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1.
Front Nutr ; 11: 1418393, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39021606

RESUMEN

Background: The consumption of sugar-sweetened beverages (SSBs) has become a major public health problem globally. However, no studies have specifically examined the relationship between SSB intake and chronic low back pain (CLBP). Therefore, the present study aimed to investigate the relationship between SSB intake and the risk of CLBP. Methods: This cross-sectional study enrolled participants aged 20 to 69 from the National Health and Nutrition Examination Survey. CLBP was defined as persistent LBP for a consecutive three-month period. Furthermore, SSB intake was assessed and calculated based on dietary recall interviews. Moreover, survey-weighted logistic regression models were employed to evaluate the association between SSB intake and the risk of CLBP, while the restricted cubic spline (RCS) analysis was used to determine whether there were nonlinear associations between SSB intake and CLBP risk. In addition, subgroup analysis was performed using stratification and interaction analysis for all covariates. Results: A total of 4,146 participants (mean age: 43.405 years) were enrolled in the final analysis. The results of survey-weighted logistic regression models showed that SSB consumption was significantly associated with an increased risk of CLBP among individuals aged 20 to 69 years. Moreover, the results of subgroup analysis and interaction analysis demonstrated that the association between SSB intake and the risk of CLBP was modified by smoking status and hypertension. Specifically, the SSB intake-associated CLBP risk was more pronounced among current smokers or individuals with hypertension. Conclusion: Reduction of SSB consumption might contribute to the prevention of CLBP for individuals aged 20 to 69 years. Moreover, current smokers or individuals with hypertension should be more vigilant about the SSB intake-associated CLBP risk. Nevertheless, caution should be exercised when interpreting the results of this study, as further research is necessary to explore the association between SSB consumption and CLBP, given the limitations of the current study.

2.
Water Sci Technol ; 90(1): 225-237, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39007316

RESUMEN

To solve the problem of low removal rate and poor N2 selectivity in direct electrochemical ammonia oxidation (EAO), commercial Ni foam and Cu foam were used as anode and cathode of the EAO system, respectively. The coupling effect between the cathode and anode promoted nitrogen cycling during the reaction process, which improved N2 selectivity of the reaction system and promoted it to achieve a high ammonia removal rate. This study showed that the thin Ni(OH)2 with oxygen vacancy formed on the surface of Ni foam anode played an effective role in the dimerization of intermediate products in ammonia oxidation to form N2. This electrochemical system was used to treat real goose wastewater containing 422.5 mg/L NH4+-N and 94.5 mg/L total organic carbon (TOC). After treatment, this electrochemical system achieved good performance with an ammonia removal rate of 87%, N2 selectivity of 77%, and TOC removal rate of 72%. Therefore, this simple and efficient system with Ni foam anode and Cu foam cathode is a promising method for treating ammonia nitrogen wastewater.


Asunto(s)
Amoníaco , Cobre , Electrodos , Hidróxidos , Níquel , Nitrógeno , Oxidación-Reducción , Amoníaco/química , Nitrógeno/química , Níquel/química , Cobre/química , Hidróxidos/química , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Técnicas Electroquímicas/métodos , Contaminantes Químicos del Agua/química
3.
Artículo en Inglés | MEDLINE | ID: mdl-38668627

RESUMEN

NiFe-layered double hydroxides (NiFe-LDHs), as promising electrocatalysts, have received significant research attention for hydrogen and oxygen generation through water splitting. However, the slow oxidation kinetics of NiFe-LDH, due to the limited number of active sites and the low conductivity, hinders the improvement of the water-splitting efficiency. Therefore, to overcome the obstacles, two-dimensional (2D) SnS was first explored to tailor the prepared NiFe-LDH via the hydrothermal method. A NiFe-LDH/SnS heterojunction is built, which is observed from the microstructural investigations. SnS incorporation could greatly improve the conductivity of the NiFe-LDH sheets, which was reflected by the reduced charge transfer resistance. Moreover, SnS layers modulated the electronic environment around the active sites, favoring the adsorption of intermediates during the oxygen evolution reaction (OER) process, which was verified by density functional theory calculations. A synergistic effect induced by the NiFe-LDH/SnS heterostructure promoted the OER activities in electrical, electronic, and energetic aspects. Consequently, the as-prepared NiFe-LDH/SnS electrocatalyst greatly improved the electrocatalytic performance, exhibiting 20% and 27% reductions in the overpotential and Tafel slope compared with those of pristine NiFe-LDH, respectively. The results provide a strategy for regulating NiFe-based electrocatalysts by using emerging 2D materials to enhance water-splitting efficiency.

4.
Water Sci Technol ; 88(11): 2733-2750, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38096065

RESUMEN

The migration, transformation, and accumulation of dissolved organic matter (DOM) in pore water of sediment cores play a pivotal role in lacustrine carbon cycling. In order to understand the dynamics of DOM in the sediments of large shallow eutrophic lakes, we examined the vertical profiles of DOM and the benthic fluxes of dissolved organic carbon (DOC) in sediment cores located in algae accumulated, dredged, and central areas of eutrophic Lake Taihu, China. Optical properties showed the significant influence of terrestrial inputs on the DOM components of pore water in the algae accumulated area but an abundant accumulation of autochthonous DOM in the central area. The benthic fluxes of DOC ranging from -458.2 to -139.4 mg·m-2·d-1 in the algae accumulated area displayed an opposite diffusion direction to the other two areas. The flux ranges of 9.5-31.2 mg·m-2·d-1 in the dredged area and 14.6-48.0 mg·m-2·d-1 in the central area were relatively smaller than those in the previously reported lake ecosystems with low trophic levels. Dredging engineering disturbed the pre-dredging distribution patterns of DOM in sediment cores. The deposition, accumulation, and transformation of massive algae scums in eutrophic lakes probably promoted the humification degree of sediments.


Asunto(s)
Materia Orgánica Disuelta , Lagos , Agua , Ecosistema , China , Sedimentos Geológicos
5.
Curr Med Imaging ; 2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37553763

RESUMEN

INTRODUCTION: A large jejunal diverticulum has been reported as a possible cause of volvulus and acute mesenteric ischemia (AMI) in adults. A large diverticulum of the small bowel complicated with volvulus has been reported before in literature. However, imaging findings of a large diverticulum of the small bowel complicated with both volvulus and AMI on MDCT are rarely described and reported. In this study, we reported a case with a large diverticulum, volvulus, and AMI concurrently; these three imaging findings were reviewed and described on MDCT, and the relevant literature was briefly introduced. CASE REPORT: We reported the case of a 69-year-old man who presented to our hospital with acute abdominal pain and vomiting. An emergent abdominal enhanced MDCT imaging was performed and demonstrated the volvulus secondary to a large diverticulum of the jejunum complicated with AMI. Here, a case was presented that highlighted unique imaging findings on MDCT, as well as a literature review. CONCLUSION: A review of the literature revealed that a single jejunal diverticulum causing both volvulus and AMI is rare in adults. To our knowledge, a systemic description of their signs on MDCT in a case has not been reported yet.

6.
Foods ; 12(9)2023 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-37174360

RESUMEN

The banana quality evaluation system is not sufficiently mature in China and cannot meet the demand of producing high-quality processed banana products. In order to screen banana varieties suitable for low-temperature vacuum frying and extend the banana deep processing industry chain, banana slices from 15 varieties planted in China were prepared by low-temperature vacuum-frying (VF) technology in the present study. After factor analysis on 20 indicators of sensory, flavor, nutritional and processing quality from different varieties of banana slices, comprehensive quality evaluation models were constructed for banana slices. It was concluded that Meishijiao No. 1 had the highest overall score among the 15 banana varieties; hence, it was deemed suitable for processing. Meanwhile, in order to investigate the difference between flavor substances in banana slices before and after processing, a flavor histology study was conducted with solid-phase microextraction (SPME) and comprehensive two-dimensional gas chromatography coupled to time-of flight mass spectrometry (GC×GC-TOFMS). It was found that the content differences of 2,3-pentanedione, hexanal and pentanal may cause the weakened fruitiness and the increased oil flavor of banana taste.

7.
Food Res Int ; 165: 112531, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36869530

RESUMEN

Mango is one of the most economically important fruit; however, the gene regulatory mechanism associated with ripening and quality changes during storage remains largely unclear. This study explored the relationship between transcriptome changes and postharvest mango quality. Fruit quality patterns and volatile components were obtained using headspace gas chromatography and ion-mobility spectrometry (HS-GC-IMS). The changes in mango peel and pulp transcriptome were analyzed during four stages (pre-harvesting, harvesting, maturity, and overripe stages). Based on the temporal analysis, multiple genes involved in the biosynthesis of secondary metabolites were upregulated in both the peel and pulp during the mango ripening process. Moreover, cysteine and methionine metabolism related to ethylene synthesis were upregulated in the pulp over time. Weighted gene co-expression network analysis (WGCNA) further showed that the pathways of pyruvate metabolism, citrate cycle, propionate metabolism, autophagy, and SNARE interactions in vesicular transport were positively correlated with the ripening process. Finally, a regulatory network of important pathways from pulp to peel was constructed during the postharvest storage of mango fruit. The above findings provide a global insight into the molecular regulation mechanisms of postharvest mango quality and flavor changes.


Asunto(s)
Redes Reguladoras de Genes , Mangifera , Animales , Frutas , Cromatografía de Gases y Espectrometría de Masas , Perfilación de la Expresión Génica , Aves
8.
Front Public Health ; 11: 1087276, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36992893

RESUMEN

Objective: The impact of the aging population in China varies between regions. It is because regions with different resource endowments, such as those related to economy, population, and medical care, have different degrees of disability risk in the face of the increases in the disabled and semi-disabled older population caused by the overall aging of the population. This study aimed to construct an evaluation system to monitor and measure the degree of social disability risk in different regions in China and to evaluate and compare the degree of social disability risk in different regions using empirical data. Method: This study used the Delphi method to construct a social disability risk measurement index system with macro, meso, and micro dimensions. At the same time, based on the data of CHARLS2018, an AHP-entropy method was used to calculate the index's total weight, and the standard deviation classification method was used to classify the total and criterion-level measurement scores of 28 provinces. Results: The regional degree of social disability risk was analyzed in subdimensions. Our research indicates that China's social disability risk situation is not promising, with a general medium to high-risk level. The score of degree of social disability risk among provinces is consistent with the regional economic development level to a large extent. The risk of social disability varies significantly among the eastern and central, and western regions of China and the provinces within the three regions. Discussion: Currently, the situation facing the degree of social disability risk in China is that the overall risk level of the country is higher, and the difference between regions is significant. It is necessary to take measures to meet better the needs of the aging population and the disabled and semi-disabled older populations in a large-range, large-scale, multilevel way.


Asunto(s)
Desarrollo Económico , China/epidemiología
9.
Ann Oper Res ; : 1-22, 2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36777410

RESUMEN

This paper contributes to the integrated design issue of urban and rural logistics networks under demand uncertainty. A hierarchical hub location model is proposed, which minimizes the expected total system cost by optimizing the locations, number and capacities of "urban-town‒village" hierarchical logistics hubs. The interactions among the logistics hubs and among the hub‒and‒spoke connections, as well as the hub capacity constraints are explicitly considered in the presence of logistics demand uncertainty. A demand scenario‒based branch‒and‒Benders‒cut algorithm is developed to solve the proposed model. A case study of Jiangling urban‒rural region in Hubei province of China is conducted for the illustration of the model and solution algorithm. The results generated by the proposed algorithm are benchmarked against those obtained by GUROBI solver and the practical scheme being currently implemented in the region. The results showed that the proposed methodology can greatly improve the efficiency of the urban‒rural logistics system in terms of expected total system cost. It is important to explicitly model the demand uncertainty, otherwise a significant decision bias may emerge. The proposed algorithm outperforms the GUROBI solver in terms of problem size solved and computational time.

10.
Ecotoxicol Environ Saf ; 249: 114434, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38321656

RESUMEN

Nitrate pollution in groundwater is a global environmental concern. As a result, accurate identification of potential sources for such pollution is of critical significance to the effective control of groundwater quality. In this study, forty-nine shallow groundwater samples were collected from the Huaibei mining area. Hydro-chemical characterization, geospatial analysis technique, dual nitrate isotopes (δ15N-NO3- and δ18O-NO3-), Bayesian model and health risk assessment model were adopted for exploring the conditions, sources, proportion, and potential health risks of nitrate pollution for the first time in the study area. The results showed that the nitrate concentration ranged from 0.00 to 293.21 mg/L, and that 18.37% groundwater samples exceeded the standard of drinking water in China (GB 5749-2006). Based on the dual isotopic values of nitrate, it could be concluded that nitrification was dominated migration and transformation process of nitrogen. The results of Bayesian model showed that the proportional contributions of the potential nitrate pollution sources in shallow groundwater were manure and sewage (M&S) (39.54 %), NH4+ in fertilizer and precipitation (NHF&P) (34.93 %), soil nitrogen (SN) (14.89 %), and NO3- in atmospheric deposition (NAD) (10.64 %). The health risk assessment indicated that non-carcinogenic risks posed by NO3--N was higher for children than adults. The primary exposure pathway was oral ingestion. Monte Carlo simulation were applied to evaluate model uncertainty. The probabilities of non-carcinogenic risks were up to 12.54 % for children and 5.22 % for adults. In order to protect water quality and drinking water safety, it was suggested that effective nitrate reduction strategies and better management practices can be implemented.


Asunto(s)
Agua Potable , Agua Subterránea , Contaminantes Químicos del Agua , Niño , Humanos , Nitratos/análisis , Isótopos de Nitrógeno/análisis , Teorema de Bayes , Agua Potable/análisis , Método de Montecarlo , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Nitrógeno/análisis , Agua Subterránea/química , China , Calidad del Agua
11.
Transp Res Part A Policy Pract ; 165: 439-453, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36248723

RESUMEN

This study empirically identifies business travellers' preferences during the COVID-19 pandemic across different regions. A stated preference study was conducted during April to June 2021 on respondents in the U.S., the city of Shanghai in mainland China and Hong Kong. Generalised mixed multinomial logit (GMXL) models are estimated incorporating attributes of travel characteristics, severity levels of the pandemic, and health control measures at the airport. When an online meeting is inapplicable, respondents from Shanghai and Hong Kong highly value heath control measures, and are not sensitive to the time spent at airport health checkpoints. In comparison, U.S. respondents are averse to the time spent for health check, the reporting of personal information, travel history, symptoms, and the requirements of compulsory mask wearing and onsite sample testing. However, when online meeting is applicable, all the respondents show no appreciation for health control measures, while the U.S. respondents are twice more averse to the time spent at airport health checkpoints. Online meeting reduces the intention of international business travel amid the pandemic for passengers in Shanghai and Hong Kong, but imposes no significant effects on U.S. travellers. Such significant heterogeneity in traveller preference partly explains the different recovery patterns observed in various aviation markets, and justifies individualized travel arrangements and service priority in fulfilling pandemic control requirements across different regions. Our study also suggests that there are commonly accepted areas for global cooperation such as the sharing of vaccination record, and the option of online meeting calls for convenient travel arrangements amid pandemic to all countries.

12.
Bull Environ Contam Toxicol ; 109(6): 984-989, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36178504

RESUMEN

Warming has been affecting carbon cycling in freshwater ecosystems throughout recent decades. However, how the co-metabolism effect (CE) during the decomposition of sediment organic carbon (SOC) in eutrophic lakes responds to warming remains understudied. A 33-day experiment was conducted to examine the mechanisms that underpin the CE in lacustrine sediments. The results indicated that warming increased the co-metabolism intensity of sedimentary organic matter. At the beginning of the experiment (0-9 d), the co-metabolism intensity increased rapidly at both 25℃ and 35℃. However, at the end of the experiment (33 d), the cumulative co-metabolism intensity was highest at 25℃, which was 33.75% and 153.74% higher than the intensities at 15℃ and 35℃, respectively. By enhancing the co-metabolism intensity of the SOC, warming would weaken lakes "carbon sink" functions. Thus, our study provides novel evidence that microorganisms regulate SOC turnover and effectively maintain a balance between resources and microbial requirements.


Asunto(s)
Carbono , Lagos , Ecosistema , Secuestro de Carbono
13.
Transp Res E Logist Transp Rev ; 164: 102823, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35945969

RESUMEN

This study quantifies the effects of health control measures at the airport on passenger behaviour related to business travel. A stated preference survey was conducted over potential air travellers in Hong Kong in the context of COVID-19 pandemic. Panel latent class models were estimated to understand passenger preference toward new travel requirements given the applicability of online meeting. Online meeting is applicable in cases where it is a good substitute of air travel and achieves the same outcomes of a trip, and inapplicable otherwise. Empirical results indicate that traveller subgroups are affected in different ways. When an online meeting is inapplicable, nearly 75% of the respondents prefer to travel for business and undertake health screenings. These passengers (identified as "captive" business travellers) perceive such measures necessary to lower health related risks during air travel. As such, they are willing to spend up to 21 to 38 min on the health control measures such as vaccination record requirements and test involving sample collection. When an online meeting is applicable, the share of "choice" business travellers is about 45%, among whom the attitudes towards health control measures become more averse. The average weighted willingness-to-pay for the time saved at health checkpoints increase significantly. The aviation industry thus faces a "double-hit" problem: operation costs will increase due to pandemic control measures, and the resultant inconvenience, extra time and costs further reduces travel demand. Unlike previous short pandemics, business travel is likely to suffer with an extended decline until the pandemic is fully controlled. These identified challenges call for financial and operational support to help the aviation industry reach a sustainable "new normal". The high value of time saved at check points also justifies investments that make the pandemic control and health measures efficient and smooth. Travellers' time spent on airport health control should be within 20 min to avoid substantial negative impacts on business travel demand.

14.
Contrast Media Mol Imaging ; 2022: 3104879, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36043147

RESUMEN

Objective: To explore the effects of cyclophosphamide combined with vinorelbine in advanced small cell lung cancer (SCLC) and anteroposterior changes in MRI. Methods: The clinical data of 90 patients with advanced SCLC admitted to our hospital from April 2020 to April 2021 were retrospectively analyzed. They were divided into the control group and the study group according to the order of admission, with 45 cases in each group. The control group received the routine treatment, while the study group was treated with cyclophosphamide and vinorelbine to compare the indexes of imaging data and clinical indicators between the two groups before and after treatment. Results: There was no significant difference in the indexes of imaging data between the two groups before treatment (P > 0.05), and the indexes of imaging data in the study group were visibly lower than those in the control group after treatment (P < 0.001). The DCR in the study group was significantly higher than that in the control group after treatment (P < 0.05), while the QLQ-C30 scores and serum indices of the study group after treatment were significantly lower than those of the control group (P < 0.001). Conclusion: Patients with advanced SCLC were treated with cyclophosphamide and vinorelbine, which can effectively improve the quality of life and reduce the expression of inflammatory factors. This treatment model has a higher application value, and the treatment value is also reflected compared with the routine treatment. At the same time, the permeability parameters obtained by MRI can predict the therapeutic effects of cyclophosphamide and vinorelbine, and further studies are helpful to establish a better solution for patients.


Asunto(s)
Neoplasias Pulmonares , Carcinoma Pulmonar de Células Pequeñas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ciclofosfamida/uso terapéutico , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/tratamiento farmacológico , Imagen por Resonancia Magnética , Calidad de Vida , Estudios Retrospectivos , Carcinoma Pulmonar de Células Pequeñas/diagnóstico por imagen , Carcinoma Pulmonar de Células Pequeñas/tratamiento farmacológico , Vinblastina/uso terapéutico , Vinorelbina/uso terapéutico
15.
Front Nutr ; 9: 894438, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35811964

RESUMEN

This study aimed to promote red pitaya fruit parts as alternate sources of nutraceuticals. The red pitaya of Chinese origin was determined for its in vitro efficacy, where the fruit extracts were evaluated based on the selected antioxidative properties, lipid-reducing capacity, and cytotoxicity. The betanin, total betacyanins, total anthocyanins, and DPPH radical scavenging activity of the red pitaya pulp and peel extracts were determined by spectrophotometric analyses. Cell culture assays were used to examine in vitro efficacy and cytotoxicity of the pitaya extracts. The result showed that red pitaya peel extract had a higher total betacyanins and total anthocyanins content than the pulp extract, but the peel extract had a lower DPPH radical scavenging effect than the pulp extract. The red pitaya extracts also had a protective effect in reducing oxidative stress, especially the peel extract. All fruit samples had a low anticancer potential except for betanin and anthocyanin standards. The protective effect of pitaya peel could be attributed to betacyanins and anthocyanins. Both pulp and peel extracts had a weak anticancer effect because these extracts contained polysaccharides and other phytochemicals that were not cytotoxic. As the peel extract of red pitaya was not cytotoxic, it is a potent source of betacyanins for reducing oxidative stress.

16.
Sci Total Environ ; 838(Pt 3): 156402, 2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-35660575

RESUMEN

Fine particulate matter (PM2.5) has drawn more and more interest due to its adverse effects on health. Thyroid has been demonstrated to be the key organ impacted by PM2.5. However, the mechanisms for PM2.5 exposure-induced thyrotoxicity remain unclear. To explore the mechanisms, a rat thyroid injury model was established by exposing rats to PM2.5 via passive pulmonary inhalation. Thyroid hormones and thyroid function proteins were detected. The thyroid function affected by PM2.5 exposure was investigated via metabolomics analysis using liquid chromatography-mass spectrometry and 16S rRNA gene sequencing. Results showed that PM2.5 exposure induced remarkable alterations in gut microbiome evenness, richness, and composition. Metabolomics profiling revealed that the urine metabolites levels were changed by PM2.5 exposure. The altered gut microbiota and urine metabolites showed significant correlations with thyroid function indicators (total T3, total T4 and thyrotropin hormone, etc.). These metabolites were involved in metabolic pathways including thyroid hormone synthesis, metabolisms of tryptophan, d-Glutamine and D-glutamate, histidine, glutathione, etc. The altered gut microbiota showed significant correlations with urine metabolites (glutathione, citric acid, D-Glutamic acid, kynurenic acid and 5-Aminopentanoic acid, etc.). For example, the taurocholic acid levels positively correlated with the relative abundance of several genera including Elusimicrobium (r = 0.9741, p = 0.000000), Muribaculum (r = 0.9886, p = 0.000000), Candidatus_Obscuribacter (r = 0.8423, p = 0.000585), Eubacterium (r = 0.9237, p = 0.000017), and Parabacteroides (r = 0.8813, p = 0.000150), while it negatively correlated with the relative abundance of Prevotella (r = -0.8070, p = 0.001509). PM2.5 exposure-induced thyrotoxicity led to remarkable alterations both in gut microbiome composition and some metabolites involved in metabolic pathways. The altered intestinal flora and metabolites can in turn influence thyroid function in rats. These findings may provide novel insights regarding perturbations of the gut-thyroid axis as a new mechanism for PM2.5 exposure-induced thyrotoxicity.


Asunto(s)
Microbioma Gastrointestinal , Animales , Glutatión/metabolismo , Metaboloma , Material Particulado/toxicidad , ARN Ribosómico 16S/genética , Ratas , Glándula Tiroides/metabolismo
17.
Artículo en Inglés | MEDLINE | ID: mdl-35666991

RESUMEN

The electrocatalytic nitrogen reduction reaction (NRR) to NH3 is limited by low Faradaic efficiency (FE). Herein, defective UiO-66-NH2 functionalized with quite stable superoxide radicals (O2•) is developed as a highly active NRR catalyst. The experimental and computational results show that one linker per Zr6 node is missed and two Zr atoms are exposed in the defective UiO-66-NH2. One of the two exposed Zr atoms can stably adsorb O2•, and thus, a Zr-OO• site forms during the preparations without light excitation or postoxidation, while the other Zr atom is activated as an active site. The synergistic effects of the two Zr sites in the defective UiO-66-NH2 suppress hydrogen and hydrazine evolutions considerably. They are as follows: (i) due to repulsion of the proton on the active Zr site and stabilization of the proton on the Zr-OO• site, the active Zr site is unfavorable for the adsorption of the proton with a high energy barrier, which is the HER rate-determining step (RDS); (ii) under the assistance of the OO• of the Zr-OO• site, the first hydrogenation step of *N2 (i.e., NRR RDS) on the active Zr site is promoted; and (iii) relying on the assistance of the OO• of the Zr-OO• site, the continuous hydrogenation of *NH2NH2 to produce NH3 on the active Zr site is spontaneously exothermic, whereas its desorption to hydrazine is blocked. Accordingly, an extremely high FE of ∼85.21% has been realized along with a high yield rate of NH3 (∼52.81 µg h-1 mgcat-1). To the best of our knowledge, it is the highest FE that has been achieved in recent years. Radical scavenging treatment of the defective UiO-66-NH2 and detailed investigations of two categories of control samples further verify the favorable effects of the O2• that closely correlates with the missed linkers on the performance of the NRR to NH3. This work opens a new way toward highly efficient NRR catalysts, i.e., stable radical-activating defective metal-organic frameworks.

18.
Spectrochim Acta A Mol Biomol Spectrosc ; 276: 121218, 2022 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-35429858

RESUMEN

In this subject, a novel hydrogen peroxide (H2O2) fluorescent probe (MNG) was designed and developed using naphthalimide derivatives and selenomorpholine. In PBS buffer (10 mM, pH = 7.4, 1 %DMSO), the selenomorpholine on the probe is capable of qualitatively and quantitatively detecting (H2O2) at a small amount under a detection limit of 61 nM. The probe follows a mechanism that Se (Ⅱ) in selenomorpholine is transformed to Se (Ⅳ), thus changing the spectra of the probe MNG. It is noteworthy that MNG can continuously make a cyclic response to H2O2 and glutathione (GSH), so it can potentially achieve redox process imaging in vivo. Moreover, this subject verified the redox process of the probe's continuous redox response in the Gaussian 09 programme through simulation calculation and mass spectrometry. The probe exhibits high biocompatibility. Moreover, it can detect H2O2 in MCF-7 cells and Argentine Bloodfin.


Asunto(s)
Colorantes Fluorescentes , Peróxido de Hidrógeno , Colorantes Fluorescentes/química , Glutatión/análisis , Peróxido de Hidrógeno/análisis , Naftalimidas , Oxidación-Reducción
19.
Bioorg Chem ; 123: 105798, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35413581

RESUMEN

Abnormal intracellular hydrogen peroxide (H2O2) concentration is related to cancer, cardiovascular, cerebrovascular diseases and other diseases. A novel H2O2 fluorescent probe (BBS) was designed and synthesized. The fluorescence intensity shows good linear relationship with the concentration of H2O2 (0-40 µM), and the detection limit is 132 nM. The response mechanism of probe BBS was verified and analyzed by UV-Vis spectra, titration spectra and density functional theory (DFT) on Gaussian 09 programme. BBS can be used for bioimaging in living cells.


Asunto(s)
Colorantes Fluorescentes , Peróxido de Hidrógeno , Benzotiazoles , Células HeLa , Humanos
20.
Ann Transl Med ; 10(24): 1382, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36660719

RESUMEN

Background: Interferon-α-1b, interleukin-2 combined with thalidomide (ITI) improved the outcome and prognosis of some acute myeloid leukemia (AML) patients, but the cases was insufficient. This study observed the efficacy and safety of this regimen in the treatment of numbers of AML patients in various disease states. Methods: Starting in January 2014, patients with AML (n=188) were treated with ITI regimen, including 60 refractory/relapses patients in group A, 40 patients in group B remained minimal residual disease-positive (MRD) or changed from negative to positive again after consolidation therapy, and 88 patients in group C with initial complete remission of AML received the ITI treatment after routine consolidation therapy. Bone marrow, fusion gene and MRD were detected to judge the curative effect and the adverse reactions were observed. The remission rate, MRD status and long-term survival of three groups were analyzed. An AML mouse model was constructed to observe the anti-leukemia effect of the three drugs in vivo. Results: Sixty patients with primary AML who were unable to receive chemotherapy, or with relapsed/refractory AML, showed a total response rate of 28.3% (17/60) after receiving the ITI regimen. Forty patients with morphologically complete remission and MRD-positive achieved a response rate of 77.5% (31/40); the MRD converted to negative in 19 patients and was mitigated in 12 patients. Among 88 patients with initial complete remission, 11 failed to maintain the negative MRD, and the relapse rate was 12.5%, which was significantly lower than that of the non-maintenance treatment group (54.3%). In the mouse model, interferon, interleukin-2, and thalidomide exerted an anti-leukemia effect, prolonged the survival time of the mice, and the anti-leukemia effect was further enhanced after administration of the combination ITI regimen. Conclusions: For suitable patients, hematopoietic stem cell transplantation is still strong recommended. The ITI regimen may be an effective option for patients with AML who cannot tolerate conventional chemotherapy, including those with relapsed/refractory disease, those with a complete remission status but are MRD-positive, or those who require maintenance treatment after consolidation therapy. However, a rigorous clinical randomized controlled trial and more in-depth mechanism exploration are still needed to verify this conclusion.

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