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1.
Proc Natl Acad Sci U S A ; 121(28): e2401579121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38968123

RESUMO

Iron is an essential element for life owing to its ability to participate in a diverse array of oxidation-reduction reactions. However, misregulation of iron-dependent redox cycling can also produce oxidative stress, contributing to cell growth, proliferation, and death pathways underlying aging, cancer, neurodegeneration, and metabolic diseases. Fluorescent probes that selectively monitor loosely bound Fe(II) ions, termed the labile iron pool, are potentially powerful tools for studies of this metal nutrient; however, the dynamic spatiotemporal nature and potent fluorescence quenching capacity of these bioavailable metal stores pose challenges for their detection. Here, we report a tandem activity-based sensing and labeling strategy that enables imaging of labile iron pools in live cells through enhancement in cellular retention. Iron green-1 fluoromethyl (IG1-FM) reacts selectively with Fe(II) using an endoperoxide trigger to release a quinone methide dye for subsequent attachment to proximal biological nucleophiles, providing a permanent fluorescent stain at sites of elevated labile iron. IG1-FM imaging reveals that degradation of the major iron storage protein ferritin through ferritinophagy expands the labile iron pool, while activation of nuclear factor-erythroid 2-related factor 2 (NRF2) antioxidant response elements (AREs) depletes it. We further show that lung cancer cells with heightened NRF2 activation, and thus lower basal labile iron, have reduced viability when treated with an iron chelator. By connecting labile iron pools and NRF2-ARE activity to a druggable metal-dependent vulnerability in cancer, this work provides a starting point for broader investigations into the roles of transition metal and antioxidant signaling pathways in health and disease.


Assuntos
Elementos de Resposta Antioxidante , Ferro , Humanos , Ferro/metabolismo , Corantes Fluorescentes/química , Fator 2 Relacionado a NF-E2/metabolismo , Ferritinas/metabolismo , Estresse Oxidativo , Oxirredução , Linhagem Celular Tumoral , Antioxidantes/metabolismo
2.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38725156

RESUMO

Protein acetylation is one of the extensively studied post-translational modifications (PTMs) due to its significant roles across a myriad of biological processes. Although many computational tools for acetylation site identification have been developed, there is a lack of benchmark dataset and bespoke predictors for non-histone acetylation site prediction. To address these problems, we have contributed to both dataset creation and predictor benchmark in this study. First, we construct a non-histone acetylation site benchmark dataset, namely NHAC, which includes 11 subsets according to the sequence length ranging from 11 to 61 amino acids. There are totally 886 positive samples and 4707 negative samples for each sequence length. Secondly, we propose TransPTM, a transformer-based neural network model for non-histone acetylation site predication. During the data representation phase, per-residue contextualized embeddings are extracted using ProtT5 (an existing pre-trained protein language model). This is followed by the implementation of a graph neural network framework, which consists of three TransformerConv layers for feature extraction and a multilayer perceptron module for classification. The benchmark results reflect that TransPTM has the competitive performance for non-histone acetylation site prediction over three state-of-the-art tools. It improves our comprehension on the PTM mechanism and provides a theoretical basis for developing drug targets for diseases. Moreover, the created PTM datasets fills the gap in non-histone acetylation site datasets and is beneficial to the related communities. The related source code and data utilized by TransPTM are accessible at https://www.github.com/TransPTM/TransPTM.


Assuntos
Redes Neurais de Computação , Processamento de Proteína Pós-Traducional , Acetilação , Biologia Computacional/métodos , Bases de Dados de Proteínas , Software , Algoritmos , Humanos , Proteínas/química , Proteínas/metabolismo
3.
Plant Cell ; 34(7): 2747-2764, 2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35385118

RESUMO

Many glycine-rich RNA-binding proteins (GR-RBPs) have critical functions in RNA processing and metabolism. Here, we describe a role for the tomato (Solanum lycopersicum) GR-RBP SlRBP1 in regulating mRNA translation. We found that SlRBP1 knockdown mutants (slrbp1) displayed reduced accumulation of total chlorophyll and impaired chloroplast ultrastructure. These phenotypes were accompanied by deregulation of the levels of numerous key transcripts associated with chloroplast functions in slrbp1. Furthermore, native RNA immunoprecipitation-sequencing (nRIP-seq) recovered 61 SlRBP1-associated RNAs, most of which are involved in photosynthesis. SlRBP1 binding to selected target RNAs was validated by nRIP-qPCR. Intriguingly, the accumulation of proteins encoded by SlRBP1-bound transcripts, but not the mRNAs themselves, was reduced in slrbp1 mutants. Polysome profiling followed by RT-qPCR assays indicated that the polysome occupancy of target RNAs was lower in slrbp1 plants than in wild-type. Furthermore, SlRBP1 interacted with the eukaryotic translation initiation factor SleIF4A2. Silencing of SlRBP1 significantly reduced SleIF4A2 binding to SlRBP1-target RNAs. Taking these observations together, we propose that SlRBP1 binds to and channels RNAs onto the SleIF4A2 translation initiation complex and promotes the translation of its target RNAs to regulate chloroplast functions.


Assuntos
Solanum lycopersicum , Cloroplastos/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Solanum lycopersicum/genética , Fotossíntese/genética , Polirribossomos/metabolismo
4.
Nano Lett ; 24(28): 8679-8686, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38949784

RESUMO

The simultaneous detection of the orbital angular momentum (OAM) and wavelength offers new opportunities for optical multiplexing. However, because of the dispersion of lens functions for Fourier transformation, the mode conversions at distinct wavelengths cannot be achieved in the same plane. Here we propose an ultracompact achromatic complementary metal oxide semiconductor (CMOS)-integrated OAM mode detector. Specifically, a spatial multiplexed scheme, randomly interleaving the phase distributions for distributing the superposed OAM modes into preset positions at distinct wavelengths, is presented. In addition, such a nanoprinted achromatic OAM detector featuring a microscale size and a short focal length can be integrated onto a CMOS chip. Consequently, the four-bit incident light beams at three discrete wavelengths (633, 532, and 488 nm) can be distinguished with a high degree of accuracy evaluated by the average standardized Euclidean distance of ∼0.75 between the analytical and target results. Our results showcase a miniaturized platform for achieving high-capacity information processing.

5.
Plant J ; 116(6): 1737-1747, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37694805

RESUMO

Dicer-like (DCL) proteins are principal components of RNA silencing, a major defense mechanism against plant virus infections. However, their functions in suppressing virus-induced disease phenotypes remain largely unknown. Here, we identified a role for tomato (Solanum lycopersicum) DCL2b in regulating the wiry leaf phenotype during defense against tobacco mosaic virus (TMV). Knocking out SlyDCL2b promoted TMV accumulation in the leaf primordium, resulting in a wiry phenotype in distal leaves. Biochemical and bioinformatics analyses showed that 22-nt virus-derived small interfering RNAs (vsiRNAs) accumulated less abundantly in slydcl2b mutants than in wild-type plants, suggesting that SlyDCL2b-dependent 22-nt vsiRNAs are required to exclude virus from leaf primordia. Moreover, the wiry leaf phenotype was accompanied by upregulation of Auxin Response Factors (ARFs), resulting from a reduction in trans-acting siRNAs targeting ARFs (tasiARFs) in TMV-infected slydcl2b mutants. Loss of tasiARF production in the slydcl2b mutant was in turn caused by inhibition of miRNA390b function. Importantly, silencing SlyARF3 and SlyARF4 largely restored the wiry phenotype in TMV-infected slydcl2b mutants. Our work exemplifies the complex relationship between RNA viruses and the endogenous RNA silencing machinery, whereby SlyDCL2b protects the normal development of newly emerging organs by excluding virus from these regions and thus maintaining developmental silencing.


Assuntos
Vírus de Plantas , Solanum lycopersicum , Vírus do Mosaico do Tabaco , Vírus do Mosaico do Tabaco/fisiologia , Solanum lycopersicum/genética , Vírus de Plantas/genética , RNA Interferente Pequeno/genética , Ácidos Indolacéticos , Folhas de Planta/genética , Fenótipo , Doenças das Plantas
6.
Biol Reprod ; 110(3): 521-535, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38145497

RESUMO

Vitamin D receptors and vitamin D3-metabolizing enzymes have been found to be highly expressed in the ovaries and spermatophores of fish. However, the role of vitamin D3 on fish gonadal development has rarely been reported. In this study, 2-month-old female zebrafish were fed with different concentrations of vitamin D3 diets (0, 700, 1400, and 11 200 IU/kg) to investigate the effects of vitamin D3 on ovarian development. The diet with 0 IU/kg vitamin D3 resulted in elevated interstitial spaces, follicular atresia, and reproductive toxicity in zebrafish ovaries. Supplementation with 700 and 1400 IU/kg of vitamin D3 significantly increased the oocyte maturation rate; upregulated ovarian gonadal steroid hormone synthesis capacity; and elevated plasma estradiol, testosterone, and ovarian vitellogenin levels. Furthermore, the current study identified a vitamin D response element in the cyp19a1a promoter and demonstrated that 1.25(OH)2D3-vitamin D response directly activated cyp19a1a production through activating the vitamin D response element. In conclusion, this study shows that an appropriate concentration of vitamin D3 can promote zebrafish ovarian development and affect vitellogenin synthesis through the vdr/cyp19a1a/er/vtg gene axis.


Assuntos
Colecalciferol , Peixe-Zebra , Animais , Feminino , Colecalciferol/farmacologia , Vitelogeninas/genética , Atresia Folicular , Vitamina D , Hormônios Esteroides Gonadais , Oócitos
7.
Brief Bioinform ; 23(6)2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36198668

RESUMO

Sarcopenia is correlated with poor clinical outcomes in breast cancer (BC) patients. However, there is no precise quantitative study on the correlation between body composition changes and BC metastasis and survival. The present study proposed a deep learning radiomics (DLR) approach to investigate the effects of muscle and fat on distant metastasis and death outcomes in BC patients. Image feature extraction was performed on 4th thoracic vertebra (T4) and 11th thoracic vertebra (T11) on computed tomography (CT) image levels by DLR, and image features were combined with clinical information to predict distant metastasis in BC patients. Clinical information combined with DLR significantly predicted distant metastasis in BC patients. In the test cohort, the area under the curve of model performance on clinical information combined with DLR was 0.960 (95% CI: 0.942-0.979, P < 0.001). The patients with distant metastases had a lower pectoral muscle index in T4 (PMI/T4) than in patients without metastases. PMI/T4 and visceral fat tissue area in T11 (VFA/T11) were independent prognostic factors for the overall survival in BC patients. The pectoralis muscle area in T4 (PMA/T4) and PMI/T4 is an independent prognostic factor for distant metastasis-free survival in BC patients. The current study further confirmed that muscle/fat of T4 and T11 levels have a significant effect on the distant metastasis of BC. Appending the network features of T4 and T11 to the model significantly enhances the prediction performance of distant metastasis of BC, providing a valuable biomarker for the early treatment of BC patients.


Assuntos
Neoplasias da Mama , Aprendizado Profundo , Humanos , Feminino , Neoplasias da Mama/patologia , Tomografia Computadorizada por Raios X/métodos , Estudos de Coortes , Músculos/patologia
8.
Nat Mater ; 22(7): 903-912, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36759564

RESUMO

The surge of fast-spreading SARS-CoV-2 mutated variants highlights the need for fast, broad-spectrum strategies to counteract viral infections. In this work, we report a physical barrier against SARS-CoV-2 infection based on an inhalable bioadhesive hydrogel, named spherical hydrogel inhalation for enhanced lung defence (SHIELD). Conveniently delivered via a dry powder inhaler, SHIELD particles form a dense hydrogel network that coats the airway, enhancing the diffusional barrier properties and restricting virus penetration. SHIELD's protective effect is first demonstrated in mice against two SARS-CoV-2 pseudo-viruses with different mutated spike proteins. Strikingly, in African green monkeys, a single SHIELD inhalation provides protection for up to 8 hours, efficiently reducing infection by the SARS-CoV-2 WA1 and B.1.617.2 (Delta) variants. Notably, SHIELD is made with food-grade materials and does not affect normal respiratory functions. This approach could offer additional protection to the population against SARS-CoV-2 and other respiratory pathogens.


Assuntos
COVID-19 , Animais , Chlorocebus aethiops , Camundongos , SARS-CoV-2 , Hidrogéis , Primatas
9.
Hum Reprod ; 39(1): 43-52, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37994690

RESUMO

STUDY QUESTION: What is the impact of male hepatitis B virus (HBV) infection on sperm quality, embryonic development, and assisted reproductive outcomes? SUMMARY ANSWER: Male HBV infection did not affect assisted reproductive outcomes, but HBV is capable of impairing human sperm and embryo formation in the early stages following fertilization. WHAT IS KNOWN ALREADY: HBV is found in germ cells and early embryos of patients with HBV. HBV may impair human sperm function via increasing reactive oxygen species. STUDY DESIGN, SIZE, DURATION: We conducted a retrospective cohort study of 1581 infertile couples, including 496 male patients clinically confirmed to have hepatitis B infection, and a laboratory study of effects of HBV proteins on early embryos, using human embryonic stem cells (hESCs), human sperm, and golden hamster oocytes. PARTICIPANTS/MATERIALS, SETTING, METHODS: In total, 1581 infertile couples (24-40 years of age) who were admitted to a reproductive medicine center to undergo ART for the first time from January 2019 to November 2021 were selected as the study subjects. The case group was composed of 469 couples with hepatitis B surface antigen (HBsAg)-seropositive men and seronegative women (368 for IVF and 101 for ICSI treatment). The negative control group was composed of 1112 couples where both men and women were seronegative for hepatitis B antigen. We divided these couples into three comparison groups (IVF/ICSI, IVF, and ICSI). IVF of human sperm and hamster oocytes was used to evaluate the influence of the HBV HBs protein on formation of 2-cell embryos. Mitochondrial membrane potential (MMP) of hESCs was assayed via a fluorescence intensity system. Immunofluorescence staining of the phosphorylated histone H2A.X was applied to identify DNA damage to hESCs caused by the HBV X (HBx) protein. MAIN RESULTS AND THE ROLE OF CHANCE: Sperm concentration, total sperm number, and sperm with normal morphology were decreased in the couples with HBV-infected males in couples who were undergoing IVF/ICSI (male HBV(+) vs control: 469 vs 1112 individuals; sperm number, P < 0.01; normal sperm morphology, P < 0.01), IVF (368 vs 792; sperm number, P < 0.01; normal sperm morphology, P ≤ 0.05), and ICSI (101 vs 306; sperm number, P < 0.01; normal sperm morphology, P < 0.001). There was no significant difference in the number of embryo cleavages, blastocyst formation, biochemical pregnancy rate, clinical pregnancy rate, and live-birth rate between case and control groups. The 2PN fertilization rate in IVF/ICSI (P < 0.01) and ICSI (P < 0.05) couples, and the number of 2PN-fertilized oocytes in IVF (P < 0.001) couples were lower in couples with male HBV infection compared to control couples. HBV HBs protein reduced the MMP of human sperm and decreased 2-cell embryo formation in IVF of human sperm and zona-free-hamster oocyte. A reduction in fluorescence intensity and immunofluorescence staining of phosphorylated histone H2A.X indicated that HBx caused MMP impairment and DNA damage in human early embryonic cells, respectively. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: HBV can be examined in samples of sperm or discarded IVF early embryos from HBsAg-seropositive men and seronegative women. The hESC model in vitro may not fully mimic the natural embryos in vivo. WIDER IMPLICATIONS OF THE FINDINGS: This study furthers our understanding of the influence of male HBV infection on embryonic development. Our results suggest that a semen-washing process may be necessary for male patients with HBV undergoing ART to minimize the potential negative effects of HBV infection on the early embryo. STUDY FUNDING/COMPETING INTEREST(S): This work was funded by grants from the National Natural Science Foundation of China, grant numbers 81870432 and 81570567 to X.Z., 81571994 to P.S., and 81950410640, the Natural Science Foundation of Guangdong Province, China (No. 2023A1515010660 to X.Z.), and the Li Ka Shing Shantou University Foundation (Grant No. L11112008). The authors have no conflicts of interest.


Assuntos
Vírus da Hepatite B , Hepatite B , Gravidez , Humanos , Masculino , Feminino , Fertilização in vitro , Injeções de Esperma Intracitoplásmicas , Estudos Retrospectivos , Sêmen , Antígenos de Superfície da Hepatite B , Histonas , Taxa de Gravidez , Desenvolvimento Embrionário , Espermatozoides
10.
Mol Psychiatry ; 28(4): 1611-1621, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36914812

RESUMO

Clinical and animal studies have shown that gut microbiome disturbances can affect neural function and behaviors via the microbiota-gut-brain axis, and may be implicated in the pathogenesis of several brain diseases. However, exactly how the gut microbiome modulates nervous system activity remains obscure. Here, using a single-cell nucleus sequencing approach, we sought to characterize the cell type-specific transcriptomic changes in the prefrontal cortex and hippocampus derived from germ-free (GF), specific pathogen free, and colonized-GF mice. We found that the absence of gut microbiota resulted in cell-specific transcriptomic changes. Furthermore, microglia transcriptomes were preferentially influenced, which could be effectively reversed by microbial colonization. Significantly, the gut microbiome modulated the mutual transformation of microglial subpopulations in the two regions. Cross-species analysis showed that the transcriptome changes of these microglial subpopulations were mainly associated with Alzheimer's disease (AD) and major depressive disorder (MDD), which were further supported by animal behavioral tests. Our findings demonstrate that gut microbiota mainly modulate the mutual transformation of microglial subtypes, which may lead to new insights into the pathogenesis of AD and MDD.


Assuntos
Doença de Alzheimer , Transtorno Depressivo Maior , Microbioma Gastrointestinal , Camundongos , Animais , Microbioma Gastrointestinal/fisiologia , Microglia , Depressão , Córtex Pré-Frontal
11.
Circ Res ; 131(10): e135-e150, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-36252111

RESUMO

BACKGROUND: Mesenchymal stem cell (MSC)-derived exosomes are well recognized immunomodulating agents for cardiac repair, while the detailed mechanisms remain elusive. The Pericardial drainage pathway provides the heart with immunosurveillance and establishes a simplified model for studying the mechanisms underlying the immunomodulating effects of therapeutic exosomes. METHODS: Myocardial infarction (MI) models with and without pericardiectomy (corresponding to Tomy MI and NonTomy MI) were established to study the functions of pericardial drainage pathway in immune activation of cardiac-draining mediastinal lymph node (MLN). Using the NonTomy MI model, MSC exosomes or vehicle PBS was intrapericardially injected for MI treatment. Via cell sorting and RNA-seq (RNA-sequencing) analysis, the differentially expressed genes were acquired for integrated pathway analysis to identify responsible mechanisms. Further, through functional knockdown/inhibition studies, application of cytokines and neutralizing antibodies, western blot, flow cytometry, and cytokine array, the molecular mechanisms were studied. In addition, the therapeutic efficacy of intrapericardially injected exosomes for MI treatment was evaluated through functional and histological analyses. RESULTS: We show that the pericardial draining pathway promoted immune activation in the MLN following MI. Intrapericardially injected exosomes accumulated in the MLN and induced regulatory T cell differentiation to promote cardiac repair. Mechanistically, uptake of exosomes by major histocompatibility complex (MHC)-II+ antigen-presenting cells (APCs) induced Foxo3 activation via the protein phosphatase (PP)-2A/p-Akt/forkhead box O3 (Foxo3) pathway. Foxo3 dominated APC cytokines (IL-10, IL-33, and IL-34) expression and built up a regulatory T cell (Treg)-inducing niche in the MLN. The differentiation of Tregs as well as their cardiac deployment were elevated, which contributed to cardiac inflammation resolution and cardiac repair. CONCLUSIONS: This study reveals a novel mechanism underlying the immunomodulation effects of MSC exosomes and provides a promising candidate (PP2A/p-Akt/Foxo3 signaling pathway) with a favorable delivery route (intrapericardial injection) for cardiac repair.


Assuntos
Exossomos , Traumatismos Cardíacos , Células-Tronco Mesenquimais , Infarto do Miocárdio , Humanos , Exossomos/metabolismo , Proteína Forkhead Box O3/genética , Proteína Forkhead Box O3/metabolismo , Células-Tronco Mesenquimais/metabolismo , Infarto do Miocárdio/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Traumatismos Cardíacos/metabolismo
12.
Phys Chem Chem Phys ; 26(12): 9462-9474, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38446428

RESUMO

In this work, a dielectric metasurface composed of a silicon nanodisk etched with a square hole is proposed. By introducing C4v symmetry breaking, the symmetry-protected bound states in the continuum (SP-BIC) is transformed into a quasi-BIC (Q-BIC), simultaneously inducing triple Fano resonances in the near-infrared light band corresponding to one dipole and two Q-BIC resonances. The characteristics of Q-BIC resonances are elucidated through multipole decomposition and near-field distribution analysis. Subsequently, monolayer graphene is integrated into the Si metasurface. The light field in the composite metasurface can be flexibly modulated by changing the Fermi level of graphene. This modulation enables optimal transmission with an enhancement of up to 252%, while the confined electromagnetic energy experiences a remarkable increase of about 1020%. Simulation results demonstrate that the Si-graphene composite metasurface exhibits a high refractive index sensitivity of 162 nm RIU-1, accompanied by a figure of merit of 170.526 RIU-1. This composite metasurface holds promise as a high-performance sensor in the near-infrared band and has potential for application in the fields of active tunable optical devices and biochemical sensing.

13.
Surg Endosc ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958719

RESUMO

BACKGROUND: Laparoscopic pancreatoduodenectomy (LPD) is one of the most challenging operations and has a long learning curve. Artificial intelligence (AI) automated surgical phase recognition in intraoperative videos has many potential applications in surgical education, helping shorten the learning curve, but no study has made this breakthrough in LPD. Herein, we aimed to build AI models to recognize the surgical phase in LPD and explore the performance characteristics of AI models. METHODS: Among 69 LPD videos from a single surgical team, we used 42 in the building group to establish the models and used the remaining 27 videos in the analysis group to assess the models' performance characteristics. We annotated 13 surgical phases of LPD, including 4 key phases and 9 necessary phases. Two minimal invasive pancreatic surgeons annotated all the videos. We built two AI models for the key phase and necessary phase recognition, based on convolutional neural networks. The overall performance of the AI models was determined mainly by mean average precision (mAP). RESULTS: Overall mAPs of the AI models in the test set of the building group were 89.7% and 84.7% for key phases and necessary phases, respectively. In the 27-video analysis group, overall mAPs were 86.8% and 71.2%, with maximum mAPs of 98.1% and 93.9%. We found commonalities between the error of model recognition and the differences of surgeon annotation, and the AI model exhibited bad performance in cases with anatomic variation or lesion involvement with adjacent organs. CONCLUSIONS: AI automated surgical phase recognition can be achieved in LPD, with outstanding performance in selective cases. This breakthrough may be the first step toward AI- and video-based surgical education in more complex surgeries.

14.
Appl Microbiol Biotechnol ; 108(1): 402, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951204

RESUMO

Delayed graft function (DGF) is a frequently observed complication following kidney transplantation (KT). Our prior research revealed dynamic shifts in salivary microbiota post-KT with immediate graft function (IGF), yet its behavior during DGF remains unexplored. Five recipients with DGF and 35 recipients with IGF were enrolled. Saliva samples were collected during the perioperative period, and 16S rRNA gene sequencing was performed. The salivary microbiota of IGFs changed significantly and gradually stabilized with the recovery of renal function. The salivary microbiota composition of DGFs was significantly different from that of IGFs, although the trend of variation appeared to be similar to that of IGFs. Salivary microbiota that differed significantly between patients with DGF and IGF at 1 day after transplantation were able to accurately distinguish the two groups in the randomForest algorithm (accuracy = 0.8333, sensitivity = 0.7778, specificity = 1, and area under curve = 0.85), with Selenomonas playing an important role. Bacteroidales (Spearman's r = - 0.4872 and p = 0.0293) and Veillonella (Spearmen's r = - 0.5474 and p = 0.0125) were significantly associated with the serum creatinine in DGF patients. Moreover, the significant differences in overall salivary microbiota structure between DGF and IGF patients disappeared upon long-term follow-up. This is the first study to investigate the dynamic changes in salivary microbiota in DGFs. Our findings suggested that salivary microbiota was able to predict DGF in the early stages after kidney transplantation, which might help the perioperative clinical management and early-stage intervention of kidney transplant recipients. KEY POINTS: • Salivary microbiota on the first day after KT could predict DGF. • Alterations in salivary taxa after KT are related to recovery of renal function.


Assuntos
Função Retardada do Enxerto , Transplante de Rim , Microbiota , RNA Ribossômico 16S , Saliva , Humanos , Transplante de Rim/efeitos adversos , Saliva/microbiologia , Masculino , Feminino , Pessoa de Meia-Idade , RNA Ribossômico 16S/genética , Adulto , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/genética
15.
Eur Heart J ; 44(19): 1748-1760, 2023 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-36916305

RESUMO

AIMS: Epicardium and epicardium-derived cells are critical players in myocardial fibrosis. Mesenchymal stem cell-derived extracellular vesicles (EVs) have been studied for cardiac repair to improve cardiac remodelling, but the actual mechanisms remain elusive. The aim of this study is to investigate the mechanisms of EV therapy for improving cardiac remodelling and develop a promising treatment addressing myocardial fibrosis. METHODS AND RESULTS: Extracellular vesicles were intrapericardially injected for mice myocardial infarction treatment. RNA-seq, in vitro gain- and loss-of-function experiments, and in vivo studies were performed to identify targets that can be used for myocardial fibrosis treatment. Afterward, a lipid nanoparticle-based long non-coding RNA (lncRNA) therapy was prepared for mouse and porcine models of myocardial infarction treatment. Intrapericardial injection of EVs improved adverse myocardial remodelling in mouse models of myocardial infarction. Mechanistically, Tcf21 was identified as a potential target to improve cardiac remodelling. Loss of Tcf21 function in epicardium-derived cells caused increased myofibroblast differentiation, whereas forced Tcf21 overexpression suppressed transforming growth factor-ß signalling and myofibroblast differentiation. LncRNA-Tcf21 antisense RNA inducing demethylation (TARID) that enriched in EVs was identified to up-regulate Tcf21 expression. Formulated lncRNA-TARID-laden lipid nanoparticles up-regulated Tcf21 expression in epicardium-derived cells and improved cardiac function and histology in mouse and porcine models of myocardial infarction. CONCLUSION: This study identified Tcf21 as a critical target for improving cardiac fibrosis. Up-regulating Tcf21 by using lncRNA-TARID-laden lipid nanoparticles could be a promising way to treat myocardial fibrosis. This study established novel mechanisms underlying EV therapy for improving adverse remodelling and proposed a lncRNA therapy for cardiac fibrosis.


Assuntos
Infarto do Miocárdio , RNA Longo não Codificante , Camundongos , Animais , Suínos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Antissenso/genética , RNA Antissenso/metabolismo , Remodelação Ventricular , Infarto do Miocárdio/genética , Infarto do Miocárdio/terapia , Infarto do Miocárdio/metabolismo , Fibrose , Desmetilação
16.
Sheng Li Xue Bao ; 76(2): 215-223, 2024 Apr 25.
Artigo em Zh | MEDLINE | ID: mdl-38658371

RESUMO

This study aimed to investigate the effects of microtubule associated tumor suppressor 1 (MTUS1) on hemeoxygenase 1 (HMOX1) expression and hemin-induced apoptosis of vascular endothelial cells and its regulatory mechanism. RNA sequencing, RT-qPCR and Western blot were used to assess altered genes of hemin binding proteins, the expression of cAMP response element-binding protein (CREB) and nuclear respiratory factor 2 (NRF2), hemin-induced HMOX1 expression in MTUS1 knockdown human umbilical vein endothelial cells (HUVEC), and the effect of overexpression of CREB and NRF2 on HMOX1 expression in MTUS1 knockdown 293T cells. The effect of MTUS1 or HMOX1 knockdown on hemin-induced apoptosis in HUVEC, and the overexpression of NRF2 on hemin-induced apoptosis in MTUS1 knockdown 293T cells were assayed with CCK8 and Western blot. The results showed that MTUS1 was knocked down significantly in HUVEC by siRNA (P < 0.01), accompanied by decreased HMOX1 expression (P < 0.01). The increased HMOX1 expression induced by hemin was also inhibited by MTUS1 knockdown (P < 0.01). And the apoptosis of HUVEC induced by hemin was amplified by MTUS1 or HMOX1 knockdown (P < 0.01). Moreover the expression of CREB and NRF2 were both inhibited by MTUS1 knockdown in HUVEC (P < 0.01). The decreased HMOX1 regulated by MTUS1 knockdown could be rescued partly by overexpression of NRF2 (P < 0.01), however, not by overexpression of CREB. And the MTUS1 knockdown mediated decreased 293T cells viability induced by hemin could be partly rescued by NRF2 overexpression (P < 0.01). These results suggest that MTUS1 can inhibit hemin-induced apoptosis of HUVEC, and the mechanism maybe related to MTUS1/NRF2/HMOX1 pathway.


Assuntos
Apoptose , Heme Oxigenase-1 , Hemina , Células Endoteliais da Veia Umbilical Humana , Fator 2 Relacionado a NF-E2 , Humanos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Técnicas de Silenciamento de Genes , Heme Oxigenase-1/metabolismo , Heme Oxigenase-1/genética , Hemina/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/genética
17.
Oncologist ; 28(7): e575-e584, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35930304

RESUMO

BACKGROUND: Systemic chemotherapy is the primary treatment in patients with locally advanced or metastatic pancreatic ductal adenocarcinoma (PDAC). More effective treatment options are highly awaited. The aim of this study was to evaluate the toxicity and feasibility of gemcitabine/nab-paclitaxel/S-1 (GAS) chemotherapy on a 21-day cycle in patients with locally advanced or metastatic PDAC, determine the dose-limiting toxicity (DLT) and the maximum tolerated dose (MTD) of S-1 in this regimen, and explore preliminary efficacy. METHODS: Eligible patients with locally advanced or metastatic PDAC received GAS chemotherapy on a 21-day cycle. Fixed-dose nab-paclitaxel (125 mg/m2) and gemcitabine (1000 mg/m2) were given intravenously on days 1 and 8. Different doses of S-1 were given orally twice daily from day 1 to day 14 in a 3+3 dose escalation design. According to patients` body surface area, the dose-escalation design was as follows: patients with a body surface area of 1.25-1.5 m2 received S-1 40 mg/day initially and the dose was increased to 60 mg or 80 mg. Patients with a body surface area of more than 1.5 m2 received S-1 60 mg/day initially and the dose was increased to 80 mg or 100 mg. The primary endpoints were to evaluate the toxicity and determine the DLT and MTD of S-1. The secondary endpoint was to evaluate efficacy, including best objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS). adverse events (AEs) were evaluated according to the NCI-CTCAE 5.0. Tumor response was assessed using the RECIST 1.1. RESULTS: A total of 21 eligible patients were included. Due to the infrequence of patients with a body surface area of 1.25-1.5 m2, only 2 patients were included in cohort of S-1 40 mg. The dose-escalation for patients in this group failed to be enrolled completely. For patients with a body surface area of more than 1.5 m2, 3 DLTs in 7 patients were detected at cohort of S-1 100 mg (grade 3 thrombocytopenia with hemorrhage, grade 3 rash, and grade 3 mucositis/stomatitis). S-1 80 mg/day (body surface area: >1.5 m2) was considered to be the MTD in GAS chemotherapy on a 21-day cycle. No grade 4 AEs or treatment-related deaths were observed. The most commonly occurring hematologic AE of any grade was anemia (38.1%). The most frequent nonhematologic AEs of any grade were peripheral neuropathy (38.1%), dyspepsia (23.8%), constipation (23.8%), and alopecia (23.8%). Response assessment showed that the best ORR was 36.8% (7 of 19 patients) and the DCR was 94.7% (18 of 19 patients). The median PFS was 5.3 (95% CI, 4.6 to 6.0) months and the median OS was 10.3 (95% CI, 8.1 to 12.5) months. CONCLUSION: GAS chemotherapy (21-day cycle) with nab-paclitaxel 125 mg/m2, gemcitabine 1000 mg/m2, and S-1 80 mg/day (body surface area: >1.5 m2) was found to have acceptable toxicity and significant clinical control in patients with locally advanced or metastatic PDAC. We conclude that further trials with this combination are warranted. (Trial Identifier: ChiCTR1900027833 [chictr.org]).


Assuntos
Adenocarcinoma , Gencitabina , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Paclitaxel , Adenocarcinoma/patologia , Neoplasias Pancreáticas
18.
Biochem Biophys Res Commun ; 646: 96-102, 2023 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-36708596

RESUMO

With rapid development of liver transplantation technology, the demand for transplants have reached beyond the supply of organs, and thus development of effective strategies to reduce cold ischemia injury in fatty liver is important. Here, we explored the potential effect of SGLT-2 inhibitor in cold ischemia injury, fatty livers from 2 weeks methionine and choline deficient diet (MCD) rats were administered. After one week of intragastric administration of Sodium-dependent glucose transporters (SGLT-2) inhibitor empagliflozin (EMPA) or NaCI, liver were stored for 24 h. The results showed that EMPA could significantly reduce the cold ischemic injury in the mitochondria of fatty liver. To explore the mechanism, signal transducers and activators of transcription 3(STAT3) inhibitor AG490 group was used in a similar manner. We detected the changes in p-signal transducers and activators of transcription 3 (P-STAT3), alcohol-dehydrogenase 2 (ALDH2) and degree of apoptosis in three distinct groups. The results suggested that the protein expression of P-STAT3 and ALDH2 was higher in the EMPA group than in other two groups, whereas extent of apoptosis in the EMPA group was lower than other two groups. The data suggested that SGLT2 inhibitors could alleviate cold ischemia damage of mitochondria in fatty liver, which may be related to the inhibition of apoptosis and the activation of P-STAT3 and ALDH2.


Assuntos
Isquemia Fria , Fígado Gorduroso , Animais , Ratos , Fígado Gorduroso/metabolismo , Isquemia , Fígado/metabolismo , Transportador 2 de Glucose-Sódio
19.
Small ; 19(34): e2301998, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37162443

RESUMO

In order to overcome the limitations of supramolecular organic cages for their incomplete accessibility of active sites in the solid state and uneasy recyclability in liquid solution, herein a nitrogen-rich organic cage is rationally linked into framework systems and four isoreticular covalent organic frameworks (COFs), that is, Cage-TFB-COF, Cage-NTBA-COF, Cage-TFPB-COF, and Cage-TFPT-COF, are successfully synthesized. Structure determination reveals that they are all high-quality crystalline materials derived from the eclipsed packing of related isoreticular two-dimensional frameworks. Since the nitrogen-rich sites usually have a high affinity toward iodine species, iodine adsorption investigations are carried out and the results show that all of them display an enhancement in iodine adsorption capacities. Especially, Cage-NTBA-COF exhibits an iodine adsorption capacity of 304 wt%, 14-fold higher than the solid sample packed from the cage itself. The strong interactions between the nitrogen-rich sites and the adsorbed iodine species are revealed by spectral analyses. This work demonstrates that, utilizing the reticular chemistry strategy to extend the close-packed supramolecular organic cages into crystalline porous framework solids, their inherent properties can be greatly exploited for targeted applications.

20.
Small ; 19(31): e2207868, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36965080

RESUMO

Antibacterial photodynamic therapy (aPDT) is a promising antibiotics-alternative strategy for bacterial infectious diseases, which features broad-spectrum antibacterial activity with a low risk of inducing bacterial resistance. However, clinical applications of aPDT are still hindered by the hydrophobicity-caused inadequate photodynamic activity of conventional photosensitizers and the hypoxic microenvironment of bacterial infections. To address these problems, herein, a promising strategy is developed to achieve specific chemiluminescence (CL) imaging and enhanced PDT of bacterial infections using hemin-modified carbon dots (H-CDs). The H-CDs can be facilely prepared and exhibit favorable water solubility, augmented photodynamic activity, and unique peroxidase-mimicking capacity. Compared with the free CDs, the photodynamic efficacy of H-CDs is significantly augmented due to the increased electron-hole separation efficiency. Moreover, the peroxidase catalytic performance of H-CDs enables not only infection identification via bacterial infection microenvironment-responsive CL imaging but also oxygen self-supplied aPDT with hypoxia-relief-enhanced bacteria inactivation effects. Finally, the enhanced aPDT efficiencies of H-CDs are validated in both in vivo abscess and infected wound models. This work may provide an effective antibacterial platform for the selective imaging-guided treatment of bacterial infections.


Assuntos
Infecções Bacterianas , Fotoquimioterapia , Humanos , Fotoquimioterapia/métodos , Carbono , Hemina , Luminescência , Infecções Bacterianas/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
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