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1.
Phytomedicine ; 130: 155737, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38772183

RESUMO

BACKGROUND: Caenorhabditis elegans (C. elegans) has been recognized for being a useful model organism in small-molecule drug screens and drug efficacy investigation. However, there remain bottlenecks in evaluating such processes as drug uptake and distribution due to a lack of appropriate chemical tools. PURPOSE: This study aims to prepare fluorescence-labeled leonurine as an example to monitor drug uptake and distribution of small molecule in C. elegans and living cells. METHODS: FITC-conjugated leonurine (leonurine-P) was synthesized and characterized by LC/MS, NMR, UV absorption and fluorescence intensity. Leonurine-P was used to stain C. elegans and various mammalian cell lines. Different concentrations of leonurine were tested in conjunction with a competing parent molecule to determine whether leonurine-P and leonurine shared the same biological targets. Drug distribution was analyzed by imaging. Fluorometry in microplates and flow cytometry were performed for quantitative measurements of drug uptake. RESULTS: The UV absorption peak of leonurine-P was 490∼495 nm and emission peak was 520 nm. Leonurine-P specifically bound to endogenous protein targets in C. elegans and mammalian cells, which was competitively blocked by leonurine. The highest enrichment levels of leonurine-P were observed around 72 h following exposure in C. elegans. Leonurine-P can be used in a variety of cells to observe drug distribution dynamics. Flow cytometry of stained cells can be facilely carried out to quantitatively detect probe signals. CONCLUSIONS: The strategy of fluorescein-labeled drugs reported herein allows quantification of drug enrichment and visualization of drug distribution, thus illustrates a convenient approach to study phytodrugs in pharmacological contexts.


Assuntos
Caenorhabditis elegans , Ácido Gálico , Animais , Ácido Gálico/análogos & derivados , Ácido Gálico/farmacocinética , Ácido Gálico/metabolismo , Humanos , Fluoresceína-5-Isotiocianato/análogos & derivados , Citometria de Fluxo , Fluorescência , Corantes Fluorescentes
2.
Bioconjug Chem ; 35(6): 737-743, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38738511

RESUMO

Radiation therapy is one of the most common treatments for cancer. However, enhancing tumors' radiation sensitivity and overcoming tolerance remain a challenge. Previous studies have shown that the Ras signaling pathway directly influences tumor radiation sensitivity. Herein, we designed a series of Ras-targeting stabilized peptides, with satisfactory binding affinity (KD = 0.13 µM with HRas) and good cellular uptake. Peptide H5 inhibited downstream phosphorylation of ERK and increased radio-sensitivity in HeLa cells, resulting in significantly reduced clonogenic survival. The stabilized peptides, designed with an N-terminal nucleation strategy, acted as potential radio-sensitizers and broadened the applications of this kind of molecule. This is the first report of using stabilized peptides as radio-sensitizers, broadening the applications of this kind of molecule.


Assuntos
Peptídeos , Tolerância a Radiação , Proteínas ras , Humanos , Peptídeos/química , Peptídeos/farmacologia , Células HeLa , Tolerância a Radiação/efeitos dos fármacos , Proteínas ras/metabolismo , Radiossensibilizantes/farmacologia , Radiossensibilizantes/química , Sobrevivência Celular/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/radioterapia
3.
Environ Pollut ; 351: 124081, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38697251

RESUMO

Microcystin-leucine arginine (MC-LR) is a common cyantotoxin produced by hazardous cyanobacterial blooms, and eutrophication is increasing the contamination level of MC-LR in drinking water supplies and aquatic foods. MC-LR has been linked to colorectal cancer (CRC) progression associated with tumor microenvironment, however, the underlying mechanism is not clearly understood. In present study, by using GEO, KEGG, GESA and ImmPort database, MC-LR related differentially expressed genes (DEGs) and pathway- and gene set-enrichment analysis were performed. Of the three identified DEGs (CXCL1, GUCA2A and GDF15), CXCL1 was shown a positive association with tumor infiltration, and was validated to have a dominantly higher upregulation in MC-LR-treated tumor-associated macrophages (TAMs) rather than in MC-LR-treated CRC cells. Both CRC cell/macrophage co-culture and xenograft mouse models indicated that MC-LR stimulated TAMs to secrete CXCL1 resulting in promoted proliferation, migration, and invasion capability of CRC cells. Furtherly, IP-MS assay found that interaction between TAMs-derived CXCL1 and CRC cell-derived IGHG1 may enhance CRC cell proliferation and migration after MC-LR treatment, and this effect can be attenuated by silencing IGHG1 in CRC cell. In addition, molecular docking analysis, co-immunoprecipitation and immunofluorescence further proved the interactions between CXCL1 and IGHG1. In conclusion, CXCL1 secreted by TAMs can trigger IGHG1 expression in CRC cells, which provides a new clue in elucidating the mechanism of MC-LR-mediated CRC progression.


Assuntos
Quimiocina CXCL1 , Neoplasias Colorretais , Transdução de Sinais , Macrófagos Associados a Tumor , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/genética , Humanos , Animais , Quimiocina CXCL1/genética , Quimiocina CXCL1/metabolismo , Camundongos , Macrófagos Associados a Tumor/metabolismo , Microcistinas/toxicidade , Toxinas Marinhas , Linhagem Celular Tumoral , Progressão da Doença , Proliferação de Células/efeitos dos fármacos , Microambiente Tumoral
4.
Sci Data ; 11(1): 546, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806531

RESUMO

For highly autonomous vehicles, human does not need to operate continuously vehicles. The brain-computer interface system in autonomous vehicles will highly depend on the brain states of passengers rather than those of human drivers. It is a meaningful and vital choice to translate the mental activities of human beings, essentially playing the role of advanced sensors, into safe driving. Quantifying the driving risk cognition of passengers is a basic step toward this end. This study reports the creation of an fNIRS dataset focusing on the prefrontal cortex activity in fourteen types of highly automated driving scenarios. This dataset considers age, sex and driving experience factors and contains the data collected from an 8-channel fNIRS device and the data of driving scenarios. The dataset provides data support for distinguishing the driving risk in highly automated driving scenarios via brain-computer interface systems, and it also provides the possibility of preventing potential hazards in some scenarios, in which risk remains at a high value for an extended period, before hazard occurs.


Assuntos
Condução de Veículo , Cognição , Adulto , Feminino , Humanos , Masculino , Automação , Interfaces Cérebro-Computador , Córtex Pré-Frontal/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho
5.
Front Microbiol ; 15: 1342356, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38550860

RESUMO

Introduction: The gut-liver axis has emerged as a focal point in chronic liver disorders, prompting more research into the role of the gut microbiota in liver cirrhosis. In individuals with liver cirrhosis, changes in the structure and function of the gut microbiota are closely tied to clinical prognosis. However, there is a scarcity of bibliometric evaluations conducted in this particular field. Methods: This study is aiming to conduct a complete analysis of the knowledge structure and centers pertaining to gut microbiota in liver cirrhosis using bibliometric methods. Publications on gut microbiota and liver cirrhosis from 2001 to 2023 are sourced from the Web of Science Core Collection. For the bibliometric analysis, we employ VOSviewer, CiteSpace, and the R package "bibliometrix". Results: Our study encompasses a comprehensive collection of 3109 articles originating from 96 countries, with notable contributions from leading nations such as the United States and China. The quantity of publications concerning the gut microbiota of liver cirrhosis rises annually. The University of California San Diego, Virginia Commonwealth University, Zhejiang University are the primary research institutions. World Journal of Gastroenterology publishes the most papers in this field, while hepatology is the most frequently co-cited journal. These publications come from a total of 15,965 authors, and the most prolific authors are Bajaj Jasmohan S., Schnabl Bernd and Gillevet Patrick M., while the most co-cited authors are Bajaj Jasmohan S., Younossi Zobair M., and Reiner Wiest. In addition, "dysbiosis", "gut microbiota", "intestinal barrier", "fecal microbiota transplantation", and "complement-system" are the primary keywords of research trends in recent years. Discussion: This study offering a comprehensive insight into the research dynamics surrounding gut microbiota in patients with liver cirrhosis. It delineates the current research frontiers and hotspots, serving as a valuable guide for scholars.

6.
BMC Infect Dis ; 24(1): 199, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38350843

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) is an evolving global pandemic, and nanobodies, as well as other single-domain antibodies (sdAbs), have been recognized as a potential diagnostic and therapeutic tool for infectious diseases. High-throughput screening techniques such as phage display have been developed as an alternative to in vivo immunization for the discovery of antibody-like target-specific binders. METHODS: We designed and constructed a highly diverse synthetic phage library sdAb-U (single-domain Antibody - Universal library ) based on a human framework. The SARS-CoV-2 receptor-binding domain (RBD) was expressed and purified. The universal library sdAb-U was panned against the RBD protein target for two rounds, followed by monoclonal phage ELISA (enzyme-linked immunosorbent assay) to identify RBD-specific binders (the first stage). High-affinity binders were sequenced and the obtained CDR1 and CDR2 sequences were combined with fully randomized CDR3 to construct a targeted (focused) phage library sdAb-RBD, for subsequent second-stage phage panning (also two rounds) and screening. Then, sequences with high single-to-background ratios in phage ELISA were selected for expression. The binding affinities of sdAbs to RBD were measured by an ELISA-based method. In addition, we conducted competition ELISA (using ACE2 ectodomain S19-D615) and SARS-CoV-2 pseudovirus neutralization assays for the high-affinity RBD-binding sdAb39. RESULTS: Significant enrichments were observed in both the first-stage (universal library) and the second-stage (focused library) phage panning. Five RBD-specific binders were identified in the first stage with high ELISA signal-to-background ratios. In the second stage, we observed a much higher possibility of finding RBD-specific clones in phage ELISA. Among 45 selected RBD-positive sequences, we found eight sdAbs can be well expressed, and five of them show high-affinity to RBD (EC50 < 100nM). We finally found that sdAb39 (EC50 ~ 4nM) can compete with ACE2 for binding to RBD. CONCLUSION: Overall, this two-stage strategy of synthetic phage display libraries enables rapid selection of SARS-CoV-2 RBD sdAb with potential therapeutic activity, and this two-stage strategy can potentially be used for rapid discovery of sdAbs against other targets.


Assuntos
Bacteriófagos , COVID-19 , Anticorpos de Domínio Único , Humanos , SARS-CoV-2/genética , Anticorpos de Domínio Único/genética , Anticorpos de Domínio Único/química , Enzima de Conversão de Angiotensina 2 , COVID-19/diagnóstico , Anticorpos Antivirais , Anticorpos Neutralizantes
7.
J Dent Sci ; 19(1): 614-619, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38303894

RESUMO

Background/purpose: 4-Nitroquinoline 1-oxide (4NQO)-induced tongue carcinoma and 7,12-dimethlybenz(a)anthracene (DMBA)-induced cheek pouch carcinoma are the most common and classical chemical carcinogen-induced animal models of oral carcinogenesis. The purpose of this study was to provide the research trends and characteristics of 4NQO- and DMBA-induced experimental oral carcinogenesis. Materials and methods: The papers on both 4NQO- and DMBA-induced experimental oral carcinogenesis were published since 1962. All the eligible papers were retrieved on 12 May 2023 from the Scopus database. Results: There were 506 and 349 papers on 4NQO- and DMBA-induced experimental oral carcinogenesis with 10,152 and 6306 citations, respectively. The common distinctive keywords such as rat, tongue neoplasms, drinking water, tumor microenvironment, and cyclooxygenase (COX)-2 were identified in the papers on 4NQO; and the common keywords such as hamster, cheek pouch, lipid peroxidation, glutathione, antioxidants, and topical drug administration were identified in the papers on DMBA. Importantly, 105 and 65 potential chemopreventive agents were identified from the papers on 4NQO and DMBA, respectively. Furthermore, 15 promising agents such as COX-2 inhibitor, curcumin, garlic were researched concurrently in both the two animal models. Conclusion: This study for the first time reports the scientometric characteristics of 4NQO- and DMBA-induced experimental oral carcinogenesis. Importantly, we identify a valuable profile for oral cancer chemopreventive agents, which will aid researchers and investigators in studying oral cancer chemoprevention.

8.
Org Lett ; 25(48): 8661-8665, 2023 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-38009639

RESUMO

Through systematic optimization of halopyridinium compounds, we established a peptide coupling protocol utilizing 4-iodine N-methylpyridinium (4IMP) for solid-phase peptide synthesis (SPPS). The 4IMP coupling reagent is easily prepared, bench stable, and cost-effective. Employing 4IMP in the SPPS process has showcased remarkable chemoselectivity and efficiency, effectively eliminating racemization and epimerization. This achievement has been substantiated through the successful synthesis of a range of peptides via the direct utilization of commercially available amino acid substrates for SPPS.


Assuntos
Peptídeos , Compostos de Piridínio , Peptídeos/química , Aminoácidos/química , Técnicas de Síntese em Fase Sólida/métodos
9.
Trends Mol Med ; 29(11): 951-967, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37704494

RESUMO

The liver can succumb to oxidant damage during the development of chronic liver diseases. Despite their physiological relevance to hepatic homeostasis, excessive reactive oxygen/nitrogen species (ROS/RNS) production under pathological conditions is detrimental to all liver constituents. Chronic oxidative stress coupled to unresolved inflammation sets in motion the activation of profibrogenic hepatic stellate cells (HSCs) and later pathogenesis of liver fibrosis, cirrhosis, and liver cancer. The liver antioxidant and repair systems, along with autophagic and ferroptotic machineries, are implicated in the onset and trajectory of disease development. In this review, we discuss the ROS/RNS-related mechanisms underlying liver fibrosis of distinct etiologies and highlight preclinical and clinical trials of antifibrotic therapies premised on remediating oxidative/nitrosative stress in hepatocytes or targeting HSC activation.

10.
Sci Rep ; 13(1): 15839, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37739947

RESUMO

For high-level automated vehicles, the human being acts as the passenger instead of the driver and does not need to operate vehicles, it makes the brain-computer interface system of high-level automated vehicles depend on the brain state of passengers rather than that of drivers. Particularly when confronting challenging driving situations, how to implement the mental states of passengers into safe driving is a vital choice in the future. Quantifying the cognition of the driving risk of the passenger is a basic step in achieving this goal. In this paper, the passengers' mental activities in low-risk episode and high-risk episode were compared, the influences on passengers' mental activities caused by driving scenario risk was first explored via fNIRS. The results showed that the mental activities of passengers caused by driving scenario risk in the Brodmann area 10 are very active, which was verified by examining the real-driving data collected in corresponding challenging experiments, and there is a positive correlation between the cerebral oxygen and the driving risk field. This initial finding provides a possible solution to design a human-centred intelligent system to promise safe driving for high-level automated vehicles using passengers' driving risk cognition.


Assuntos
Cognição , Córtex Pré-Frontal , Humanos , Encéfalo , Análise Espectral , Veículos Autônomos
11.
Heliyon ; 9(8): e18764, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37576285

RESUMO

Progression to a severe condition remains a major risk factor for the COVID-19 mortality. Robust models that predict the onset of severe COVID-19 are urgently required to support sensitive decisions regarding patients and their treatments. In this study, we developed a multivariate survival model based on early-stage CT images and other physiological indicators and biomarkers using artificial-intelligence analysis to assess the risk of severe COVID-19 onset. We retrospectively enrolled 338 adult patients admitted to a hospital in China (severity rate, 31.9%; mortality rate, 0.9%). The physiological and pathological characteristics of the patients with severe and non-severe outcomes were compared. Age, body mass index, fever symptoms upon admission, coexisting hypertension, and diabetes were the risk factors for severe progression. Compared with the non-severe group, the severe group demonstrated abnormalities in biomarkers indicating organ function, inflammatory responses, blood oxygen, and coagulation function at an early stage. In addition, by integrating the intuitive CT images, the multivariable survival model showed significantly improved performance in predicting the onset of severe disease (mean time-dependent area under the curve = 0.880). Multivariate survival models based on early-stage CT images and other physiological indicators and biomarkers have shown high potential for predicting the onset of severe COVID-19.

13.
Eur Phys J C Part Fields ; 83(7): 599, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37448709

RESUMO

This Letter proposes a new signature for confining dark sectors at the Large Hadron Collider. Under the assumption of a QCD-like hidden sector, hadronic jets containing stable dark bound states could manifest in proton-proton collisions. We present a simplified model with a Z' boson yielding the production of jets made up of dark bound states and subsequently leading to the decays of those that are unstable to τ leptons and Standard Model quarks. The resulting signature is characterised by non-isolated τ lepton pairs inside semi-visible jets. We estimate the constraints on our model from existing CMS and ATLAS analyses. We propose a set of variables that leverage the leptonic content of the jet and exploit them in a supervised jet tagger to enhance the signal-to-background separation. Furthermore, we discuss the performance and limitations of current triggers for accessing sub-TeV Z' masses, as well as possible strategies that can be adopted by experiments to access such low mass regions. We estimate that with the currently available triggers, a high mass search can claim a 5σ discovery (exclusion) of the Z' boson with a mass up to 4.5 TeV (5.5 TeV) with the full Run 2 data of the LHC when the fraction of unstable dark hadrons decaying to τ lepton pairs is around 50%, and with a coupling of the Z' to right-handed up-type quarks of 0.25. Furthermore, we show that, with new trigger strategies for Run 3, it may be possible to access Z' masses down to 700 GeV, for which the event topology is still composed of two resolved semi-visible jets.

14.
Biochem Biophys Rep ; 35: 101508, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37448811

RESUMO

Peptides can be used as effective molecular tool for covalent modification of proteins and play important roles in ligand directed covalent modification. Tyr-selective protein modifications exert a profound impact on protein functionality. Here, we developed a general strategy that involves nucleophilic addition of alkyne for tyrosine modification. The terminal alkyne of propargyl sulfonium is motivated by the sulfonium center to react with phenolic hydroxyl. This approach provides a straightforward method for tyrosine modification due to its high yield in aqueous solution at physiological temperature. In addition, cyclic peptides could be obtained via adjusting pH to 8.0 from peptides consisting of tyrosine and methionine modified by propargyl bromide, and the resulting cyclic peptides are proved to have better stability, excellent 2-mercaptopyridine resistance and improved cellular uptakes. Furthermore, molecules made from the propargylated sulfonium have the potential to be used as warheads against tyrosine containing biomolecules. Collectively, we develop a direct and uncomplicated technique for modifying tyrosine residues, the strategy concerned can be widely utilized to construct stable peptides and biomolecules imaging.

15.
Gut Microbes ; 15(1): 2221485, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37345844

RESUMO

Current evidence indicates that the next-generation probiotic Akkermansia muciniphila (A. muciniphila) has therapeutic potential for nonalcoholic fatty liver disease (NAFLD), especially its inflammatory stage known as nonalcoholic steatohepatitis (NASH). However, the mechanisms of A. muciniphila in NASH prevention remain unknown. Here, A. muciniphila supplementation prevented hepatic inflammation in high-fat diet-induced NASH mice, characterized by reduced hepatic proinflammatory macrophages (M1) and γδT and γδT17 cells. Consistently, hepatic M1 and γδT cells were enriched in biopsy-proven NASH patients and high-fat/high-carbohydrate diet-induced NASH mice. Antibiotics reduced hepatic M1, γδT and γδT17 cells in NASH mice. Furthermore, A. muciniphila inhibited intestinal barrier disruption and accordingly downregulated hepatic Toll-like receptor 2 (TLR2) expression in NASH mice. The activation of TLR2 by lipoteichoic acid enriched hepatic γδT17 cells (not M1) in normal diet-fed mice and neutralized the γδT cell-lowering and liver inflammation-protecting effects of A. muciniphila in NASH mice. Additionally, activated γδT cells could promote macrophage polarization via IL-17. Our study first supported that A. muciniphila prevented NASH by modulating TLR2-activated γδT17 cells and further macrophage polarization, facilitating clinical therapeutic applications.


Assuntos
Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Receptor 2 Toll-Like/genética , Verrucomicrobia , Inflamação , Macrófagos
16.
Artigo em Inglês | MEDLINE | ID: mdl-37276092

RESUMO

Multiagent deep reinforcement learning (DRL) makes optimal decisions dependent on system states observed by agents, but any uncertainty on the observations may mislead agents to take wrong actions. The mean-field actor-critic (MFAC) reinforcement learning is well-known in the multiagent field since it can effectively handle a scalability problem. However, it is sensitive to state perturbations that can significantly degrade the team rewards. This work proposes a Robust MFAC (RoMFAC) reinforcement learning that has two innovations: 1) a new objective function of training actors, composed of a policy gradient function that is related to the expected cumulative discount reward on sampled clean states and an action loss function that represents the difference between actions taken on clean and adversarial states and 2) a repetitive regularization of the action loss, ensuring the trained actors to obtain excellent performance. Furthermore, this work proposes a game model named a state-adversarial stochastic game (SASG). Despite the Nash equilibrium of SASG may not exist, adversarial perturbations to states in the RoMFAC are proven to be defensible based on SASG. Experimental results show that RoMFAC is robust against adversarial perturbations while maintaining its competitive performance in environments without perturbations.

17.
Toxics ; 11(5)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37235262

RESUMO

As a typical environmental endocrine disrupting chemical (EDC), di-(2-ethylhexyl) phthalate (DEHP) is thought to be related to reproductive disorders, especially in males. Growing evidence suggests that various EDCs may result in an impaired telomere structure and function, which is associated with male infertility. However, the adverse effect of DEHP on telomeres in male reproductive cells has rarely been studied, and the related mechanisms remain unclear. In this study, we tested the effects of mono-(2-ethylhexyl) phthalate (MEHP), the primary metabolite of DEHP, on telomere dysfunction in mouse spermatogonia-derived cells (GC-1) and the potential role of TERT and c-Myc in MEHP-induced spermatogenic cell damage. Results showed that MEHP induced cell viability inhibition, G0/G1 phase cell cycle arrest, and apoptosis in GC-1 cells in a dose-dependent manner. Shortened telomeres, reduced telomerase activity, and decreased expression of TERT, c-Myc, and upstream transcription factors of c-Myc were also observed in the MEHP-treated cells. In conclusion, it can be concluded that TERT-mediated telomere dysfunction may contribute to MEHP-induced G0/G1 phase cell cycle arrest and apoptosis in GC-1 cells through the impairment of c-Myc and its upstream transcription factors.

18.
Chem Sci ; 14(3): 604-612, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36741507

RESUMO

Visible-light-mediated methods were heavily studied as a useful tool for cysteine-selective bio-conjugation; however, many current methods suffer from bio-incompatible reaction conditions and slow kinetics. To address these challenges, herein, we report a transition metal-free thiol-sulfoxonium ylide photo-click reaction that enables bioconjugation under bio-compatible conditions. The reaction is highly cysteine-selective and generally finished within minutes with naturally occurring riboflavin derivatives as organic photocatalysts. The catalysts and substrates are readily accessible and bench stable and have satisfactory water solubility. As a proof-of-concept study, the reaction was smoothly applied in chemo-proteomic analysis, which provides efficient tools to explore the druggable content of the human proteome.

19.
Heliyon ; 9(1): e12365, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36699260

RESUMO

This study is a first report on the identification of multidrug-resistant (MDR) Acinetobacter bereziniae among non-baumannii acinetobacters that had previously escaped automated laboratory detection, and characterize their clinical courses of infection at two tertiary-care hospitals in Shenzhen city, China (2015-2017). Herein, definitive identification by PCR was performed with universal and species-specific primers targeting 16S rDNA and rpoB genes, respectively, followed by Sanger sequencing and blast analysis. Antimicrobial susceptibility of A. bereziniae isolates was assessed accordingly. Three of the five identified A. bereziniae isolates exhibited carbapenem-resistance and were subjected to a multiplex PCR assay to detect drug-resistance genes. Sequences of the rpoB amplicon were aligned with curated sequences from global databases for phylogenetic analysis on evolutionary relations. Five clinical isolates of A. bereziniae were thereby re-identified, whose infections were primarily nosocomial. Automated identification and susceptibility testing systems (Phoenix-100 and VITEK 2) proved insufficient for discriminating A. bereziniae from other acinetobacters such as Acinetobacter baumannii and Acinetobacter guillouiae. Among these isolates, three exhibited carbapenem-resistant phenotypes indistinguishable from that of carbapenem-resistant A. baumannii. The carbapenem-resistant A. bereziniae isolates were subsequently confirmed to carry a bla NDM-1 (New Delhi metallo-ß-lactamase-1) gene downstream of ISAba125. Phylogenetic analysis revealed that A. bereziniae isolates evolved slowly but independently in local habitats. A. bereziniae isolates are difficult to distinguish by traditional automated detection systems. PCR-based identification via amplification and sequencing of selected house-keeping genes provides sufficient resolution for discriminating the isolates.

20.
Environ Pollut ; 319: 120943, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36584854

RESUMO

Numerous evidence showed that the occurrence and development of lung cancer is closely related to environmental pollution. Therefore, new environmental response predictive markers are urgently needed for early diagnosis and screening of lung cancer. Interferon-induced protein 44-like (IFI44L) has been shown to be related in a variety of tumors, but its function and mechanism during lung carcinogenesis still have remained largely unknown. In this study, gene expression and methylation status were analyzed through online tools and malignant transformation models. Differentially expressed cell models and xenograft tumor models were established and used to clarify the gene function. RT-qPCR, western blotting, immunohistochemistry, and co-immunoprecipitation (Co-IP) were used to explore the mechanism. Results showed that IFI44L was dramatically downexpressed during lung carcinogenesis, and its low expression may be attributed to DNA methylation. Overexpression of IFI44L obviously inhibited cell growth and promoted apoptosis. After knockdown of IFI44L expression, the proliferation ability was remarkably increased and the apoptosis was significantly reduced. Functional enrichment showed that IFI44L was involved in apoptosis and JAK/STAT1 signaling pathway, and was highly correlated with downstream molecules. After overexpression of IFI44L, the expression of P-STAT1 and downstream molecules XAF1, OAS1, OAS2 and OAS3 were significantly increased. After knockdown of STAT1 expression, the pro-apoptotic effect of IFI44L was reduced. Co-IP results showed that IFI44L had protein interaction with STAT1. Results proved that IFI44L promoted STAT1 phosphorylation and activated the JAK/STAT1 signaling pathway by directly binding to STAT1 protein, thereby leading to cell apoptosis. Our study revealed that IFI44L promotes cell apoptosis and exerts tumor suppressors by activating the JAK/STAT1 signaling pathway. It further suggests that IFI44L has clinical therapeutic potential and may be a promising biomarker during lung carcinogenesis.


Assuntos
Neoplasias Pulmonares , Humanos , Apoptose , Carcinogênese/genética , Linhagem Celular Tumoral , Epigênese Genética , Pulmão/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo
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