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2.
Front Plant Sci ; 15: 1355832, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38721340

RESUMO

Lycium barbarum L., commonly known as wolfberry, is not only a traditional Chinese medicine but also a highly nutritious food. Its main nutrients include L. barbarum polysaccharide, flavonoid polyphenols, carotenoids, alkaloids, and other compounds, demonstrating its wide application value. This study investigated the effects of nitrogen application on the accumulation of the main nutrients and metabolites in wolfberry fruits under three different nitrogen application rates, namely, N1 (20% nitrogen (N) reduction, 540 kg·ha-2), N2 (medium N, 675 kg·ha-2), and N3 (20% nitrogen increase, 810 kg·ha-2,which is a local conventional nitrogen application amount.). Additionally, due to continuous branching, blossoming, and fruiting of wolfberry plants during the annual growth period, this research also explored the variation in nutritional composition among different harvesting batches. The contents of total sugar and polysaccharide in wolfberry fruit were determined by Fehling reagent method and phenol-sulfuric acid method, respectively;The content of betaine in fruit was determined by high-performance liquid chromatography,and the flavonoids and carotene in the wolfberry fruits were determined by spectrophotometry. Analysis of data over three consecutive years revealed that as nitrogen application increased, the total sugar content in wolfberry fruits initially decreased and then increased. The levels of L. barbarum polysaccharides, total flavonoids, and total carotenoids initially increased and then decreased, while the betaine content consistently increased. Different picking batches significantly impacted the nutrient content of wolfberry fruits. Generally, the first batch of summer wolfberry fruits had greater amounts of total sugar and flavonoids, whereas other nutrients peaked in the third batch. By employing a broadly targeted metabolomics approach, 926 different metabolites were identified. The top 20 differentially abundant metabolites were selected for heatmap generation, revealing that the contents of L-citrulline, 2-methylglutaric acid, and adipic acid increased proportionally to the nitrogen gradient. Conversely, the dibutyl phthalate and 2, 4-dihydroxyquinoline contents significantly decreased under high-nitrogen conditions. The remaining 15 differentially abundant metabolites, kaempferol-3-O-sophorosid-7-O-rhamnoside, trigonelline, and isorhamnosid-3-O-sophoroside, initially increased and then decreased with increasing nitrogen levels. Isofraxidin, a common differentially abundant metabolite across all treatments, is a coumarin that may serve as a potential biomarker for wolfberry fruit response to nitrogen. Differentially abundant metabolites were analyzed for GO pathway involvement, revealing significant enrichment in metabolic pathways and biosynthesis of secondary metabolites under different nitrogen treatments. In conclusion, a nitrogen application of 675 kg·ha-2, 20% less than the local farmers' actual application, was most beneficial for the quality of four-year-old Ningqi 7 wolfberry fruits. Consumers who purchase wolfberry-dried fruit for health benefits should not consider only the first batch of summer wolfberry fruits. These results offer a broader perspective for enhancing the quality and efficiency of the wolfberry industry.

3.
J Am Heart Assoc ; 13(9): e033474, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38700020

RESUMO

BACKGROUND: Copper exposure is reported to be associated with increased risk of stroke. However, the association of copper exposure with subclinical carotid atherosclerosis remains unclear. METHODS AND RESULTS: This observational study included consecutive participants from Xinqiao Hospital between May 2020 and August 2021. Blood metals were measured using inductively coupled plasma mass spectrometry and carotid atherosclerosis was assessed using ultrasound. Modified Poisson regression was performed to evaluate the associations of copper and other metals with subclinical carotid plaque presence. Blood metals were analyzed as categorical according to the quartiles. Multivariable models were adjusted for age, sex, body mass index, education, smoking, drinking, hypertension, diabetes, dyslipidemia, estimated glomerular filtration rate, and coronary artery disease history. Bayesian Kernel Machine Regression was conducted to evaluate the overall association of metal mixture with subclinical carotid plaque presence. One thousand five hundred eighty-five participants were finally enrolled in our study, and carotid plaque was found in 1091 subjects. After adjusting for potential confounders, metal-progressively-adjusted models showed that blood copper was positively associated with subclinical carotid plaque (relative risk according to comparing quartile 4 to quartile 1 was 1.124 [1.021-1.238], relative risk according to per interquartile increment was 1.039 [1.008-1.071]). Blood cadmium and lead were also significantly associated with subclinical carotid plaque. Bayesian Kernel Machine Regression analyses suggested a synergistic effect of copper-cadmium-lead mixture on subclinical carotid plaque presence. CONCLUSIONS: Our findings identify copper as a novel risk factor of subclinical carotid atherosclerosis and show the potential synergistic proatherogenic effect of copper, cadmium, and lead mixture.


Assuntos
Doenças das Artérias Carótidas , Cobre , Humanos , Feminino , Masculino , Doenças das Artérias Carótidas/sangue , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/epidemiologia , Cobre/sangue , Pessoa de Meia-Idade , Fatores de Risco , Idoso , Placa Aterosclerótica/sangue , Cádmio/sangue , Medição de Risco , China/epidemiologia , Biomarcadores/sangue , Doenças Assintomáticas , Chumbo/sangue
4.
Front Plant Sci ; 15: 1392175, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38736439

RESUMO

Wolfberry (Lycium, of the family Solanaceae) has special nutritional benefits due to its valuable metabolites. Here, 16 wolfberry-specific metabolites were identified by comparing the metabolome of wolfberry with those of six species, including maize, rice, wheat, soybean, tomato and grape. The copy numbers of the riboflavin and phenyllactate degradation genes riboflavin kinase (RFK) and phenyllactate UDP-glycosyltransferase (UGT1) were lower in wolfberry than in other species, while the copy number of the phenyllactate synthesis gene hydroxyphenyl-pyruvate reductase (HPPR) was higher in wolfberry, suggesting that the copy number variation of these genes among species may be the main reason for the specific accumulation of riboflavin and phenyllactate in wolfberry. Moreover, the metabolome-based neighbor-joining tree revealed distinct clustering of monocots and dicots, suggesting that metabolites could reflect the evolutionary relationship among those species. Taken together, we identified 16 specific metabolites in wolfberry and provided new insight into the accumulation mechanism of species-specific metabolites at the genomic level.

5.
BMC Psychiatry ; 24(1): 297, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641813

RESUMO

BACKGROUND: This study aimed to investigate the interplay between anxiety and depressive symptoms in Chinese college freshmen using the causal system perspective (CSP), which differs from the traditional common cause perspective (CCP) by providing an alternative explanation by attributing comorbidity to direct interactions among symptoms. METHODS: A convenience sample of 2,082 Chinese college freshmen (39.51% male, Mage = 18.61) from a normal university completed the Generalized Anxiety Disorder 7-Item Scale (GAD-7) and the Patient Health Questionnaire (PHQ-9). Network analysis was conducted and evaluated as to centrality, stability, node predictability, and bridging features. Moreover, the moderated network model (MNM) was utilized to detect the moderation effects of gender in the comorbidity network. RESULTS: The network of anxiety and depressive symptoms exhibited stability, characterized by the core symptoms of "restlessness", "lack of energy", and "excessive worry about control", as well as the bridging symptoms of "fearfulness", "sad mood", and "irritability". Notably, the nodes representing "uncontrollable worry" and "difficulty in relaxation" demonstrated the highest predictive power. Gender did not exert any moderating effects on the anxiety and depressive symptom network. CONCLUSION: These results reinforce that certain anxiety or depressive symptoms are more central than others, and thus play a more vital role in the comorbid network. These findings highlight underlying potential targeting symptoms to consider in future interventions.


Assuntos
Ansiedade , Depressão , Masculino , Humanos , Adolescente , Feminino , Depressão/diagnóstico , Depressão/epidemiologia , Universidades , Ansiedade/epidemiologia , Ansiedade/diagnóstico , Transtornos de Ansiedade/diagnóstico , Transtornos de Ansiedade/epidemiologia , Comorbidade
6.
Front Immunol ; 15: 1319698, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646543

RESUMO

This study explored the impacts of supplementation of different levels of coated methionine (Met) in a high-plant protein diet on growth, blood biochemistry, antioxidant capacity, digestive enzymes activity and expression of genes related to TOR signaling pathway in gibel carp (Carassius auratus gibeilo). A high-plant protein diet was formulated and used as a basal diet and supplemented with five different levels of coated Met at 0.15, 0.30, 0.45, 0.60 and 0.75%, corresponding to final analyzed Met levels of 0.34, 0.49, 0.64, 0.76, 0.92 and 1.06%. Three replicate groups of fish (initial mean weight, 11.37 ± 0.02 g) (20 fish per replicate) were fed the test diets over a 10-week feeding period. The results indicated that with the increase of coated Met level, the final weight, weight gain (WG) and specific growth rate initially boosted and then suppressed, peaking at 0.76% Met level (P< 0.05). Increasing dietary Met level led to significantly increased muscle crude protein content (P< 0.05) and reduced serum alanine aminotransferase activity (P< 0.05). Using appropriate dietary Met level led to reduced malondialdehyde concentration in hepatopancreas (P< 0.05), improved superoxide dismutase activity (P< 0.05), and enhanced intestinal amylase and protease activities (P< 0.05). The expression levels of genes associated with muscle protein synthesis such as insulin-like growth factor-1, protein kinase B, target of rapamycin and eukaryotic initiation factor 4E binding protein-1 mRNA were significantly regulated, peaking at Met level of 0.76% (P< 0.05). In conclusion, supplementing optimal level of coated Met improved on fish growth, antioxidant capacity, and the expression of TOR pathway related genes in muscle. The optimal dietary Met level was determined to be 0.71% of the diet based on quadratic regression analysis of WG.


Assuntos
Ração Animal , Antioxidantes , Suplementos Nutricionais , Metionina , Transdução de Sinais , Serina-Treonina Quinases TOR , Animais , Metionina/administração & dosagem , Serina-Treonina Quinases TOR/metabolismo , Antioxidantes/metabolismo , Ração Animal/análise , Carpa Dourada/crescimento & desenvolvimento , Carpa Dourada/genética , Carpa Dourada/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos
7.
Phytomedicine ; 129: 155612, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38669968

RESUMO

BACKGROUND: Colorectal cancer (CRC) continues to be a major global health challenge, ranking as a top cause of cancer-related mortality. Alarmingly, the five-year survival rate for CRC patients hovers around a mere 10-30 %. The disruption of fibroblast growth factor receptor (FGFRs) signaling pathways is significantly implicated in the onset and advancement of CRC, presenting a promising target for therapeutic intervention in CRC management. Further investigation is essential to comprehensively elucidate FGFR1's function in CRC and to create potent therapies that specifically target FGFR1. PURPOSE: This study aims to demonstrate the oncogenic role of FGFR1 in colorectal cancer and to explore the potential of ß,ß-dimethylacrylalkannin (ß,ß-DMAA) as a therapeutic option to inhibit FGFR1. METHODS: In this research, we employed a comprehensive suite of techniques including tissue array, kinase profiling, computational docking, knockdown assay to predict and explore the inhibitor of FGFR1. Furthermore, we utilized kinase assay, pull-down, cell proliferation tests, and Patient derived xenograft (PDX) mouse models to further investigate a novel FGFR1 inhibitor and its impact on the growth of CRC. RESULTS: In our research, we discovered that FGFR1 protein is markedly upregulated in colorectal cancer tissues, suggesting a significant role in regulating cellular proliferation, particularly in patients with colorectal cancer. Furthermore, we conducted a computational docking, kinase profiling analysis, simulation and identified that ß,ß-DMAA could directly bind with FGFR1 within ATP binding pocket domain. Cell-based assays confirmed that ß,ß-DMAA effectively inhibited the proliferation of colon cancer cells and also triggered cell cycle arrest, apoptosis, and altered FGFR1-mediated signaling pathways. Moreover, ß,ß-DMAA effectively attenuated the development of PDX tumors in mice that were FGFR1-positive, with no notable toxicity observed. In summary, our study highlights the pivotal role of FGFR1 in colorectal cancer, suggesting that inhibiting FGFR1 activity could be a promising strategy for therapeutic intervention. We present strong evidence that targeting FGFR1 with ß,ß-DMAA is a viable approach for the management of colorectal cancer. Given its low toxicity and high efficacy, ß,ß-DMAA, as an FGFR1 inhibitor, warrants further investigation in clinical settings for the treatment of FGFR1-positive tumors.

8.
aBIOTECH ; 5(1): 17-28, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38576436

RESUMO

Small RNA (sRNA)-mediated RNA silencing (also known as RNA interference, or RNAi) is a conserved mechanism in eukaryotes that includes RNA degradation, DNA methylation, heterochromatin formation and protein translation repression. In plants, sRNAs can move either cell-to-cell or systemically, thereby acting as mobile silencing signals to trigger noncell autonomous silencing. However, whether and what proteins are also involved in noncell autonomous silencing have not been elucidated. In this study, we utilized a previously reported inducible RNAi plant, PDSi, which can induce systemic silencing of the endogenous PDS gene, and we demonstrated that DCL3 is involved in systemic PDS silencing through its RNA binding activity. We confirmed that the C-terminus of DCL3, including the predicted RNA-binding domain, is capable of binding short RNAs. Mutations affecting RNA binding, but not processing activity, reduced systemic PDS silencing, indicating that DCL3 binding to RNAs is required for the induction of systemic silencing. Cucumber mosaic virus infection assays showed that the RNA-binding activity of DCL3 is required for antiviral RNAi in systemically noninoculated leaves. Our findings demonstrate that DCL3 acts as a signaling agent involved in noncell autonomous silencing and an antiviral effect in addition to its previously known function in the generation of 24-nucleotide sRNAs. Supplementary Information: The online version contains supplementary material available at 10.1007/s42994-023-00124-6.

9.
J Agric Food Chem ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557018

RESUMO

In this study, in silico analysis and peptidomics were performed to examine the generation mechanism of the umami taste of fermented broad bean paste (FBBP). Based on the information from peptidomics, a total of 470 free peptides were identified from FBBP, most of which were increased after fermentation. Additionally, the increase of the content of umami peptides, organic acids, and amino acids during fermentation contributed to the perception of umami taste in FBBP. Molecule docking results inferred that these umami molecules were easy to connect with Ser, Glu, His, and Gln in the T1R3 subunit through hydrogen bonds and electrostatic interaction force. The binding sites His145, Gln389, and Glu301 particularly contributed to the formation of the ligand-receptor complexes. The aromatic interaction, hydrogen bond, hydrophilicity, and solvent-accessible surface (SAS) played key roles in the receptor-peptide interaction. Sensory evaluation and electronic tongue results showed that EDEDE, DLSESV, SNGDDE, DETL, CDLSD, and TDEE screened from FBBP had umami characteristics and umami-enhancing effects (umami threshold values ranging from 0.131 to 0.394 mmol/L). This work provides new insight into the rapid and efficient screening of novel umami peptides and a deeper understanding of the taste mechanisms of umami molecules from FBBP.

10.
aBIOTECH ; 5(1): 114, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38576432

RESUMO

[This corrects the article DOI: 10.1007/s42994-023-00124-6.].

11.
Food Chem ; 450: 139297, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38631199

RESUMO

This study aimed to investigate the antioxidative and cytoprotective activity of antioxidant peptides from fermented broad bean paste (FBBP) and explore their potential molecular mechanisms using a combined in silico and in vitro approach. Seven novel antioxidant peptides (VSRRFIYYL, SPAIPLP, PVPPPGG, KKDGYWWAKFK, LAWY, LGFMQF, and LPGCP) identified by integrated approaches of peptidomics and in silico bioinformatic analysis were synthesized, exhibiting strong antioxidant potential against in vitro radicals. Molecular docking results suggested that these peptides could form stable hydrogen bonds and solvent-accessible surface with key amino acid residues of Keap1, thus potentially regulating the Keap1-Nrf2 pathway by occupying the Nrf2-binding site on Keap1. Additionally, they exhibited strong cellular antioxidant activity and could protect HepG2 cells from AAPH-induced oxidative injury by reducing reactive oxygen species and MDA accumulation. This study firstly unraveled the molecular mechanisms of antioxidant peptides from FBBP, and provided a new theoretical basis for the high-value utilization of FBBP.

12.
ACS Appl Mater Interfaces ; 16(13): 17041-17050, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38517684

RESUMO

The ultrafast manipulation of spin in ferromagnet-semiconductor (FM/SC) heterojunctions is a key issue for advancing spintronics, where magnetic damping and interfacial spin transport often define device efficiency. Leveraging selective optical excitation in semiconductors offers a unique approach to spin manipulation in FM/SC heterojunctions. Herein, we investigated the magnetic dynamics of a Co2FeAl/n-GaAs heterojunction using the time-resolved magneto-optical Kerr technique and observed the considerably enhanced magnetic damping of Co2FeAl when GaAs is photoexcited near its band edge. This enhancement is attributed to an enhanced spin-pumping effect facilitated by spin-dependent carrier tunneling and capture within the Co2FeAl layer. Moreover, circularly polarized light excites spin-polarized band-edge photocarriers, further impacting the magnetic damping of Co2FeAl through an additional optical spin-transfer torque on the magnetic moment of Co2FeAl. Our results provide a valuable reference for manipulating spin-pumping and interfacial spin transport in FM/SC heterojunctions, showcasing the advantage of optical control of semiconductor photocarriers for the ultrafast manipulation of magnetic dynamics and interfacial spin transfer.

13.
Int J Mol Med ; 53(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38426556

RESUMO

Following the publication of the above article, an interested reader drew to the authors' attention that, in Fig. 6 on p. 2898, the 'SAH' and 'SAH+NC' data panels contained an apparently overlapping section of data, such that these data appeared to have been derived from the same original source, even though they were intended to show the results from differently performed experiments. The authors have examined their original data, and realize that the 'SAH+NC' data panel had inadvertently been selected incorrectly for this figure. In addition, in response to a further query from the reader, the authors wished to point out that the standard deviations in their study were statistically analysed using GraphPad Prism software version 5.0a. The revised version of Fig. 6, now showing the correct data for the 'SAH+NC' experiment, is shown on the next page. The authors can confirm that the errors associated with this figure did not have any significant impact on either the results or the conclusions reported in this study, and all the authors agree with the publication of this Corrigendum. The authors are grateful to the Editor of International Journal of Molecular Medicine for allowing them the opportunity to publish this Corrigendum; furthermore, they apologize to the readership of the Journal for any inconvenience caused. [International Journal of Molecular Medicine 42: 2891­2902, 2018; DOI: 10.3892/ijmm.2018.3858].

14.
Front Plant Sci ; 15: 1310346, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38444537

RESUMO

Wolfberry, also known as goji berry or Lycium barbarum, is a highly valued fruit with significant health benefits and nutritional value. For more efficient and comprehensive usage of published L. barbarum genomic data, we established the Wolfberry database. The utility of the Wolfberry Genome Database (WGDB) is highlighted through the Genome browser, which enables the user to explore the L. barbarum genome, browse specific chromosomes, and access gene sequences. Gene annotation features provide comprehensive information about gene functions, locations, expression profiles, pathway involvement, protein domains, and regulatory transcription factors. The transcriptome feature allows the user to explore gene expression patterns using transcripts per kilobase million (TPM) and fragments per kilobase per million mapped reads (FPKM) metrics. The Metabolism pathway page provides insights into metabolic pathways and the involvement of the selected genes. In addition to the database content, we also introduce six analysis tools developed for the WGDB. These tools offer functionalities for gene function prediction, nucleotide and amino acid BLAST analysis, protein domain analysis, GO annotation, and gene expression pattern analysis. The WGDB is freely accessible at https://cosbi7.ee.ncku.edu.tw/Wolfberry/. Overall, WGDB serves as a valuable resource for researchers interested in the genomics and transcriptomics of L. barbarum. Its user-friendly web interface and comprehensive data facilitate the exploration of gene functions, regulatory mechanisms, and metabolic pathways, ultimately contributing to a deeper understanding of wolfberry and its potential applications in agronomy and nutrition.

15.
New Phytol ; 242(2): 558-575, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38396374

RESUMO

Black wolfberry (Lycium ruthenicum Murr.) contains various bioactive metabolites represented by flavonoids, which are quite different among production regions. However, the underlying regulation mechanism of flavonoid biosynthesis governing the bioactivity of black wolfberry remains unclear. Presently, we compared the bioactivity of black wolfberry from five production regions. Multi-omics were performed to construct the regulation network associated with the fruit bioactivity. The detailed regulation mechanisms were identified using genetic and molecular methods. Typically, Qinghai (QH) fruit exhibited higher antioxidant and anti-inflammatory activities. The higher medicinal activity of QH fruit was closely associated with the accumulation of eight flavonoids, especially Kaempferol-3-O-rutinoside (K3R) and Quercetin-3-O-rutinoside (rutin). Flavonoid biosynthesis was found to be more active in QH fruit, and the upregulation of LrFLS, LrCHS, LrF3H and LrCYP75B1 caused the accumulation of K3R and rutin, leading to high medicinal bioactivities of black wolfberry. Importantly, transcription factor LrMYB94 was found to regulate LrFLS, LrCHS and LrF3H, while LrWRKY32 directly triggered LrCYP75B1 expression. Moreover, LrMYB94 interacted with LrWRKY32 to promote LrWRKY32-regulated LrCYP75B1 expression and rutin synthesis in black wolfberry. Transgenic black wolfberry overexpressing LrMYB94/LrWRKY32 contained higher levels of K3R and rutin, and exhibited high medicinal bioactivities. Importantly, the LrMYB94/LrWRKY32-regulated flavonoid biosynthesis was light-responsive, showing the importance of light intensity for the medicinal quality of black wolfberry. Overall, our results elucidated the regulation mechanisms of K3R and rutin synthesis, providing the basis for the genetic breeding of high-quality black wolfberry.


Assuntos
Lycium , Lycium/genética , Melhoramento Vegetal , Flavonoides , Antioxidantes , Rutina , Frutas/genética
16.
Microb Ecol ; 87(1): 43, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363394

RESUMO

Biological soil crusts (biocrusts) are considered "desert ecosystem engineers" because they play a vital role in the restoration and stability maintenance of deserts, including those cold sandy land ecosystems at high latitudes, which are especially understudied. Microorganisms participate in the formation and succession of biocrusts, contributing to soil properties' improvement and the stability of soil aggregates, and thus vegetation development. Accordingly, understanding the composition and successional characteristics of microorganisms is a prerequisite for analyzing the ecological functions of biocrusts and related applications. Here, the Hulun Buir Sandy Land region in northeastern China-lying at the highest latitude of any sandy land in the country-was selected for study. Through a field investigation and next-generation sequencing (Illumina MiSeq PE300 Platform), our goal was to assess the shifts in diversity and community composition of soil bacteria and fungi across different stages during the succession of biocrusts in this region, and to uncover the main factors involved in shaping their soil microbial community. The results revealed that the nutrient enrichment capacity of biocrusts for available nitrogen, total nitrogen, total phosphorus, total content of water-soluble salt, available potassium, soil organic matter, and available phosphorus was progressively enhanced by the succession of cyanobacterial crusts to lichen crusts and then to moss crusts. In tandem, soil bacterial diversity increased as biocrust succession proceeded but fungal diversity decreased. A total of 32 bacterial phyla and 11 fungal phyla were identified, these also known to occur in other desert ecosystems. Among those taxa, the relative abundance of Proteobacteria and Cyanobacteria significantly increased and decreased, respectively, along the cyanobacterial crust-lichen-moss crust successional gradient. However, for Actinobacteria, Chloroflexi, and Acidobacteria their changed relative abundance was significantly hump-shaped, increasing in the shift from cyanobacterial crust to lichen crust, and then decreasing as lichen crust shifted to moss crust. In this process, the improved soil properties effectively enhanced soil bacterial and fungal community composition. Altogether, these findings broaden our understanding about how soil microbial properties can change during the succession of biocrusts in high-latitude, cold sandy land ecosystems.


Assuntos
Cianobactérias , Líquens , Microbiota , Ecossistema , Solo , Areia , Microbiologia do Solo , Nitrogênio , Fósforo , China
17.
Heliyon ; 10(4): e26035, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38370181

RESUMO

Lead-based reactor is a new type of reactor using liquid lead or lead-bismuth alloy as a coolant. As the core working element of the main pump, the impeller is subjected to a huge load when conveying heavy metal liquids and is highly susceptible to damage. In this study, we used ANSYS and FLUENT software to investigate the stress, deformation, and creep deformation of the nuclear main pump impeller under a liquid lead-bismuth environment by the fluid-solid coupling method. The maximum equivalent force of the impeller was located at the junction of the blade and hub, which was prone to fatigue damage under the action of alternating load. The stress, deformation, and creep characteristics of the impeller blade were observed to generally increase with rotational speed. Particularly, the junction of the blade root and hub exhibited high susceptibility to stress concentration and fatigue damage. At a flow rate of 0.64 m/s and a speed of 690 r/min, the maximum equivalent force was 16.7 MPa, which was lower than the yield strength of 316L stainless steel. Additionally, the maximum deformation was less than 0.63 mm. Over a five-year period, the creep of the impeller ranged from a minimum of 0.228% to a maximum of 0.447%, indicating that the impeller can reliably operate in a liquid lead-bismuth environment for at least five years.

18.
J Glob Antimicrob Resist ; 36: 319-325, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38266958

RESUMO

OBJECTIVES: This study reports the whole-genome sequences of two strains of extended-spectrum beta-lactamase (ESBL)-producing and multidrug-resistant (MDR) K. pneumoniae ST268 and explores their acquired antibiotic resistance genes (ARGs) and the mobile genetic elements (MGEs). METHODS: Two strains of K. pneumoniae ST268 were isolated from different samples of one patient. Assessment of antimicrobial susceptibility was performed, and then whole-genome sequencing was conducted. Acquired ARGs, insertion sequences, and transposons harboured by the two strains of K. pneumoniae ST268 were identified, and then the genetic contexts associated with the ARGs were analysed systematically. RESULTS: Two strains of K. pneumoniae ST268 were found to carry the 118.6-kb hybrid IncFIIK:IncQ1:repBR1701 plasmid. All the acquired ARGs carried by the IncF plasmid were found to be situated on the 25.3-kb MDR region bracketed by ISKpn19 and IS26, which was widely present in the plasmids in 14 STs of strains in K. pneumoniae but also in IncF plasmids from Shigella flexneri and Klebsiella quasipneumoniae. Notably, the IncF plasmids harbouring the 25.3-kb MDR region were geographically distributed mainly in China, and the pKP161637-1/pKP160802-1 in our study was the first report on the IncF plasmid carrying the 25.3-kb MDR region bracketed in K. pneumoniae ST268. CONCLUSIONS: Two strains of ESBL-producing K. pneumoniae ST268 with a MDR IncF plasmid were identified in a hospital in China. The ARGs were identified on the 25.3-kb MDR region, bracketed by ISKpn19 and IS26, of the IncF plasmids, which were present not only in the K. pneumoniae but also in the S. flexneri and K. quasipneumoniae.


Assuntos
Infecções por Klebsiella , Klebsiella pneumoniae , Humanos , Klebsiella pneumoniae/genética , Escherichia coli/genética , beta-Lactamases/genética , Antibacterianos/farmacologia , Genômica
19.
Plant Biotechnol J ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38194521

RESUMO

Wolfberry is a plant with medicinal and food values. However, its bioactive ingredients and the corresponding genetic bases have not been determined. Here, we de novo generated a chromosome-level genome assembly for wolfberry, yielding a genome sequence of ~1.77 Gb with contig N50 of 50.55 Mb and 39 224 predicted gene models. A variation map, using 307 re-sequenced accessions, was called based on this genome assembly. Furthermore, the fruit metabolome of these accessions was profiled using 563 annotated metabolites, which separated Lycium barbarum L. and non-L. barbarum L. The flavonoids, coumarins, alkaloids and nicotinic acid contents were higher in the former than in the latter. A metabolite-based genome-wide association study mapped 156 164 significant single nucleotide polymorphisms corresponding to 340 metabolites. This included 19 219 unique lead single nucleotide polymorphisms in 1517 significant association loci, of which three metabolites, flavonoids, betaine and spermidine, were highlighted. Two candidate genes, LbUGT (evm.TU.chr07.2692) and LbCHS (evm.TU.chr07.2738), with non-synonymous mutations, were associated with the flavonoids content. LbCHS is a structural gene that interacts with a nearby MYB transcription factor (evm.TU.chr07.2726) both in L. barbarum and L. ruthenicum. Thus, these three genes might be involved in the biosynthesis/metabolism of flavonoids. LbSSADH (evm.TU.chr09.627) was identified as possibly participating in betaine biosynthesis/metabolism. Four lycibarbarspermidines (E-G and O) were identified, and only the lycibarbarspermidines O content was higher in L. barbarum varieties than in non-L. barbarum varieties. The evm.TU.chr07.2680 gene associated with lycibarbarspermidines O was annotated as an acetyl-CoA-benzylalcohol acetyltransferase, suggesting that it is a candidate gene for spermidine biosynthesis. These results provide novel insights into the specific metabolite profile of non-L. barbarum L. and the genetic bases of flavonoids, betaine and spermidine biosynthesis/metabolism.

20.
Biomed Opt Express ; 15(1): 131-141, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38223172

RESUMO

A coherent anti-Stokes Raman scattering (CARS)-based multimodality microscopy system was developed using a single Ti:sapphire femtosecond laser source for biological imaging. It provides three complementary and co-registered imaging modalities: CARS, MPM (multiphoton microscopy), and RCM (reflectance confocal microscopy). The imaging speed is about 1 frame-per-second (fps) with a digital resolution of 1024 × 1024 pixels. This microscopy system can provide clear 2-dimensional and 3-dimensional images of ex-vivo biological tissue samples. Its spectral selection initiates vibrational excitation in lipid cells (approximately 2850 cm-1) using two filters on the pump and Stokes beam paths. The excitation can be tuned over a wide spectral range with adjustable spectral filters. The imaging capability of this CARS-based multimodal microscopy system was demonstrated using porcine fat, murine skin, and murine liver tissue samples.

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