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1.
Nature ; 616(7955): 56-60, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36949191

RESUMO

Quantum error correction (QEC) aims to protect logical qubits from noises by using the redundancy of a large Hilbert space, which allows errors to be detected and corrected in real time1. In most QEC codes2-8, a logical qubit is encoded in some discrete variables, for example photon numbers, so that the encoded quantum information can be unambiguously extracted after processing. Over the past decade, repetitive QEC has been demonstrated with various discrete-variable-encoded scenarios9-17. However, extending the lifetimes of thus-encoded logical qubits beyond the best available physical qubit still remains elusive, which represents a break-even point for judging the practical usefulness of QEC. Here we demonstrate a QEC procedure in a circuit quantum electrodynamics architecture18, where the logical qubit is binomially encoded in photon-number states of a microwave cavity8, dispersively coupled to an auxiliary superconducting qubit. By applying a pulse featuring a tailored frequency comb to the auxiliary qubit, we can repetitively extract the error syndrome with high fidelity and perform error correction with feedback control accordingly, thereby exceeding the break-even point by about 16% lifetime enhancement. Our work illustrates the potential of hardware-efficient discrete-variable encodings for fault-tolerant quantum computation19.

2.
Development ; 151(6)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38546043

RESUMO

The timely degradation of proteins that regulate the cell cycle is essential for oocyte maturation. Oocytes are equipped to degrade proteins via the ubiquitin-proteasome system. In meiosis, anaphase promoting complex/cyclosome (APC/C), an E3 ubiquitin-ligase, is responsible for the degradation of proteins. Ubiquitin-conjugating enzyme E2 S (UBE2S), an E2 ubiquitin-conjugating enzyme, delivers ubiquitin to APC/C. APC/C has been extensively studied, but the functions of UBE2S in oocyte maturation and mouse fertility are not clear. In this study, we used Ube2s knockout mice to explore the role of UBE2S in mouse oocytes. Ube2s-deleted oocytes were characterized by meiosis I arrest with normal spindle assembly and spindle assembly checkpoint dynamics. However, the absence of UBE2S affected the activity of APC/C. Cyclin B1 and securin are two substrates of APC/C, and their levels were consistently high, resulting in the failure of homologous chromosome separation. Unexpectedly, the oocytes arrested in meiosis I could be fertilized and the embryos could become implanted normally, but died before embryonic day 10.5. In conclusion, our findings reveal an indispensable regulatory role of UBE2S in mouse oocyte meiosis and female fertility.


Assuntos
Pontos de Checagem da Fase M do Ciclo Celular , Meiose , Animais , Feminino , Camundongos , Ciclossomo-Complexo Promotor de Anáfase/genética , Ciclossomo-Complexo Promotor de Anáfase/metabolismo , Oócitos/metabolismo , Ubiquitinas/metabolismo
3.
Proc Natl Acad Sci U S A ; 121(34): e2322938121, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39141351

RESUMO

The removal of mis-incorporated nucleotides by proofreading activity ensures DNA replication fidelity. Whereas the ε-exonuclease DnaQ is a well-established proofreader in the model organism Escherichia coli, it has been shown that proofreading in a majority of bacteria relies on the polymerase and histidinol phosphatase (PHP) domain of replicative polymerase, despite the presence of a DnaQ homolog that is structurally and functionally distinct from E. coli DnaQ. However, the biological functions of this type of noncanonical DnaQ remain unclear. Here, we provide independent evidence that noncanonical DnaQ functions as an additional proofreader for mycobacteria. Using the mutation accumulation assay in combination with whole-genome sequencing, we showed that depletion of DnaQ in Mycolicibacterium smegmatis leads to an increased mutation rate, resulting in AT-biased mutagenesis and increased insertions/deletions in the homopolymer tract. Our results showed that mycobacterial DnaQ binds to the ß clamp and functions synergistically with the PHP domain proofreader to correct replication errors. Furthermore, the loss of dnaQ results in replication fork dysfunction, leading to attenuated growth and increased mutagenesis on subinhibitory fluoroquinolones potentially due to increased vulnerability to fork collapse. By analyzing the sequence polymorphism of dnaQ in clinical isolates of Mycobacterium tuberculosis (Mtb), we demonstrated that a naturally evolved DnaQ variant prevalent in Mtb lineage 4.3 may enable hypermutability and is associated with drug resistance. These results establish a coproofreading model and suggest a division of labor between DnaQ and PHP domain proofreader. This study also provides real-world evidence that a mutator-driven evolutionary pathway may exist during the adaptation of Mtb.


Assuntos
Replicação do DNA , Mycobacterium smegmatis/genética , Mycobacterium smegmatis/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Mutação
4.
Genome Res ; 33(3): 463-477, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-37310928

RESUMO

Structural variations (SVs) are a major contributor to genetic diversity and phenotypic variations, but their prevalence and functions in domestic animals are largely unexplored. Here we generated high-quality genome assemblies for 15 individuals from genetically diverse sheep breeds using Pacific Biosciences (PacBio) high-fidelity sequencing, discovering 130.3 Mb nonreference sequences, from which 588 genes were annotated. A total of 149,158 biallelic insertions/deletions, 6531 divergent alleles, and 14,707 multiallelic variations with precise breakpoints were discovered. The SV spectrum is characterized by an excess of derived insertions compared to deletions (94,422 vs. 33,571), suggesting recent active LINE expansions in sheep. Nearly half of the SVs display low to moderate linkage disequilibrium with surrounding single-nucleotide polymorphisms (SNPs) and most SVs cannot be tagged by SNP probes from the widely used ovine 50K SNP chip. We identified 865 population-stratified SVs including 122 SVs possibly derived in the domestication process among 690 individuals from sheep breeds worldwide. A novel 168-bp insertion in the 5' untranslated region (5' UTR) of HOXB13 is found at high frequency in long-tailed sheep. Further genome-wide association study and gene expression analyses suggest that this mutation is causative for the long-tail trait. In summary, we have developed a panel of high-quality de novo assemblies and present a catalog of structural variations in sheep. Our data capture abundant candidate functional variations that were previously unexplored and provide a fundamental resource for understanding trait biology in sheep.


Assuntos
Estudo de Associação Genômica Ampla , Cauda , Animais , Ovinos/genética , Regiões 5' não Traduzidas , Alelos , Fenótipo
5.
J Immunol ; 212(2): 258-270, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-38079221

RESUMO

Oxidants participate in lymphocyte activation and function. We previously demonstrated that eliminating the activity of NADPH oxidase 2 (NOX2) significantly impaired the effectiveness of autoreactive CD8+ CTLs. However, the molecular mechanisms impacting CD8+ T cell function remain unknown. In the present study, we examined the role of NOX2 in both NOD mouse and human CD8+ T cell function. Genetic ablation or chemical inhibition of NOX2 in CD8+ T cells significantly suppressed activation-induced expression of the transcription factor T-bet, the master transcription factor of the Tc1 cell lineage, and T-bet target effector genes such as IFN-γ and granzyme B. Inhibition of NOX2 in both human and mouse CD8+ T cells prevented target cell lysis. We identified that superoxide generated by NOX2 must be converted into hydrogen peroxide to transduce the redox signal in CD8+ T cells. Furthermore, we show that NOX2-generated oxidants deactivate the tumor suppressor complex leading to activation of RheB and subsequently mTOR complex 1. These results indicate that NOX2 plays a nonredundant role in TCR-mediated CD8+ T cell effector function.


Assuntos
Linfócitos T CD8-Positivos , NADPH Oxidase 2 , Espécies Reativas de Oxigênio , Animais , Humanos , Camundongos , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Citocinas/imunologia , Granzimas/metabolismo , Peróxido de Hidrogênio/metabolismo , Inflamação/imunologia , Interferon gama/metabolismo , Ativação Linfocitária , Camundongos Endogâmicos NOD , NADPH Oxidase 2/antagonistas & inibidores , NADPH Oxidase 2/metabolismo , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais , Proteínas com Domínio T/metabolismo , Masculino , Feminino , Adulto Jovem
6.
Proc Natl Acad Sci U S A ; 120(52): e2311673120, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38109541

RESUMO

The unbalanced immune state is the dominant feature of myocardial injury. However, the complicated pathology of cardiovascular diseases and the unique structure of cardiac tissue lead to challenges for effective immunoregulation therapy. Here, we exploited oral fullerene nanoscavenger (OFNS) to maintain intestinal redox homeostasis to resolve systemic inflammation for effectively preventing distal myocardial injury through bidirectional communication along the heart-gut immune axis. Observably, OFNS regulated redox microenvironment to repair cellular injury and reduce inflammation in vitro. Subsequently, OFNS prevented myocardial injury by regulating intestinal redox homeostasis and recovering epithelium barrier integrity in vivo. Based on the profiles of transcriptomics and proteomics, we demonstrated that OFNS balanced intestinal and systemic immune homeostasis for remote cardioprotection. Of note, we applied this principle to intervene myocardial infarction in mice and mini-pigs. These findings highlight that locally addressing intestinal redox to inhibit systemic inflammation could be a potent strategy for resolving remote tissue injury.


Assuntos
Fulerenos , Infarto do Miocárdio , Suínos , Camundongos , Animais , Fulerenos/farmacologia , Porco Miniatura , Inflamação/patologia , Infarto do Miocárdio/prevenção & controle , Homeostase , Mucosa Intestinal
7.
FASEB J ; 38(10): e23698, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38780613

RESUMO

Prostate cancer (PCa) is a widespread global health concern characterized by elevated rates of occurrence, and there is a need for novel therapeutic targets to enhance patient outcomes. FOXS1 is closely linked to different cancers, but its function in PCa is still unknown. The expression of FOXS1, its prognostic role, clinical significance in PCa, and the potential mechanism by which FOXS1 affects PCa progression were investigated through bioinformatics analysis utilizing public data. The levels of FOXS1 and HILPDA were evaluated in clinical PCa samples using various methods, such as western blotting, immunohistochemistry, and qRT-PCR. To examine the function and molecular mechanisms of FOXS1 in PCa, a combination of experimental techniques including CCK-8 assay, flow cytometry, wound-healing assay, Transwell assay, and Co-IP assay were employed. The FOXS1 expression levels were significantly raised in PCa, correlating strongly with tumor aggressiveness and an unfavorable prognosis. Regulating FOXS1 expression, whether upregulating or downregulating it, correspondingly enhanced or inhibited the growth, migration, and invasion capabilities of PCa cells. Mechanistically, we detected a direct interaction between FOXS1 and HILPDA, resulting in the pathway activation of FAK/PI3K/AKT and facilitation EMT in PCa cells. FOXS1 collaborates with HILPDA to initiate EMT, thereby facilitating the PCa progression through the FAK/PI3K/AKT pathway activation.


Assuntos
Transição Epitelial-Mesenquimal , Fatores de Transcrição Forkhead , Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata , Animais , Humanos , Masculino , Camundongos , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Quinase 1 de Adesão Focal/metabolismo , Quinase 1 de Adesão Focal/genética , Fatores de Transcrição Forkhead/metabolismo , Fatores de Transcrição Forkhead/genética , Camundongos Nus , Oncogenes , Fosfatidilinositol 3-Quinases/metabolismo , Prognóstico , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais , Regulação para Cima , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo
8.
Cell Mol Life Sci ; 81(1): 247, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829550

RESUMO

BACKGROUND: The high degree of intratumoral genomic heterogeneity is a major obstacle for glioblastoma (GBM) tumors, one of the most lethal human malignancies, and is thought to influence conventional therapeutic outcomes negatively. The proneural-to-mesenchymal transition (PMT) of glioma stem cells (GSCs) confers resistance to radiation therapy in glioblastoma patients. POLD4 is associated with cancer progression, while the mechanisms underlying PMT and tumor radiation resistance have remained elusive. METHOD: Expression and prognosis of the POLD family were analyzed in TCGA, the Chinese Glioma Genome Atlas (CGGA) and GEO datasets. Tumorsphere formation and in vitro limiting dilution assay were performed to investigate the effect of UCHL3-POLD4 on GSC self-renewal. Apoptosis, TUNEL, cell cycle phase distribution, modification of the Single Cell Gel Electrophoresis (Comet), γ-H2AX immunofluorescence, and colony formation assays were conducted to evaluate the influence of UCHL3-POLD4 on GSC in ionizing radiation. Coimmunoprecipitation and GST pull-down assays were performed to identify POLD4 protein interactors. In vivo, intracranial xenograft mouse models were used to investigate the molecular effect of UCHL3, POLD4 or TCID on GCS. RESULT: We determined that POLD4 was considerably upregulated in MES-GSCs and was associated with a meagre prognosis. Ubiquitin carboxyl terminal hydrolase L3 (UCHL3), a DUB enzyme in the UCH protease family, is a bona fide deubiquitinase of POLD4 in GSCs. UCHL3 interacted with, depolyubiquitinated, and stabilized POLD4. Both in vitro and in vivo assays indicated that targeted depletion of the UCHL3-POLD4 axis reduced GSC self-renewal and tumorigenic capacity and resistance to IR treatment by impairing homologous recombination (HR) and nonhomologous end joining (NHEJ). Additionally, we proved that the UCHL3 inhibitor TCID induced POLD4 degradation and can significantly enhance the therapeutic effect of IR in a gsc-derived in situ xenograft model. CONCLUSION: These findings reveal a new signaling axis for GSC PMT regulation and highlight UCHL3-POLD4 as a potential therapeutic target in GBM. TCID, targeted for reducing the deubiquitinase activity of UCHL3, exhibited significant synergy against MES GSCs in combination with radiation.


Assuntos
Células-Tronco Neoplásicas , Tolerância a Radiação , Ubiquitina Tiolesterase , Humanos , Ubiquitina Tiolesterase/metabolismo , Ubiquitina Tiolesterase/genética , Tolerância a Radiação/genética , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/efeitos da radiação , Animais , Camundongos , Linhagem Celular Tumoral , Glioma/patologia , Glioma/genética , Glioma/radioterapia , Glioma/metabolismo , Apoptose/genética , Apoptose/efeitos da radiação , Ubiquitinação , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Camundongos Nus , Fenótipo , Regulação Neoplásica da Expressão Gênica , Prognóstico
9.
Proc Natl Acad Sci U S A ; 119(11): e2121531119, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35259011

RESUMO

SignificancePhotosynthesis metabolites are quickly labeled when 13CO2 is fed to leaves, but the time course of labeling reveals additional contributing processes involved in the metabolic dynamics of photosynthesis. The existence of three such processes is demonstrated, and a metabolic flux model is developed to explore and characterize them. The model is consistent with a slow return of carbon from cytosolic and vacuolar sugars into the Calvin-Benson cycle through the oxidative pentose phosphate pathway. Our results provide insight into how carbon assimilation is integrated into the metabolic network of photosynthetic cells with implications for global carbon fluxes.


Assuntos
Carbono/metabolismo , Redes e Vias Metabólicas , Fotossíntese , Açúcares/metabolismo , Ciclo do Carbono , Dióxido de Carbono/metabolismo , Citosol/metabolismo , Modelos Biológicos , Folhas de Planta/metabolismo , Fenômenos Fisiológicos Vegetais
10.
J Proteome Res ; 23(9): 3746-3753, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39162688

RESUMO

A comprehensive understanding of the exact influence of type 2 diabetes mellitus (T2DM) on the metabolic status of non-small cell lung cancer (NSCLC) is still lacking. This study explores metabolic alterations in tumor tissues among patients with coexisting NSCLC and T2DM in comparison with NSCLC patients. A combined approach of clinical analysis and metabolomics was employed, including 20 NSCLC patients and 20 NSCLC+T2DM patients. Targeted metabolomics analysis was performed on tumor tissues using the liquid chromatography-mass spectrometry (LC-MS) approach. A clear segregation was observed between NSCLC+T2DM and matched NSCLC tissue samples in Orthogonal Partial Least Squares Discrimination Analysis (OPLS-DA). Furthermore, the levels of 7 metabolites are found to be significantly different between diabetes/nondiabetes tumor tissue samples. The related pathways included arginine biosynthesis, glutathione metabolism, arginine and proline metabolism, purine metabolism, biotin metabolism, and histidine metabolism. 3-Phenyllactic acid, carnitine-C5, carnitine-C12, and serotonin showed a positive linear correlation with fasting blood glucose levels in NSCLC patients. Uridine, pipecolic acid, cytosine, and fasting blood glucose levels were found to have a negative correlation. Our results suggest that NSCLC patients with concurrent T2DM exhibit distinct metabolic shifts in tumor tissues compared to those of solely NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Diabetes Mellitus Tipo 2 , Neoplasias Pulmonares , Metabolômica , Humanos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/complicações , Masculino , Metabolômica/métodos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Pessoa de Meia-Idade , Feminino , Idoso , Cromatografia Líquida , Metaboloma , Espectrometria de Massas , Glicemia/metabolismo , Carnitina/metabolismo , Carnitina/análogos & derivados , Arginina/metabolismo
11.
J Cell Mol Med ; 28(12): e18488, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39031896

RESUMO

MCM8 is a helicase, which participates in DNA replication and tumorigenesis and is upregulated in many human cancers, including lung cancer (LC); however, the function of MCM8 in LC tumour progression is unclear. In this study, we found that MCM8 was expressed at high levels in LC cells and tissues. Further, MCM8 upregulation was associated with advanced tumour grade and lymph node metastasis, and indicated poor prognosis. Silencing of MCM8 suppressed cell growth and migration in vitro and in vivo, while ectopic MCM8 expression promoted cell cycle progression, as well as cell migration, proliferation, and apoptosis. Mechanistically, DNAJC10 was identified as a downstream target of MCM8, using gene array and CO-IP assays. DNAJC10 overexpression combatted the inhibitory activity of MCM8 knockdown on LC progression, while silencing DNAJC10 alleviated the oncogenic function of MCM8 overexpression. MCM8 expression was positively correlated with that of DNAJC10 in LC samples from The Cancer Genome Atlas database, and DNAJC10 upregulation was also associated with poor overall survival of patients with LC. This study indicated that MCM8/DNAJC10 axis plays an important role in in LC development, and maybe as a new potential therapeutic target or a diagnostic biomarker for treating patients with LC.


Assuntos
Movimento Celular , Proliferação de Células , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares , Proteínas de Manutenção de Minicromossomo , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Proteínas de Manutenção de Minicromossomo/metabolismo , Proteínas de Manutenção de Minicromossomo/genética , Proliferação de Células/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Masculino , Animais , Feminino , Camundongos , Apoptose/genética , Regulação para Cima/genética , Proteínas de Choque Térmico HSP40/metabolismo , Proteínas de Choque Térmico HSP40/genética , Prognóstico , Camundongos Nus , Pessoa de Meia-Idade , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genética
12.
J Am Chem Soc ; 146(11): 7400-7407, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-38456799

RESUMO

Peptidoglycan (PG), an essential exoskeletal polymer in bacteria, is a well-known antibiotic target. PG polymerization requires the action of bacterial transglycosylases (TGases), which couple the incoming glycosyl acceptor to the donor. Interfering with the TGase activity can interrupt the PG assembly. Existing TGase inhibitors like moenomycin and Lipid II analogues always occupy the TGase active sites; other strategies to interfere with proper PG elongation have not been widely exploited. Inspired by the natural 1,6-anhydro-MurNAc termini that mark the ends of PG strands in bacteria, we hypothesized that the incorporation of an anhydromuramyl-containing glycosyl acceptor by TGase into the growing PG may effectively inhibit PG elongation. To explore this possibility, we synthesized 4-O-(N-acetyl-ß-d-glucosaminyl)-1,6-anhydro-N-acetyl-ß-d-muramyl-l-Ala-γ-d-Glu-l-Lys-d-Ala-d-Ala, 1, within 15 steps, and demonstrated that this anhydromuropeptide and its analogue lacking the peptide, 1-deAA, were both utilized by bacterial TGase as noncanonical anhydro glycosyl acceptors in vitro. The incorporation of an anhydromuramyl moiety into PG strands by TGases afforded efficient termination of glycan chain extension. Moreover, the preliminary in vitro studies of 1-deAA against Staphylococcus aureus showed that 1-deAA served as a reasonable antimicrobial adjunct of vancomycin. These insights imply the potential application of such anhydromuropeptides as novel classes of PG-terminating inhibitors, pointing toward novel strategies in antibacterial agent development.


Assuntos
Antibacterianos , Peptidoglicano , Peptidoglicano/química , Antibacterianos/farmacologia , Bactérias/metabolismo , Glicosiltransferases/metabolismo
13.
J Am Chem Soc ; 146(28): 18967-18978, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38973592

RESUMO

Platensilin, platensimycin, and platencin are potent inhibitors of ß-ketoacyl-acyl carrier protein synthase (FabF) in the bacterial and mammalian fatty acid synthesis system, presenting promising drug leads for both antibacterial and antidiabetic therapies. Herein, a bioinspired skeleton reconstruction approach is reported, which enables the unified synthesis of these three natural FabF inhibitors and their skeletally diverse analogs, all stemming from a common ent-pimarane core. The synthesis features a diastereoselective biocatalytic reduction and an intermolecular Diels-Alder reaction to prepare the common ent-pimarane core. From this intermediate, stereoselective Mn-catalyzed hydrogen atom-transfer hydrogenation and subsequent Cu-catalyzed carbenoid C-H insertion afford platensilin. Furthermore, the intramolecular Diels-Alder reaction succeeded by regioselective ring opening of the newly formed cyclopropane enables the construction of the bicyclo[3.2.1]-octane and bicyclo[2.2.2]-octane ring systems of platensimycin and platencin, respectively. This skeletal reconstruction approach of the ent-pimarane core facilitates the preparation of analogs bearing different polycyclic scaffolds. Among these analogs, the previously unexplored cyclopropyl analog 47 exhibits improved antibacterial activity (MIC80 = 0.0625 µg/mL) against S. aureus compared to platensimycin.


Assuntos
Adamantano , Aminobenzoatos , Aminofenóis , Anilidas , Compostos Policíclicos , Aminofenóis/química , Aminofenóis/farmacologia , Aminofenóis/síntese química , Compostos Policíclicos/química , Compostos Policíclicos/farmacologia , Compostos Policíclicos/síntese química , Adamantano/química , Adamantano/farmacologia , Adamantano/síntese química , Adamantano/análogos & derivados , Anilidas/farmacologia , Anilidas/química , Anilidas/síntese química , Aminobenzoatos/farmacologia , Aminobenzoatos/química , Aminobenzoatos/síntese química , Antibacterianos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Staphylococcus aureus/efeitos dos fármacos , Estrutura Molecular , Reação de Cicloadição , Testes de Sensibilidade Microbiana , Estereoisomerismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química
14.
Curr Issues Mol Biol ; 46(9): 9916-9927, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39329943

RESUMO

Dermatan sulfate and chondroitin sulfate are dietary supplements that can be utilized as prophylactics against thrombus formation. Low-molecular-weight dermatan sulfate (LMWDS) is particularly advantageous due to its high absorbability. The enzymatic synthesis of low-molecular-weight dermatan sulfates (LMWDSs) using chondroitin B lyase is a sustainable and environmentally friendly approach to manufacturing. However, the industrial application of chondroitin B lyases is severely hampered by their low catalytic activity. To improve the activity, a semi-rational design strategy of engineering the substrate-binding domain of chondroitin B lyase was performed based on the structure. The binding domain was subjected to screening of critical residues for modification using multiple sequence alignments and molecular docking. A total of thirteen single-point mutants were constructed and analyzed to assess their catalytic characteristics. Out of these, S90T, N103C, H134Y, and R159K exhibited noteworthy enhancements in activity. This study also examined combinatorial mutagenesis and found that the mutant H134Y/R159K exhibited a substantially enhanced catalytic activity of 1266.74 U/mg, which was 3.21-fold that of the wild-type one. Molecular docking revealed that the enhanced activity of the mutant could be attributed to the formation of new hydrogen bonds and hydrophobic interactions with the substrate as well as neighbor residues. The highly active mutant would benefit the utilization of chondroitin B lyase in pharmaceuticals and functional foods.

15.
Cancer Sci ; 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223585

RESUMO

This study utilized data from 140,294 prostate cancer cases from the Surveillance, Epidemiology, and End Results (SEER) database. Here, 10 different machine learning algorithms were applied to develop treatment options for predicting patients with prostate cancer, differentiating between surgical and non-surgical treatments. The performances of the algorithms were measured using the area under the receiver operating characteristic curve (AUC), accuracy, sensitivity, specificity, positive predictive value, negative predictive value. The Shapley Additive Explanations (SHAP) method was employed to investigate the key factors influencing the prediction process. Survival analysis methods were used to compare the survival rates of different treatment options. The CatBoost model yielded the best results (AUC = 0.939, sensitivity = 0.877, accuracy = 0.877). SHAP interpreters revealed that the T stage, cancer stage, age, cores positive percentage, prostate-specific antigen, and Gleason score were the most critical factors in predicting treatment options. The study found that surgery significantly improved survival rates, with patients undergoing surgery experiencing a 20.36% increase in 10-year survival rates compared with those receiving non-surgical treatments. Among surgical options, radical prostatectomy had the highest 10-year survival rate at 89.2%. This study successfully developed a predictive model to guide treatment decisions for prostate cancer. Moreover, the model enhanced the transparency of the decision-making process, providing clinicians with a reference for formulating personalized treatment plans.

16.
Br J Cancer ; 130(4): 585-596, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172534

RESUMO

BACKGROUND: The enriched proteins within in vitro fertilisation (IVF)-generated human embryonic microenvironment could reverse progestin resistance in endometrial cancer (EC). METHODS: The expression of thymic stromal lymphopoietin (TSLP) in EC was evaluated by immunoblot and IHC analysis. Transcriptome sequencing screened out the downstream pathway regulated by TSLP. The role of TSLP, androgen receptor (AR) and KANK1 in regulating the sensitivity of EC to progestin was verified through a series of in vitro and in vivo experiments. RESULTS: TSLP facilitates the formation of a BMP4/BMP7 heterodimer, resulting in activation of Smad5, augmenting AR signalling. AR in turn sensitises EC cells to progestin via KANK1. Downregulation of TSLP, loss of AR and KANK1 in EC patients are associated with tumour malignant progress. Moreover, exogenous TSLP could rescue the anti-tumour effect of progestin on mouse in vivo xenograft tumour. CONCLUSIONS: Our findings suggest that TSLP enhances the sensitivity of EC to progestin through the BMP4/Smad5/AR/KANK1 axis, and provide a link between embryo development and cancer progress, paving the way for the establishment of novel strategy overcoming progestin resistance using embryo original factors.


Assuntos
Neoplasias do Endométrio , Linfopoietina do Estroma do Timo , Animais , Feminino , Humanos , Camundongos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Citocinas/metabolismo , Proteínas do Citoesqueleto/metabolismo , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/genética , Progestinas/farmacologia , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Transdução de Sinais , Microambiente Tumoral
17.
Clin Immunol ; 261: 109929, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38331303

RESUMO

Previous studies have shown that epigenetic factors are involved in the occurrence and development of rheumatoid arthritis (RA). However, the role of N6-methyladenosine (m6A) methylation in RA has not been determined. The aim of this study was to investigate the role and regulatory mechanisms of hypoxia-induced expression of the m6A demethylase alkB homolog 5 (ALKBH5) in RA fibroblast-like synoviocytes (FLSs). Synovial tissues were collected from RA and osteoarthritis (OA) patients, and RA FLSs were obtained. ALKBH5 expression in RA FLSs and collagen-induced arthritis (CIA) model rats was determined using quantitative reverse transcription-PCR (qRT-PCR), western blotting and immunohistochemistry (IHC). Using ALKBH5 overexpression and knockdown, we determined the role of ALKBH5 in RA FLS aggression and inflammation. The role of ALKBH5 in RA FLS regulation was explored using m6A-methylated RNA sequencing and methylated RNA immunoprecipitation coupled with quantitative real-time PCR. The expression of ALKBH5 was increased in RA synovial tissues, CIA model rats and RA FLSs, and a hypoxic environment increased the expression of ALKBH5 in FLSs. Increased expression of ALKBH5 promoted the proliferation and migration of RA-FLSs and inflammation. Conversely, decreased ALKBH5 expression inhibited the migration of RA-FLSs and inflammation. Mechanistically, hypoxia-induced ALKBH5 expression promoted FLS aggression and inflammation by regulating CH25H mRNA stability. Our study elucidated the functional roles of ALKBH5 and mRNA m6A methylation in RA and revealed that the HIF1α/2α-ALKBH5-CH25H pathway may be key for FLS aggression and inflammation. This study provides a novel approach for the treatment of RA by targeting the HIF1α/2α-ALKBH5-CH25H pathway.


Assuntos
Adenina/análogos & derivados , Agressão , Artrite Reumatoide , Humanos , Ratos , Animais , Artrite Reumatoide/genética , Artrite Reumatoide/metabolismo , Inflamação/metabolismo , Hipóxia , Fibroblastos/metabolismo , Proliferação de Células , Células Cultivadas , Homólogo AlkB 5 da RNA Desmetilase/genética , Homólogo AlkB 5 da RNA Desmetilase/metabolismo
18.
Br J Haematol ; 204(6): 2418-2428, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38513635

RESUMO

This study aimed to identify key proteomic analytes correlated with response to splenectomy in primary immune thrombocytopenia (ITP). Thirty-four patients were retrospectively collected in the training cohort and 26 were prospectively enrolled as validation cohort. Bone marrow biopsy samples of all participants were collected prior to the splenectomy. A total of 12 modules of proteins were identified by weighted gene co-expression network analysis (WGCNA) method in the developed cohort. The tan module positively correlated with megakaryocyte counts before splenectomy (r = 0.38, p = 0.027), and time to peak platelet level after splenectomy (r = 0.47, p = 0.005). The blue module significantly correlated with response to splenectomy (r = 0.37, p = 0.0031). KEGG pathways analysis found that the PI3K-Akt signalling pathway was predominantly enriched in the tan module, while ribosomal and spliceosome pathways were enriched in the blue module. Machine learning algorithm identified the optimal combination of biomarkers from the blue module in the training cohort, and importantly, cofilin-1 (CFL1) was independently confirmed in the validation cohort. The C-index of CFL1 was >0.7 in both cohorts. Our results highlight the use of bone marrow proteomics analysis for deriving key analytes that predict the response to splenectomy, warranting further exploration of plasma proteomics in this patient population.


Assuntos
Aprendizado de Máquina , Proteômica , Púrpura Trombocitopênica Idiopática , Esplenectomia , Humanos , Masculino , Feminino , Proteômica/métodos , Púrpura Trombocitopênica Idiopática/cirurgia , Púrpura Trombocitopênica Idiopática/sangue , Púrpura Trombocitopênica Idiopática/genética , Adulto , Pessoa de Meia-Idade , Biomarcadores/sangue , Idoso , Estudos Retrospectivos
19.
Br J Haematol ; 204(4): 1207-1218, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37967471

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic has a significant impact on the immune system. This is the first and largest study on pre-existing immune thrombocytopenia (ITP) patients infected with COVID-19 in China. We prospectively collected ITP patients infected with COVID-19 enrolled in the National Longitudinal Cohort of Hematological Diseases (NICHE, NCT04645199) and followed up for at least 1 month after infection. One thousand and one hundred forty-eight pre-existing ITP patients were included. Two hundred and twelve (18.5%) patients showed a decrease in the platelet (PLT) count after infection. Forty-seven (4.1%) patients were diagnosed with pneumonia. Risk factors for a decrease in the PLT count included baseline PLT count <50 × 109/L (OR, 1.76; 95% CI, 1.25-2.46; p = 0.001), maintenance therapy including thrombopoietin receptor agonists (TPO-RAs) (OR, 2.27; 95% CI, 1.60-3.21; p < 0.001) and previous splenectomy (OR, 1.98; 95% CI, 1.09-3.61; p = 0.03). Risk factors for pneumonia included age ≥40 years (OR, 2.45; 95% CI, 1.12-5.33; p = 0.02), ≥2 comorbidities (OR, 3.47; 95% CI, 1.63-7.64; p = 0.001), maintenance therapy including TPO-RAs (OR, 2.14; 95% CI, 1.17-3.91; p = 0.01) and immunosuppressants (OR, 3.05; 95% CI, 1.17-7.91; p = 0.02). In this cohort study, we described the characteristics of pre-existing ITP patients infected with COVID-19 and identified several factors associated with poor outcomes.


Assuntos
COVID-19 , Púrpura Trombocitopênica Idiopática , Trombocitopenia , Humanos , Adulto , Púrpura Trombocitopênica Idiopática/epidemiologia , Púrpura Trombocitopênica Idiopática/terapia , Estudos de Coortes , Estudos Prospectivos , Trombocitopenia/epidemiologia , Trombocitopenia/etiologia , Trombopoetina , Proteínas Recombinantes de Fusão , Receptores Fc , Hidrazinas
20.
Anal Chem ; 96(24): 9961-9968, 2024 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-38838250

RESUMO

In this study, a novel europium dual-ligand metal-organic gel (Eu-D-MOGs) with high-efficient anodic annihilation electrochemiluminescence (ECL) was synthesized as an ECL emitter to construct a biosensor for ultrasensitive detection of microRNA-221 (miR-221). Impressively, compared to the ECL signal of europium single-ligand metal-organic gels (Eu-S-MOGs), the ECL signal of Eu-D-MOGs was significantly improved since the two organic ligands could jointly replace the H2O and coordinate with Eu3+, which could remarkably reduce the nonradiative vibrational energy transfer caused by the coordination between H2O and Eu3+ with a high coordination demand. In addition, Eu-D-MOGs could be electrochemically oxidized to Eu-D-MOGs•+ at 1.45 V and reduced to Eu-D-MOGs•- at 0.65 V to achieve effective annihilation of ECL, which overcame the side reaction brought by the remaining emitters at negative potential. This benefited from the annihilation ECL performance of the central ion Eu3+ caused by its redox in the electrochemical process. Furthermore, the annihilation ECL signal of Eu3+ could be improved by sensitizing Eu3+ via the antenna effect. In addition, combined with the improved rolling circle amplification-assisted strand displacement amplification strategy (RCA-SDA), a sensitive biosensor was constructed for the sensitive detection of miR-221 with a low detection limit of 5.12 aM and could be successfully applied for the detection of miR-221 in the lysate of cancer cells. This strategy offered a unique approach to synthesizing metal-organic gels as ECL emitters without a coreactant for the construction of ECL biosensing platforms in biomarker detection and disease diagnosis.


Assuntos
Técnicas Eletroquímicas , Eletrodos , Európio , Géis , Medições Luminescentes , MicroRNAs , Európio/química , MicroRNAs/análise , Técnicas Eletroquímicas/métodos , Ligantes , Géis/química , Técnicas Biossensoriais/métodos , Limite de Detecção , Humanos
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