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1.
Mol Ther ; 31(8): 2489-2506, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37087570

RESUMO

Growing evidence has proved that RNA editing enzyme ADAR1, responsible for detecting endogenous RNA species, was significantly associated with poor response or resistance to immune checkpoint blockade (ICB) therapy. Here, a genetically engineered nanovesicle (siAdar1-LNP@mPD1) was developed as an RNA interference nano-tool to overcome tumor resistance to ICB therapies. Small interfering RNA against ADAR1 (siAdar1) was packaged into a lipid nanoparticle (LNP), which was further coated with plasma membrane extracted from the genetically engineered cells overexpressing PD1. siAdar1-LNP@mPD1 could block the PD1/PDL1 immune inhibitory axis by presenting the PD1 protein on the coating membranes. Furthermore, siAdar1 could be effectively delivered into cancer cells by the designed nanovesicle to silence ADAR1 expression, resulting in an increased type I/II interferon (IFN-ß/γ) production and making the cancer cells more sensitive to secreted effector cytokines such as IFN-γ with significant cell growth arrest. These integrated functions confer siAdar1-LNP@mPD1 with robust and comprehensive antitumor immunity, as evidenced by significant tumor growth regression, abscopal tumor prevention, and effective suppression of lung metastasis, through a global remodeling of the tumor immune microenvironment. Overall, we provided a promising translatable strategy to simultaneously silence ADAR1 and block PDL1 immune checkpoint to boost robust antitumor immunity.


Assuntos
Citocinas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/terapia , Interferon gama , Proliferação de Células , Microambiente Tumoral/genética
2.
J Orthop Sci ; 29(2): 621-626, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36858837

RESUMO

BACKGROUND: The aim of this study was to explore the clinical efficacy of ankle arthrodesis with different internal fixation methods in the treatment of post-traumatic osteoarthritis. METHODS: We collected 85 patients with post-traumatic osteoarthritis who underwent different ankle arthrodesis between December 2015 and December 2020. The operation performance, complication rate, hindfoot alignment, talus tilt angle, visual analogue scale (VAS), and American Orthopedic Foot and Ankle Society (AOFAS) score were preoperatively and postoperatively evaluated. RESULTS: In an anterior approach, the locking plate-fixation exhibited a similarity in operation time, incision length, postoperative drainage, bone fusion, hindfoot alignment, and talus tilt angle with fibula support compression screw-fixation, but it was better in increasing postoperative AOFAS. The locking plate-fixation in the anterior approach had lower operation time, incision length, and postoperative drainage than that in the lateral approach. In addition, the lateral locking plate combined with posterolateral compression screw fixation (LLPPCSF) presented shorter bone fusion time, higher AOFAS score, and lower complication rate than either plate- or screw-fixation alone. CONCLUSION: Lateral locking plate fixation was better than fibula support compression screw fixation in relieving postoperative pain. Anterior locking plate fixation was more time-saving and less invasiveness than lateral locking plate fixation, but its application was limited in low degree of ankle deformation. LLPPCSF was the most effective in improving bone fusion and postoperative pain, considering an optimal option for the treatment of post-traumatic osteoarthritis.


Assuntos
Tornozelo , Osteoartrite , Humanos , Fixação Interna de Fraturas/métodos , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/cirurgia , Resultado do Tratamento , Placas Ósseas , Artrodese/métodos , Osteoartrite/diagnóstico por imagem , Osteoartrite/etiologia , Osteoartrite/cirurgia , Dor Pós-Operatória , Estudos Retrospectivos
3.
Entropy (Basel) ; 26(2)2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38392414

RESUMO

Public transportation infrastructure is a typical, complex, coupled network that is usually composed of connected bus lines and subway networks. This study proposes an entropy-based node importance identification method for this type of coupled network that is helpful for the integrated planning of urban public transport and traffic flows, as well as enhancing network information dissemination and maintaining network resilience. The proposed method develops a systematic entropy-based metric based on five centrality metrics, namely the degree centrality (DC), betweenness centrality (BC), closeness centrality (CC), eigenvector centrality (EC), and clustering coefficient (CCO). It then identifies the most important nodes in the coupled networks by considering the information entropy of the nodes and their neighboring ones. To evaluate the performance of the proposed method, a bus-subway coupled network in Chengdu, containing 10,652 nodes and 15,476 edges, is employed as a case study. Four network resilience assessment metrics, namely the maximum connectivity coefficient (MCC), network efficiency (NE), susceptibility (S), and natural connectivity (NC), were used to conduct group experiments. The experimental results demonstrate the following: (1) the multi-functional fitting analysis improves the analytical accuracy by 30% as compared to fitting with power law functions only; (2) for both CC and CCO, the improved metric's performance in important node identification is greatly improved, and it demonstrates good network resilience.

4.
J Sep Sci ; 45(6): 1222-1239, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35080126

RESUMO

Celastrol has attracted great attention owing to its anti-arthritis, antioxidant, and anticancer activities. Nevertheless, its metabolism in vivo (rats) and in vitro (rat liver microsomes and intestinal flora) has not been comprehensively characterized. In this study, ultra-high-performance liquid chromatography coupled with hybrid triple quadrupole time-of-flight mass spectrometry was used as a rapid and sensitive approach for studying the metabolism of celastrol in vivo and in vitro. A total of 43 metabolites were identified and characterized. These include 26 metabolites in vivo, and 28 metabolites in vitro (nine metabolites in rat liver microsomes and 24 metabolites in rat intestinal flora). Additionally, the celastrol-biotransformation capacity of the intestinal tract was confirmed to exceed that of the liver. Furthermore, the metabolic profile of celastrol is summarised. The information obtained from this study may provide a basis for understanding the pharmacological mechanisms of celastrol and will be beneficial for clinical applications.


Assuntos
Microssomos Hepáticos , Animais , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Microssomos Hepáticos/metabolismo , Triterpenos Pentacíclicos/metabolismo , Ratos , Ratos Sprague-Dawley
5.
Rare Metals ; 41(2): 559-569, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34177195

RESUMO

Copper (Cu)-bearing stainless steel has testified its effectiveness to reduce the risk of bacterial infections. However, its antibacterial mechanism is still controversial. Therefore, three 430 ferritic stainless steels with different Cu contents are selected to conduct deeper research by the way of bacterial inactivation from two aspects of material and biology. Hereinto, electrochemical and antibacterial results show that the increase in Cu content simultaneously improves the corrosion resistance and antibacterial property of 430 stainless steel. In addition, it is found that Escherichia coli (E. coli) on the surface 430 Cu-bearing stainless steel by the dry method of inoculation possesses a rapid inactivation ability. X-ray photoelectron spectroscopy (XPS) aids with ion chelation experiments prove that Cu (I) plays a more crucial role in the contact-killing efficiency than Cu (II), resulting from more production of reactive oxygen species (ROS).

6.
Cancer Sci ; 112(9): 3555-3568, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34255396

RESUMO

The long reads of Nanopore sequencing permit accurate transcript assembly and ease in discovering novel transcripts with potentially important functions in cancers. The wide adoption of Nanopore sequencing for transcript quantification, however, is largely limited by high costs. To address this issue, we developed a bioinformatics software, NovelQuant, that can specifically quantify long-read-assembled novel transcripts with short-read sequencing data. Nanopore Direct RNA Sequencing was carried out on three hepatocellular carcinoma (HCC) patients' tumor, matched portal vein tumor thrombus, and peritumor to reconstruct the HCC transcriptome. Then, based on the reconstructed transcriptome, NovelQuant was applied on Illumina RNA sequencing data of 59 HCC patients' tumor and paired peritumor to quantify novel transcripts. Our further analysis revealed 361 novel transcripts dysregulated in HCC and that 101 of them were significantly associated with prognosis. There were 19 novel prognostic transcripts predicted to be long noncoding RNAs (lncRNAs), and some of them had regulatory targets that were reported to be associated with HCC. Additionally, 42 novel prognostic transcripts were predicted to be protein-coding mRNAs, and many of them could be involved in xenobiotic metabolism. Moreover, the tumor-suppressive roles of two representative novel prognostic transcripts, CDO1-novel (lncRNA) and CYP2A6-novel (protein-coding mRNA), were further functionally validated during HCC progression. Overall, the current study shows a possibility of combining long- and short-read sequencing to explore functionally important novel transcripts in HCC with accuracy and cost-efficiency, which expands the pool of molecular biomarkers that could enhance our understanding of the molecular mechanisms of HCC.


Assuntos
Carcinoma Hepatocelular/genética , Confiabilidade dos Dados , Neoplasias Hepáticas/genética , Sequenciamento por Nanoporos/métodos , Análise de Sequência de RNA/métodos , Transcriptoma , Idoso , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Biologia Computacional/métodos , Progressão da Doença , Feminino , Perfilação da Expressão Gênica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , RNA Longo não Codificante/genética , RNA Mensageiro/genética , Software
7.
Angew Chem Int Ed Engl ; 60(42): 22646-22651, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34291539

RESUMO

N6 -methyladenosine (m6 A) modification-the most prevalent mammalian RNA internal modification-plays key regulatory roles in mRNA metabolism. Current approaches for m6 A modified RNA analysis limit at bulk-population level, resulting in a loss of spatiotemporal and cell-to-cell variability information. Here we proposed a m6 A-specific in situ hybridization mediated proximity ligation assay (m6 AISH-PLA) for cellular imaging of m6 A RNA, allowing to identify m6 A modification at specific location in RNAs and image m6 A RNA with single-cell and single-molecule resolution. Using m6 AISH-PLA, we investigated the m6 A level and subcellular location of HSP70 RNA103-m6 A in response to heat shock stress, and found an increased m6 A modified ratio and an increased distribution ratio in cytoplasm under heat shock. m6 AISH-PLA can serve in the study of m6 A RNA in single cells for deciphering epitranscriptomic mechanisms and assisting clinical diagnosis.


Assuntos
Adenosina/análogos & derivados , Hibridização In Situ/métodos , RNA/metabolismo , Adenosina/química , Linhagem Celular , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , RNA/química , RNA Mensageiro/metabolismo , Análise de Célula Única
8.
Molecules ; 24(14)2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31340434

RESUMO

Eupatorin is the major bioactive component of Java tea (Orthosiphon stamineus), exhibiting strong anticancer and anti-inflammatory activities. However, no research on the metabolism of eupatorin has been reported to date. In the present study, ultra-high-performance liquid chromatography coupled with hybrid triple quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) combined with an efficient online data acquisition and a multiple data processing method were developed for metabolite identification in vivo (rat plasma, bile, urine and feces) and in vitro (rat liver microsomes and intestinal flora). A total of 51 metabolites in vivo, 60 metabolites in vitro were structurally characterized. The loss of CH2, CH2O, O, CO, oxidation, methylation, glucuronidation, sulfate conjugation, N-acetylation, hydrogenation, ketone formation, glycine conjugation, glutamine conjugation and glucose conjugation were the main metabolic pathways of eupatorin. This was the first identification of metabolites of eupatorin in vivo and in vitro and it will provide reference and valuable evidence for further development of new pharmaceuticals and pharmacological mechanisms.


Assuntos
Flavonoides/farmacocinética , Glicoconjugados/isolamento & purificação , Microssomos Hepáticos/metabolismo , Orthosiphon/química , Acetilação , Animais , Bile/química , Biotransformação , Fezes/química , Flavonoides/sangue , Flavonoides/urina , Microbioma Gastrointestinal/fisiologia , Glicoconjugados/metabolismo , Hidrogenação , Masculino , Metilação , Oxirredução , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
9.
Molecules ; 24(19)2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31554336

RESUMO

Although farrerol, a characteristically bioactive constituent of Rhododendron dauricum L., exhibits extensive biological and pharmacological activities (e.g., anti-oxidant, anti-immunogenic, and anti-angiogenic) as well as a high drug development potential, its metabolism remains underexplored. Herein, we employed ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry coupled with multiple data post-processing techniques to rapidly identify farrerol metabolites produced in vivo (in rat blood, bile, urine and feces) and in vitro (in rat liver microsomes). As a result, 42 in vivo metabolites and 15 in vitro metabolites were detected, and farrerol shown to mainly undergo oxidation, reduction, (de)methylation, glucose conjugation, glucuronide conjugation, sulfate conjugation, N-acetylation and N-acetylcysteine conjugation. Thus, this work elaborates the metabolic pathways of farrerol and reveals the potential pharmacodynamics forms of farrerol.


Assuntos
Cromatografia Líquida de Alta Pressão , Cromonas/química , Cromonas/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem , Desintoxicação Metabólica Fase I , Desintoxicação Metabólica Fase II , Estrutura Molecular , Oxirredução
10.
J Am Chem Soc ; 140(36): 11293-11301, 2018 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-30125486

RESUMO

The accumulation of mitochondrial DNA (mtDNA) mutations in cells is strongly related to aging-associated diseases. Imaging of single-nucleotide variation (SNV) in mtDNA is crucial for understanding the heteroplasmy of mtDNAs that harbor pathogenic changes. Herein, we designed a CRISPR/Cas9-mediated proximity ligation assay (CasPLA) for direct visualization of the ND4 and ND5 genes in the mtDNAs of single cells. Taking advantage of the high specificity of CRISPR/Cas9, CasPLA can be used to image SNV in the ND4 gene at single-molecule resolution. Using CasPLA, we observed a mtDNA-transferring process between different cells through a tunneling nanotube, which may account for the spreading of mtDNA heteroplasmy. Moreover, we demonstrated that CasPLA strategy can be applied for imaging of single copy genomic loci ( KRAS gene) in the nuclear genome. Our results establish CasPLA as a tool to study SNV in situ in single cells for basic research and genetic diagnosis.


Assuntos
Sistemas CRISPR-Cas/genética , DNA Mitocondrial/genética , Variação Genética/genética , Polimorfismo de Nucleotídeo Único/genética , Humanos , Células MCF-7 , Mutação , Células Tumorais Cultivadas
11.
Anal Chem ; 90(16): 10001-10008, 2018 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-30016869

RESUMO

MicroRNAs (miRNAs) play key roles in regulating gene expression and cell functions, which are recognized as potential biomarkers for many human diseases. Sensitive, specific, and reliable detection of miRNA is highly demanded for clinical diagnosis and therapy. Herein, we describe a label-free and low-background fluorescent assay, termed amplified tandem Spinach-based aptamer transcription assay (AmptSpi assay) for highly sensitive miRNA detection by polymeric rolling circle amplicon mediated multiple transcription. Target miRNA is recognized by padlock probe to form polymeric rolling circle amplicon. Then the following transcription process rapidly produces large amounts of repeats of RNA Spinach aptamers, lightened up by the addition of fluorescent dye DFHBI for miRNA quantitative analysis, achieving label-free and nearly zero-background. Besides, the assay could also confer high selectivity to distinguish miRNA among the miRNA family members with 1- or 2-nucleotide (nt) difference. This method was capable of completing detection in human serum sample or cell extracts in hours, indicating great potential in the early diagnosis of diseases.


Assuntos
Aptâmeros de Nucleotídeos/genética , MicroRNAs/sangue , Técnicas de Amplificação de Ácido Nucleico/métodos , Compostos de Benzil/química , Fluorescência , Humanos , Imidazolinas/química , Limite de Detecção , MicroRNAs/genética , Hibridização de Ácido Nucleico , Transcrição Gênica/genética
12.
Xenobiotica ; 48(7): 676-683, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28756727

RESUMO

1. For the first time, a systemic in vivo investigation was employed to evaluate the potential effects of m-nisoldipine on activities of rat cytochrome P450 enzymes (CYP1A2, CYP2C11, CYP2D1 and CYP3A1) by both cocktail probe drugs and the quantitative real-time reverse-transcription polymerase chain reaction (RT-qPCR). 2. m-Nisoldipine-treated and blank control groups were respectively administered m-nisoldipine at the dosage of 2.5, 5 and 12.5 mg/kg and CMC-Na solution for 15 days consecutively, then they were given the probe drugs of caffeine, diclofenac, dextromethorphan and midazolam (all probes were 5 mg/kg) by p.o. The blood samples were collected at different times for liquid chromatography coupled with mass spectrometry (LC-MS) analysis. The corresponding pharmacokinetic parameters were applied to evaluate the effects of m-nisoldipine on the four CYP isoforms in vivo. In addition, RT-qPCR was performed to determine the effects of m-nisoldipine on the mRNA expression of CYPs in rat liver. Results indicated that high dose and middle dose of m-nisoldipine showed significant effects on all four CYPs and CYP2C11, respectively. Moreover, for CYP2D1 and CYP1A2, there were no significant effects found at either low or middle dose of m-nisoldipine. 3. This study could provide not only experimental evidence for potential clinical application of m-nisoldipine but also a practical strategy for assessing CYP-mediated drug-drug interactions.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Nisoldipino/farmacologia , Animais , Hidrocarboneto de Aril Hidroxilases , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP3A/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Família 2 do Citocromo P450/metabolismo , Masculino , Midazolam/farmacocinética , Sondas Moleculares/química , Nisoldipino/sangue , Nisoldipino/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Esteroide 16-alfa-Hidroxilase , Fatores de Tempo
13.
Biomed Chromatogr ; 32(2)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28702943

RESUMO

Farfarae Flos, the dried flower buds of Tussilago farfara L., is usually used to treat coughs, bronchitic and asthmatic conditions as an important traditional Chinese medicine. Tussilagone and methl butyric acid tussilagin ester are seen as representatives of two kinds of active substances. In addition, the pyrrolizidine alkaloids, mainly senkirkine and senecionine, present in the herb can be hepatoxic. In this study, a rapid and sensitive ultra-high-performance liquid chromatography coupled with hybrid triple quadrupole time-of-flight mass spectrometry method was successfully applied to identify the metabolites of tussilagone, methl butyric acid tussilagin ester, senkirkine and senecionine. A total of 35, 37, 18 and nine metabolites of tussilagone, methl butyric acid tussilagin ester, senkirkine and senecionine in rats were tentatively identified. Hydrolysis, oxidation, reduction and demethylation were the major metabolic reactions for tussilagone and methl butyric acid tussilagin ester. The main biotransformation routes of senkirkine and senecionine were identified as demethylation, N-methylation, oxidation and reduction. This study is the first reported analysis and characterization of the metabolites and the proposed metabolic pathways might provide further understanding of the metabolic fate of the chemical constituents after oral administration of Farfarae Flos extract in vivo.


Assuntos
Asteraceae/química , Medicamentos de Ervas Chinesas/química , Alcaloides de Pirrolizidina/análise , Sesquiterpenos/análise , Administração Oral , Animais , Bile/química , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/farmacocinética , Fezes/química , Masculino , Alcaloides de Pirrolizidina/química , Alcaloides de Pirrolizidina/farmacocinética , Ratos , Ratos Sprague-Dawley , Sesquiterpenos/química , Sesquiterpenos/farmacocinética , Espectrometria de Massas em Tandem/métodos
14.
Biomed Chromatogr ; : e4263, 2018 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-29669394

RESUMO

Helicid is an active natural aromatic phenolic glycoside ingredient originating from a well-known traditional Chinese herbal medicine and has the significant effects of sedative hypnosis, anti-inflammatory analgesia and antidepressant. In this study, we analyzed the potential metabolites of Helicid in rats by multiple mass defect filter and dynamic background subtraction in ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS). Moreover, we used a novel data processing method, 'key product ions', to rapidly detect and identify metabolites as an assistant tool. MetabolitePilot™ 2.0 software and PeakView™ 2.2 software were used for analyzing metabolites. Twenty metabolites of Helicid (including 15 phase I metabolites and five phase II metabolites) were detected by comparison with the blank samples. The biotransformation route of Helicid was identified as demethylation, oxidation, dehydroxylation, hydrogenation, decarbonylation, glucuronide conjugation and methylation. This is the first study simultaneously detecting and identifying Helicid metabolism in rats employing UHPLC-Q-TOF-MS technology. This experiment not only proposed a method for rapidly detecting and identifying metabolites, but also provided useful information for further study of the pharmacology and mechanism of Helicid in vivo. Furthermore, it provided an effective method for the analysis of other aromatic phenolic glycosides metabolic components in vivo.

15.
Biomed Chromatogr ; 30(9): 1498-505, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26910368

RESUMO

Prim-O-glucosylcimifugin (PGCN) and cimifugin (CN) are major constituents of Radix Saposhnikoviae that have antipyretic, analgesic and anti-inflammatory pharmacological activities. However, there were few reports with respect to the metabolism of PGCN and CN in vitro. In this paper, we describe a strategy using ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) for fast analysis of the metabolic profile of PGCN and CN in human liver microsomes. In total, five phase I metabolites of PGCN, seven phase I metabolites and two phase II metabolites of CN were identified in the incubation of human liver microsomes. The results revealed that the main phase I metabolic pathways of PGCN were hydroxylation and hydrolysis reactions. The phase I metabolic pathways of CN were found to be hydroxylation, demethylation and dehydrogenation. Meanwhile, the results indicated that O-glucuronidation was the major metabolic pathway of CN in phase II metabolism. The specific UDP-glucuronosyltransferase (UGT) enzymes responsible for CN glucuronidation metabolites were identified using recombinant UGT enzymes. The results indicated that UGT1A1, UGT1A9, UGT2B4 and UGT2B7 might play major roles in the glucuronidation of CN. Overall, this study may be useful for the investigation of metabolic mechanism of PGCN and CN, and it can provide reference and evidence for further pharmacodynamic experiments. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Cromatografia Líquida/métodos , Cromonas/metabolismo , Espectrometria de Massas/métodos , Microssomos Hepáticos/metabolismo , Monossacarídeos/metabolismo , Xantenos/metabolismo , Humanos , Padrões de Referência
16.
Biomed Chromatogr ; 29(12): 1893-900, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25994315

RESUMO

m-Nisoldipine, as a novel 1,4-dihydropyridine calcium ion antagonist, was presented as a couple of enantiomers [(-), (+)-m-nisoldipine]. In this report, the in vitro metabolism of m-nisoldipine enantiomers was investigated in rat liver microsomes (RLM) by the combination of two liquid chromatography mass spectrometric techniques for the first time. The metabolites were separated and assayed by ultra-high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry and further identified by comparison of their mass and chromatographic behaviors with reference substances. A total of 18 metabolites of (-)-m-nisoldipine and 16 metabolites of (+)-m-nisoldipine were detected, respectively, which demonstrated that (+)-m-nisoldipine is more metabolically stable than (-)-m-nisoldipine. In addition, the identified metabolic pathways of m-nisoldipine enantiomers were involved in dehydrogenation, oxidation and ester hydrolysis. Afterwards, based on high-performance liquid chromatography coupled to triple quadrupole linear ion trap mass spectrometry, various selective cytochrome P450 (CYP) enzyme inhibitors were employed to evaluate CYP isoforms. The results indicated that the inhibitors of CYP1A1/2, CYP2B1/2, 2D and 2C11 had no obvious inhibitory effects, yet the inhibitor of CYP 3A had a significant inhibitory effect on metabolism of m-nisoldipine enantiomers. This showed that CYP 3A might primarily metabolize m-nisoldipine in RLM.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Microssomos Hepáticos/metabolismo , Nisoldipino/análise , Nisoldipino/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Inibidores das Enzimas do Citocromo P-450/farmacologia , Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Masculino , Nisoldipino/química , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Estereoisomerismo
17.
J Biophotonics ; 17(2): e202300374, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37885324

RESUMO

The immune status of tumor-infiltrating lymphocytes (TILs) is essential for the effectiveness of cancer immunotherapies. However, due to the diversity of immune status in TILs, cellular heterogeneity, and the applicability to the clinic, it is still lacking effective strategies to meet clinical needs. We developed a novel immuno-recognition-induced method based on rolling circle amplification (RCA), namely immunoRCA, to in situ visualize the immune status of TILs in actual clinical samples. This developed immunoRCA method, in which, feature mRNAs were used as the biomarkers for the immune status of TILs, has a low fluorescence background, high sensitivity, and specificity. The immunoRCA was able to efficiently evaluate the immune status of CD8+ T cells regulated by activating or inhibiting factors, track the T cell type and immune status during in vitro expansion, and in situ visualize the number, location, and immune status of TILs in clinical specimens.


Assuntos
Linfócitos T CD8-Positivos , Linfócitos do Interstício Tumoral , Linfócitos do Interstício Tumoral/metabolismo , Biomarcadores/metabolismo
18.
Anal Chim Acta ; 1310: 342702, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811141

RESUMO

BACKGROUND: Currently, millions of people suffer from undiagnosed chronic hepatitis B (CHB) infection each year, which leads to high mortality rates attributed to cirrhosis and hepatocellular carcinoma. Previously reported assays, such as PCR-based assays, have limitations in terms of convenient for CHB screening in high-burden regions and resource-limited settings. Recently, diagnosis based on CRISPR/Cas, which has been considered as a potential method of point-of-care test (POCT) in resource-limited settings, offers a significant advantage in terms of high sensitivity and specificity. Therefore, there is an urgent need for the hepatitis B virus (HBV) detection utilizing CRISPR/Cas system. RESULTS: We have proposed a one-pot of one-step method for CRISPR/Cas12b assisted loop-mediated isothermal amplification (LAMP) to facilitate the quick, sensitive, and precise quantification of HBV DNA. This method is designed for point-of-care testing following genomic extraction or sample heat treatment. We have optimized several critical factors, such as the reaction buffer, AapCas12b-gRNA concentration, reporter and its concentration, reaction temperature, and chemical additives, to significantly enhance the performance of the one-pot assay for HBV. Importantly, it exhibited no cross-reactivity between HBV and blood-borne pathogens. Moreover, the assay is capable of quantifying HBV DNA within 1 h with a limit of detection (LOD) of 25 copies per milliliter. Additionally, when tested on 236 clinical samples, the assay demonstrated a sensitivity of 99.00 % (198/200) and a specificity of 100.00 % (36/36) at the 99 % confidence level compared to real-time quantitative PCR. SIGNIFICANCE: The utilization of convenient and reliable point-of-care diagnostic methods is crucial for reducing the burden of CHB globally. The assay we developed was helpful to improve the ability of HBV diagnosis for practical clinical translation, especially in high-burden regions and resource-limited settings. It has great advantages for rapid screening of CHB as well as evaluation of therapeutic efficacy as a companion diagnostic method.


Assuntos
Sistemas CRISPR-Cas , DNA Viral , Vírus da Hepatite B , Técnicas de Amplificação de Ácido Nucleico , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Sistemas CRISPR-Cas/genética , DNA Viral/genética , DNA Viral/análise , Humanos , Hepatite B Crônica/diagnóstico , Limite de Detecção , Técnicas de Diagnóstico Molecular
19.
Mater Today Bio ; 25: 100955, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38312800

RESUMO

Tumor vaccines are emerging as one of the most promising therapeutic strategies for cancer treatment. With the advantages of low toxicity, convenient production and stable quality control, peptide vaccines have been widely used in preclinical and clinical trials involving various malignancies. However, when used alone, they still suffer from significant challenges including poor stability and immunogenicity as well as the low delivery efficiency, leading to limited therapeutic success. Herein, the STING-activating peptide nanovaccine based on human serum albumin (HSA) and biodegradable MnO2 was constructed, which can improve the stability and immunogenicity of antigenic peptides as well as facilitate their uptake by dendritic cells (DCs). Meanwhile, Mn2+ degraded from the nanovaccine can activate the STING pathway and further promote DCs maturation. In this way, the prepared nanovaccine can efficiently mediate T-cell immune responses, thereby exerting the effects of tumor prevention and therapy. Moreover, the prepared nanovaccine possesses the advantages of low cost, convenient preparation and good biocompatibility, showing great potential for practical applications.

20.
Adv Sci (Weinh) ; : e2400951, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38973319

RESUMO

Growing evidences have proved that tumors evade recognition and attack by the immune system through immune escape mechanisms, and PDL1/Pbrm1 genes have a strong correlation with poor response or resistance to immune checkpoint blockade (ICB) therapy. Herein, a multifunctional biomimetic nanocarrier (siRNA-CaP@PD1-NVs) is developed, which can not only enhance the cytotoxic activity of immune cells by blocking PD1/PDL1 axis, but also reduce tumor immune escape via Pbrm1/PDL1 gene silencing, leading to a significant improvement in tumor immunosuppressive microenvironment. Consequently, the nanocarrier promotes DC cell maturation, enhances the infiltration and activity of CD8+ T cells, and forms long-term immune memory, which can effectively inhibit tumor growth or even eliminate tumors, and prevent tumor recurrence and metastasis. Overall, this study presents a powerful strategy for co-delivery of siRNA drugs, immune adjuvant, and immune checkpoint inhibitors, and holds great promise for improving the effectiveness and safety of current immunotherapy regimens.

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