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1.
Neuroimage ; 292: 120620, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38641257

RESUMO

Social pain, a multifaceted emotional response triggered by interpersonal rejection or criticism, profoundly impacts mental well-being and social interactions. While prior research has implicated the right ventrolateral prefrontal cortex (rVLPFC) in mitigating social pain, the precise neural mechanisms and downstream effects on subsequent social attitudes remain elusive. This study employed transcranial magnetic stimulation (TMS) integrated with fMRI recordings during a social pain task to elucidate these aspects. Eighty participants underwent either active TMS targeting the rVLPFC (n = 41) or control stimulation at the vertex (n = 39). Our results revealed that TMS-induced rVLPFC facilitation significantly reduced self-reported social pain, confirming the causal role of the rVLPFC in social pain relief. Functional connectivity analyses demonstrated enhanced interactions between the rVLPFC and the dorsolateral prefrontal cortex, emphasizing the collaborative engagement of prefrontal regions in emotion regulation. Significantly, we observed that negative social feedback led to negative social attitudes, whereas rVLPFC activation countered this detrimental effect, showcasing the potential of the rVLPFC as a protective buffer against adverse social interactions. Moreover, our study uncovered the impact role of the hippocampus in subsequent social attitudes, a relationship particularly pronounced during excitatory TMS over the rVLPFC. These findings offer promising avenues for improving mental health within the intricate dynamics of social interactions. By advancing our comprehension of the neural mechanisms underlying social pain relief, this research introduces novel intervention strategies for individuals grappling with social distress. Empowering individuals to modulate rVLPFC activation may facilitate reshaping social attitudes and successful reintegration into communal life.


Assuntos
Imageamento por Ressonância Magnética , Córtex Pré-Frontal , Estimulação Magnética Transcraniana , Humanos , Estimulação Magnética Transcraniana/métodos , Masculino , Feminino , Adulto Jovem , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiopatologia , Adulto , Atitude , Interação Social , Dor/fisiopatologia , Dor/psicologia , Mapeamento Encefálico/métodos , Córtex Pré-Frontal Dorsolateral/fisiologia , Córtex Pré-Frontal Dorsolateral/diagnóstico por imagem
2.
J Am Chem Soc ; 146(1): 468-475, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38150583

RESUMO

The in-tandem catalyst holds great promise for addressing the limitation of low *CO coverage on Cu-based materials for selective C2H4 generation during CO2 electroreduction. However, the potential mismatch between the CO-formation catalyst and the favorable C-C coupling Cu catalyst represents a bottleneck in these types of electrocatalysts, resulting in low tandem efficiencies. In this study, we propose a robust solution to this problem by introducing a wide-CO generation-potential window nickel single atom catalyst (Ni SAC) supported on a Cu catalyst. The selection of Ni SAC was based on theoretical calculations, and its excellent performance was further confirmed by using in situ IR spectroscopy. The facilitated carbon dimerization in our tandem catalyst led to a ∼370 mA/cm2 partial current density of C2H4, corresponding to a faradic efficiency of ∼62%. This performance remained stable and consistent for at least ∼14 h at a high current density of 500 mA/cm2 in a flow-cell reactor, outperforming most tandem catalysts reported so far.

3.
Nephrology (Carlton) ; 29(6): 344-353, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38438117

RESUMO

AIM: Patients with chronic kidney disease (CKD) are more susceptible to endothelial dysfunction and cardiovascular disease (CV). Remote ischemic preconditioning (rIPC) has been proven efficient in improving endothelial function and lowering the risk of CV. However, the safety and effect of rIPC on endothelial function in patients with CKD have not been effectively assessed. METHODS: 45 patients with CKD (average estimated glomerular filtration rate: 48.4 mL/min/1.73 m2) were randomly allocated to either 7-day daily upper-arm rIPC (4 × 5 min 200 mmHg, interspaced by 5-min reperfusion) or control (4 × 5 min 60 mmHg, interspaced by 5-min reperfusion). Vascular endothelial function was assessed by natural log-transformed reactive hyperemia index (LnRHI) before and after a 7-day intervention. Arterial elasticity was assessed by augmentation index (AI). RESULTS: The results showed that LnRHI could be improved by rIPC treatment (Pre = 0.57 ± 0.04 vs. Post = 0.67 ± 0.04, p = .001) with no changes relative to control (Pre = 0.68 ± 0.06 vs. Post = 0.64 ± 0.05, p = .470). Compared with the control group, the improvement of LnRHI was greater after rIPC treatment (rIPC vs. Control: 0.10 ± 0.03 vs. -0.04 ± 0.06, between-group mean difference, -0.15 [95% CI, -0.27 to -0.02], p = .027), while there was no significant difference in the change of AI@75 bpm (p = .312) between the two groups. CONCLUSION: RIPC is safe and well tolerated in patients with CKD. This pilot study suggests that rIPC seems to have the potential therapeutic effect to improve endothelial function. Of note, further larger trials are still warranted to confirm the efficacy of rIPC in improving endothelial function in CKD patients.


Assuntos
Endotélio Vascular , Precondicionamento Isquêmico , Insuficiência Renal Crônica , Humanos , Masculino , Projetos Piloto , Precondicionamento Isquêmico/métodos , Precondicionamento Isquêmico/efeitos adversos , Insuficiência Renal Crônica/terapia , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/diagnóstico , Feminino , Endotélio Vascular/fisiopatologia , Pessoa de Meia-Idade , Idoso , Resultado do Tratamento , Rigidez Vascular , Fatores de Tempo , Extremidade Superior/irrigação sanguínea , Taxa de Filtração Glomerular
4.
BMC Nephrol ; 25(1): 118, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38556867

RESUMO

BACKGROUND: Nonmalignant pleural effusion (NMPE) is common and remains a definite health care problem. Pleural effusion was supposed to be a risk factor for acute kidney injury (AKI). Incidence of AKI in NMPE patients and whether there is correlation between the size of effusions and AKI is unknown. OBJECTIVE: To assess the incidence of AKI in NMPE inpatients and its association with effusion size. STUDY DESIGN AND METHOD: We conducted a retrospective cohort study of inpatients admitted to the Chinese PLA General Hospital with pleural effusion from 2018-2021. All patients with pleural effusions confirmed by chest radiography (CT or X-ray) were included, excluding patients with diagnosis of malignancy, chronic dialysis, end-stage renal disease (ESRD), community-acquired AKI, hospital-acquired AKI before chest radiography, and fewer than two serum creatinine tests during hospitalization. Multivariate logistic regression and LASSO logistic regression models were used to identify risk factors associated with AKI. Subgroup analyses and interaction tests for effusion volume were performed adjusted for the variables selected by LASSO. Causal mediation analysis was used to estimate the mediating effect of heart failure, pneumonia, and eGFR < 60 ml/min/1.73m2 on AKI through effusion volume. RESULTS: NMPE was present in 7.8% of internal medicine inpatients. Of the 3047 patients included, 360 (11.8%) developed AKI during hospitalization. After adjustment by covariates selected by LASSO, moderate and large effusions increased the risk of AKI compared with small effusions (moderate: OR 1.47, 95%CI 1.11-1.94 p = 0.006; large: OR 1.86, 95%CI 1.05-3.20 p = 0.028). No significant modification effect was observed among age, gender, diabetes, bilateral effusions, and eGFR. Volume of effusions mediated 6.8% (p = 0.005), 4.0% (p = 0.046) and 4.6% (p < 0.001) of the effect of heart failure, pneumonia and low eGFR on the development of AKI respectively. CONCLUSION: The incidence of AKI is high among NMPE patients. Moderate and large effusion volume is independently associated with AKI compared to small size. The effusion size acts as a mediator in heart failure, pneumonia, and eGFR.


Assuntos
Injúria Renal Aguda , Insuficiência Cardíaca , Derrame Pleural , Pneumonia , Humanos , Estudos Retrospectivos , Derrame Pleural/diagnóstico por imagem , Derrame Pleural/epidemiologia , Pneumonia/epidemiologia , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/complicações , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/complicações
5.
Angew Chem Int Ed Engl ; 63(28): e202401333, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38670936

RESUMO

The poor electrocatalytic stability and rapid deactivation of metal electrocatalysts are always present in the electrocatalytic conversion of carbon dioxide (CO2) due to the harsh reduction condition. Herein, we demonstrate the controllable dispersion of ultrafine bismuth nanoparticles among the hollow carbon shell (Bi@C-700-4) simply by a thermal-driven diffusion process. The confinement effect of nitrogen-doped carbon matrix is able to low the surface energy of bismuth nanoparticles against the easy aggregation commonly observed for the thermal treatment. On the basis of the synergistic effect and confinement effect between bismuth nanoparticles and carbon matrix, the highly dispersed active sites render the obviously improved electrocatalytic activity and stability for CO2 reduction into formate. The in situ experimental observations on the reduction process and theoretical calculations reveal that the incorporation of bismuth nanoparticles with nitrogen-doped carbon matrix would promote the activation of CO2 and the easy formation of key intermediate (*OCHO), thus leading the enhanced electrocatalytic activity, with a Faradaic Efficiency (FE) of formate about 94.8 % and the long-time stability. Furthermore, the coupling of an anode for 5-hydroxymethylfurfural oxidation reaction (HMFOR) in solar-driven system renders the high 2,5-furandicarboxylic acid (FDCA) yield of 81.2 %, presenting the impressive solar-to-fuel conversion.

6.
Angew Chem Int Ed Engl ; 63(28): e202405438, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38682249

RESUMO

The alkaline oxygen evolution reaction (OER) is a promising avenue for producing clean fuels and storing intermittent energy. However, challenges such as excessive OH- consumption and strong adsorption of oxygen-containing intermediates hinder the development of alkaline OER. In this study, we propose a cooperative strategy by leveraging both nano-scale and atomically local electric fields for alkaline OER, demonstrated through the synthesis of Mn single atom doped CoP nanoneedles (Mn SA-CoP NNs). Finite element method simulations and density functional theory calculations predict that the nano-scale local electric field enriches OH- around the catalyst surface, while the atomically local electric field improves *O desorption. Experimental validation using in situ attenuated total reflection infrared and Raman spectroscopy confirms the effectiveness of the nano-scale and atomically electric fields. Mn SA-CoP NNs exhibit an ultra-low overpotential of 189 mV at 10 mA cm-2 and stable operation over 100 hours at ~100 mA cm-2 during alkaline OER. This innovative strategy provides new insights for enhancing catalyst performance in energy conversion reactions.

7.
J Am Chem Soc ; 145(37): 20624-20633, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37695570

RESUMO

With significant advances in metal-organic framework (MOF) nanostructure preparation, however, the facile synthesis of large-scale MOF films with precise control of the interface structure and surface chemistry is still challenging to achieve with satisfactory performance. Herein, we introduce a universal strategy bridging metal corrosion chemistry and bionic mineralization to synthesize 16 MOF films on 7 metal supports under ambient conditions. The robustness to explore unlimited libraries of MOF films (e.g., carboxylate-, N-heterocycle-, phenolic-, and phosphonate-MOFs) on supports is evoked by independently regulating the metal redox behavior, electrolyte properties, and organic ligands along with hydrogen evolution or oxygen reduction, which offers the basic guidelines for regulating the microstructure and composition of MOFs on the Pourbaix diagram. In conjunction with multiple manufacturing methods, we demonstrated proof of concept for "printing" a large variety of MOF patterns from micrometer to meter scales. Furthermore, a large-area electrolyzer (64 cm2) devised enables 5-hydroxymethylfurfural oxidation to achieve a record-breaking current of 3.0 A at 1.63 V with 2,5-furandicarboxylic acid production, leading to the simultaneous production of H2 gas and valuable feedstocks. The improved electrocatalytic activity for significantly boosting the 5-hydroxymethylfurfural oxidation exemplifies one of the functional MOF films for given applications beyond biomass upgrading.

8.
Anal Chem ; 95(17): 6989-6995, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37083370

RESUMO

Among the various types of post-translational modifications (PTMs), methylation is the simple functionalized one that regulates the functions of proteins and affects interactions of protein-protein and protein-DNA/RNA, which will further influence diverse cellular processes. The methylation modification has only a slight effect on the size and hydrophobicity of proteins or peptides, and it cannot change their net charges at all, so the methods for recognizing methylated protein are still limited. Here, we designed a recognition receptor consisting of a α-hemolysin (α-HL) nanopore and polyamine decorated γ-cyclodextrin (am8γ-CD) to differentiate the methylation of peptide derived from a heterogeneous nuclear ribonucleoprotein at the single molecule level. The results indicate that the modification of a methyl group enhances the interaction between the peptide and the recognition receptor. The results of molecular simulations were consistent with the experiments; the methylated peptide interacts with the receptor strongly due to the more formation of hydrogen bonds. This proposed strategy also can be used to detect PTM in real biological samples and possesses the advantages of low-cost and high sensitivity and is label-free. Furthermore, the success in the construction of this recognition receptor will greatly facilitate the investigation of pathogenesis related to methylated arginine.


Assuntos
Arginina , Proteínas , Arginina/química , Metilação , Proteínas/metabolismo , RNA/metabolismo , Peptídeos/química , Processamento de Proteína Pós-Traducional
9.
Hum Brain Mapp ; 44(13): 4710-4721, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37376719

RESUMO

The right ventrolateral prefrontal cortex (rVLPFC) is highly engaged in emotion regulation of social pain. However, there is still lack of both inhibition and excitement evidence to prove the causal relationship between this brain region and voluntary emotion regulation. This study used high-frequency (10 Hz) and low-frequency (1 Hz) repetitive transcranial magnetic stimulation (rTMS) to separately activate or inhibit the rVLPFC in two groups of participants. We recorded participants' emotion ratings as well as their social attitude and prosocial behaviors following emotion regulation. Also, we used eye tracker to record the changes of pupil diameter to measure emotional feelings objectively. A total of 108 healthy participants were randomly assigned to the activated, inhibitory or sham rTMS groups. They were required to accomplish three sequential tasks: the emotion regulation (cognitive reappraisal) task, the favorability rating task, and the donation task. Results show that the rVLPFC-inhibitory group reported more negative emotions and showed larger pupil diameter while the rVLPFC-activated group showed less negative emotions and reduced pupil diameter during emotion regulation (both compared with the sham rTMS group). In addition, the activated group gave more positive social evaluation to peers and donated more money to a public welfare activity than the rVLPFC-inhibitory group, among which the change of social attitude was mediated by regulated emotion. Taken together, these findings reveal that the rVLPFC plays a causal role in voluntary emotion regulation of social pain and can be a potential brain target in treating deficits of emotion regulation in psychiatric disorders.


Assuntos
Regulação Emocional , Humanos , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Emoções/fisiologia , Estimulação Magnética Transcraniana , Córtex Cerebral
10.
Behav Brain Funct ; 19(1): 15, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37726856

RESUMO

Emotion regulation (ER) refers to the process through which people influence the occurrence, experience, and expression of emotions. It can be established in an explicit (voluntary) or implicit (automatic) way, both of which are essential for mental and physical well-being. Recent evidence has highlighted the potential of transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) targeting the prefrontal cortex (PFC) to modulate ER. However, previous studies have only evaluated the effects of TMS and tDCS on explicit ER, leaving implicit ER relatively unexplored. In this review and meta-analysis, we systematically evaluated the effects of TMS and tDCS over the PFC on the two forms of ER, using both subjective and physiological response as outcome indicators. Twenty-seven studies were included in our study. Both subjective (Hedges' g = - 0.20) and physiological (Hedges' g = - 0.65) results indicated a significant effect of TMS and tDCS targeting PFC on down-regulation of explicit ER, but not implicit ER (Hedges' g = - 0.04). Moreover, moderation analysis indicated that the effect of TMS and tDCS on the down-regulating of subjective experience was moderated by several factors, including stimulation method, target area, target hemisphere, and stimulation timing. Specifically, our results showed that applying TMS or targeting the right PFC, particularly the right ventrolateral prefrontal cortex, or using offline TMS and tDCS produced a larger stimulation effect on ER. In summary, these findings suggest that TMS and tDCS has a positive effect on explicit, but not implicit ER. The distinct TMS and tDCS effect on the two forms of ER help deepen our understanding of TMS and tDCS use and provide valuable insights for the development of tailored TMS and tDCS protocols for explicit and implicit regulation.


Assuntos
Regulação Emocional , Estimulação Transcraniana por Corrente Contínua , Humanos , Estimulação Magnética Transcraniana , Emoções , Córtex Cerebral
11.
Semin Dial ; 36(2): 117-130, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35352408

RESUMO

BACKGROUND: The implementation of automated peritoneal dialysis (APD) has considerably increased in many countries. We conducted a bibliometric analysis to evaluate the accumulating studies on APD in the last two decades quantitatively and qualitatively. METHODS: Publications regarding APD research between 2000 and 2020 were retrieved from the Web of Science Core Collection database by using the index term "automated peritoneal dialysis." CiteSpace, VOSviewer, and an online platform were employed to analyze the number of publications and the collaboration relationships between countries, institutions, authors, and co-cited journals. Cluster analysis and burst keywords detection were performed on co-cited references and keywords, respectively. RESULTS: We obtained a record of 545 publications related to APD in total. The United States was the country that contributes most, and Baxter Healthcare Corporation was the leading institution. Peritoneal Dialysis International was the most active journals in this field. Claudio Ranco was the most productive author, and Simon J Davies ranked the first in the cited authors. Co-cited reference cluster analysis and high frequency keywords showed that survival, ultrafiltration and peritonitis are continuous hot topics. While remote monitoring (RM) and telemedicine may be APD research frontiers according to burst keywords detection. CONCLUSION: This bibliometric study provides comprehensive overview on the publications of APD over the past two decades. These findings help to identify the hotspots and explore new directions for future research. RM has become an emerging trend in APD field.


Assuntos
Diálise Peritoneal , Peritonite , Humanos , Diálise Renal , Bibliometria , Bases de Dados Factuais
12.
Semin Dial ; 36(3): 214-220, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36450343

RESUMO

INTRODUCTION: Along with the peritoneal dialysis (PD)-favored policy in China and the implementation of more comprehensive PD management, PD has evolved in Chinese mainland over the last decade. Despite the existence of national registries and several provincial epidemiological descriptive studies, there was almost no national research on the changing trajectory in PD population. A comparison study, based on two national surveys that were 10 years apart, was conducted to reveal the evolvement of PD care in Chinese mainland. METHODS: Two national surveys have been done respectively in 2010 and 2020 to capture the epidemiological status, application of different modalities, management of perioperative infection, and long-term complications among PD patients. RESULTS: In the study with 730 participating hospitals (n = 14,912 PD patients) in 2010 and 746 hospitals (n = 101,537) in 2020, prevalent PD patients have increased in the past 10 years with increased numbers of PD patients in both secondary (average 5 ± 16 vs. 43 ± 41, p < 0.01) and tertiary hospitals (32 ± 53 vs. 153 ± 215, p < 0.01). Automated PD has been accessible in 0.4% of all hospitals, only in tertiary centers in 2010 and its application increased to 51% in 2020. PD centers have become more engaged in PD catheter placement, treated properly for the PD-related infection, and carried out the follow-up in compliance with the national protocols. CONCLUSIONS: Our study indicates that over the past decade, the prevalent PD population has quickly expanded with increased APD availability in Chinese mainland. The management of PD patients has become better conforming to the guidelines and long-term follow-up of patients have remained stable. Further studies are warranted to evaluate whether the rapidly changing paradigm of PD could translate into the socio-economic benefits in the society.


Assuntos
Diálise Peritoneal , Peritonite , Humanos , População do Leste Asiático , Diálise Renal , Diálise Peritoneal/métodos , Inquéritos e Questionários , Cateterismo
13.
Ren Fail ; 45(2): 2284229, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38031397

RESUMO

INTRODUCTION: Peritoneal dialysis (PD)-related peritonitis is a serious complication of PD. Improving the diagnostic rate of peritonitis pathogens may substantially benefit peritonitis patients. METHODS: The study was conducted in the People's Liberation Army (PLA) General Hospital from 1 June 2021 to 31 May 2022. Information about peritonitis, culture and metagenomic next-generation sequencing (mNGS) results and so on were collected. Patients were divided into antibiotic-use and antibiotic-free groups. The culture and mNGS results were compared using the paired χ2 test. RESULTS: Data from 26 patients with peritonitis were collected. 50% of the patients had used antibiotics before samples were obtained (antibiotic-use group). The positivity rate using culture was 92.3% (12 cases) in the antibiotic-free group and 38.5% (5 cases) in the antibiotic-use group (p = 0.011). However, the positivity rate using mNGS was 92.3% (12 cases) regardless of whether antibiotics were used (p = 1.000). After revising the mNGS results, the positivity rate was 84.6% (11 cases) in both groups (p = 1.000). A significant difference between culture and mNGS results of all groups was observed (p = 0.039). The difference no matter between culture and mNGS (p = 0.016) or between culture and modified mNGS (p = 0.031) of the antibiotic-use group was observed. CONCLUSION: For patients with PD-related peritonitis who previously received antibiotics, mNGS is suggested. For other patients, mNGS testing can be performed, but the results should be interpreted with caution. Much more research should be done to identify a powerful and ideal tool to detect pathogens underlying PD-related peritonitis.


Assuntos
Diálise Peritoneal , Peritonite , Humanos , Projetos Piloto , Sequenciamento de Nucleotídeos em Larga Escala , Antibacterianos/uso terapêutico , Diálise Peritoneal/efeitos adversos , Peritonite/diagnóstico , Peritonite/etiologia , Sensibilidade e Especificidade
14.
Nano Lett ; 22(15): 6298-6305, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35881079

RESUMO

The electrocatalytic generation of valuable fuels and chemicals from carbon dioxide (CO2) and others with the assistance of clean solar energy is a highly promising way to realize the carbon-neutral cycle, which invokes the systematic development of advanced electrocatalysts for efficient and selective redox reactions of feedstocks. Herein, we demonstrate the interface modification of cuprous oxide with polyvinylpyrrolidone (PVP) to improve the electrocatalytic efficiency for the synchronous formate generation. Density functional theory calculations reveal that the interfacial properties can be effectively regulated by the PVP functionalization for the favorable formation of intermediates to improve the selectivity of formate generation. Importantly, the advanced electrocatalyts enable an efficient coupling of CO2 reduction with methanol oxidation in an electrochemical cell powered with a solar cell. The work provides a predictive link between the electrocatalytic redox reactions by applying the interfacial regulation strategies of electrocatalysts.


Assuntos
Dióxido de Carbono , Energia Solar , Dióxido de Carbono/química , Formiatos/química , Oxirredução
15.
Environ Monit Assess ; 195(12): 1488, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37975891

RESUMO

This study aimed to investigate the distribution and migration characteristics of lead (Pb) and zinc (Zn) in paddy soils in Hunan Province, China. A total of 343 soil samples from 63 profiles were collected from typical regions. The concentration, spatial distribution, and migration behaviors of Pb and Zn in the paddy soils were examined. The results showed that (1) the concentration ranges of Pb and Zn in the surface layer were 17.62-114.07 mg/kg and 44.98-146.84 mg/kg, respectively. (2) The content was higher in the middle and lower reaches of the Xiangjiang River basin horizontally and exhibited shallow enrichment characteristics vertically. (3) Pb migration was weaker than Zn migration, and the parent material had the most significant influence on Pb and Zn content in the bottom soil layer. The research results will clarify the characteristics of Pb and Zn contents in paddy soils in Hunan Province, further understand the horizontal distribution and vertical migration and transformation characteristics of Pb and Zn contents in paddy soils, and provide basic data for scientific rice cultivation and safe food production.


Assuntos
Metais Pesados , Oryza , Poluentes do Solo , Zinco/análise , Solo , Chumbo , Poluentes do Solo/análise , Monitoramento Ambiental , China , Metais Pesados/análise
16.
J Am Chem Soc ; 144(47): 21683-21691, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36394983

RESUMO

Zinc-iodine batteries are promising energy storage devices with the unique features of aqueous electrolytes and safer zinc. However, their performances are still limited by the polyiodide shuttle and the unclear redox mechanism of iodine species. Herein, a single iron atom was embedded in porous carbon with the atomic bridging structure of metal-nitrogen-carbon to not only enhance the confinement effect but also invoke the electrocatalytic redox conversion of iodine, thereby enabling the large capacity and good cycling stability of the zinc-iodine battery. In addition to the physical trapping effect of porous carbon with good electronic conductivity, the in situ experimental characterization and theoretical calculation reveal that the metal-nitrogen-carbon bridging structure modulates the electronic properties of carbon and adjusts the intrinsic activity for the reversible conversion of iodine via the thermodynamically favorable pathway. This work demonstrates that the physicochemical confinement effect can be invoked by the rational anchoring of a single metal atom with nitrogen in a porous carbon matrix to enhance the electrocatalytic redox conversion of iodine, which is crucial to fabricating high-performing zinc-iodine batteries and beyond by applying the fundamental principles.

17.
Angew Chem Int Ed Engl ; 61(6): e202113918, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34907631

RESUMO

To meet strategic applications, electrochemical reduction of CO2 into value-added chemical molecules would be improved by the rational design of advanced electrocatalysts with atomically dispersed active sites. Herein an electrospun-pyrolysis cooperative strategy is presented to not only modulate the porous structure of the carbon support for favorable charge and mass transfer, but also adjust the bridging structure of atomically dispersed metal species. Typically, the experimental results and theoretical calculations revealed that the unique chemical structure of binuclear nickel bridging with nitrogen and carbon atoms (namely Ni2 -N4 -C2 ) tunes the electronic nature of the d-states for the optimal adsorption of carbon dioxide and intermediates, thus inducing the substantial enhancement of CO2 reduction via the thermodynamically more favorable pathway. The identification of such a structure demonstrates the large space to modulate the atomic bridging status for optimizing electrocatalysis.

18.
Nephrology (Carlton) ; 26(1): 54-61, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32749777

RESUMO

BACKGROUND: Endothelial dysfunction is common in patients undergoing hemodialysis (HD). However, little is known about the relationship between endothelial dysfunction and coenzyme Q10 (CoQ10) levels in HD patients. METHODS: Eligible HD patients were enrolled in this study according to prespecified inclusion and exclusion criteria. Endothelial function was assessed by brachial artery flow-mediated dilation (FMD). Plasma CoQ10, serum malondialdehyde (MDA) and 8-hydroxydeoxyguanosine (8-OHdG) levels were measured. The potential confounders identified by univariate analyses (P < 0.15) were selected in a stepwise multiple regression model. RESULTS: In total, 111 HD patients were enrolled in this study. The mean CoQ10 level was 633.53 ± 168.66 ng/mL, and endothelial dysfunction was prevalent (91.0%) using a cut-off value of 10% FMD. A significant correlation was observed between FMD and plasma CoQ10 level (r = 0.727, P < 0.001). After adjusting for potential parameters, a stepwise multivariate linear regression analysis revealed that CoQ10 level was an independent predictor of FMD (ß = 0.018, P < 0.001). When CoQ10 was dichotomized using the median value (639.74 ng/mL), the conclusion remained unchanged (ß = 0.584, P < 0.001). Pearson's correlation analyses revealed that plasma CoQ10 level was negatively correlated with MDA (r = -0.48, P < 0.001) and 8-OHdG (r = -0.43, P < 0.001) levels. CONCLUSION: Our data demonstrate that impaired brachial artery FMD was common in HD patients. CoQ10 level was independently associated with FMD, and oxidative stress may constitute a link between CoQ10 level and endothelial dysfunction in these patients.


Assuntos
Artéria Braquial/fisiopatologia , Endotélio Vascular , Falência Renal Crônica , Diálise Renal , Ubiquinona/análogos & derivados , 8-Hidroxi-2'-Desoxiguanosina/sangue , Correlação de Dados , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/fisiopatologia , Falência Renal Crônica/terapia , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Estresse Oxidativo , Diálise Renal/efeitos adversos , Diálise Renal/métodos , Ubiquinona/sangue , Vasodilatação/fisiologia
19.
Molecules ; 26(20)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34684797

RESUMO

Rosa roxburghii tratt (RRT), widely distributed in the southwest of China, is favored by consumers for its good taste and healthy functions. In this study, thirty-seven compounds of Rosa roxburghii Tratt (RRT) were identified and quantified by gas chromatography-olfactometry (G-O) and gas chromatography-mass spectrometry (GC-MS) analysis. Furthermore, ethyl 2-methylpropanoate, ethyl butanoate, ethyl 2-methylbutyrate, and ethyl hexanoate were present with much higher odor activity values (OAVs) than other compounds. The key notes were confirmed by omission tests. Possible interaction among key notes was investigated through odor intensity determination and sensory analysis. It showed fruity and woody notes had synergistic effects. Full factorial design was used to evaluate the notes contribution to the whole odor. One important finding is the major effect of order interactions, fruity note (X1) and woody note (X4) especially, emphasizing the existence of complex interactions occurring between odor notes. The interaction X1X4 was further investigated. The woody note has a positive effect when the fruity note is also in the mixture but tends to show a negative effect otherwise.


Assuntos
Odorantes/análise , Rosa/química , Compostos Orgânicos Voláteis/química , China , Medicamentos de Ervas Chinesas/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Olfatometria , Microextração em Fase Sólida
20.
Fish Shellfish Immunol ; 107(Pt A): 26-35, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33011434

RESUMO

Activating transcription factor 2 (ATF2), a member of the bZIP transcription factor family, is involved in multiple physiological and developmental processes, yet its role in the innate immunity remains unclear. In this study, two isoforms (named as MnATF2a and MnATF2b) of ATF2 gene were identified in Macrobrachium nipponense and were produced by exon skipping. The full length of MnATF2a is 2328 bp with an open reading frame of 2079 bp that encode 692 amino acids. MnATF2a has 237 bp nucleotides more than MnATF2b and the extra 237 bp is a complete exon. MnATF2a and MnATF2b proteins contain the same conserved and typical bZIP domain at the C-terminus. MnATF2a has 79 amino acids more than MnATF2b. MnATF2a and MnATF2b are widely distributed in a variety of immune tissues. After Vibrio parahaemolyticus and Staphylococcus aureus infection, the expression levels of MnATF2a and MnATF2b were significant up-regulated in the gills and stomach at 12 h. RNA interference analysis showed that knockdown of the total MnATF2 gene significantly inhibits the transcription of tumor necrosis factor (TNF) and promotes the expression of crustins (including Cru3, Cru4, and Cru7). Further study showed that knockdown of MnTNF evidently increase the expression of Cru3, Cru4, and Cru7. Our research indicates that ATF2 negatively regulate the expression of AMPs by regulating the transcription of TNF in M. nipponense. This study provides valuable information about the function of ATF2 family in the innate immunity in crustacean.


Assuntos
Fator 2 Ativador da Transcrição/genética , Fator 2 Ativador da Transcrição/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Penaeidae/genética , Penaeidae/imunologia , Fator 2 Ativador da Transcrição/química , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Sequência de Bases , Perfilação da Expressão Gênica , Filogenia , Isoformas de Proteínas , Distribuição Aleatória , Alinhamento de Sequência , Staphylococcus aureus/fisiologia , Vibrio parahaemolyticus/fisiologia
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