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1.
Artículo en Inglés | MEDLINE | ID: mdl-37115596

RESUMEN

Members of the genus Novosphingobium were frequently isolated from polluted environments and possess great bioremediation potential. Here, three species, designated B2637T, B2580T and B1949T, were isolated from mangrove sediments and might represent novel species in the genus Novosphingobium based on a polyphasic taxonomy study. Phylogenomic analysis revealed that strains B2580T, B1949T and B2637T clustered with Novosphingobium naphthalenivorans NBRC 102051T, 'N. profundi' F72 and N. decolorationis 502str22T, respectively. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between isolates and their closely related species were less than 94 and 54 %, respectively, all below the threshold of species discrimination. The sizes of the genomes of isolates B2580T, B2637T and B1949T ranged from 4.4 to 4.6 Mb, containing 63.3-66.4 % G+C content. Analysis of their genomic sequences identified genes related to pesticide degradation, heavy-metal resistance, nitrogen fixation, antibiotic resistance and sulphur metabolism, revealing the biotechnology potential of these isolates. Except for B2637T, B1949T and B2580T were able to grow in the presence of quinalphos. Results from these polyphasic taxonomic analyses support the affiliation of these strains to three novel species within the genus Novosphingobium, for which we propose the name Novosphingobium album sp. nov. B2580T (=KCTC 72967T=MCCC 1K04555T), Novosphingobium organovorum sp. nov. B1949T (=KCTC 92158T=MCCC 1K03763T) and Novosphingobium mangrovi sp. nov. B2637T (KCTC 72969T=MCCC 1K04460T).


Asunto(s)
Ácidos Grasos , Plaguicidas , Ácidos Grasos/química , Compuestos Organofosforados , Análisis de Secuencia de ADN , Filogenia , Composición de Base , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , ARN Ribosómico 16S/genética , Hibridación de Ácido Nucleico , Fosfolípidos
2.
Appl Microbiol Biotechnol ; 107(20): 6325-6338, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37566161

RESUMEN

Streptomyces species are ubiquitous, Gram-positive, spore-forming bacteria with the ability to produce various clinically relevant compounds. The strain 4503 T was isolated from mangrove sediments, showing morphological and chemical properties which were consistent with those of members of the genus Streptomyces. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the isolate was primarily identified as members of the genus Streptomyces, sharing more than 99% sequence identity to Streptomyces yatensis DSM 41771 T, S. antimycoticus NBRC 12839 T, and S. melanosporofaciens NBRC 13061 T. Average nucleotide identities (ANI) and digital DNA-DNA hybridization (dDDH) values between strain 4503 T and its close relatives were all below 95-96% and 75% of the novel species threshold, respectively. Results from phylogenetic, genomic, phenotypic, and chemotaxonomic characteristics analyses confirmed that the isolate represented a novel species of the genus Streptomyces, for which the name Streptomyces niphimycinicus sp. nov. 4503 T (= MCCC 1K04557T = JCM 34996 T) is proposed. The bioassay-guided fractionation of the extract of strain 4503 T resulted in the isolation of a known compound niphimycin C, which showed cytotoxic activity against nasopharyngeal carcinoma (NPC) cell lines TW03 and 5-8F with half maximal inhibitory concentration (IC50) values of 12.24 µg/mL and 9.44 µg/mL, respectively. Further experiments revealed that niphimycin C not only exhibited the capacity of anti-proliferation, anti-metastasis, induction of cell cycle arrest, and apoptosis, but was also able to increase the reactive oxygen species (ROS) production and regulate several signaling pathways in NPC cells. KEY POINTS: • Strain 4503 T was classified as a novel species of Streptomyces. • Niphimycin C correlates with the cytotoxic effect of strain 4503 T against NPC cells. • Niphimycin C induces apoptosis, autophagic flux disruption and cell cycle arrest.


Asunto(s)
Neoplasias Nasofaríngeas , Streptomyces , Humanos , Filogenia , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/metabolismo , Carcinoma Nasofaríngeo/tratamiento farmacológico , Microbiología del Suelo , ADN Bacteriano/química , Técnicas de Tipificación Bacteriana , Streptomyces/metabolismo , Neoplasias Nasofaríngeas/tratamiento farmacológico , Ácidos Grasos/metabolismo , Análisis de Secuencia de ADN
3.
Antonie Van Leeuwenhoek ; 116(11): 1151-1159, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37658956

RESUMEN

A novel Novosphingobium species, designated strain B2638T, was isolated from mangrove sediments which was collected from Beibu Gulf, Beihai, P. R. China. The isolate could grow in the presence of chlorpyrifos. Phylogenetic analysis based on 16S rRNA gene sequence revealed that the isolate belonged to the genus Novosphingobium, showing 99.9% sequence similarity with N. decloroationis 502str22T and less than 98% similarity with other type strain of species of this genus. Molecular typing by BOX-PCR divided strain B2638T and N. declorationis 502str22T into two clusters and indicated that they were not identical. Genomic comparison referenced by values of the DNA-DNA hybridization (dDDH) and the average nucleotide identity (ANI) between strain B2638T and its close phylogenetic neighbors were 20.0-29.5% and 75.3-85.3%, respectively, that were lower than proposed thresholds for bacterial species delineation. The major fatty acids (> 10%) were identified as C18:1 ω7c, C17:1 iso ω9c and C16:0. The main polar lipids contained diphosphatidylglycerol, phosphatidylethanolamine, sphingoglycolipid, phosphatidyl glycerol, unidentified lipid and unidentified aminolipid. Results from phenotypic, chemotaxonomic and genotypic analyses proposed that strain B2638T (= MCCC 1K07406T = KCTC 72968 T) is represented a novel species in the genus Novosphingobium, for which the names Novosphingobium beihaiensis sp. nov. is proposed.


Asunto(s)
Plaguicidas , Sphingomonadaceae , Filogenia , ARN Ribosómico 16S/genética , Técnicas de Tipificación Bacteriana , Análisis de Secuencia de ADN , Ácidos Grasos , ADN , ADN Bacteriano/genética , Fosfolípidos , Hibridación de Ácido Nucleico
4.
Int J Syst Evol Microbiol ; 72(10)2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36282561

RESUMEN

Two novel actinobacteria with the ability to degrade kerosene, designated as B3033T and Y57T, were isolated from mangrove sediments in Tieshan Harbour, South China Sea. Both strains are Gram-staining-positive, non-spore forming, slow-growing, oxidase-positive, non-motile and aerobic. Their major cellular fatty acids were C16 : 0 and C18 : 1ω9c. Analysis of 16S rRNA gene sequences revealed the close relationship of strain B3033T to Mycobacterium kyogaense DSM 107316T (99.4 % nucleotide identity) and strain Y57T to Mycolicibacterium chubuense ATCC 27278T (98.7 %) and Mycolicibacterium rufum JS14T (98.7 %). Whole genome average nucleotide blast identity (ANI) and the digital DNA-DNA hybridization (dDDH) values between the two isolates and the type strains of species of the genus Mycolicibacterium were lower than 94 and 45 %, respectively, which were below the threshold values of 95 % (for ANI) and 70 % (for dDDH) recommended for bacterial species differentiation. The genome sequence of B3033T comprised a circular 11.0 Mb chromosome with a DNA G+C content of 68.1 mol%. Y57T had a genome size of 5.6 Mb and a DNA G+C content of 68.7 mol%. Genes involved in degradation of aromatic compounds and copper resistance were identified in the genomes of both strains that could improve their adaptive capacity to the mangrove environment. These results combined with those of chemotaxonomic analyses, MALDI-TOF MS profiles and phenotypic analyses support the affiliation of these strains to two novel species within the genus Mycolicibacterium, for which we propose the names Mycolicibacterium aurantiacum sp. nov. B3033T (=KCTC 49712T=MCCC 1K04526T) and Mycolicibacterium xanthum sp. nov. Y57T (=KCTC 49711T=MCCC 1K04875T) as type strains.


Asunto(s)
Actinobacteria , Técnicas de Tipificación Bacteriana , Composición de Base , Cobre , ADN Bacteriano/genética , Ácidos Grasos/química , Queroseno , Hibridación de Ácido Nucleico , Nucleótidos , Oxidorreductasas/genética , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Sedimentos Geológicos
5.
Artículo en Inglés | MEDLINE | ID: mdl-33406032

RESUMEN

A Gram-stain-negative, aerobic, mesophilic, non-motile bacterium, designated M0104T, was isolated from a gorgonian coral collected from Xieyang island, Guangxi Province, PR China. Colonies of the strain were non-motile cocci and pink. The strain grew at 15-34 °C (optimum, 28 °C), pH 4.5-8.0 (optimum, pH 7.0) and with 0-4% (w/v) NaCl (optimum, 0-2 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain M0104T was closely related to Roseomonas deserti JCM 31275T (96.2 %), Roseomonas vastitatis KCTC 62043T (96.0 %), Roseomonas aerofrigidensis JCM 31878T (95.9 %) and Roseomonas oryzae KCTC 42542T (95.7 %). The strain had an assembly size of 5.0 Mb and a G+C content of 71.0mol%. Genes involved in copper, cadmium, lead, arsenic and zinc resistance were identified in the genome of strain M0104T. The digital DNA-DNA hybridization and average nucleotide identity values between the genome sequence of strain M0104T and those of closely related type strains were 19.4-24.9 % and 74.3-81.8 %, respectively. Strain M0104T contained C18:1 ω7c, C18:3 ω3c, anteiso C11:0 and C16:0 as the major fatty acids (>7 %) and ubiquinone Q-10 as the sole isoprenoid quinone. Diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine were its major polar lipids. Based on its phenotypic, phylogenetic and chemotaxonomic properties, strain M0104T is proposed to represent a novel species within the genus Roseomonas, for which the name Roseomonas coralli sp. nov. is proposed. The type strain is M0104T (=KCTC 62359T=MCCC 1K03632T).


Asunto(s)
Antozoos/microbiología , Metales Pesados , Methylobacteriaceae/clasificación , Filogenia , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Methylobacteriaceae/aislamiento & purificación , Hibridación de Ácido Nucleico , Fosfolípidos/química , Pigmentación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ubiquinona/análogos & derivados , Ubiquinona/química
6.
Int J Syst Evol Microbiol ; 71(12)2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34874250

RESUMEN

A Gram-stain-negative, aerobic, milky white bacterium, designated B2012T, was isolated from mangrove sediment collected at Beibu Gulf, South China Sea. Antimicrobial activity assay revealed that the isolate possesses the capability of producing antibacterial compounds. Strain B2012T shared the highest 16S rRNA gene sequence relatedness (96.9-95.5 %) with members of the genus Acuticoccus. The isolate and all known Acuticoccus species contain Q-10 as the main respiratory quinone and have the same polar lipid components (phosphatidylcholine, unidentified glycolipid, unidentified lipid, unidentified amino lipid and phosphatidylglycerol). However, genomic relatedness referred by values of average nucleotide identity, digital DNA-DNA hybridization, average amino acid identity and the percentage of conserved proteins between strain B2012T and other type strains of the genus Acuticoccus were below the proposed thresholds for species discrimination. The genome of strain B2012T was assembled into 65 scaffolds with an N50 size of 244239 bp, resulting in a 5.5 Mb genome size. Eight secondary metabolite biosynthetic gene clusters were detected in this genome, including three non-ribosomal peptide biosynthetic loci encoding yet unknown natural products. Strain B2012T displayed moderately halophilic and alkaliphilic properties, growing optimally at 2-3 % (w/v) NaCl concentration and at pH 8-9. The major cellular fatty acids (>10 %) were anteiso-C15 : 0, C16 : 0 dimethyl aldehyde (DMA) and C16 : 0. Combined data from phenotypic, genotypic and chemotaxonomic analyses suggested that strain B2012T represents a novel species of the genus Acuticoccus, for which the name Acuticoccus mangrovi sp. nov. is proposed. The type strain of the type species is B2012T (=MCCC 1K04418T=KCTC 72962T).


Asunto(s)
Alphaproteobacteria/clasificación , Sedimentos Geológicos/microbiología , Filogenia , Alphaproteobacteria/aislamiento & purificación , Antibacterianos/farmacología , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ubiquinona/análogos & derivados , Ubiquinona/química , Humedales
7.
Artículo en Inglés | MEDLINE | ID: mdl-34181514

RESUMEN

Members within the family Rhodbacteraceae are morphologically and genetically highly diverse, and originate mostly from coastal marine environments. In this study, a novel species of this family, designated M0103T, was isolated from the surface of a sea snail Littorina scabra. Strain M0103T is Gram-stain-negative, halophilic, non-motile and non-Bacteriochlorophyll a-producing bacterium. Several phenotypic characteristics of the isolate were similar to other species within this family, such as the sole respiratory quinone Q-10 and major fatty acid components C18 : 1 ω7c, C18 : 0 and C16 : 0. Strain M0103T contains a diphosphatidylglycerol, a phosphatidylglycerol, a phosphatidylcholine, a phosphatidy ethanolamine, a phosphatidylinositol, five unidentified phospholipids and four unidentified polar lipids. Based on the 16S rRNA gene sequence analysis, this isolate showed the closest phylogenetic relationship with 'Palleronia pontilimi' GH1-23T (95.1 %). Values of average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) of genome sequences were of 70.1-76.4 % and 18.3-20.9 % between the isolate and 24 closely related type strains. Analysis the 4.0 Mb genome of strain M0103T revealed several putative genes associated with cellular stress resistance, which may play protective roles for the isolate in the adaptation to a marine environment. Phylogenetic, phenotypic and chemotaxonomic analyses suggested that strain M0103T represents a novel genus and novel species of the family Rhodobacteraceae, for which the name Mesobaculum littorinae gen. nov., sp. nov. is proposed. The type strain is M0103T (=MCCC 1K03619T=KCTC 62358T).


Asunto(s)
Lactobacillales/aislamiento & purificación , Caracoles/microbiología , Animales , Técnicas de Tipificación Bacteriana , Ácidos Grasos/análisis , Ácidos Grasos/química , Lactobacillales/genética , Hibridación de Ácido Nucleico , Fosfolípidos/análisis , Fosfolípidos/química , Filogenia , ARN Ribosómico 16S/genética , Agua de Mar/microbiología
8.
Antonie Van Leeuwenhoek ; 114(11): 1819-1828, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34424448

RESUMEN

A novel moderately thermophilic and halophilic bacterium, designated strain M0105T, was isolated from mangrove sediment collected in the Beibu Gulf, south China. The isolate is Gram-negative, non-motile and rod-shaped bacterium with smooth colonies of pale-yellow appearance. Growth occurs at 15-46 °C (optimum 37-40 °C) and pH range of 6.0-10.0 (optimum pH 8.0-9.0). It required 1-7% NaCl (optimum 3-5%) for growth. Strain M0105T was affiliated to the family 'Rhodobacteraceae', sharing the highest 16S rRNA gene sequence similarity with Limibaculum halophilum CAU 1123T (96.8%). The major menaquinone Q-10 and the dominant unsaturated fatty acid (C18:1ω7) in this family were also detected in the strain M0105T. The genome sequence possesses a circular 4.1 Mb chromosome with a G + C content of 67.9%. Strain M0105T encoded many genes for cellular stress resistance and nutrient utilization, which could improve its adaptive capacity to the mangrove environment. Values of conserved proteins (POCP), average nucleotide identity, average amino acid identity (AAI) and DNA-DNA hybridization (dDDH) between the isolate and closely related species were below the proposed threshold for species discrimination. Information from phenotypic, chemotaxonomic and phylogenetic analyses proposed that strain M0105T should be assigned to a novel genus within the family 'Rhodobacteraceae'. Thus, we suggested that the strain M0105T represents a novel species in a new genus, for which the name Thermohalobaculum xanthum gen. nov., sp. nov. is proposed. The type strain of the type species is M0105T (= BGMRC 2019T = KCTC 52118T = MCCC 1K03767T = NBRC 112057T).


Asunto(s)
Ácidos Grasos , Fosfolípidos , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Ácidos Grasos/análisis , Fosfolípidos/análisis , Filogenia , ARN Ribosómico 16S/genética , Rhodobacteraceae , Análisis de Secuencia de ADN , Ubiquinona
9.
Opt Lett ; 45(5): 1071-1074, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32108772

RESUMEN

In this Letter, we propose a new (to the best of our knowledge), promising concept of a hybrid femtosecond (fs) laser processing method composed of single-point scanning and holographic light modulation fabrication for manufacturing a tunable-size microtrap chip. The hybrid method not only ensures key microfluidic device precision but also greatly improves the fabrication speed. By using a new asymmetry-bracket-shaped microtrap design with a mechanical strain stretching method, real-time size-tunable trapping is obtained, and a 100% particle trapping retention is realized, ignoring the flow fluctuation. Finally, the microtrap array is successfully applied to trap single yeast cells and hold them for $\sim{10}\;{\rm h}$∼10h without escaping.

10.
Sensors (Basel) ; 20(10)2020 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-32456053

RESUMEN

During the variable spray process, the micro-flow control is often held back by such problems as low initial sensitivity, large inertia, large hysteresis, nonlinearity as well as the inevitable difficulties in controlling the size of the variable spray droplets. In this paper, a novel intelligent double closed-loop control with chaotic optimization and adaptive fuzzy logic is developed for a multi-sensor based variable spray system, where a Bang-Bang relay controller is used to speed up the system operation, and adaptive fuzzy nonlinear PID is employed to improve the accuracy and stability of the system. With the chaotic optimization of controller parameters, the system is globally optimized in the whole solution space. By applying the proposed double closed-loop control, the variable pressure control system includes the pressure system as the inner closed-loop and the spray volume system as the outer closed-loop. Thus, the maximum amount of spray droplets deposited on the plant surface may be achieved with the minimum medicine usage for plants. Multiple sensors (for example: three pressure sensors and two flow rate sensors) are employed to measure the system states. Simulation results show that the chaotic optimized controller has a rise time of 0.9 s, along with an adjustment time of 1.5 s and a maximum overshoot of 2.67% (in comparison using PID, the rise time is 2.2 s, the adjustment time is 5 s, and the maximum overshoot is 6.0%). The optimized controller parameters are programmed into the hardware to control the established variable spray system. The experimental results show that the optimal spray pressure of the spray system is approximately 0.3 MPa, and the flow rate is approximately 0.08 m3/h. The effective droplet rate is 89.4%, in comparison to 81.3% using the conventional PID control. The proposed chaotically optimized composite controller significantly improved the dynamic performance of the control system, and satisfactory control results are achieved.

11.
Opt Express ; 25(14): 16739-16753, 2017 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-28789175

RESUMEN

Conventional micropore membranes based size sorting have been widely applied for single-cell analysis. However, only a single filtering size can be achieved and the clogging issue cannot be completely avoided. Here, we propose a novel arch-like microsorter capable of multimodal (high-, band- and low-capture mode) sorting of particles. The target particles can pass through the front filter and are then trapped by the back filter, while the non-target particles can bypass or pass through the microsorter. This 3D arch-like microstructures are fabricated inside a microchannel by femtosecond laser parallel multifocal scanning. The designed architecture allows for particles isolation free of clogging over 20 minutes. Finally, as a proof of concept demonstration, SUM159 breast cancer cells are successfully separated from whole blood.

12.
Chemosphere ; 358: 142275, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38719125

RESUMEN

Microplastics (MPs) are widespread environmental contaminants that have been detected in animals and humans. However, their toxic effects on terrestrial mammals and the underlying mechanisms are still not well understood. Herein, we explored the role of gut microbiota in mediating the toxicity of micro- and nano-sized polystyrene plastics (PS-MPs/PS-NPs) using an antibiotic depleted mice model. The results showed that PS-MPs and PS-NPs exposure disrupted the composition and structure of the gut microbiota. Specifically, these particles led to an increase in pathogenic Esherichia-shigella, while depleting probiotics such as Akkermansia and Lactobacillus. Comparatively, PS-NPs particles had more pronounced effect, leading to obviously shifted the colon transcriptional profiles characterized by inducing the enrichment of colon metabolism and immune-related pathways (i.e., upregulated in genes like udgh, ugt1a1, ugt1a6a, ugt1a7c and ugt2b34). Additionally, both PS-MPs and PS-NPs induced oxidative stress, gut-liver damage and systemic inflammation in mice. Mechanistically, we confirmed that PS particles disturbed gut microbiota, activating TLR2-My88-NF-κB pathway to trigger the release of inflammatory cytokine IL-1ß and TNF-α. The damage and inflammation caused by both size of PS particles was alleviated when the gut microbiota was depleted. In conclusion, our findings deepen the understanding of the molecule mechanisms by which gut microbiota mediate the toxicity of PS particles, informing health implications of MPs pollution.


Asunto(s)
Microbioma Gastrointestinal , Microplásticos , Poliestirenos , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Poliestirenos/toxicidad , Ratones , Microplásticos/toxicidad , Nanopartículas/toxicidad , Nanopartículas/química , Estrés Oxidativo/efectos de los fármacos , Tamaño de la Partícula , Inflamación/inducido químicamente , Contaminantes Ambientales/toxicidad , Masculino , FN-kappa B/metabolismo
13.
J Hazard Mater ; 470: 134169, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38565022

RESUMEN

Microplastic (MP) pollution poses a significant threat to marine ecosystem and seafood safety. However, comprehensive and comparable assessments of MP profiles and their ecological and health in Chinese farming oysters are lacking. This study utilized laser infrared imaging spectrometer (LDIR) to quantify MPs in oysters and its farming seawater at 18 sites along Chinese coastlines. Results revealed a total of 3492 MPs in farmed oysters and seawater, representing 34 MP types, with 20-100 µm MP fragments being the dominant. Polyurethane (PU) emerged as the predominant MP type in oysters, while polysulfones were more commonly detected in seawater. Notably, oysters from the Bohai Sea exhibited a higher abundance of MPs (13.62 ± 2.02 items/g) and estimated daily microplastic intake (EDI, 2.14 ± 0.26 items/g/kg·bw/day), indicating a greater potential health risk in the area. Meanwhile, seawater from the Yellow Sea displayed a higher level (193.0 ± 110.7 items/L), indicating a greater ecological risk in this region. Given the pervasiveness and abundance of PU and its high correlation with other MP types, we proposed PU as a promising indicator for monitoring and assessing the risk MP pollution in mariculture in China. These findings provide valuable insights into the extent and characteristics of MP pollution in farmed oysters and seawater in China.


Asunto(s)
Acuicultura , Monitoreo del Ambiente , Microplásticos , Ostreidae , Agua de Mar , Contaminantes Químicos del Agua , Animales , Agua de Mar/análisis , China , Contaminantes Químicos del Agua/análisis , Ostreidae/química , Microplásticos/análisis , Medición de Riesgo
14.
Water Res ; 256: 121584, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38598950

RESUMEN

Antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) are prevalent in various environments on livestock farms, including livestock waste, soil, and groundwater. Contamination of groundwater by ARB and ARGs in livestock farms is a growing concern as it may have potentially huge risks to human health. However, the source of groundwater-borne ARB and ARGs in animal farms remains largely unknown. In this study, different types of samples including groundwater and its potential contamination sources from aboveground (pig feces, wastewater, and soil) from both working and abandoned swine feedlots in southern China were collected and subjected to metagenomic sequencing and ARB isolation. The source tracking based on metagenomic analysis revealed that 56-95 % of ARGs in groundwater was attributable to aboveground sources. Using metagenomic assembly, we found that 45 ARGs predominantly conferring resistance to aminoglycosides, sulfonamides, and tetracyclines could be transferred from the aboveground sources to groundwater, mostly through plasmid-mediated horizontal gene transfer. Furthermore, the full-length nucleotide sequences of sul1, tetA, and TEM-1 detected in ARB isolates exhibited the close evolutionary relationships between aboveground sources and groundwater. Some isolated strains of antibiotic-resistant Pseudomonas spp. from aboveground sources and groundwater had the high similarity (average nucleotide identity > 99 %). Notably, the groundwater-borne ARGs were identified as mainly carried by bacterial pathogens, potentially posing risks to human and animal health. Overall, this study underscores the dissemination of ARGs from aboveground sources to groundwater in animal farms and associated risks.


Asunto(s)
Farmacorresistencia Microbiana , Agua Subterránea , Ganado , Agua Subterránea/microbiología , Animales , Farmacorresistencia Microbiana/genética , Granjas , Porcinos , China , Antibacterianos/farmacología , Genes Bacterianos , Aguas Residuales/microbiología , Farmacorresistencia Bacteriana/genética
15.
J Imaging ; 9(8)2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37623694

RESUMEN

Thangka images exhibit a high level of diversity and richness, and the existing deep learning-based image captioning methods generate poor accuracy and richness of Chinese captions for Thangka images. To address this issue, this paper proposes a Semantic Concept Prompt and Multimodal Feature Optimization network (SCAMF-Net). The Semantic Concept Prompt (SCP) module is introduced in the text encoding stage to obtain more semantic information about the Thangka by introducing contextual prompts, thus enhancing the richness of the description content. The Multimodal Feature Optimization (MFO) module is proposed to optimize the correlation between Thangka images and text. This module enhances the correlation between the image features and text features of the Thangka through the Captioner and Filter to more accurately describe the visual concept features of the Thangka. The experimental results demonstrate that our proposed method outperforms baseline models on the Thangka dataset in terms of BLEU-4, METEOR, ROUGE, CIDEr, and SPICE by 8.7%, 7.9%, 8.2%, 76.6%, and 5.7%, respectively. Furthermore, this method also exhibits superior performance compared to the state-of-the-art methods on the public MSCOCO dataset.

16.
Bioresour Technol ; 387: 129673, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37579863

RESUMEN

Contamination of the environment with large amounts of residual oxytetracycline (OTC) and the corresponding resistance genes poses a potential threat to natural ecosystems and human health. In this study, an effective OTC-degrading strain, identified as Achromobacter denitrificans OTC-F, was isolated from activated sludge. In the degradation experiment, the degradation rates of OTC in the degradation systems with and without biochar addition were 95.01-100% and 73.72-99.66%, respectively. Biochar promotes the biodegradation of OTC, particularly under extreme environmental conditions. Toxicity evaluation experiments showed that biochar reduced biotoxicity and increased the proportion of living cells by 17.36%. Additionally, biochar increased the activity of antioxidant enzymes by 34.1-91.0%. Metabolomic analysis revealed that biochar promoted the secretion of antioxidant substances such as glutathione and tetrahydrofolate, which effectively reduced oxidative stress induced by OTC. This study revealed the mechanism at the molecular level and provided new strategies for the bioremediation of OTC in the environment.


Asunto(s)
Achromobacter denitrificans , Oxitetraciclina , Humanos , Oxitetraciclina/metabolismo , Achromobacter denitrificans/metabolismo , Ecosistema , Antioxidantes
17.
Sci Total Environ ; 860: 160478, 2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36574551

RESUMEN

The contradiction between population growth and soil degradation has been increasingly prominent, such that novel fertilizers (e.g., biochar and microbial fertilizers) should be urgently developed. Biochar is a promising fertilizer carrier for microbial fertilizers due to its porous structure. However, the preparation and mechanisms of the effects of biochar-based microbial fertilizers have been rarely investigated. In this study, biochar, Bacillus, and exogenous N-P-K fertilizers served as the raw materials to prepare biochar-based microbial fertilizers (BCMFs) by optimizing the preparation methods and the process parameters. Moreover, the release patterns of N-P-K were analyzed. A pot experiment was performed on pakchoi to examine the effect of the BCMFs and explore its synergistic effect on soil fertility. The results of this study indicated that adsorption by biochar maintained bacterial activity, whereas the granulation process reduced bacterial activity. The adsorption-granulation process increased the content of total nitrogen and organic matter in the soil while enhancing the slow-release effect of the BCMFs. The Elovich model was capable of describing the nitrogen release of the BCMFs, including the diffusion and chemical processes. As indicated by the result of the column leaching experiment, the BCMFs stopped nutrient leaching more significantly than the conventional fertilizers (CF), especially in stopping N and P leaching. The use of the BCMFs improved the available soil nutrients and soil quality while enhancing the abundance of bacteria correlated with carbon and nitrogen metabolism in the soil. Moreover, a 20 % reduction in the use of the BCMFs did not significantly affect the soil available N and P and the growth status of pakchoi. The result of redundancy analysis indicated that the cation exchange capacity (CEC), NH4+-N, NO3--N, ß-glucosidase (BG), urease (URE), and alkaline phosphatase (AlkP) were the six critical environmental factors for the microbial community structure and could explain 94.8 % of the variance. The BCMFs up-regulated the levels of the above six factors, especially CEC and BG, thus improving the soil quality and enhancing the soil fertility.


Asunto(s)
Fertilizantes , Suelo , Suelo/química , Fertilizantes/análisis , Carbón Orgánico/química , Nitrógeno/análisis , Bacterias , Nutrientes/análisis , Microbiología del Suelo
18.
Pathol Res Pract ; 245: 154463, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37086631

RESUMEN

Hypoxia contributes to the tumorigenesis and metastasis of the tumor. However, the detailed mechanisms underlying hypoxia and kidney renal clear cell carcinoma (KIRC) development and progression remain unclear. Here, we investigated the role of the system HIG1 hypoxia inducible domain family member 1 A (HIGD1A) in the proliferation and metastasis of KIRC and elucidated the underlying molecular mechanisms. The expression of HIGD1A is significantly downregulated in KIRC due to promoter hypermethylation. HIGD1A could serve as a valuable diagnostic biomarker in KIRC. In addition, ectopic overexpression of HIGD1A significantly suppressed the growth and invasive capacity of KIRC cells in vitro under normal glucose conditions. Interestingly, the suppressive efficacy in invasion is much more significant when depleted glucose, but not in proliferation. Furthermore, mRNA expression of HIGD1A positively correlates with CDH1 and EPCAM, while negatively correlated with VIM and SPARC, indicating that HIGD1A impedes invasion of KIRC by regulating epithelial-mesenchymal transition (EMT). Our data suggest that HIGD1A is a potential diagnostic biomarker and tumor suppressor in KIRC.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Biomarcadores , Carcinoma de Células Renales/patología , ADN , Riñón/patología , Neoplasias Renales/patología
19.
Comput Intell Neurosci ; 2022: 7636705, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35571693

RESUMEN

A single model is often used to classify text data, but the generalization effect of a single model on text data sets is poor. To improve the model classification accuracy, a method is proposed that is based on a deep neural network (DNN), recurrent neural network (RNN), and convolutional neural network (CNN) and integrates multiple models trained by a deep learning network architecture to obtain a strong text classifier. Additionally, to increase the flexibility and accuracy of the model, various optimizer algorithms are used to train data sets. Moreover, to reduce the interference in the classification results caused by stop words in the text data, data preprocessing and text feature vector representation are used before training the model to improve its classification accuracy. The final experimental results show that the proposed model fusion method can achieve not only improved classification accuracy but also good classification effects on a variety of data sets.


Asunto(s)
Aprendizaje Profundo , Algoritmos , Redes Neurales de la Computación
20.
Comput Intell Neurosci ; 2022: 4027667, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36199965

RESUMEN

During the operation of navigation satellites, errors in the broadcast ephemeris orbits are caused by the influence of ingress factors and other factors. To address this phenomenon, this paper examines the use of the computational intelligence (CI) methods to implement track correction and to develop an optimized BP neural network model based on an improved particle swarm algorithm. The model improves the inertia weights and learning factor parameters of the particle swarm optimization (PSO) algorithm to improve the global optimization capability and accelerate the convergence speed. The improved PSO (IPSO) algorithm is used to perform a global optimization search for the hyperparameters of the BP neural network, and then the neural network model is trained by broadcast ephemeris Keplerian root number and regression parameters. The model is validated using the broadcast ephemeris data of the BDS-3 MEO and IGSO satellites, and the mean square error correction rate of multiple satellites with different correction models shows that the error correction rate of the IPSO-BPNN model can reach 70.2-84% and the error correction rate can be improved by 14.2-56.8% compared with the PSO-BPNN model. The proposed algorithm provides an important reference for BDS-3 and other global navigation satellite systems for improving the accuracy of satellite orbit determination.


Asunto(s)
Redes Neurales de la Computación , Comunicaciones por Satélite , Algoritmos , Inteligencia Artificial
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