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1.
Vaccine ; 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38714449

RESUMEN

To assess the levels of and neutralizing antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its mutants in serum samples from patients with breakthrough infection. Sixty-four patients with breakthrough infections were recruited for this cross-sectional study. All samples were used to neutralizing antibodies (nAbs) against SARS-CoV-2 and its mutants using a focused reduction neutralization assay. A total of 512 serum samples were obtained from unvaccinated patients who received one dose of vaccine (n = 12), received two doses of vaccine (n = 15), and received three doses of vaccine (n = 37). The geometric mean titer (GMT) of neutralizing antibodies against the Omicron subvariant was significantly lower (GMT 66.8 and 56.1) compared to the original strain, regardless of whether two or three doses of vaccine were administered. This result highlights that sera from breakthrough infections induce broad neutralization, but Omicron XBB.1.16 exhibits high immune evasion potential.

2.
Chem Biol Drug Des ; 103(6): e14554, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38806405

RESUMEN

This paper reports the design, synthesis, and antibacterial activity study of pleuromutilin derivatives with 2-methyl-4-nitroaniline and 2-methoxy-4-nitroaniline side chains at the C22 position. The structures of the new compounds were characterized by 1H-NMR, 13C-NMR and HRMS. The inhibitory activity of the compounds against MSSA, pyogeniccoccus, streptococcus, and MRSA strains was determined using the micro broth dilution method. The results showed that the compounds exhibited certain activity against Gram-positive bacteria, among which compounds A8a, A8b, A8c, A8d, and A7 demonstrated superior antibacterial activity against MSSA, MRSA, and pyogeniccoccus compared to tiamulin, although the derivatives showed lower antibacterial activity against streptococcus compared to the control drug. Based on the favorable in vitro activity of A8c, the time-kill kinetics against MRSA were evaluated, revealing that compound A8c could inhibit bacterial proliferation in a concentration-dependent manner.


Asunto(s)
Antibacterianos , Diterpenos , Diseño de Fármacos , Staphylococcus aureus Resistente a Meticilina , Pruebas de Sensibilidad Microbiana , Pleuromutilinas , Compuestos Policíclicos , Antibacterianos/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Diterpenos/farmacología , Diterpenos/química , Diterpenos/síntesis química , Compuestos Policíclicos/farmacología , Compuestos Policíclicos/química , Compuestos Policíclicos/síntesis química , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Relación Estructura-Actividad , Streptococcus/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos
3.
Front Pharmacol ; 15: 1380304, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38783957

RESUMEN

Introduction: Human topoisomerase 1 (TOP1) is an important target of various anticancer compounds. The design and discovery of inhibitors targeting TOP1 are of great significance for the development of anticancer drugs. Evodiamine and thieno [2,3-d] pyridine hybrids show potential antitumor activity. Herein, the anti-gastric cancer activities of these hybrids were investigated. Methods: The inhibitory effects of different concentrations of ten evodiamine derivatives on the gastric cancer cell line SGC-7901 were assessed using a methyl thiazolyl tetrazolium assay. Compounds EVO-1 and EVO-6 strongly inhibited gastric cancer cell proliferation, with inhibition rates of 81.17% ± 5.08% and 80.92% ± 2.75%, respectively. To discover the relationship between the structure and activity of these two derivatives, density functional theory was used to investigate their optimized geometries, natural population charges, frontier molecular orbitals, and molecular electrostatic potentials. To clarify their anti-gastric cancer mechanisms, molecular docking, molecular dynamics simulations, and binding free energy calculations were performed against TOP1. Results: The results demonstrated that these compounds could intercalate into the cleaved DNA-binding site to form a TOP1-DNA-ligand ternary complex, and the ligand remained secure at the cleaved DNA-binding site to form a stable ternary complex. As the binding free energy of compound EVO-1 with TOP1 (-38.33 kcal·mol-1) was lower than that of compound EVO-6 (-33.25 kcal·mol-1), compound EVO-1 could be a more potent anti-gastric cancer agent than compound EVO-6. Discussion: Thus, compound EVO-1 could be a promising anti-gastric cancer drug candidate. This study may facilitate the design and development of novel TOP1 inhibitors.

4.
Sci Total Environ ; : 173381, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38782274

RESUMEN

The chemical weathering process of carbonate rocks consumes a large quantity of CO2. This has great potential as a carbon sink, and it is one of a significant pathway for achieving carbon neutrality. However, the control mechanisms of karst carbon sink fluxes are unclear, and there is a lack of effective and accurate accounting. We took the Puding Shawan karst water­carbon cycle test site in China, which has identical initial conditions but different land use types, as the research subject. We used controlled experiments over six years to evaluate the mechanisms for the differences in hydrology, water chemistry, concentrations and fluxes of dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC). We found that the transition from rock to bare soil to grassland led to increases in the DIC concentration by 0.08-0.62 mmol⋅L-1. The inorganic carbon sink flux (CSF) increased by 3.01-5.26 t⋅C⋅km-2⋅a-1, an increase amplitude of 30-70 %. The flux of dissolved organic carbon (FDOC) increase by 0.28 to 0.52 t⋅C⋅km-2⋅a-1, an increase amplitude of 34-90 %. We also assessed the contribution of land use modifications to regional carbon neutrality, it indicate that positive land use modification can significantly regulate the karst carbon sink, with grassland having the greatest carbon sequestration ability. Moreover, in addition to DOC from soil organic matter degradation, DOC production by chemoautotrophic microorganisms utilizing DIC in groundwater may also be a potential source. Thus, coupled studies of the conversion of DIC to DOC processes in groundwater are an important step in assessing karst carbon sink fluxes.

5.
Adv Colloid Interface Sci ; 328: 103177, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38759448

RESUMEN

Pickering foam is a type of foam stabilized by solid particles known as Pickering stabilizers. These solid stabilizers adsorb at the liquid-gas interface, providing superior stability to the foam. Because of its high stability, controllability, versatility, and minimal environmental impact, nanomaterial-stabilized Pickering foam has opened up new possibilities and development prospects for foam applications. This review provides an overview of the current state of development of Pickering foam stabilized by a wide range of nanomaterials, including cellulose nanomaterials, chitin nanomaterials, silica nanoparticles, protein nanoparticles, clay mineral, carbon nanotubes, calcium carbonate nanoparticles, MXene, and graphene oxide nanosheets. Particularly, the preparation and surface modification methods of various nanoparticles, the fundamental properties of nanomaterial-stabilized Pickering foam, and the synergistic effects between nanoparticles and surfactants, functional polymers, and other additives are systematically introduced. In addition, the latest progress in the application of nanomaterial-stabilized Pickering foam in the oil industry, food industry, porous functional material, and foam flotation field is highlighted. Finally, the future prospects of nanomaterial-stabilized Pickering foam in different fields, along with directions for further research and development directions, are outlined.

6.
J Cell Mol Med ; 28(10): e18381, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38780509

RESUMEN

Peritoneal fibrosis is a common pathological response to long-term peritoneal dialysis (PD) and a major cause for PD discontinuation. Understanding the cellular and molecular mechanisms underlying the induction and progression of peritoneal fibrosis is of great interest. In our study, in vitro study revealed that signal transducer and activator of transcription 3 (STAT3) is a key factor in fibroblast activation and extracellular matrix (ECM) synthesis. Furthermore, STAT3 induced by IL-6 trans-signalling pathway mediate the fibroblasts of the peritoneal stroma contributed to peritoneal fibrosis. Inhibition of STAT3 exerts an antifibrotic effect by attenuating fibroblast activation and ECM production with an in vitro co-culture model. Moreover, STAT3 plays an important role in the peritoneal fibrosis in an animal model of peritoneal fibrosis developed in mice. Blocking STAT3 can reduce the peritoneal morphological changes induced by chlorhexidine gluconate. In conclusion, our findings suggested STAT3 signalling played an important role in peritoneal fibrosis. Therefore, blocking STAT3 might become a potential treatment strategy in peritoneal fibrosis.


Asunto(s)
Ácidos Aminosalicílicos , Fibroblastos , Fibrosis Peritoneal , Fenotipo , Factor de Transcripción STAT3 , Transducción de Señal , Fibrosis Peritoneal/metabolismo , Fibrosis Peritoneal/patología , Fibrosis Peritoneal/etiología , Fibrosis Peritoneal/genética , Factor de Transcripción STAT3/metabolismo , Animales , Fibroblastos/metabolismo , Fibroblastos/efectos de los fármacos , Fibroblastos/patología , Ratones , Ácidos Aminosalicílicos/farmacología , Transducción de Señal/efectos de los fármacos , Modelos Animales de Enfermedad , Peritoneo/patología , Peritoneo/metabolismo , Interleucina-6/metabolismo , Matriz Extracelular/metabolismo , Masculino , Ratones Endogámicos C57BL , Humanos , Clorhexidina/análogos & derivados , Clorhexidina/farmacología , Diálisis Peritoneal/efectos adversos , Bencenosulfonatos
7.
BMC Cancer ; 24(1): 582, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38741069

RESUMEN

BACKGROUND: Local recurrence after surgery and radiochemotherapy seriously affects the prognosis of locally advanced rectal cancer (LARC) patients. Studies on molecular markers related to the radiochemotherapy sensitivity of cancers have been widely carried out, which might provide valued information for clinicians to carry out individual treatment. AIM: To find potential biomarkers of tumors for predicting postoperative recurrence. METHODS: In this study, LARC patients undergoing surgery and concurrent radiochemotherapy were enrolled. We focused on clinicopathological factors and PTEN, SIRT1, p-4E-BP1, and pS6 protein expression assessed by immunohistochemistry in 73 rectal cancer patients with local recurrence and 76 patients without local recurrence. RESULTS: The expression of PTEN was higher, while the expression of p-4E-BP1 was lower in patients without local recurrence than in patients with local recurrence. Moreover, TNM stage, lymphatic vessel invasion (LVI), PTEN and p-4E-BP1 might be independent risk factors for local recurrence after LARC surgery combined with concurrent radiochemotherapy. CONCLUSIONS: This study suggests that PTEN and p-4E-BP1 might be potential biomarkers for prognostic prediction and therapeutic targets for LARC.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Biomarcadores de Tumor , Proteínas de Ciclo Celular , Quimioradioterapia , Recurrencia Local de Neoplasia , Fosfohidrolasa PTEN , Neoplasias del Recto , Humanos , Neoplasias del Recto/terapia , Neoplasias del Recto/patología , Neoplasias del Recto/metabolismo , Fosfohidrolasa PTEN/metabolismo , Masculino , Femenino , Persona de Mediana Edad , Quimioradioterapia/métodos , Biomarcadores de Tumor/metabolismo , Anciano , Pronóstico , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas de Ciclo Celular/metabolismo , Fosfoproteínas/metabolismo , Adulto , Estadificación de Neoplasias
8.
Science ; 384(6697): 776-781, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38753798

RESUMEN

Sophisticated statistical mechanics approaches and human intuition have demonstrated the possibility of self-assembling complex lattices or finite-size constructs. However, attempts so far have mostly only been successful in silico and often fail in experiment because of unpredicted traps associated with kinetic slowing down (gelation, glass transition) and competing ordered structures. Theoretical predictions also face the difficulty of encoding the desired interparticle interaction potential with the experimentally available nano- and micrometer-sized particles. To overcome these issues, we combine SAT assembly (a patchy-particle interaction design algorithm based on constrained optimization) with coarse-grained simulations of DNA nanotechnology to experimentally realize trap-free self-assembly pathways. We use this approach to assemble a pyrochlore three-dimensional lattice, coveted for its promise in the construction of optical metamaterials, and characterize it with small-angle x-ray scattering and scanning electron microscopy visualization.


Asunto(s)
Algoritmos , ADN , Nanotecnología , ADN/química , Nanotecnología/métodos , Dispersión del Ángulo Pequeño , Difracción de Rayos X , Nanoestructuras/química , Conformación de Ácido Nucleico , Microscopía Electrónica de Rastreo
9.
Sensors (Basel) ; 24(9)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38732862

RESUMEN

Online monitoring and real-time feedback on inclusions in molten metal are essential for metal quality control. However, existing methods for detecting aluminum melt inclusions face challenges, including interference, prolonged processing times, and latency. This paper presents the design and development of an online monitoring system for molten metal inclusions. Initially, the system facilitates real-time adjustment of signal acquisition parameters through a multiplexer. Subsequently, it employs a detection algorithm capable of swiftly extracting pulse peaks, with this task integrated into our proprietary host computer software to ensure timely detection and data visualization. Ultimately, we developed a monitoring device integrated with this online monitoring system, enabling the online monitoring of the aluminum alloy filtration process. Our findings indicate that the system can accurately measure the size and concentration of inclusions during the filtration process in real time, offering enhanced detection speed and stability compared to the industrial LiMCA CM (liquid metal cleanliness analyzer continuous monitoring) standard. Furthermore, our evaluation of the filtration process demonstrates that the effectiveness of filtration significantly improves with the increase in inclusion sizes, and the synergistic effect of combining CFF (ceramic foam filter) and MCF (metallics cartridge filter) filtration methods exceeds the performance of the CFF method alone. This system thus provides valuable technical support for optimizing filtration processes and controlling inclusion quality.

10.
Sensors (Basel) ; 24(9)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38732873

RESUMEN

Traditional methods for assessing the cleanliness of liquid metal are characterized by prolonged detection times, delays, and susceptibility to variations in sampling conditions. To address these limitations, an online cleanliness-analyzing system grounded in the method of the electrical sensing zone has been developed. This system facilitates real-time, in situ, and quantitative analysis of inclusion size and amount in liquid metal. Comprising pneumatic, embedded, and host computer modules, the system supports the continuous, online evaluation of metal cleanliness across various metallurgical processes in high-temperature environments. Tests conducted with gallium liquid at 90 °C and aluminum melt at 800 °C have validated the system's ability to precisely and quantitatively detect inclusions in molten metal in real time. The detection procedure is stable and reliable, offering immediate data feedback that effectively captures fluctuations in inclusion amount, thereby meeting the metallurgical industry's demand for real-time analyzing and control of inclusion cleanliness in liquid metal. Additionally, the system was used to analyze inclusion size distribution during the hot-dip galvanizing process. At a zinc melt temperature of 500 °C, it achieved a detection limit of 21 µm, simultaneously providing real-time data on the size and amount distribution of inclusions. This represents a novel strategy for the online monitoring and quality control of zinc slag throughout the hot-dip galvanizing process.

12.
Med Biol Eng Comput ; 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38789838

RESUMEN

Many major diseases of the retina often show symptoms of lesions in the fundus of the eye. The extraction of blood vessels from retinal fundus images is essential to assist doctors. Some of the existing methods do not fully extract the detailed features of retinal images or lose some information, making it difficult to accurately segment capillaries located at the edges of the images. In this paper, we propose a multi-scale retinal vessel segmentation network (SCIE_Net) based on skip connection information enhancement. Firstly, the network processes retinal images at multiple scales to achieve network capture of features at different scales. Secondly, the feature aggregation module is proposed to aggregate the rich information of the shallow network. Further, the skip connection information enhancement module is proposed to take into account the detailed features of the shallow layer and the advanced features of the deeper network to avoid the problem of incomplete information interaction between the layers of the network. Finally, SCIE_Net achieves better vessel segmentation performance and results on the publicly available retinal image standard datasets DRIVE, CHASE_DB1, and STARE.

13.
Cell Biol Toxicol ; 40(1): 38, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38789868

RESUMEN

Ensartinib, an approved ALK inhibitor, is used as a first-line therapy for advanced ALK-positive non-small cell lung cancer in China. However, the hepatotoxicity of ensartinib seriously limits its clinical application and the regulatory mechanism is still elusive. Here, through transcriptome analysis we found that transcriptional activation of TXNIP was the main cause of ensartinib-induced liver dysfunction. A high TXNIP level and abnormal TXNIP translocation severely impaired hepatic function via mitochondrial dysfunction and hepatocyte apoptosis, and TXNIP deficiency attenuated hepatocyte apoptosis under ensartinib treatment. The increase in TXNIP induced by ensartinib is related to AKT inhibition and is mediated by MondoA. Through screening potential TXNIP inhibitors, we found that the natural polyphenolic flavonoid rutin, unlike most reported TXNIP inhibitors can inhibit TXNIP by binding to TXNIP and partially promoting its proteasomal degradation. Further studies showed rutin can attenuate the hepatotoxicity of ensartinib without antagonizing its antitumor effects. Accordingly, we suggest that TXNIP is the key cause of ensartinib-induced hepatotoxicity and rutin is a potential clinically safe and feasible therapeutic strategy for TXNIP intervention.


Asunto(s)
Apoptosis , Proteínas Portadoras , Rutina , Rutina/farmacología , Proteínas Portadoras/metabolismo , Proteínas Portadoras/genética , Humanos , Animales , Apoptosis/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Ratones , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Enfermedad Hepática Inducida por Sustancias y Drogas/genética , Masculino
14.
Blood Adv ; 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38701354

RESUMEN

Despite therapeutic advancements, GVHD is a major complication of HSCT. In current models of GVHD, tissue injury induced by cytotoxic conditioning regimens, along with translocation of microbes expressing Pathogen Associated Molecular Patterns (PAMPs), result in activation of host antigen-presenting cells (APC) to stimulate alloreactive donor T lymphocytes. Recent studies have demonstrated that in many pathologic states, tissue injury results in the release of mitochondria from the cytoplasm to the extracellular space. We hypothesized that extracellular mitochondria, which are related to archaebacteria, could also trigger GVHD by stimulation of host APC. We found that clinically relevant doses of radiation or busulfan induced extracellular release of mitochondria by various cell types, including cultured intestinal epithelial cells. Conditioning-mediated mitochondrial release was associated with mitochondrial damage and impaired quality control but did not affect the viability of the cells. Extracellular mitochondria directly stimulated host APCs to express higher levels of MHC-II, co-stimulatory CD86, and pro-inflammatory cytokines, resulting in increased donor T cell activation, and proliferation in mixed lymphocyte reactions. Analyses of plasma from both experimental mice and a cohort of children undergoing HSCT demonstrated that conditioning induced extracellular mitochondrial release in vivo. In mice undergoing MHC mismatched HSCT, administration of purified syngeneic extracellular mitochondria increased host APC activation and exacerbated GVHD. Our data suggests that pre-HSCT conditioning results in extracellular release of damaged mitochondria which increase alloreactivity and exacerbate GVHD. Therefore, decreasing the extracellular release of damaged mitochondria following conditioning could serve as a novel strategy for GVHD prevention.

15.
Toxicol Lett ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38754640

RESUMEN

Lenvatinib is a multi-target inhibitor that exerts anti-tumor effects by inhibiting angiogenesis and is now commonly used as a first-line treatment for hepatocellular carcinoma. However, with the widespread use of lenvatinib, the problem of serious and fatal hepatotoxicity has become increasingly prominent. Currently, the mechanism behind this toxicity is not yet understood, and as a result, there is a lack of safe and effective intervention strategies with minimal side effects. Here, we established the model of lenvatinib-induced liver injury in vivo and in vitro and found that lenvatinib caused hepatotoxicity by inducing apoptosis. Further mechanistic studies in cellular models revealed that lenvatinib upregulated death receptor signaling pathway, which activated the downstream effector Caspase-8, and ultimately led to apoptosis. Meanwhile, lenvatinib-induced apoptosis was associated with ROS generation and DNA damage. In addition, after screening marketed drugs and natural products in combination with cellular modeling, we identified a potential co-administered drug, dabrafenib, which could alleviate lenvatinib-induced hepatotoxicity. Further mechanistic studies revealed that dabrafenib attenuated lenvatinib-induced hepatotoxicity by inhibiting the activation of the death receptor signaling pathway. Subsequently, cancer cell proliferation assays confirmed that dabrafenib did not antagonize the antitumor effects of lenvatinib. In conclusion, our results validate that apoptosis caused by the death receptor signaling pathway is the key cause of lenvatinib-induced hepatotoxicity, and dabrafenib alleviates lenvatinib-induced hepatotoxicity by inhibiting this pathway.

16.
Phys Rev E ; 109(4-1): 044502, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38755928

RESUMEN

Chromatin polymer dynamics are commonly described using the classical Rouse model. The subsequent discovery, however, of intermediate-scale chromatin organization known as topologically associating domains (TADs) in experimental Hi-C contact maps for chromosomes across the tree of life, together with the success of loop extrusion factor (LEF) model in explaining TAD formation, motivates efforts to understand the effect of loops and loop extrusion on chromatin dynamics. This paper seeks to fulfill this need by combining LEF-model simulations with extended Rouse-model polymer simulations to investigate the dynamics of chromatin with loops and dynamic loop extrusion. We show that loops significantly suppress the averaged mean-square displacement (MSD) of a gene locus, consistent with recent experiments that track fluorescently labeled chromatin loci. We also find that loops reduce the MSD's stretching exponent from the classical Rouse-model value of 1/2 to a loop-density-dependent value in the 0.45-0.40 range. Remarkably, stretching exponent values in this range have also been observed in recent experiments [Weber et al., Phys. Rev. Lett. 104, 238102 (2010)0031-900710.1103/PhysRevLett.104.238102; Bailey et al., Mol. Biol. Cell 34, ar78 (2023)1059-152410.1091/mbc.E23-04-0119]. We also show that the dynamics of loop extrusion itself negligibly affects chromatin mobility. By studying static "rosette" loop configurations, we also demonstrate that chromatin MSDs and stretching exponents depend on the location of the locus in question relative to the position of the loops and on the local friction environment.


Asunto(s)
Cromatina , Cromatina/metabolismo , Cromatina/genética , Cromatina/química , Modelos Moleculares
17.
Microb Biotechnol ; 17(5): e14472, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38683679

RESUMEN

The availability of an alternative and efficient genetic editing technology is critical for fundamental research and strain improvement engineering of Streptomyces species, which are prolific producers of complex secondary metabolites with significant pharmaceutical activities. The mobile group II introns are retrotransposons that employ activities of catalytic intron RNAs and intron-encoded reverse transcriptase to precisely insert into DNA target sites through a mechanism known as retrohoming. We here developed a group II intron-based gene editing tool to achieve precise chromosomal gene insertion in Streptomyces. Moreover, by repressing the potential competition of RecA-dependent homologous recombination, we enhanced site-specific insertion efficiency of this tool to 2.38%. Subsequently, we demonstrated the application of this tool by screening and characterizing the secondary metabolite biosynthetic gene cluster (BGC) responsible for synthesizing the red pigment in Streptomyces roseosporus. Accompanied with identifying and inactivating this BGC, we observed that the impair of this cluster promoted cell growth and daptomycin production. Additionally, we applied this tool to activate silent jadomycin BGC in Streptomyces venezuelae. Overall, this work demonstrates the potential of this method as an alternative tool for genetic engineering and cryptic natural product mining in Streptomyces species.


Asunto(s)
Intrones , Familia de Multigenes , Streptomyces , Streptomyces/genética , Streptomyces/metabolismo , Intrones/genética , Edición Génica/métodos , Mutagénesis Insercional/métodos , Metabolismo Secundario/genética , Vías Biosintéticas/genética , Recombinación Homóloga
18.
Artículo en Inglés | MEDLINE | ID: mdl-38603469

RESUMEN

The electrochemical interface formed between an electrode and an electrolyte significantly affects the rate and mechanism of the electrode reaction through its structure and properties, which vary across the interface. The scope of the interface has been expanded, along with the development of energy electrochemistry, where a solid-electrolyte interphase may form on the electrode and the active materials change properties near the surface region. Developing a comprehensive understanding of electrochemical interfaces and interphases necessitates three-dimensional spatial resolution characterization. Atomic force microscopy (AFM) offers advantages of imaging and long-range force measurements. Here we assess the capabilities of AFM by comparing the force curves of different regimes and various imaging modes for in situ characterizing of electrochemical interfaces and interphases. Selected examples of progress on work related to the structures and processes of electrode surfaces, electrical double layers, and lithium battery systems are subsequently illustrated. Finally, this review provides perspectives on the future development of electrochemical AFM.

19.
Microbiol Spectr ; : e0041324, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38687069

RESUMEN

Our study aims to investigate the impact of probiotic consumption during pregnancy on gut microbiota functional diversity in healthy pregnant women. Thirty-two pregnant women were randomly assigned to two groups. The probiotic group (PG) consisted of pregnant women who consumed triple viable Bifidobacterium longum, Lactobacillus delbrueckii bulgaricus, and Streptococcus thermophilus tablets from the 32nd week of pregnancy until delivery. The functional profiles of the gut microbiota were predicted through high-throughput 16S rRNA sequencing results using PICRUSt software and referencing the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. In the gut microbiota of the PG, the genera Blautia and Ruminococcus, as well as the species Subdoligranulum, showed significantly higher relative abundances compared to the control group (CG) (P < 0.05). At Level 1 of the KEGG signaling pathways, there was a significant reduction in the functional genes of the gut microbiota involved in Organismal Systems in the PG (P < 0.05). In Level 2 of the KEGG signaling pathways, there was a significant reduction in the functional genes of the gut microbiota involved in Infectious Disease in the PG (P < 0.05). In Level 3 of the KEGG signaling pathways, the PG exhibited a significant increase in the functional genes of the gut microbiota involved in ABC transporters, Oxidative phosphorylation, Folate biosynthesis, and Biotin metabolism (P < 0.05). The CG showed a significant increase in the functional genes related to Cysteine and methionine metabolism, Vitamin B6 metabolism, Tuberculosis, and Vibrio cholerae pathogenic cycle (P < 0.05). In conclusion, our findings suggest that probiotic supplementation during pregnancy has a significant impact on functional metabolism in healthy pregnant women. IMPORTANCE: Probiotics are considered beneficial to human health. There is limited understanding of how probiotic consumption during pregnancy affects the functional diversity of the gut microbiota. The aim of our study is to investigate the impact of probiotic consumption during pregnancy on the functional diversity of the gut microbiota. Our findings suggest that probiotic supplementation during pregnancy has a significant impact on functional metabolism. This could potentially open up new avenues for preventing various pregnancy-related complications. This also provides new insights into the effects of probiotic consumption during pregnancy on the gut microbiota and offers a convenient method for exploring the potential mechanisms underlying the impact of probiotics on the gut microbiota of pregnant women.

20.
BMC Med ; 22(1): 146, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38561734

RESUMEN

BACKGROUND: Childhoods in urban or rural environments may differentially affect the risk of neuropsychiatric disorders, possibly through memory processing and neural response to emotional stimuli. Genetic factors may not only influence individuals' choices of residence but also modulate how the living environment affects responses to episodic memory. METHODS: We investigated the effects of childhood urbanicity on episodic memory in 410 adults (discovery sample) and 72 adults (replication sample) with comparable socioeconomic statuses in Beijing, China, distinguishing between those with rural backgrounds (resided in rural areas before age 12 and relocated to urban areas at or after age 12) and urban backgrounds (resided in cities before age 12). We examined the effect of childhood urbanicity on brain function across encoding and retrieval sessions using an fMRI episodic memory paradigm involving the processing of neutral or aversive pictures. Moreover, genetic association analyses were conducted to understand the potential genetic underpinnings that might contribute to memory processing and neural mechanisms influenced by early-life urban or rural environments. RESULTS: Episodic memory retrieval accuracy for more difficult neutral stimuli was similar between those with urban and rural childhoods, whereas aversive stimuli elicited higher retrieval accuracy in the urban group (P = 0.023). For aversive stimuli, subjects with urban childhood had relatively decreased engagement of the striatum at encoding and decreased engagement of the hippocampus at retrieval. This more efficient striatal encoding of aversive stimuli in those with urban childhoods was associated with common variation in neurotrophic tyrosine kinase receptor type 2 (NTRK2) (right striatum: P = 1.58×10-6). These findings were confirmed in the replication sample. CONCLUSIONS: We suggest that this differential striatal processing of aversive stimuli observed in individuals with urban or rural childhoods may represent mechanisms by which childhood urbanicity may affect brain circuits, heightening behavioral responses to negative stressors associated with urban environments. NTRK2-associated neural processes in the striatum may play a role in these processes.


Asunto(s)
Memoria Episódica , Adulto , Niño , Humanos , Mapeo Encefálico , Emociones/fisiología , Hipocampo , Imagen por Resonancia Magnética , Receptor trkB
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