s)
Diabetes Mellitus , Infarto del Miocardio , Humanos , Ratas , Animales , Porcinos , Ratas Sprague-Dawley , Ácido Araquidónico/farmacología , Porcinos Enanos/metabolismo , Infarto del Miocardio/metabolismo , Proteínas Quinasas/metabolismo , Apoptosis
14.
Diabetes Obes Metab ; 26(6): 2176-2187, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38419419

RESUMEN

AIMS: To assess the excess risk of cardiovascular disease (CVD) associated with different criteria for metabolic health, and the interplay of body size, insulin sensitivity and metabolic health with CVD risk. MATERIALS AND METHODS: We conducted a prospective study involving 115 638 participants from the China Cardiometabolic Disease and Cancer Cohort (4C) Study. Metabolic health was defined using three different definitions: (1) insulin sensitivity defined by homeostatic model assessment of insulin resistance index; (2) absence of metabolic syndrome according to the National Cholesterol Education Program Adult Treatment Panel III criteria; and (3) simultaneous absence of metabolic abnormalities (diabetes, hypertension, dyslipidaemia). The primary endpoint was a composite of incident CVD events comprising the first occurrence of myocardial infarction, stroke, heart failure, or cardiovascular death. RESULTS: During a mean 3.61-year follow-up period, obese individuals with insulin sensitivity (multivariable-adjusted hazard ratio [HR] 1.69, 95% confidence interval [CI] 1.37-2.08), or without metabolic syndrome (HR 1.46, 95% CI 1.13-1.89) still exhibited increased CVD risks, when compared to their normal-weight counterparts. Otherwise, those with obesity but simultaneous absence of metabolic abnormalities demonstrated similar CVD risk compared to normal-weight individuals (HR 0.91, 95% CI 0.53-1.59). CVD risk increased with the number of abnormalities across body mass index categories, regardless of insulin sensitivity. CONCLUSIONS: This study emphasizes the need for refined definitions of metabolic health and advocates for meticulous screening for metabolic abnormalities to reduce cardiovascular risks, even in individuals with normal weight and insulin sensitivity.


Asunto(s)
Tamaño Corporal , Enfermedades Cardiovasculares , Resistencia a la Insulina , Síndrome Metabólico , Obesidad , Humanos , Masculino , Femenino , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , China/epidemiología , Persona de Mediana Edad , Estudios Prospectivos , Adulto , Síndrome Metabólico/epidemiología , Síndrome Metabólico/complicaciones , Obesidad/complicaciones , Obesidad/epidemiología , Factores de Riesgo , Anciano , Neoplasias/epidemiología , Estudios de Cohortes , Estudios de Seguimiento , Pueblos del Este de Asia
15.
Pharm Res ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918308

RESUMEN

PURPOSE: Joint destruction is a major burden and an unsolved problem in rheumatoid arthritis (RA) patients. We designed an intra-articular mesoporous silica nanosystem (MSN-TP@PDA-GlcN) with anti-inflammatory and joint protection effects. The nanosystem was synthesized by encapsulating triptolide (TP) in mesoporous silica nanoparticles and coating it with pH-sensitive polydopamine (PDA) and glucosamine (GlcN) grafting on the PDA. The nano-drug delivery system with anti-inflammatory and joint protection effects should have good potency against RA. METHODS: A template method was used to synthesize mesoporous silica (MSN). MSN-TP@PDA-GlcN was synthesized via MSN loading with TP, coating with PDA and grafting of GlcN on PDA. The drug release behavior was tested. A cellular inflammatory model and a rat RA model were used to evaluate the effects on RA. In vivo imaging and microdialysis (MD) system were used to analyze the sustained release and pharmacokinetics in RA rats. RESULTS: TMSN-TP@PDA-GlcN was stable, had good biocompatibility, and exhibited sustained release of drugs in acidic environments. It had excellent anti-inflammatory effects in vitro and in vivo. It also effectively repaired joint destruction in vivo without causing any tissue toxicity. In vivo imaging and pharmacokinetics experiments showed that the nanosystem prolonged the residence time, lowered the Cmax value and enhanced the relative bioavailability of TP. CONCLUSIONS: These results demonstrated that MSN-TP@PDA-GlcN sustained the release of drugs in inflammatory joints and produced effective anti-inflammatory and joint protection effects on RA. This study provides a new strategy for the treatment of RA.

16.
Nature ; 560(7720): 655-660, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30135582

RESUMEN

Mammalian cells are surrounded by neighbouring cells and extracellular matrix (ECM), which provide cells with structural support and mechanical cues that influence diverse biological processes1. The Hippo pathway effectors YAP (also known as YAP1) and TAZ (also known as WWTR1) are regulated by mechanical cues and mediate cellular responses to ECM stiffness2,3. Here we identified the Ras-related GTPase RAP2 as a key intracellular signal transducer that relays ECM rigidity signals to control mechanosensitive cellular activities through YAP and TAZ. RAP2 is activated by low ECM stiffness, and deletion of RAP2 blocks the regulation of YAP and TAZ by stiffness signals and promotes aberrant cell growth. Mechanistically, matrix stiffness acts through phospholipase Cγ1 (PLCγ1) to influence levels of phosphatidylinositol 4,5-bisphosphate and phosphatidic acid, which activates RAP2 through PDZGEF1 and PDZGEF2 (also known as RAPGEF2 and RAPGEF6). At low stiffness, active RAP2 binds to and stimulates MAP4K4, MAP4K6, MAP4K7 and ARHGAP29, resulting in activation of LATS1 and LATS2 and inhibition of YAP and TAZ. RAP2, YAP and TAZ have pivotal roles in mechanoregulated transcription, as deletion of YAP and TAZ abolishes the ECM stiffness-responsive transcriptome. Our findings show that RAP2 is a molecular switch in mechanotransduction, thereby defining a mechanosignalling pathway from ECM stiffness to the nucleus.


Asunto(s)
Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Proteínas de Unión al GTP rap/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Transformación Celular Neoplásica , Matriz Extracelular/química , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Femenino , Proteínas Activadoras de GTPasa/metabolismo , Quinasas del Centro Germinal , Factores de Intercambio de Guanina Nucleótido/metabolismo , Células HEK293 , Vía de Señalización Hippo , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Ratones , Ratones Endogámicos NOD , Ratones Desnudos , Ratones SCID , Proteínas del Tejido Nervioso/metabolismo , Fosfolipasa C gamma/metabolismo , Fosfoproteínas/metabolismo , Transactivadores , Factores de Transcripción , Proteínas Coactivadoras Transcripcionales con Motivo de Unión a PDZ , Transcriptoma , Proteínas Señalizadoras YAP , Proteínas de Unión al GTP rap/genética
17.
Surg Endosc ; 38(4): 1791-1806, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38291159

RESUMEN

BACKGROUND: Currently, there is no clear consensus on whether medical treatment or endoscopic treatment should be used for peptic ulcer bleeding patients with adherent clot. The aim of this study is to investigate the hemostatic effects of medical treatment, single endoscopic treatment, and combination endoscopic treatment for peptic ulcer bleeding (PUB) patients with adherent clot. METHODS: We retrospectively analyzed PUB patients with adherent clot who underwent endoscopic examination or treatment in our center from March 2014 to January 2023 and received intravenous administration of proton pump inhibitors. Patients were divided into medical treatment (MT) group, single endoscopic treatment (ST) group, and combined endoscopic treatment (CT) group. Subsequently, inverse probability of treatment weighting (IPTW) was performed to calculate the rebleeding rate. RESULTS: A total of 605 eligible patients were included in this study. After IPTW, the rebleeding rate in the MT group on days 3, 7, 14, and 30 were 13.3 (7.3), 14.2 (7.8), 14.5 (7.9), and 14.5 (7.9), respectively; the rebleeding rates in the ST group were 17.4 (5.1), 20.8 (6.1), 20.8 (6.1), and 20.8 (6.1), respectively; the rebleeding rates in the CT group were 0.4 (0.9), 1.7 (3.3), 2.3 (4.5), and 2.3 (4.5), respectively. Although the rebleeding rate in the medical treatment group was higher, there was no significant difference among the three groups on days 3, 7, 14, and 30 (P = 0.132, 0.442, 0.552, and 0.552). CONCLUSIONS: Medical therapy has similar hemostatic efficacy with endoscopic treatment for PUB patients with adherent clot (FIIb ulcers). However, for patients with more risk factors and access to well-equipped endoscopy centers, endoscopic treatment may be considered. The choice of treatment approach should be based on the individual conditions of the patient, as well as other factors such as medical resources available.


Asunto(s)
Hemostasis Endoscópica , Hemostáticos , Úlcera Péptica , Humanos , Úlcera/complicaciones , Úlcera/terapia , Estudios Retrospectivos , Úlcera Péptica Hemorrágica/etiología , Endoscopía Gastrointestinal/efectos adversos , Hemostasis Endoscópica/efectos adversos , Úlcera Péptica/complicaciones , Recurrencia
18.
Artículo en Inglés | MEDLINE | ID: mdl-38836725

RESUMEN

Background: Peritoneal lesions present diagnostic challenges, necessitating precise imaging techniques. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) offers a promising approach for accurate diagnosis, aiding in optimal patient management and treatment planning. Objective: This study aims to assess the diagnostic efficacy of EUS-FNA in peritoneal lesions to offer insight in guiding optimal patient management. Methods: A prospective observational study was conducted, and a total of 58 patients who underwent EUS-FNA of the peritoneum at our hospital between October 2021 and November 2021 were included. The ultrasound diagnostic instrument facilitated puncture guidance, with 2-5 punctures performed in various parts of the selected peritoneal lesion areas. The analysis encompassed evaluating the sensitivity, specificity, positive predictive value, and negative predictive value of biopsy for diagnosing peritoneal-associated lesions, alongside assessing the number of punctures, puncture satisfaction, and incidence of postoperative complications. Results: The included patients undergoing EUS-FNA revealed that 41 (70.69%) had malignant lesions, while 17 (29.31%) presented with benign lesions. The diagnostic accuracy of EUS-FNA for peritoneal lesions was determined to be 94.83%, with a diagnostic sensitivity of 97.30% for malignant tumors, specificity of 90.48%, positive predictive value of 94.74%, and negative predictive value of 95%. Lesions exhibited a size range of 2.5cm × 2.9cm to 15.2cm × 9.8cm. Each patient underwent 2-5 punctures (3.3 ± 1.4), with a puncture satisfaction rate of 96.55%. The incidence of postoperative complications following EUS-FNA was found to be 3.45%. Conclusion: EUS-FNA exhibits substantial diagnostic utility for peritoneal-related lesions, marked by exceptional accuracy, sensitivity, specificity, and favorable safety. Its clinical adoption is warranted, promising improved patient care and management.

19.
BMC Med Educ ; 24(1): 461, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38671399

RESUMEN

BACKGROUND: 3D visualization technology applies computers and other devices to create a realistic virtual world for individuals with various sensory experiences such as 3D vision, touch, and smell to gain a more effective understanding of the relationships between real spatial structures and organizations. The purpose of this study was to comprehensively evaluate the effectiveness of 3D visualization technology in human anatomy teaching/training and explore the potential factors that affect the training effects to better guide the teaching of classroom/laboratory anatomy. METHODS: We conducted a meta-analysis of randomized controlled studies on teaching human anatomy using 3D visualization technology. We extensively searched three authoritative databases, PubMed, Web of Science, and Embase; the main outcomes were the participants' test scores and satisfaction, while the secondary outcomes were time consumption and enjoyment. Heterogeneity by I² was statistically determined because I²> 50%; therefore, a random-effects model was employed, using data processing software such as RevMan, Stata, and VOSviewer to process data, apply standardized mean difference and 95% confidence interval, and subgroup analysis to evaluate test results, and then conduct research through sensitivity analysis and meta-regression analysis. RESULTS: Thirty-nine randomized controlled trials (2,959 participants) were screened and included in this study. The system analysis of the main results showed that compared with other methods, including data from all regions 3D visualization technology moderately improved test scores as well as satisfaction and enjoyment; however, the time that students took to complete the test was not significantly reduced. Meta-regression analysis also showed that regional factorsaffected test scores, whereas other factors had no significant impact. When the literature from China was excluded, the satisfaction and happiness of the 3D virtual-reality group were statistically significant compared to those of the traditional group; however, the test results and time consumption were not statistically significant. CONCLUSION: 3D visualization technology is an effective way to improve learners' satisfaction with and enjoyment of human anatomical learning, but it cannot reduce the time required for testers to complete the test. 3D visualization technology may struggle to improve the testers' scores. The literature test results from China are more prone to positive results and affected by regional bias.


Asunto(s)
Anatomía , Imagenología Tridimensional , Estudiantes de Medicina , Humanos , Anatomía/educación , Estudiantes de Medicina/psicología , Internado y Residencia , Ensayos Clínicos Controlados Aleatorios como Asunto , Realidad Virtual , Análisis de Regresión , Instrucción por Computador/métodos
20.
Mol Biol Evol ; 39(5)2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-35482393

RESUMEN

Holocene climate warming has dramatically altered biological diversity and distributions. Recent human-induced emissions of greenhouse gases will exacerbate global warming and thus induce threats to cold-adapted taxa. However, the impacts of this major climate change on transcontinental temperate species are still poorly understood. Here, we generated extensive genomic datasets for a water strider, Aquarius paludum, which was sampled across its entire distribution in Eurasia and used these datasets in combination with ecological niche modeling (ENM) to elucidate the influence of the Holocene and future climate warming on its population structure and demographic history. We found that A. paludum consisted of two phylogeographic lineages that diverged in the middle Pleistocene, which resulted in a "west-east component" genetic pattern that was probably triggered by Central Asia-Mongoxin aridification and Pleistocene glaciations. The diverged western and eastern lineages had a second contact in the Holocene, which shaped a temporary hybrid zone located at the boundary of the arid-semiarid regions of China. Future predictions detected a potentially novel northern corridor to connect the western and eastern populations, indicating west-east gene flow would possibly continue to intensify under future warming climate conditions. Further integrating phylogeographic and ENM analyses of multiple Eurasian temperate taxa based on published studies reinforced our findings on the "west-east component" genetic pattern and the predicted future northern corridor for A. paludum. Our study provided a detailed paradigm from a phylogeographic perspective of how transcontinental temperate species differ from cold-adapted taxa in their response to climate warming.


Asunto(s)
Biodiversidad , Agua , Comunicación , Ecosistema , Variación Genética , Humanos , Filogenia , Filogeografía
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