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Antibiotics typically induce major physiological changes in bacteria. However, their effect on nutrient consumption remains unclear. Here we found that Escherichia coli communities can sustain normal levels of glucose consumption under a broad range of antibiotics. The community-living resulted in a low membrane potential in the bacteria, allowing slow antibiotic accumulation on treatment and better adaptation. Through multi-omics analysis, we identified a prevalent adaptive response characterized by the upregulation of lipid synthesis, which substantially contributes to sustained glucose consumption. The consumption was maintained by the periphery region of the community, thereby restricting glucose penetration into the community interior. The resulting spatial heterogeneity in glucose availability protected the interior from antibiotic accumulation in a membrane potential-dependent manner, ensuring rapid recovery of the community postantibiotic treatment. Our findings unveiled a community-level antibiotic response through spatial regulation of metabolism and suggested new strategies for antibiotic therapies.
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Microbial communities often display region-specific properties, which give rise to complex interactions and emergent behaviors that are critical to the homeostasis and stress response of the communities. However, systems-level understanding of these properties still remains elusive. In this study, we established RAINBOW-seq and profiled the transcriptome of Escherichia coli biofilm communities with high spatial resolution and high gene coverage. We uncovered three modes of community-level coordination, including cross-regional resource allocation, local cycling and feedback signaling, which were mediated by strengthened transmembrane transport and spatially specific activation of metabolism. As a consequence of such coordination, the nutrient-limited region of the community maintained an unexpectedly high level of metabolism, enabling it to express many signaling genes and functionally unknown genes with potential sociality functions. Our work provides an extended understanding of the metabolic interplay in biofilms and presents a new approach of investigating complex interactions in bacterial communities on the systems level.
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Escherichia coli K12 , Escherichia coli K12/genética , Escherichia coli/genética , Transcriptoma , Biofilmes , Bactérias/genéticaRESUMO
BACKGROUND: Iron plays a crucial role in the growth of Mycobacterium tuberculosis (M. tuberculosis). However, the precise regulatory mechanism governing this system requires further elucidation. Additionally, limited studies have examined the impact of gene mutations related to iron on the transmission of M. tuberculosis globally. This research aims to investigate the correlation between mutations in iron-related genes and the worldwide transmission of M. tuberculosis. RESULTS: A total of 13,532 isolates of M. tuberculosis were included in this study. Among them, 6,104 (45.11%) were identified as genomic clustered isolates, while 8,395 (62.04%) were classified as genomic clade isolates. Our results showed that a total of 12 single nucleotide polymorphisms (SNPs) showed a positive correlation with clustering, such as Rv1469 (ctpD, C758T), Rv3703c (etgB, G1122T), and Rv3743c (ctpJ, G676C). Additionally, seven SNPs, including Rv0104 (T167G, T478G), Rv0211 (pckA, A302C), Rv0283 (eccB3, C423T), Rv1436 (gap, G654T), ctpD C758T, and etgB C578A, demonstrated a positive correlation with transmission clades across different countries. Notably, our findings highlighted the positive association of Rv0104 T167G, pckA A302C, eccB3 C423T, ctpD C758T, and etgB C578A with transmission clades across diverse regions. Furthermore, our analysis identified 78 SNPs that exhibited significant associations with clade size. CONCLUSIONS: Our study reveals the link between iron-related gene SNPs and M. tuberculosis transmission, offering insights into crucial factors influencing the pathogenicity of the disease. This research holds promise for targeted strategies in prevention and treatment, advancing research and interventions in this field.
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Mycobacterium tuberculosis , Tuberculose , Humanos , Mycobacterium tuberculosis/genética , Sequenciamento Completo do Genoma , Ferro , Mutação , Tuberculose/genéticaRESUMO
BACKGROUND: The respiratory chain plays a key role in the growth of Mycobacterium tuberculosis complex (MTBC). However, the exact regulatory mechanisms of this system still need to be elucidated, and only a few studies have investigated the impact of genetic mutations within the respiratory chain on MTBC transmission. This study aims to explore the impact of respiratory chain gene mutations on the global spread of MTBC. RESULTS: A total of 13,402 isolates of MTBC were included in this study. The majority of the isolates (n = 6,382, 47.62%) belonged to lineage 4, followed by lineage 2 (n = 5,123, 38.23%). Our findings revealed significant associations between Single Nucleotide Polymorphisms (SNPs) of specific genes and transmission clusters. These SNPs include Rv0087 (hycE, G178T), Rv1307 (atpH, C650T), Rv2195 (qcrA, G181C), Rv2196 (qcrB, G1250T), Rv3145 (nuoA, C35T), Rv3149 (nuoE, G121C), Rv3150 (nuoF, G700A), Rv3151 (nuoG, A1810G), Rv3152 (nuoH, G493A), and Rv3157 (nuoM, A1243G). Furthermore, our results showed that the SNPs of atpH C73G, atpA G271C, qcrA G181C, nuoJ G115A, nuoM G772A, and nuoN G1084T were positively correlated with cross-country transmission clades and cross-regional transmission clades. CONCLUSIONS: Our study uncovered an association between mutations in respiratory chain genes and the transmission of MTBC. This important finding provides new insights for future research and will help to further explore new mechanisms of MTBC pathogenicity. By uncovering this association, we gain a more complete understanding of the processes by which MTBC increases virulence and spread, providing potential targets and strategies for preventing and treating tuberculosis.
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Mutação , Mycobacterium tuberculosis , Polimorfismo de Nucleotídeo Único , Tuberculose , Mycobacterium tuberculosis/genética , Tuberculose/microbiologia , Tuberculose/genética , Tuberculose/transmissão , Humanos , Transporte de Elétrons/genética , Proteínas de Bactérias/genéticaRESUMO
Here, we describe a cooperative Pd(0)/chiral phosphoric acid catalytic system that allows us to realize the first chemo-, regio-, and enantioselective sequential cross-[4 + 2]-cycloaddition/decarboxylation reaction between 2-pyrones and unactivated acyclic 1,3-dienes. The key to the success of this transformation is the utilization of an achiral N-heterocyclic carbene (NHC) as the ligand and a newly developed chiral phosphoric acid as the cocatalyst. Experimental investigations and computational studies support the idea that the Pd(0)/NHC complex acts as a π-Lewis base to increase the nucleophilicity of 1,3-dienes via η2 coordination, while the chiral phosphoric acid simultaneously increases the electrophilicity of 2-pyrones by hydrogen bonding. By this synergistic catalysis, the sequential cross-[4 + 2]-cycloaddition and decarboxylation reaction proceeds efficiently, enabling the preparation of a wide range of chiral vinyl-substituted 1,3-cyclohexadienes in good yields and enantioselectivities. The synthetic utility of this reaction is demonstrated by synthetic transformations of the product to various valuable chiral six-membered carbocycles.
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Accurate coordination of chromosome replication and cell division is essential for cellular processes, yet the regulatory mechanisms governing the bacterial cell cycle remain contentious. The lack of quantitative data connecting key cell cycle players at the single-cell level across large samples hinders consensus. Employing high-throughput flow cytometry, we quantitatively correlated the expression levels of key cell cycle proteins (FtsZ, MreB, and DnaA) with DNA content in individual bacteria. Our findings reveal distinct correlations depending on the chromosome number (CN), specifically whether CN ≤2 or ≥4, unveiling a mixed regulatory scenario in populations where CN of 2 or 4 coexist. We observed function-dependent regulations for these key proteins across nonoverlapping division cycles and various nutrient conditions. Notably, a logarithmic relationship between total protein content and replication origin number across nutrient conditions suggests a unified mechanism governing cell cycle progression, confirming the applicability of Schaechter's growth law to cells with CN ≥4. For the first time, we established a proportional relationship between the synthesis rates of key cell cycle proteins and chromosome dynamics in cells with CN ≥4. Drug experiments highlighted CN 2 and 4 as pivotal turning points influencing cellular resource allocation. This high-throughput, single-cell analysis provides interconnected quantitative insights into key molecular events, facilitating a predictive understanding of the relationship between cell growth and cell cycle.
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In this work, a mitochondria-targeted NIR ratiometric and colorimetric fluorescent probe 1 was tactfully designed and synthesized by a novel design strategy of modifying chromene to pyridine for the first time. 1 exhibited a maximum absorption peak at 508 nm and a maximum fluorescence emission peak at 650 nm. Under the stimulus of biothiols (cysteine (Cys), homocysteine (Hcy), and glutathione (GSH)), the maximum absorption and fluorescence emission peaks of 1 blue-shifted to 448 and 541 nm, respectively, along with color changes from red to yellow under visible light and from red to green under a 365 nm ultraviolet (UV) lamp, which can be ascribed to the click reaction of biothiols with the α,ß-unsaturated ketone of the chromene moiety with pyran ring-opening, phenol formation, and 1,6-elimination of the p-hydroxybenzyl moiety. 1 detected biothiols (Cys, GSH, and Hcy) with high sensitivity (LODs of 29, 23, and 16 nM for Cys, GSH, and Hcy, respectively), excellent selectivity, and fast response. Moreover, 1 can target mitochondria and image the fluctuation of intracellular biothiols by dual-emission channels.
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To explore novel electrode materials with in-depth elucidation of initial coulombic efficiency (ICE), kinetics, and charge storage mechanisms is of great challenge for Na-ion storage. Herein, a novel 3D antiperovskite carbide Ni3ZnC0.7@rGO anode coupled with ether-based electrolyte is reported for fast Na-ion storage, exhibiting superior performance than ester-based electrolyte. Electrochemical tests and density functional theory (DFT) calculations show that Ni3ZnC0.7@rGO anode with ether-based electrolyte can promote charge/ion transport and lower Na+ diffusion energy barrier, thereby improving ICE, reversible capacity, rate, and cycling performance. Cross-sectional-morphology and depth profiling surface chemistry demonstrate that not only a thinner and more homogeneous reaction interface layer with less side effects but also a superior solid electrolyte interface (SEI) film with a high proportion of inorganic components are formed in the ether-based electrolyte, which accelerates Na+ transport and is the significant reason for the improvement of ICE and other electrochemical properties. Meanwhile, electrochemical and ex situ measurements have revealed conversion, alloying, and co-intercalation hybrid mechanisms of the Ni3ZnC0.7@rGO anode based on ether electrolyte. Interestingly, the Na-ion capacitors (SICs) designed by pairing with activated carbon (AC) cathode exhibit favorable electrochemical performance. Overall, this work provides deep insights on developing advanced materials for fast Na-ion storage.
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Developing high electroactivity ruthenium (Ru)-based electrocatalysts for pH-universal hydrogen evolution reaction (HER) is challenging due to the strong bonding strengths of key RuâH/RuâOH intermediates and sluggish water dissociation rates on active Ru sites. Herein, a semi-ionic F-modified N-doped porous carbon implanted with ruthenium nanoclusters (Ru/FNPC) is introduced by a hydrogel sealing-pyrolying-etching strategy toward highly efficient pH-universal hydrogen generation. Benefiting from the synergistic effects between Ru nanoclusters (Ru NCs) and hierarchically F, N-codoped porous carbon support, such synthesized catalyst displays exceptional HER reactivity and durability at all pH levels. The optimal 8Ru/FNPC affords ultralow overpotentials of 17.8, 71.2, and 53.8 mV at the current density of 10 mA cm-2 in alkaline, neutral, and acidic media, respectively. Density functional theory (DFT) calculations elucidate that the F-doped substrate to support Ru NCs weakens the adsorption energies of H and OH on Ru sites and reduces the energy barriers of elementary steps for HER, thus enhancing the intrinsic activity of Ru sites and accelerating the HER kinetics. This work provides new perspectives for the design of advanced electrocatalysts by porous carbon substrate implanted with ultrafine metal NCs for energy conversion applications.
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OBJECTIVE: This study aims to examine the impact of PE/PPE gene mutations on the transmission of Mycobacterium tuberculosis (M. tuberculosis) in China. METHODS: We collected the whole genome sequencing (WGS) data of 3202 M. tuberculosis isolates in China from 2007 to 2018 and investigated the clustering of strains from different lineages. To evaluate the potential role of PE/PPE gene mutations in the dissemination of the pathogen, we employed homoplastic analysis to detect homoplastic single nucleotide polymorphisms (SNPs) within these gene regions. Subsequently, logistic regression analysis was conducted to analyze the statistical association. RESULTS: Based on nationwide M. tuberculosis WGS data, it has been observed that the majority of the M. tuberculosis burden in China is caused by lineage 2 strains, followed by lineage 4. Lineage 2 exhibited a higher number of transmission clusters, totaling 446 clusters, of which 77 were cross-regional clusters. Conversely, there were only 52 transmission clusters in lineage 4, of which 9 were cross-regional clusters. In the analysis of lineage 2 isolates, regression results showed that 4 specific gene mutations, PE4 (position 190,394; c.46G > A), PE_PGRS10 (839,194; c.744 A > G), PE16 (1,607,005; c.620T > G) and PE_PGRS44 (2,921,883; c.333 C > A), were significantly associated with the transmission of M. tuberculosis. Mutations of PE_PGRS10 (839,334; c.884 A > G), PE_PGRS11 (847,613; c.1455G > C), PE_PGRS47 (3,054,724; c.811 A > G) and PPE66 (4,189,930; c.303G > C) exhibited significant associations with the cross-regional clusters. A total of 13 mutation positions showed a positive correlation with clustering size, indicating a positive association. For lineage 4 strains, no mutations were found to enhance transmission, but 2 mutation sites were identified as risk factors for cross-regional clusters. These included PE_PGRS4 (338,100; c.974 A > G) and PPE13 (976,897; c.1307 A > C). CONCLUSION: Our results indicate that some PE/PPE gene mutations can increase the risk of M. tuberculosis transmission, which might provide a basis for controlling the spread of tuberculosis.
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Mutação , Mycobacterium tuberculosis , Polimorfismo de Nucleotídeo Único , Tuberculose , Sequenciamento Completo do Genoma , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/isolamento & purificação , China/epidemiologia , Humanos , Tuberculose/transmissão , Tuberculose/microbiologia , Tuberculose/epidemiologia , Genoma Bacteriano , Feminino , Masculino , Proteínas de Bactérias/genética , AdultoRESUMO
BACKGROUND: The American Heart Association (AHA) has recently introduced the concept of Cardiovascular-Kidney-Metabolic (CKM) syndrome, which is the result of an increasing emphasis on the interplay of metabolic, renal and cardiovascular diseases (CVD). Furthermore, there is substantial evidence of a correlation between the triglyceride glucose-body mass index (TyG-BMI ) and CVD as an assessment of insulin resistance (IR). However, it remains unknown whether this correlation exists in population with CKM syndrome. METHODS: All data for this study were obtained from the China Health and Retirement Longitudinal Study (CHARLS). The exposure was the participants' TyG-BMI at baseline, which was calculated using a combination of triglycerides (TG), fasting blood glucose (FBG) and body mass index (BMI). The primary outcome was CVD, which were determined by the use of a standardised questionnaire during follow-up. To examine the relationship between TyG-BMI and CVD incidence in population with CKM syndrome, both Cox regression analyses and restricted cubic spline (RCS) regression analyses were performed. RESULTS: A total of 7376 participants were included in the final analysis. Of these, 1139, 1515, 1839, and 2883 were in CKM syndrome stages 0, 1, 2, and 3, respectively, at baseline. The gender distribution was 52.62% female, and the mean age was 59.17 ± 9.28 (years). The results of the fully adjusted COX regression analyses indicated that there was a 6.5% increase in the risk of developing CVD for each 10-unit increase in TyG-BMI,95% confidence interval (CI):1.041-1.090. The RCS regression analyses demonstrated a positive linear association between TyG-BMI and the incidence of CVD in the CKM syndrome population (P for overall < 0.001, P for nonlinear = 0.355). CONCLUSIONS: This cohort study demonstrated a positive linear association between TyG-BMI index and increased CVD incidence in a population with CKM syndrome stage 0-3. This finding suggests that enhanced assessment of TyG-BMI index may provide a more convenient and effective tool for individuals at risk for CVD in CKM syndrome stage 0-3.
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Biomarcadores , Glicemia , Índice de Massa Corporal , Doenças Cardiovasculares , Síndrome Metabólica , Triglicerídeos , Humanos , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/sangue , Estudos Prospectivos , Medição de Risco , Triglicerídeos/sangue , Incidência , Idoso , China/epidemiologia , Glicemia/metabolismo , Fatores de Tempo , Biomarcadores/sangue , Prognóstico , Nefropatias/epidemiologia , Nefropatias/diagnóstico , Nefropatias/sangue , Estudos Longitudinais , Fatores de Risco de Doenças Cardíacas , Resistência à Insulina , Fatores de RiscoRESUMO
Wood density is a fundamental property related to tree biomechanics and hydraulic function while playing a crucial role in assessing vegetation carbon stocks by linking volumetric retrieval and a mass estimate. This study provides a high-resolution map of the global distribution of tree wood density at the 0.01° (~1 km) spatial resolution, derived from four decision trees machine learning models using a global database of 28,822 tree-level wood density measurements. An ensemble of four top-performing models combined with eight cross-validation strategies shows great consistency, providing wood density patterns with pronounced spatial heterogeneity. The global pattern shows lower wood density values in northern and northwestern Europe, Canadian forest regions and slightly higher values in Siberia forests, western United States, and southern China. In contrast, tropical regions, especially wet tropical areas, exhibit high wood density. Climatic predictors explain 49%-63% of spatial variations, followed by vegetation characteristics (25%-31%) and edaphic properties (11%-16%). Notably, leaf type (evergreen vs. deciduous) and leaf habit type (broadleaved vs. needleleaved) are the most dominant individual features among all selected predictive covariates. Wood density tends to be higher for angiosperm broadleaf trees compared to gymnosperm needleleaf trees, particularly for evergreen species. The distributions of wood density categorized by leaf types and leaf habit types have good agreement with the features observed in wood density measurements. This global map quantifying wood density distribution can help improve accurate predictions of forest carbon stocks, providing deeper insights into ecosystem functioning and carbon cycling such as forest vulnerability to hydraulic and thermal stresses in the context of future climate change.
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Ecossistema , Madeira , Canadá , Florestas , Folhas de Planta , CarbonoRESUMO
Chromene as the efficient biothiol recognition site was widely used to develop fluorescent probes based on thiol-chromene click reaction. However, chromene-based fluorescent probes with the both properties of ratiometric measurement and mitochondria-targeted function have not been reported and remain challenging. In this paper, we skillfully designed and synthesized the first mitochondria-targeted ratiometric fluorescent probe (Probe 1) for biothiols based on chromene. Upon addition of biothiols (Cys, Hcy, and GSH), the absorption and fluorescence spectra of Probe 1 changed from 490 to 426 nm and from 567 to 498 nm respectively, accompanied by color changes from orange to pale yellow under natural light and from orange to blue under a 365-nm UV lamp, which can be attributed to the click reaction of biothiols with α,ß-unsaturated ketone of chromene moiety, subsequent pyran ring-opening, and phenol formation as well as 1,6-elimination of p-hydroxybenzyl moiety. Probe 1 not only exhibited high sensitivity (LODs of 149 nM, 133 nM, and 116 nM for Cys, GSH, and Hcy respectively), rapid response, and excellent selectivity for biothiols (Cys, Hcy, and GSH), but also could target in mitochondria and ratiometrically image the fluctuation of intracellular biothiols. Moreover, the novel design strategy of modifying chromene to the N atom of pyridine was proposed for the first time.
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Swab sampling is a common method for recovering microbes on various environmental surfaces. Its successful application for a specific target depends on the proper swab method and the following detection assay. Herein, we evaluated critical factors influencing surface swab sampling, aiming to achieve the optimal detection and quantification performance of optical detection for bacterial cells on stainless-steel surfaces. Our results showed the recovery rate of Salmonella enterica (SE1045) cells from the 10 × 10 cm2 stainless-steel surface reached up to 92.71 ± 2.19% when using ammonia bicarbonate-moistened polyurethane foam swabs for gentle collection, followed by ultrasound-assisted release in NH4HCO3 solution. Among the six different foam swabs, the Puritan™ Sterile Large Foam Swab contributed the lowest background noise and highest recovery efficiency when integrated with the optical detection assay. Notably, our method exhibited a strong linear relationship (r2 = 0.9983) between the detected cell numbers and the theoretical number of SE1045 cells seeded on surfaces in the range of 104-107 Colony Forming Units (CFU), with a limit of detection of 7.2 × 104 CFU 100 cm-2. This integration was completed within 2 h, exhibiting the applicable potential in various settings.
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Salmonella enterica , Aço Inoxidável , Salmonella enterica/isolamento & purificação , Microscopia/métodos , Manejo de Espécimes/métodosRESUMO
Designing solid polymer electrolytes (SPEs) with high ionic conductivity for room-temperature operation is essential for advancing flexible all-solid-state energy storage devices. Innovative strategies are urgently required to develop SPEs that are safe, stable, and high-performing. In this work, we introduce photoexcitation-modulated heterojunctions as catalytically active fillers within SPEs, guided by photocatalytic design principles, and employ natural bacterial cellulose to enhance the mechanical properties of the inorganic-filled SPEs. In-situ photothermal experiments and theoretical calculations reveal that the strong photogenerated electric field produced by trace heterojunctions within poly(ethylene oxide) electrolytes under photoexcitation significantly enhances lithium salt dissociation, increasing the concentration of mobile Li+. This results in a substantial increase in ionic conductivity, reaching 0.135 mS cm-1 at 25 °C, with a Li+ transference number as high as 0.46. The flexible all-solid-state lithium-metal pouch cells exhibit an impressive discharge capacity of 178.8 mAh g-1 even after repeated bending and folding, and demonstrate exceptional long-term cycling stability, retaining 86.7% of their initial capacity after 250 cycles at 1 C (25 °C). This research offers a novel approach to developing high-performance flexible lithium-metal batteries.
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Aqueous Zn-based batteries (AZBs) have attracted intensive attention. However, to explore advanced cathode materials with in-depth elucidation of their charge storage mechanisms, improve energy storage capacity, and construct novel cell systems remain a great challenge. Herein, a new pseudocapacitive multiple perovskite fluorides (ABF3 ) cathode is designed, represented by KMF-(IV, V, and VI; M = NiCoMnZn/-Mg/-MgFe), and constructed Zn//KMF-(IV, V, and VI) AZBs and their flexible devices. Ex situ tests have revealed a typical bulk phase conversion mechanism of KMF-VI electrode for charge storage in alkaline media dominated by redox-active Ni/Co/Mn species, with transformation of ABF3 nanocrystals into amorphous metal oxide/(oxy)hydroxide nanosheets. By employing single or bipolar redox electrolyte strategies of 20 mm [Fe(CN)6 ]3- or/and 10 mm SO3 2- /Cu[(NH3 )4 ]2+ acting on KMF-(IV, V, and VI) cathode and Zn anode, the AZBs show an improved energy storage owing to additional capacity contribution of redox electrolytes. The as-designed Zn//polyvinyl alcohol (PVA)-KOH-K3 [Fe(CN)6 ]//KMF-(IV, V, and VI) redox gel electrolytes-assisting flexible AZBs (RGE-FAZBs) exhibit remarkable performance under different bending angles because of slight dissolution corrosion of zinc anode compared with liquid electrolytes. Overall, the work demonstrates the novel idea of conversion-type multiple ABF3 cathode for redox electrolytes-assisting AZBs (RE-AZBs) and their flexible systems, showing great significance on electrochemical energy storage.
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BACKGROUND: Fatty acid metabolism greatly promotes the virulence and pathogenicity of Mycobacterium tuberculosis (M.tb). However, the regulatory mechanism of fatty acid metabolism in M.tb remains to be elucidated, and limited evidence about the effects of gene mutations in fatty acid metabolism on the transmission of M.tb was reported. RESULTS: Overall, a total of 3193 M.tb isolates were included in the study, of which 1596 (50%) were genomic clustered isolates. Most of the tuberculosis isolates belonged to lineage2(n = 2744,85.93%), followed by lineage4(n = 439,13.75%) and lineage3(n = 10,0.31%).Regression results showed that the mutations of gca (136,605, 317G > C, Arg106Pro; OR, 22.144; 95% CI, 2.591-189.272), ogt(1,477,346, 286G > C ,Gly96Arg; OR, 3.893; 95%CI, 1.432-10.583), and rpsA (1,834,776, 1235 C > T, Ala412Val; OR, 3.674; 95% CI, 1.217-11.091) were significantly associated with clustering; mutations in gca and rpsA were also significantly associated with clustering of lineage2. Mutation in arsA(3,001,498, 885 C > G, Thr295Thr; OR, 6.278; 95% CI, 2.508-15.711) was significantly associated with cross-regional clusters. We also found that 20 mutation sites were positively correlated with cluster size, while 11 fatty acid mutation sites were negatively correlated with cluster size. CONCLUSION: Our research results suggested that mutations in genes related to fatty acid metabolism were related to the transmission of M.tb. This research could help in the future control of the transmission of M.tb.
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Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Humanos , Antituberculosos/farmacologia , Tuberculose/microbiologia , Sequenciamento Completo do Genoma , Mutação , Tuberculose Resistente a Múltiplos Medicamentos/microbiologiaRESUMO
BACKGROUND: Prognostic evaluation is important for personalized treatment in children with medulloblastoma (MB). Limited data are available for risk stratification using a radiomics-based model. PURPOSE: To evaluate the incremental value of an MRI radiomics signature in stratifying the risk of pediatric MB in terms of overall survival (OS). STUDY TYPE: Retrospective. SUBJECTS: A total of 111 children (mean age 5.82 years) with pathologically confirmed MB divided into training and validation cohorts (77 and 34 children, respectively). FIELD STRENGTH/SEQUENCE: A 3 T, contrast-enhanced T1-weighted imaging with inversion recovery. ASSESSMENT: The study endpoint was OS defined as the time between the preoperative MRI study and death or last follow-up. The radiomics signature model and a clinical-MRI model were developed for personalized OS prediction. An integrative model, which combined the radiomics signature and clinical-MRI features, was also built using multivariable Cox regression model. The performance of the three models was evaluated with the C-index. The performance of integrative model was assessed by calibration curve and decision curve analysis (DCA). STATISTICAL TESTS: Independent T-test, Mann-Whitney U test, Fisher's exact tests or chi-square test, logistic regression analysis, Kaplan-Meier survival analysis, C-index, intraclass correlation coefficients (ICC). P < 0.05 was considered statistically significant. RESULTS: The media OS was 2.83 years (3.87 ± 1.85 years). Two clinical and one conventional MR imaging features (remnant, adjuvant treatment, and peritumoral edema) were selected for clinical-MRI model building. The integrative model evaluated OS (C-index 0.823) better than either the radiomics signature (C-index 0.702) or the clinical-MRI model (C-index 0.771). And it also showed good performance in the validation cohort (C-indices: 0.786, 0.756, 0.721), which was validated by the good calibration (P > 0.05) and more benefit. DATA CONCLUSIONS: This study demonstrated that the integrative model, which combined radiomics signature, clinical, and conventional MRI features, showed best performance in OS evaluation for children with MB. The radiomics signature may confer incremental value over clinical-MRI features. EVIDENCE LEVEL: 3. TECHNICAL EFFICACY: Stage 2.
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Neoplasias Cerebelares , Meduloblastoma , Criança , Humanos , Pré-Escolar , Estudos Retrospectivos , Meduloblastoma/diagnóstico por imagem , Estudos de Coortes , Imageamento por Ressonância Magnética/métodos , Neoplasias Cerebelares/diagnóstico por imagem , Medição de RiscoRESUMO
Reasonable fertilization management can increase nutrient content and enzyme activity in rhizosphere soil, and even increase soil microbial richness. However, different fertilizers could raise distinct influences on the soil properties, including soil environmental factors (physicochemical properties and enzymatic activities) and microbial community. Here, the effects of two soil amendments (microbial fertilizer and woody peat) on environmental factors and microbial community structure in tobacco rhizosphere soil were evaluated, with the correlations between microbes and environmental factors explored. As the results, microbial fertilizer could effectively alleviate soil acidification, increase available potassium and organic matter contents in soil, and was also beneficial to increase nitrate reductase activity in rhizosphere soil. Fertilizers cause changes in the abundance of certain microbes in the soil. Besides, it was shown that the candidate phyla Gal15, Acidobacterota, Latescibacterota, Mortierellommycota, Basidiomycota, and Rozellomycota in tobacco rhizosphere soil had significant correlation with soil environmental factors. Through the functional analysis of these populations, it can be deduced that the changes in the abundance of certain microorganisms may be an important reason for the differences in environmental factors. All these indicated that the differences of environmental factors in different treatments are closely related to the abundance of some special soil microorganisms. Studying the life activities of these microbes would provide good guidance for exploring the interaction among crops, soil, and microorganisms and improving crop yields.
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Fertilizantes , Solo , Solo/química , Fertilizantes/análise , Nicotiana , Rizosfera , Microbiologia do SoloRESUMO
Reactive oxygen species (ROS)-induced element/pollutant geochemical processes in fluctuating anoxic-oxic areas have received increasing attention in recent years. Nitrous oxide (N2O) is a strong greenhouse gas; however, the relationship between ROS and N2O emissions in these areas has not been established. This work revealed the essential role of ROS in promoting N2O emissions in soil/sediment during the anoxic-oxic transition. ROS decreased the rate of nitrate reduction by 26-31% and increased N2O emissions by 8.8-31.3% (at 48 h). ROS-induced N2O emission was via inhibiting the step of N2O reduction. During the anoxic-oxic transition, the contribution of ROS to inhibit the step of N2O reduction was higher than 52.6%, demonstrating the important role of ROS. The downregulated relative transcription of the NosZ gene demonstrated inhibition at the gene level. Hydrogen peroxide was the dominant ROS species inhibiting N2O reduction, while the role of hydroxyl radicals was negligible, suggesting a different behavior of N2O emission with common pollutant conversion induced by ROS during the anoxic-oxic transition. This study demonstrated an overlooked factor in promoting N2O emission in the soil/sediment and appealed to a re-examination of the mechanism of N2O emissions in fluctuating anoxic-oxic areas.