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1.
Cell ; 184(18): 4734-4752.e20, 2021 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-34450029

RESUMEN

Immune responses to cancer are highly variable, with mismatch repair-deficient (MMRd) tumors exhibiting more anti-tumor immunity than mismatch repair-proficient (MMRp) tumors. To understand the rules governing these varied responses, we transcriptionally profiled 371,223 cells from colorectal tumors and adjacent normal tissues of 28 MMRp and 34 MMRd individuals. Analysis of 88 cell subsets and their 204 associated gene expression programs revealed extensive transcriptional and spatial remodeling across tumors. To discover hubs of interacting malignant and immune cells, we identified expression programs in different cell types that co-varied across tumors from affected individuals and used spatial profiling to localize coordinated programs. We discovered a myeloid cell-attracting hub at the tumor-luminal interface associated with tissue damage and an MMRd-enriched immune hub within the tumor, with activated T cells together with malignant and myeloid cells expressing T cell-attracting chemokines. By identifying interacting cellular programs, we reveal the logic underlying spatially organized immune-malignant cell networks.


Asunto(s)
Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/patología , Proteínas Morfogenéticas Óseas/metabolismo , Fibroblastos Asociados al Cáncer/metabolismo , Fibroblastos Asociados al Cáncer/patología , Compartimento Celular , Línea Celular Tumoral , Quimiocinas/metabolismo , Estudios de Cohortes , Neoplasias Colorrectales/genética , Reparación de la Incompatibilidad de ADN/genética , Células Endoteliales/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunidad , Inflamación/patología , Monocitos/patología , Células Mieloides/patología , Neutrófilos/patología , Células del Estroma/metabolismo , Linfocitos T/metabolismo , Transcripción Genética
2.
Plant Cell ; 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38299372

RESUMEN

Alternative complex III (ACIII) couples quinol oxidation and electron acceptor reduction with potential transmembrane proton translocation. It is compositionally and structurally different from the cytochrome bc1/b6f complexes, but functionally replaces these enzymes in the photosynthetic and/or respiratory electron transport chains (ETCs) of many bacteria. However, the true compositions and architectures of ACIIIs remain unclear, as do their structural and functional relevance in mediating the ETCs. We here determined cryogenic electron microscopy structures of photosynthetic ACIII isolated from Chloroflexus aurantiacus (CaACIIIp), in apo-form and in complexed form bound to a menadiol analog 2-heptyl-4-hydroxyquinoline-N-oxide (HQNO). Besides six canonical subunits (ActABCDEF), the structures revealed conformations of two previously unresolved subunits, ActG and I, which contributed to the complex stability. We also elucidated the structural basis of menaquinol oxidation and subsequent electron transfer along the [3Fe-4S]-6 hemes wire to its periplasmic electron acceptors, using electron paramagnetic resonance (EPR), spectroelectrochemistry, enzymatic analyses and molecular dynamics (MD) simulations. A unique insertion loop in ActE was shown to function in determining the binding specificity of CaACIIIp for downstream electron acceptors. This study broadens our understanding of the structural diversity and molecular evolution of ACIIIs, enabling further investigation of the (mena)quinol oxidoreductases evolved coupling mechanism in bacterial energy conservation.

3.
Nature ; 595(7866): 309-314, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33953401

RESUMEN

Epigenetic dysregulation is a defining feature of tumorigenesis that is implicated in immune escape1,2. Here, to identify factors that modulate the immune sensitivity of cancer cells, we performed in vivo CRISPR-Cas9 screens targeting 936 chromatin regulators in mouse tumour models treated with immune checkpoint blockade. We identified the H3K9 methyltransferase SETDB1 and other members of the HUSH and KAP1 complexes as mediators of immune escape3-5. We also found that amplification of SETDB1 (1q21.3) in human tumours is associated with immune exclusion and resistance to immune checkpoint blockade. SETDB1 represses broad domains, primarily within the open genome compartment. These domains are enriched for transposable elements (TEs) and immune clusters associated with segmental duplication events, a central mechanism of genome evolution6. SETDB1 loss derepresses latent TE-derived regulatory elements, immunostimulatory genes, and TE-encoded retroviral antigens in these regions, and triggers TE-specific cytotoxic T cell responses in vivo. Our study establishes SETDB1 as an epigenetic checkpoint that suppresses tumour-intrinsic immunogenicity, and thus represents a candidate target for immunotherapy.


Asunto(s)
Silenciador del Gen , N-Metiltransferasa de Histona-Lisina/metabolismo , Neoplasias/genética , Neoplasias/inmunología , Animales , Antígenos Virales/inmunología , Sistemas CRISPR-Cas/genética , Cromatina/genética , Cromatina/metabolismo , Elementos Transponibles de ADN/genética , Modelos Animales de Enfermedad , Femenino , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Ratones , Neoplasias/tratamiento farmacológico , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Linfocitos T Citotóxicos/citología , Linfocitos T Citotóxicos/inmunología
4.
Genome Res ; 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38129076

RESUMEN

Mammalian sperm show an unusual and heavily compacted genomic packaging state. In addition to its role in organizing the compact and hydrodynamic sperm head, it has been proposed that sperm chromatin architecture helps to program gene expression in the early embryo. Scores of genome-wide surveys in sperm have reported patterns of chromatin accessibility, nucleosome localization, histone modification, and chromosome folding. Here, we revisit these studies in light of recent reports that sperm obtained from the mouse epididymis are contaminated with low levels of cell-free chromatin. In the absence of proper sperm lysis, we readily recapitulate multiple prominent genome-wide surveys of sperm chromatin, suggesting that these profiles primarily reflect contaminating cell-free chromatin. Removal of cell-free DNA, and appropriate lysis conditions, are together required to reveal a sperm chromatin state distinct from most previous reports. Using ATAC-seq to explore relatively accessible genomic loci, we identify a landscape of open loci associated with early development and transcriptional control. Histone modification and chromosome folding profiles also strongly support the hypothesis that prior studies suffer from contamination, but technical challenges associated with reliably preserving the architecture of the compacted sperm head prevent us from confidently assaying true localization patterns for these epigenetic marks. Together, our studies show that our knowledge of chromosome packaging in mammalian sperm remains largely incomplete, and motivate future efforts to more accurately characterize genome organization in mature sperm.

5.
Nature ; 587(7832): 139-144, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33116310

RESUMEN

Zygotic genome activation (ZGA) is the first transcription event in life1. However, it is unclear how RNA polymerase is engaged in initiating ZGA in mammals. Here, by developing small-scale Tn5-assisted chromatin cleavage with sequencing (Stacc-seq), we investigated the landscapes of RNA polymerase II (Pol II) binding in mouse embryos. We found that Pol II undergoes 'loading', 'pre-configuration', and 'production' during the transition from minor ZGA to major ZGA. After fertilization, Pol II is preferentially loaded to CG-rich promoters and accessible distal regions in one-cell embryos (loading), in part shaped by the inherited parental epigenome. Pol II then initiates relocation to future gene targets before genome activation (pre-configuration), where it later engages in full transcription elongation upon major ZGA (production). Pol II also maintains low poising at inactive promoters after major ZGA until the blastocyst stage, coinciding with the loss of promoter epigenetic silencing factors. Notably, inhibition of minor ZGA impairs the Pol II pre-configuration and embryonic development, accompanied by aberrant retention of Pol II and ectopic expression of one-cell targets upon major ZGA. Hence, stepwise transition of Pol II occurs when mammalian life begins, and minor ZGA has a key role in the pre-configuration of transcription machinery and chromatin for genome activation.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica/genética , Genoma/genética , ARN Polimerasa II/metabolismo , Cigoto/metabolismo , Alelos , Animales , Cromatina/genética , Cromatina/metabolismo , Embrión de Mamíferos/citología , Embrión de Mamíferos/enzimología , Embrión de Mamíferos/metabolismo , Epigenoma/genética , Femenino , Masculino , Herencia Materna/genética , Ratones , Ratones Endogámicos C57BL , Oocitos/enzimología , Oocitos/metabolismo , Regiones Promotoras Genéticas/genética , ARN Polimerasa II/genética , Cigoto/citología , Cigoto/enzimología
6.
Small ; 20(23): e2308484, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38143292

RESUMEN

Prussian blue analogs (PBAs) show great promise as anode materials for potassium-ion batteries (PIBs) due to their high specific capacity. However, PBAs still suffer from the drawbacks of low electronic conductivity and poor structural stability, leading to inadequate rate and cyclic performance. To address these limitations, CoFe PBA nanocubes wrapped with N/S doped carbon network (CoFe PBA@NSC) as anode for PIBs is designed by using thermal-induced in situ conversion strategy. As expected, the structural advantages of nanosized PBA cubes, such as abundant interfaces and large surface area, enable the CoFe PBA@NSC electrode to demonstrate superior rate properties (557 and 131 mAh g-1 at 0.05 and 10 A g-1) and low capacity degradation (0.093% per cycle over 1000 cycles at 0.5 A g-1). Furthermore, several ex situ characterizations revealed the K-ion storage mechanism. Fe+ and Co0 are generated during potassicization, followed by a completely reversible chemical state of iron while some cobalt monomers remained during depotassication. Additionally, the as-built potassium-ion hybrid capacitor based on CoFe PBA@NSC anode exhibits a high energy density of 118 Wh kg-1. This work presents an alternative but promising synthesis route for Prussian blue analogs, which is significant for the advancement of PIBs and other related energy storage devices.

7.
Small ; : e2400767, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38676351

RESUMEN

Fluorides are viewed as promising conversion-type Li-ion battery cathodes to meet the desired high energy density. FeOF is a typical member of conversion-type fluorides, but its major drawback is sluggish kinetics upon deep discharge. Herein, a heterostructured FeOF-MXene composite (FeOF-MX) is demonstrated to overcome this limitation. The rationally designed FeOF-MX electrode features a microsphere morphology consisting of closely packed FeOF nanoparticles, providing fast transport pathways for lithium ions while a continuous wrapping network of MXene nanosheets ensures unobstructed electron transport, thus enabling high-rate lithium storage with enhanced pseudocapacitive contribution. In/ex situ characterization techniques and theoretical calculations, both reveal that the lithium storage mechanism in FeOF arises from a hybrid intercalation-conversion process, and strong interfacial interactions between FeOF and MXene promote Li-ion adsorption and migration. Remarkably, through demarcating the conversion-type reaction with a controlled potential window, a symmetric full battery with prelithiated FeOF-MX as both cathode and anode is fabricated, achieving a high energy density of 185.5 Wh kg-1 and impressive capacity retention of 88.9% after 3000 cycles at 1 A g-1. This work showcases an effective route toward high-performance MXene engineered fluoride-based electrodes and provides new insights into constructing symmetric batteries yet with high-energy/power densities.

8.
Nature ; 560(7718): E27, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29925957

RESUMEN

In this Letter, the 'Open chromatin' label in Fig. 4a should have been centred above the first three columns, and the black horizontal line underneath the label should have been removed. In addition, there should have been a vertical black line between the last two sets of panels for consistency. Minor changes have also been made to Fig. 1 and to the legend of Fig. 3. These errrors have been corrected online, and see Supplementary Information to the accompanying Amendment for the original Fig. 4.

9.
Nature ; 557(7704): 256-260, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29720659

RESUMEN

Upon fertilization, drastic chromatin reorganization occurs during preimplantation development 1 . However, the global chromatin landscape and its molecular dynamics in this period remain largely unexplored in humans. Here we investigate chromatin states in human preimplantation development using an improved assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq) 2 . We find widespread accessible chromatin regions in early human embryos that overlap extensively with putative cis-regulatory sequences and transposable elements. Integrative analyses show both conservation and divergence in regulatory circuitry between human and mouse early development, and between human pluripotency in vivo and human embryonic stem cells. In addition, we find widespread open chromatin regions before zygotic genome activation (ZGA). The accessible chromatin loci are readily found at CpG-rich promoters. Unexpectedly, many others reside in distal regions that overlap with DNA hypomethylated domains in human oocytes and are enriched for transcription factor-binding sites. A large portion of these regions then become inaccessible after ZGA in a transcription-dependent manner. Notably, such extensive chromatin reorganization during ZGA is conserved in mice and correlates with the reprogramming of the non-canonical histone mark H3K4me3, which is uniquely linked to genome silencing3-5. Taken together, these data not only reveal a conserved principle that underlies the chromatin transition during mammalian ZGA, but also help to advance our understanding of epigenetic reprogramming during human early development and in vitro fertilization.


Asunto(s)
Cromatina/genética , Cromatina/metabolismo , Embrión de Mamíferos/metabolismo , Desarrollo Embrionario/genética , Epigénesis Genética , Genoma/genética , Cigoto/metabolismo , Animales , Sitios de Unión , Islas de CpG/genética , Metilación de ADN , Embrión de Mamíferos/citología , Embrión de Mamíferos/embriología , Células Madre Embrionarias/citología , Femenino , Silenciador del Gen , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Ratones , Oocitos/citología , Oocitos/metabolismo , Células Madre Pluripotentes/citología , Regiones Promotoras Genéticas/genética , Factores de Transcripción/metabolismo , Transposasas/metabolismo
10.
Sensors (Basel) ; 24(10)2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38793907

RESUMEN

(1) Background: This study evaluates the effectiveness of low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) in improving gait in post-stroke hemiplegic patients, using wearable sensor technology for objective gait analysis. (2) Methods: A total of 72 stroke patients were randomized into control, sham stimulation, and LF-rTMS groups, with all receiving standard medical treatment. The LF-rTMS group underwent stimulation on the unaffected hemisphere for 6 weeks. Key metrics including the Fugl-Meyer Assessment Lower Extremity (FMA-LE), Berg Balance Scale (BBS), Modified Barthel Index (MBI), and gait parameters were measured before and after treatment. (3) Results: The LF-rTMS group showed significant improvements in the FMA-LE, BBS, MBI, and various gait parameters compared to the control and sham groups (p < 0.05). Specifically, the FMA-LE scores improved by an average of 5 points (from 15 ± 3 to 20 ± 2), the BBS scores increased by 8 points (from 35 ± 5 to 43 ± 4), the MBI scores rose by 10 points (from 50 ± 8 to 60 ± 7), and notable enhancements in gait parameters were observed: the gait cycle time was reduced from 2.05 ± 0.51 s to 1.02 ± 0.11 s, the stride length increased from 0.56 ± 0.04 m to 0.97 ± 0.08 m, and the walking speed improved from 35.95 ± 7.14 cm/s to 75.03 ± 11.36 cm/s (all p < 0.001). No adverse events were reported. The control and sham groups exhibited improvements but were not as significant. (4) Conclusions: LF-rTMS on the unaffected hemisphere significantly enhances lower-limb function, balance, and daily living activities in subacute stroke patients, with the gait parameters showing a notable improvement. Wearable sensor technology proves effective in providing detailed, objective gait analysis, offering valuable insights for clinical applications in stroke rehabilitation.


Asunto(s)
Marcha , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Estimulación Magnética Transcraneal , Dispositivos Electrónicos Vestibles , Humanos , Masculino , Femenino , Estimulación Magnética Transcraneal/métodos , Estimulación Magnética Transcraneal/instrumentación , Persona de Mediana Edad , Accidente Cerebrovascular/fisiopatología , Accidente Cerebrovascular/terapia , Marcha/fisiología , Anciano , Rehabilitación de Accidente Cerebrovascular/instrumentación , Rehabilitación de Accidente Cerebrovascular/métodos , Análisis de la Marcha/métodos
11.
Molecules ; 29(10)2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38792108

RESUMEN

Dye/salt separation has gained increasing attention in recent years, prompting the quest to find cost-effective and environmentally friendly raw materials for synthesizing high performance nanofiltration (NF) membrane for effective dye/salt separation. Herein, a high-performance loose-structured NF membrane was fabricated via a simple vacuum filtration method using a green nanomaterial, 2,2,6,6-tetramethylpiperidine-1-oxide radical (TEMPO)-oxidized cellulose nanofiber (TOCNF), by sequentially filtrating larger-sized and finer-sized TOCNFs on a microporous substrate, followed by crosslinking with trimesoyl chloride. The resulting TCM membrane possessed a separating layer composed entirely of pure TOCNF, eliminating the need for other polymer or nanomaterial additives. TCM membranes exhibit high performance and effective dye/salt selectivity. Scanning Electron Microscope (SEM) analysis shows that the TCM membrane with the Fine-TOCNF layer has a tight layered structure. Further characterizations via Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) confirmed the presence of functional groups and chemical bonds of the crosslinked membrane. Notably, the optimized TCM-5 membrane exhibits a rejection rate of over 99% for various dyes (Congo red and orange yellow) and 14.2% for NaCl, showcasing a potential candidate for efficient dye wastewater treatment.

12.
BMC Genomics ; 24(1): 163, 2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37013486

RESUMEN

BACKGROUND: Epithelium-mesenchymal interactions are involved in odontogenic processes. Previous studies have focused on the intracellular signalling regulatory network in tooth development, but the functions of extracellular regulatory molecules have remained unclear. This study aims to explore the gene profile of extracellular proteoglycans and their glycosaminoglycan chains potentially involved in dental epithelium-mesenchymal interactions using high-throughput sequencing to provide new understanding of early odontogenesis. RESULTS: Whole transcriptome profiles of the mouse dental epithelium and mesenchyme were investigated by RNA sequencing (RNA-seq). A total of 1,281 and 1,582 differentially expressed genes were identified between the dental epithelium and mesenchyme at E11.5 and E13.5, respectively. Enrichment analysis showed that extracellular regions and ECM-receptor interactions were significantly enriched at both E11.5 and E13.5. Polymerase chain reaction analysis confirmed that the extracellular proteoglycan family exhibited distinct changes during epithelium-mesenchymal interactions. Most proteoglycans showed higher transcript levels in the dental mesenchyme, whereas only a few were upregulated in the epithelium at both stages. In addition, 9 proteoglycans showed dynamic expression changes between these two tissue compartments. Gpc4, Sdc2, Spock2, Dcn and Lum were expressed at higher levels in the dental epithelium at E11.5, whereas their expression was significantly higher in the dental mesenchyme at E13.5, which coincides with the odontogenic potential shift. Moreover, the glycosaminoglycan biosynthetic enzymes Ext1, Hs3st1/5, Hs6st2/3, Ndst3 and Sulf1 also exhibited early upregulation in the epithelium but showed markedly higher expression in the mesenchyme after the odontogenic potential shift. CONCLUSION: This study reveals the dynamic expression profile of extracellular proteoglycans and their biosynthetic enzymes during the dental epithelium-mesenchymal interaction. This study offers new insight into the roles of extracellular proteoglycans and their distinct sulfation underlying early odontogenesis.


Asunto(s)
Odontogénesis , Diente , Ratones , Animales , Epitelio/metabolismo , Odontogénesis/genética , Proteoglicanos/genética , Proteoglicanos/metabolismo , Transducción de Señal , Glicosaminoglicanos/metabolismo
13.
J Am Chem Soc ; 145(16): 9112-9117, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37058550

RESUMEN

Covalent adaptable networks (CANs) represent a novel class of polymeric materials crosslinked by dynamic covalent bonds. Since their first discovery, CANs have attracted great attention due to their high mechanical strength and stability like conventional thermosets under service conditions and easy reprocessability like thermoplastics under certain external stimuli. Here, we report the first example of ionic covalent adaptable networks (ICANs), a type of crosslinked ionomers, consisting of negatively charged backbone structures. More specifically, two ICANs with different backbone compositions were prepared through spiroborate chemistry. Given the dynamic nature of the spiroborate linkages, the resulting ionomer thermosets display rapid reprocessability and closed-loop recyclability under mild conditions. The materials mechanically broken into smaller pieces can be reprocessed into coherent solids at 120 °C within only 1 min with nearly 100% recovery of the mechanical properties. Upon treating the ICANs with dilute hydrochloric acid at room temperature, the valuable monomers can be easily chemically recycled in almost quantitative yield. This work demonstrates the great potential of spiroborate bonds as a novel dynamic ionic linkage for development of new reprocessable and recyclable ionomer thermosets.

14.
BMC Cardiovasc Disord ; 23(1): 270, 2023 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-37221473

RESUMEN

BACKGROUND: Hypertension affects 31.1% of adults worldwide, with higher prevalence of great than 60% in elderly. Advanced hypertension stage was associated with the higher risk of mortality. However, little is known about the age-specific association of stage of hypertension at diagnosis on cardiovascular mortality or all-cause mortality. Therefore, we aim to explore this age-specific association among the hypertensive elderly through stratified and interaction analyses. METHODS: This cohort study included 125,978 elderly hypertensive patients aged 60+ years from Shanghai of China. Cox regression was used to estimate the independent and joint effect of hypertension stage and age at diagnosis on cardiovascular and all-cause mortality. Interactions were evaluated both additively and multiplicatively. Multiplicative interaction was examined by the Wald test of the interaction term. Additive interaction was assessed by relative excess risk due to interaction (RERI). All analyses were performed stratified by sex. RESULTS: 28,250 patients died during the follow-up up to 8.85 years, and 13,164 died of cardiovascular events. Older age and advanced hypertension stage were risk factors of cardiovascular mortality and all-cause mortality. Besides, smoking, rarely exercise, BMI < 18.5 and diabetes were also the risk factors. When we compared stage 3 hypertension with stage 1 hypertension, hazard ratios (95% confidence interval) of cardiovascular mortality and all-cause mortality were 1.56(1.41-1.72) and 1.29(1.21-1.37) for males aged 60-69 years, 1.25(1.14-1.36) and 1.13(1.06-1.20) for males aged 70-85 years, 1.48(1.32-1.67) and 1.29(1.19-1.40) for females aged 60-69 years, and 1.19(1.10-1.29) and 1.08(1.01-1.15) for females aged 70-85 years, respectively. Negative multiplicative interaction and positive additive interaction between age at diagnosis and stage of hypertension at diagnosis on cardiovascular mortality were observed in males (HR: 0.81, 95% CI: 0.71-0.93 RERI: 0.59, 95% CI: 0.09-1.07) and females (HR: 0.81, 95% CI: 0.70-0.93 RERI: 0.66, 95% CI: 0.10-1.23). CONCLUSIONS: Diagnosed with stage 3 hypertension was associated with higher risks of cardiovascular mortality and all-cause mortality, which were stronger among patients with age at diagnosis of 60-69 years compared with those with age at diagnosis of 70-85 years. Therefore, for the younger part of the elderly, the Department of Health should pay more attention to treating patients with stage 3 hypertension.


Asunto(s)
Sistema Cardiovascular , Hipertensión , Adulto , Anciano , Femenino , Masculino , Humanos , Estudios de Cohortes , China , Factores de Edad
15.
Nature ; 547(7662): 232-235, 2017 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-28703188

RESUMEN

In mammals, chromatin organization undergoes drastic reprogramming after fertilization. However, the three-dimensional structure of chromatin and its reprogramming in preimplantation development remain poorly understood. Here, by developing a low-input Hi-C (genome-wide chromosome conformation capture) approach, we examined the reprogramming of chromatin organization during early development in mice. We found that oocytes in metaphase II show homogeneous chromatin folding that lacks detectable topologically associating domains (TADs) and chromatin compartments. Strikingly, chromatin shows greatly diminished higher-order structure after fertilization. Unexpectedly, the subsequent establishment of chromatin organization is a prolonged process that extends through preimplantation development, as characterized by slow consolidation of TADs and segregation of chromatin compartments. The two sets of parental chromosomes are spatially separated from each other and display distinct compartmentalization in zygotes. Such allele separation and allelic compartmentalization can be found as late as the 8-cell stage. Finally, we show that chromatin compaction in preimplantation embryos can partially proceed in the absence of zygotic transcription and is a multi-level hierarchical process. Taken together, our data suggest that chromatin may exist in a markedly relaxed state after fertilization, followed by progressive maturation of higher-order chromatin architecture during early development.


Asunto(s)
Alelos , Ensamble y Desensamble de Cromatina/genética , Cromatina/química , Cromatina/genética , Cromosomas de los Mamíferos/química , Cromosomas de los Mamíferos/genética , Desarrollo Embrionario/genética , Animales , Blastocisto/metabolismo , Cromatina/metabolismo , Cromosomas de los Mamíferos/metabolismo , Femenino , Fertilización , Regulación del Desarrollo de la Expresión Génica , Masculino , Ratones , Transcripción Genética , Cigoto/metabolismo
16.
Environ Res ; 220: 115172, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36584849

RESUMEN

In alkaline soil, abundant carbonates will mobilize uranium (U) and increase its ecotoxicity, which is a serious threat to crop growth. However, the knowledge of U remediation in alkaline soils remains very limited. In this study, U-contaminated alkaline soil (tillage layer) was collected from the Ili mining area of Xinjiang, the soil remediation was carried out by using phosphorus (P) fertilizers of different solubility (including KH2PO4, Ca(H2PO4)2, CaHPO4, and Ca3(PO4)2), and the pathways and mechanisms of U passivation in the alkaline soil were revealed. The results showed that water-soluble P fertilizers, KH2PO4 and Ca(H2PO4)2, were highly effective at immobilizing U, and significantly reduced the bioavailability of soil U. The exchangeable U was reduced by 70.5 ± 0.1% (KH2PO4) and 68.2 ± 1.9% (Ca(H2PO4)2), which was converted into the Fe-Mn oxide-bound and residual phases. Pot experiments showed that soil remediation by KH2PO4 significantly promoted crop growth, especially for roots, and reduced U uptake in crops by 94.5 ± 1.0%. The immobilization of U by KH2PO4 could be attributed to the release of phosphate anions, which react with the uranyl ion (UO22+) forming a stable mineral of meta-ankoleite and enhancing the binding of UO22+ to the soil Fe-Mn oxides. In addition, KH2PO4 dissolution produces acidity and P fertilizer, which can reduce soil alkalinity and improve crop growth. The findings in this work demonstrate that a rational application of P fertilizer can effectively, conveniently, and cheaply remediate U contamination and improve crop yield and safety on alkaline farmland.


Asunto(s)
Contaminantes del Suelo , Uranio , Fósforo , Fertilizantes/análisis , Contaminantes del Suelo/análisis , Suelo
17.
Appl Microbiol Biotechnol ; 107(2-3): 553-567, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36517545

RESUMEN

Recombinant protein drugs, which are typically produced by mammalian host cells, have been approved for the treatment of a range of diseases. Accordingly, systems for selecting recombinant cell lines with efficient protein expression and for testing the content of recombinant proteins in vivo are crucial to the large-scale production and application of protein-based therapeutic drugs. In this study, we designed three aptamer beacons to detect His-tag, a common label of recombinant proteins. We found that all three beacons could specifically and quantitatively measure the His-tagged recombinant proteins with a short reaction time. Among these three beacons, the 6H5-MU beacon had the highest sensitivity for His polypeptides with a detection limit of 250 ng/mL and the shortest detection time within 1 min. Furthermore, we established a rapid and highly effective recombinant cell line construction system, which could obtain monoclonal cell lines with high yields of target proteins within 21 days, by combining 6H5-MU with pSB, a novel plasmid composed of a Sleeping Beauty transposase and a transposon. Finally, 6H5-MU also discriminately tested the serum concentration of His-tagged recombinant proteins in vivo, with consistent results compared to enzyme-linked immunosorbent assay (ELISA). We thus established a rapid and high-throughput method for generating recombinant cell lines and in vivo monitoring of recombinant protein levels, thereby providing a new platform for the development and preparation of recombinant protein drugs. KEY POINTS: • The 6H5-MU aptamer beacon rapidly and accurately binds to His-tagged recombinant proteins. • A system for rapid and high-throughput generation of recombinant cell lines is established using 6H5-MU and pSB. • 6H5-MU allows in vivo monitoring of recombinant protein levels.


Asunto(s)
Mamíferos , Oligonucleótidos , Animales , Proteínas Recombinantes/genética , Línea Celular
18.
Hum Resour Health ; 21(1): 62, 2023 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-37553692

RESUMEN

OBJECTIVE: This study aims to characterize the current status of the nephrology workforce in China and evaluate its optimal capacity based on real-world patient mobility data. METHODS: Data on nephrologists in China were collected from two prominent online healthcare platforms using web crawlers and natural language processing techniques. Hospitalization records of patients with chronic kidney disease (CKD) from January 2014 to December 2018 were extracted from a national administrative database in China. City-level paths of patient mobility were identified. Effects of nephrology workforce on patient mobility were analyzed using multivariate Poisson regression models. RESULTS: Altogether 9.13 nephrologists per million population (pmp) were in practice, with substantial city-level variations ranging from 0.16 to 88.79. The ratio of nephrologists to the estimated CKD population was 84.57 pmp. Among 6 415 559 hospitalizations of patients with CKD, 21.3% were cross-city hospitalizations and 7441 city-level paths of patient mobility with more than five hospitalizations were identified. After making adjustment for healthcare capacity, healthcare insurance, economic status, and travel characteristics, the Poisson regression models revealed that the number of nephrologists in both the source city (incidence rate ratio [IRR] 0.99, per 1 pmp increase) and destination city (IRR 1.07, per 1 pmp increase) were independently associated with patient mobility. An IRR plateau was observed when the number of nephrologists exceeded 12 pmp in the source city, while a rapidly increasing IRR was observed beyond 20 pmp in the destination city. CONCLUSIONS: The nephrology workforce in China exhibits significant geographic variations. Based on local healthcare needs, an optimal range of 12-20 nephrologists pmp is suggested.


Asunto(s)
Nefrología , Insuficiencia Renal Crónica , Humanos , Nefrología/métodos , Diálisis Renal , Limitación de la Movilidad , Insuficiencia Renal Crónica/terapia , Recursos Humanos
19.
Graefes Arch Clin Exp Ophthalmol ; 261(6): 1651-1658, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36627493

RESUMEN

PURPOSE: To evaluate the agreement between swept-source OCT (CASIA2) and UBM in primary angle-closure glaucoma. METHODS: Eighty eyes of 40 participants diagnosed with primary angle-closure glaucoma were examined. Parameters measured included angle opening distance (AOD), angle recess area (ARA), trabecular iris space area (TISA), trabecular iris angle (TIA), lens vault (LV), anterior chamber depth (ACD), and anterior chamber width (ACW). Angle images of nasal, temporal, superior, and inferior were acquired by the anterior segment mode of CASIA2 and UBM. One-way analysis of variance and paired t-test were used for statistical analysis, and the agreement was analyzed by internal correlation coefficient (ICC) and Bland-Altman method. RESULTS: One-way ANOVA pairwise comparison showed that CASIA2 or UBM had the narrowest superior chamber angle and the widest temporal chamber angle in patients with primary angle-closure glaucoma. The paired t-test showed that inter-device AOD, TIA, ARA, and TISA of superior chamber angle had significant differences (p < 0.001). There was no significant difference in the measured values of LV, ACD, and ACW (p > 0.05). The agreement of all parameters is good through the Bland-Altman method comparison. ICC result showed moderate agreement in other angle parameters except for superior ARA500 (0.739). CONCLUSION: In the anterior chamber angle measurement process, we should pay more attention to the superior chamber angle covered by eyelids. Although the agreement is acceptable between CASIA2 and UBM, the measurements could not be considered interchangeable due to the tremendous statistical difference between the two devices.


Asunto(s)
Glaucoma de Ángulo Cerrado , Cristalino , Humanos , Tomografía de Coherencia Óptica/métodos , Glaucoma de Ángulo Cerrado/diagnóstico , Microscopía Acústica , Cámara Anterior/diagnóstico por imagen , Segmento Anterior del Ojo/diagnóstico por imagen , Iris/diagnóstico por imagen , Gonioscopía
20.
Nephrology (Carlton) ; 28(9): 477-484, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37254566

RESUMEN

AIM: This study aimed to investigate the incidence of relapse and FR/SDNS in Chinese children with SSNS and to develop clinical prediction models for relapse and FR/SDNS. METHODS: This retrospective cohort study involved 339 newly onset SSNS patients between 2006 and 2016. The incidence of relapse and FR/SDNS were estimated using the Kaplan-Meier method. Prediction models were constructed based on Cox proportional-hazards regression. RESULTS: The median follow-up time was 8.7 years. The cumulative incidence of relapse at 1-, 2-, and 5-year was 51.0%, 62.5%, and 66.6%. The cumulative incidence of FR/SDNS at 1-, 2-, and 5-year was 18.4%, 29.0%, and 32.9%. The final prediction model for first relapse included four variables (serum albumin, triglycerides, IgM, and time to first remission). The model's discriminative ability was low (Harrell's C index = 0.62). The final prediction model for FR/SDNS included four variables (serum albumin, lipoprotein(a), time to first remission, and time to first relapse). The discrimination and calibration of the prediction model for FR/SDNS were acceptable (Harrell's C index = 0.73, Brier score at 1- and 2-year were 0.11 and 0.17). CONCLUSION: The first relapse and FR/SDNS mainly occurred in the first 2 years after initial SSNS onset. The prediction model for relapse developed using common clinical parameters performed poorly, while the prediction model for FR/SDNS might be useful.


Asunto(s)
Síndrome Nefrótico , Niño , Humanos , Síndrome Nefrótico/diagnóstico , Síndrome Nefrótico/tratamiento farmacológico , Síndrome Nefrótico/epidemiología , Incidencia , Estudios de Cohortes , Estudios Retrospectivos , Pueblos del Este de Asia , Recurrencia , Inmunosupresores
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