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1.
Mol Cell ; 82(22): 4246-4261.e11, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36400009

RESUMO

Acetyl-coenzyme A (acetyl-CoA) plays an important role in metabolism, gene expression, signaling, and other cellular processes via transfer of its acetyl group to proteins and metabolites. However, the synthesis and usage of acetyl-CoA in disease states such as cancer are poorly characterized. Here, we investigated global acetyl-CoA synthesis and protein acetylation in a mouse model and patient samples of hepatocellular carcinoma (HCC). Unexpectedly, we found that acetyl-CoA levels are decreased in HCC due to transcriptional downregulation of all six acetyl-CoA biosynthesis pathways. This led to hypo-acetylation specifically of non-histone proteins, including many enzymes in metabolic pathways. Importantly, repression of acetyl-CoA synthesis promoted oncogenic dedifferentiation and proliferation. Mechanistically, acetyl-CoA synthesis was repressed by the transcription factors TEAD2 and E2A, previously unknown to control acetyl-CoA synthesis. Knockdown of TEAD2 and E2A restored acetyl-CoA levels and inhibited tumor growth. Our findings causally link transcriptional reprogramming of acetyl-CoA metabolism, dedifferentiation, and cancer.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Camundongos , Animais , Acetilcoenzima A/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Histonas/metabolismo , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Carcinogênese/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo
2.
Med Res Rev ; 44(1): 422-452, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37470332

RESUMO

Soft tissue damage stimulates sympathetic nerves to release large amounts of catecholamine hormones which bind to ß-adrenergic receptors (ß-ARs) on the cell membrane surface. It activates the downstream effector molecules and impairs soft tissue wound healing. ß-blockers specifically inhibit ß-ARs activation in acute/chronic skin lesions and ulcerative hemangiomas. They also accelerate soft tissue wound healing by shortening the duration of inflammation, speeding keratinocyte migration and reepithelialization, promoting wound contraction and angiogenesis, and inhibiting bacterial virulence effects. In addition, ß-blockers shorten wound healing periods in patients with severe thermal damage by reducing the hypermetabolic response. While ß-blockers promote/inhibit corneal epithelial cell regeneration and restores limbal stem/progenitor cells function, it could well accelerate/delay corneal wound healing. Given these meaningful effects, a growing number of studies are focused on examining the efficacy and safety of ß-blockers in soft tissue wound repair, including acute and chronic wounds, severe thermal damage, ulcerated infantile hemangioma, corneal wounds, and other soft tissue disorders. However, an intensive investigation on their acting mechanisms is imperatively needed. The purpose of this article is to summerize the roles of ß-blockers in soft tissue wound healing and explore their clinical applications.


Assuntos
Antagonistas Adrenérgicos beta , Cicatrização , Humanos , Antagonistas Adrenérgicos beta/farmacologia , Antagonistas Adrenérgicos beta/uso terapêutico , Cicatrização/fisiologia , Receptores Adrenérgicos , Receptores Adrenérgicos beta
3.
BMC Microbiol ; 24(1): 142, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664612

RESUMO

BACKGROUND: The genomic information available for Pediococcus pentosaceus is primarily derived from fermented fruits and vegetables, with less information available from fermented meat. P. pentosaceus LL-07, a strain isolated from fermented meat, has the capability of producing exopolysaccharides (EPS). To assess the probiotic attributes of P. pentosaceus LL-07, we conducted whole-genome sequencing (WGS) using the PacBio SequelIIe and Illumina MiSeq platforms, followed by in vitro experiments to explore its probiotic potential. RESULTS: The genome size of P. pentosaceus LL-07 is 1,782,685 bp, comprising a circular chromosome and a circular plasmid. Our investigation revealed the absence of a CRISPR/Cas system. Sugar fermentation experiments demonstrated the characteristics of carbohydrate metabolism. P. pentosaceus LL-07 contains an EPS synthesis gene cluster consisting of 13 genes, which is different from the currently known gene cluster structure. NO genes associated with hemolysis or toxin synthesis were detected. Additionally, eighty-six genes related to antibiotic resistance were identified but not present in the prophage, transposon or plasmid. In vitro experiments demonstrated that P. pentosaceus LL-07 was comparable to the reference strain P. pentosaceus ATCC25745 in terms of tolerance to artificial digestive juice and bile, autoaggregation and antioxidation, and provided corresponding genomic evidence. CONCLUSION: This study confirmed the safety and probiotic properties of P. pentosaceus LL-07 via complete genome and phenotype analysis, supporting its characterization as a potential probiotic candidate.


Assuntos
Fermentação , Genoma Bacteriano , Pediococcus pentosaceus , Polissacarídeos Bacterianos , Probióticos , Pediococcus pentosaceus/genética , Pediococcus pentosaceus/metabolismo , Polissacarídeos Bacterianos/metabolismo , Polissacarídeos Bacterianos/biossíntese , Sequenciamento Completo do Genoma , Alimentos Fermentados/microbiologia , Carne/microbiologia , Família Multigênica , Genômica/métodos , Humanos , Plasmídeos/genética , Microbiologia de Alimentos
4.
J Hepatol ; 74(4): 794-800, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33188905

RESUMO

BACKGROUND & AIMS: HBeAg seroconversion during the natural history of chronic hepatitis B (CHB) is associated with a strong drop in serum HBV DNA levels and a reduction of intrahepatic covalently closed circular DNA (cccDNA) content. Of particular interest is the transition to HBeAg-negative chronic infection (ENCI). ENCI, previously known as inactive carrier state, is characterized by very low or negative viremia and the absence of liver disease. The molecular mechanisms responsible for the transition to ENCI and for the control of viral replication in ENCI are still poorly understood. METHODS: To identify which step(s) in the viral life cycle are controlled during the transition to ENCI, we quantified cccDNA, pre-genomic RNA (pgRNA), total HBV RNA and DNA replicative intermediates in 68 biopsies from patients in different phases of CHB. RESULTS: HBeAg seroconversion is associated with a reduction of cccDNA amounts as well as transcriptional activity. Silencing of cccDNA is particularly pronounced in ENCI, where there was ~46 times less pgRNA per cccDNA compared to HBeAg-negative CHB. Furthermore, a subgroup of patients with HBeAg-negative CHB can be characterized by reduced replication efficiency downstream of pgRNA. CONCLUSIONS: The reduction in serum viral load during the transition to ENCI seems to primarily result from strong inhibition of the transcriptional activity of cccDNA which can be maintained in the absence of liver disease. LAY SUMMARY: During the natural course of chronic hepatitis B virus infections, the immune response can gain control of viral replication. Quantification of viral DNA and RNA in liver biopsies of patients in different stages of chronic hepatitis B allowed us to identify the steps in the viral life cycle that are affected during the transition from active to inactive disease. Therapeutic targeting of these steps might induce sustained inhibition of viral transcription.


Assuntos
DNA Circular/análise , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B , Hepatite B Crônica , Ativação Transcricional/genética , Transcrição Viral/fisiologia , Replicação Viral/fisiologia , Biópsia , Portador Sadio/imunologia , Portador Sadio/virologia , DNA Viral/isolamento & purificação , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/imunologia , Hepatite B Crônica/patologia , Hepatite B Crônica/virologia , Humanos , Fenômenos do Sistema Imunitário , Fígado/patologia , Soroconversão/fisiologia , Carga Viral/imunologia
5.
Gastroenterology ; 154(6): 1778-1790, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29408639

RESUMO

BACKGROUND & AIMS: Most viruses are detected at early stages of cell infection and induce an innate immune response mediated by production of interferons (IFNs). IFNs induce expression of hundreds of IFN-stimulated genes (ISGs). Infection of chimpanzees with hepatitis C virus, but not hepatitis B virus (HBV), induces ISG expression in the liver. HBV might not induce an innate immune response because it is not detected by pattern recognition receptors (the stealth properties of HBV) or because HBV suppresses IFN production or signaling despite detection by pattern recognition receptors. We studied innate immune signaling in liver biopsies from patients with different stages of chronic HBV infection and uninfected individuals (controls). METHODS: We obtained liver within 10 minutes after collection from 30 patients with chronic HBV infection (hepatitis B e antigen-positive or -negative, with or without hepatitis) and 42 controls (most with fatty liver disease). The liver tissues were analyzed by histology, immunohistochemistry, quantitative reverse-transcription polymerase chain reaction, in situ hybridization, HBV RNA quantification, and HBV genotyping; some specimens were incubated with toll-like receptor (TLR) ligands (polyinosinic-polycytidylic acid) or infected with Sendai virus and then analyzed. RESULTS: Liver specimens from patients with HBV infection were not expressing more IFN or ISGs than those from control patients, indicating that chronic HBV infection did not activate an innate immune response. However, liver specimens from patients with HBV infection did produce IFN and induce expression of ISGs following activation of TLR3 with poly(I:C) or Sendai virus infections, so the innate immune response is not suppressed in these tissues. CONCLUSION: Liver tissues from patients with chronic HBV infection do not have induction of an innate immune response, but this response can be activated by other factors (TLR3 binding, Sendai virus infection) in HBV-infected liver tissue. These findings support the hypothesis that HBV is invisible to pattern recognition receptors.


Assuntos
Vírus da Hepatite B/imunologia , Hepatite B/imunologia , Hepatócitos/imunologia , Imunidade Inata/imunologia , Fígado/imunologia , Adulto , Biópsia , Estudos de Casos e Controles , Feminino , Hepatite B/patologia , Hepatite B/virologia , Hepatócitos/virologia , Humanos , Fatores Reguladores de Interferon/metabolismo , Interferons/biossíntese , Fígado/patologia , Fígado/virologia , Masculino
6.
Biomacromolecules ; 18(8): 2654-2662, 2017 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-28675926

RESUMO

Novel, biocompatible polyplexes, based on the combination of cationic pentablock copolymers with folic acid functionalized copolymers, were designed and developed for target-specific siRNA delivery. The resulting micelleplexes spontaneously formed polymeric micelles with a hydrophobic core surrounded directly by a cationic poly-2-(4-aminobutyl)-oxazole (PABOXA) and subsequently shielded by hydrophilic poly-2-methyl-oxazole (PMOXA) layer. The described micelleplexes form highly stable particles even in complete serum after 24 h compared with the highly cationic polymer PEI, which show aggregate formation in serum containing buffer solution. Targeted siRNA delivery and gene knockdown could be shown using green fluorescent protein (GFP) expressing HeLa cells, resulting in ∼31% and ∼8% suppression of the expression of GFP for targeted and nontargeted micelleplexes, respectively. Comparison studies of folic-receptor positive HeLa cells with normal folic-receptor-negative HEK293 cells revealed involvement of receptor mediated cellular uptake of fluorescently labeled siRNA. The new designed nanocarrier showed no cytotoxicity, having a potential application. The presented concept of shielding a nucleic-acid complexing cationic chains with a stealth layer and combining it with receptor ligand overcomes typical problems with undesired protein and cell interactions in delivery of nucleic acids using polymeric systems, opening new doors for application if RNA inhibition in the organism.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Receptores de Folato com Âncoras de GPI/metabolismo , Ácido Fólico , Micelas , Poliaminas , RNA Interferente Pequeno , Ácido Fólico/química , Ácido Fólico/farmacologia , Células HEK293 , Células HeLa , Humanos , Poliaminas/química , Poliaminas/farmacologia , RNA Interferente Pequeno/química , RNA Interferente Pequeno/farmacologia
7.
Nanotechnology ; 28(17): 175602, 2017 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-28291013

RESUMO

Cationic polymers as non-viral gene delivery carriers are widely used because of their strong condensing properties and long-term safety, but acute cytotoxicity is a persistent challenge. In this study, two types of polyplexes were prepared by co-formulating plasmid DNA and two cationic diblock copolymers PABOXA5-b-PMOXA33-PA (primary amine) and PABOXA5-b-PMOXA33-TA (tertiary amine) to check their transfection efficacies in HeLa cells and HEK293T cells, respectively. The plasmid DNA/PABOXA5-b-PMOXA33-PA polyplex showed higher transfection efficacy compared to the plasmid DNA/PABOXA5-b-PMOXA33-TA polyplex under an N/P ratio of 40. Both polymers exhibited low toxicity, attributed to the shielding effect of a hydrophilic, noncharged block. Mechanistic insight into differential transfection efficiencies of the polymers were gained by visualization and comparison of the condensates via transmission electron and atomic force microscopy. The results provide information suited for further structure optimization of polymers that are aimed for targeted gene delivery.


Assuntos
Plasmídeos/genética , Polímeros/química , Transfecção/métodos , Cátions , DNA/administração & dosagem , DNA/química , Células HEK293 , Células HeLa , Humanos , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Oxazóis/química , Polietilenoimina , Polímeros/síntese química , Polímeros/toxicidade
8.
J Immunol ; 188(11): 5283-92, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22544926

RESUMO

Vascular endothelial cells (EC) are an exposed tissue with intimate contact with circulating Ag-specific CTL. Experimental in vitro and clinical data suggested that endothelial cells present a different repertoire of MHC class I-restricted peptides compared with syngeneic leukocytes or epithelial cells. This endothelial-specific peptide repertoire might protect EC from CTL-mediated cell death. The HLA-A*02-restricted peptide profile of human EC and syngeneic B lymphoblastoid cells was biochemically analyzed and compared. For EC selective peptides, source protein expression, peptide binding affinity, and peptide-HLA-A*02 turnover were measured. The significance of abundant peptide presentation for target cell recognition by immunodominant CTL was tested by small interfering RNA treatment of EC to knock down the source proteins. High amounts of two peptides, PTRF(56-64) and CD59(106-114), were consistently detected in EC. This predominance of two endothelial peptides was explained by cell type-specific source protein expression that compensated for poor HLA-A*02 binding affinity and short half-live of peptide/HLA-A*02 complexes. Knocking down the source proteins containing the abundant endothelial peptide motifs led to a nearly 100-fold increase of surface expression of SMCY(311-319), an immunodominant minor histocompatibility Ag, as detected by cytotoxicity assays using SMCY(311-319)-specific CTL. We conclude that EC express and present preferentially two distinct HLA-A*02-restricted peptides at extraordinary high levels. These abundant self-peptides may protect EC from CTL-mediated lysis by competing for HLA-A*02 binding sites with immunodominant scarcely expressed antigenic peptides.


Assuntos
Endotélio Vascular/imunologia , Antígeno HLA-A2/fisiologia , Linfócitos T Citotóxicos/imunologia , Ligação Competitiva/imunologia , Linhagem Celular Tumoral , Células Cultivadas , Testes Imunológicos de Citotoxicidade , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Antígeno HLA-A2/biossíntese , Antígeno HLA-A2/metabolismo , Humanos , Epitopos Imunodominantes/biossíntese , Epitopos Imunodominantes/metabolismo , Epitopos Imunodominantes/fisiologia , Fragmentos de Peptídeos/biossíntese , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/fisiologia , Ligação Proteica/imunologia , Espectrometria de Massas por Ionização por Electrospray , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Citotóxicos/patologia
9.
Food Res Int ; 187: 114315, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763628

RESUMO

Paojiao, a typical Chinese traditional fermented pepper, is favored by consumers for its unique flavor profile. Microorganisms, organic acids, amino acids, and volatile compounds are the primary constituents influencing the development of paojiao's flavor. To elucidate the key flavor compounds and core microorganisms of Qicaipaojiao (QCJ), this study conducted a comprehensive analysis of the changes in taste substances (organic acids and amino acids) and volatile flavor compounds during QCJ fermentation. Key flavor substances in QCJ were identified using threshold aroma value and odor activity value and the core microorganisms of QCJ were determined based on the correlation between dominant microorganisms and the key flavor substances. During QCJ fermentation, 16 key taste substances (12 free amino acids and 4 organic acids) and 12 key aroma substances were identified. The fermentation process involved 10 bacteria and 7 fungal genera, including Lactiplantibacillus, Leuconostoc, Klebsiella, Pichia, Wickerhamomyces, and Candida. Correlation analysis revealed that the core functional microorganisms encompassed representatives from 8 genera, including 5 bacterial genera (Lactiplantibacillus, Weissella, Leuconostoc, Klebsiella, and Kluyvera) and 3 fungal genera (Rhodotorula, Phallus, and Pichia). These core functional microorganisms exhibited significant correlations with approximately 70 % of the key flavor substances (P < 0.05). This study contributes to an enhanced understanding of flavor formation mechanisms and offers valuable insight into flavor quality control in food fermentation processes.


Assuntos
Bactérias , Capsicum , Fermentação , Odorantes , Paladar , Compostos Orgânicos Voláteis , Capsicum/microbiologia , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo , Odorantes/análise , Bactérias/metabolismo , Bactérias/classificação , Microbiologia de Alimentos , Fungos/metabolismo , Fungos/classificação , Aminoácidos/análise , Aminoácidos/metabolismo , Alimentos Fermentados/microbiologia , Alimentos Fermentados/análise , Redes e Vias Metabólicas , Aromatizantes/metabolismo , Aromatizantes/análise
10.
Nanomedicine ; 9(6): 742-57, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23434677

RESUMO

Nanomedical approaches are a major transforming factor in medical diagnosis and therapies. Based on important earlier work in the field of liposomal drug delivery and metallic nanomaterials, the last decade has brought a broad array of new and improved intelligent nanoscale platforms which are not only suited to deliver drugs and imaging agents but also to carry advanced functionality including internal and external stimuli-responsiveness in a highly targeted fashion to a diseased area. This review focuses on required properties and differences of basic delivery platforms in regard to deliver smart functionality, on building blocks suited to enhance tissue-, cell- and receptor-specific targeting and on nano-bio interaction. Further it discusses advantages and disadvantages of those platforms for future clinical application with regard to the subject of complement activation and hypersensitivity reactions in particular against polyethylene glycol (PEG) and possible functionalization with nanosize switches. FROM THE CLINICAL EDITOR: This review focuses on the properties of platforms designed to deliver smart functionality, using appropriate building blocks to enhance tissue-, cell-, and receptor-specific targeting. The authors also discuss potential complications such as complement activation and hypersensitivity reactions, and possible functionalization with nanosize switches.


Assuntos
Portadores de Fármacos/química , Nanomedicina , Nanoestruturas/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Humanos , Lipossomos/química , Lipossomos/uso terapêutico , Nanopartículas/química , Nanopartículas/uso terapêutico , Nanoestruturas/química
11.
Food Chem X ; 19: 100828, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37780296

RESUMO

We explored the effect of microwave heating (MWH) and electric heating (ETH) on the volatile compounds (VCs) of pepper (Capsicum annuum L.). The spectral of the produced melanoidins by baking were used to screen samples with similar baking degrees. Mass spectrometry was used to detect the differences of VCs in samples. The results showed a dose-dependent effect between the intensity of absorption and fluorescence of melanoidins, which can be utilized as indicators for assessment baking degree. MWH samples produced larger variety of VCs than ETH. Changes in the variety and content of VCs infer changes in the flavor of pepper. According to the mechanism of Maillard reaction (MR) and MWH, it was deduced that MWH changes the type of chemical reaction in MR by affecting the distribution of valence electrons in the compounds. Therefore, MWH can be used as a novel method to modify the VCs and flavor of peppers.

12.
Tumour Biol ; 33(6): 1855-62, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22773373

RESUMO

This study investigated the anticancer effect and mechanism of salinomycin, a selective inhibitor of cancer stem cell, on human ovarian cancer cell line OV2008 in vitro and in vivo. The growth inhibitory effect of salinomycin on ovarian cancer cell line OV2008 was determined by measuring cell viability using the resazurin reduction assay. Apoptotic nuclear morphology was visualized by 4,6-diamino-2-phenylindole staining technique. The percentages of apoptotic cells and cell cycle parameters were detected by flow cytometry. The activity of p38 mitogen-activated protein kinase (p38 MAPK) was analyzed by Bio-Plex phosphoprotein assay. In vivo activity of salinomycin was assayed through tumor growth. Salinomycin caused concentration- (0.01-200 µM) and time-dependent (24-72 h) growth inhibitory effects in OV2008. Cell nuclear morphology observations showed that salinomycin-treated OV2008 cells displayed typical apoptotic characteristics. Salinomycin significantly increased the percentages of apoptotic cells in OV2008, showing a concentration- and time-dependent manner. There was no cell cycle arrest in the G1/G0, S, and G2/M phases between salinomycin-treated cells and control cells. Salinomycin also enhanced the phosphorylation of p38 MAPK. Moreover, salinomycin significantly inhibited the growth of the ovarian xenograft tumors. Salinomycin exhibited significant growth inhibition and induction of apoptosis in the human ovarian cancer cell line OV2008. The data suggested that salinomycin-induced apoptosis in OV2008 might be associated with activating p38 MAPK and merits further investigations.


Assuntos
Antibacterianos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Ovarianas/metabolismo , Piranos/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Western Blotting , Feminino , Citometria de Fluxo , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas
13.
Foods ; 11(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36076900

RESUMO

Suan Rou (SR), a traditional fermented meat, is widely favored by consumers due to its unique flavor and characteristics. To study the relationship between the core differential micro-organisms and differential volatile organic compounds (VOCs) of SR from six regions of China, high-throughput sequencing (HTS) and gas-chromatography−ion mobility spectrometry (GC-IMS) technologies were used to analyze the correlation between micro-organisms and VOCs in SR from Xiangxi of Hunan, Rongshui of Guangxi, Zunyi of Guizhou, Jinping of Guizhou, Congjiang of Guizhou, and Libo of Guizhou. A total of 13 core micro-organisms were identified at the genus level. Moreover, 95 VOCs were identified in the SR samples by GC-IMS analysis, with alcohols, aldehydes, ketones, and esters comprising the major VOCs among all the samples. The results showed a strong correlation (|r| > 0.8, p < 0.05) between the core differential micro-organisms and differential VOCs, including four bacteria, five fungi, and 12 VOCs. Pediococcus, Debaryomyces, Zygosaccharomyces, and Candida significantly contributed to the unique VOCs of SR.

14.
RSC Adv ; 12(46): 29928-29938, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36321106

RESUMO

Tannic acid (TA) is a natural phenolic compound abundant in plants. Its characteristics of low combustion and good absorption make it useful in the flame retardant field. On this basis, a new expansive flame retardant system (ACT) composed of ammonium polyphosphate (APP)/TA functional clay (CT) was used to study the synergistic flame retardancy and smoke suppression of natural rubber (NR). Because of their unique flame retardancy and better mechanical properties compared with the traditional expansive flame retardant system (IFR), new flame retardants have attracted much attention in various fields. The results of the cone calorimeter showed that the ACT system can significantly influence the decomposition behavior of NR and form a highly graphitized and phosphorous carbon layer to protect the composite material, thus a synergistic effect is produced on the flame retardancy and smoke suppression performance of the composite material. In addition, within the effective additive quality range of the ACT system, TC can give the NR composite excellent mechanical properties.

15.
Nat Commun ; 13(1): 2436, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35508466

RESUMO

Proteogenomic analyses of hepatocellular carcinomas (HCC) have focused on early-stage, HBV-associated HCCs. Here we present an integrated proteogenomic analysis of HCCs across clinical stages and etiologies. Pathways related to cell cycle, transcriptional and translational control, signaling transduction, and metabolism are dysregulated and differentially regulated on the genomic, transcriptomic, proteomic and phosphoproteomic levels. We describe candidate copy number-driven driver genes involved in epithelial-to-mesenchymal transition, the Wnt-ß-catenin, AKT/mTOR and Notch pathways, cell cycle and DNA damage regulation. The targetable aurora kinase A and CDKs are upregulated. CTNNB1 and TP53 mutations are associated with altered protein phosphorylation related to actin filament organization and lipid metabolism, respectively. Integrative proteogenomic clusters show that HCC constitutes heterogeneous subgroups with distinct regulation of biological processes, metabolic reprogramming and kinase activation. Our study provides a comprehensive overview of the proteomic and phophoproteomic landscapes of HCCs, revealing the major pathways altered in the (phospho)proteome.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteogenômica , Carcinoma Hepatocelular/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Mutação , Proteômica , beta Catenina/metabolismo
16.
Oncogenesis ; 10(7): 52, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34272356

RESUMO

Understanding the mechanisms underlying evasive resistance in cancer is an unmet medical need to improve the efficacy of current therapies. In hepatocellular carcinoma (HCC), aberrant expression of hypoxia-inducible factor 1 α (HIF1α) and increased aerobic glycolysis metabolism are drivers of resistance to therapy with the multi-kinase inhibitor Sorafenib. However, it has remained unknown how HIF1α is activated and how its activity and the subsequent induction of aerobic glycolysis promote Sorafenib resistance in HCC. Here, we report the ubiquitin-specific peptidase USP29 as a new regulator of HIF1α and of aerobic glycolysis during the development of Sorafenib resistance in HCC. In particular, we identified USP29 as a critical deubiquitylase (DUB) of HIF1α, which directly deubiquitylates and stabilizes HIF1α and, thus, promotes its transcriptional activity. Among the transcriptional targets of HIF1α is the gene encoding hexokinase 2 (HK2), a key enzyme of the glycolytic pathway. The absence of USP29, and thus of HIF1α transcriptional activity, reduces the levels of aerobic glycolysis and restores sensitivity to Sorafenib in Sorafenib-resistant HCC cells in vitro and in xenograft transplantation mouse models in vivo. Notably, the absence of USP29 and high HK2 expression levels correlate with the response of HCC patients to Sorafenib therapy. Together, the data demonstrate that, as a DUB of HIF1α, USP29 promotes Sorafenib resistance in HCC cells, in parts by upregulating glycolysis, thereby opening new avenues for therapeutically targeting Sorafenib-resistant HCC in patients.

17.
ACS Appl Bio Mater ; 3(10): 6919-6931, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-35019353

RESUMO

Nanomaterials allow designing targeted therapies, facilitate molecular diagnostics, and are therefore enabling platforms for personalized medicine. A systematic science and a predictive understanding of molecular/supramolecular structure relationships and nanoparticle structure/biological property relationships are needed for rational design and clinical progress but are hampered by the anecdotal nature, nonsystematic and nonrepresentative nanomaterial assortment, and oligo-disciplinary approach of many publications. Here, we find that a systematic and comprehensive multidisciplinary approach to production and exploration of molecular-structure/nanostructure relationship and nano-bio structure/function relationship of medical nanomaterials can be achieved by combining systematic chemical synthesis, thorough physicochemical analysis, computer modeling, and biological experiments, as shown in a nanomaterial family of amphiphilic, micelle-forming oxazoline/siloxane block copolymers suited for the clinical application. This comprehensive interdisciplinary approach leads to improved understanding of nanomaterial structures, allows good insights into binding modes for the nanomaterial protein corona, induces the design of minimal cell-binding materials, and yields rational strategies to avoid toxicity. Thus, this work contributes to a systematic and scientific basis for rational design of medical nanomaterials.

18.
Hepatol Commun ; 3(7): 971-986, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31334445

RESUMO

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths worldwide. Treatment options for patients with advanced-stage disease are limited. A major obstacle in drug development is the lack of an in vivo model that accurately reflects the broad spectrum of human HCC. Patient-derived xenograft (PDX) tumor mouse models could overcome the limitations of cancer cell lines. PDX tumors maintain the genetic and histologic heterogeneity of the originating tumors and are used for preclinical drug development in various cancers. Controversy exists about their genetic and molecular stability through serial passaging in mice. We aimed to establish PDX models from human HCC biopsies and to characterize their histologic and molecular stability during serial passaging. A total of 54 human HCC needle biopsies that were derived from patients with various underlying liver diseases and tumor stages were transplanted subcutaneously into immunodeficient, nonobese, diabetic/severe combined immunodeficiency gamma-c mice; 11 successfully engrafted. All successfully transplanted HCCs were Edmondson grade III or IV. HCC PDX tumors retained the histopathologic, transcriptomic, and genomic characteristics of the original HCC biopsies over 6 generations of retransplantation. These characteristics included Edmondson grade, expression of tumor markers, tumor gene signature, tumor-associated mutations, and copy number alterations. Conclusion: PDX mouse models can be established from undifferentiated HCCs, with an overall success rate of approximately 20%. The transplanted tumors represent the entire spectrum of the molecular landscape of HCCs and preserve the characteristics of the originating tumors through serial passaging. HCC PDX models are a promising tool for preclinical personalized drug development.

19.
Nanoscale ; 7(40): 16983-93, 2015 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-26415866

RESUMO

Translation of therapeutic polymeric nanosystems to patients and industry requires simplified, reproducible and scalable methods for assembly and loading. A single-step in-line process based on nanocoprecipitation of oxazoline-siloxane block copolymers in flow-focusing poly(dimethylsiloxane) microfluidics was designed to manufacture injection-ready nanosystems. Nanosystem characteristics could be controlled by copolymer concentration, block length and chemistry, microchannel geometry, flow rate, aqueous/organic flow rate ratio and payload concentration. The well-tolerated nanosystems exhibited differential cell binding and payload delivery and could confer sensitivity to photodynamic therapy to HeLa cancer cells. Such injection-ready nanosystems carrying drugs, diagnostic or functional materials may facilitate translation to clinical application.


Assuntos
Diagnóstico por Imagem/métodos , Portadores de Fármacos , Técnicas Analíticas Microfluídicas/métodos , Nanopartículas/química , Neoplasias , Fotoquimioterapia/métodos , Dimetilpolisiloxanos/síntese química , Dimetilpolisiloxanos/química , Dimetilpolisiloxanos/farmacologia , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Células HeLa , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/patologia
20.
Yao Xue Xue Bao ; 38(4): 279-82, 2003 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-12889128

RESUMO

AIM: To develop a sensitive and specific HPLC method for determination of trigonelline in rabbit plasma, and study the pharmacokinetics in rabbit. METHODS: After ig of fenugreek extract and i.v. of trigonelline in rabbit, the biological samples could be well purified after precipitation of protein with methanol and acetonitrile. Asahipak NH2P-50 column was used, the mobile phase consisted of acetonitrile-water (90:10) at a flow-rate of 1.2 mL.min-1, and detection wavelength was set at UV 265 nm. The column temperature is 30 degrees C. RESULTS: The calibration curve was linear in the range from 0.98 mg.L-1 to 31.28 mg.L-1, with r = 0.9986, the detection limit of this method was 50 micrograms.L-1. The concentration-time curves of trigonelline in rabbits after ig and i.v. administration were shown to fit one-compartment and two-compartment open model, respectively. The main parameters after ig of fenugreek extract were as follow: T1/2(Ka) was 0.9 h, T1/2(Ke) was 2.2 h, V was 0.64 L.kg-1, AUC was 1.93 mg.min.L-1. The main parameters after i.v. of trigonelline were as follows: T1/2 alpha was 10.8 min, T1/2 beta was 44.0 min, K21 was 0.044 min-1, K10 was 0.026 min-1, K12 was 0.017 min-1, AUC was 931.0 mg.min.L-1. CONCLUSION: Trigonelline showed a middle rate of absorption and fast rate of elimination in rabbit. Meanwhile, the method is simple, accurate, with a good reproducibility, and it provide a basic method for the investigation of trigonelline and fenugreek pharmacokinetics.


Assuntos
Alcaloides/farmacocinética , Medicamentos de Ervas Chinesas/farmacocinética , Trigonella/química , Alcaloides/sangue , Alcaloides/isolamento & purificação , Animais , Antineoplásicos Fitogênicos/sangue , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacocinética , Área Sob a Curva , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/isolamento & purificação , Feminino , Masculino , Plantas Medicinais/química , Coelhos , Sementes/química
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