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1.
Sci Rep ; 14(1): 2925, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38316874

RESUMO

Focusing on the impact of the digital economy on urban resilience is beneficial to the sustainable development of cities. This paper empirically examines the impact of digital economic development on urban resilience and its mechanisms by measuring urban resilience and the level of urban digital economy with the entropy-weighted TOPSIS method using the data of 252 Chinese cities from 2011 to 2020. The findings show that digital economic development effectively promotes urban resilience at the 1% significance level, and this conclusion remains valid after a series of endogeneity and robustness tests. The channel mechanism suggests that the development of the digital economy can improve urban resilience by optimizing urban distributional effects and promoting the upgrading of urban industrial structures. This paper discusses the nonlinear relationship between the two using the MMQR model and the threshold model. The results show that urban resilience development level is in a higher quartile of cities, and digital economy development has a greater impact on urban resilience improvement. Meanwhile, there are two threshold values for the nonlinear impact of the digital economy on urban resilience, which are 0.026 and 0.082, respectively. Further, the spatial effect between the two is also verified. From the perspective of heterogeneity analysis, the digital economy development of high-class cities, key city clusters, and cities in eastern and western regions has a greater effect on urban resilience. This study can provide ideas and inspiration for countries to enhance urban resilience and promote sustainable urban development through the development of the digital economy.

2.
Transl Pediatr ; 13(1): 164-177, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38323175

RESUMO

Background and Objective: Neuroblastoma (NB) is a common malignant tumor in children, and its treatment remains challenging. Precision medicine, as an individualized treatment strategy, aims to improve efficacy and reduce toxicity by combining unique patient- and tumor-related factors, bringing new hope for NB treatment. In this article, we review the evidence related to precision medicine in NB, with a focus on potential clinically actionable targets and a series of targeted drugs associated with NB. Methods: We conducted an extensive search in PubMed, EMBASE, and Web of Science using key terms and database-specific strategies, filtered for time and language, to ensure a comprehensive collection of literature related to precision medicine in NB. The main search terms consisted of "neuroblastoma", "precision medicine", "pediatrics", and "targeting". The articles included in this study encompass those published from 1985 to the present, without restrictions on the type of articles. Key Content and Findings: ALK inhibitors and MYCN inhibitors have been developed to interfere with tumor cell growth and dissemination, thereby improving treatment outcomes. Additionally, systematic testing to identify relevant driver mutations is crucial and can be used for diagnosis and prognostic assessment through the detection of many associated molecular markers. Furthermore, liquid biopsy, a non-invasive tumor detection method, can complement tissue biopsy and play a role in NB by analyzing circulating tumor DNA and circulating tumor cells to provide genetic information and molecular characteristics of the tumor. Recently, trials conducted by many pediatric oncology groups have shown the urgent need for new approaches to cure relapsed and refractory patients. Conclusions: The purpose of this review is to summarize the latest advances in clinical treatment of NB, to better understand and focus on the development of promising treatment approaches, and to expedite the transition to the precision medicine clinical relevance in NB patients.

3.
PLoS One ; 18(10): e0293474, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37883494

RESUMO

In the context of the rapid development of the global digital economy, it is of great significance to explore the greening transformation of the manufacturing industry from the micro-perspective of enterprise digital development. This paper empirically examines the impact and mechanism of enterprise digital development on the greening transformation of the manufacturing industry using the 2010-2020 data of Chinese A-share listed companies in the manufacturing industry as a sample. The study shows that enterprise digital development can significantly promote the greening transformation of China's manufacturing industry, and this conclusion still holds after a series of robustness tests. Technological innovation and financing constraints are important mediating mechanisms. Further research found that the impact of enterprise digital development on the greening transformation of China's manufacturing industry has a positive nonlinear effect, and its marginal effect shows a weakening trend. Heterogeneity analysis shows that, from the perspective of micro characteristics, digital development is more able to promote the green transformation of state-owned and large enterprises. From a macro-regional perspective, digital development can better promote the green transformation of the manufacturing industry in eastern cities, key city clusters, and high-level cities. The findings of this paper can provide corresponding insights for "revitalizing the manufacturing industry", and also provide decision-making references for countries aiming to make the manufacturing industry bigger and stronger.

4.
Cells ; 12(6)2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36980310

RESUMO

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that results in the loss of motor function in the central nervous system (CNS) and ultimately death. The mechanisms underlying ALS pathogenesis have not yet been fully elucidated, and ALS cannot be treated effectively. Most studies have applied animal or single-gene intervention cell lines as ALS disease models, but they cannot accurately reflect the pathological characteristics of ALS. Induced pluripotent stem cells (iPSCs) can be reprogrammed from somatic cells, possessing the ability to self-renew and differentiate into a variety of cells. iPSCs can be obtained from ALS patients with different genotypes and phenotypes, and the genetic background of the donor cells remains unchanged during reprogramming. iPSCs can differentiate into neurons and glial cells related to ALS. Therefore, iPSCs provide an excellent method to evaluate the impact of diseases on ALS patients. Moreover, patient-derived iPSCs are obtained from their own somatic cells, avoiding ethical concerns and posing only a low risk of immune rejection. The iPSC technology creates new hope for ALS treatment. Here, we review recent studies on iPSCs and their applications in disease modeling, drug screening and cell therapy in ALS, with a particular focus on the potential for ALS treatment.


Assuntos
Esclerose Lateral Amiotrófica , Células-Tronco Pluripotentes Induzidas , Doenças Neurodegenerativas , Animais , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/terapia , Esclerose Lateral Amiotrófica/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Doenças Neurodegenerativas/metabolismo , Neurônios/metabolismo , Terapia Baseada em Transplante de Células e Tecidos
5.
Artigo em Inglês | MEDLINE | ID: mdl-36767097

RESUMO

BACKGROUND: Although several studies have examined the association between chronic kidney disease (CKD) and hyperuricemia (HUA), the direction of the association remains unclear. We aimed to investigate whether there was a bidirectional association between them. METHODS: The present study was conducted in three analyses. Analysis I included 25,433 participants free of HUA at baseline to evaluate the associations between CKD and estimated glomerular filtration rate (eGFR) with incident HUA. Analysis II had 28,422 participants free of CKD at baseline to analyze the relationships between HUA and serum uric acid (sUA) with new-onset CKD. Cox proportional hazards regression models were applied to evaluate the association involved in Analysis I and II. Analysis III included 31,028 participants with complete data and further dissected the bidirectional association between sUA and eGFR using cross-lag models. RESULTS: New-onset HUA and CKD were observed in the first round of the follow-up study among 1597 and 1212 participants, respectively. A significantly higher risk of HUA was observed in individuals with CKD compared to individuals without CKD (HR = 1.58, 95% CI: 1.28-1.95). The adjusted HRs (95% CIs) of HUA were 3.56 (2.50-5.05) for the participants in the group of eGFR less than 60 mL·min-1·1.73 m-2, 1.61 (1.42-1.83) for those in the group of eGFR between 60 and 90 mL·min-1·1.73 m-2, and 1.74 (1.42-2.14) for those in the group of eGFR more than 120 mL·min-1·1.73 m-2, compared with the group of eGFR between 90 and 120 mL·min-1·1.73 m-2. A higher risk of CKD was also observed in individuals with HUA compared to individuals without HUA (HR = 1.28, 95% CI: 1.12-1.47). Compared with the first quintile of sUA, the adjusted HR (95% CI) of CKD was 1.24 (1.01-1.51) for the participants in the fourth quantile. There was a bidirectional relationship between sUA and eGFR, with the path coefficients (ρ1 = -0.024, p < 0.001) from baseline eGFR to follow-up sUA and the path coefficients (ρ2 = -0.015, p = 0.002) from baseline sUA to follow-up eGFR. CONCLUSIONS: The present study indicated that CKD and HUA were closely associated, and there was a bidirectional relationship between sUA and eGFR.


Assuntos
Hiperuricemia , Insuficiência Renal Crônica , Humanos , Hiperuricemia/complicações , Hiperuricemia/epidemiologia , Seguimentos , Estudos Prospectivos , Ácido Úrico , Insuficiência Renal Crônica/complicações , Taxa de Filtração Glomerular , Fatores de Risco
6.
Schizophrenia (Heidelb) ; 9(1): 4, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658140

RESUMO

The public health problems caused by schizophrenia are becoming increasingly prominent and can place a huge economic burden on society. This study takes Gansu Province as an example to analyze the level and changing trend of the economic burden of schizophrenia inpatients in economically underdeveloped areas of China. Using a multi-stage stratified cluster sampling method, 39,054 schizophrenics from 197 medical and health institutions in Gansu Province were selected as the research objects, and their medical expenses and related medical records were obtained from the medical information system. The rank sum test and Spearman rank correlation were used for univariate analysis. Quantile regression and random forest were used to analyze the influencing factors. The results show that the average length of stay of schizophrenics in Gansu Province of China was 52.01 days, and the average hospitalization cost was USD1653.96 from 2014 to 2019. During the six years, the average hospitalization costs per time decreased from USD2136.85 to USD1401.33. The average out-of-pocket costs per time decreased from USD1238.78 to USD267.68. And the average daily hospitalization costs increased from USD38.18 to USD41.25. The main factors influencing hospitalization costs are length of stay, proportion of medications, and schizophrenic subtype. The hospitalization costs per time of schizophrenics in Gansu Province have decreased but remain at a high level compared to some other chronic non-communicable diseases. In the future, attention should be paid to improving the efficiency of medical institutions, enhancing community management, and promoting the transformation of the management model of schizophrenia.

7.
Pediatr Res ; 94(1): 246-251, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36446921

RESUMO

OBJECTIVE: The aim of this study was to evaluate the predictive value of the monocyte-to-high-density lipoprotein ratio (MHR) in Kawasaki disease (KD) complicated with coronary artery lesions (CALs) and to construct a nomogram prediction model. METHODS: The medical records of KD inpatients diagnosed in the Department of Pediatrics of Lanzhou University Second Hospital from May 2015 to September 2021 were retrospectively analyzed. ROC curves were applied to evaluate the predictive value of MHR in KD complicated with CALs, and logistic regression analysis was used to screen independent risk factors. We constructed a nomogram model and performed internal validation. RESULTS: A total of 568 KD patients were enrolled in the study. MHR was significantly higher in KD patients complicated with CALs and was identified as an independent risk factor for CALs (OR: 1.604, 95% CI: 1.292-1.990). The area under the ROC curve for MHR in predicting CALs was 0.661. The C-index of the nomogram model constructed by incorporating MHR was 0.725 (95% CI: 0.682-0.768), and the calibration curve revealed good agreement between the predicted and actual probabilities. CONCLUSIONS: MHR may not be suitable as a single biomarker to predict the occurrence of CALs, but the nomogram model constructed in combination with other independent risk factors had acceptable predictive performance. IMPACT: The inflammatory response plays an important role in the pathogenesis of Kawasaki disease. The monocyte-to-high-density lipoprotein ratio is a novel systemic inflammation marker. The monocyte-to-high-density lipoprotein ratio is an independent risk factor for Kawasaki disease complicated with coronary artery lesions. The nomogram established by incorporating the monocyte-to-high-density lipoprotein ratio has satisfactory predictive performance for coronary artery lesion formation.


Assuntos
Doença da Artéria Coronariana , Síndrome de Linfonodos Mucocutâneos , Humanos , Criança , Monócitos , Lipoproteínas HDL , Síndrome de Linfonodos Mucocutâneos/complicações , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Vasos Coronários , Estudos Retrospectivos
8.
Phytomedicine ; 107: 154426, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36116201

RESUMO

BACKGROUND: Shufeng Jiedu capsule (SFJDC) has been widely used as a conventional Chinese pharmaceutical agent for various upper respiratory infections, including acute lung injury, acute respiratory distress syndrome and allergic rhinitis (AR). However, its mechanism in AR remains unclear. PURPOSE: The present study aimed to decipher the antiallergic inflammatory effect of SFJDC in an AR model with olfactory dysfunction. Specifically, we wanted to explore whether SFJDC can improve the olfactory abnormality in AR mice and reduce the levels of inflammatory factors in the olfactory epithelium (OE) and olfactory bulb (OB). METHODS: To address the above issues, we constructed an AR model using C57BL/6 mice, which were sensitised and challenged with ovalbumin (OVA) by intraperitoneal injection. SFJDC (0.045 or 0.18 g/kg) was delivered by gavage administration 1 h prior to the intraperitoneal injection of OVA. The control mice received saline alone. Then, the animals were assessed according to the presence of nasal symptoms and nasal inflammation, and a buried food test was used to evaluate olfactory function. The levels of proteins involved in the AMPK/mTOR autophagy pathway in the OE and OB were investigated by western blotting and fluorescence staining. RESULTS: After OVA induction of AR and drug administration, we found that SFJDC significantly ameliorated the nasal symptoms and allergic inflammatory reaction of the nasal mucosa superior to cetirizine. A behavioural test indicated that the mice with AR had olfactory dysfunction, and SFJDC can ameliorate this behavior deficiency. Meanwhile, SFJDC clearly reduced the neuroinflammation level in OE tissue. In addition, SFJDC increased p-mTOR and decreased p-AMPK, beclin1, LC3 and cleaved caspase-3 levels in the OE. CONCLUSIONS: In addition to antibacterial and antiviral activities, SFJDC has marked anti-inflammatory effects in AR mice. Its mechanism of action in the nasal cavity involves inhibition of upregulated anti-inflammatory cytokines, modulation of autophagy and apoptosis levels and regulation of autophagy through the AMPK/mTOR pathway in the OE tissue of AR mice. Hence, SFJDC is a promising drug for AR, and clinical trials should further validate the therapeutic impact of SFJDC on AR with olfactory dysfunction.


Assuntos
Antialérgicos , Medicamentos de Ervas Chinesas , Transtornos do Olfato , Rinite Alérgica , Proteínas Quinases Ativadas por AMP , Animais , Antialérgicos/farmacologia , Antialérgicos/uso terapêutico , Antibacterianos/uso terapêutico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antivirais/uso terapêutico , Autofagia , Proteína Beclina-1 , Caspase 3 , Cetirizina/uso terapêutico , Citocinas/metabolismo , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Transtornos do Olfato/tratamento farmacológico , Ovalbumina , Rinite Alérgica/tratamento farmacológico , Serina-Treonina Quinases TOR
9.
Pediatr Blood Cancer ; 69(11): e29949, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36094353

RESUMO

Opsoclonus-myoclonus syndrome (OMS) is a rare neurological disorder. Half of these cases occur in children with neuroblastoma. Neuroblastoma patients with OMS usually have better oncological outcomes than those without OMS even after stratification by tumor stage and age, indicating that factors mediating OMS may also inhibit tumor cell proliferation. Although the mechanisms underlying OMS remain undefined, the cytokines and lymphocytes alterations in the cerebrospinal fluid support the concept that it is a pattern of neuroinflammation due to an autoimmune effect. The presence of lymphoid follicles consisting of follicular dendritic cells, CD20+ B lymphocytes, CD3+ T lymphocytes, and CD68+ macrophages in the tumor microenvironment in OMS-associated neuroblastoma support the autoimmune nature of this disorder. This review focuses on the clinical and genetic features of OMS-associated neuroblastoma, and we update readers on immune features of neuroblastoma with or without OMS to gain insights into antitumor immunity as it relates to tumor biology and prognosis.


Assuntos
Neuroblastoma , Síndrome de Opsoclonia-Mioclonia , Criança , Citocinas , Humanos , Linfócitos , Neuroblastoma/patologia , Prognóstico , Microambiente Tumoral
10.
Nanomaterials (Basel) ; 12(14)2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35889610

RESUMO

Li2O2, as the cathodic discharge product of aprotic Li-O2 batteries, is difficult to electrochemically decompose. Transition-metal oxides (TMOs) have been proven to play a critical role in promoting the formation and decomposition of Li2O2. Herein, a NiO/CNT catalyst was prepared by anchoring a NiO nanosheet on the surface of CNT. When using the NiO/CNT as a cathode catalyst, the Li-O2 battery had a lower overpotential of 1.2 V and could operate 81 cycles with a limited specific capacity of 1000 mA h g-1 at a current density of 100 mA g-1. In comparison, with CNT as a cathodic catalyst, the battery could achieve an overpotential of 1.64 V and a cycling stability of 66 cycles. The introduction of NiO effectively accelerated the generation and decomposition rate of Li2O2, further improving the battery performance. SEM and XRD characterizations confirmed that a Li2O2 film formed during the discharge process and could be fully electrochemical decomposed in the charge process. The internal network and nanoporous structure of the NiO/CNT catalyst could provide more oxygen diffusion channels and accelerate the decomposition rate of Li2O2. These merits led to the Li-O2 battery's better performance.

11.
Exp Neurol ; 348: 113949, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34902357

RESUMO

Depression is one of the most common mental illnesses in modern society. In recent years, several studies show that there are disturbances in lipid metabolism in depressed patients. High-fat diet may lead to anxiety and depression, but the mechanisms involved remain unclear. In our study, we found that 8 weeks of high-fat feeding effectively induced metabolic disorders, including obesity and hyperlipidemia in mice. Interestingly, the mice also showed depressive and anxiety-like behaviors. We further found activated microglia and astrocyte, increased neuroinflammation, decreased autophagy and BDNF levels in mice after high-fat feeding. Besides, high-fat feeding can also inhibit AMPK phosphorylation and induce mTOR phosphorylation. After treating with the mTOR inhibitor rapamycin, autophagy and BDNF levels were elevated. The number of activated microglia and astrocyte, and pro-inflammation levels were reduced. Besides, rapamycin can also reduce the body weight and serum lipid level in high fat feeding mice. Depressive and anxiety-like behaviors were also ameliorated to some extent after rapamycin treatment. In summary, these results suggest that high-fat diet-induced obesity may lead to depressive and anxiety-like behaviors in mice by inhibiting AMPK phosphorylation and promoting mTOR shift to phosphorylation to inhibit autophagy. Therefore, improving lipid metabolism or enhancing autophagy through the AMPK/mTOR pathway could be potential targets for the treatment of obesity depression.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Ansiedade/metabolismo , Depressão/metabolismo , Dieta Hiperlipídica/efeitos adversos , Obesidade/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Ansiedade/psicologia , Autofagia/fisiologia , Peso Corporal/fisiologia , Depressão/psicologia , Metabolismo dos Lipídeos/fisiologia , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/psicologia , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores
12.
Polymers (Basel) ; 13(19)2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34641116

RESUMO

As a class of redox active materials with some preferable properties, including rigid structure, insoluble characters, and large amounts of nitrogen atoms, covalent triazine frameworks (CTFs) have been frequently adopted as electrode materials in Lithium-ion batteries (LIBs). Herein, a triazine-based covalent organic framework employing 3,4-ethylenedioxythiophene (EDOT) as the bridging unit is synthesized by the presence of carbon powder through Stille coupling reaction. The carbon powder was added in an in-situ manner to overcome the low intrinsic conductivity of the polymer, which led to the formation of the polymer@C composite (PTT-O@C, PTT-O is a type of CTFs). The composite material is then employed in LIBs as anode material. The designed polymer shows a narrow band gap of 1.84 eV, proving the effectiveness of the nitrogen-enriched triazine unit in reducing the band gap of the resultant polymers. The CV results showed that the redox potential of the composite (vs. Li/Li+) is around 1.0 V, which makes it suitable to be used as the anode material in lithium-ion batteries. The composite material could exhibit the stable specific capacity of 645 mAh/g at 100 mA/g and 435 mAh/g at 500 mA/g, respectively, much higher than the pure carbon materials, indicating the good reversibility of the material. This work provides some additional information on electrochemical performance of the triazine and EDOT based CTFs, which is helpful for developing a deep understanding of the structure-performance correlations of the CTFs as anode materials.

13.
Plants (Basel) ; 10(6)2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34072565

RESUMO

Chinese chive usually becomes decayed after a short storage time, which was closely observed with the redox imbalance. To cope with this practical problem, in this report, molecular hydrogen (H2) was used to evaluate its influence in maintaining storage quality of Chinese chive, and the changes in antioxidant capacity were also analyzed. Chives were treated with 1%, 2%, or 3% H2, and with air as the control, and then were stored at 4 ± 1 °C. We observed that, compared with other treatment groups, the application of 3% H2 could significantly prolong the shelf life of Chinese chive, which was also confirmed by the obvious mitigation of decreased decay index, the loss ratio of weight, and the reduction in soluble protein content. Meanwhile, the decreasing tendency in total phenolic, flavonoid, and vitamin C contents was obviously impaired or slowed down by H2. Results of antioxidant capacity revealed that the accumulation of reactive oxygen species (ROS) and hydrogen peroxide (H2O2) was differentially alleviated, which positively matched with 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging activity and the improved activities of antioxidant enzymes, including superoxide dismutase (SOD), guaiacol peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX). Above results clearly suggest that postharvest molecular hydrogen application might be a potential useful approach to improve the storage quality of Chinese chive, which is partially achieved through the alleviation of oxidative damage happening during the storage periods. These findings also provide potential theoretical and practical significance for transportation and consumption of perishable vegetables.

14.
Plants (Basel) ; 10(4)2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33808162

RESUMO

This study aimed to obtain the full-length transcriptome of purslane (Portulaca oleracea); assorted plant samples were used for single-molecule real-time (SMRT) sequencing. Based on SMRT, functional annotation of transcripts, transcript factors (TFs) analysis, simple sequence repeat analysis and long non-coding RNAs (LncRNAs) prediction were accomplished. Total 15.33-GB reads were produced; with 9,350,222 subreads and the average length of subreads, 1640 bp was counted. With 99.99% accuracy, after clustering, 132,536 transcripts and 78,559 genes were detected. All unique SMART transcripts were annotated in seven functional databases. 4180 TFs (including transcript regulators) and 7289 LncRNAs were predicted. The results of RNA-seq were confirmed with qRT-PCR analysis. Illumina sequencing of leaves and roots of two purslane genotypes was carried out. Amounts of differential expression genes and related KEGG pathways were found. The expression profiles of related genes in the biosynthesis of unsaturated fatty acids pathway in leaves and roots of two genotypes of purslane were analyzed. Differential expression of genes in this pathway built the foundation of ω-3 fatty acid accumulation in different organs and genotypes of purslane. The aforementioned results provide sequence information and may be a valuable resource for whole-genome sequencing of purslane in the future.

15.
RSC Adv ; 11(11): 5947-5957, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35423155

RESUMO

The exploitation of efficient hydrogen evolution reaction (HER) electrocatalysts has become increasingly urgent and imperative; however, it is also challenging for high-performance sustainable clean energy applications. Herein, novel Co9S8 nanoparticles embedded in a porous N,S-dual doped carbon composite (abbr. Co9S8@NS-C-900) were fabricated by the pyrolysis of a single crystal Co-MOF assisted with thiourea. Due to the synergistic benefit of combining Co9S8 nanoparticles with N,S-dual doped carbon, the composite showed efficient HER electrocatalytic activities and long-term durability in an alkaline solution. It shows a small overpotential of -86.4 mV at a current density of 10.0 mA cm-2, a small Tafel slope of 81.1 mV dec-1, and a large exchange current density (J 0) of 0.40 mA cm-2, which are comparable to those of Pt/C. More importantly, due to the protection of Co9S8 nanoparticles by the N,S-dual doped carbon shell, the Co9S8@NS-C-900 catalyst displays excellent long-term durability. There is almost no decay in HER activities after 1000 potential cycles or it retains 99.5% of the initial current after 48 h.

16.
RSC Adv ; 11(18): 10688-10698, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35423547

RESUMO

The polymers based on thiophene armed triazine and different thiophene derivatives including thiophene (Th), thieno[3,2-b]thiophene (TT), dithieno[3,2-b:2',3'-d]thiophene (DTT) or thieno[2',3':4,5]thieno[3,2-b]thieno[2,3-d]thiophene (TTTT) are synthesized through a Stille coupling reaction. By introducing thiophene derivatives with increasing sizes as the linkage units (from thiophene, DT to DTT, TTTT), the band gaps (E g) of the resultant polymers decrease continuously. Then the composite materials (polymer@C) between polymers and Vulcan XC-72 carbon are prepared by in situ polymerization to test their electrochemical performances in lithium ion batteries. The synthesized composites show distinct morphologies due to the different linkage units of thiophene or fused cyclothiophene derivatives and the cross-linked structure can be found in composites with the longer thiophene derivatives (bridging molecules) like PTT-3@C and PTT-4@C, which are expected to be beneficial to improve the performances of the electrode materials. The specific capacities of the composites are 495 mA h g-1, 671 mA h g-1, 707 mA h g-1, and 772 mA h g-1 for PTT-1@C, PTT-2@C, PTT-3@C and PTT-4@C at a current density of 100 mA g-1, respectively. In particular, benefiting from the enlarged conjugation length and planarity of the linkage units, the conjugated microporous polymers could deliver continuously improved capacities.

17.
RSC Adv ; 11(25): 15044-15053, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35424052

RESUMO

Two conjugated polymer@activated carbon composites were synthesized by the in situ polymerization of two donor-acceptor type polymers including poly[(thiophene-2,5-yl)-((pyrene-4,5,9,10-tetraone)-2,7-yl)] (PTPT) and poly[((2,3-dihydrothieno[3,4-b][1,4]dioxine)-5,7-yl)-((pyrene-4,5,9,10-tetraone)-2,7-yl)] (POTPT) on activated carbon (AC) by one-step cross-coupling reaction catalyzed by an organometallic catalyst. Cyclic voltammetry showed that both polymers exhibited ambipolar properties, low bandgaps, and low electrode potentials, which could be useful for their application as anodes in lithium-ion battery cells (LIBs). For PTPT@AC and POTPT@AC anodes, they showed a high capacity of 253.9 and 370.5 mA h g-1 at 100 mA g-1. Besides, the capacities of pure polymers were calculated to be 693.5 and 1276.5 mA h g-1 for PTPT and POTPT, respectively, at 100 mA g-1. Compared with PTPT, the introduction of the 3,4-ethylenedioxy unit into the side chain of the thiophene unit leads to substantially improved performance of POTPT due to the lowered LUMO energy levels of POTPT and the electron-rich feature of the EDOT unit. It is suggested that the structure-tuning strategy might be an effective method to prepare the new polymer-based anode for next generation LIBs with high performance and high safety.

18.
Cytokine ; 137: 155314, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33002743

RESUMO

Senescent thymic stromal cells (TSCs) producing senescence-associated secretory phenotype (SASP) may play a role at later phases of thymic involution. However, the etiology and mechanisms responsible for TSC senescence remain to be elucidated. In the present study, the effects of oxidative stress on TSCs and role of miRNA-146a-5p in stress-induced premature senescence (SIPS) were identified. D-galactose (D-gal) induced oxidative stress in primary TSCs and a limited cumulative oxidative stress induced premature senescence but not apoptosis of TSCs. miRNA-146a-5p overexpression can mitigate the SIPS by targeting tumor necrosis factor receptor-associated factor 6 (TRAF6) instead of increasing autophagy clearance. Furthermore, exogenous miRNA-146a-5p reversed the upregulation of chemokines including Cxcl5, pro-inflammatory cytokines, and antimicrobial peptides in TSCs with SIPS. In conclusion, the accumulated oxidative stress may be partially responsible for senescence in TSCs and modulation of miRNA-146a-5p may attenuate this process.


Assuntos
Senescência Celular/efeitos dos fármacos , Galactose/farmacologia , MicroRNAs/genética , Estresse Oxidativo/fisiologia , Células Estromais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Células Cultivadas , Senescência Celular/genética , Senescência Celular/fisiologia , Regulação da Expressão Gênica , Camundongos Endogâmicos C57BL , Cultura Primária de Células , Espécies Reativas de Oxigênio/metabolismo , Células Estromais/metabolismo , Fator 6 Associado a Receptor de TNF/genética , Fator 6 Associado a Receptor de TNF/metabolismo , Timo/citologia
19.
Front Microbiol ; 11: 562546, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33240226

RESUMO

Precipitation is predicted to become more intense in Southern China in the context of climate change; however, the responses of microbial communities to variations in soil moisture have not been well documented for karst areas. The climate is typically in a subtropical monsoon category with two different seasons: a dry season (December-May) and a wet season (June-November). Based on a randomized complete block design (RCBD), a water addition experiment (0, +20, +40, and +60% relative to local precipitation) was established in April 2017, with five replicates, in a degraded grass-shrub community. Sampling was performed in May and at the end of August of 2017. Macroelements (C, H, N, P, K, Ca, Mg, and S), microelements (Mn, Fe, Zn, and Cu), and non-essential elements (Na, Al, and Si) were quantified in the soil. The total DNA of the soil samples was analyzed through 16S rRNA amplicon by Illumina Miseq. Subsequent to the addition of water during both the dry and wet seasons, the concentrations of non-metal elements (C, H, N, S, and P, except for Si) in the soil remained relatively stable; however, metal elements (K, Na, Fe, and Mg, along with Si) increased significantly, whereas Zn and Ca decreased. During the dry season, fungal and bacterial communities were significantly distinct from those during the wet season along the PC axis 1 (p < 0.001). Water addition did not alter the compositions of bacterial or fungal communities during the dry season. However, during the wet season, water addition altered the compositions of bacterial rather than fungal community based on principal component analysis. At the phylum level, the relative abundance of Actinobacteria increased with water addition and had a significantly positive correlation with K+ (r 2 = 0.70, p < 0.001) and Na+ (r 2 = 0.36, p < 0.01) contents, whereas that of Acidobacteria, Planctomycetes, and Verrucomicrobia decreased and showed negative correlation with soil K and Na content, and no changes were observed for the fungal phyla. This suggests that the karst bacterial communities can be influenced by the addition of water during the wet season likely linked to changes in soil K and Na contents. These findings implied that increased rainfall might alter the elemental compositions of karst soils, and bacterial communities are likely to be more sensitive to variations in soil moisture in contrast to their fungal counterparts.

20.
J Zhejiang Univ Sci B ; 21(11): 841-855, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33150769

RESUMO

Agriculture is the foundation of social development. Under the pressure of population growth, natural disasters, environmental pollution, climate change, and food safety, the interdisciplinary "new agriculture" is becoming an important trend of modern agriculture. In fact, new agriculture is not only the foundation of great health and new energy sources, but is also the cornerstone of national food security, energy security, and biosafety. Hydrogen agronomy focuses mainly on the mechanism of hydrogen gas (H2) biology effects in agriculture, and provides a theoretical foundation for the practice of hydrogen agriculture, a component of the new agriculture. Previous research on the biological effects of H2 focused chiefly on medicine. The mechanism of selective antioxidant is the main theoretical basis of hydrogen medicine. Subsequent experiments have demonstrated that H2 can regulate the growth and development of plant crops, edible fungus, and livestock, and enhance the tolerance of these agriculturally important organisms against abiotic and biotic stresses. Even more importantly, H2 can regulate the growth and development of crops by changing the soil microbial community composition and structure. Use of H2 can also improve the nutritional value and postharvest quality of agricultural products. Researchers have also shown that the biological functions of molecular hydrogen are mediated by modulating reactive oxygen species (ROS), nitric oxide (NO), and carbon monoxide (CO) signaling cascades in plants and microbes. This review summarizes and clarifies the history of hydrogen agronomy and describes recent progress in the field. We also argue that emerging hydrogen agriculture will be an important direction in the new agriculture. Further, we discuss several scientific problems in hydrogen agronomy, and suggest that the future of hydrogen agronomy depends on contributions by multiple disciplines. Important future research directions of hydrogen agronomy include hydrogen agriculture in special environments, such as islands, reefs, aircraft, and outer space.


Assuntos
Agricultura/métodos , Hidrogênio/química , Monóxido de Carbono/química , Mudança Climática , Produtos Agrícolas/crescimento & desenvolvimento , Inocuidade dos Alimentos , Microbiota , Óxido Nítrico/química , Espécies Reativas de Oxigênio , Solo , Microbiologia do Solo
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