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1.
Cell ; 184(18): 4734-4752.e20, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34450029

RESUMO

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.


Assuntos
Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Proteínas Morfogenéticas Ósseas/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Compartimento Celular , Linhagem Celular Tumoral , Quimiocinas/metabolismo , Estudos de Coortes , Neoplasias Colorretais/genética , Reparo de Erro de Pareamento de DNA/genética , Células Endoteliais/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Imunidade , Inflamação/patologia , Monócitos/patologia , Células Mieloides/patologia , Neutrófilos/patologia , Células Estromais/metabolismo , Linfócitos T/metabolismo , Transcrição Gênica
2.
Plant Cell ; 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38299372

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-33953401

RESUMO

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.


Assuntos
Inativação Gênica , Histona-Lisina N-Metiltransferase/metabolismo , Neoplasias/genética , Neoplasias/imunologia , Animais , Antígenos Virais/imunologia , Sistemas CRISPR-Cas/genética , Cromatina/genética , Cromatina/metabolismo , Elementos de DNA Transponíveis/genética , Modelos Animais de Doenças , Feminino , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Camundongos , Neoplasias/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/imunologia
4.
Proc Natl Acad Sci U S A ; 121(34): e2409341121, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39145939

RESUMO

Vesicular transport relies on multimeric trafficking complexes to capture cargo and drive vesicle budding and fusion. Faithful assembly of the trafficking complexes is essential to their functions but remains largely unexplored. Assembly of AP2 adaptor, a heterotetrameric protein complex regulating clathrin-mediated endocytosis, is assisted by the chaperone AAGAB. Here, we found that AAGAB initiates AP2 assembly by stabilizing its α and σ2 subunits, but the AAGAB:α:σ2 complex cannot recruit additional AP2 subunits. We identified CCDC32 as another chaperone regulating AP2 assembly. CCDC32 recognizes the AAGAB:α:σ2 complex, and its binding leads to the formation of an α:σ2:CCDC32 ternary complex. The α:σ2:CCDC32 complex serves as a template that sequentially recruits the µ2 and ß2 subunits of AP2 to complete AP2 assembly, accompanied by CCDC32 release. The AP2-regulating function of CCDC32 is disrupted by a disease-causing mutation. These findings demonstrate that AP2 is assembled by a handover mechanism switching from AAGAB-based initiation complexes to CCDC32-based template complexes. A similar mechanism may govern the assembly of other trafficking complexes exhibiting the same configuration as AP2.


Assuntos
Complexo 2 de Proteínas Adaptadoras , Chaperonas Moleculares , Complexo 2 de Proteínas Adaptadoras/metabolismo , Complexo 2 de Proteínas Adaptadoras/genética , Humanos , Chaperonas Moleculares/metabolismo , Chaperonas Moleculares/genética , Ligação Proteica , Endocitose/fisiologia , Transporte Proteico
5.
Genome Res ; 33(12): 2079-2093, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38129076

RESUMO

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.


Assuntos
Cromatina , Espermatozoides , Masculino , Animais , Camundongos , Espermatozoides/metabolismo , Cromatina/metabolismo , Cromatina/genética , Montagem e Desmontagem da Cromatina , Código das Histonas , Histonas/metabolismo
6.
Nature ; 587(7832): 139-144, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33116310

RESUMO

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.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento/genética , Genoma/genética , RNA Polimerase II/metabolismo , Zigoto/metabolismo , Alelos , Animais , Cromatina/genética , Cromatina/metabolismo , Embrião de Mamíferos/citologia , Embrião de Mamíferos/enzimologia , Embrião de Mamíferos/metabolismo , Epigenoma/genética , Feminino , Masculino , Herança Materna/genética , Camundongos , Camundongos Endogâmicos C57BL , Oócitos/enzimologia , Oócitos/metabolismo , Regiões Promotoras Genéticas/genética , RNA Polimerase II/genética , Zigoto/citologia , Zigoto/enzimologia
7.
Small ; 20(23): e2308484, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38143292

RESUMO

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.

8.
Small ; : e2400767, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38676351

RESUMO

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.

9.
Artigo em Inglês | MEDLINE | ID: mdl-39058535

RESUMO

A polyphasic taxonomic approach was used to characterize the three bacterial strains (FP830T, FP2034, and FP2262) isolated from the rhizosphere soil of rice, corn, and highland barley in Beijing, Heilongjiang, and Tibet, respectively, in PR China. These strains were Gram-negative, rod-shaped, and have one or two polar flagella. They exhibited optimal growth at 28 °C and pH 7.0 in the presence of 1 % (w/v) NaCl and showed fluorescence under ultraviolet light when cultivated on King's B plates. The FP830T genome size is 6.4 Mbp with a G+C content of 61.0 mol%. FP830T has the potential to promote plant growth by producing various metabolites such as fengycin, pyoverdin, indole-3-acetic acid, and the volatile substance 2,3-butanediol. Phylogenetic analysis indicated that three isolates formed an independent branch, which most closely related to type strains Pseudomonas thivervalensis DSM 13194T and Pseudomonas zanjanensis SWRI12T. The values of average nucleotide identity and digital DNA-DNA hybridization between three isolates and closest relatives were not higher than 93.7 and 52.3 %, respectively. The dominant cellular fatty acids were C16 : 0, summed feature 3 (C16 : 1 ω7c/C16 : 1 ω6c), and summed feature 8 (C18 : 1 ω7c/C18 : 1 ω6c). The major polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, and aminophospholipid. The predominant respiratory quinone was ubiquinone (Q-9). Based on polyphasic taxonomic analysis, it was concluded that strains FP830T, FP2034, and FP2262 represented a novel species within the genus Pseudomonas, and Pseudomonas beijingensis sp. nov. was proposed for the name of novel species. The type strain is FP830T (=ACCC 62448T=JCM 35689T).


Assuntos
Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Hibridização de Ácido Nucleico , Oryza , Filogenia , Pseudomonas , RNA Ribossômico 16S , Rizosfera , Análise de Sequência de DNA , Microbiologia do Solo , Pseudomonas/genética , Pseudomonas/classificação , Pseudomonas/isolamento & purificação , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , China , Ácidos Graxos/análise , Oryza/microbiologia , Hordeum/microbiologia , Zea mays/microbiologia , Tibet
10.
Nature ; 557(7704): 256-260, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29720659

RESUMO

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.


Assuntos
Cromatina/genética , Cromatina/metabolismo , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/genética , Epigênese Genética , Genoma/genética , Zigoto/metabolismo , Animais , Sítios de Ligação , Ilhas de CpG/genética , Metilação de DNA , Embrião de Mamíferos/citologia , Embrião de Mamíferos/embriologia , Células-Tronco Embrionárias/citologia , Feminino , Inativação Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Camundongos , Oócitos/citologia , Oócitos/metabolismo , Células-Tronco Pluripotentes/citologia , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/metabolismo , Transposases/metabolismo
11.
Nature ; 560(7718): E27, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29925957

RESUMO

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.

12.
BMC Musculoskelet Disord ; 25(1): 633, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39118027

RESUMO

BACKGROUND: Postoperative delirium (POD) is a common surgical complication. However, the incidence and risk factors associated with postoperative delirium after revision total knee arthroplasty (rTKA) have not been comprehensively explored through extensive national databases. METHODS: Utilizing the National Inpatient Sample (NIS), the largest comprehensive U.S. hospital healthcare database, we undertook a retrospective investigation involving 127,400 patients who underwent rTKA between 2010 and 2019. We assessed various aspects, including patient demographics, hospital characteristics, pre-existing medical conditions, and perioperative complications. RESULTS: The overall incidence of postoperative delirium (POD) in patients undergoing rTKA between 2010 and 2019 was 0.97%. The highest incidence rate of 1.31% was recorded in 2013. Notably, this patient cohort demonstrated advanced age, increased burden of co-morbidities, prolonged hospital stays, increased hospitalization costs, and elevated in-hospital mortality rates (P < 0.001). Moreover, non-elective admissions, non-private insurance payments, and a preference for teaching hospitals were commonly observed among these patients. During their hospitalization, individuals who developed delirium subsequent to rTKA were more prone to experiencing certain perioperative complications. These complications encompassed medical issues like acute myocardial infarction, continuous invasive mechanical ventilation, postoperative shock, sepsis, stroke and other medical problems. Additionally, surgical complications including hemorrhage / seroma / hematoma, irrigation and debridement, prosthetic joint infection, periprosthetic fracture, and wound dehiscence / nonunion were noted. Several risk factors were found to be linked with the development of POD. These included advanced age (≥ 75 years), alcohol abuse, coagulation disorders, congestive heart failure, depression, fluid and electrolyte imbalances, and more. Conversely, female sex, having private insurance, and undergoing elective hospitalization emerged as protective factors against POD. CONCLUSION: Our findings suggest that the general prevalence of POD in rTKA is relatively low according to NIS. There was a significant connection between the POD of rTKA and advanced age, prolonged length of stay (LOS), more in-patients' costs, higher in-hospital mortality rate, increased comorbidities, postoperative medical complications and postoperative surgical complications. This study helps to understand the risk factors associated with POD to improve poor outcomes.


Assuntos
Artroplastia do Joelho , Bases de Dados Factuais , Delírio , Complicações Pós-Operatórias , Humanos , Artroplastia do Joelho/efeitos adversos , Masculino , Feminino , Estudos Retrospectivos , Fatores de Risco , Idoso , Pessoa de Meia-Idade , Incidência , Estados Unidos/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Delírio/epidemiologia , Delírio/etiologia , Reoperação/estatística & dados numéricos , Idoso de 80 Anos ou mais , Pacientes Internados , Adulto , Tempo de Internação , Mortalidade Hospitalar
13.
Sensors (Basel) ; 24(10)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38793907

RESUMO

(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.


Assuntos
Marcha , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Estimulação Magnética Transcraniana , Dispositivos Eletrônicos Vestíveis , Humanos , Masculino , Feminino , Estimulação Magnética Transcraniana/métodos , Estimulação Magnética Transcraniana/instrumentação , Pessoa de Meia-Idade , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia , Marcha/fisiologia , Idoso , Reabilitação do Acidente Vascular Cerebral/instrumentação , Reabilitação do Acidente Vascular Cerebral/métodos , Análise da Marcha/métodos
14.
Molecules ; 29(10)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38792108

RESUMO

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.

15.
BMC Genomics ; 24(1): 163, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37013486

RESUMO

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.


Assuntos
Odontogênese , Dente , Camundongos , Animais , Epitélio/metabolismo , Odontogênese/genética , Proteoglicanas/genética , Proteoglicanas/metabolismo , Transdução de Sinais , Glicosaminoglicanos/metabolismo
16.
J Am Chem Soc ; 145(16): 9112-9117, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37058550

RESUMO

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.

17.
BMC Cardiovasc Disord ; 23(1): 270, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37221473

RESUMO

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.


Assuntos
Sistema Cardiovascular , Hipertensão , Adulto , Idoso , Feminino , Masculino , Humanos , Estudos de Coortes , China , Fatores Etários
18.
Nature ; 547(7662): 232-235, 2017 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-28703188

RESUMO

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.


Assuntos
Alelos , Montagem e Desmontagem da Cromatina/genética , Cromatina/química , Cromatina/genética , Cromossomos de Mamíferos/química , Cromossomos de Mamíferos/genética , Desenvolvimento Embrionário/genética , Animais , Blastocisto/metabolismo , Cromatina/metabolismo , Cromossomos de Mamíferos/metabolismo , Feminino , Fertilização , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Camundongos , Transcrição Gênica , Zigoto/metabolismo
19.
Environ Res ; 220: 115172, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36584849

RESUMO

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.


Assuntos
Poluentes do Solo , Urânio , Fósforo , Fertilizantes/análise , Poluentes do Solo/análise , Solo
20.
Appl Microbiol Biotechnol ; 107(2-3): 553-567, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36517545

RESUMO

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.


Assuntos
Mamíferos , Oligonucleotídeos , Animais , Proteínas Recombinantes/genética , Linhagem Celular
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