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1.
Proc Natl Acad Sci U S A ; 120(5): e2208344120, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36689653

RESUMEN

Antibiotic resistance is an urgent threat to global health. Antidepressants are consumed in large quantities, with a similar pharmaceutical market share (4.8%) to antibiotics (5%). While antibiotics are acknowledged as the major driver of increasing antibiotic resistance, little attention is paid to the contribution of antidepressants in this process. Here, we demonstrate that antidepressants at clinically relevant concentrations induce resistance to multiple antibiotics, even following short periods of exposure. Antibiotic persistence was also enhanced. Phenotypic and genotypic analyses revealed the enhanced production of reactive oxygen species following exposure to antidepressants was directly associated with increased resistance. An enhanced stress signature response and stimulation of efflux pump expression were also associated with increased resistance and persistence. Mathematical modeling also predicted that antidepressants would accelerate the emergence of antibiotic-resistant bacteria, and persister cells would help to maintain the resistance. Overall, our findings highlight the antibiotic resistance risk caused by antidepressants.


Asunto(s)
Antibacterianos , Antidepresivos , Antibacterianos/farmacología , Mutación , Antidepresivos/farmacología , Farmacorresistencia Microbiana , Bacterias
2.
Environ Microbiol ; 24(11): 5261-5276, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36054646

RESUMEN

Antibiotic resistance is a global concern threatening public health. Horizontal gene transfer (HGT) between bacterial species contributes greatly to the dissemination of antibiotic resistance. Conjugation is one of the major HGT pathways responsible for the spread of antibiotic resistance genes (ARGs). Antidepressant drugs are commonly prescribed antipsychotics for major depressive disorders and are frequently detected in aquatic environments. However, little is known about how antidepressants stress bacteria and whether such effect can promote conjugation. Here, we report that commonly prescribed antidepressants, sertraline, duloxetine, fluoxetine, and bupropion, can promote the conjugative transfer of plasmid-borne multidrug resistance genes carried by environmentally and clinically relevant plasmids. Noteworthy, the transfer of plasmids across bacterial genera is significantly enhanced by antidepressants at clinically relevant concentrations. We also reveal the underlying mechanisms of enhanced conjugative transfer by employing flow cytometric analysis, genome-wide RNA sequencing and proteomic analysis. Antidepressants induce the production of reactive oxygen species and the SOS response, increase cell membrane permeability, and upregulate the expression of conjugation relevant genes. Given the contribution of HGT in the dissemination of ARGs, our findings highlight the importance of prudent prescription of antidepressants and to the potential connection between antidepressants and increasing antibiotic resistance.


Asunto(s)
Trastorno Depresivo Mayor , Proteómica , Humanos , Trastorno Depresivo Mayor/genética , Farmacorresistencia Microbiana/genética , Transferencia de Gen Horizontal , Plásmidos/genética , Antibacterianos/farmacología , Bacterias/genética , Antidepresivos/farmacología , Genes Bacterianos
3.
Environ Sci Technol ; 56(21): 15108-15119, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36251935

RESUMEN

Although triclosan, as a widely used antiseptic chemical, is known to promote the transmission of antibiotic resistance to diverse hosts in pure culture, it is still unclear whether and how triclosan could affect the transmission of broad-host-range plasmids among complex microbial communities. Here, bacterial culturing, fluorescence-based cell sorting, and high-throughput 16S rRNA gene amplicon sequencing were combined to investigate contributions of triclosan on the transfer rate and range of an IncP-type plasmid from a proteobacterial donor to an activated sludge microbiome. Our results demonstrate that triclosan significantly enhances the conjugative transfer of the RP4 plasmid among activated sludge communities at environmentally relevant concentrations. High-throughput 16S rRNA gene sequencing on sorted transconjugants demonstrates that triclosan not only promoted the intergenera transfer but also the intragenera transfer of the RP4 plasmid among activated sludge communities. Moreover, triclosan mediated the transfer of the RP4 plasmid to opportunistic human pathogens, for example, Legionella spp. The mechanism of triclosan-mediated conjugative transfer is primarily associated with excessive oxidative stress, followed by increased membrane permeability and provoked SOS response. Our findings offer insights into the impacts of triclosan on the dissemination of antibiotic resistance in the aquatic environmental microbiome.


Asunto(s)
Microbiota , Triclosán , Antibacterianos/farmacología , Conjugación Genética , Farmacorresistencia Microbiana/genética , Transferencia de Gen Horizontal , Genes Bacterianos , Plásmidos , ARN Ribosómico 16S/genética , Aguas del Alcantarillado/microbiología , Triclosán/farmacología
4.
Front Pharmacol ; 15: 1393693, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38855753

RESUMEN

Colorectal cancer is a common malignant tumor with high mortality, for which chemotherapy resistance is one of the main reasons. The high expression of ABCG2 in the cancer cells and expulsion of anticancer drugs directly cause multidrug resistance (MDR). Therefore, the development of new ABCG2 inhibitors that block the active causes of MDR may provide a strategy for the treatment of colorectal cancer. In this study, we find that dorsomorphin (also known as compound C or BML-275) potently inhibits the transporter activity of ABCG2, thereby preserving the chemotherapeutic agents mitoxantrone and doxorubicin to antagonize MDR in ABCG2-overexpressing colorectal cancer cells. Additionally, dorsomorphin does not alter ABCG2 protein expression. The results of molecular docking studies show that dorsomorphin is bound stably to the ABCG2-binding pocket, suggesting that dorsomorphin is a potent ABCG2 inhibitor that attenuates ABCG2-mediated MDR in colorectal cancer.

5.
Adv Mater ; : e2405404, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38804577

RESUMEN

Indoor photovoltaics (IPVs) are garnering increasing attention from both the academic and industrial communities due to the pressing demand of the ecosystem of Internet-of-Things. All-polymer solar cells (all-PSCs), emerging as a sub-type of organic photovoltaics, with the merits of great film-forming properties, remarkable morphological and light stability, hold great promise to simultaneously achieve high efficiency and long-term operation in IPV's application. However, the dearth of polymer acceptors with medium-bandgap has impeded the rapid development of indoor all-PSCs. Herein, a highly efficient medium-bandgap polymer acceptor (PYFO-V) is reported through the synergistic effects of side chain engineering and linkage modulation and applied for indoor all-PSCs operation. As a result, the PM6:PYFO-V-based indoor all-PSC yields the highest efficiency of 27.1% under LED light condition, marking the highest value for reported binary indoor all-PSCs to date. More importantly, the blade-coated devices using non-halogenated solvent (o-xylene) maintain an efficiency of over 23%, demonstrating the potential for industry-scale fabrication. This work not only highlights the importance of fine-tuning intramolecular charge transfer effect and intrachain coplanarity in developing high-performance medium-bandgap polymer acceptors but also provides a highly efficient strategy for indoor all-PSC application.

6.
Materials (Basel) ; 16(18)2023 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-37763600

RESUMEN

Tire-road characteristics are a critical focus of research in the automotive and transportation industries. On the one hand, the research can help optimize tires' structural design; on the other hand, it can analyze the mechanical response of the pavement structure under the vehicle load. In addition, the non-uniformity distribution of the tire ground stress will also have a direct impact on the skid resistance, which determines the driving safety. Due to the limitation of testing technology, the measurement of tire ground pressure was mainly carried out on a flat test platform, ignoring the roughness of the actual pavement surface texture. The tire-road contact characteristics research on the macro-texture and micro-texture of asphalt pavement needs to be broken through. A high-precision pressure-sensitive film measurement system is utilized to examine the actual contact characteristics between two types of automobile tires and three types of asphalt pavement in this paper. The influence law of pavement texture and patterned tires on the contact area and stress was explored, and the concentration effect of tire-road contact stress was evaluated. The results indicate that the contact area of grounding tires exhibits a nearly linear relationship with tire inflation pressure and load. Notably, the change in load has a more significant influence on the contact area than tire inflation pressure. On asphalt pavement, the contact reduction rate decreases by approximately 5-10% for block pattern tires and 10-15% for longitudinal pattern tires. Furthermore, as the texture depth of the pavement increases, the contact area between tires and the pavement texture decreases. The actual tire-road interface experiences significant stress concentration due to the embedding and meshing effects between the tire and road surface. Even on a flat steel surface, the peak stress at the edge of the tread block exceeds the 0.7 MPa design load, which is about 2.5-3 times higher than the design uniform load. The peak stress between the tire and asphalt pavement reaches 4-10 times the design uniform load, with a rising trend as the pavement texture depth increases. This study can provide relevant experimental technical support for tire design and functional design of asphalt pavement.

7.
Artículo en Inglés | MEDLINE | ID: mdl-37910808

RESUMEN

The multiple strategy design is crucial for enhancing the efficiency of nonprecious electrocatalysts in hydrogen evolution reaction (HER). In this work, we successfully synthesized N, P-codoped MoS2 nanosheets as highly efficient catalysts by integrating doping effects and phase engineering using a porous metal-organic framework (MOF) template. The electrocatalysts exhibit excellent bifunctional activity and stability in alkaline media. The N, P codoping induces electron redistribution to enhance conductivity and promote the intrinsic activity of the electrocatalysts. It optimizes the H* adsorption free energy and the dissociative adsorption energy, resulting in significant enhancement of HER activity. Moreover, the porous MOF structure exposes a large number of electrochemically active sites and facilitates the diffusion of ions and gases, which improve charge transfer efficiency and structural stability. Specifically, at a current density of 10 mA cm-2, the overpotential of the HER is only 32 mV, with a Tafel slope of 47 mV dec-1 and Faradaic efficiency as high as 98.51% (at 100 mA cm-2). Only a 338 mV overpotential is required to achieve a current density of 50 mA cm-2 for oxygen evolution reaction (OER), and a potential of 1.49 V (at 10 mA cm-2) is sufficient to drive overall water splitting. Further experimental measurements and first-principles calculations evidence that the exceptional performance is primarily attributed to the dual functionality of N and P dopants, which not only activate additional S sites but also initialize the phase transition of 2H to 1T-MoS2 to facilitate the rapid charge transfer. Through in-depth exploration of the combined design of multiple strategies for efficient catalysts, our work paves a new way for the development of future efficient nonprecious metal catalysts.

8.
Oncogene ; 42(14): 1101-1116, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36792757

RESUMEN

Although N4-acetylcytidine (ac4C) modification affects the stability and translation of mRNA, it is unknown whether it exists in noncoding RNAs, and its biological function is unclear. Here, nucleotide-resolution method for profiling CTC-490G23.2 ac4C sites and gain- and loss-of-function experiments revealed that N-acetyltransferase 10 (NAT10) is responsible for ac4C modification of long noncoding RNAs (lncRNAs). NAT10-mediated ac4C modification leads to the stabilization and overexpression of lncRNA CTC-490G23.2 in primary esophageal squamous cell carcinoma (ESCC) and its further upregulation in metastatic tissues. CTC-490G23.2 significantly promotes cancer invasion and metastasis in vitro and in vivo. Mechanistically, CTC-490G23.2 acts as a scaffold to increase the binding of CD44 pre-mRNA to polypyrimidine tract-binding protein 1 (PTBP1), resulting in a oncogenic splicing switch from the standard isoform CD44s to the variant isoform CD44v(8-10). CD44v(8-10), but not CD44s, binds to and increases the protein stability of vimentin. Expression levels of CTC-490G23.2 and CD44v(8-10) can predict poor prognosis in cancer patients. Furthermore, the antisense oligonucleotide (ASO)/SV40-LAH4-L1 peptide self-assembled nanocomplexes targeting CTC490G23.2 exerts a significantly suppressive effect on cancer metastasis. The outcome of this study will provide new mechanistic insight into the ac4C modification of lncRNAs and useful clues for the development of novel systemic therapies and prognostic biomarkers.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Empalme Alternativo , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago/genética , Isoformas de Proteínas/genética , Regulación Neoplásica de la Expresión Génica , Receptores de Hialuranos/genética , Receptores de Hialuranos/metabolismo , Ribonucleoproteínas Nucleares Heterogéneas/genética , Ribonucleoproteínas Nucleares Heterogéneas/metabolismo , Proteína de Unión al Tracto de Polipirimidina/genética , Proteína de Unión al Tracto de Polipirimidina/metabolismo
9.
ISME Commun ; 2(1): 63, 2022 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37938640

RESUMEN

The development of antibiotic resistance as an unavoidable consequence of the application of antimicrobials is a significant concern for human health. Antidepressants are being increasingly consumed globally. Human gut microbial communities are frequently exposed to antidepressants, yet little is known about the interaction between antidepressants and antibiotic resistance. This study aimed to investigate whether antidepressants can accelerate the dissemination of antibiotic resistance by increasing the rate of the horizontal transfer of antibiotic resistance genes (ARGs). Results demonstrated that some of the commonly-prescribed antidepressants (Duloxetine, Sertraline, Fluoxetine and Bupropion) at clinically relevant concentrations can significantly (n = 9; padj < 0.01) promote the transformation of extracellular ARGs into Acinetobacter baylyi ADP1 for a maximum of 2.3-fold, which is primarily associated with the overproduction of reactive oxygen species. The increased cell membrane permeability and porosity, stimulated transcription and translation of competence, SOS response, universal stress response and ATP synthesis-related genes are also associated with antidepressants-enhanced transformation. This study demonstrated that some antidepressants can speed up the spread of antibiotic resistance by promoting the transformation of ARGs, which emphasizes the necessity to assess the potential risks of antidepressants in spreading antibiotic resistance during clinical antidepressant applications.

10.
Microbiome ; 10(1): 124, 2022 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-35953866

RESUMEN

BACKGROUND: Horizontal gene transfer (HGT) plays a critical role in the spread of antibiotic resistance and the evolutionary shaping of bacterial communities. Conjugation is the most well characterized pathway for the spread of antibiotic resistance, compared to transformation and transduction. While antibiotics have been found to induce HGT, it remains unknown whether non-antibiotic pharmaceuticals can facilitate conjugation at a microbial community-wide level. RESULTS: In this study, we demonstrate that several commonly consumed non-antibiotic pharmaceuticals (including carbamazepine, ibuprofen, naproxen and propranolol), at environmentally relevant concentrations (0.5 mg/L), can promote the conjugative transfer of IncP1-α plasmid-borne antibiotic resistance across entire microbial communities. The over-generation of reactive oxygen species in response to these non-antibiotic pharmaceuticals may contribute to the enhanced conjugation ratios. Cell sorting and 16S rRNA gene amplicon sequencing analyses indicated that non-antibiotic pharmaceuticals modulate transconjugant microbial communities at both phylum and genus levels. Moreover, microbial uptake ability of the IncP1-α plasmid was also upregulated under non-antibiotic pharmaceutical exposure. Several opportunistic pathogens, such as Acinetobacter and Legionella, were more likely to acquire the plasmid conferring multidrug resistance. CONCLUSIONS: Considering the high possibility of co-occurrence of pathogenic bacteria, conjugative IncP1-α plasmids and non-antibiotic pharmaceuticals in various environments (e.g., activated sludge systems), our findings illustrate the potential risk associated with increased dissemination of antibiotic resistance promoted by non-antibiotic pharmaceuticals in complex environmental settings. Video abstract.


Asunto(s)
Antibacterianos , Transferencia de Gen Horizontal , Antibacterianos/farmacología , Bacterias/genética , Preparaciones Farmacéuticas , Plásmidos/genética , ARN Ribosómico 16S
11.
ISME J ; 14(8): 2179-2196, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32424247

RESUMEN

Antibiotic resistance is a serious global threat for public health. Considering the high abundance of cell-free DNA encoding antibiotic resistance genes (ARGs) in both clinical and environmental settings, natural transformation is an important horizontal gene transfer pathway to transmit antibiotic resistance. It is acknowledged that antibiotics are key drivers for disseminating antibiotic resistance, yet the contributions of non-antibiotic pharmaceuticals on transformation of ARGs are overlooked. In this study, we report that some commonly consumed non-antibiotic pharmaceuticals, at clinically and environmentally relevant concentrations, significantly facilitated the spread of antibiotic resistance through the uptake of exogenous ARGs. This included nonsteroidal anti-inflammatories, ibuprofen, naproxen, diclofenac, the lipid-lowering drug, gemfibrozil, and the ß-blocker propranolol. Based on the results of flow cytometry, whole-genome RNA sequencing and proteomic analysis, the enhanced transformation of ARGs was affiliated with promoted bacterial competence, enhanced stress levels, over-produced reactive oxygen species and increased cell membrane permeability. In addition, a mathematical model was proposed and calibrated to predict the dynamics of transformation during exposure to non-antibiotic pharmaceuticals. Given the high consumption of non-antibiotic pharmaceuticals, these findings reveal new concerns regarding antibiotic resistance dissemination exacerbated by non-antibiotic pharmaceuticals.


Asunto(s)
Antibacterianos , Preparaciones Farmacéuticas , Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Farmacorresistencia Microbiana , Genes Bacterianos , Proteómica , Transformación Bacteriana
13.
J Innate Immun ; 7(2): 165-76, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25277143

RESUMEN

Bacterial infection often follows virus infection due to pulmonary interferon-γ (IFN-γ) production during virus infection, which down-regulates macrophage phagocytosis. The molecular mechanisms for this process are still poorly understood. In the present study, IFN-γ treatment significantly inhibited the ability of mouse macrophages to phagocytize nonopsonized chicken red blood cells (cRBCs), bacteria and beads in vitro, while it enhanced IgG- and complement-opsonized phagocytosis. IFN-γ treatment decreased the expression of MARCO (macrophage receptor with collagenous structure) in macrophages. Macrophages showed lower binding to and phagocytic ability of cRBCs when MARCO was blocked with antibody. In addition, IFN-γ induced high activity of mTOR (mammalian target of rapamycin) and decreased the expression of c/EBPß (CCAAT enhancer-binding protein ß) in macrophages. Rapamycin, a specific mTOR inhibitor, significantly reversed the inhibitory effect of IFN-γ on nonopsonized phagocytosis of macrophages and restored c/EBPß and MARCO expression. Biochemical assays showed that c/EBPß directly bound to the MARCO gene promoter. Rapamycin significantly hampered the viral-bacterial synergy and protected influenza-infected mice from subsequent bacterial infection. Thus, IFN-γ inhibited the nonopsonized phagocytosis of macrophages through the mTOR-c/EBPß-MARCO pathway. The present study offered evidence indicating that mTOR may be one of the key target molecules for the prevention of secondary bacterial infection caused by primary virus infection.


Asunto(s)
Virus de la Influenza A/inmunología , Interferón gamma/metabolismo , Macrófagos/inmunología , Infecciones por Orthomyxoviridae/metabolismo , Animales , Anticuerpos Bloqueadores/farmacología , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Embrión de Pollo , Pollos , Perros , Eritrocitos/inmunología , Células de Riñón Canino Madin Darby , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones , Ratones Endogámicos C57BL , Complejos Multiproteicos/metabolismo , Fagocitosis , Receptores Inmunológicos/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo
14.
Sci Rep ; 5: 14871, 2015 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-26445893

RESUMEN

Thymic epithelial cells (TECs) form a 3-dimentional network supporting thymocyte development and maturation. Besides epithelium and thymocytes, heterogeneous fibroblasts are essential components in maintaining thymic microenvironments. However, thymic fibroblast characteristics, development and function remain to be determined. We herein found that thymic non-hematopoietic CD45(-)FSP1(+) cells represent a unique Fibroblast specific protein 1 (FSP1)(-)fibroblast-derived cell subset. Deletion of these cells in FSP1-TK transgenic mice caused thymus atrophy due to the loss of TECs, especially mature medullary TECs (MHCII(high), CD80(+) and Aire(+)). In a cyclophosphamide-induced thymus injury and regeneration model, lack of non-hematopoietic CD45(-)FSP1(+) fibroblast subpopulation significantly delayed thymus regeneration. In fact, thymic FSP1(+) fibroblasts released more IL-6, FGF7 and FSP1 in the culture medium than their FSP1(-) counterparts. Further experiments showed that the FSP1 protein could directly enhance the proliferation and maturation of TECs in the in vitro culture systems. FSP1 knockout mice had significantly smaller thymus size and less TECs than their control. Collectively, our studies reveal that thymic CD45(-)FSP1(+) cells are a subpopulation of fibroblasts, which is crucial for the maintenance and regeneration of TECs especially medullary TECs through providing IL-6, FGF7 and FSP1.


Asunto(s)
Células Epiteliales/citología , Fibroblastos/citología , Regeneración/fisiología , Proteínas S100/genética , Timo/citología , Animales , Animales Recién Nacidos , Comunicación Celular/fisiología , Diferenciación Celular , Proliferación Celular , Ciclofosfamida/farmacología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Femenino , Feto , Factor 7 de Crecimiento de Fibroblastos/genética , Factor 7 de Crecimiento de Fibroblastos/metabolismo , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Expresión Génica , Interleucina-6/genética , Interleucina-6/metabolismo , Antígenos Comunes de Leucocito/genética , Antígenos Comunes de Leucocito/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Transgénicos , Técnicas de Cultivo de Órganos , Proteína de Unión al Calcio S100A4 , Proteínas S100/deficiencia , Timo/efectos de los fármacos , Timo/metabolismo
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