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1.
Cell ; 187(15): 3992-4009.e25, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38866019

RESUMO

Metazoan genomes are copied bidirectionally from thousands of replication origins. Replication initiation entails the assembly and activation of two CMG helicases (Cdc45⋅Mcm2-7⋅GINS) at each origin. This requires several replication firing factors (including TopBP1, RecQL4, and DONSON) whose exact roles are still under debate. How two helicases are correctly assembled and activated at each origin is a long-standing question. By visualizing the recruitment of GINS, Cdc45, TopBP1, RecQL4, and DONSON in real time, we uncovered that replication initiation is surprisingly dynamic. First, TopBP1 transiently binds to the origin and dissociates before the start of DNA synthesis. Second, two Cdc45 are recruited together, even though Cdc45 alone cannot dimerize. Next, two copies of DONSON and two GINS simultaneously arrive at the origin, completing the assembly of two CMG helicases. Finally, RecQL4 is recruited to the CMG⋅DONSON⋅DONSON⋅CMG complex and promotes DONSON dissociation and CMG activation via its ATPase activity.


Assuntos
Proteínas de Ciclo Celular , Replicação do DNA , Imagem Individual de Molécula , Humanos , Proteínas de Ciclo Celular/metabolismo , Origem de Replicação , Animais , DNA Helicases/metabolismo , RecQ Helicases/metabolismo , Proteínas de Ligação a DNA/metabolismo
2.
Cell ; 156(6): 1312-1323, 2014 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-24612990

RESUMO

Models of transcription are often built around a picture of RNA polymerase and transcription factors (TFs) acting on a single copy of a promoter. However, most TFs are shared between multiple genes with varying binding affinities. Beyond that, genes often exist at high copy number-in multiple identical copies on the chromosome or on plasmids or viral vectors with copy numbers in the hundreds. Using a thermodynamic model, we characterize the interplay between TF copy number and the demand for that TF. We demonstrate the parameter-free predictive power of this model as a function of the copy number of the TF and the number and affinities of the available specific binding sites; such predictive control is important for the understanding of transcription and the desire to quantitatively design the output of genetic circuits. Finally, we use these experiments to dynamically measure plasmid copy number through the cell cycle.


Assuntos
Escherichia coli/metabolismo , Expressão Gênica , Modelos Genéticos , Fatores de Transcrição/metabolismo , Escherichia coli/genética , Dosagem de Genes , Regulação Bacteriana da Expressão Gênica , Plasmídeos , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Termodinâmica , Transcrição Gênica
3.
Nature ; 565(7739): 372-376, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30626964

RESUMO

For more than 50 years, the methylation of mammalian actin at histidine 73 has been known to occur1. Despite the pervasiveness of His73 methylation, which we find is conserved in several model animals and plants, its function remains unclear and the enzyme that generates this modification is unknown. Here we identify SET domain protein 3 (SETD3) as the physiological actin His73 methyltransferase. Structural studies reveal that an extensive network of interactions clamps the actin peptide onto the surface of SETD3 to orient His73 correctly within the catalytic pocket and to facilitate methyl transfer. His73 methylation reduces the nucleotide-exchange rate on actin monomers and modestly accelerates the assembly of actin filaments. Mice that lack SETD3 show complete loss of actin His73 methylation in several tissues, and quantitative proteomics analysis shows that actin His73 methylation is the only detectable physiological substrate of SETD3. SETD3-deficient female mice have severely decreased litter sizes owing to primary maternal dystocia that is refractory to ecbolic induction agents. Furthermore, depletion of SETD3 impairs signal-induced contraction in primary human uterine smooth muscle cells. Together, our results identify a mammalian histidine methyltransferase and uncover a pivotal role for SETD3 and actin His73 methylation in the regulation of smooth muscle contractility. Our data also support the broader hypothesis that protein histidine methylation acts as a common regulatory mechanism.


Assuntos
Actinas/química , Actinas/metabolismo , Distocia/enzimologia , Distocia/prevenção & controle , Histidina/química , Histidina/metabolismo , Metiltransferases/metabolismo , Animais , Linhagem Celular , Feminino , Histona Metiltransferases , Histonas , Tamanho da Ninhada de Vivíparos/genética , Masculino , Metilação , Metiltransferases/deficiência , Metiltransferases/genética , Camundongos , Modelos Moleculares , Músculo Liso/citologia , Músculo Liso/fisiologia , Gravidez , Proteômica , Contração Uterina , Útero/citologia , Útero/fisiologia
4.
Mol Ther ; 32(8): 2778-2797, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-38822524

RESUMO

Dysregulated T cell activation underpins the immunopathology of rheumatoid arthritis (RA), yet the machineries that orchestrate T cell effector program remain incompletely understood. Herein, we leveraged bulk and single-cell RNA sequencing data from RA patients and validated protein disulfide isomerase family A member 3 (PDIA3) as a potential therapeutic target. PDIA3 is remarkably upregulated in pathogenic CD4 T cells derived from RA patients and positively correlates with C-reactive protein level and disease activity score 28. Pharmacological inhibition or genetic ablation of PDIA3 alleviates RA-associated articular pathology and autoimmune responses. Mechanistically, T cell receptor signaling triggers intracellular calcium flux to activate NFAT1, a process that is further potentiated by Wnt5a under RA settings. Activated NFAT1 then directly binds to the Pdia3 promoter to enhance the expression of PDIA3, which complexes with STAT1 or PKM2 to facilitate their nuclear import for transcribing T helper 1 (Th1) and Th17 lineage-related genes, respectively. This non-canonical regulatory mechanism likely occurs under pathological conditions, as PDIA3 could only be highly induced following aberrant external stimuli. Together, our data support that targeting PDIA3 is a vital strategy to mitigate autoimmune diseases, such as RA, in clinical settings.


Assuntos
Artrite Reumatoide , Isomerases de Dissulfetos de Proteínas , Fator de Transcrição STAT1 , Isomerases de Dissulfetos de Proteínas/metabolismo , Isomerases de Dissulfetos de Proteínas/genética , Humanos , Artrite Reumatoide/metabolismo , Camundongos , Animais , Fator de Transcrição STAT1/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Transporte Ativo do Núcleo Celular , Proteínas de Transporte/metabolismo , Transdução de Sinais , Proteínas de Ligação a Hormônio da Tireoide , Fatores de Transcrição NFATC/metabolismo , Ativação Linfocitária , Hormônios Tireóideos/metabolismo , Regulação da Expressão Gênica , Células Th17/metabolismo , Células Th17/imunologia , Células Th1/imunologia , Células Th1/metabolismo , Modelos Animais de Doenças , Piruvato Quinase
5.
Proc Natl Acad Sci U S A ; 119(44): e2207975119, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36279435

RESUMO

Stress granules (SGs) are cytoplasmic biomolecular condensates containing proteins and RNAs in response to stress. Ras-GTPase-activating protein binding protein 1 (G3BP1) is a core SG protein. Caprin-1 and ubiquitin specific peptidase 10 (USP10) interact with G3BP1, facilitating and suppressing SG formation, respectively. The crystal structures of the nuclear transport factor 2-like (NTF2L) domain of G3BP1 in complex with the G3BP1-interacting motif (GIM) of Caprin-1 and USP10 show that both GIMs bind to the same hydrophobic pocket of G3BP1. Moreover, both GIMs suppressed the liquid-liquid phase separation (LLPS) of G3BP1, suggesting that Caprin-1 likely facilitates SG formation via other mechanisms. Thus, we dissected various domains of Caprin-1 and investigated their role in LLPS in vitro and SG formation in cells. The C-terminal domain of Caprin-1 underwent spontaneous LLPS, whereas the N-terminal domain and GIM of Caprin-1 suppressed LLPS of G3BP1. The opposing effect of the N- and C-terminal domains of Caprin-1 on SG formation were demonstrated in cells with or without the endogenous Caprin-1. We propose that the N- and C-terminal domains of Caprin-1 regulate SG formation in a "yin and yang" fashion, mediating the dynamic and reversible assembly of SGs.


Assuntos
DNA Helicases , RNA Helicases , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , RNA Helicases/metabolismo , DNA Helicases/metabolismo , Grânulos Citoplasmáticos/metabolismo , Grânulos de Estresse , Proteínas Ativadoras de GTPase/metabolismo , Proteases Específicas de Ubiquitina/metabolismo
6.
Hum Mol Genet ; 31(21): 3652-3671, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-35388883

RESUMO

Wilson's disease (WD) is a copper metabolic disorder caused by a defective ATP7B function. Conventional therapies cause severe side effects and significant variation in efficacy, according to cohort studies. Thus, exploring new therapeutic approaches to prevent progression to liver failure is urgent. To study the physiology and pathology of WD, immortalized cell lines and rodent WD models have been used conventionally; however, a large gap remains among different species as well as in genetic backgrounds among individuals. We generated induced pluripotent stem cells (iPSCs) from four WD patients carrying compound heterozygous mutations in the ATP7B gene. ATP7B loss- and gain-of-functions were further manifested with ATP7B-deficient iPSCs and heterozygously corrected R778L WD patient-derived iPSCs using CRISPR-Cas9-based gene editing. Although the expression of ATP7B protein varied among WD-specific hepatocytes differentiated from these iPSCs, the expression and secretion of ceruloplasmin (Cp), a downstream copper carrier in plasma, were consistently decreased in WD patient-derived and ATP7B-deficient hepatocytes. A transcriptome analysis detected abnormalities in the retinoid signaling pathway and lipid metabolism in WD-specific hepatocytes. Drug screening using WD patient-derived hepatocytes identified retinoids as promising candidates for rescuing Cp secretion. All-trans retinoic acid also alleviates reactive oxygen species production induced by lipid accumulation in WD-specific hepatocytes treated with oleic acid. These patient-derived iPSC-based hepatic models function as effective platforms for the development of potential therapeutics for hepatic steatosis in WD and other fatty liver diseases.


Assuntos
Degeneração Hepatolenticular , Humanos , Degeneração Hepatolenticular/tratamento farmacológico , Degeneração Hepatolenticular/genética , Ceruloplasmina/genética , Ceruloplasmina/metabolismo , Cobre/metabolismo , Retinoides/metabolismo , Retinoides/uso terapêutico , ATPases Transportadoras de Cobre/genética , Hepatócitos/metabolismo , Estresse Oxidativo , Mutação
7.
J Neuroinflammation ; 21(1): 250, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39367382

RESUMO

BACKGROUND: IL-2 regulates T cell differentiation: low-dose IL-2 induces immunoregulatory Treg differentiation, while high-dose IL-2 acts as a potent activator of cytotoxic T cells and NK cells. Therefore, high-dose IL-2 has been studied for use in cancer immunotherapy. We aimed to utilize low-dose IL-2 to treat inflammatory diseases such as obesity and insulin resistance, which involve low-grade chronic inflammation. MAIN BODY: Systemic administration of low-dose IL-2 increased Treg cells and decreased inflammation in gonadal white adipose tissue (gWAT), leading to improved insulin sensitivity in high-fat diet-fed obese mice. Additionally, central administration of IL-2 significantly enhanced insulin sensitivity through the activation of the sympathetic nervous system. The sympathetic signaling induced by central IL-2 administration not only decreased interferon γ (IFNγ) + Th1 cells and the expression of pro-inflammatory cytokines, including Il-1ß, Il-6, and Il-8, but also increased CD4 + CD25 + FoxP3 + Treg cells and Tgfß expression in the gWAT of obese mice. These phenomena were accompanied by hypothalamic microgliosis and activation of pro-opiomelanocortin neurons. Furthermore, sympathetic denervation in gWAT reversed the enhanced insulin sensitivity and immune cell polarization induced by central IL-2 administration. CONCLUSION: Overall, we demonstrated that IL-2 improves insulin sensitivity through two mechanisms: direct action on CD4 + T cells and via the neuro-immune axis triggered by hypothalamic microgliosis.


Assuntos
Hipotálamo , Resistência à Insulina , Interleucina-2 , Camundongos Endogâmicos C57BL , Obesidade , Sistema Nervoso Simpático , Animais , Camundongos , Resistência à Insulina/fisiologia , Interleucina-2/metabolismo , Obesidade/metabolismo , Hipotálamo/metabolismo , Hipotálamo/efeitos dos fármacos , Sistema Nervoso Simpático/efeitos dos fármacos , Masculino , Dieta Hiperlipídica/efeitos adversos , Camundongos Obesos , Linfócitos T Reguladores/efeitos dos fármacos
8.
Small ; : e2405586, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39235375

RESUMO

Direct laser writing has gained remarkable popularity by offering architectural control of 3D objects at submicron scales. However, it faces limitations when the fabrication of microstructures comprising multiple materials is desired. The generation processes of multi-material microstructures are often very complex, requiring meticulous alignment, as well as a series of step-and-repeat writing and development of the materials. Here, a novel material system based on multilayers of chemically tailored polymers containing anthraquinone crosslinker units is demonstrated. Upon two-photon excitation, the crosslinkers only require nearby aliphatic C,H units as reaction partners to form a crosslinked network. The desired structure can be written into a solid multi-layered material system, wherein the properties of each material can be designed at the molecular level. In this way, C,H insertion crosslinking (CHic) of the polymers within each layer, along with simultaneous reaction at their interfaces, is performed, leading to the one-step fabrication of multi-material microstructures. A multi-material 3D scaffold with a sixfold symmetry is produced to precisely control the adhesion of cells both concerning surface chemistry and topology. The demonstrated material system shows great promise for the fabrication of 3D microstructures with high precision, intricate geometries and customized functionalities.

9.
Plant Biotechnol J ; 22(5): 1113-1131, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38038155

RESUMO

Self-incompatibility (SI) is a widespread prezygotic mechanism for flowering plants to avoid inbreeding depression and promote genetic diversity. Citrus has an S-RNase-based SI system, which was frequently lost during evolution. We previously identified a single nucleotide mutation in Sm-RNase, which is responsible for the loss of SI in mandarin and its hybrids. However, little is known about other mechanisms responsible for conversion of SI to self-compatibility (SC) and we identify a completely different mechanism widely utilized by citrus. Here, we found a 786-bp miniature inverted-repeat transposable element (MITE) insertion in the promoter region of the FhiS2-RNase in Fortunella hindsii Swingle (a model plant for citrus gene function), which does not contain the Sm-RNase allele but are still SC. We demonstrate that this MITE plays a pivotal role in the loss of SI in citrus, providing evidence that this MITE insertion prevents expression of the S-RNase; moreover, transgenic experiments show that deletion of this 786-bp MITE insertion recovers the expression of FhiS2-RNase and restores SI. This study identifies the first evidence for a role for MITEs at the S-locus affecting the SI phenotype. A family-wide survey of the S-locus revealed that MITE insertions occur frequently adjacent to S-RNase alleles in different citrus genera, but only certain MITEs appear to be responsible for the loss of SI. Our study provides evidence that insertion of MITEs into a promoter region can alter a breeding strategy and suggests that this phenomenon may be broadly responsible for SC in species with the S-RNase system.


Assuntos
Citrus , Elementos de DNA Transponíveis , Elementos de DNA Transponíveis/genética , Citrus/genética , Melhoramento Vegetal , Mutação , Ribonucleases/metabolismo
10.
J Transl Med ; 22(1): 58, 2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38221609

RESUMO

BACKGROUND: Chimeric antigen receptor CAR-T cell therapies have ushered in a new era of treatment for specific blood cancers, offering unparalleled efficacy in cases of treatment resistance or relapse. However, the emergence of cytokine release syndrome (CRS) as a side effect poses a challenge to the widespread application of CAR-T cell therapies. Melatonin, a natural hormone produced by the pineal gland known for its antioxidant and anti-inflammatory properties, has been explored for its potential immunomodulatory effects. Despite this, its specific role in mitigating CAR-T cell-induced CRS remains poorly understood. METHODS: In this study, our aim was to investigate the potential of melatonin as an immunomodulatory agent in the context of CD19-targeting CAR-T cell therapy and its impact on associated side effects. Using a mouse model, we evaluated the effects of melatonin on CAR-T cell-induced CRS and overall survival. Additionally, we assessed whether melatonin administration had any detrimental effects on the antitumor efficacy and persistence of CD19 CAR-T cells. RESULTS: Our findings demonstrate that melatonin effectively mitigated the severity of CAR-T cell-induced CRS in the mouse model, leading to improved overall survival outcomes. Remarkably, melatonin administration did not compromise the antitumor effectiveness or persistence of CD19 CAR-T cells, indicating its compatibility with therapeutic goals. These results suggest melatonin's potential as an immunomodulatory compound to alleviate CRS without compromising the therapeutic benefits of CAR-T cell therapy. CONCLUSION: The study's outcomes shed light on melatonin's promise as a valuable addition to the existing treatment protocols for CAR-T cell therapies. By attenuating CAR-T cell-induced CRS while preserving the therapeutic impact of CAR-T cells, melatonin offers a potential strategy for optimizing and refining the safety and efficacy profile of CAR-T cell therapy. This research contributes to the evolving understanding of how to harness immunomodulatory agents to enhance the clinical application of innovative cancer treatments.


Assuntos
Síndrome da Liberação de Citocina , Imunoterapia Adotiva , Melatonina , Antígenos CD19 , Terapia Baseada em Transplante de Células e Tecidos , Síndrome da Liberação de Citocina/terapia , Fatores Imunológicos/farmacologia , Imunoterapia Adotiva/efeitos adversos , Melatonina/farmacologia , Recidiva Local de Neoplasia , Receptores de Antígenos de Linfócitos T , Receptores de Antígenos Quiméricos , Animais , Camundongos
11.
J Exp Bot ; 75(13): 3891-3902, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38486360

RESUMO

Self-incompatibility (SI) is a crucial mechanism that prevents self-fertilization and inbreeding in flowering plants. Citrus exhibits SI regulated by a polymorphic S-locus containing an S-RNase gene and multiple S-locus F-box (SLF) genes. It has been documented that S-RNase functions as the pistil S determinant, but there is no direct evidence that the SLF genes closely linked with S-RNase function as pollen S determinants in Citrus. This study assembled the genomes of two pummelo (Citrus grandis) plants, obtained three novel complete and well-annotated S-haplotypes, and isolated 36 SLF or SLF-like alleles on the S-loci. Phylogenetic analysis of 138 SLFs revealed that the SLF genes were classified into 12 types, including six types with divergent or missing alleles. Furthermore, transformation experiments verified that the conserved S6-SLF7a protein can lead to the transition of SI to self-compatibility by recognizing non-self S8-RNase in 'Mini-Citrus' plants (S7S8 and S8S29, Fortunella hindsii), a model plant for citrus gene function studies. In vitro assays demonstrated interactions between SLFs of different S haplotypes and the Skp1-Cullin1-F-box subunit CgSSK1 protein. This study provides direct evidence that SLF controls the pollen function in Citrus, demonstrating its role in the 'non-self recognition' SI system.


Assuntos
Citrus , Proteínas F-Box , Filogenia , Proteínas de Plantas , Pólen , Ribonucleases , Autoincompatibilidade em Angiospermas , Citrus/genética , Citrus/fisiologia , Citrus/metabolismo , Autoincompatibilidade em Angiospermas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pólen/genética , Pólen/fisiologia , Proteínas F-Box/genética , Proteínas F-Box/metabolismo , Ribonucleases/metabolismo , Ribonucleases/genética , Sequência de Aminoácidos
12.
Haematologica ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39234866

RESUMO

Patients with relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL) have a poor prognosis. Loncastuximab tesirine (Lonca), an antibody conjugate targeting CD19, has demonstrated significant clinical benefit in R/R DLBCL in a global phase 2 LOTIS-2 study. In the China bridging pivotal phase 2 OL-ADCT-402-001 study, eligible patients aged ≥18 years with R/R DLBCL who had failed ≥ 2 lines of systemic therapies were enrolled and treated with Lonca every 3 week with 150 µg/kg for 2 cycles; then 75 µg/kg for subsequent cycles (up to 1 year). The primary endpoint was overall response rate (ORR) assessed by independent review committee. Primary analyses for efficacy and safety were performed on the patients who received at least one treatment and had at least 6 months of follow-up following an initial documented response. As of data-cutoff, 64 patients received Lonca (median: 4.0 cycles [range: 1 to 17]). The median number of prior lines of therapies was 3.0 (range: 2 to 12). The ORR was 51.6% (95% CI: 38.7% to 64.2%), and the complete response rate was 23.4%. Hematological events accounted for the majority of the most common (≥15%) Grade ≥3 treatment-emergent adverse events (TEAEs), in which increased gamma glutamyltransferase (25.0%), and hypokalaemia (18.8%) also were reported. Serious TEAEs were reported in 35 of 64 patients with 4 fatal TEAEs. In conclusion, Lonca monotherapy demonstrated clinically meaningful efficacy and was well-tolerated in heavily pretreated Chinese patients with R/R DLBCL, which was consistent with the results of the LOTIS-2 study in Caucasian patients.

13.
Cell Commun Signal ; 22(1): 220, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589923

RESUMO

Endosomal single-stranded RNA-sensing Toll-like receptor-7/8 (TLR7/8) plays a pivotal role in inflammation and immune responses and autoimmune diseases. However, the mechanisms underlying the initiation of the TLR7/8-mediated autoimmune signaling remain to be fully elucidated. Here, we demonstrate that miR-574-5p is aberrantly upregulated in tissues of lupus prone mice and in the plasma of lupus patients, with its expression levels correlating with the disease activity. miR-574-5p binds to and activates human hTLR8 or its murine ortholog mTlr7 to elicit a series of MyD88-dependent immune and inflammatory responses. These responses include the overproduction of cytokines and interferons, the activation of STAT1 signaling and B lymphocytes, and the production of autoantigens. In a transgenic mouse model, the induction of miR-574-5p overexpression is associated with increased secretion of antinuclear and anti-dsDNA antibodies, increased IgG and C3 deposit in the kidney, elevated expression of inflammatory genes in the spleen. In lupus-prone mice, lentivirus-mediated silencing of miR-574-5p significantly ameliorates major symptoms associated with lupus and lupus nephritis. Collectively, these results suggest that the miR-574-5p-hTLR8/mTlr7 signaling is an important axis of immune and inflammatory responses, contributing significantly to the development of lupus and lupus nephritis.


Assuntos
Nefrite Lúpica , MicroRNAs , Humanos , Camundongos , Animais , Nefrite Lúpica/genética , Receptor 7 Toll-Like/genética , Receptor 7 Toll-Like/metabolismo , Receptor 8 Toll-Like/genética , Receptor 8 Toll-Like/metabolismo , Rim/metabolismo , Camundongos Transgênicos , MicroRNAs/genética
14.
Langmuir ; 40(16): 8427-8439, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38607689

RESUMO

This work aims to enhance the adsorption performance of Laponite @diatomite for organic pollutants by modifying it with cetyltrimethylammonium bromide (CTAB). The microstructure and morphology of the CTAB-modified Laponite @diatomite material were characterized using SEM, XRD, FTIR, BET, and TG. Furthermore, the influences of key parameters, containing pH, adsorbent dosage, reaction time, and reaction temperature, on the adsorption process were investigated. The kinetics, thermodynamics, and isotherm models of the adsorption process were analyzed. Finally, potential adsorption mechanisms were given based on the characterization. The research findings indicate that CTAB-La@D exhibits good adsorption performance toward Congo red (CR) over a broad pH range. The maximum adsorption capacity of CR was 451.1 mg/g under the optimum conditions (dosage = 10 mg, contact time = 240 min, initial CR concentration = 100 mg/L, temperature = 25 °C, and pH = 7). The adsorption process conformed to the pseudo-second-order kinetic model, and the adsorption isotherms indicated that the adsorption process of CR was more in line with the Langmuir model, and it was physical adsorption. Thermodynamic analysis illustrates that the adsorption process is exothermic and spontaneous. Additionally, the mechanisms of electrostatic adsorption and hydrophobic effect adsorption of CR were investigated through XPS and FTIR analysis. This work provides an effective pathway for designing high-performance adsorbents for the removal of organic dye, and the synthesized materials hold great capability for practical utilization in the treatment of wastewater.

15.
J Org Chem ; 89(20): 14658-14664, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-38836310

RESUMO

Photoactivatable (PA) rhodamine dyes are widely used in single-molecule tracking (SMT) and a variety of other fluorescence-based imaging modalities. One of the most commonly employed scaffolds uses a diazoketone to lock the rhodamine in the nonfluorescent closed form, which can be activated with 405 nm light. However, poor properties of previously reported dyes require significant washing, which can be resource- and cost-intensive, especially when performing microscopy in a large scale and high-throughput fashion. Here, we report improved diazoketorhodamines that perform exceptionally well in single-molecule tracking microscopy. We also report on the optimization of an improved synthetic method for further iteration and tailoring of diazoketorhodamines to the requirements of a specific user.

16.
Inorg Chem ; 63(28): 13014-13021, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38943593

RESUMO

Zwitterionic thiolate ligands have the potential to introduce novel assembly modes and functions for noble metal clusters. However, their utilization in the synthesis of silver clusters remains understudied, particularly for the clusters containing reductive Ag(0) species. In this article, we report the first synthesis of a mixed-valence silver(0/I) cluster protected by zwitterionic Tab as thiolate ligands (Tab = 4-(trimethylammonio)benzenethiolate), denoted as [Ag22(Tab)24](PF6)20·16CH3OH·6Et2O (Ag22·16CH3OH·6Et2O), alongside an Ag(I) cluster [Ag20(Tab)12(PhCOO)10(MeCN)2(H2O)](PF6)10·11MeCN (Ag20·11MeCN). Ag22 has a distinct hierarchical supratetrahedral structure with a central {Ag6} kernel surrounded by four [Ag4(Tab)6]4+ units. High-resolution electrospray ionization mass spectra demonstrate that Ag22 has two free electrons, indicating a superatomic core. Ag20 has a drum-like [Ag12(Tab)6(PhCOO)6(H2O)]6+ inner core capped by two tetrahedral-like [Ag4(Tab)3(PhCOO)2(MeCN)]2+ units. Ag20 can be transformed into Ag22 after its reaction with NaBH4 in solution. Antibacterial measurements reveal that Ag22 has a significantly lower minimum inhibitory concentration than that of the Ag20 cluster. This work not only extends the stabilization of silver(0/I) clusters to neutral thiol ligands but also offers new materials for the development of novel antibacterial materials.

17.
Bioorg Chem ; 142: 106925, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37890213

RESUMO

Thirty new tricyclicmatrinic derivatives were successively synthesized and evaluated for their inhibitory activity on the accumulation of triglycerides (TG) in AML12 cells, using 12 N-m-trifluoromethylbenzenesulfonyl matrine (1) as the hit compound. Among the analogues, compound 7n possessing 11-trimethylbutylamine quaternary exerted the highest in vitro TG-lowering potency, as well as a good safety profile. 7n significantly attenuated the hepatic injury and steatosis, and ameliorated dyslipidemia and dysglycemia in the mice with non-alcoholic fatty liver disease (NAFLD) induced by a high-fat diet. Primary mechanism study revealed that upregulation of peroxisome proliferator-activated receptors α (PPARα)-carnitine palmitoyltransferase 1A (CPT1A) pathway mediated the efficacy of 7n. Our study provides powerful information for developing this kind of compound into a new class of anti-NAFLD candidates, and compound 7n is worthy of further investigation as an ideal lead compound.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Matrinas , Triglicerídeos/metabolismo , Fígado/metabolismo , PPAR alfa/metabolismo , Camundongos Endogâmicos C57BL
18.
Int J Med Sci ; 21(10): 2000-2010, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39113881

RESUMO

Purpose: To study the effects of prior pelvic radiotherapy on bone marrow suppression in recurrent cervical cancer patients during chemotherapy. Methods and materials: The cases of 129 patients with recurrent cervical cancer were reviewed, of which 77 patients had pelvic radiotherapy history and another 52 patients with no pelvic radiotherapy history were used as control group. All patients received a chemotherapy regimen of paclitaxel combined with carboplatin (TC) per 21 days for 5-6 times. Hematologic toxicity, including count of red blood cell, white blood cell and neutrophil cell and platelet, was defined by using Common Terminology Criteria for Adverse Events (version 4.0). The relationship between age, body mass index, disease free survival, pathological types, FIGO stages, radiotherapy methods and the degree of bone marrow suppression during chemotherapy was statistically analyzed, respectively, for all recurrent cervical cancer patients. Results: Among 77 patients with previous radiotherapy history, 73 recurrent patients (94.8%) had bone marrow suppression followed by chemotherapy. Recurrent cervical cancer patients without prior radiotherapy (n=52) showed a lower risk of bone marrow suppression followed by chemotherapy (n=39, 75.0%, P < 0.05). The probability of severe bone marrow suppression (grade III-IV) after chemotherapy in recurrent cervical patients with or without history of radiotherapy was 41.6% and 13.5%, respectively (P < 0.05). In univariate analysis, radiotherapy methods were associated with the incidence of grade III-IV bone marrow suppression in recurrent cervical cancer patients (P=0.005). In multivariate analysis, radiotherapy methods and extended-field radiotherapy were the risk factor of grade III-IV bone marrow suppression (χ2=16.975, P=0.001). No significant differences in the counts of white blood cell, hemoglobin and platelet were observed before chemotherapy at relapse between patients with and without prior radiotherapy. Reduction of white blood cell counts, absolute value of neutrophil cell and platelet counts composited majority type of grade III and IV bone marrow suppression. Conclusions: The prior pelvic radiotherapy significantly increased the incidence of bone marrow suppression during chemotherapy in recurrent cervical cancer patients. When treating recurrent cervical cancer patients with chemotherapy who had prior radiotherapy, especially for those experienced external beam radiation therapy, essential attention and timely intervention are recommended to ensure completion of chemotherapy and clinical efficacy.


Assuntos
Medula Óssea , Recidiva Local de Neoplasia , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/tratamento farmacológico , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Medula Óssea/efeitos da radiação , Medula Óssea/efeitos dos fármacos , Medula Óssea/patologia , Adulto , Idoso , Carboplatina/administração & dosagem , Carboplatina/uso terapêutico , Carboplatina/efeitos adversos , Paclitaxel/administração & dosagem , Paclitaxel/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Pelve/efeitos da radiação , Pelve/patologia , Estudos Retrospectivos , Intervalo Livre de Doença
19.
J Nanobiotechnology ; 22(1): 623, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39402578

RESUMO

Gliomas are one of the most frequent primary brain tumors and pose a serious threat to people's lives and health. Platelets, a crucial component of blood, have been applied as drug delivery carriers for disease diagnosis and treatment. In this study, we designed engineered nanoplatelets for targeted delivery of therapeutic miR-375 and temozolomide (TMZ, a first-line glioma treatment agent) to enhance glioma therapy. Nanoplatelets were prepared through mild ultrasound, TMZ and miR-375 were co-loaded through ultrasound and electrostatic interactions, respectively, to combine chemotherapy with gene therapy against glioma. To improve the blood brain barrier (BBB) crossing efficiency and glioma targeting ability, the nanoplatelets were modified with central nervous system-specific rabies viral glycoprotein peptide (RVG) through thiol-maleimide click reaction. The RVG modified nanoplatelets co-loaded TMZ and miR-375 (NR/TMZ/miR-375) not only inherited the good stability and remarkable biocompatibility of platelets, but also promoted the cellular uptake and penetration of glioma tissues, and effectively induced cell apoptosis to enhance the therapeutic effect of drugs. In vivo studies showed that NR/TMZ/miR-375 significantly increased the circulation time of TMZ, and exhibited superior combined antitumor effects. In summary, this multifunctional 'natural' nanodrug delivery system provides a potent, scalable, and safety approach for platelet-based combined cancer chemotherapy and gene therapy.


Assuntos
Neoplasias Encefálicas , Sistemas de Liberação de Medicamentos , Glioma , MicroRNAs , Temozolomida , Temozolomida/farmacologia , Temozolomida/química , MicroRNAs/genética , Glioma/tratamento farmacológico , Animais , Humanos , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Camundongos , Sistemas de Liberação de Medicamentos/métodos , Camundongos Nus , Barreira Hematoencefálica/metabolismo , Nanopartículas/química , Apoptose/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Portadores de Fármacos/química , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/química , Glicoproteínas , Fragmentos de Peptídeos , Proteínas Virais
20.
Ophthalmic Res ; 67(1): 211-220, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38484716

RESUMO

INTRODUCTION: This study aimed to compare retinal vascular parameters and density in patients with moyamoya disease using the optical coherence tomography angiography. METHODS: This clinical trial totally enrolls 78 eyes from 39 participants, and all these patients with moyamoya disease (N = 13) are set as experimental group and participants with health who matched with age and gender are considered as the control group (N = 26). Then all these participants receive optical coherence tomography angiography detection. Participants' general data are collected and analyzed. Skeleton density (SD) value, vessel density (VD) value, fractal dimension (FD) value, vessel diameter index (VDI) value, foveal avascular zone (FAZ) value are analyzed. RESULTS: A total of 39 participants are included in this study. The SD value in the experimental group was significantly lower than that in control group (0.175 [0.166, 0.181] vs. 0.184 [0.175, 0.188], p = 0.017). Similarly, the VD value in the experimental group was significantly lower than that in the control group (0.333 [0.320, 0.350] vs. 0.354 [0.337, 0.364], p = 0.024). Additionally, the FD value in the experimental group was significantly lower than that in the control group (2.088 [2.083, 2.094] vs. 2.096 [2.090, 2.101], p = 0.022). As for the VDI and FAZ, VDI and FAZ values in the experimental group were lower than those in the control group, there was no significant difference in VDI and FAZ values between the two groups. CONCLUSIONS: Our study, using non-invasive and rapid OCTA imaging, confirmed decreased retinal vascular parameters and density in patients with moyamoya disease.


Assuntos
Angiofluoresceinografia , Fundo de Olho , Doença de Moyamoya , Vasos Retinianos , Tomografia de Coerência Óptica , Humanos , Doença de Moyamoya/diagnóstico , Doença de Moyamoya/fisiopatologia , Doença de Moyamoya/diagnóstico por imagem , Feminino , Masculino , Vasos Retinianos/diagnóstico por imagem , Vasos Retinianos/patologia , Tomografia de Coerência Óptica/métodos , Estudos Retrospectivos , Angiofluoresceinografia/métodos , Adulto , Pessoa de Meia-Idade , Acuidade Visual , Adulto Jovem , Adolescente , Seguimentos
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