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1.
NPJ Precis Oncol ; 8(1): 139, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38956432

RESUMEN

Immunotherapy exhibited potential effects for advanced hepatocellular carcinoma, unfortunately, the clinical benefits are often countered by cancer adaptive immune suppressive response. Uncovering the mechanism how cancer cells evade immune surveillance would help to develop new immunotherapy approaches and combination therapy. In this article, by analyzing the transcriptional factors which modulate the differentially expressed genes between T cell infiltration high group and low group, we identified oncoprotein B cell lymphoma 6 (BCL6) suppresses the infiltration and activation of tumor infiltrating T lymphocytes, thus correlated with poorer clinical outcome. By using antibody deletion experiment, we further demonstrated that CD4+T cells but not CD8+T cells are the main lymphocyte population suppressed by Bcl6 to promote HCC development. Mechanistically, BCL6 decreases cancer cell expression of pro-inflammatory cytokines and T lymphocyte chemokines such as IL6, IL1F6, and CCL5. Moreover, BCL6 upregulates Endothelial cell-specific molecule 1 (ESM1) to inhibit T lymphocyte recruitment and activation possibly through ICAM-1/LFA-1 signaling pathway. Our findings uncovered an unappreciated paracrine mechanism how cancer cell-derived BCL6 assists cancer cell immune evasion, and highlighted the role of CD4+T cells in HCC immune surveillance.

2.
Cardiovasc Res ; 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850163

RESUMEN

AIMS: The widespread use of immune checkpoint inhibitors (ICIs) has demonstrated significant survival benefits for cancer patients and also carry the risk of immune-related adverse events (irAEs). ICIs-associated myocarditis is a rare and serious adverse event with a high mortality rate. Here, we explored the mechanism underlying ICIs-associated myocarditis. METHODS AND RESULTS: Using the peripheral blood of patients with ICIs therapy and ICIs treated mice with transplanted tumors, we dissect the immune cell subsets and inflammatory factors associated with myocarditis. Compared to the control group, patients with myocarditis after ICIs therapy showed an increase in NK cells and myeloid cells in peripheral blood, while T cells significantly decreased. Among T cells, there was an imbalance of CD4/CD8 ratio in the peripheral blood of myocarditis patients, with a significant decrease in central memory CD4+ T (CD4+ TCM) cells. RNA-Seq revealed that CD4+ TCM cells in myocarditis patients were an immunosuppressive cell subset, which highly express the immunosuppressive factor IL4I1. To elucidate the potential mechanism of the decrease in CD4+ TCM cells, protein array was performed and revealed that several inflammatory factors gradually increased with the severity of myocarditis in the myocarditis group, such as IL-1B/CXCL13/CXCL9, while the myocardial protective factor IL-15 decreased. Correlation analysis indicated a positive correlation between IL-15 and CD4+ TCM cells, with high expression of IL-15 receptor IL15RA. Furthermore, in vivo studies using an anti-PDL1 antibody in a mouse tumor model indicated a reduction in CD4+ TCM cells and an increase in CD8+ TEMRA cells, alongside evidence of cardiac fibrosis. Conversely, combining anti-PDL1 antibody treatment with IL-15 led to a resurgence of CD4+ TCM cells, a reduction in CD8+ TEMRA cells, and a mitigated risk of cardiac fibrosis. CONCLUSIONS: Our data highlight CD4+ TCM cells as a crucial role in cardiac protection during ICIs therapy. IL-15, IL4I1 and CD4+ TCM cells can serve as therapeutic targets to reduce ICIs-associated myocarditis in cancer patients.

3.
Macromol Rapid Commun ; : e2400246, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38923160

RESUMEN

A novel bromothiophene-functionalized BF2-curcuminoid (BTC-BF2) is synthesized by Knoevenagel condensation reaction. The structure of BTC-BF2 is determined by 1H-nuclear magnetic resonance (1H NMR), 13C-nuclear magnetic resonance (13C NMR), and high-resolution mass spectrometry (HRMS). Moreover, a nearly coplanar single crystal structure is successfully obtained and form a mesh structure through intermolecular multiple C─H···F hydrogen bond interactions. As expected, as-prepared BTC-BF2 exhibits solvent-dependent photophysical properties in solvents with different polarity and an intense red solid-state fluorescence. Density functional theory calculations further verify the relationships between its intrinsic electronic features and the photophysical properties. For its potential application aspect, BTC-BF2 shows a certain ability to generate singlet oxygen under irradiation with 530 nm green light. Moreover, BTC-BF2 can be utilized as versatile building block to construct novel far-red or NIR BF2-curcuminoid complexes for widely biological applications.

4.
J Virol ; 98(4): e0184423, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38436247

RESUMEN

Porcine Mx1 is a type of interferon-induced GTPase that inhibits the replication of certain RNA viruses. However, the antiviral effects and the underlying mechanism of porcine Mx1 for porcine reproductive and respiratory syndrome virus (PRRSV) remain unknown. In this study, we demonstrated that porcine Mx1 could significantly inhibit PRRSV replication in MARC-145 cells. By Mx1 segment analysis, it was indicated that the GTPase domain (68-341aa) was the functional area to inhibit PRRSV replication and that Mx1 interacted with the PRRSV-N protein through the GTPase domain (68-341aa) in the cytoplasm. Amino acid residues K295 and K299 in the G domain of Mx1 were the key sites for Mx1-N interaction while mutant proteins Mx1(K295A) and Mx1(K299A) still partially inhibited PRRSV replication. Furthermore, we found that the GTPase activity of Mx1 was dominant for Mx1 to inhibit PRRSV replication but was not essential for Mx1-N interaction. Finally, mechanistic studies demonstrated that the GTPase activity of Mx1 played a dominant role in inhibiting the N-Nsp9 interaction and that the interaction between Mx1 and N partially inhibited the N-Nsp9 interaction. We propose that the complete anti-PRRSV mechanism of porcine Mx1 contains a two-step process: Mx1 binds to the PRRSV-N protein and subsequently disrupts the N-Nsp9 interaction by a process requiring the GTPase activity of Mx1. Taken together, the results of our experiments describe for the first time a novel mechanism by which porcine Mx1 evolves to inhibit PRRSV replication. IMPORTANCE: Mx1 protein is a key mediator of the interferon-induced antiviral response against a wide range of viruses. How porcine Mx1 affects the replication of porcine reproductive and respiratory syndrome virus (PRRSV) and its biological function has not been studied. Here, we show that Mx1 protein inhibits PRRSV replication by interfering with N-Nsp9 interaction. Furthermore, the GTPase activity of porcine Mx1 plays a dominant role and the Mx1-N interaction plays an assistant role in this interference process. This study uncovers a novel mechanism evolved by porcine Mx1 to exert anti-PRRSV activities.


Asunto(s)
Proteínas de Resistencia a Mixovirus , Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Proteínas no Estructurales Virales , Replicación Viral , Animales , Línea Celular , Interferones/inmunología , Interferones/metabolismo , Mutación , Proteínas de Resistencia a Mixovirus/química , Proteínas de Resistencia a Mixovirus/genética , Proteínas de Resistencia a Mixovirus/metabolismo , Síndrome Respiratorio y de la Reproducción Porcina/enzimología , Síndrome Respiratorio y de la Reproducción Porcina/metabolismo , Síndrome Respiratorio y de la Reproducción Porcina/virología , Virus del Síndrome Respiratorio y Reproductivo Porcino/crecimiento & desarrollo , Virus del Síndrome Respiratorio y Reproductivo Porcino/metabolismo , Unión Proteica , Porcinos/virología , Proteínas no Estructurales Virales/antagonistas & inhibidores , Proteínas no Estructurales Virales/metabolismo
5.
Nat Commun ; 15(1): 2689, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38538612

RESUMEN

The applications of silica-based glass have evolved alongside human civilization for thousands of years. High-precision manufacturing of three-dimensional (3D) fused silica glass objects is required in various industries, ranging from everyday life to cutting-edge fields. Advanced 3D printing technologies have emerged as a potent tool for fabricating arbitrary glass objects with ultimate freedom and precision. Stereolithography and femtosecond laser direct writing respectively achieved their resolutions of ~50 µm and ~100 nm. However, fabricating glass structures with centimeter dimensions and sub-micron features remains challenging. Presented here, our study effectively bridges the gap through engineering suitable materials and utilizing one-photon micro-stereolithography (OµSL)-based 3D printing, which flexibly creates transparent and high-performance fused silica glass components with complex, 3D sub-micron architectures. Comprehensive characterizations confirm that the final material is stoichiometrically pure silica with high quality, defect-free morphology, and excellent optical properties. Homogeneous volumetric shrinkage further facilitates the smallest voxel, reducing the size from 2.0 × 2.0 × 1.0 µm3 to 0.8 × 0.8 × 0.5 µm3. This approach can be used to produce fused silica glass components with various 3D geometries featuring sub-micron details and millimetric dimensions. This showcases promising prospects in diverse fields, including micro-optics, microfluidics, mechanical metamaterials, and engineered surfaces.

6.
Micromachines (Basel) ; 15(1)2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38258228

RESUMEN

Hollow microspheres as the filler material of syntactic foams have been adopted in extensive practical applications, where the physical parameters and their homogeneity have been proven to be critical factors during the design process, especially for high-specification scenarios. Based on double-emulsion droplet templates, hollow microspheres derived from microfluidics-enabled soft manufacturing have been validated to possess well-controlled morphology and composition with a much narrower size distribution and fewer defects compared to traditional production methods. However, for more stringent requirements, the innate density difference between the core-shell solution of the double-emulsion droplet template shall result in the wall thickness heterogeneity of the hollow microsphere, which will lead to unfavorable mechanical performance deviations. To clarify the specific mechanical response of microfluidics-derived hollow silica microspheres with varying eccentricities, a hybrid method combining experimental nanoindentation and a finite element method (FEM) simulation was proposed. The difference in eccentricity can determine the specific mechanical response of hollow microspheres during nanoindentation, including crack initiation and the evolution process, detailed fracture modes, load-bearing capacity, and energy dissipation capability, which should shed light on the necessity of optimizing the concentricity of double-emulsion droplets to improve the wall thickness homogeneity of hollow microspheres for better mechanical performance.

7.
Vet Microbiol ; 288: 109923, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38061277

RESUMEN

Escherichia coli and Salmonella Typhimurium are the main pathogens of diarrhea in weaned piglets. The prevention of bacterial diarrhea in weaned piglets by phage is rarely reported. We conducted this study to evaluate the preventive effect of phages on mixed Escherichia coli and Salmonella Typhimurium infections in weaned piglets. A novel phage named NJ12 was isolated by using Salmonella Typhimurium SM022 as host bacteria and characterized by electron microscopy, genomic analysis and in vitro bacteriostatic activity. Phage NJ12 and a previously reported phage EP01 were microencapsulated with sodium alginate to make phage cocktail. Microencapsulated phage cocktail and PBS (Phosphate buffer solution) were used to piglets the phage and phage-free group through oral administration before bacterial infection 2 h, respectively. Piglets of the phage and phage-free group were consumed with feed contaminated with 6 mL (108CFU/mL) Escherichia coli O157:H7 GN07 (GXEC-N07) and 6 mL (108CFU/mL) SM022 every day for seven consecutive days. The results showed that piglets in the phage-free group had more severe diarrhea, larger decreased average weight gain and higher levels of neutrophils compared with piglets in phage group. Meanwhile, piglets in the phage-free group had higher load of SM022 and GN07 in jejunal tissue and more severe intestinal damage compared with piglets in group phage in vivo. In addition, oral administration phage can significant decreased the relative abundance of Enterobacteriaceae but hardly repaired the changes of diversity and composition of gut microbiota caused by the mixed infection of SM022 and GN07. This implies that phage used as a feed additive have a marvelous preventive effect on bacterial diarrhea during weaning of piglets.


Asunto(s)
Bacteriófagos , Disentería , Infecciones por Escherichia coli , Escherichia coli O157 , Infecciones por Salmonella , Enfermedades de los Porcinos , Animales , Porcinos , Salmonella typhimurium , Escherichia coli O157/genética , Destete , Diarrea/prevención & control , Diarrea/veterinaria , Diarrea/microbiología , Infecciones por Escherichia coli/prevención & control , Infecciones por Escherichia coli/veterinaria , Infecciones por Escherichia coli/microbiología , Disentería/veterinaria , Enfermedades de los Porcinos/prevención & control , Enfermedades de los Porcinos/microbiología
8.
Complement Ther Med ; 79: 103006, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37972694

RESUMEN

OBJECTIVE: This study aimed to employ bibliometric approaches to assess the worldwide scientific achievements in acupuncture for facial paralysis research from 2013 to 2023, and explore the hotspots and frontiers. METHODS: Articles related to acupuncture facial paralysis were retrieved from the Web of Science Core Collection (WoSCC). CiteSpace was utilized to examine journals, publication year, country, institution, cited authors, as well as authors.Research hotspots and trends were analyzed by mapping co-citation networks and keywords. RESULTS: The period from January 1, 2013, to July 31, 2023, yielded nearly 145 research records on acupuncture treatment for facial paralysis, with a steady increase in the number of annual publications.In terms of the number of publications, OTOLARYNGOLOGY HEAD NECK had the highest publication count, while AM J CHINESE MED exhibited the highest centrality and citation frequency among the cited journals. Further, 54.4 % of publications originated from China, followed by USA (8.2 %) and Germany (8.2 %). Guangzhou University of Chinese Medicine stood out with the highest publication volume among institutions. Guntinas-lichius, Orlando was the most prolific author, and PEITERSEN E was the most cited author. The keywords "Randomized controlled trials" and "multicenter" displayed high frequency and centrality, indicating that clinical trials with a randomized controlled design and multicenter studies were prevalent research methods, likely to remain a future trend. CONCLUSION: Acupuncture's potential in the treatment of facial paralysis merits further research. Authors from different countries/regions and organizations need to eliminate language and academic barriers and strengthen collaboration and communication. Current research hotspots focus on "brain", "nerve", "electrical stimulation", "RCT" and "guidelines". The study of acupuncture mechanisms, especially based on the central nervous system mechanism, may be the future research hotspot.


Asunto(s)
Terapia por Acupuntura , Parálisis Facial , Humanos , Parálisis Facial/terapia , Pueblo Asiatico , Bibliometría , Encéfalo
9.
Neuropsychiatr Dis Treat ; 19: 2381-2400, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37954034

RESUMEN

Objective: To systematically evaluate the efficacy of acupuncture in the treatment of schizophrenia. Methods: We searched China National Knowledge Infrastructure (CNKI), Wanfang Database, Chongqing VIP Chinese Science and Technology Periodical Database (VIP), China Biology Medicine Database (CBM), PubMed, Embase, Web of Science, Cochrane Library for relevant literature on the acupuncture treatment of schizophrenia published from database inception to May 17, 2023. The evaluation criteria included total effective rate, incidence of adverse reactions, TESS scale, PANSS scale, BPRS scale, SANA scale, SAPS scale. Two researchers independently screened the literature, extracted data, and assessed the risk of bias of the included studies. The RevMan 5.4 software was used for meta-analysis, risk of bias (ROB) evaluation tool was used to evaluate the risk of bias of the studies, and the GRADE evaluation tool was used to evaluate the quality of evidence. The study was registered on PROSPERO, CRD42023416438. Results: A total of 38 RCTs involving 3143 patients were included in the meta-analysis. The results showed that acupuncture can improve the total effective rate [OR=3.43 (95% CI: 2.71, 4.35), moderate credibility], reduce the incidence of adverse reactions [OR=0.45 (95% CI: 0.32, 0.63), moderate credibility], reduce the TESS score (side effect scale) [MD=-1.83 (95% CI: -2.94, -0.71), very low credibility]. Acupuncture also reduced the PANSS total score [MD=-5.75 (95% CI: -8.08, -3.42), very low credibility], SANA score [MD=-2.66 (95% CI: -6.84, 1.51), very low credibility], SAPS score [MD=-1.26 (95% CI: -2.55, -0.02), very low credibility], and BPRS score [MD=-7.02 (95% CI: -10.59, -3.46), very low credibility]. Conclusion: Existing evidence indicates that acupuncture as an adjunctive therapy can improve the total effective rate of SZ patients, reduce the incidence of adverse reactions, improve clinical symptoms, and alleviate depression and anxiety in SZ patients. However, more high-quality clinical research evidence is still needed to support these findings.

10.
BMC Vet Res ; 19(1): 165, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37730566

RESUMEN

BACKGROUND: Escherichia coli (E. coli) is a common pathogen that often causes diarrhea in piglets. Since bacteria are becoming more and more resistant to antibiotics, phages have become a promising alternative therapy. However, the therapy of oral phage often fails to achieve the desired effect. A novel phage named A221 was isolated by using E. coli GXXW-1103 as host strain, characterized by electron microscopy, genomic sequencing and analyzed by measuring lysis ability in vitro. RESULTS: Phage A221 was identified as a member of Ackermannviridae, Aglimvirinae, Agtrevirus with 153297 bp genome and effectively inhibited bacterial growth in vitro for 16 h. This study was conducted to evaluate the therapeutic effect of oral microencapsulated phage A221 on E. coli GXXW-1103 infections in weaned piglets. The protective effect of phage was evaluated by body weight analysis, bacterial load and histopathological changes. The results showed that with the treatment of phage A221, the body weight of piglets increased, the percentage of Enterobacteriaceae in duodenum decreased to 0.64%, the lesions in cecum and duodenum were alleviated, and the bacterial load in the jejunal lymph nodes, cecum and spleen were also significantly different with infected group (P < 0.001). CONCLUSIONS: The results showed that phage A221 significantly increased the daily weight gain of piglets, reduced the bacterial load of tissues and the intestinal lesions, achieved the same therapeutic effect as antibiotic Florfenicol. Taken together, oral microencapsulated phage A221 has a good therapeutic effect on bacterial diarrhea of weaned piglets, which provides guidance for the clinical application of phage therapy in the future.


Asunto(s)
Bacteriófagos , Infecciones por Escherichia coli , Terapia de Fagos , Enfermedades de los Porcinos , Animales , Porcinos , Escherichia coli , Terapia de Fagos/veterinaria , Infecciones por Escherichia coli/terapia , Infecciones por Escherichia coli/veterinaria , Diarrea/terapia , Diarrea/veterinaria , Antibacterianos/uso terapéutico , Peso Corporal , Enfermedades de los Porcinos/terapia
11.
ACS Appl Mater Interfaces ; 15(32): 38485-38495, 2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37539469

RESUMEN

To improve the ionic conductivity and cycling stability of solid-state lithium batteries based on poly(ethylene oxide) (PEO) electrolytes, we developed a sandwich-structured composite polymer electrolyte (sandwich-CPE) PEO-TiN/PEO-LiYF4/PEO-TiN. The sandwich-CPE delivers a high ionic conductivity of 1.7 × 10-4 S cm-1 at 30 °C and a wide potential window of 0 to 5.0 V (vs Li/Li+). Adding PEO-TiN leads to the formation of Li3N between Li and sandwich-CPE during cycling, which effectively reduces the level of Li dendrite formation. Additionally, PEO-TiN acts as a sacrificial layer to stop the entry of Li dendrites into the interlayer PEO-LiYF4. Using the sandwich-CPE, LiFePO4 retains a reversible capacity of 113.8 mA h g-1 at 30 °C after 300 cycles under 0.5 C. For high-voltage cells, LiNi0.5Co0.2Mn0.3O2 retains a capacity retention of 71.4% at 45 °C after 300 cycles under 0.2 C among 3.0-4.3 V, while Li3V2(PO4)3 delivers an initial discharge capacity of 108.1 mA h g-1 at 60 °C and retains 81.6% after 500 cycles under 1 C among 2.8-4.4 V. These results demonstrate the strong electrochemical compatibility of the sandwich-CPE, enabling high reversible capacity and good cycling stability for solid-state Li batteries with different cathodes at different temperatures and current rates.

12.
Virus Genes ; 59(4): 613-623, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37170002

RESUMEN

As the problem of bacterial resistance becomes serious day by day, bacteriophage as a potential antibiotic substitute attracts more and more researchers' interest. In this study, Escherichia phage Kayfunavirus CY1 was isolated from sewage samples of swine farms and identified by biological characteristics and genomic analysis. One-step growth curve showed that the latent period of phage CY1 was about 10 min, the outbreak period was about 40 min and the burst size was 35 PFU/cell. Analysis of the electron microscopy and whole-genome sequence showed that the phage should be classified as a member of the Autographiviridae family, Studiervirinae subfamily. Genomic analysis of phage CY1 (GenBank accession no. OM937123) revealed a genome size of 39,173 bp with an average GC content of 50.51% and 46 coding domain sequences (CDSs). Eight CDSs encoding proteins involved in the replication and regulation of phage DNA, 2 CDSs encoded lysis proteins, 14 CDSs encoded packing and morphogenesis proteins. Genomic and proteomic analysis identified no sequence that encoded for virulence factor, integration-related proteins or antibiotic resistance genes. In summary, morphological and genomics suggest that phage CY1 is more likely a novel Escherichia phage.


Asunto(s)
Bacteriófagos , Caudovirales , Porcinos , Animales , Proteómica , Genoma Viral/genética , Genómica , Bacteriófagos/genética , Caudovirales/genética , Escherichia/genética
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 294: 122488, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-36822121

RESUMEN

Exploring novel dithienylethenes (DTEs) with efficient photochromism has drawn increasing attention in virtue of the potential applications for photoelectric functional materials. In this contribution, we presented two novel acceptor-acceptor (A-A) type DTE derivatives (4a and 4b) by incorporating the diestervinyl moieties with strong electron-withdrawing capacity into two sides of DTE skeleton. The corresponding structures were well confirmed by the NMR (1H and 13C) and HRMS. When irradiated alternately with ultraviolet and visible light, 4a and 4b showed efficient photochromism in toluene, chloroform and DMSO, clearly implying a solvent-dependence feature. Moreover, excellent photoswitching behaviors were also observed in the poly(methyl methacrylate) (PMMA) film. The density functional theory (DFT) calculations suggested that strong Acceptor-Acceptor effect plays a dominative role in the efficient photochromic performance. Hence, this study will provide a useful guidance for developing high-performance DTE derivatives in multi-media.

14.
ACS Appl Mater Interfaces ; 15(12): 15928-15937, 2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-36795543

RESUMEN

In metal metallurgy, precipitation strengthening is widely used to increase material strength by utilizing the impediment effect of the second-phase particles on dislocation movements. Inspired by this mechanism, in this paper, novel multiphase heterogeneous lattice materials are developed with enhanced mechanical properties utilizing a similar hindering effect of second-phase lattice cells on the shear band propagation. For this purpose, biphase and triphase lattice samples are fabricated using high-speed multi jet fusion (MJF) and digital light processing (DLP) additive manufacturing techniques, and a parametric study is carried out to investigate their mechanical properties. Different from the conventional random distribution, the second-phase and third-phase cells in this work are continuously distributed along the regular pattern of a larger-scale lattice to form internal hierarchical lattice structures. The results show that the triphase lattices possess balanced mechanical properties. Interestingly, this indicates that introducing a relatively weak phase also has the potential to improve the stiffness and plateau stress, which is distinct from the common mixed rule. This work is aimed at providing new references for the heterogeneous lattice design with outstanding mechanical properties through material microstructure inspiration.

15.
Virus Genes ; 59(2): 302-311, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36701048

RESUMEN

Escherichia coli is a common conditional pathogen, for which antibiotic therapy is considered an effective treatment. The imprudent use of antibiotics has led to the increase of multiple-antibiotic-resistant E. coli species. With the incidence of antibiotic resistance reaching a crisis point, it is imperative to find alternative treatments for multidrug-resistant infections. Using phage for pathogen control is a promising treatment option to combat bacterial resistance. In this study, a novel virulent Podoviridae phage Kayfunavirus TM1 infecting Escherichia coli was isolated from pig farm sewage in Guangxi, China. The one-step growth curve with the optimal multiplicity of infection of 0.01 revealed a latent period of 10 min and a burst size of 50 plaque-forming units per cell. The stability test reveals that it is stable from 4 to 60 °C and pH from 3 to 11. The double-stranded DNA genome of phage Kayfunavirus TM1 is composed of 39,948 base pairs with a GC content of 50.03%.


Asunto(s)
Bacteriófagos , Porcinos , Animales , Bacteriófagos/genética , Escherichia coli/genética , Genoma Viral , ADN Viral/genética , China , Antibacterianos
16.
Bioelectrochemistry ; 150: 108345, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36495704

RESUMEN

Escherichia coli (E. coli) O157:H7 is one of the most important foodborne pathogens that causing severe foodborne diseases. With the development of foodborne diseases, there is an urgent need to seek new methods for early detection and monitoring of E. coli O157:H7. In this study, an electrochemical biosensor using phage EP01 as the recognition agent for detection of E. coli O157:H7 GXEC-N07 was established due to the specificity and high efficiency of phage EP01 in recognizing GXEC-N07. The biosensor was developed by depositing phages conjugated carboxyl graphene oxide (CFGO) and conductive carbon black (CB) onto the surface of glass carbon electrodes (GCEs). When detecting GXEC-N07 in the concentration range of 102 âˆ¼ 107 CFU/mL, the biosensor showed good linearity with a low detection limit of 11.8 CFU/mL, and the whole progress was in less than 30 min. The biosensor was successfully applied to the quantitative detection of GXEC-N07 in fresh milk and raw pork. The recovery values ranged from 60.8 % to 114.2 %. The biosensor provides a rapid, specific, low cost, and label free tool for E. coli O157:H7 GXEC-N07 detection. It is expected to become a powerful method for the detection of bacteria that threatening food safety and public health security.


Asunto(s)
Bacteriófagos , Técnicas Biosensibles , Escherichia coli O157 , Enfermedades Transmitidas por los Alimentos , Humanos , Contaminación de Alimentos/análisis , Microbiología de Alimentos , Técnicas Biosensibles/métodos , Enfermedades Transmitidas por los Alimentos/microbiología
17.
Viruses ; 14(12)2022 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-36560651

RESUMEN

Food contamination by Salmonella can lead to serious foodborne diseases that constantly threaten public health. Innovative and effective strategies are needed to control foodborne pathogenic contamination since the incidence of foodborne diseases has increased gradually. In the present study, two broad-spectrum phages named Salmonella phage PSE-D1 and Salmonella phage PST-H1 were isolated from sewage in China. Phages PSE-D1 and PST-H1 were obtained by enrichment with Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) CVCC1806 and Salmonella enterica subsp. enterica serovar Typhimurium (S. Typhimurium) CVCC3384, respectively. They were able to lyse Salmonella, E. coli and K. pneumoniae and exhibited broad host range. Further study demonstrated that PSE-D1 and PST-H1 showed high pH and thermal tolerances. Phage PSE-D1 belongs to the Jiaodavirus genus, Tevenvirinae subfamily, while phage PST-H1 belongs to the Jerseyvirus genus, Guernseyvirinae subfamily according to morphology and phylogeny. The results of genome analysis showed that PSE-D1 and PST-H1 lack virulence and drug-resistance genes. The effects of PSE-D1 and PST-H1 on controlling S. Enteritidis CVCC1806 and S. Typhimurium CVCC3384 contamination in three kinds of foods (eggshells, sausages and milk) were further investigated, respectively. Our results showed that, compared to phage-free groups, PSE-D1 and PST-H1 inhibited the growth of their host strain significantly. A significant reduction of host bacteria titers (1.5 and 1.9 log10 CFU/sample, p < 0.001) on eggshells was observed under PSE-D1 and PST-H1 treatments, respectively. Furthermore, administration of PSE-D1 and PST-H1 decreased the counts of bacteria by 1.1 and 1.2 log10 CFU/cm2 (p < 0.001) in sausages as well as 1.5 and 1.8 log10 CFU/mL (p < 0.001) in milk, respectively. Interesting, the bacteriostasis efficacy of both phages exhibited more significantly at 4 °C than that at 28 °C in eggshells and milk and sausages. In sum, the purpose of our research was evaluating the counteracting effect of phage PSE-D1 and PST-H1 on the spread of Salmonella on contaminated foods products. Our results suggested that these two phage-based biocontrol treatments are promising strategies for controlling pathogenic Salmonella contaminated food.


Asunto(s)
Enfermedades Transmitidas por los Alimentos , Fagos de Salmonella , Humanos , Escherichia coli , Microbiología de Alimentos , Salmonella enteritidis , Salmonella typhimurium
18.
Sci Rep ; 12(1): 20612, 2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36446864

RESUMEN

Facing the untrusted threats of network elements and PKI/CA faced by SR-BE/TE (Segment Routing-BE/TE) data plane in the zero-trust network environment, firstly, this paper refines it into eight specific security issues. Secondly, an SR-BE/TE data plane security model ZbSR (ZTA-based SR) based on zero-trust architecture is proposed, which reconstructs the original SR control plane into a "trust-agent" two-layer plane based on 4 components of the controller, agent, cryptographic center and information base. On one hand, we distinguish between the two segment list generation modes and proposes corresponding data exchange security algorithms, by introducing north-south security verification based on identity authentication, trust evaluation, and key agreement before the terminal device establishes an east-west access connection, so reliable data exchange between terminal devices can be realized. On the other hand, for the network audit lacking SR-BE/TE, a network audit security algorithm based on solid authentication is proposed. By auditing the fields, behaviors, loops, labels, paths, and SIDs of messages, threats such as stream path tampering, SID tampering, DoS attacks, and loop attacks can be effectively detected. Finally, through the simulation test, the proposed model can provide security protection for the SR data plane with a 19.3% average incremental delay overhead for various threat scenarios.

19.
Chem Sci ; 13(32): 9381-9386, 2022 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-36093018

RESUMEN

Fluorescent dithienylethene-based photochromic materials have been attracting considerable attention owing to their wide applications in biological and materials sciences. However, the limitations of detrimental UV irradiation for photocyclization, short emission lifetime, and inefficient photoresponsive speed still need to be addressed. Herein, a novel dithienylethene photochromic molecule, BFBDTE, has been prepared by the incorporation of a difluoroboron ß-diketonate (BF2bdk) unit. The strong electron acceptor BF2bdk not only reduces the energy gap of the open isomer, ensuring visible light-controlled fluorescence switching, but also promotes intersystem crossing for the generation of thermally activated delayed fluorescence (TADF). Upon alternating irradiation with green and NIR light, BFBDTE presents a rare example of photochromism, fluorescence and TADF switching in various polar solvents and a poly(methyl methacrylate) (PMMA) film. Meanwhile, it shows rapid and well repeatable cyclization (12 s) and cycloreversion reactions (20 s) in PMMA, accompanied by fast TADF switching within 11 s. Furthermore, photo-electrochemical measurements reveal a remarkable on-off photoelectronic response (photocurrent density ratio: I light/I dark = 684) between the open- and closed-form of BFBDTE. These remarkable merits make BFBDTE promising for photoswitchable molecular devices, optical memory storage systems, NIR detectors, and photoelectric switching.

20.
J Org Chem ; 87(11): 7446-7455, 2022 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-35608344

RESUMEN

The emerging field of photopharmacology has offered a promising alternative to guard against the bacterial resistance by effectively avoiding antibiotic accumulation in the body or environment. However, the degradation, toxicity, and thermal reversibility have always been an ongoing concern for potential applications of azobenzene-based photopharmacology. Developing novel photopharmacological agents based on a more matched switch is highly in demand and remains a major challenge. Herein, two novel dithienylethene-bridged dual-fluoroquinolone derivatives have been developed by introducing two fluoroquinolone drugs into both ends of the dithienylethene (DTE) switch, in which the fluoroquinolone acts as a fluorophore except for the pharmacodynamic component. For comparison, two monofluoroquinolone-DTE hybrids were also prepared by a similar strategy. As expected, these resultant DTE-based antibacterial agents displayed efficient photochromism and fluorescence switching behavior in dimethyl sulfoxide. Moreover, improved antibacterial activities compared to those of monofluoroquinolone derivatives and a maximum fourfold active difference against Escherichia coli (E. coli) for open and closed isomers and photoswitchable bacterial imaging for Staphylococcus aureus and E. coli were observed. The molecular docking to DNA gyrase gave a rationale for the discrepancies in antibacterial activity for both isomers. Therefore, these fluoroquinolone derivatives can act as interesting imaging-guided photopharmacological agents for further in vivo studies.


Asunto(s)
Escherichia coli , Fluoroquinolonas , Antibacterianos/farmacología , Girasa de ADN/metabolismo , Girasa de ADN/farmacología , Fluoroquinolonas/farmacología , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular
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