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1.
Mol Plant Pathol ; 25(4): e13452, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619823

RESUMO

Phytophthora root and stem rot of soybean (Glycine max), caused by the oomycete Phytophthora sojae, is an extremely destructive disease worldwide. In this study, we identified GmEIL1, which encodes an ethylene-insensitive3 (EIN3) transcription factor. GmEIL1 was significantly induced following P. sojae infection of soybean plants. Compared to wild-type soybean plants, transgenic soybean plants overexpressing GmEIL1 showed enhanced resistance to P. sojae and GmEIL1-silenced RNA-interference lines showed more severe symptoms when infected with P. sojae. We screened for target genes of GmEIL1 and confirmed that GmEIL1 bound directly to the GmERF113 promoter and regulated GmERF113 expression. Moreover, GmEIL1 positively regulated the expression of the pathogenesis-related gene GmPR1. The GmEIL1-regulated defence response to P. sojae involved both ethylene biosynthesis and the ethylene signalling pathway. These findings suggest that the GmEIL1-GmERF113 module plays an important role in P. sojae resistance via the ethylene signalling pathway.


Assuntos
Fabaceae , Phytophthora , Fatores de Transcrição/genética , Soja/genética , Etilenos , Plantas Geneticamente Modificadas
2.
World J Gastrointest Oncol ; 16(4): 1465-1478, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38660658

RESUMO

BACKGROUND: Colorectal cancer has a low 5-year survival rate and high mortality. Human ß-defensin-1 (hBD-1) may play an integral function in the innate immune system, contributing to the recognition and destruction of cancer cells. Long non-coding RNAs (lncRNAs) are involved in the process of cell differentiation and growth. AIM: To investigate the effect of hBD-1 on the mammalian target of rapamycin (mTOR) pathway and autophagy in human colon cancer SW620 cells. METHODS: CCK8 assay was utilized for the detection of cell proliferation and determination of the optimal drug concentration. Colony formation assay was employed to assess the effect of hBD-1 on SW620 cell proliferation. Bioinformatics was used to screen potentially biologically significant lncRNAs related to the mTOR pathway. Additionally, p-mTOR (Ser2448), Beclin1, and LC3II/I expression levels in SW620 cells were assessed through Western blot analysis. RESULTS: hBD-1 inhibited the proliferative ability of SW620 cells, as evidenced by the reduction in the colony formation capacity of SW620 cells upon exposure to hBD-1. hBD-1 decreased the expression of p-mTOR (Ser2448) protein and increased the expression of Beclin1 and LC3II/I protein. Furthermore, bioinformatics analysis identified seven lncRNAs (2 upregulated and 5 downregulated) related to the mTOR pathway. The lncRNA TCONS_00014506 was ultimately selected. Following the inhibition of the lncRNA TCONS_00014506, exposure to hBD-1 inhibited p-mTOR (Ser2448) and promoted Beclin1 and LC3II/I protein expression. CONCLUSION: hBD-1 inhibits the mTOR pathway and promotes autophagy by upregulating the expression of the lncRNA TCONS_00014506 in SW620 cells.

3.
Electrophoresis ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38533931

RESUMO

Multiplex PCR is a critical step when preparing amplicon library for next-generation sequencing. However, there are several challenges related to multiplex PCR including poor uniformity, nonspecific amplification, and primer-dimers. To address these issues, we propose a novel solution strategy that involves using a low cycle number (<10 cycles) in multiplex PCR and then employing carrier DNAs and magnetic beads for the selection of targeted products. This technique improves the amplicon uniformity while also reducing primer-dimers and PCR artifacts. To evaluate our technique, we initially utilized 120 DNA fragments from mouse genome containing single nucleotide polymorphism (SNP) sites. Sequencing results demonstrated that with only 7 cycles of multiplex PCR, 95.8% of the targeted SNP sites were mapped, with a coverage of at least 1×. The average sequencing depth of all amplicons was 1705.79 ± 1205.30×; 87% of them reached a coverage depth that exceeded 0.2-fold of the average sequencing depth. Our method had a greater uniformity (87%) when compared to Hi-Plex PCR (53.3%). Furthermore, we validated our strategy by randomly selecting 90 primer pairs twice from the initial set of 120 primer-pairs. Next, we used the same protocol to prepare amplicon libraries. The two groups had an average sequencing depth of 1013.30 ± 585.57× and 219.10 ± 158.27×, respectively; over 84% of the amplicons had a sequencing depth that exceeded 0.2-fold of average depth. These results suggest that the use of a low cycle number in multiplex PCR is a cost-effective and efficient approach for the preparation of amplicon libraries.

4.
Front Microbiol ; 15: 1353849, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38550871

RESUMO

Introduction: Carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-HvKP) strains combining virulence and multidrug resistance (MDR) features pose a great public health concern. The aim of this study is to explore the evolutionary characteristics of virulence in CR-HvKP by investigating the genetic features of resistance and virulence hybrid plasmids. Methods: The resistance and virulence phenotypes were determined by using antimicrobial susceptibility testing and the mouse bacteremia infection model, respectively. Plasmid profiles were investigated by S1 nuclease pulsed-field gel electrophoresis (S1-PFGE) and Southern blotting, conjugation assay, and whole genome sequencing (WGS). Bioinformatics tools were used to uncover the genetic features of the resistance and virulence hybrid plasmids. Results: Two ST11-KL64 CRKP clinical isolates (KP18-3-8 and KP18-2079), which exhibited enhanced virulence compared with the classic CRKP, were detected positive for blaKPC-2 and rmpA2. The virulence level of the hypermucoviscous strain KP18-3-8 was higher than that of KP18-2079. S1-PFGE, Southern hybridization and WGS analysis identified two novel hybrid virulence plasmids in KP18-3-8 (pKP1838-KPC-vir, 228,158 bp) and KP18-2079 (pKP1838-KPC-vir, 182,326 bp), respectively. The IncHI1B/repB-type plasmid pKP1838-KPC-vir co-harboring blaKPC-2 and virulence genes (rmpA2, iucABCD and iutA) but lacking type IV secretion system could transfer into non-hypervirulent ST11 K. pneumoniae with the assistance of a helper plasmid in conjugation. The IncFII/IncR-type virulence plasmid pKP18-2079-vir may have been generated as a result of recombination between a typical pLVPK-like virulence plasmid and an MDR plasmid. Conclusion: Our studies further highlight co-evolution of the virulence and resistance plasmids in ST11-CRKP isolates. Close surveillance of such hybrid virulence plasmids in clinical K. pneumoniae should be performed.

5.
Lupus ; 33(5): 470-480, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38442229

RESUMO

OBJECTIVE: This study aimed to investigate the correlation between positive psychological capital, post-traumatic growth, social support, and quality of life (QOL) in patients with systemic lupus erythematosus (SLE). METHODS: A cross-sectional study was conducted at the First Affiliated Hospital of Xinjiang Medical University from October 2022 to May 2023. A sample of 330 hospitalized SLE patients was selected for this study. The collected data included demographic information, the SLE disease activity index, the Positive Mental Capital Questionnaire, the Chinese version of the Post-Traumatic Growth Scale, the Social Support Rating Scale, and the Chinese version of the Lupus Quality of Life Scale. RESULTS: The QOL score among the 330 SLE patients was measured as M(P25, P75) of 105 (83.00,124.00). Positive psychological capital, post-traumatic growth, and social support demonstrated significant positive correlations with the QOL in SLE patients (p < 0.05). Multiple linear regression analysis revealed that literacy, disease level, disease duration, occupation, marital status, psychological capital, social support, and post-traumatic growth were influential factors associated with the QOL in SLE patients. CONCLUSION: Medical professionals should be attentive to the psychological well-being of SLE patients and should consider implementing early psychological interventions. These interventions are crucial for enhancing the QOL for individuals diagnosed with SLE.


Assuntos
Lúpus Eritematoso Sistêmico , Crescimento Psicológico Pós-Traumático , Humanos , Qualidade de Vida/psicologia , Estudos Transversais , Lúpus Eritematoso Sistêmico/complicações , Apoio Social , Inquéritos e Questionários
6.
Front Cardiovasc Med ; 11: 1302109, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38450369

RESUMO

Background: Exercise training is commonly employed as a efficacious supplementary treatment for individuals suffering from heart failure, but the optimal exercise regimen is still controversial. The objective of the review was to compare the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on the exercise capacity, cardiac function, quality of life (QoL) and heart rate among patients with heart failure with reduced ejection fraction. Methods: A systematic search was performed using the following eight databases from their inception to July 5, 2023: PubMed, Web of Science, Embase, Cochrane Library, Clinical Trials, China Knowledge Network, Wan fang Data, and the China Biology Medicine databases. The meta-analysis results were presented as mean difference (MD) and 95% confidence interval (CI). The Cochrane Risk of Bias tool was used for the included studies. The Grading of Recommendations Assessment, Development, and Evaluations was used to assess the certainty of evidence. Results: Thirteen randomized controlled trials were included in the study. The results showed that HIIT had a significant positive effect on peak oxygen uptake (MD = 1.78, 95% CI for 0.80-2.76), left ventricular ejection fraction (MD = 3.13, 95% CI for 1.25-5.02), six-minute walk test (MD = 28.13, 95% CI for 14.56-41.70), and Minnesota Living with Heart Failure Questionnaire (MD = -4.45, 95% CI for -6.25 to -2.64) compared to MICT. However, there were no statistically significant differences observed in resting heart rate and peak heart rate. Conclusions: HIIT significantly improves peak oxygen uptake, left ventricular ejection fraction, six-minute walk test, and Minnesota Living with Heart Failure Questionnaire in patients with heart failure with reduced ejection fraction. Additionally, HIIT exhibits greater effectiveness in improving peak oxygen uptake among patients with lower body mass index. Systematic Review Registration: https://www.doi.org/10.37766/inplasy2023.7.0100, identifier (INPLASY2023.7.0100).

7.
Proc Biol Sci ; 291(2018): 20232937, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38471545

RESUMO

Collembola is a highly diverse and abundant group of soil arthropods with chromosome numbers ranging from 5 to 11. Previous karyotype studies indicated that the Tomoceridae family possesses an exceptionally long chromosome. To better understand chromosome size evolution in Collembola, we obtained a chromosome-level genome of Yoshiicerus persimilis with a size of 334.44 Mb and BUSCO completeness of 97.0% (n = 1013). Both genomes of Y. persimilis and Tomocerus qinae (recently published) have an exceptionally large chromosome (ElChr greater than 100 Mb), accounting for nearly one-third of the genome. Comparative genomic analyses suggest that chromosomal elongation occurred independently in the two species approximately 10 million years ago, rather than in the ancestor of the Tomoceridae family. The ElChr elongation was caused by large tandem and segmental duplications, as well as transposon proliferation, with genes in these regions experiencing weaker purifying selection (higher dN/dS) than conserved regions. Moreover, inter-genomic synteny analyses indicated that chromosomal fission/fusion events played a crucial role in the evolution of chromosome numbers (ranging from 5 to 7) within Entomobryomorpha. This study provides a valuable resource for investigating the chromosome evolution of Collembola.


Assuntos
Artrópodes , Genoma , Animais , Artrópodes/genética , Genômica , Sintenia , Cariótipo , Evolução Molecular
8.
Artigo em Inglês | MEDLINE | ID: mdl-38366692

RESUMO

AIMS: To investigate the clinical and radiographic outcomes of a chemically modified sandblasted large-grit acid-etched implant (hydrophilic) in lateral sinus floor elevation (LSFE), compared with a conventional one (hydrophobic). MATERIALS AND METHODS: A retrospective study design was adopted. Patients who received LSFE with simultaneous implant placement were recruited. According to different types of implant surfaces, patients were divided into two groups (the hydrophilic group and the hydrophobic group). Implant survival rate (SR), endo-sinus bone stability on the radiographs, mean probing depths, percentage of bleeding on probing, marginal bone loss, and patient satisfaction were evaluated. RESULTS: A total of 106 patients with 180 implants (hydrophilic:101, hydrophobic:79) in 119 maxillary sinuses were included. The follow-up period ranged from 2 to 5 years. Three hydrophobic implants and one hydrophilic implant in four different patients failed. The SR of the hydrophilic group was higher than that of the hydrophobic group but without a significant difference (p > .05). The change and change rate of endo-sinus bone height (ΔESBH and RΔESBH ) and bone volume (ΔESBV and RΔESBV ) in the hydrophilic group were less than those in the hydrophobic group, with a significant difference at 6 months after implantation. No other significant difference was found between the two groups. CONCLUSION: Within the limitations of this study, both hydrophilic and hydrophobic implants were suitable for LSFE with predictable clinical outcomes. Meanwhile, hydrophilic implants could contribute to the grafted endo-sinus bone stability during healing time.

9.
BMC Immunol ; 25(1): 4, 2024 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-38195424

RESUMO

Immune cells, such as macrophages, B cells, neutrophils and T cell subsets, have been implicated in the context of obesity. However, the specific role of Th2 cells in adipose tissue function has remained elusive. Eight-week-old male CD3ε─/─ mice were randomly divided into two groups (≥ 5 mice per group): one received intravenous injection of Th2 cells isolated from LATY136F mice, while the other receiving PBS as a control. Both of groups were subjected to a high-fat diet (HFD). The adoptive transfer of polarized Th2 cells led to a significant reduction in obesity following a HFD. This reduction was accompanied by improvements in hepatic steatosis, glucose intolerance, and insulin resistance. Mechanistically, Th2 cell treatment promoted oxidative phosphorylation of adipocytes, thereby contributing to a reduction of lipid droplet accumulation. These findings suggest that Th2 cell therapy represents a novel approach for treating diet-induced obesity and other diseases involving lipid droplet accumulation disorders.


Assuntos
Dieta Hiperlipídica , Lipogênese , Masculino , Animais , Camundongos , Dieta Hiperlipídica/efeitos adversos , Células Th2 , Obesidade/terapia , Transferência Adotiva
10.
Comput Struct Biotechnol J ; 23: 537-548, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38235361

RESUMO

CRISPR-Cas9 systems constitute bacterial adaptive immune systems that protect against phage infections. Bacteriophages encode anti-CRISPR proteins (Acrs) that mitigate the bacterial immune response. However, the structural basis for their inhibitory actions from a molecular perspective remains elusive. In this study, through microsecond atomistic molecular dynamics simulations, we demonstrated the remarkable flexibility of Streptococcus pyogenes Cas9 (SpyCas9) and its conformational adaptability during interactions with AcrIIA4 and AcrIIA2. Specifically, we demonstrated that the binding of AcrIIA4 and AcrIIA2 to SpyCas9 induces a conformational rearrangement that causes spatial separation between the nuclease and cleavage sites, thus making the endonuclease inactive. This separation disrupts the transmission of signals between the protospacer adjacent motif recognition and nuclease domains, thereby impeding the efficient processing of double-stranded DNA. The simulation also reveals that AcrIIA4 and AcrIIA2 cause different structural variations of SpyCas9. Our research illuminates the precise mechanisms underlying the suppression of SpyCas9 by AcrIIA4 and AcrIIA2, thus presenting new possibilities for controlling genome editing with higher accuracy.

11.
Ecotoxicol Environ Saf ; 270: 115946, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38194808

RESUMO

With a growing number of research reports on microplastics (MPs), there is increasing concern regarding MPs-induced contamination in soil ecological systems. Notwithstanding, the interaction between the plastisphere and rhizosphere microbial hotspots in soil-plant systems, as well as the diversity and composition of plastisphere microbial communities in such systems, remain largely unexplored. This study evaluated the response of rhizosphere bacterial communities to MPs at three growth stages of pepper and examined the bacterial communities present on MPs (plastisphere). The 16 S rRNA revealed that, under the stress of MPs, the Chao1 and Shannon index of the pepper soil bacterial community decreased. Meanwhile the relative abundance of Actinobacteriota was decreased, and that of Proteobacteria was increased. Furthermore, the plastisphere serves as a unique microbial habitat (niche) that recruits the colonization of specific bacterial groups, including potential plastic-degrading bacteria and potential pathogens (e.g., Massilia and Pseudomonas). Simultaneously, the plastisphere recruits specific bacteria that may impact the rhizosphere soil bacterial communities, thus indirectly affecting plant growth. Functional prediction using PICRUSt2 revealed higher activity in the plastisphere for Metabolism of terpenoids and polyketides, Human diseases, and Xenobiotics biodegradation and metabolism. Notably, the human diseases metabolic pathway exhibited increased activity, suggesting potential ecological risks associated with pathogens. These results highlighted that the plastisphere serves as a unique microbial habitat (niche) in the soil ecological systems, recruiting specific bacteria and potentially interfering with the surrounding soil microbial community, thereby influencing the functional characteristics of the soil ecological systems.


Assuntos
Capsicum , Solo , Humanos , Plásticos , Rizosfera , Microbiologia do Solo , Bactérias/genética , Microplásticos
12.
Ann Med Surg (Lond) ; 86(1): 336-344, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38222697

RESUMO

Background: The COVID-19 pandemic has caused over 656 million confirmed cases and over 6.6 million deaths worldwide. Chronic kidney disease (CKD) is considered a high-risk factor for COVID-19; therefore, considerable research has been conducted in this field. Therefore, this study aims to conduct a bibliometric analysis of publications related to COVID-19 and CKD. Methods: Publications were retrieved from the Web of Science Core Collection database on 16 January 2023 and screened based on inclusion criteria. Then the authors used Microsoft Excel and CiteSpace to analyze the included publications from the following seven aspects: countries/regions, institutions, journals, authors, cited references, and keywords. Results: In total, 622 publications were included in the study. The USA has the most publications in this field, followed by China. The Icahn School of Medicine at Mount Sinai and Harvard Medical School had the highest number of publications in the field. Journal of Clinical Medicine had the largest number of publications, and Lancet was the most cited journal. Alberto Ortiz was the author with the largest number of publications, but there were no influential authors in this field. The highly cited references are mainly clinical studies on COVID-19. Research hotspots in this field include end-stage recent disease, cardiovascular disease, kidney metastasis, diabetes Mellitus, acute kidney injury, meta-analysis, and consistent plasma. Conclusions: The USA, China, and some European countries and their institutions are major contributors to these publications. End-stage renal disease, acute kidney injury, kidney transplantation and convalescent plasma are current hot topics in the field.

13.
Nat Commun ; 15(1): 496, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216571

RESUMO

We report an organocatalyst that combines a triazolium N-heterocyclic carbene (NHC) with a squaramide as a hydrogen-bonding donor (HBD), which can effectively catalyze the atroposelective ring-opening of biaryl lactams via a unique amide C-N bond cleavage mode. The free carbene species attacks the amide carbonyl, forming an axially chiral acyl-azolium intermediate. Various axially chiral biaryl amines can be accessed by this methodology with up to 99% ee and 99% yield. By using mercaptan as a catalyst turnover agent, the resulting thioester synthon can be transformed into several interesting atropisomers. Both control experiments and theoretical calculations reveal the crucial role of the hybrid NHC-HBD skeleton, which activates the amide via H-bonding and brings it spatially close to the carbene centre. This discovery illustrates the potential of the NHC-HBD chimera and demonstrates a complementary strategy for amide bond activation and manipulation.

14.
Int Immunopharmacol ; 128: 111499, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38232535

RESUMO

BACKGROUND AND AIMS: S100a10 is a member of the S100 family of proteins, which plays a key role in the depression and tumor metastasis. However, the role of S100a10 is unclear in ulcerative colitis. METHODS: The effect of S100a10 was assessed using a murine ulcerative colitis model which was accompanied by parameters including body weight loss, disease activity index, histological score, colon weight and length. The quantity and role of immune cells was determined by flow cytometry and bone marrow chimeric mice. Neutrophils depletion, adoptive cell transfer and conditional knockout mice were used to ascertain which cells played the key role in ulcerative colitis. The function of neutrophils was evaluated by migration assay, phagocytosis assay, multiplex immunoassay and real-time PCR. RESULTS: In this study, our data showed that S100a10-/- mice were prone to ulcerative colitis induced by dextran sodium sulfate. Neutrophils number increased in colon of S100a10-/- mice after dextran sodium sulfate treatment significantly. Meanwhile, adoptive transfer of neutrophils from wild type mice partially decreased the susceptibility of S100a10-/- mice to dextran sodium sulfate. There was no difference in ulcerative colitis between the groups of S100a10-/- mice without neutrophils and wild type mice. Finally, we found that S100a10-/- neutrophils had stronger function in secretion and synthesis of inflammatory factor. CONCLUSIONS: In one word, these results suggest that S100a10 has a role in inhibiting the pathogenesis of ulcerative colitis through regulation of neutrophils function.


Assuntos
Colite Ulcerativa , Colite , Sulfatos , Animais , Camundongos , Colite/induzido quimicamente , Colite Ulcerativa/patologia , Colo/patologia , Sulfato de Dextrana/farmacologia , Dextranos/efeitos adversos , Dextranos/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/metabolismo
15.
Sci Total Environ ; 914: 169913, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38185167

RESUMO

This study investigated the influence of biomass addition on the denitrification performance of iron-carbon wetlands. During long-time operation, the effluent NO3--N concentration of CW-BFe was observed to be the lowest, registering at 0.418 ± 0.167 mg/L, outperforming that of CW-Fe, which recorded 1.467 ± 0.467 mg/L. However, the effluent NH4+-N for CW-BFe increased to 1.465 ± 0.121 mg/L, surpassing CW-Fe's 0.889 ± 0.224 mg/L. Within a typical cycle, when establishing first-order reaction kinetics based on NO3--N concentrations, the introduction of biomass was found to amplify the kinetic constants across various stages in the iron-carbon wetland, ranging between 2.4 and 5.4 times that of CW-Fe. A metagenomic analysis indicated that biomass augments the reduction of NO3--N and NO2--N nitrogen and significantly bolsters the dissimilation nitrate reduction to ammonia pathway. Conversely, it impedes the reduction of N2O, leading to a heightened proportion of 2.715 % in CW-BFe's nitrogen mass balance, a stark contrast to CW-Fe's 0.379 %.


Assuntos
Nitratos , Áreas Alagadas , Desnitrificação , Amônia , Biomassa , Carbono , Ferro , Nitrogênio/análise , Eliminação de Resíduos Líquidos
16.
Ecotoxicol Environ Saf ; 271: 115962, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38237394

RESUMO

High-precision mapping based on portable X-ray fluorescence (PXRF) data is currently being studied extensively; however, owing to poor correlation with soil metal concentration, the original PXRF data directly used for co-kriging interpolation (CKI) cannot accurately map contaminated sites with heterogeneous concentrations. Therefore, this study selected a landfill-contaminated site for research, explored the best correlation mode between PXRF variants and actual heavy metal concentration, analyzed the impact of improving the correlation model on the CKI of the spatial distribution of heavy metals, and explored the most appropriate CKI mode and point density. The results showed the following: (1) After nonlinear transformation, the correlation model between PXRF and the actual concentration was significantly improved, and the correlation coefficients of five heavy metals increased from 0.214-0.232 to 0.936-0.986. (2) The introduction of corrected PXRF data significantly improves the accuracy of CKI. Compared with the original PXRF co-kriging interpolation (OP-CKI), the ME of the corrected PXRF co-kriging interpolation (CP-CKI) for Zn, Pb, and Cu decreased by 78.2 %, 45.5 %, and 65.3 %, respectively. In terms of the spatial distribution of heavy metal pollutant concentrations, CP-CKI effectively improved the influence of local anomalous high-value points on the interpolation accuracy. (3) When the sample density measured by inductively coupled plasma mass spectrometry (ICP-MS) was less than 4 boreholes/hm2, CKI accuracy decreased significantly, indicating that the sample density should not be less than a certain threshold during CKI. (4) When the sample density measured by PXRF exceeded 7 boreholes/hm2, the mean error and root mean square error of CKI continued to decrease, suggesting that the introduction of enough sample density measured by PXRF can effectively improve the accuracy of CKI.


Assuntos
Metais Pesados , Poluentes do Solo , Raios X , Espectrometria por Raios X/métodos , Poluentes do Solo/análise , Monitoramento Ambiental/métodos , Metais Pesados/análise , Análise Espacial , Solo/química
17.
Anal Methods ; 16(2): 301-313, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38115807

RESUMO

Rapid and accurate detection of hydrolyzed products of organophosphorus nerve agents (OPNAs) is an important method to effectively confirm the use of these agents. OPNAs are rapidly hydrolyzed to the methyl phosphonates (MPs) in the environment, which can be used as environmental traceability marker for OPNAs. Herein, magnetic mesoporous materials combined with real-time in situ mass spectrometry (MS) were used to achieve high-throughput detection of MPs. Novel magnetic mesoporous nanoparticles Fe3O4@nSiO2@mSiO2 were synthesized via co-condensation of tetraethyl orthosilicate and cetyltrimethylammonium bromide (CTAB) on the surface of nonporous silica-coated Fe3O4 under alkaline conditions. CTAB templates were removed by the reflux of ethanol (0.0375 mM ammonium nitrate) to form mesoporous SiO2, which has a large specific surface area of 549 m2 g-1 and an excellent magnetization strength of 59.6 emu g-1. A quick, cost-effective, rugged, and safe magnetic preparation method, magnetic QuEChERS, was established with magnetic mesoporous nanoparticles (Fe3O4@nSiO2@mSiO2) as adsorption materials for direct analysis in real-time and tandem MS (DART-MS/MS) of MPs in environmental samples. The method exhibits good linearity (R2 > 0.992) in the range of 20.0-4.00 µg mL-1, the limits of detection were <5.00 ng mL-1, the limits of quantification were <20.0 ng mL-1, and the extraction recoveries were 70.2-98.1%, with relative standard deviations (RSDs) in the range of 1.97-10.6%. Additionally, using this method, analysis of 70 environmental samples could be completed within 20 min. Then, the M-QuEChERS-DART-MS/MS method was applied to the 52nd Organisation for the Prohibition of Chemical Weapons (OPCW) environmental spiked samples analysis, where the accuracy was 95.2-116%, and the RSD was 1.16-7.83%. The results demonstrated that Fe3O4@nSiO2@mSiO2 based on the QuEChERS method can quickly and efficiently remove the matrix of environmental samples and when coupled with the DART-MS/MS can achieve high-throughput determination of MPs in environmental samples.

18.
J Am Chem Soc ; 146(5): 2967-2976, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38155548

RESUMO

Cobalt-based spinel oxides (i.e., Co3O4) are emerging as low-cost and selective electrocatalysts for the electrochemical nitrate reduction reaction (NO3-RR) to ammonia (NH3), although their activity is still unsatisfactory and the genuine active site is unclear. Here, we discover that the NO3-RR activity of Co3O4 is highly dependent on the geometric location of the Co site, and the NO3-RR prefers to occur at octahedral Co (CoOh) rather than tetrahedral Co (CoTd) sites. Moreover, CoOhO6 is electrochemically transformed to CoOhO5 along with the formation of O vacancies (Ov) during the process of NO3-RR. Both experimental and theoretic results reveal that in situ generated CoOhO5-Ov configuration is the genuine active site for the NO3-RR. To further enhance the activity of CoOh sites, we replace inert CoTd with different contents of Cu2+ cations, and a volcano-shape correlation between NO3-RR activity and electronic structures of CoOh is observed. Impressively, in 1.0 M KOH, (Cu0.6Co0.4)Co2O4 with optimized CoOh sites achieves a maximum NH3 Faradaic efficiency of 96.5% with an ultrahigh NH3 rate of 1.09 mmol h-1 cm-2 at -0.45 V vs reversible hydrogen electrode, outperforming most of other reported nonprecious metal-based electrocatalysts. Clearly, this work paves new pathways for boosting the NO3-RR activity of Co-based spinels by tuning local electronic structures of CoOh sites.

19.
Front Physiol ; 14: 1277942, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37954450

RESUMO

Aphidoletes aphidimyza is a predator that is an important biological agent used to control agricultural and forestry aphids. Although many studies have investigated its biological and ecological characteristics, few molecular studies have been reported. The current study was performed to identify suitable reference genes to facilitate future gene expression and function analyses via quantitative reverse transcription PCR. Eight reference genes glyceraldehyde-3-phosphate dehydrogenase (GAPDH), RPS13, RPL8, RPS3, α-Tub, ß-actin, RPL32, and elongation factor 1 alpha (EF1-α) were selected. Their expression levels were determined under four different experimental conditions (developmental stages, adult tissues, sugar treatment, and starvation treatment) using qRT-PCR technology. The stability was evaluated with five methods (Ct value, geNorm, NormFinder, BestKeeper, and RefFinder). The results showed that GAPDH, RPL32, and EF1-α were ranked as the best reference gene combinations for measuring gene expression levels among different developing stages and in various starvation treatments. RPL8 and RPS3 were recommended to normalize the gene expression levels among different adult tissues. RPL32, ß-actin, and EF1-α were recommended sugar-feeding conditions. To validate the utility of the selected reference pair, RPL8, and RPS3, we estimated the tissue-biased expression level of a chemosensory protein gene (AaphCSP1). As expected, AaphCSP1 is highly expressed in the antennae and lowly expressed in the abdomen. These findings will lay the foundation for future research on the molecular physiology and biochemistry of A. aphidimyza.

20.
Nat Commun ; 14(1): 7797, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38016984

RESUMO

Plant-sourced aromatic amino acid (AAA) derivatives are a vast group of compounds with broad applications. Here, we present the development of a yeast consortium for efficient production of (S)-norcoclaurine, the key precursor for benzylisoquinoline alkaloid biosynthesis. A xylose transporter enables the concurrent mixed-sugar utilization in Scheffersomyces stipitis, which plays a crucial role in enhancing the flux entering the highly regulated shikimate pathway located upstream of AAA biosynthesis. Two quinate permeases isolated from Aspergillus niger facilitates shikimate translocation to the co-cultured Saccharomyces cerevisiae that converts shikimate to (S)-norcoclaurine, resulting in the maximal titer (11.5 mg/L), nearly 110-fold higher than the titer reported for an S. cerevisiae monoculture. Our findings magnify the potential of microbial consortium platforms for the economical de novo synthesis of complex compounds, where pathway modularization and compartmentalization in distinct specialty strains enable effective fine-tuning of long biosynthetic pathways and diminish intermediate buildup, thereby leading to increases in production.


Assuntos
Benzilisoquinolinas , Xilose , Xilose/metabolismo , Benzilisoquinolinas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Consórcios Microbianos , Engenharia Metabólica/métodos , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo
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