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1.
J Am Chem Soc ; 146(33): 23121-23137, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-38980064

RESUMO

Addressing the global challenge of bacterial resistance demands innovative approaches, among which multitargeting is a widely used strategy. Current strategies of multitargeting, typically achieved through drug combinations or single agents inherently aiming at multiple targets, face challenges such as stringent pharmacokinetic and pharmacodynamic requirements and cytotoxicity concerns. In this report, we propose a bacterial-specific global disruption approach as a vastly expanded multitargeting strategy that effectively disrupts bacterial subcellular organization. This effect is achieved through a pioneering chemical design of ligand-receptor interaction-induced aggregation of small molecules, i.e., DNA-induced aggregation of a diarginine peptidomimetic within bacterial cells. These intracellular aggregates display affinity toward various proteins and thus substantially interfere with essential bacterial functions and rupture bacterial cell membranes in an "inside-out" manner, leading to robust antibacterial activities and suppression of drug resistance. Additionally, biochemical analysis of macromolecule binding affinity, cytoplasmic localization patterns, and bacterial stress responses suggests that this bacterial-specific intracellular aggregation mechanism is fundamentally different from nonselective classic DNA or membrane binding mechanisms. These mechanistic distinctions, along with the peptidomimetic's selective permeation of bacterial membranes, contribute to its favorable biocompatibility and pharmacokinetic properties, enabling its in vivo antimicrobial efficacy in several animal models, including mice-based superficial wound models, subcutaneous abscess models, and septicemia infection models. These results highlight the great promise of ligand-receptor interaction-induced intracellular aggregation in achieving a globally disruptive multitargeting effect, thereby offering potential applications in the treatment of malignant cells, including pathogens, tumor cells, and infected tissues.


Assuntos
Antibacterianos , Ligantes , Animais , Antibacterianos/farmacologia , Antibacterianos/química , Camundongos , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana/efeitos dos fármacos , Peptidomiméticos/farmacologia , Peptidomiméticos/química , Separação de Fases
2.
Wei Sheng Yan Jiu ; 53(2): 243-256, 2024 Mar.
Artigo em Zh | MEDLINE | ID: mdl-38604960

RESUMO

OBJECTIVE: To understand the prevalence, genetic characteristics and drug resistance features of Salmonella Kentucky ST314 in Shenzhen. METHODS: Whole genome sequencing of 14 strains of Salmonella Kentucky ST314 collected from 2010-2021 by the Foodborne Disease Surveillance Network of Shenzhen Center for Disease Control and Prevention for phylogenetic evolutionary analysis, drug resistance gene and plasmid detection; drug susceptibility experiments were performed by micro-broth dilution method. RESULTS: A total of 57 strains of Salmonella Kentucky were collected from the foodborne disease surveillance network, 14 of which were ST314. The Shenzhen isolates were clustered with isolates from Southeast Asian countries such as Vietnam and Thailand on clade 314.2, and the single nucleotide polymorphism distance between local strains in Shenzhen was large, indicating dissemination. In this study, a total of 17 drug resistance genes/mutations in 9 categories were detected in the genome of Salmonella Kentucky ST314, carrying 3 extended spectrum beta-lactamases(ESBLs), including bla_(CTX-M-24)(14.3%, 2/14), bla_(CTX-M-55)(7.1%, 1/14), and bla_(CTX-M-130)(14.3%, 2/14), all located on plasmids. Regarding quinolone resistance factors, two plasmid-mediated quinolone resistance(PMQR) genes were identified in the genome: qnrB6(71.4%, 10/14) and aac(6')Ib-cr(78.6%, 11/14), a quinolone resistance quinolone resistance-determining regions(QRDR) mutation T57 S(100%, 14/14). The multi-drug resistance rate of Salmonella Kentucky ST314 in Shenzhen was 92.86%(13/14)with the highest rate of resistance to tetracycline and cotrimoxazole(100%, 14/14), followed by chloramphenicol(92.86%, 13/14), cefotaxime and ampicillin(78.57%, 11/14), ciprofloxacin and nalidixic acid(71.43%, 10/14), and ampicillin-sulbactam had the lowest resistance rate(21.43%, 3/14). CONCLUSION: ST314 is the second most prevalent ST type among Salmonella Kentucky in Shenzhen, mainly isolated from food, especially poultry; phylogenetic analysis suggests that ST314 is a disseminated infection and the genome shows a highly genetically conserved phenotype. Drug resistance of Salmonella Kentucky ST314 is very serious, especially QRDR mutation, PMQR gene co-mediated quinolone resistance and plasmid-mediated cephalosporin resistance are prominent and deserve extensive attention.


Assuntos
Doenças Transmitidas por Alimentos , Quinolonas , Humanos , Kentucky , Filogenia , Salmonella , Antibacterianos/farmacologia , Plasmídeos/genética , Resistência a Medicamentos , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana Múltipla/genética , beta-Lactamases/genética
3.
Ecotoxicol Environ Saf ; 242: 113925, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35917710

RESUMO

Manganese (Mn) is a common environmental pollutant. Mn exposure can lead to neurodegenerative diseases resembling Parkinson's disease, and has become a major public health concern. However, the mechanism of Mn-induced neurotoxicity in the brain is not clear. Fecal microbiome transplantation (FMT) may alleviate the neurotoxicity of Mn exposure by remodeling the gut microbiota. In this study, MnCl2 (manganese chloride) was administered to mice as in drinking water (Mn: 200 mg/L), and fecal matter from donor mice was administered by oral gavage every other day to the recipient mice. The Mn exposure model (Mn group) and FMT model (Mn+FMT group) were established and analyzed 5 weeks post-exposure. The Wipi1 gene exhibited the most significant increase associated with Mn exposure and Mn+FMT treatment groups based on transcriptome analysis. Combined analysis of transcriptomics and proteomics demonstrated that the apelin signaling pathway is the main pathway affected by FMT during Mn exposure. Immunofluorescence and Western blot showed that the expression of key proteins (Beclin-1, LC-3B, and PINK1) associated with autophagy in the hippocampus was robustly activated in the Mn exposure group, but attenuation was observed in Mn+FMT mice, suggesting a critical role of autophagy in neurotoxicity induced by Mn exposure. Our research provides evidence for the neurotoxic effects of Mn exposure through autophagy activation and provides an underlying mechanism of FMT protection against Mn-induced neurotoxicity through regulation of the apelin signaling pathway.


Assuntos
Transplante de Microbiota Fecal , Síndromes Neurotóxicas , Animais , Apelina , Autofagia , Encéfalo , Manganês/toxicidade , Camundongos , Transdução de Sinais
4.
Biochem Biophys Res Commun ; 525(4): 863-869, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32171522

RESUMO

Evidences suggest that dietary docosahexaenoic acid (DHA) supplementation may have pleiotropic beneficial effects on health. However, the underlying mechanisms and crucial targets that are involved in achieving these benefits remain to be clarified. In this study, we employed biochemical analysis and liquid chromatography-mass spectrometry (LC-MS) based untargeted metabolomics coupled with multivariate statistical analysis to identify potential metabolic targets of DHA in adult rats at 48 h post-feeding. Blood biochemical analysis showed a significant decrease in triglyceride level of DHA diet group, the untargeted metabolomic analysis revealed that some metabolites were significantly different between the DHA diet group and the basal diet group, including fatty acids (16:0, 18:1, 20:5n3, 22:2n6 and 24:0), diglyceride (20:0/18:2n6, 18:3n6/22:6n3, 20:4n3/20:4n3, and 22:0/24:0), PIP2 (18:2/20:3), phytol, lysoSM (d18:1), 12-hydroxyheptadecatrienoic acid, dihydrocorticosterone and N1-acetylspermine, which are mainly involved in fat mobilization and triglyceride hydrolysis, arachidonic acid, steroid hormone, and polyamine metabolism. To our knowledge, this is the first report that links the metabolic effects of DHA with arachidonic acid, steroid, and polyamine metabolism. Our finding suggests that the beneficial effects of DHA, may not directly require its own metabolic derivatives, but could be achieved by metabolic regulation.


Assuntos
Ácido Araquidônico/sangue , Ácidos Docosa-Hexaenoicos/metabolismo , Ácidos Docosa-Hexaenoicos/farmacologia , Triglicerídeos/sangue , Animais , Análise Química do Sangue , Cromatografia Líquida , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/sangue , Análise dos Mínimos Quadrados , Espectrometria de Massas/estatística & dados numéricos , Poliaminas/sangue , Ratos , Reprodutibilidade dos Testes
5.
Helicobacter ; 25(2): e12682, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32088934

RESUMO

BACKGROUND: To investigate the effect of a social media platform for the treatment of Helicobacter pylori infection. MATERIALS AND METHODS: We enrolled 222 patients from October 2018 to June 2019, who required H pylori therapy. We used WeChat, a social media platform, as a patient reminder tool. They were randomly divided into the intervention and control groups (n = 111 per group) to compare and evaluate their disease awareness, medication adherence, incidence of adverse drug reactions, and H pylori eradication rate. RESULTS: Patients in the intervention group had significantly better disease-related knowledge, medication adherence, and H pylori eradication rates than those in the control group (P < .05). CONCLUSIONS: Using a social media platform may improve treatment rates of H pylori infection.


Assuntos
Antibacterianos/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Mídias Sociais/organização & administração , Adulto , Testes Respiratórios , Esquema de Medicação , Quimioterapia Combinada , Feminino , Humanos , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Cooperação do Paciente , Resultado do Tratamento
6.
Bioprocess Biosyst Eng ; 42(5): 817-827, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30758672

RESUMO

Menaquinone-7 (MK-7) plays an important role in blood clotting, cardiovascular disease and anti-osteoporosis, and has been wildly used in the food additives and pharmaceutical industries. The aim of this study was to investigate the mechanism of menaquinone-7 biosynthesis in response to different oxygen supplies in Bacillus natto. The differences of fermentation performance, intracellular metabolites, oxidative stress reaction and enzyme activities of Bacillus natto R127 were analyzed under different KLa. Glycerol consumption rate and MK-7 yield at 24.76 min- 1 was 2.1 and 7.02 times of that at 18.23 min- 1. Oxidative stress analysis showed the cell generated more active oxygen and possessed higher antioxidant capacity at high oxygen supply condition. Meanwhile, high pyruvate kinase and high cytochrome c oxidase activities were also observed at 24.76 min- 1. Furthermore, comparative metabolomics analyses concluded series of biomarkers for high MK-7 biosynthesis and cell rapid growth. Besides, several metabolic responses including low glyceraldehyde-3-phosphate accumulation, low flux from pyruvate to lactic acid, high active TCA pathway, were also found to be associated with high MK-7 accumulation at high oxygen supply conditions. These findings provided the information for better understanding of oxygen effect on MK-7 biosynthesis and lay a foundation for further improvement of MK-7 production as well.


Assuntos
Bacillus subtilis/metabolismo , Glicerol/metabolismo , Estresse Oxidativo , Consumo de Oxigênio , Oxigênio/metabolismo , Vitamina K 2/análogos & derivados , Vitamina K 2/metabolismo
7.
J Sep Sci ; 40(6): 1334-1342, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28106326

RESUMO

A novel oil-in-salt liquid-phase microextraction was developed and introduced for the extraction and concentration of the trace levels of active alkaloids in Coptis chinensis prior to being analyzed by high-performance liquid chromatography with ultraviolet detection. Also, the oil-in-salt extraction mechanism was analyzed, the enrichment factor and extraction recovery were redefined, and the proposed method was compared with other methods. In the approach, the mixed solvent of pentanol/octanol (6:4, v/v) and NaCl (20% w/v) are immobilized on the permutite surface in turn to form oil-in-salt double membranes, through which the target analytes can be molecularized though salting-out effect and be extracted by organic solvent. The main parameters affecting the approach were investigated and optimized. Under the optimized conditions, the enrichment factors of the analytes were 30-117, the linear ranges were 0.002-2 µg/mL for jatrorrhizine, coptisine, and palmatine, and 0.001-3 µg/mL for berberine (r2 ≥ 0.9923). The limits of detection were less than 1 ng/mL. Satisfactory recoveries (84.3%-120.3%) and precision (0.9%-7.5%) were also obtained. These results confirm that the approach is a simple and reliable sample pretreatment procedure and allows for the quantification of active alkaloids in C. chinensis at actual concentration levels.


Assuntos
Alcaloides/análise , Coptis/química , Medicamentos de Ervas Chinesas/química , Cromatografia Líquida de Alta Pressão , Microextração em Fase Líquida
8.
Sci Adv ; 10(30): eadp4872, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39058779

RESUMO

Amid rising antibiotic resistance, the quest for advanced antibacterial agents to surpass microbial adaptation is paramount. This study introduces Pyrgos[n]cages (n = 1 to 4), pioneering multidecker cationic covalent organic cages engineered to combat drug-resistant bacteria via a dual-targeting approach. Synthesized through successive photocatalytic bromination and cage-forming reactions, these architectures stand out for their dense positive charge distribution, exceptional stability, and substantial rigidity. Pyrgos[n]cages exhibit potent bactericidal activity by disrupting bacterial membrane potential and binding to DNA. Notably, these structures show unparalleled success in eradicating both extracellular and intracellular drug-resistant pathogens in diverse infection scenarios, with antibacterial efficiency markedly increasing over 100-fold as the decker number rises from 1 to 3. This study provides an advance in antibacterial tactics and underscores the transformative potential of covalent organic cages in devising enduring countermeasures against antibiotic-resistant microbial threats.


Assuntos
Antibacterianos , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/química , Farmacorresistência Bacteriana/efeitos dos fármacos , Humanos , Bactérias/efeitos dos fármacos
9.
Sci Adv ; 10(23): eado1550, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38848358

RESUMO

The utilization of three-dimensional (3D) bioprinting technology to create a transplantable bioartificial liver emerges as a promising remedy for the scarcity of liver donors. This study outlines our strategy for constructing a 3D-bioprinted liver, using in vitro-expanded primary hepatocytes recognized for their safety and enhanced functional robustness as hepatic cell sources for bioartificial liver construction. In addition, we have developed bioink biomaterials with mechanical and rheological properties, as well as printing capabilities, tailored for 3D bioprinting. Upon heterotopic transplantation into the mesentery of tyrosinemia or 90% hepatectomy mice, our 3D-bioprinted liver effectively restored lost liver functions, consequently extending the life span of mice afflicted with liver injuries. Notably, the inclusion of an artificial blood vessel in our 3D-bioprinted liver allowed for biomolecule exchange with host blood vessels, demonstrating, in principle, the rapid integration of the bioartificial liver into the host vascular system. This model underscores the therapeutic potential of transplantation for the treatment of liver failure diseases.


Assuntos
Bioimpressão , Hepatócitos , Falência Hepática , Fígado , Impressão Tridimensional , Animais , Hepatócitos/metabolismo , Hepatócitos/transplante , Camundongos , Bioimpressão/métodos , Fígado/metabolismo , Falência Hepática/terapia , Engenharia Tecidual/métodos , Transplante de Fígado/métodos , Fígado Artificial , Modelos Animais de Doenças , Tirosinemias/terapia , Tirosinemias/metabolismo , Alicerces Teciduais/química
10.
Adv Sci (Weinh) ; 11(21): e2309166, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38493495

RESUMO

The construction of bioartificial livers, such as liver organoids, offers significant promise for disease modeling, drug development, and regenerative medicine. However, existing methods for generating liver organoids have limitations, including lengthy and complex processes (taking 6-8 weeks or longer), safety concerns associated with pluripotency, limited functionality of pluripotent stem cell-derived hepatocytes, and small, highly variable sizes (typically ≈50-500 µm in diameter). Prolonged culture also leads to the formation of necrotic cores, further restricting size and function. In this study, a straightforward and time-efficient approach is developed for creating rapid self-assembly mini-livers (RSALs) within 12 h. Additionally, primary hepatocytes are significantly expanded in vitro for use as seeding cells. RSALs exhibit consistent larger sizes (5.5 mm in diameter), improved cell viability (99%), and enhanced liver functionality. Notably, RSALs are functionally vascularized within 2 weeks post-transplantation into the mesentery of mice. These authentic hepatocyte-based RSALs effectively protect mice from 90%-hepatectomy-induced liver failure, demonstrating the potential of bioartificial liver-based therapy.


Assuntos
Modelos Animais de Doenças , Hepatectomia , Hepatócitos , Falência Hepática , Animais , Camundongos , Hepatectomia/métodos , Falência Hepática/prevenção & controle , Falência Hepática/induzido quimicamente , Fígado Artificial , Fígado/cirurgia , Organoides , Masculino , Camundongos Endogâmicos C57BL
11.
ACS Appl Mater Interfaces ; 15(17): 20603-20612, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37078734

RESUMO

The ability to accurately characterize microorganism distribution in the intestinal tract is helpful for understanding intrinsic mechanisms. Within the intestine, traditional optical probes used for microorganism labeling commonly suffer from a low imaging penetration depth and poor resolution. We report a novel observation tool useful for microbial research by labeling near-infrared-IIb (NIR-IIb, 1500-1700 nm) lanthanide nanomaterials NaGdF4:Yb3+,Er3+@NaGdF4,Nd3+ (Er@Nd NPs) onto the surface of Lactobacillus bulgaricus (L. bulgaricus) via EDC-NHS chemistry. We monitor microorganisms in tissue by two-photon excitation (TPE) microscopy and in vivo with NIR-IIb imaging. This dual-technique approach offers great potential for determining the distribution of transplanted bacteria in the intestinal tract with a higher spatiotemporal resolution.


Assuntos
Intestinos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Microscopia de Fluorescência/métodos , Lactobacillus/metabolismo , Intestinos/química , Intestinos/metabolismo , Probióticos/metabolismo , Probióticos/farmacologia , Feminino , Animais , Camundongos , Camundongos Endogâmicos ICR
12.
Nat Commun ; 14(1): 6567, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848496

RESUMO

Human serum albumin (HSA) based drug delivery platforms that feature desirable biocompatibility and pharmacokinetic property are rapidly developed for tumor-targeted drug delivery. Even though various HSA-based platforms have been established, it is still of great significance to develop more efficient preparation technology to broaden the therapeutic applications of HSA-based nano-carriers. Here we report a bridging strategy that unfastens HSA to polypeptide chains and subsequently crosslinks these chains by a bridge-like molecule (BPY-Mal2) to afford the HSA reassemblies formulation (BPY@HSA) with enhanced loading capacity, endowing the BPY@HSA with uniformed size, high photothermal efficacy, and favorable therapeutic features. Both in vitro and in vivo studies demonstrate that the BPY@HSA presents higher delivery efficacy and more prominent photothermal therapeutic performance than that of the conventionally prepared formulation. The feasibility in preparation, stability, high photothermal conversion efficacy, and biocompatibility of BPY@HSA may facilitate it as an efficient photothermal agents (PTAs) for tumor photothermal therapy (PTT). This work provides a facile strategy to enhance the loading capacity of HSA-based crosslinking platforms in order to improve delivery efficacy and therapeutic effect.


Assuntos
Nanopartículas , Neoplasias , Humanos , Albumina Sérica Humana/química , Terapia Fototérmica , Linhagem Celular Tumoral , Neoplasias/terapia , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Fototerapia
13.
Int J Antimicrob Agents ; 62(3): 106896, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37343807

RESUMO

Highly fluoroquinolone-resistant Salmonella enterica serotype Kentucky has become widespread in recent years, largely associated with the spread of sequence type 198 (ST198), which often leads to multidrug resistance. Research on the genomic epidemiology of Salmonella Kentucky in China is currently uncommon. In this study, we analysed the genomic epidemiology and antimicrobial resistance characteristics of Salmonella Kentucky ST198 collected from foodborne disease surveillance in Shenzhen, China, during 2010-2021, using whole-genome sequencing and antibiotic susceptibility testing. In addition, 158 global Salmonella Kentucky ST198 genomes were included for comparison. Among 8559 Salmonella isolates, 43 Salmonella Kentucky ST198 isolates were detected during 2010-2021. The global Salmonella Kentucky ST198 evolutionary tree was divided into five clades, with Shenzhen isolates distributed in clades 198.1, 198.2-1 and 198.2-2, mainly clustered with Chinese strains. Strains in clade 198.2 dominated in Shenzhen and all of them showed multidrug resistance. Nine strains showed high resistance to ceftriaxone, which was associated with blaCTX-M-14b in clade 198.2-1, which was demonstrated to be located on the chromosome. Fifteen strains showed high resistance to ciprofloxacin, which was associated with carriage of qnrS1 in clade 198.2-2. qnrS1 was first located on an IncHI2 plasmid and then transferred into the chromosome. Here we report the genomic and antimicrobial resistance characterisation of Salmonella Kentucky ST198 in Shenzhen. Of particular concern, we identified for the first time a clade 198.2-1 isolate carrying blaCTX-M-14b as well as chromosomally located qnrS1 in clade 198.2-2 of Salmonella Kentucky ST198 in China, highlighting the necessity of surveillance of clade 198.2.


Assuntos
Infecções por Salmonella , Salmonella enterica , Humanos , Antibacterianos/farmacologia , Salmonella enterica/genética , Sorogrupo , Infecções por Salmonella/epidemiologia , Kentucky , Farmacorresistência Bacteriana Múltipla/genética
14.
Nano Lett ; 11(7): 2944-8, 2011 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-21675715

RESUMO

Anthraquinone self-assembles on Cu(111) into a giant honeycomb network with exactly three molecules on each side. Here we propose that the exceptional degree of order achieved in this system can be explained as a consequence of the confinement of substrate electrons in the pores, with the pore size tailored so that the confined electrons can adopt a noble-gas-like two-dimensional quasi-atom configuration with two filled shells. Formation of identical pores in a related adsorption system (at different overall periodicity due to the different molecule size) corroborates this concept. A combination of photoemission spectroscopy with density functional theory computations (including van der Waals interactions) of adsorbate-substrate interactions allows quantum mechanical modeling of the spectra of the resultant quasi-atoms and their energetics.


Assuntos
Antraquinonas/química , Cobre/química , Gases/química , Nanotecnologia , Tamanho da Partícula , Espectroscopia Fotoeletrônica , Teoria Quântica , Propriedades de Superfície
15.
J Control Release ; 352: 450-458, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36341929

RESUMO

Natural killer (NK) cells exert cytotoxic effects against infected or stressed cells, such as tumor cells, without the limitation of major histocompatibility complex (MHC) I. NK cells secrete perforins to form tunnels to mediate the entry of granzyme into target cells. This strategy, selected by natural evolution, provides a feasible method for the delivery of antitumor drugs against intracellular targets, and avoids drug-resistant mechanisms in tumor cells, such as the pumping out of drugs mediated by multidrug resistance. We constructed pH-labile artificial NK cells (ANKC) based on nature to mediate high levels of drugs in tumor cells to overcome tumor drug resistance. Mesoporous silicon nanoparticles (MSNs) modified with benzaldehyde were designed to function as scaffolds for ANKC. Doxorubicin (Dox), a model antitumor drug, was loaded into the pores of MSNs. Melittin, a pore-forming peptide, was utilized as the gate for mesopores with an acid-labile Schiff base linkage. pH-labile ANKC released melittin and Dox in slightly acidic tumor microenvironments. Melittin, like perforin, assembled tunnels on the plasma membrane or endosome, ensuring the intracellular transportation of Dox. Dox, similar to granzyme, induced the apoptosis of tumor cells. The combinational treatment partially eased the drug resistance mechanism, such as pumping out of drugs, by continuous intracellular drug accumulation mediated by melittin pores. The pH-labile ANKC demonstrated significant Dox enrichment in drug-resistant MCF-7/Adr cells and MCF-7/Adr-based xenograft tumors in a mouse model, which eventually contributed to efficient inhibition of the proliferation and growth of MCF-7/Adr tumors. PH-labile ANKC provided a potential strategy to treat drug-resistant tumors.


Assuntos
Antineoplásicos , Neoplasias da Mama , Nanopartículas , Camundongos , Animais , Humanos , Feminino , Meliteno/farmacologia , Granzimas , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Células MCF-7 , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Concentração de Íons de Hidrogênio , Células Matadoras Naturais , Neoplasias da Mama/tratamento farmacológico , Microambiente Tumoral
16.
Nat Commun ; 13(1): 5237, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-36068222

RESUMO

Protein kinase-mediated phosphorylation plays a critical role in many biological processes. However, the identification of key regulatory kinases is still a great challenge. Here, we develop a trans-omics-based method, central kinase inference, to predict potentially key kinases by integrating quantitative transcriptomic and phosphoproteomic data. Using known kinases associated with anti-cancer drug resistance, the accuracy of our method denoted by the area under the curve is 5.2% to 29.5% higher than Kinase-Substrate Enrichment Analysis. We further use this method to analyze trans-omic data in hepatocyte maturation and hepatic reprogramming of human dermal fibroblasts, uncovering 5 kinases as regulators in the two processes. Further experiments reveal that a serine/threonine kinase, PIM1, promotes hepatic conversion and protects human dermal fibroblasts from reprogramming-induced ferroptosis and cell cycle arrest. This study not only reveals new regulatory kinases, but also provides a helpful method that might be extended to predict central kinases involved in other biological processes.


Assuntos
Ferroptose , Ciclo Celular , Pontos de Checagem do Ciclo Celular/genética , Resistencia a Medicamentos Antineoplásicos , Ferroptose/genética , Humanos , Fosforilação , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas c-pim-1/genética , Proteínas Proto-Oncogênicas c-pim-1/metabolismo
17.
Front Microbiol ; 13: 1065672, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36605513

RESUMO

Salmonella enterica subsp. enterica serovar Derby (S. Derby) is one of the most common serotypes responsible for salmonellosis in humans and animals. The two main sequence types (ST) observed in China are ST40 and ST71, with ST40 presently being the most common in Shenzhen. Recent years have seen an increasing number of cases of salmonella caused by ST40 S. Derby, but the epidemiology is not clear. We gathered 314 ST40 S. Derby isolates from food and patient samples for 11 years in Shenzhen; 76 globally prevalent representative strains were also collected. Whole-genome sequencing (WGS) combined with drug resistance phenotyping was used to examine population structural changes, inter-host associations, drug resistance characteristics, and the food-transmission risks of ST40 S. Derby in Shenzhen over this period. The S. enterica evolutionary tree is divided into five clades, and the strains isolated in Shenzhen were primarily concentrated in Clades 2, 4, and 5, and thus more closely related to strains from Asian (Thailand and Vietnam) than European countries. Our 11-year surveillance of S. Derby in Shenzhen showed that Clades 2, 4, and 5 are now the dominant epidemic branches, and branches 2 and 5 are heavily multi-drug resistant. The main resistance pattern is ampicillin-tetracycline-ciprofloxacin-chloramphenicol-nalidixic acid-streptomycin-sulfamethoxazole/trimethoprim. This may lead to a trend of increasing resistance to ST40 S. Derby in Shenzhen. Using a segmentation of ≤3 SNP among clone clusters, we discovered that Clades 2 and 4 contained multiple clonal clusters of both human- and food-derived strains. The food-derived strains were mainly isolated from pig liver, suggesting this food has a high risk of causing disease outbreaks in Shenzhen.

18.
J Chem Phys ; 135(13): 134705, 2011 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21992333

RESUMO

3-phenyl-propynenitrile (PPN) adsorbs on Cu(111) in a hexagonal network of molecular trimers formed through intermolecular interaction of the cyano group of one molecule with the aromatic ring of its neighbor. Heptamers of trimers coalesce into interlocking pinwheel-shaped structures that, by percolating across islands of the original trimer coverage, create the appearance of gear chains. Density functional theory aids in identifying substrate stress associated with the chemisorption of PPN's acetylene group as the cause of this transition.

19.
Nano Lett ; 10(9): 3700-3, 2010 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-20681618

RESUMO

The diffusion and arrangements of CO adsorbates within nanometer-scale pores on a copper surface are investigated by low-temperature scanning tunneling microscopy. In contrast to extended terraces, confinement stabilizes dislocation lines that expose more than one-fourth of the adsorbate population to potentially more reactive adsorption configurations. Confinement allows correlation between adsorbate diffusivity and the number of adsorbates in the pore. A marked increase is found that coincides with the absence of dense films on the exposed facets. In combination, we find that in confinement CO molecules are much more likely to be at adsorption sites that allow lateral access, in contrast to the dense and uniform films on extended terraces.

20.
Environ Sci Pollut Res Int ; 28(4): 4262-4275, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32935215

RESUMO

L-Threonine and three kinds of conductive polymers were applied for anode modification in microbial fuel cells (MFCs) for decolorization of Congo red with simultaneous electricity generation. The description of modified anodes with FTIR, surface contact angle, and CV analysis showed that the anode surface was successfully grafted with functional groups, with improving wettability, as well as the increasing specific surface area and electrochemical activity. For L-threonine modification, the highest decolorization rate of 97% of the MFC, and meanwhile, the maximum current density of 155.8 mA/m2, was obtained at the modified concentration of 400 mg/L. For conductive polymer modifications, the poly (aniline-1,8-diaminonaphthalene) (short for PANDAN) owned the highest performance, with the current density 185 mA/m2, and the decolorization rate was 97%. Compared with L-threonine, the modifications by conductive polymers were more suitable for MFC decolorization due to their functional groups and unique conductivity. In addition, high-throughput sequencing analysis was conducted for the conductive polymers modified anodes to reveal their bioelectrochemical mechanisms.


Assuntos
Fontes de Energia Bioelétrica , Vermelho Congo , Eletricidade , Eletrodos , Características da Família , Polímeros , Treonina
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