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1.
Environ Pollut ; 352: 124062, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38701963

RESUMO

The leaching process of uranium tailings is a typical water-rock interaction. The release of 226Ra from uranium tailings depends on the nuclides outside the intrinsic properties of uranium tailings on the one hand, and is influenced by the water medium on the other. In this paper, a uranium tailings repository in southern China was used as a research object, and uranium tailings at different depths were collected by drilling samples and mixed to analyze the 226Ra occurrence states. Static dissolution leaching experiments of 226Ra under different pH conditions, solid-liquid ratio conditions, and ionic strength conditions were carried out, and the adsorption and desorption behaviours of 226Ra in five representative stratigraphic media were investigated. The results show that 226Ra has a strong adsorption capacity in representative strata, with adsorption distribution coefficient Kd values ranging from 1.07E+02 to 1.29E+03 (mL/g) and desorption distribution coefficients ranging from 4.97E+02 to 2.71E+03 (mL/g), but the adsorption is reversible. The 226Ra in uranium tailings exists mainly in the residual and water-soluble states, and the release of 226Ra from uranium tailings under different conditions is mainly from the water-soluble and exchangeable state fractions. Low pH conditions, low solid-liquid ratio conditions and high ionic strength conditions are favourable to the release of 226Ra from uranium tailings, so the release of 226Ra from uranium tailings can be reduced by means of adjusting the pH in the tailings and setting up a water barrier. The results of this research have important guiding significance for the management of existing uranium tailings ponds and the control of 226Ra migration in groundwater, which is conducive to guaranteeing the long-term safety, stability and sustainability of uranium mining sites.


Assuntos
Rádio (Elemento) , Urânio , Urânio/química , Adsorção , Rádio (Elemento)/análise , Rádio (Elemento)/química , China , Poluentes Radioativos do Solo/análise , Monitoramento de Radiação , Mineração , Poluentes Radioativos da Água/química , Poluentes Radioativos da Água/análise
2.
Vet Microbiol ; 290: 109969, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38211362

RESUMO

Emerging evidence confirms beneficial properties of probiotics in promoting growth and immunity of farmed chicken. However, the molecular mechanisms underlying the host-microbiome interactions mediated by probiotics are not fully understood. In this study, the internal mechanisms of Lacticaseibacillus chiayiensis-mediated host-microbiome interactions and to elucidate how it promotes host growth were investigated by additional supplementation with L. chiayiensis. We conducted experiments, including intestinal cytokines, digestive enzymes test, intestinal microbiome, metabolome and transcriptome analysis. The results showed that chickens fed L. chiayiensis exhibited higher body weight gain and digestive enzyme activity, and lower pro-inflammatory cytokines, compared to controls. Microbiota sequencing analysis showed that the gut microbiota structure was reshaped with L. chiayiensis supplementation. Specifically, Lactobacillus and Escherichia increased in abundance and Enterococcus, Lactococcus, Corynebacterium, Weissella and Gallicola decreased. In addition, the bacterial community diversity was significantly increased compared to controls. Metabolomic and transcriptomic analyses revealed that higher bile acids and N-acyl amides concentrations and lower carbohydrates concentrations in L. chiayiensis-fed chickens. Meanwhile, the expression of genes related to nutrient transport and absorption in the intestine was upregulated, which reflected the enhanced digestion and absorption of nutrients in chickens supplemented with L. chiayiensis. Moreover, supplementation of L. chiayiensis down-regulated genes involved in inflammation-related, mainly involved in NF-κB signaling pathway and MHC-II mediated antigen presentation process. Cumulatively, these findings highlight that host-microbiota crosstalk enhances the host growth phenotype in two ways: by enhancing bile acid metabolism and digestive enzyme activity, and reducing the occurrence of intestinal inflammation to promote nutrient absorption and maintain intestinal health. This provides a basis for the application of LAB as an alternative to antibiotics in animal husbandry.


Assuntos
Microbioma Gastrointestinal , Microbiota , Animais , Microbioma Gastrointestinal/genética , Galinhas , Lactobacillus , Inflamação/veterinária , Citocinas , Lacticaseibacillus
3.
J Environ Manage ; 353: 120207, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38281428

RESUMO

The release of uranium from uranium tailings into the aqueous environment is a complex process controlled by a series of interacting geochemical reactions. In this paper, uranium tailings from a uranium tailings pond in southern China were collected at different depths by means of borehole sampling and mixed to analyze the fugacity state of U. Static leaching experiments of U at different pH, oxidant concentration and solid-to-liquid ratios and dynamic leaching experiments of U at different pH were carried out, and the adsorption and desorption behaviour of U in five representative stratigraphic media were investigated. The results show that U is mainly present in the residue state in uranium tailings, that U release is strong in the lower pH range, that the leached U is mainly in the form of U(VI), mainly from the water-soluble, Fe/Mn oxides and exchangeable fraction of uranium tailings, and that the reduction in U leaching at higher pH is mainly due to the combined effect of precipitation formation and larger particle size of platelets in uranium tailings. Experiments with different oxidant concentrations and solid-liquid ratios showed that the oxygen-enriched state and low solid-liquid ratios were favorable for the leaching of U from uranium tailings. Adsorption and desorption experiments show that U is weakly adsorbed in representative strata, reversibly adsorbed, and that U is highly migratory in groundwater. The present research results have important guiding significance for the management of existing uranium tailings ponds and the control of U migration in groundwater, which is conducive to ensuring the long-term safety, stability and sustainability of uranium mining sites.


Assuntos
Poluentes Radioativos do Solo , Urânio , Poluentes Radioativos da Água , Urânio/análise , Adsorção , Poluentes Radioativos do Solo/análise , Poluentes Radioativos da Água/análise , Água , Oxidantes
4.
J Dairy Sci ; 107(3): 1355-1369, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37776999

RESUMO

It is desirable to obtain high levels of viable Lacticaseibacillus paracasei, a widely used food probiotic whose antibacterial activity and potential application in milk remain largely uninvestigated. Here, we isolated and purified the L. paracasei strain XLK 401 from food-grade blueberry ferments and found that it exhibited strong antibacterial activity against both gram-positive and gram-negative foodborne pathogens, including Staphylococcus aureus, Salmonella paratyphi B, Escherichia coli O157, and Shigella flexneri. Then, we applied alternating tangential flow (ATF) technology to produce viable L. paracasei XLK 401 cells and its cell-free supernatant (CFS). Compared with the conventional fed-batch method, 22 h of ATF-based processing markedly increased the number of viable cells of L. paracasei XLK 401 to 12.14 ± 0.13 log cfu/mL. Additionally, the CFS exhibited good thermal stability and pH tolerance, inhibiting biofilm formation in the abovementioned foodborne pathogens. According to liquid chromatography-mass spectrometry analysis, organic acids were the main antibacterial components of XLK 401 CFS, accounting for its inhibition activity. Moreover, the CFS of L. paracasei XLK 401 effectively inhibited the growth of multidrug-resistant gram-positive Staph. aureus and gram-negative E. coli O157 pathogens in milk, and caused a reduction in the pathogenic cell counts by 6 to 7 log cfu/mL compared with untreated control, thus considerably maintaining the safety of milk samples. For the first time to our knowledge, ATF-based technology was employed to obtain viable L. paracasei on a large scale, and its CFS could serve as a broad-spectrum biopreservative for potential application against foodborne pathogens in milk products.


Assuntos
Escherichia coli O157 , Lacticaseibacillus paracasei , Animais , Leite , Antibacterianos/farmacologia , Contagem de Células/veterinária
5.
Microorganisms ; 11(9)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37763985

RESUMO

Lacticaseibacillus paracasei, serves as a growth promoter used in the poultry industry, contributeing to broiler development. However, practical studies are needed to determine the probiotic potential and growth-promoting effects of specific L. paracasei strains. This study aims to determine whether L. paracasei XLK401 influences broiler chicken growth and the mechanisms involved. Notably, we identified several bile salt and acid tolerance-related genes (Asp23, atpD, atpA, atpH, and atpF) in L. paracasei XLK401. This bacterium demonstrates robust probiotic properties under acidic conditions (pH 2.0) and 0.3% bile salt conditions. It also contains a variety of antioxidant-related genes (trxA, trxB, and tpx), carbohydrate-related genes, gene-encoding glycosidases (e.g., GH and GT), and three clusters of genes associated with antimicrobial compounds. Supplementation with L. paracasei XLK401 significantly increased the body weight of the chicks. In addition, it significantly increased hepatic antioxidant enzyme activities (GSH-Px, SOD, and T-AOC) while significantly decreasing the levels of oxidative damage factors and inflammatory factors (MDA and IL-6), resulting in improved chick health. Improvements in body weight and health status were associated with significant increases in α-amylase activity and the remodeling of the host gut microbiota by L. paracasei XLK401. Among them, actinobacteria abundance in chicken intestines after feeding them L. paracasei XLK401 was significantly decreased, Bifidobacterium sp. abundance was also significantly decreased, and Subdoligranulum sp. abundance was significantly increased. This suggests that L. paracasei XLK401 can regulate the abundance of certain bacteria without changing the overall microbial structure. In addition, in the correlation analysis, Subdoligranulums sp. were positively correlated with SOD and negatively correlated with IL-1ß and MDA. Overall, our study demonstrates that L. paracasei XLK401 effectively promotes healthy chick growth. This is made possible by the modulation of gut microbe abundance and the underlying probiotic effect of L. paracasei XLK401. Based on these findings, we postulate L. paracasei XLK401 as a potential efficient growth promoter in broiler farming.

6.
Antibiotics (Basel) ; 12(9)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37760653

RESUMO

The growing issue of antibiotic resistance has restrained the utilization of antibiotics as growth enhancers in the poultry industry. Probiotics are candidates for replacing antibiotics in the poultry industry. However, probiotics are strain-specific and their efficacy needs to be investigated before applying them. The aim of this study was to assess the positive effects of Lacticaseibacillus chiayiensis AACE3 on the health and gut microbiota of Nandan Yao chicks. The results showed that compared with the blank control (NC) and aureomycin (PC) groups, L. chiayiensis AACE3 increased final body weight (BW), villus height and improved the ratio of villus height to crypt depth in chicken jejunal tissues. L. chiayiensis AACE3 also increased the activity of hepatic antioxidant enzymes (SOD, CAT and T-AOC) and reduced hepatic oxidative damage (MDA). Furthermore, compared to NC, L. chiayiensis AACE3, the activity of intestinal digestive enzymes (i.e., α-amylase, lipase and trypsin) was increased. L. chiayiensis AACE3 upregulated the production of IgA and IgG and downregulated the production of IL-6, IL-1ß and TNF-α in chicken serum. Moreover, supplementation of L. chiayiensis AACE3 enhances the diversity of gut microbes. At the phylum level, the abundance of Actinobacteriota and Proteobacteria decreased with L. chiayiensis AACE3 supplementation, while the abundance of Verrucomicrobiota and Bacteroidetes increased. At the genus level, there was an increase in the abundance of potential probiotics Akkermansia, Romboutsia, Subdoligranulum, and Lactobacillus. This study confirms that L. chiayiensis AACE3 is an excellent feed additive as an alternative to aureomycin and offers various advantages for the healthy growth of chickens during the brooding period by positively affecting their gut microbiome.

7.
J Environ Radioact ; 270: 107300, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37757656

RESUMO

A large number of radionuclides remain in uranium tailings, and U, 226Ra and 210Pb leach out with water chemistry, causing potential radioactive contamination to the surrounding environment. In this paper, uranium tailings from a uranium tailings pond in southern China were collected at different depths by means of borehole sampling, mixed and homogenised, and analysed for mineral and chemical composition, microscopic morphology, U, 226Ra and 210Pb fugacity, static leaching and dynamic leaching of U, 226Ra and 210Pb in uranium tailings at different pH conditions. The variation of U, 226Ra and 210Pb concentrations in the leachate under different pH conditions with time was obtained, and the leaching mechanism was analysed. The results showed that the uranium tailings were dominated by quartz, plagioclase and other minerals, of which SiO2 and Al2O3 accounted for 65.45% and 13.32% respectively, and U, 226Ra and 210Pb were mainly present in the residue form. The results of the static leaching experiments show that pH mainly influences the leaching of U, 226Ra and 210Pb by changing their chemical forms and the particle properties of the tailings, and that the lower the pH the more favourable the leaching. The results of dynamic leaching experiments during the experimental cycle showed that the leaching concentration and cumulative release of U, 226Ra and 210Pb in the leach solution were greater at lower pH conditions than at higher pH conditions, and the leaching of U, 226Ra and 210Pb at different pH conditions was mainly from the water-soluble and exchangeable states. The present research results are of great significance for the environmental risk management and control of radioactive contamination in existing uranium tailings ponds, and are conducive to ensuring the long-term safety, stability and sustainability of uranium mining sites.


Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo , Urânio , Urânio/análise , Chumbo/análise , Dióxido de Silício/análise , Poluentes Radioativos do Solo/análise , Minerais/análise , Concentração de Íons de Hidrogênio , Água
8.
Front Microbiol ; 14: 1168378, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37275148

RESUMO

Numerous different species of LAB are used in different fields due to their unique characteristics. However, Lacticaseibacillus chiayiensis, a newly established species in 2018, has limited microorganism resources, and lacks comprehensive evaluations of its properties. In this study, L. chiayiensis AACE3, isolated from fermented blueberry, was evaluated by genomic analysis and in vitro assays of the properties. The genome identified genes associated with biofilm formation (luxS, ccpA, brpA), resistance to oxidative stress (tpx, trxA, trxB, hslO), tolerance to acidic conditions (dltA, dltC), resistance to unfavorable osmotic pressure (opuBB, gbuA, gbuB, gbuC), and adhesion (luxS, dltA, dltC). The AACE3 showed 112 unique genes, relative to the other three L. chiayiensis strains. Among them, the presence of genes such as clpP, pepO, and feoA suggests a possible advantage of AACE3 over other L. chiayiensis in terms of environmental adaptation. In vitro evaluation of the properties revealed that AACE3 had robust antibacterial activity against eight common pathogens: Streptococcus agalactiae, Staphylococcus aureus, Escherichia coli, Salmonella enteritidis, Salmonella choleraesuis, Shigella flexneri, Pseudomonas aeruginosa, and Klebsiella pneumoniae. In addition, AACE3 showed more than 80% survival rate in all tests simulating gastrointestinal fluid, and it exhibited high antioxidant capacity. Interestingly, the cell culture supernatant was superior to intact organisms and ultrasonically crushed bacterial extracts in all tests of antioxidant capacity. These results suggested that the antioxidant capacity may originate from certain metabolites and extracellular enzymes produced by AACE3. Moreover, AACE3 was a moderate biofilm producer due to the self-agglomeration effect. Taken together, L. chiayiensis AACE3 appears to be a candidate strain for combating the growing incidence of pathogen infections and antioxidant production.

9.
J Hazard Mater ; 458: 131594, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37330373

RESUMO

The mechanisms underlying the toxicity of environmental stress are unclear for marine macrobenthos. Copper/Cu has posed the most serious threats to amphioxus, an ancient and model benthic cephalochordate. Herein, a dynamic change in the physiological parameters (GR, SOD, ATP, and MDA) was detected with ROS accumulation in Branchiostoma belcheri exposed to 0.3 mg·L-1 Cu. Transcriptomes and microRNAomes of B. belcheri were generated to investigate the molecular mechanisms by which this amphioxus copes with Cu exposure. Time-specific genes identified at different time points after exposure were involved in the stimulus and immune response, detoxification and ionic homeostasis, aging and the nervous system, sequentially, with prolongation of exposure time, forming a dynamic process of molecular response to Cu stress. In total, 57 differentially expressed miRNAs were identified under Cu stress. Transcriptomics-miRNAomics analyses indicate that these miRNAs targeted genes associated with many key biological processes such as xenobiotics degradation, oxidative stress, and energy metabolism. The constructed miRNA-mRNA-pathway network uncovered a broad post-transcriptional regulatory mechanism in B. belcheri to cope with Cu stress. Overall, this integrated analyses show that enhanced defense response, accelerated ROS elimination, and repressed ATP production constitute a comprehensive strategy to cope with Cu toxicity in the ancient macrobenthos.


Assuntos
Anfioxos , MicroRNAs , Animais , Transcriptoma , Cobre/toxicidade , Cobre/metabolismo , Espécies Reativas de Oxigênio/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Trifosfato de Adenosina/metabolismo
10.
Int J Mol Med ; 52(1)2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37203409

RESUMO

Histidine triad nucleotide­binding protein (HINT) belongs to the histidine triad protein family. Recent studies have demonstrated that HINT1 and HINT2 both play a pivotal role in cancer growth. However, the functions of HINT3 in various types of cancer, including breast cancer (BRCA), have not yet been fully elucidated. In the present study, the role of HINT3 in BRCA was investigated. Based on The Cancer Genome Atlas and reverse transcription­quantitative PCR analyses, HINT3 was found to be decreased in BRCA tissues. In vitro, HINT3 knockdown promoted the proliferation and colony formation of, and 5­ethynyl­2'­deoxyuridine incorporation in MCF­7 and MDA­MB­231 BRCA cells. By contrast, HINT3 overexpression suppressed DNA synthesis and the proliferation of both cell lines. Apoptosis was also found to be modulated by HINT3. In vivo, HINT3 ectopic expression attenuated the tumorigenesis of MDA­MB­231 and MCF­7 cells in a mouse tumor xenograft model. Furthermore, HINT3 silencing or overexpression also enhanced or inhibited, respectively, the migratory capacity of the MCF­7 and MDA­MB­231 cells. Finally, HINT3 upregulated phosphatase and tensin homolog (PTEN) at the transcriptional level, which resulted in the inactivation of AKT/mammalian target of rapamycin (mTOR) signaling both in vitro and in vivo. Taken together, the present study demonstrates that HINT3 inhibits the activation of the PTEN/AKT/mTOR signaling pathway, and suppresses the proliferation, growth, migration and tumor development of MCF­7 and MDA­MB­231 BRCA cells.


Assuntos
Neoplasias da Mama , Proteínas Proto-Oncogênicas c-akt , Animais , Feminino , Humanos , Camundongos , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Carcinogênese/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Transformação Celular Neoplásica , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Transdução de Sinais/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Ativação Transcricional
11.
Front Microbiol ; 14: 1120263, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37007532

RESUMO

Lactic acid bacteria are generally regarded as alternatives to antibiotics in livestock and poultry farming, especially Lactobacillus strains, which are safe and have probiotic potential. Although Lactobacillus salivarius has long been proposed to be a probiotic, the understanding of the roles of this species is still in its infancy. Here, a strain of L. salivarius CGMCC20700 isolated from the intestinal mucosa of Yunnan black-bone chicken broilers was investigated in the context of its safety and probiotic characteristics by whole-genome sequencing in parallel with phenotypic analysis. Whole-genome sequencing results showed that L. salivarius CGMCC20700 has a single scaffold of 1,737,577 bp with an average guanine-to-cytosine (GC) ratio of 33.51% and 1,757 protein-coding genes. The annotation of Clusters of Orthologous Groups (COG) classified the predicted proteins from the assembled genome as possessing cellular, metabolic, and information-related functions. Sequences related to risk assessment, such as antibiotic resistance and virulence genes, were identified, and the strain was further confirmed as safe according to the results of antibiotic resistance, hemolytic, and acute oral toxicology tests. Two gene clusters of antibacterial compounds and broad-spectrum antimicrobial activity were identified using genome mining tools and antibacterial spectrum tests. Stress resistance genes, active stressor removal genes, and adhesion related genes that were identified and examined with various phenotypic assays (such as stress tolerance tests in acids and bile salts and auto aggregation and hydrophobicity assays). The strain showed a high survival rate in the presence of bile salts and under acidic conditions and exhibited significant auto aggregation capacity and hydrophobicity. Overall, L. salivarius CGMCC20700 demonstrated excellent safety and probiotic potential at both the genomic and physiological levels and can be considered an appropriate candidate probiotic for livestock and poultry farming.

12.
Curr Res Food Sci ; 6: 100484, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37033741

RESUMO

Foodborne pathogens and their biofilms pose a risk to human health through food chain. However, the bacteriocin resources combating this threat are still limited. Here, Lacticaseibacillus rhamnosus, one of the most used probiotics in food industry, was prepared on a large scale using alternating tangential flow (ATF) perfusion-based technology. Compared to the conventional fed-batch approach, ATF perfusion remarkably increased the viable cells of L. rhamnosus CLK 101 to 11.93 ± 0.14 log CFU/mL. Based on obtained viable cells, we purified and characterized a novel bacteriocin CLK_01 with a broad spectrum of activity against both Gram-positive and Gram-negative foodborne pathogens. LC-MS/MS analysis revealed that CLK_01 has a molecular mass of 701.49 Da and a hydrophobic amino acid composition of I-K-K-V-T-I. As a novel bacteriocin, CLK_01 showed high thermal stability and acid-base tolerance over 25-121 °C and pH 2-10. It significantly reduced cell viability of bacterial pathogens (p < 0.001), and strongly inhibited their biofilm formation. Scanning electron microscopy demonstrated deformation of pathogenic cells caused by CLK_01, leading to cytoplasmic content leakage and bacterial death. Summarily, we employed ATF perfusion to obtain viable L. rhamnosus, and presented that bacteriocin CLK_01 could serve as a promising biopreservative for controlling foodborne pathogenic bacteria and their biofilms.

13.
Nucleic Acids Res ; 51(7): 3150-3165, 2023 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-36869674

RESUMO

DNA double-strand breaks (DSBs) are functionally linked to genomic instability in spermatocytes and to male infertility. The heavy metal cadmium (Cd) is known to induce DNA damage in spermatocytes by unknown mechanisms. Here, we showed that Cd ions impaired the canonical non-homologous end-joining (NHEJ) repair pathway, but not the homologous recombination (HR) repair pathway, through stimulation of Ser2056 and Thr2609 phosphorylation of DNA-PKcs at DSB sites. Hyper-phosphorylation of DNA-PKcs led to its premature dissociation from DNA ends and the Ku complex, preventing recruitment of processing enzymes and further ligation of DNA ends. Specifically, this cascade was initiated by the loss of PP5 phosphatase activity, which results from the dissociation of PP5 from its activating ions (Mn), that is antagonized by Cd ions through a competitive mechanism. In accordance, in a mouse model Cd-induced genomic instability and consequential male reproductive dysfunction were effectively reversed by a high dosage of Mn ions. Together, our findings corroborate a protein phosphorylation-mediated genomic instability pathway in spermatocytes that is triggered by exchange of heavy metal ions.


Assuntos
Cádmio , Instabilidade Genômica , Infertilidade Masculina , Espermatócitos , Animais , Humanos , Masculino , Camundongos , Cádmio/toxicidade , DNA/metabolismo , Reparo do DNA por Junção de Extremidades , Reparo do DNA , Instabilidade Genômica/efeitos dos fármacos , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Íons/metabolismo , Fosforilação , Reparo de DNA por Recombinação , Espermatócitos/efeitos dos fármacos
14.
Toxics ; 11(2)2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36850999

RESUMO

In this study, a column experiment was employed to evaluate the nuclide migration behavior in the surrounding rock medium of a near-surface disposal site in China and to investigate the advection-dispersion behavior of tritium (H-3) and plutonium-238 (Pu-238) in highly weathered argillaceous shale. A reasonable numerical model was selected to fit the experimental breakthrough curves (BTCs) and to obtain the relevant migration parameters. The results show the following: (1) the internal structure of the highly weathered argillaceous shale exhibited heterogeneity, and the nuclide migration BTC showed characteristics of a "curve peak moving forward" and a "tail curve trailing"; (2) compared with other models, the stream tube mode could better fit the BTCs and obtain the average dispersion coefficient , average distribution coefficient , and other parameters; (3) compared to the results of the batch experiment, the distribution coefficient Kd obtained from the column experiment was smaller than that obtained from the batch experiment, which is speculated to be due to the influence of contact time and the contact area between the nuclide and the medium.

15.
Meat Sci ; 196: 109045, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36434981

RESUMO

Antibacterial activity and mechanism of action of bacteriocins against bacteria that cause pork contamination remain unclear. Here, antibacterial activity of bacteriocin LFX01 against two important indicator strains (i.e., Staphylococcus aureus and Escherichia coli) and its mechanism of action were investigated. The results showed antibacterial activity of LFX01 against growth and biofilm formation of S. aureus_26 (strain 2612:1606BL1486) and E. coli_02 (strain CMCC(B)44102). Additionally, the results demonstrated that LFX01 could decrease cell metabolic activity, disrupt cell membrane permeability and integrity, and trigger leakage of intracellular contents (e.g., K+, ATP, and lactic dehydrogenase). Furthermore, gel retardation showed that LFX01 could bind to the genomic DNA of indicator strains, disrupting DNA structure. These results uncovered mechanism of action of LFX01 against indicator strains from physiological and phenotypic levels. When applied to the surface of fresh pork models, the antibacterial activity of LFX01 against indicator strains was further confirmed. These findings suggested that LFX01 could be a potential pork preservative for controlling foodborne pathogens.


Assuntos
Bacteriocinas , Carne de Porco , Carne Vermelha , Suínos , Animais , Staphylococcus aureus , Escherichia coli , Bacteriocinas/farmacologia , Antibacterianos/farmacologia
16.
Front Plant Sci ; 14: 1309038, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38264031

RESUMO

Gastrodia elata Blume, a fully mycoheterotrophic perennial plant of the family Orchidaceae, is a traditional Chinese herb with medicinal and edible value. Interestingly, G. elata requires symbiotic relationships with Mycena and Armillaria strains for seed germination and plant growth, respectively. However, there is no comprehensive summary of the symbiotic mechanism between fungi and G. elata. Here, the colonization and digestion of hyphae, the bidirectional exchange of nutrients, the adaptation of fungi and G. elata to symbiosis, and the role of microorganisms and secondary metabolites in the symbiotic relationship between fungi and G. elata are summarized. We comprehensively and deeply analyzed the mechanism of symbiosis between G. elata and fungi from three perspectives: morphology, nutrition, and molecules. The aim of this review was to enrich the understanding of the mutualistic symbiosis mechanisms between plants and fungi and lay a theoretical foundation for the ecological cultivation of G. elata.

17.
Front Microbiol ; 13: 1014970, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386721

RESUMO

As a fish unique to Yunnan Province in China, Sinocyclocheilus grahami hosts abundant potential probiotic resources in its intestinal tract. However, the genomic characteristics of the probiotic potential bacteria in its intestine and their effects on S. grahami have not yet been established. In this study, we investigated the functional genomics and host response of a strain, Lactobacillus salivarius S01, isolated from the intestine of S. grahami (bred in captivity). The results revealed that the total length of the genome was 1,737,623 bp (GC content, 33.09%), comprised of 1895 genes, including 22 rRNA operons and 78 transfer RNA genes. Three clusters of antibacterial substances related genes were identified using antiSMASH and BAGEL4 database predictions. In addition, manual examination confirmed the presence of functional genes related to stress resistance, adhesion, immunity, and other genes responsible for probiotic potential in the genome of L. salivarius S01. Subsequently, the probiotic effect of L. salivarius S01 was investigated in vivo by feeding S. grahami a diet with bacterial supplementation. The results showed that potential probiotic supplementation increased the activity of antioxidant enzymes (SOD, CAT, and POD) in the hepar and reduced oxidative damage (MDA). Furthermore, the gut microbial community and diversity of S. grahami from different treatment groups were compared using high-throughput sequencing. The diversity index of the gut microbial community in the group supplemented with potential probiotics was higher than that in the control group, indicating that supplementation with potential probiotics increased gut microbial diversity. At the phylum level, the abundance of Proteobacteria decreased with potential probiotic supplementation, while the abundance of Firmicutes, Actinobacteriota, and Bacteroidota increased. At the genus level, there was a decrease in the abundance of the pathogenic bacterium Aeromonas and an increase in the abundance of the potential probiotic bacterium Bifidobacterium. The results of this study suggest that L. salivarius S01 is a promising potential probiotic candidate that provides multiple benefits for the microbiome of S. grahami.

18.
Comput Intell Neurosci ; 2022: 6530884, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36199963

RESUMO

Objective: This investigation was to test the potential role of m6A-related long non-coding RNAs (lncRNAs) and immune infiltration as crucial factors in the diagnosis and treatment of uterine corpus endometrial cancer (UCEC). Method: The UCEC RNA-seq data were downloaded in the Cancer Genome Atlas (TCGA, https://portal.gdc.cancer.gov/). There were 587 samples totally, containing 543 UCEC cases and 35 healthy cases. The clinical information of UCEC cases included survival time, survival status, gender, age, stage, and TMN stage. Twenty-three m6A-related genes were found in published journals. The RNA-seq documents of UCEC were downloaded in the Cancer Genome Atlas (TCGA). The hub gene data of UCEC were downloaded from GEPIA2 database. The different packages of R language were applied to calculate and analyze in this research. Results: Among 587 cases in our study, we discovered 3039 lncRNAs in the TCGA-UCEC database. After the differential analysis, 23 m6A-associated genetics were screened and twenty-one m6A-associated differential genetics were found. In the end, we obtained 20 m6A-related lncRNAs. LNCTAM34A was considered as a predictive gene through univariate and multivariate Cox regression analysis. In addition to the above, patients with high LNCTAM34A expression had better outcomes than those with low LNCTAM34A expression. The high-risk cohort had greater scores of activated dendritic cells (aDCs), B cells, and T cell regulatory (Tregs) than low-risk cohort; in the meanwhile, high-risk cohort had lower scores of DCs and iDCs. Then, the high-risk cohort displayed greater scores in the immune functions of MHC class I, para-inflammation, and type I IFN response than those of low-risk cohort. Among 27 immune-inducible genes, the level of CD244, KIR3DLI, NRP1, PDCD1LG2, and TNFRSF8 was reduced in UCEC samples and the level of CD27, CD28, CD70, CD80, CD86, HAVCR2, ICOS, IDO1, LAIR1, PDCD1, TIGIT, TNFRSF18, -25, -9, -14, and VTCN1 was increased in UCEC samples. Conclusion: The key role of M6A-related lncRNAs in immune microenvironment in high-risk patients of UCEC. The patients with strong expression of LNCTAM34A have a good prognosis, and LNCTAM34A can be used as a prognostic gene for UCEC. m6A-related lncRNAs can be used as a potential treatment for UCEC. Our observations can be used as a hypothetical basis for future in vitro and animal experiments.


Assuntos
Neoplasias do Endométrio , RNA Longo não Codificante , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Antígenos CD28/genética , Antígenos CD28/metabolismo , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Genes Neoplásicos , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Microambiente Tumoral
19.
Toxics ; 10(9)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36136505

RESUMO

The safety of deep geological repositories is important in the disposal of high-level radioactive waste (HLW). In this study, advection−dispersion experiments were designed to build a transport model through a calibration/validation process, and the transport behavior of tritiated water (HTO) and various iodine species (iodide: I− and iodate: IO3−) was studied on a dynamic compacted granite column. Breakthrough curves (BTCs) were plotted under various flow rates (1−5 mL/min). BTCs showed that the non-sorption effect by anion exclusion was observed only in I− transport because the retardation factor (R) of I− was lower than that of HTO (R = 1). Moreover, equilibrium and nonequilibrium transport models were used and compared to identify the mobile/immobile zones in the compacted granite column. The anion exclusion effect was influenced by the immobile zones in the column. The non-sorption effect by anion exclusion (R < 1) was only observed for I− at 5.0 ± 0.2 mL/min flow rate, and a relatively higher Coulomb's repulsive force may be caused by the smaller hydration radius of I−(3.31 Å) than that of IO3−(3.74 Å).

20.
Ann Transl Med ; 10(14): 778, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35965818

RESUMO

Background: Chronic suppurative otitis media (CSOM) is a common otolaryngology disease, and cholesteatoma is the most aggressive type of CSOM. CSOM with and without cholesteatoma both result in a certain level of sensorineural damage, which can be categorized as air conduction (AC), bone conduction (BC), or air-bone gap (ABG), and AC, BC, and ABG are affected by many factors. Further analyses and comparisons of factors affecting sensorineural damage in CSOM with and without cholesteatoma were conducted in this study. Methods: A comparative study was conducted of 79 patients with CSOM (39 with cholesteatoma and 40 without cholesteatoma) whose diagnoses were mainly based on chronic middle ear infections and hearing loss (HL), typical computed tomography (CT) and surgical findings. Audiological evaluation included AC, BC and ABG, and sensorineural damage was defined as mixed and sensorineural HL (SNHL). Results: In relation to the types of HL, there were no significant differences between both groups. The CSOM with cholesteatoma group had significantly greater AC (P=0.000) and a significantly greater ABG (P>0.05) than the CSOM without cholesteatoma group, but BC did not differ significantly between both groups (P>0.05). The average AC-middle frequency (MF), AC-high frequency (HF), ABG-MF and ABG-HF of CSOM without cholesteatoma were smaller than these of CSOM with cholesteatoma (P<0.05). The degree of HL differed significantly between both groups (P=0.000). The CSOM with cholesteatoma group showed a higher level of HL than the CSOM without cholesteatoma group. The presence of cholesteatoma was presented a protective factor associated with sensorineural damage (P<0.05), while higher degrees of hearing and aging were risk factors (P<0.05), respectively. Conclusions: Our direct comparisons showed that HL progressed more rapidly in the CSOM with cholesteatoma group, which had higher frequencies in relation to AC, the ABG, and severity. However, in relation to BC, there were no significant differences between both groups, which was in line with the similar proportions of the types of HL in both groups. The logistic regression showed that the presence of cholesteatoma was a protective factor, and the degree of hearing and aging were risk factors associated with sensorineural damage.

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