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1.
Artigo em Inglês | MEDLINE | ID: mdl-39007716

RESUMO

Left ventricular (LV) hypertrophy (LVH) is frequently observed in patients with hypertension (HTN). LV myocardial work (MW) has recently emerged as a non-invasive method to assess systolic myocardial deformation relative to afterload conditions. The authors investigated the characteristics of myocardial work with different degrees of LVH in HTN patients. From December 2020 to February 2024, 255 HTN patients and 26 healthy controls undergoing transthoracic echocardiography were included in the current study. Hypertension patients were divided into quintile groups based on left ventricular mass index (LVMI), for the first to fourth LVMI quantiles, global work index (GWI) and global constructive work (GCW) were higher compared to the control group, but the difference was not statistically significant. In the sixth LVMI quantile, GWI and GCW showed a significant decrease. The restricted cubic splines showed that both GWI and GCW exhibited an inverted U-shaped relationship with LVMI. A LVMI of >151.39 g/m2 could accurately predict reduction both in GWI and GCW (Sensitivity: 0.78, Specificity: 0.89, AUC: 0.90, P < .001; Sensitivity: 0.81, Specificity: 0.92, AUC: 0.92, P < .001, respectively). As LVH progressed in HTN patients, both GWI and GCW initially demonstrated an increase, followed by a subsequent decrease. Myocardial work provides additional insights into assessment of cardiac function in HTN patients.

2.
J Control Release ; 373: 172-188, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-38972639

RESUMO

Ovarian cancer is one of the deadliest cancers, and combined chemo- and immunotherapies are potential strategies to combat it. However, the anti-cancer efficacy of the combined therapies may be limited by the non-selective co-delivery of chemotherapy and immunotherapy. Herein, a combined chemo- and immunotherapy is designed to selectively target ovarian tumor (ID8) cells and dendritic cells (DCs) using ID8 cell membrane (IM) and bacterial outer membrane vesicles (OMVs), respectively. Doxorubicin (DOX) and Ovalbumin (OVA) peptide (OVA257-264) are chosen as model chemotherapy and immunotherapy agents, respectively. A DNA nanocube capable of easily loading DOX or OVA257-264 is chosen as the carrier. Firstly, the DNA nanocube is used to load DOX or OVA257-264 to prepare cube-DOX or cube-OVA. This nanocube was then encapsulated with IM to form IM@Cube-DOX and with OMV to form OMV@Cube-OVA. IM@Cube-DOX can be selectively taken up by ID8 cells, leading to effective cell killing, while OMV@Cube-OVA targets and activates DC2.4 cells in vitro. Both IM@Cube-DOX and OMV@Cube-OVA show increased accumulation at ID8 tumors in C57BL/6 mice. Combined IM@Cube-DOX + OMV@Cube-OVA therapy demonstrates better anti-tumor efficacy than non-selective delivery methods such as OMV@(Cube-DOX + Cube-OVA) or IM@(Cube-DOX + Cube-OVA) in ID8-OVA tumor-bearing mice. In conclusion, this study demonstrates a biomimetic delivery strategy that enables selective drug delivery to tumor cells and DCs, thereby enhancing the anti-tumor efficacy of combined chemo- and immunotherapy through the selective delivery strategy.

3.
Redox Biol ; 75: 103244, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38909407

RESUMO

Sphingosine 1-phosphate (S1P), a bioactive lipid molecule, exerts multifaceted effects on cardiovascular functions via S1P receptors, but its effects on cardiac I/R injury are not fully understood. Plasma lipidomics analysis by mass spectrometry revealed that sphingosine lipids, including sphingosine 1-phosphate (S1P), were significantly down-regulated following cardiac I/R injury in mice. The reduced S1P levels were also observed in the plasma of coronary heart disease (CHD) patients after percutaneous coronary intervention (PCI) compared with those without PCI. We found that S1P exerted a cardioprotective effect via endothelial cell (EC)-S1PR1, whereas EC-S1PR2 displayed a detrimental effect on cardiac I/R. Our data showed that EC-specific S1pr2 loss-of-function significantly lessened inflammatory responses and diminished cardiac I/R injury, while EC-specific S1pr2 gain-of-function aggravated cardiac I/R injury. Mechanistically, EC-S1PR2 initiated excessive mitochondrial fission and elevated ROS production via RHO/ROCK1/DRP1 pathway, leading to NLRP3 inflammasome activation and subsequent cell pyroptosis, thereby exacerbating inflammation and I/R injuries. Furthermore, RGD-peptide magnetic nanoparticles packaging S1pr2-siRNA to specifically knockdown S1PR2 in endothelial cells significantly ameliorated cardiac I/R injury. Taken together, our investigations demonstrate that EC-S1PR2 induces excessive mitochondrial fission, which results in NLRP3 inflammasome activation and subsequently triggers cell pyroptosis, ultimately exacerbating inflammatory responses and aggravating heart injuries following I/R.

4.
Small ; : e2403397, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38925625

RESUMO

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.

5.
Small ; : e2403151, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38934338

RESUMO

Developing high electroactivity ruthenium (Ru)-based electrocatalysts for pH-universal hydrogen evolution reaction (HER) is challenging due to the strong bonding strengths of key Ru─H/Ru─OH 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.

6.
Int J Surg ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833337

RESUMO

BACKGROUND: Warfarin is a common oral anticoagulant, and its effects vary widely among individuals. Numerous dose-prediction algorithms have been reported based on cross-sectional data generated via multiple linear regression or machine learning. This study aimed to construct an information fusion perturbation theory and machine learning prediction model of warfarin blood levels based on clinical longitudinal data from cardiac surgery patients. METHODS AND MATERIAL: The data of 246 patients were obtained from electronic medical records. Continuous variables were processed by calculating the distance of the raw data with the moving average (MA ∆vki(sj)), and categorical variables in different attribute groups were processed using Euclidean distance (ED ǁ∆vk(sj)ǁ). Regression and classification analyses were performed on the raw data, MA ∆vki(sj), and ED ǁ∆vk(sj)ǁ. Different machine-learning algorithms were chosen for the STATISTICA and WEKA software. RESULTS: The random forest (RF) algorithm was the best for predicting continuous outputs using the raw data. The correlation coefficients of the RF algorithm were 0.978 and 0.595 for the training and validation sets, respectively, and the mean absolute errors were 0.135 and 0.362 for the training and validation sets, respectively. The proportion of ideal predictions of the RF algorithm was 59.0%. General discriminant analysis (GDA) was the best algorithm for predicting the categorical outputs using the MA ∆vki(sj) data. The GDA algorithm's total true positive rate (TPR) was 95.4% and 95.6% for the training and validation sets, respectively, with MA ∆vki(sj) data. CONCLUSIONS: An information fusion perturbation theory and machine learning model for predicting warfarin blood levels was established. A model based on the RF algorithm could be used to predict the target international normalized ratio (INR), and a model based on the GDA algorithm could be used to predict the probability of being within the target INR range under different clinical scenarios.

7.
BMC Microbiol ; 24(1): 206, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858614

RESUMO

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.


Assuntos
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 , Adulto
8.
Sci Rep ; 14(1): 11274, 2024 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760388

RESUMO

Soil sickness a severe problem in tobacco production, leading to soil-borne diseases and reduce in tobacco yield. This occurs as a result of the interaction between root exudates and rhizosphere microorganisms, which is however, little studied until now. By combining the field investigation and pot experiment, we found the output yield consistently decreased during the first 10 years of continuous cropping in a tobacco field, but increased at the 15th year (15Y). The root exudate and rhizosphere bacterial community was further analyzed to reveal the underlying mechanism of the suppressive soil formation. Root exudate of 15Y tobacco enriched in amino acids and derivatives, while depleted in the typical autotoxins including phenolic acids and alkaloids. This was correlated to the low microbial diversity in 15Y, but also the changes in community composition and topological properties of the co-occurrence network. Especially, the reduced autotoxins were associated with low Actinobacteria abundance, low network complexity and high network modularity, which significantly correlated with the recovered output yield in 15Y. This study revealed the coevolution of rhizosphere microbiota and root exudate as the soil domesticated by continuous cropping of tobacco, and indicated a potential role of the autotoxins and theirs effect on the microbial community in the formation of suppressive soil.


Assuntos
Microbiota , Nicotiana , Raízes de Plantas , Rizosfera , Microbiologia do Solo , Nicotiana/microbiologia , Nicotiana/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Raízes de Plantas/crescimento & desenvolvimento , Exsudatos de Plantas/metabolismo , Solo/química
9.
Emerg Microbes Infect ; 13(1): 2353302, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38753462

RESUMO

Animal models of COVID-19 facilitate the development of vaccines and antivirals against SARS-CoV-2. The efficacy of antivirals or vaccines may differ in different animal models with varied degrees of disease. Here, we introduce a mouse model expressing human angiotensin-converting enzyme 2 (ACE2). In this model, ACE2 with the human cytokeratin 18 promoter was knocked into the Hipp11 locus of C57BL/6J mouse by CRISPR - Cas9 (K18-hACE2 KI). Upon intranasal inoculation with high (3 × 105 PFU) or low (2.5 × 102 PFU) dose of SARS-CoV-2 wildtype (WT), Delta, Omicron BA.1, or Omicron BA.2 variants, all mice showed obvious infection symptoms, including weight loss, high viral loads in the lung, and interstitial pneumonia. 100% lethality was observed in K18-hACE2 KI mice infected by variants with a delay of endpoint for Delta and BA.1, and a significantly attenuated pathogenicity was observed for BA.2. The pneumonia of infected mice was accompanied by the infiltration of neutrophils and pulmonary fibrosis in the lung. Compared with K18-hACE2 Tg mice and HFH4-hACE2 Tg mice, K18-hACE2 KI mice are more susceptible to SARS-CoV-2. In the antivirals test, REGN10933 and Remdesivir had limited antiviral efficacies in K18-hACE2 KI mice upon the challenge of SARS-CoV-2 infections, while Nirmatrelvir, monoclonal antibody 4G4, and mRNA vaccines potently protected the mice from death. Our results suggest that the K18-hACE2 KI mouse model is lethal and stable for SARS-CoV-2 infection, and is practicable and stringent to antiviral development.


Assuntos
Enzima de Conversão de Angiotensina 2 , Antivirais , COVID-19 , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , SARS-CoV-2 , Animais , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/virologia , Camundongos , SARS-CoV-2/genética , SARS-CoV-2/imunologia , SARS-CoV-2/efeitos dos fármacos , Antivirais/farmacologia , Humanos , Pulmão/virologia , Pulmão/patologia , Tratamento Farmacológico da COVID-19 , Queratina-18/genética , Carga Viral , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacologia , Monofosfato de Adenosina/uso terapêutico , Alanina/análogos & derivados , Alanina/farmacologia , Técnicas de Introdução de Genes , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Feminino
10.
Infect Drug Resist ; 17: 1477-1490, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38634066

RESUMO

Purpose: To analyze the time trends in the notification rates of registered tuberculosis (TB) and bacteriologically confirmed TB in Shandong Province. And analyze the changes in TB treatment outcomes during 2005-2021. Patients and Methods: The information of TB patients registered in the Shandong Information Center for Disease Control and Prevention (CDC) was collected during 2005-2021. We calculated the notification rates of registered TB and bacteriologically confirmed TB. Moreover, we calculated the year-to-year change rate of TB in treatment outcomes before and after COVID-19. The time trends were analyzed using the joinpoint regression method and illustrated as the annual percentage change (APC) of notification rates. Results: A total of 236,898 cases of TB were diagnosed during 2005-2021, of which 51.11% were bacteriologically confirmed cases. Since 2008, the notification rates of registered TB have declined. The notification rates of bacteriologically confirmed TB had been declining during 2005-2016, then remained stable after 2016. In subgroup, the notification rates of both registered TB and bacteriologically confirmed TB were higher among men, rural residents, and people aged ≥ 60 years. Compared with clinically confirmed TB, bacteriologically confirmed TB has shown higher rates of poor outcomes since 2008 and higher case fatality rate since 2005. The rate of poor outcomes remained stable during 2008-2019. However, after the COVID-19 outbreak, the rate of poor outcomes and case fatality rate of TB has risen significantly. Conclusion: After unremitting efforts to fight against TB, the notification rates of registered TB and bacteriologically confirmed TB declined in Shandong Province. The rate of poor outcomes remained stable during 2008-2019, then rise significantly after the COVID-19 outbreak. In the context of the long-term existence of COVID-19, further efforts should be made in TB diagnosis and treatment among high-risk population, especially with regard to males, rural residents and older adults.

11.
Front Cell Infect Microbiol ; 14: 1381877, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38572316

RESUMO

Most of vaccinees and COVID-19 convalescents can build effective anti-SARS-CoV-2 humoral immunity, which helps preventing infection and alleviating symptoms. However, breakthrough viral infections caused by emerging SARS-CoV-2 variants, especially Omicron subvariants, still pose a serious threat to global health. By monitoring the viral infections and the sera neutralization ability of a long-tracked cohort, we found out that the immune evasion of emerging Omicron subvariants and the decreasing neutralization led to the mini-wave of SARS-CoV-2 breakthrough infections. Meanwhile, no significant difference had been found in the infectivity of tested SARS-CoV-2 variants, even though the affinity between human angiotensin-converting enzyme 2 (hACE2) and receptor-binding domain (RBDs) of tested variants showed an increasing trend. Notably, the immune imprinting of inactivated COVID-19 vaccine can be relieved by infections of BA.5.2 and XBB.1.5 variants sequentially. Our data reveal the rising reinfection risk of immune evasion variants like Omicron JN.1 in China, suggesting the importance of booster with updated vaccines.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , COVID-19/prevenção & controle , SARS-CoV-2/genética , Infecções Irruptivas , Estudos de Coortes , Evasão da Resposta Imune , Anticorpos Neutralizantes , Anticorpos Antivirais
12.
Medicine (Baltimore) ; 103(12): e37617, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38518003

RESUMO

Multidrug-resistant tuberculosis (MDR-TB) has imposed a significant economic and health burden worldwide, notably in China. Using whole genome sequence, we sought to understand the mutation and transmission of MDR-TB in Shandong. A retrospective study of patients diagnosed with pulmonary tuberculosis in Shandong from 2009 to 2018 was conducted. To explore transmission patterns, we performed whole genome sequencing on MDR-TB isolates, identified genomic clusters, and assessed the drug resistance of TB isolates. Our study analyzed 167 isolates of MDR-TB, finding that 100 were clustered. The predominant lineage among MDR-TB isolates was lineage 2, specifically with a notable 88.6% belonging to lineage 2.2.1. Lineage 4 constituted a smaller proportion, accounting for 4.2% of the isolates. We discovered that Shandong has a significant clustering percentage for MDR-TB, with Jining having the highest percentage among all Shandong cities. The clustering percentages of MDR-TB, pre-extensively drug-resistant tuberculosis, and extensively drug-resistant tuberculosis were 59.9%, 66.0%, and 71.4%, respectively, and the clustering percentages increased with the expansion of the anti-TB spectrum. Isolates from genomic clusters 1 and 3 belonged to lineage 2.2.1 and showed signs of cross-regional transmission. The distribution of rrs A1401G and katG S315T mutations in lineage 2.2.1 and 2.2.2 strains differed significantly (P < .05). MDR-TB isolates with rpoB I480V, embA-12C > T, and rrs A1401G mutations showed a higher likelihood of clustering (P < .05). Our findings indicate a significant problem of local transmission of MDR-TB in Shandong, China. Beijing lineage isolates and some drug-resistant mutations account for the MDR-TB transmission in Shandong.


Assuntos
Tuberculose Extensivamente Resistente a Medicamentos , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Tuberculose Extensivamente Resistente a Medicamentos/epidemiologia , Tuberculose Extensivamente Resistente a Medicamentos/tratamento farmacológico , Farmacorresistência Bacteriana Múltipla/genética , Estudos Retrospectivos , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Mutação , China/epidemiologia , Testes de Sensibilidade Microbiana , Genótipo
13.
BMC Genomics ; 25(1): 249, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448842

RESUMO

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.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Mycobacterium tuberculosis/genética , Sequenciamento Completo do Genoma , Ferro , Mutação , Tuberculose/genética
14.
J Colloid Interface Sci ; 663: 725-734, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38432171

RESUMO

Efficientandinexpensiveoxygenevolutionreaction(OER)catalysts are essential for the electrochemical splitting of water into hydrogen fuel. Herein, we have successfully synthesized NiCoFe(OH)x nanosheets on Ni-Fe foam (NFF) by exploiting the Fenton-like effect of Co2+ and S2O82- to corrode the NFF foam. The as-prepared NiCoFe(OH)x/NFF exhibits the porous structure with the interconnected nanosheets that are firmly bonded to the conductive substrate of NFF, thereby enhancing ions and charge transfer kinetics. The unique structure and composition of NiCoFe(OH)x/NFF result in the low overpotentials of 200 and 262 mV at current densities of 10 and 100 mA cm-2, respectively, as well as a low Tafel slope of 53.25 mV dec-1. In addition, NiCoFe(OH)x/NFF displays low overpotentials of 267 and 294 mV at a high current density of 100 mA cm-2 in simulated and real seawater, respectively. Furthermore, the assembled NiCoFe(OH)x//Pt/C water electrolysis cell has achieved a current density of 10 mA cm-2 at a low voltage of 1.49 V, and displayed the good stability with slight attenuation for 110 h. The high OER performance of NiCoFe(OH)x is attributed to the co-catalytic effect of the three metal ions and the interconnected porous nanosheet structure.

15.
J Colloid Interface Sci ; 665: 345-354, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38531279

RESUMO

The oxygen evolution reaction (OER) is a complex four-electron transfer process that poses a significant challenge to the efficient production of hydrogen through water splitting. However, developing non-noble metal electrocatalyst with excellent OER performance is still a big challenge. Herein, we propose a new strategy for the in-situ growth of two-dimensional amorphous/crystalline thiophene-based Ni-Fe metal-organic frameworks (MOFs) using Ni-Fe foam (NFF) as metal source and current collector, and thiophene-2,5-dicarboxylic acid (TDC) as corrosion agent and ligand. TDC was ionized at high temperature to produce H+ ions that etch NFF to release Ni2+ and Fe2+ ions, which were coordinated with TDC to in situ synthesize two-dimensional Ni-Fe thiophenedicarboxylate coordination polymer (NiFe-TDC) nanobelts on NFF. The unique structure and synergistic effect of Ni and Fe ions of NiFe-TDC0.05 result in the excellent OER performance with an overpotential of 224 and 256 mV at current densities of 10 and 100 mA cm-2, respectively, and it can run stably for 100 h at a current density of 100 mA cm-2, indicating the outstanding stability. Furthermore, NiFe-TDC0.05 remains the excellent OER performance with an extremely low potential of 196 and 271 mV at current densities of 10 and 100 mA cm-2 in seawater with 1 mol L-1 (M) KOH, respectively. The assembled NiFe-TDC0.05 || Pt/C water electrolysis cell achieves a current density of 100 mA cm-2 at a low voltage of 1.78 V. The work provides a new method to prepare two dimensional MOFs for efficient water oxidation.

16.
Environ Sci Pollut Res Int ; 31(18): 27240-27258, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38509309

RESUMO

Growing evidence has found the health protective effects of greenness exposure on tuberculosis (TB) and the impact of ambient air pollutants on TB drug-resistance. However, it remains unclear whether residential greenness is also beneficial to reduce TB drug-resistance, and whether air pollution modify the greenness-TB resistance relationship. We enrolled 5006 newly-diagnosed TB patients from Shandong, China, during 2014 to 2021. Normalized Difference Vegetation Index (NDVI) in 250 m and 500 m buffer around individuals' residential zone was used to assess greenness exposure. All patients were divided by quartiles of NDVI250-m and NDVI500-m (from low to high: Q1, Q2, Q3, Q4) respectively. Six logistic regression models (NDVI, NDVI + PM2.5/PM10/SO2/NO2/O3) were used to estimate the association of NDVI and TB drug-resistance when adjusting different air pollutants or not. All models were adjusted for age, gender, body mass index, complications, smoking, drinking, population density, nighttime light index, road density. Compared with participants in NDVI250-m Q1 and NDVI500-m Q1, other groups had lower rates of MDR-TB, PDR-TB, RFP-resistance, SM-resistance, RFP + SM resistance, INH + RFP + EMB + SM resistance. NDVI500-m reduced the risk of multidrug resistant tuberculosis (MDR-TB) and the adjusted odds ratio (aOR, 95% confidence interval, CI) compared with NDVI500-m Q1 were 0.736 (0.547-0.991) in NDVI + PM10 model, 0.733 (0.544-0.986) in NDVI + PM2.5 model, 0.735(0.546-0.99) in NDVI + SO2 model, 0.736 (0.546-0.991) in NDVI + NO2 model, respectively, P < 0.05. NDVI500-m contributed to a decreased risk of streptomycin (SM)-resistance. The aOR of rifampicin (RFP) + SM resistance were 0.132 (NDVI250-m, Q4 vs Q1, 95% CI: 0.03-0.578), 0.199 (NDVI500-m, Q3 vs. Q1, 95% CI: 0.057-0.688) and 0.264 (NDVI500-m, Q4 vs. Q1, 95% CI: 0.087-0.799). The adjusted ORs (Q2 vs. Q1, 95% CI) of isoniazid (INH) + RFP + ethambutol (EMB) + SM resistance in 500 m buffer were 0.276 (0.119-0.639) in NDVI model, 0.279 (0.11-0.705) in NDVI + PM10 model, 0.281 (0.111-0.713) in NDVI + PM2.5 model, 0.279 (0.11-0.709) in NDVI + SO2 model, 0.296 (0.117-0.754) in NDVI + NO2 model, 0.294 (0.116-0.748) in NDVI + O3 model, respectively. The study showed, for the first time, that residential greenness exposure in 500 m buffer is beneficial for reducing newly-diagnosed DR-TB (including PDR-RB, MDR-TB, MR-TB), and ambient air pollutants may partially mediate this association.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Exposição Ambiental , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , China , Masculino , Feminino , Adulto , Pessoa de Meia-Idade
17.
Glob Chang Biol ; 30(3): e17224, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38459661

RESUMO

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.


Assuntos
Ecossistema , Madeira , Canadá , Florestas , Folhas de Planta , Carbono
19.
Dalton Trans ; 53(11): 5125-5132, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38379520

RESUMO

Here, a cyclometalated Pt(II) clamshell dimer (complex 2) has been synthesized with the primary ligand of dibenzo(f,h)quinoxaline and an ancillary ligand of N,N'-diphenylformamidine. In addition, a mononuclear Pt(II) complex 1a and a binuclear Pt(II) complex 1b were also prepared. Complex 1a was coordinated by one cyclometalated ligand of dibenzo(f,h)quinoxaline, one chloride ion, and one N,N'-diphenylformamidine. Complex 1b was coordinated by one cyclometalated ligand of dibenzo(f,h)quinoxaline, two chloride ions, and two N,N'-diphenylformamidines. All of these three complexes were characterized by nuclear magnetic resonance (NMR) spectroscopy, high-resolution mass spectrometry (HRMS), elemental analyses, and single-crystal X-ray diffraction (XRD). The Pt-Pt distance in complex 2 was 2.8439(2) Å. It also exhibited a near-infrared (near-IR) emission at 887 nm in the pure solid state. On the other hand, complexes 1a and 1b exhibited triplet emission at 589 and 660 nm, respectively, in the pure solid state. Furthermore, in 2 wt% poly(Me methacrylate) (PMMA) films, complex 1a showed a triplet emission at 548 nm (with Φ = 84% and τ = 5.53 µs) and complex 1b showed an emission at 627 nm (with Φ = 79% and τ = 4.07 µs). Due to its great photophysical properties, complex 1b was deposited onto quartz plates for the detection of organic solvent vapors and it showed unique emission quenching for the vapor of tetrahydrofuran.

20.
J Am Chem Soc ; 146(10): 6936-6946, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38414423

RESUMO

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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