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1.
EMBO J ; 42(9): e111762, 2023 05 02.
Article in English | MEDLINE | ID: mdl-36943004

ABSTRACT

Senescence and altered differentiation potential of bone marrow stromal cells (BMSCs) lead to age-related bone loss. As an important posttranscriptional regulatory pathway, alternative splicing (AS) regulates the diversity of gene expression and has been linked to induction of cellular senescence. However, the role of splicing factors in BMSCs during aging remains poorly defined. Herein, we found that the expression of the splicing factor Y-box binding protein 1 (YBX1) in BMSCs decreased with aging in mice and humans. YBX1 deficiency resulted in mis-splicing in genes linked to BMSC osteogenic differentiation and senescence, such as Fn1, Nrp2, Sirt2, Sp7, and Spp1, thus contributing to BMSC senescence and differentiation shift during aging. Deletion of Ybx1 in BMSCs accelerated bone loss in mice, while its overexpression stimulated bone formation. Finally, we identified a small compound, sciadopitysin, which attenuated the degradation of YBX1 and bone loss in old mice. Our study demonstrated that YBX1 governs cell fate of BMSCs via fine control of RNA splicing and provides a potential therapeutic target for age-related osteoporosis.


Subject(s)
Mesenchymal Stem Cells , Osteoporosis , Humans , Mice , Animals , Osteogenesis/genetics , Aging/metabolism , Cellular Senescence , Cell Differentiation/genetics , Osteoporosis/metabolism , Bone Marrow Cells , Y-Box-Binding Protein 1/metabolism
2.
Plant Cell ; 35(11): 4133-4154, 2023 Oct 30.
Article in English | MEDLINE | ID: mdl-37542517

ABSTRACT

Phytohormones play indispensable roles in plant growth and development. However, the molecular mechanisms underlying phytohormone-mediated regulation of fiber secondary cell wall (SCW) formation in cotton (Gossypium hirsutum) remain largely underexplored. Here, we provide mechanistic evidence for functional interplay between the APETALA2/ethylene response factor (AP2/ERF) transcription factor GhERF108 and auxin response factors GhARF7-1 and GhARF7-2 in dictating the ethylene-auxin signaling crosstalk that regulates fiber SCW biosynthesis. Specifically, in vitro cotton ovule culture revealed that ethylene and auxin promote fiber SCW deposition. GhERF108 RNA interference (RNAi) cotton displayed remarkably reduced cell wall thickness compared with controls. GhERF108 interacted with GhARF7-1 and GhARF7-2 to enhance the activation of the MYB transcription factor gene GhMYBL1 (MYB domain-like protein 1) in fibers. GhARF7-1 and GhARF7-2 respond to auxin signals that promote fiber SCW thickening. GhMYBL1 RNAi and GhARF7-1 and GhARF7-2 virus-induced gene silencing (VIGS) cotton displayed similar defects in fiber SCW formation as GhERF108 RNAi cotton. Moreover, the ethylene and auxin responses were reduced in GhMYBL1 RNAi plants. GhMYBL1 directly binds to the promoters of GhCesA4-1, GhCesA4-2, and GhCesA8-1 and activates their expression to promote cellulose biosynthesis, thereby boosting fiber SCW formation. Collectively, our findings demonstrate that the collaboration between GhERF108 and GhARF7-1 or GhARF7-2 establishes ethylene-auxin signaling crosstalk to activate GhMYBL1, ultimately leading to the activation of fiber SCW biosynthesis.


Subject(s)
Cotton Fiber , Transcription Factors , Transcription Factors/genetics , Transcription Factors/metabolism , Indoleacetic Acids/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Gene Expression Regulation, Plant , Gossypium/genetics , Gossypium/metabolism , Plant Growth Regulators/metabolism , Ethylenes/metabolism , Cell Wall/metabolism
3.
Plant J ; 118(2): 423-436, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38184843

ABSTRACT

Upland cotton, the mainly cultivated cotton species in the world, provides over 90% of natural raw materials (fibers) for the textile industry. The development of cotton fibers that are unicellular and highly elongated trichomes on seeds is a delicate and complex process. However, the regulatory mechanism of fiber development is still largely unclear in detail. In this study, we report that a homeodomain-leucine zipper (HD-ZIP) IV transcription factor, GhHOX4, plays an important role in fiber elongation. Overexpression of GhHOX4 in cotton resulted in longer fibers, while GhHOX4-silenced transgenic cotton displayed a "shorter fiber" phenotype compared with wild type. GhHOX4 directly activates two target genes, GhEXLB1D and GhXTH2D, for promoting fiber elongation. On the other hand, phosphatidic acid (PA), which is associated with cell signaling and metabolism, interacts with GhHOX4 to hinder fiber elongation. The basic amino acids KR-R-R in START domain of GhHOX4 protein are essential for its binding to PA that could alter the nuclear localization of GhHOX4 protein, thereby suppressing the transcriptional regulation of GhHOX4 to downstream genes in the transition from fiber elongation to secondary cell wall (SCW) thickening during fiber development. Thus, our data revealed that GhHOX4 positively regulates fiber elongation, while PA may function in the phase transition from fiber elongation to SCW formation by negatively modulating GhHOX4 in cotton.


Subject(s)
Gossypium , Transcription Factors , Gossypium/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Phosphatidic Acids/metabolism , Cotton Fiber , Gene Expression Regulation , Gene Expression Regulation, Plant , Plant Proteins/genetics , Plant Proteins/metabolism
4.
PLoS Pathog ; 19(8): e1011580, 2023 08.
Article in English | MEDLINE | ID: mdl-37566637

ABSTRACT

The multigene family genes (MGFs) in the left variable region (LVR) of the African swine fever virus (ASFV) genome have been reported to be involved in viral replication in primary porcine alveolar macrophages (PAMs) and virulence in pigs. However, the exact functions of key MGFs in the LVR that regulate the replication and virulence of ASFV remain unclear. In this study, we identified the MGF300-2R gene to be critical for viral replication in PAMs by deleting different sets of MGFs in the LVR from the highly virulent strain ASFV HLJ/18 (ASFV-WT). The ASFV mutant lacking the MGF300-2R gene (Del2R) showed a 1-log reduction in viral titer, and induced higher IL-1ß and TNF-α production in PAMs than did ASFV-WT. Mechanistically, the MGF300-2R protein was found to interact with and degrade IKKα and IKKß via the selective autophagy pathway. Furthermore, we showed that MGF300-2R promoted the K27-linked polyubiquitination of IKKα and IKKß, which subsequently served as a recognition signal for the cargo receptor TOLLIP-mediated selective autophagic degradation. Importantly, Del2R exhibited a significant reduction in both replication and virulence compared with ASFV-WT in pigs, likely due to the increased IL-1ß and TNF-α, indicating that MGF300-2R is a virulence determinant. These findings reveal that MGF300-2R suppresses host innate immune responses by mediating the degradation of IKKα and IKKß, which provides clues to paving the way for the rational design of live attenuated vaccines to control ASF.


Subject(s)
African Swine Fever Virus , African Swine Fever , Swine , Animals , African Swine Fever Virus/genetics , Virulence , I-kappa B Kinase/genetics , I-kappa B Kinase/metabolism , Tumor Necrosis Factor-alpha/metabolism , Macrophages , Protein Serine-Threonine Kinases/metabolism , Autophagy
5.
Mol Biol Evol ; 40(5)2023 05 02.
Article in English | MEDLINE | ID: mdl-37134013

ABSTRACT

HIV-1 is a highly host-specific retrovirus that infects humans but not most nonhuman primates. Thus, the lack of a suitable primate model that can be directly infected with HIV-1 hinders HIV-1/AIDS research. In the previous study, we have found that the northern pig-tailed macaques (NPMs) are susceptible to HIV-1 infection but show a nonpathogenic state. In this study, to understand this macaque-HIV-1 interaction, we assembled a de novo genome and longitudinal transcriptome for this species during the course of HIV-1 infection. Using comparative genomic analysis, a positively selected gene, Toll-like receptor 8, was identified with a weak ability to induce an inflammatory response in this macaque. In addition, an interferon-stimulated gene, interferon alpha inducible protein 27, was upregulated in acute HIV-1 infection and acquired an enhanced ability to inhibit HIV-1 replication compared with its human ortholog. These findings coincide with the observation of persistently downregulated immune activation and low viral replication and can partially explain the AIDS-free state in this macaque following HIV-1 infection. This study identified a number of unexplored host genes that may hamper HIV-1 replication and pathogenicity in NPMs and provided new insights into the host defense mechanisms in cross-species infection of HIV-1. This work will facilitate the adoption of NPM as a feasible animal model for HIV-1/AIDS research.


Subject(s)
HIV Infections , HIV-1 , Simian Immunodeficiency Virus , Animals , Humans , Macaca nemestrina , HIV-1/genetics , Genomics , Simian Immunodeficiency Virus/genetics
6.
Eur J Immunol ; 53(4): e2250204, 2023 04.
Article in English | MEDLINE | ID: mdl-36681386

ABSTRACT

Tuberculosis caused by Mycobacterium tuberculosis (M.tb) is one of the main causes of human death in the world. Bacillus Calmette-Guérin (BCG) provides limited protection in adolescents and adults. To explore the factors reducing efficacy of BCG vaccine, we assess the impacts of interleukin (IL)-10 and alarmins S100A8/A9 on T-cell memory. We found that BCG-induced IL-10 inhibited production of S100A8/A9 in human peripheral blood mononuclear cells (PBMCs) and murine splenocytes. S100A9 deficiency inhibited IFN-γ production by CD4+ T cells in the early phase of BCG immunization and hindered the development of effector memory T helper type 1 (Th1) cells, while IL-10 deficiency promoted Th1 memory and blocking IL-10 signaling enhanced Th1 protective recall response against M.tb. IL-10 inhibited the binding of transcription factor CCAAT enhancer binding protein beta to S100a8/a9 promoter leading to S100A8/A9 reduction. S100A8/A9 heterodimer enhanced the IFN-γ production via receptor for advanced glycation end products signaling in CD4+ T cells. Our results demonstrate a hurdle to development of Th1 memory after BCG immunization and clarify the mechanism of the regulation of Th1 memory by IL-10 and S100A8/A9.


Subject(s)
Mycobacterium bovis , Tuberculosis , Adolescent , Adult , Animals , Humans , Mice , BCG Vaccine , Interleukin-10 , Leukocytes, Mononuclear , Th1 Cells/immunology
7.
Biochem Biophys Res Commun ; 706: 149766, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38484568

ABSTRACT

Secretory myeloid-derived growth factor (MYDGF) exerts beneficial effects on organ repair, probably via a plasma membrane receptor; however, the identity of the expected receptor has remained elusive. In a recent study, MYDGF was reported as an agonist of the sphingosine-1-phosphate receptor 2 (S1PR2), an A-class G protein-coupled receptor that mediates the functions of the signaling lipid, sphingosine-1-phosphate (S1P). In the present study, we conducted living cell-based functional assays to test whether S1PR2 is a receptor for MYDGF. In the NanoLuc Binary Technology (NanoBiT)-based ß-arrestin recruitment assay and the cAMP-response element (CRE)-controlled NanoLuc reporter assay, S1P could efficiently activate human S1PR2 overexpressed in human embryonic kidney (HEK) 293T cells; however, recombinant human MYDGF, overexpressed either from Escherichia coli or HEK293 cells, had no detectable effect. Thus, the results demonstrated that human MYDGF is not a ligand of human S1PR2. Considering the high conservation of MYDGF and S1PR2 in evolution, MYDGF is also probably not a ligand of S1PR2 in other vertebrates.


Subject(s)
Granulocyte Colony-Stimulating Factor , Receptors, Lysosphingolipid , Sphingosine/analogs & derivatives , Animals , Humans , Sphingosine-1-Phosphate Receptors , Receptors, Lysosphingolipid/genetics , Receptors, Lysosphingolipid/metabolism , Ligands , HEK293 Cells , Lysophospholipids/pharmacology
8.
Am Heart J ; 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38942221

ABSTRACT

BACKGROUND: It is currently uncertain whether the combination of a proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor and high-intensity statin treatment can effectively reduce cardiovascular events in patients with acute coronary syndrome (ACS) who have undergone percutaneous coronary intervention (PCI) for culprit lesions. METHODS: This study protocol describes a double-blind, randomized, placebo-controlled, multicenter study aiming to investigate the efficacy and safety of combining a PCSK9 inhibitor with high-intensity statin therapy in patients with ACS following PCI. A total of 1212 patients with ACS and multiple lesions will be enrolled and randomly assigned to receive either PCSK9 inhibitor plus high-intensity statin therapy or high-intensity statin monotherapy. The randomization process will be stratified by sites, diabetes, initial presentation and use of stable (≥4 weeks) statin treatment at presentation. PCSK 9 inhibitor or its placebo is injected within 4 hours after PCI for the culprit lesion. The primary endpoint is the composite of cardiovascular death, myocardial infarction, stroke, re-hospitalization due to ACS or heart failure, or any ischemia-driven coronary revascularization at one-year follow-up between two groups. Safety endpoints mean PCSK 9 inhibitor and statin intolerance. CONCLUSION: The SHAWN study has been specifically designed to evaluate the effectiveness and safety of adding a PCSK9 inhibitor to high-intensity statin therapy in patients who have experienced ACS following PCI. The primary objective of this study is to generate new evidence regarding the potential benefits of combining a PCSK9 inhibitor with high-intensity statin treatment in reducing cardiovascular events among these patients.

9.
Chembiochem ; : e202400269, 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38923255

ABSTRACT

The human malaria parasite Plasmodium falciparum (P. falciparum) continues to pose a significant public health challenge, leading to millions of fatalities globally. Halofuginone (HF) has shown a significant anti-P. falciparum effect, suggesting its potential as a therapeutic agent for malaria treatment. In this study, we synthesized a photoaffinity labeling probe of HF to identify its direct target in P. falciparum. Our results reveal that ubiquitin carboxyl-terminal hydrolase 3 (PfUCHL3) acts as a crucial target protein of HF, which modulates parasite growth in the intraerythrocytic cycle. In particular, we discovered that HF potentially forms hydrogen bonds with the Leu10, Glu11, and Arg217 sites of PfUCHL3, thereby inducing an allosteric effect by promoting the embedding of the helix 6' region on the protein surface. Furthermore, HF disrupts the expression of multiple functional proteins mediated by PfUCHL3, specifically those that play crucial roles in amino acid biosynthesis and metabolism in P. falciparum. Taken together, this study highlights PfUCHL3 as a previously undisclosed druggable target of HF, which contributes to the development of novel anti-malarial agents in the future.

10.
J Virol ; 97(4): e0020023, 2023 04 27.
Article in English | MEDLINE | ID: mdl-36971578

ABSTRACT

Tetherin prevents viral cross-species transmission by inhibiting the release of multiple enveloped viruses from infected cells. With the evolution of simian immunodeficiency virus of chimpanzees (SIVcpz), a pandemic human immunodeficiency virus type 1 (HIV-1) precursor, its Vpu protein can antagonize human tetherin (hTetherin). Macaca leonina (northern pig-tailed macaque [NPM]) is susceptible to HIV-1, but host-specific restriction factors limit virus replication in vivo. In this study, we isolated the virus from NPMs infected with strain stHIV-1sv (with a macaque-adapted HIV-1 env gene from simian-human immunodeficiency virus SHIV-KB9, a vif gene replaced by SIVmac239, and other genes originating from HIV-1NL4.3) and found that a single acidic amino acid substitution (G53D) in Vpu could increase its ability to degrade the tetherin of macaques (mTetherin) mainly through the proteasome pathway, resulting in an enhanced release and resistance to interferon inhibition of the mutant stHIV-1sv strain, with no influence on the other functions of Vpu. IMPORTANCE HIV-1 has obvious host specificity, which has greatly hindered the construction of animal models and severely restricted the development of HIV-1 vaccines and drugs. To overcome this barrier, we attempted to isolate the virus from NPMs infected with stHIV-1sv, search for a strain with an adaptive mutation in NPMs, and develop a more appropriate nonhuman primate model of HIV-1. This is the first report identifying HIV-1 adaptations in NPMs. It suggests that while tetherin may limit HIV-1 cross-species transmission, the Vpu protein in HIV-1 can overcome this species barrier through adaptive mutation, increasing viral replication in the new host. This finding will be beneficial to building an appropriate animal model for HIV-1 infection and promoting the development of HIV-1 vaccines and drugs.


Subject(s)
Bone Marrow Stromal Antigen 2 , HIV-1 , Macaca , Viral Proteins , Virus Release , HIV-1/genetics , HIV-1/pathogenicity , Viral Proteins/genetics , Viral Proteins/metabolism , Mutation , Bone Marrow Stromal Antigen 2/metabolism , Ubiquitin/metabolism , Proteasome Endopeptidase Complex/metabolism , Virus Release/genetics , Amino Acid Substitution/genetics , HIV Infections/virology , Disease Models, Animal , Virus Replication/genetics
11.
J Med Virol ; 96(1): e29396, 2024 01.
Article in English | MEDLINE | ID: mdl-38235848

ABSTRACT

The RNA-dependent RNA polymerase (RdRp) is a crucial element in the replication and transcription of RNA viruses. Although the RdRps of lethal human coronaviruses severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), SARS-CoV, and Middle East respiratory syndrome coronavirus (MERS-CoV) have been extensively studied, the molecular mechanism of the catalytic subunit NSP12, which is involved in pathogenesis, remains unclear. In this study, the biochemical and cell biological results demonstrate the interactions between SARS-CoV-2 NSP12 and seven host proteins, including three splicing factors (SLU7, PPIL3, and AKAP8). The entry efficacy of SARS-CoV-2 considerably decreased when SLU7 or PPIL3 was knocked out, indicating that abnormal splicing of the host genome was responsible for this occurrence. Furthermore, the polymerase activity and stability of SARS-CoV-2 RdRp were affected by the three splicing factors to varying degrees. In addition, NSP12 and its homologues from SARS-CoV and MERS-CoV suppressed the alternative splicing of cellular genes, which were influenced by the three splicing factors. Overall, our research illustrates that SARS-CoV-2 NSP12 can engage with various splicing factors, thereby impacting virus entry, replication, and gene splicing. This not only improves our understanding of how viruses cause diseases but also lays the foundation for the development of antiviral therapies.


Subject(s)
COVID-19 , Middle East Respiratory Syndrome Coronavirus , Humans , SARS-CoV-2/genetics , SARS-CoV-2/metabolism , COVID-19/genetics , RNA-Dependent RNA Polymerase/metabolism , Middle East Respiratory Syndrome Coronavirus/genetics , RNA Splicing Factors
12.
Plant Cell ; 33(8): 2736-2752, 2021 08 31.
Article in English | MEDLINE | ID: mdl-34043792

ABSTRACT

Cotton, one of the most important crops in the world, produces natural fiber materials for the textile industry. WRKY transcription factors play important roles in plant development and stress responses. However, little is known about whether and how WRKY transcription factors regulate fiber development of cotton so far. In this study, we show that a fiber-preferential WRKY transcription factor, GhWRKY16, positively regulates fiber initiation and elongation. GhWRKY16-silenced transgenic cotton displayed a remarkably reduced number of fiber protrusions on the ovule and shorter fibers compared to the wild-type. During early fiber development, GhWRKY16 directly binds to the promoters of GhHOX3, GhMYB109, GhCesA6D-D11, and GhMYB25 to induce their expression, thereby promoting fiber initiation and elongation. Moreover, GhWRKY16 is phosphorylated by the mitogen-activated protein kinase GhMPK3-1 at residues T-130 and S-260. Phosphorylated GhWRKY16 directly activates the transcription of GhMYB25, GhHOX3, GhMYB109, and GhCesA6D-D11 for early fiber development. Thus, our data demonstrate that GhWRKY16 plays a crucial role in fiber initiation and elongation, and that GhWRKY16 phosphorylation by GhMPK3-1 is essential for the transcriptional activation on downstream genes during the fiber development of cotton.


Subject(s)
Cotton Fiber , Gossypium/physiology , Plant Proteins/metabolism , Transcription Factors/metabolism , Gene Expression Regulation, Plant , Ovule/growth & development , Phosphorylation , Plant Proteins/genetics , Plants, Genetically Modified , Promoter Regions, Genetic , Transcription Factors/genetics
13.
J Org Chem ; 89(12): 9031-9042, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38829824

ABSTRACT

A cooperative Rh/achiral phosphoric acid-enabled [3+3] cycloaddition of in situ-generated carbonyl ylides with quinone monoimines has been developed. With the ability to build up the molecular complexity rapidly and efficiently, this method furnishes highly functionalized oxa-bridged benzofused dioxabicyclo[3.2.1]octane scaffolds bearing two quaternary centers in good to excellent yields under mild conditions. Moreover, the utility of the current method was demonstrated by gram-scale synthesis and elaboration of the products into various functionalized oxa-bridged heterocycles.

14.
J Fluoresc ; 2024 Jan 09.
Article in English | MEDLINE | ID: mdl-38193953

ABSTRACT

A fluorescent Fe3+ probe ((C10H7NO2)2B18H20, M1) by introducing two isoquinoline-1-carboxylic acid group into the 6,9-position of anti-B18H22 was designed and synthesized. The structure of M1 was investigated by 1H NMR, MS, FT-IR and theoretical calculation, and its optical properties were characterized with UV-Vis and PL. M1 showed aggregation induced emission enhancement (AIEE) properties in THF/H2O solution, and exhibited an excellent selectivity toward Fe3+ in THF/H2O (v/v, ƒw = 95%) solution with a detection limit of 1.93 × 10-5 M. The interaction mechanism of probe for detecting Fe3+ is attributed to the involvement of intramolecular charge transfer (ICT) process. Furthermore, a optical fiber fluorescent Fe3+ sensor based on M1 sensing film was developed, the detection limit of the optical fiber Fe3+ fluorescent sensor could be improved to13.8 pM, the ultra-low detection limit is superior to most reported fluorescent probes (or sensors) towards Fe3+. This method has the advantages of high sensitivity, anti-interference and easy to operate, and has great potential in the field of the analysis of environmental and biological samples.

15.
Macromol Rapid Commun ; 45(4): e2300568, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37956305

ABSTRACT

Fibrous strain sensing materials with both high sensitivity and high linearity are of significant importance for wearable sensors, yet they still face great challenges. Herein, a photo-spun reaction encapsulation strategy is proposed for the continuous fabrication of fibrous strain sensor materials (AMGF) with a core-sheath structure. Metallogels (MOGs) formed by bacterial cellulose (BC) nanofibers and Ag nanoparticles (AgNPs), and thermoplastic elastomers (TPE) are employed as the core and sheath, respectively. The in situ ultraviolet light reduction of Ag+ ensured AgNPs to maintain the interconnections between the BC nanofibers and form electron conductive networks (0.31 S m-1 ). Under applied strain, the BC nanofibers experience separation, bringing AMGF a high sensitivity (gauge factor 4.36). The concentration of free ions in the MOGs uniformly varies with applied deformation, endowing AMGF with high linearity and a goodness-of-fit of 0.98. The sheath TPE provided AMGF sensor with stable working life (>10 000 s). Furthermore, the AMGF sensors are demonstrated to monitor complex deformations of the dummy joints in real-time as a wearable sensor. Therefore, the fibrous hybrid conductive network fibers fabricated via the photo-spun reaction encapsulation strategy provide a new route for addressing the challenge of achieving both high sensitivity and high linearity.


Subject(s)
Metal Nanoparticles , Wearable Electronic Devices , Metal Nanoparticles/chemistry , Electrons , Silver/chemistry , Elastomers/chemistry
16.
Br J Anaesth ; 2024 Mar 24.
Article in English | MEDLINE | ID: mdl-38527923

ABSTRACT

BACKGROUND: Numerous models have been developed to predict acute kidney injury (AKI) after noncardiac surgery, yet there is a lack of independent validation and comparison among them. METHODS: We conducted a systematic literature search to review published risk prediction models for AKI after noncardiac surgery. An independent external validation was performed using a retrospective surgical cohort at a large Chinese hospital from January 2019 to October 2022. The cohort included patients undergoing a wide range of noncardiac surgeries with perioperative creatinine measurements. Postoperative AKI was defined according to the Kidney Disease Improving Global Outcomes creatinine criteria. Model performance was assessed in terms of discrimination (area under the receiver operating characteristic curve, AUROC), calibration (calibration plot), and clinical utility (net benefit), before and after model recalibration through intercept and slope updates. A sensitivity analysis was conducted by including patients without postoperative creatinine measurements in the validation cohort and categorising them as non-AKI cases. RESULTS: Nine prediction models were evaluated, each with varying clinical and methodological characteristics, including the types of surgical cohorts used for model development, AKI definitions, and predictors. In the validation cohort involving 13,186 patients, 650 (4.9%) developed AKI. Three models demonstrated fair discrimination (AUROC between 0.71 and 0.75); other models had poor or failed discrimination. All models exhibited some miscalibration; five of the nine models were well-calibrated after intercept and slope updates. Decision curve analysis indicated that the three models with fair discrimination consistently provided a positive net benefit after recalibration. The results were confirmed in the sensitivity analysis. CONCLUSIONS: We identified three models with fair discrimination and potential clinical utility after recalibration for assessing the risk of acute kidney injury after noncardiac surgery.

17.
Nature ; 564(7734): 136-140, 2018 12.
Article in English | MEDLINE | ID: mdl-30487604

ABSTRACT

Postnatal growth of mammalian oocytes is accompanied by a progressive gain of DNA methylation, which is predominantly mediated by DNMT3A, a de novo DNA methyltransferase1,2. Unlike the genome of sperm and most somatic cells, the oocyte genome is hypomethylated in transcriptionally inert regions2-4. However, how such a unique feature of the oocyte methylome is determined and its contribution to the developmental competence of the early embryo remains largely unknown. Here we demonstrate the importance of Stella, a factor essential for female fertility5-7, in shaping the oocyte methylome in mice. Oocytes that lack Stella acquire excessive DNA methylation at the genome-wide level, including in the promoters of inactive genes. Such aberrant hypermethylation is partially inherited by two-cell-stage embryos and impairs zygotic genome activation. Mechanistically, the loss of Stella leads to ectopic nuclear accumulation of the DNA methylation regulator UHRF18,9, which results in the mislocalization of maintenance DNA methyltransferase DNMT1 in the nucleus. Genetic analysis confirmed the primary role of UHRF1 and DNMT1 in generating the aberrant DNA methylome in Stella-deficient oocytes. Stella therefore safeguards the unique oocyte epigenome by preventing aberrant de novo DNA methylation mediated by DNMT1 and UHRF1.


Subject(s)
DNA (Cytosine-5-)-Methyltransferase 1/metabolism , DNA Methylation , Epigenesis, Genetic , Oocytes/metabolism , Repressor Proteins/metabolism , Animals , CCAAT-Enhancer-Binding Proteins , Cell Line , Cell Nucleus/metabolism , Chromosomal Proteins, Non-Histone , DNA (Cytosine-5-)-Methyltransferase 1/antagonists & inhibitors , Embryonic Development , Female , Genome/genetics , Humans , Mice , Nuclear Proteins/metabolism , Promoter Regions, Genetic/genetics , Repressor Proteins/deficiency , Repressor Proteins/genetics , Ubiquitin-Protein Ligases , Zygote/metabolism
18.
Mol Cell ; 64(5): 913-925, 2016 12 01.
Article in English | MEDLINE | ID: mdl-27840027

ABSTRACT

TET family enzymes successively oxidize 5-methylcytosine to 5-hydroxymethylcytosine, 5-formylcytosine, and 5-carboxylcytosine, leading to eventual demethylation. 5hmC and TET enzymes occupy distinct chromatin regions, suggesting unknown mechanisms controlling the fate of 5hmC within diverse chromatin environments. Here, we report that SALL4A preferentially associates with 5hmC in vitro and occupies enhancers in mouse embryonic stem cells in a largely TET1-dependent manner. Although most 5hmC at SALL4A peaks undergoes further oxidation, this process is abrogated upon deletion of Sall4 gene, with a concomitant reduction of TET2 at these regions. Thus, SALL4A facilitates further oxidation of 5hmC at its binding sites, which requires its 5hmC-binding activity and TET2, supporting a collaborative action between SALL4A and TET proteins in regulating stepwise oxidation of 5mC at enhancers. Our study identifies SALL4A as a 5hmC binder, which facilitates 5hmC oxidation by stabilizing TET2 association, thereby fine-tuning expression profiles of developmental genes in mouse embryonic stem cells.


Subject(s)
5-Methylcytosine/metabolism , DNA-Binding Proteins/metabolism , Embryonic Stem Cells/metabolism , Transcription Factors/metabolism , Animals , DNA Methylation , Dioxygenases , Enhancer Elements, Genetic/physiology , Mice , Oxidation-Reduction , Proto-Oncogene Proteins/metabolism , Transcription, Genetic
19.
Cell Mol Biol Lett ; 29(1): 50, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38594618

ABSTRACT

BACKGROUND: Melanoma is the most lethal skin cancer characterized by its high metastatic potential. In the past decade, targeted and immunotherapy have brought revolutionary survival benefits to patients with advanced and metastatic melanoma, but these treatment responses are also heterogeneous and/or do not achieve durable responses. Therefore, novel therapeutic strategies for improving outcomes remain an unmet clinical need. The aim of this study was to evaluate the therapeutic potential and underlying molecular mechanisms of RC48, a novel HER2-target antibody drug conjugate, either alone or in combination with dabrafenib, a V600-mutant BRAF inhibitor, for the treatment of advanced BRAF-mutant cutaneous melanoma. METHODS: We evaluated the therapeutic efficacy of RC48, alone or in combination with dabrafenib, in BRAF-mutant cutaneous melanoma cell lines and cell-derived xenograft (CDX) models. We also conducted signaling pathways analysis and global mRNA sequencing to explore mechanisms underlying the synergistic effect of the combination therapy. RESULTS: Our results revealed the expression of membrane-localized HER2 in melanoma cells. RC48 effectively targeted and inhibited the growth of HER2-positive human melanoma cell lines and corresponding CDX models. When used RC48 and dabrafenib synergically induced tumor regression together in human BRAF-mutant melanoma cell lines and CDX models. Mechanically, our results demonstrated that the combination therapy induced apoptosis and cell cycle arrest while suppressing cell motility in vitro. Furthermore, global RNA sequencing analysis demonstrated that the combination treatment led to the downregulation of several key signaling pathways, including the PI3K-AKT pathway, MAPK pathway, AMPK pathway, and FOXO pathway. CONCLUSION: These findings establish a preclinical foundation for the combined use of an anti-HER2 drug conjugate and a BRAF inhibitor in the treatment of BRAF-mutant cutaneous melanoma.


Subject(s)
Antineoplastic Agents , Imidazoles , Immunoconjugates , Melanoma , Oximes , Skin Neoplasms , Humans , Melanoma/drug therapy , Melanoma/genetics , Skin Neoplasms/genetics , Proto-Oncogene Proteins B-raf/genetics , Proto-Oncogene Proteins B-raf/metabolism , Phosphatidylinositol 3-Kinases , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Immunoconjugates/genetics , Immunoconjugates/therapeutic use , Mutation
20.
BMC Musculoskelet Disord ; 25(1): 191, 2024 Mar 02.
Article in English | MEDLINE | ID: mdl-38431558

ABSTRACT

BACKGROUND: Plantar fasciitis (PF) is the most common cause of heel pain. Among conservative treatments, extracorporeal shock wave therapy (ESWT) is considered effective for refractory PF. Studies have shown that applying ESWT to the trigger points (TrPs) in the triceps surae may play an important role in pain treatment in patients with PF. Therefore, the purpose of this study was to combine the concept of trigger points and ESWT to explore the effect of this combination on plantar temperature and pressure in patients with PF. METHODS: After applying inclusion and exclusion criteria, 86 patients with PF were recruited from the pain clinic of Huadong Hospital, Fudan University and randomly divided into experimental (n = 43) and control groups (n = 43). The experimental group was treated with extracorporeal shock waves to treat the medial heel pain point and the gastrocnemius and soleus TrPs. The control group was only treated with extracorporeal shock waves at the medial heel pain point. The two groups were treated twice with an interval of 1 week. Primary measurements included a numerical rating scale (NRS) score (overall, first step, heel pain during daily activities), and secondary measurements included heel temperature, Roles-Maudsley score (RMS), and plantar pressure. All assessments were performed before treatment (i.e., baseline) and 6 and 12 weeks after treatment. RESULTS: During the trial, 3 patients in the experimental group withdrew from the study, 2 due to interruption of the course of treatment by the COVID-19 epidemic and 1 due to personal reasons. In the control group, 3 patients fell and were removed due to swelling of the heel. Therefore, only 80 patients with PF were finally included. After treatment, the two groups showed good results in NRS score (overall, first step, heel pain during daily activities), RMS, and plantar temperature, especially in the experimental group, who showed a significantly better effect than the control group. CONCLUSION: ESWT of the heel combined with the triceps trigger point of the calf can more effectively improve the pain, function and quality of life of refractory PF than ESWT of the heel alone. In addition, ESWT of the heel combined with the triceps trigger point of the calf can effectively reduce the skin temperature of the heel on the symptomatic side, indicating that the heel temperature as measured by infrared thermal imaging may be used as an independent tool to evaluate the therapeutic effect for patients with chronic PF. Although extracorporeal shock waves combined with TrPs treatment can cause changes in the patients' gait structure, plantar pressure is still difficult to use as an independent tool to evaluate the therapeutic effect for PF. TRIAL REGISTRATION: Registered in the Chinese Clinical Trial Registry ( www.chictr.org.cn ) on 12/17/2021 with the following code: ChiCTR-INR-2,100,054,439.


Subject(s)
Fasciitis, Plantar , Humans , Fasciitis, Plantar/complications , Heel , Trigger Points , Quality of Life , Temperature , Treatment Outcome , Pain/etiology
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