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1.
Inorg Chem ; 63(9): 4152-4159, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38372260

RESUMEN

The template-directed strategy has been extensively employed for the construction of supramolecular architectures. However, with the increase in the size and complexity of these structures, the synthesis difficulty of the templates escalates exponentially, thereby impeding the widespread application of this strategy. In this study, two truncated triangles T1 and T2 were successfully self-assembled through a novel segmented template strategy by segmenting the core triangular template into portions. Two metallo-organic ligands L2 and L3 were designed and synthesized by dividing the central stable triangle into three separate parts and incorporating them into the precursor ligands, which served as templates to guide the self-assembly process with ligands L1 and L4, respectively. The assembled structures were unambiguously characterized by multidimensional and multinuclear NMR (1H, COSY, NOESY), multidimensional mass spectrometry analysis (ESI-MS and TWIM-MS), and transmission electron microscopy (TEM). Moreover, we observed the formation of fiberlike nanotubes from single-molecule triangles by hierarchical self-assembly.

2.
Biomed Chromatogr ; 38(7): e5876, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38600635

RESUMEN

The two-step preconcentration technique consisting of large-volume sample stacking (LVSS) and micelle to solvent stacking (MSS) in cyclodextrin-modified electrokinetic chromatography (CDEKC) was developed for the analysis of five cationic alkaloids in complex Chinese herbal prescriptions. Relevant parameters affecting separation and stacking performance were optimized separately. Under the optimal LVSS-MSS-CDEKC conditions, less analysis time and organic solvent were required, and the enhancement factors of analytes ranged from 12 to 15 compared with the normal CDEKC separation mode. Further, all validation results demonstrated good applicability and multiple alkaloids (epiberberine, dehydrocorydaline, jatrorrhizine, coptisine and berberine) in Yangxinshi tablet (YXST) have been simultaneously determined. This approach presents powerful potential for the determination of multiple components in complex preparations of Chinese medicine.


Asunto(s)
Alcaloides , Cromatografía Capilar Electrocinética Micelar , Medicamentos Herbarios Chinos , Comprimidos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Cromatografía Capilar Electrocinética Micelar/métodos , Comprimidos/química , Alcaloides/análisis , Alcaloides/química , Reproducibilidad de los Resultados , Micelas , Modelos Lineales , Ciclodextrinas/química , Límite de Detección
3.
Phytochem Anal ; 35(5): 1123-1133, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38462488

RESUMEN

INTRODUCTION: Yangxinshi tablet (YXST) is a traditional Chinese medicine preparation characterized by its high efficacy and safety for the treatment of cardiovascular diseases. Anionic compounds have been revealed as potential active components. However, there is currently limited research regarding its quality control. OBJECTIVE: We aimed to establish a strategy for the simultaneous separation and determination of five key anionic compounds in YXST. METHOD: A sensitive and efficient analytical method was developed and applied for the simultaneous separation and determination of five key compounds in YXST using large-volume sample stacking with polarity switching and micelle electrokinetic chromatography (LVSS-PS-MEKC) coupled with diode array detection. Crucial parameters, including sample volume, applied voltage, composition and pH of the running buffer, concentration of organic modifier, and switching time of the polarity, were systematically evaluated and optimized using a single variable method to enhance separation performance. Furthermore, the impact of cyclodextrin and sodium dodecyl sulfate as electrolyte modifiers was also investigated. RESULTS: Under the optimal conditions, baseline separation of the five compounds (daidzein, puerarin, glycyrrhiztinic acid, chlorogenic acid, and salvianolic acid B) was achieved within 20 min. In comparison to the conventional MEKC mode, the constructed LVSS-PS-MEKC method exhibited a more than sixfold increase in the enrichment factor. The method was validated in terms of linearity, precision, accuracy, 24 h stability, and recovery and successfully applied to analyze YXST samples. CONCLUSION: A sensitive strategy was developed for the simultaneous separation and determination of five key anionic components in YXST, offering a robust and efficient strategy for pharmaceutical analysis.


Asunto(s)
Aniones , Cromatografía Capilar Electrocinética Micelar , Medicamentos Herbarios Chinos , Comprimidos , Cromatografía Capilar Electrocinética Micelar/métodos , Comprimidos/química , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Reproducibilidad de los Resultados , Dodecil Sulfato de Sodio/química
4.
Environ Res ; 238(Pt 2): 117260, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37775012

RESUMEN

An environmentally friendly strategy was used in this study to synthesize gold nanoparticles decorated on sepiolite clay (GNPs-SC) using Heracleum persicum grass extract. The physicochemical characters of the prepared composite were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). A GNPs-SC modified carbon pate electrode (CPE) was used to study the electrochemical oxidation of nitrite. The proposed nitrite sensor exhibits excellent performance, including a broad linear range (1.0-150 µM), a low limit of detection (0.4 µM), and acceptable reproducibility (RSD = 2.6%). As well, the prepared GNPs-SC was tested for its effectiveness against human gastric adenocarcinoma (AGS) cell line. The MTT assay protocol revealed that the bio-synthesized product displayed significant cytotoxic activity against gastric cancer in human subjects. The findings of this study indicate that GNPs-SC, synthesized using environmentally friendly protocol, exhibit great potential for use in electrochemical sensing and treatment of human cancer.


Asunto(s)
Nanopartículas del Metal , Neoplasias Gástricas , Humanos , Oro/química , Nitritos/análisis , Arcilla , Nanopartículas del Metal/química , Reproducibilidad de los Resultados
5.
J Sep Sci ; 46(13): e2300054, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37029534

RESUMEN

An in-capillary 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate) as oxyradicals combining field-enhanced sample injection with micellar electrokinetic chromatography was developed for screening and determination of the major antioxidants in Yangxinshi Tablet. To obtain simultaneous separation and detection of radicals and analytes, relevant factors were optimized separately. Under the optimum conditions, four compounds including salvianolic acid B, hyperoside, puerarin, and caffeic acid were identified as the major antioxidants. All validation results covering recovery, precision, and stability demonstrated good applicability of the method. On this basis, the total antioxidant activity was successfully evaluated in terms of the decreased peak area of radicals. There was a correlation coefficient of 0.8974 between the total contents of major antioxidants and the total antioxidative activity of the sample. Therefore, these four compounds were selected as combinatorial markers for the quality evaluation of Yangxinshi Tablet. It was concluded that the established method presented a powerful potential to screen and quantify active ingredients in the complex preparation of Chinese medicine.


Asunto(s)
Cromatografía Capilar Electrocinética Micelar , Medicamentos Herbarios Chinos , Antioxidantes/análisis , Micelas , Medicamentos Herbarios Chinos/análisis , Cromatografía Capilar Electrocinética Micelar/métodos
6.
Altern Ther Health Med ; 29(7): 434-439, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37573587

RESUMEN

Objective: This study sought to identify candidate genes of rheumatoid arthritis (RA) synovial macrophages using bioinformatics and to explore their pathways in the pathogenesis of RA. Methods: The microarray datasets GSE10500 and GSE97779 were obtained from the Gene Express Omnibus and analyzed with synovial macrophages of 14 RA patients and 8 healthy donors. The researchers used R software to identify differentially expressed genes and determine functional enrichment pathways. A protein-protein interaction network was then constructed using STRING and Cytoscape. Gene expression was validated with the GSE71370 dataset and RT-qPCR analysis. Results: 102 DEGs were identified in RA synovial macrophages relative to normal samples. Of these, 72 were upregulated; 30 were downregulated. GO and KEGG pathway analyses suggested that DEGs mainly regulated the immune response and signaling pathways associated with inflammatory activation, apoptosis, and cancer. The top five hub genes and top 1 gene module from the PPI network of DEGs were VEGFA, MMP9, FN1, IGF1, CXCL9, ISG20, RSAD2, IFI27, GBP2, and GBP1. The GSE71370 dataset and RT-qPCR analysis showed that CXCL9 and GBP1 were significantly upregulated (P ≤ .05). Conclusions: CXCL9 and GBP1 may contribute to RA pathogenesis and serve as potential biomarkers and therapeutic targets for RA.


Asunto(s)
Artritis Reumatoide , Perfilación de la Expresión Génica , Humanos , Transcriptoma , Artritis Reumatoide/genética , Mapas de Interacción de Proteínas/genética , Redes Reguladoras de Genes
7.
Arch Gynecol Obstet ; 308(1): 63-71, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-35913558

RESUMEN

Systemic lupus erythematosus (SLE)-a most common disorder in women of reproductive age-has been described to be associated with adverse pregnancy outcomes. Despite the increased health risks for the mother (preeclampsia, lupus flare, arterial hypertension, gestational diabetes mellitus and thrombotic risk when antiphospholipid antibodies are present) and fetus (miscarriage, stillbirth, premature birth, intrauterine growth restriction and neonatal lupus), the majority of patients can deliver healthy neonates. With appropriate management by a multidisciplinary team, composing rheumatologists, obstetricians and neonatologists, women with SLE can achieve better pregnancy outcomes by monitoring associated predictive indicators, raising major concern for severe complications and somewhat early delivery if necessary. In this review, we summarize the latest advances in secondary infertility and pregnancy-related risk perception for lupus patients, with an emphasis on the safety of biological agents (mainly belimumab and rituximab) and traditional therapeutic regimens.


Asunto(s)
Lupus Eritematoso Sistémico , Complicaciones del Embarazo , Embarazo , Recién Nacido , Humanos , Femenino , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/tratamiento farmacológico , Brote de los Síntomas , Resultado del Embarazo , Complicaciones del Embarazo/tratamiento farmacológico , Anticuerpos Antifosfolípidos/uso terapéutico
8.
BMC Biol ; 20(1): 287, 2022 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-36528592

RESUMEN

BACKGROUND: Inflammatory bowel diseases (IBDs) are characterized by sustained inflammation and/or ulcers along the lower digestive tract, and have complications such as colorectal cancer and inflammation in other organs. The current treatments for IBDs, which affect 0.3% of the global population, mainly target immune cells and inflammatory cytokines with a success rate of less than 40%. RESULTS: Here we show that berberine, a natural plant product, is more effective than the frontline drug sulfasalazine in treating DSS (dextran sulfate sodium)-induced colitis in mice, and that berberine not only suppresses macrophage and granulocyte activation but also promotes epithelial restitution by activating Lgr5+ intestinal stem cells (ISCs). Mechanistically, berberine increases the expression of Wnt genes in resident mesenchymal stromal cells, an ISC niche, and inhibiting Wnt secretion diminishes the therapeutic effects of berberine. We further show that berberine controls the expression of many circadian rhythm genes in stromal cells, which in turn regulate the expression of Wnt molecules. CONCLUSIONS: Our findings suggest that berberine acts on the resident stromal cells and ISCs to promote epithelial repair in experimental colitis and that Wnt-ß-Catenin signaling may be a potential target for colitis treatment.


Asunto(s)
Berberina , Colitis , Ratones , Animales , Berberina/farmacología , Berberina/uso terapéutico , Sulfato de Dextran/efectos adversos , Modelos Animales de Enfermedad , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Células Madre/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Mucosa Intestinal/metabolismo
9.
Mikrochim Acta ; 190(6): 244, 2023 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-37247003

RESUMEN

A photoelectrochemical molecular imprinting sensor based on Au/TiO2 nanocomposite was constructed for the detection of dibutyl phthalate. Firstly, TiO2 nanorods were grown on fluorine-doped tin oxide substrate by hydrothermal method. Then, gold nanoparticles were electrodeposited on TiO2 to fabricate Au/TiO2. Finally, molecular imprinted polymer was electropolymerized on the Au/TiO2 surface to construct MIP/Au/TiO2 PEC sensor for DBP. The conjugation effect of MIP accelerates the electron transfer between TiO2 and MIP, which can greatly improve the photoelectric conversion efficiency and sensitivity of the sensor. In addition, MIP can also provide sites for highly selective recognition of dibutyl phthalate molecules. Under optimal experimental conditions, the prepared photoelectrochemical sensor was used for the quantitative determination of DBP and the results showed a wide linear range (50 to 500 nM), a low limit of detection (0.698 nM), and good selectivity. The sensor was used in a study of real water samples to show that it has promising applications in environmental analysis.

10.
Chin J Physiol ; 66(1): 14-20, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36814152

RESUMEN

Aging with dysregulated metabolic and immune homeostasis stimulates pyroptosis, neuroinflammation, and cellular senescence, thus contributing to etiopathogenesis of Alzheimer's disease. GATA-binding protein 4 (GATA4) functions as a transcriptional factor in response to DNA damage, and is associated with neuroinflammation and cellular senescence. The role of GATA4 in Alzheimer's disease was investigated. GATA4 was elevated in hippocampus of Aß1-42 fibril-infused rats. Injection with shRNA targeting GATA4 reduced escape latency with increase of time in target quadrant and number of platform crossings in Aß1-42 fibril-infused rats. Moreover, knockdown of GATA4 ameliorated morphological changes of hippocampus and reduced amyloid plaque deposition in Aß1-42 fibril-infused rats. Silence of GATA4 repressed neuroinflammation and apoptosis in Aß1-42 fibril-infused rats. Loss of GATA4 in Aß1-42 fibril-infused rats reduced the expression of specificity protein 1 (Sp1) to downregulate long noncoding RNA small nucleolar RNA host gene 1 (SNHG1) and upregulated miR-361-3p. Loss of SNHG1 ameliorated learning and memory impairments in Aß1-42 fibril-infused rats. Overexpression of Sp1 attenuated GATA4 silence-induced decrease of escape latency, increase of time in target quadrant, and number of platform crossings in Aß1-42 fibril-infused rats. In conclusion, silence of GATA4 ameliorated cognitive dysfunction and inhibited hippocampal inflammation and cell apoptosis through regulation of Sp1/SNHG1/miR-361-3p.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Factor de Transcripción GATA4 , MicroARNs , Animales , Ratas , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , MicroARNs/genética , Enfermedades Neuroinflamatorias , ARN Nucleolar Pequeño , Factor de Transcripción GATA4/metabolismo
11.
J Am Chem Soc ; 144(46): 21328-21336, 2022 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-36350764

RESUMEN

Artificial photosynthesis of H2O2 from O2 reduction provides an energy-saving, safe, and green approach. However, it is still critical to develop highly active and selective 2e- oxygen reduction reaction photocatalysts for efficient H2O2 production owing to the unsatisfactory photosynthesis productivity. Herein, two new two-dimensional piperazine-linked CoPc-based covalent organic frameworks (COFs), namely, CoPc-BTM-COF and CoPc-DAB-COF, were afforded from the nucleophilic substitution reaction of hexadecafluorophthalocyaninato cobalt(II) (CoPcF16) with 1,2,4,5-benzenetetramine (BTM) or 3,3'-diaminobenzidine (DAB). Powder X-ray diffraction analysis in combination with electron microscopy and a series of spectroscopic technologies reveals their crystalline porous framework with a fully conjugated structure and eclipsed π-stacking model. Ultraviolet-visible diffuse reflectance absorption spectra unveil their excellent light absorption capacity in a wide range of 400-1000 nm. This, together with their enhanced photo-induced charge separation and transport efficiency as disclosed by photocurrent response and photoluminescence measurements, endows the as-prepared piperazine-linked CoPc-based COFs with superior photocatalytic activity toward O2-to-H2O2 conversion under visible-light irradiation (λ > 400 nm). In particular, CoPc-BTM-COF exhibits a record-high H2O2 yield of 2096 µmol h-1 g-1 among the COF-based photocatalysts and an impressive apparent quantum yield of 7.2% at 630 nm. The present result should be helpful for fabricating high-performance and low-cost photocatalysts for visible-light-driven H2O2 photosynthesis.


Asunto(s)
Peróxido de Hidrógeno , Luz , Piperazina , Fotosíntesis
12.
Small ; 18(18): e2201314, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35363425

RESUMEN

It is still a challenging target to achieve photocatalytic CO2 conversion to valuable chemicals with H2 O as an electron donor. Herein, 2D imide-based covalent organic polymer nanosheets (CoPcPDA-CMP NSs), which integrate cobalt phthalocyanine (CoPc) moiety for reduction half-reaction and 3,4,9,10-perylenetetracarboxylic diimide moiety for oxidation half-reaction, are constructed as a Z-scheme artificial photosynthesis system to complete the overall CO2 reduction reaction. Owing to the outstanding light absorption capacity, charge separation efficiency, and electronic conductivity, CoPcPDA-CMP NSs exhibit excellent photocatalytic activity to reduce CO2 to CO using H2 O as a sacrificial agent with a CO production rate of 14.27 µmol g-1 h-1 and a CO selectivity of 92%, which is competitive to the state-of-the-art visible-light-driven organic photocatalysts towards the overall CO2 reduction reaction. According to a series of spectroscopy experiments, the authors also verify the photoexcited electron transfer processes in the CoPcPDA-CMP NSs photocatalytic system, confirming the Z-scheme photocatalytic mechanism. The present results should be helpful for fabricating high-performance organic photocatalysts for CO2 conversion.


Asunto(s)
Dióxido de Carbono , Polímeros , Dióxido de Carbono/química , Catálisis , Citidina Monofosfato , Luz
13.
Int J Immunogenet ; 49(3): 193-201, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35253998

RESUMEN

Systemic Juvenile Idiopathic Arthritis (sJIA) is a distinctive subtype of Juvenile Idiopathic Arthritis (JIA). The pathogenesis of sJIA is still unclear with the limited treatment options. Although previous bioinformatics analyses have identified some genetic factors underlying sJIA, these studies were mostly single centre with a small sample size and the results were often inconsistent. Herein, we combined two data sets of GSE20307 and GSE21521 and select the matrix of patients diagnosed as sJIA in it for further analysis. The GSE20307 and GSE21521 matrixes downloaded from the Gene Expression Omnibus (GEO) were analysed using online tools GEO2R, Venny, Metascape, STRING and Cytoscape to identify differentially expressed genes (DEGs), enrichment pathways, protein-protein interaction (PPI), main module and hub genes between sJIA individuals and healthy controls. A total of 289 overlapping genes (consisting of 41 downregulated genes and 248 upregulated genes) were identified. Hub genes were primarily related to erythropoiesis. And the KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis of overlapping DEGs were mainly involved in malaria and non-small cell lung cancer. Besides, DEGs in main module were involved in ubiquitin-mediated proteolysis. Our study suggests that the erythropoiesis signature indeed exists in sJIA similar to previous reports. And ubiquitin-mediated proteolysis is important in sJIA.


Asunto(s)
Artritis Juvenil , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Artritis Juvenil/genética , Artritis Juvenil/patología , Biología Computacional/métodos , Eritropoyesis/genética , Perfilación de la Expresión Génica/métodos , Humanos , Proteolisis , Ubiquitina/genética , Ubiquitina/metabolismo
14.
Mikrochim Acta ; 189(12): 453, 2022 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-36411347

RESUMEN

A photoelectrochemical (PEC) aptasensor based on CdSe@SnS2 nanocomposite has been developed to detect sulfamethazine (SMZ). The introduction of CdSe into SnS2 displayed an amplified PEC signal, which was higher than that of pure CdSe and SnS2, attributable to its enhanced light harvesting capacity and promoted PEC energy conversion efficiency. Due to the formation of specific non-covalent bonds, the SMZ-binding aptamer (SBA) has significant specificity and sensitivity. When SMZ was incubated on a CdSe@SnS2 modified electrode fixed with aminated SBA, the formation of the SMZ/SBA complex increased the space resistance of electron transfer and hindered the electronic migration between the electrodes, resulting in a decrease in photocurrent. The greater the adsorbed amount on the SBA, the lower the photocurrent produced.  Under optimized conditions the photocurrent response of MCH/SBA/CdSe@SnS2/FTO was inversely proportional to the SMZ concentration in the range 0.1 to 100 pM, with a detection limit (3 S/N) of 0.025 pM (at 0 V vs. Hg/HgCl). The recoveries ranged from 95.8 to 104% with relative standard deviations (RSDs) < 6.3% (n = 3) in actual water sample. This PEC aptasensor which shows considerable potential in SMZ detection applications has high selectivity, reproducibility, and good stability.


Asunto(s)
Técnicas Biosensibles , Compuestos de Cadmio , Nanocompuestos , Compuestos de Selenio , Sulfametazina , Compuestos de Cadmio/química , Técnicas Electroquímicas/métodos , Técnicas Biosensibles/métodos , Reproducibilidad de los Resultados , Titanio/química , Compuestos de Selenio/química , Nanocompuestos/química
15.
Int J Mol Sci ; 23(10)2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35628563

RESUMEN

CRISPR/Cas system has developed a new technology to modify target genes. In this study, CasΦ2 is a newly Cas protein that we used for genome modification in Arabidopsis and tobacco. PDS and BRI1 of marker genes were chosen for targeting. CasΦ2 has the function to cleave pre-crRNA. In the presence of 10 mM Mg2+ irons concentration, sgRNA3 type guided CasΦ2 to edit target gene and generate mutation, and a mutant seedling of AtBRI1 gene with an expected male sterile phenotype was obtained. In the process of tobacco transformation, the gene editing activity of CasΦ2 can be activated by 100 nM Mg2+ irons concentration, and sgRNA1 type guided CasΦ2 to edit target gene. Mutant seedlings of NtPDS gene with an expected albino were obtained. The results indicate that CasΦ2 can effectively edit target genes under the guidance of different sgRNA type in the presence of Mg2+ ions. Together, our results verify that the CRISPR/CasΦ2 system is an effective and precise tool for genome editing in plants.


Asunto(s)
Arabidopsis , Edición Génica , Arabidopsis/genética , Sistemas CRISPR-Cas/genética , Mutación , Plantas/genética , Nicotiana/genética
16.
J Environ Manage ; 304: 114217, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34883435

RESUMEN

COVID-19 has spread worldwide, leading to a significant impact on daily life. Numerous studies have confirmed that people have changed their travel to urban green spaces during the COVID-19 pandemic. However, in China, where COVID-19 has been effectively controlled, how the travel behavior of visitors to urban parks has changed under different risk levels (RLs) of COVID-19 is unclear. Faced with these gaps, we took a highly developed city, Wuhan, as a case study and a questionnaire survey was conducted with 3276 respondents to analyze the changes in park visitors' travel behaviors under different COVID-19 RLs. Using a stated preference (SP) survey method, four RLs were assigned: new cases in other provinces (RL1), Hubei province (RL2), Wuhan (RL3), and in the district of the park (RL4). The results indicated that visitors reduced their willingness to visit urban parks, with 78.39%, 37.97%, and 13.34% of visitors remaining under RL2, RL3, and RL4, respectively. Furthermore, the service radius of urban parks also shrank from 4230 m under no new cases of COVID-19 to approximately 3000 m under RL3. A higher impact was found for visitors using public transport, those with a higher income and higher education, and female visitors. Based on the modified travel behaviors, the Gaussian-based two-step floating catchment area (2SFCA) method was used to evaluate the accessibility and the Gini coefficient was calculated to represent the equality of the urban parks. A higher RL led to lower accessibility and greater inequitable access. The results should help the government guide residents' travel behaviors after COVID-19.


Asunto(s)
COVID-19 , Parques Recreativos , China , Femenino , Humanos , Pandemias , SARS-CoV-2 , Viaje
17.
J Am Chem Soc ; 143(18): 7104-7113, 2021 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-33939427

RESUMEN

The rapid development in synthesis methodology and applications for covalent organic frameworks (COFs) has been witnessed in recent years. However, the synthesis of highly stable functional COFs still remains a great challenge. Herein two-dimensional polyimide-linked phthalocyanine COFs (denoted as CoPc-PI-COF-1 and CoPc-PI-COF-2) have been devised and prepared through the solvothermal reaction of the tetraanhydrides of 2,3,9,10,16,17,23,24-octacarboxyphthalocyaninato cobalt(II) with 1,4-phenylenediamine and 4,4'-biphenyldiamine, respectively. The resultant CoPc-PI-COFs with a four-connected sql net exhibit AA stacking configurations according to powder X-ray diffraction studies, showing permanent porosity, thermal stability above 300 °C, and excellent resistance to a 12 M HCl aqueous solution for 20 days. Current-voltage curves reveal the conductivity of CoPc-PI-COF-1 and CoPc-PI-COF-2 with the value of 3.7 × 10-3 and 1.6 × 10-3 S m-1, respectively. Due to the same Co(II) electroactive sites together with similar permanent porosity and CO2 adsorption capacity for CoPc-PI-COFs, the cathodes made up of COFs and carbon black display a similar CO2-to-CO Faradaic efficiency of 87-97% at applied potentials between -0.60 and -0.90 V (vs RHE) in 0.5 M KHCO3 solution. However, in comparison with the CoPc-PI-COF-2&carbon black electrode, the CoPc-PI-COF-1 counterpart provides a larger current density (jCO) of -21.2 mA cm-2 at -0.90 V associated with its higher conductivity. This cathode also has a high turnover number and turnover frequency, amounting to 277 000 and 2.2 s-1 at -0.70 V during 40 h of measurement. The present result clearly discloses the great potential of 2D porous crystalline solids in electrocatalysis.

18.
Pak J Med Sci ; 37(5): 1408-1413, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34475921

RESUMEN

OBJECTIVE: To explore the effect of oxycodone hydrochloride combined with dexmedetomidine on the recovery quality and stress response during anesthesia in patients undergoing laparoscopic cholecystectomy (LC). METHODS: Ninety patients who had LC in Cangzhou Hospital of Integrated TCM-WM of Hebei from December 2016 to December 2019 were selected and divided into dexmedetomidine group (DEX group), oxycodone hydrochloride group (Q group), dexmedetomidine + oxycodone hydrochloride group (DQ group) by a random number table method, with 30 cases in each group. At the time before anesthesia induction (T0), and immediately (T1), 1 min (T2), 10 min (T3) and 30 minutes (T4) after extubation, the general vital signs of three groups were observed, and plasma cortisol (COR), epinephrine (E), norepinephrine (NE) and blood glucose (GLU) were measured. The spontaneous respiration recovery time, wake-up time, VAS score of each time period after extubation, extubation quality score, and adverse event rate were recorded. RESULTS: The vital signs at each time point of extubation, recovery time of spontaneous respiration, wake-up time, and extubation quality of DQ group were better than those of DEX group and Q group (P<0.05). The incidence of agitation, VAS score at T2 and T3, plasma concentrations of Cor, E, NE and Glu at T1, T3 and T4 in DQ group were significantly lower than those in Q group and DEX group (P<0.05). CONCLUSION: Oxycodone hydrochloride combined with dexmedetomidine can improve the recovery quality and reduce stress response in patients with LC after anesthesia, and can be safely used in patients with LC.

19.
Ecotoxicology ; 29(5): 584-593, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32468518

RESUMEN

Bifenthrin (BF) and acetochlor (AT) are widely used as an insecticide and herbicide, respectively, which are introduced to the aquatic environment as a natural result. Although the thyroid active substances may coexist in the environment, their joint effects on fish have not been identified. We examined the joint toxicity of BF and AT in zebrafish (Danio rerio) in this study. An acute lethal toxicity test indicated that the median lethal concentration (LC50) values of BF and AT under 96 h treatment were 0.40 and 4.56 µmol L-1, respectively. The binary mixture of BF + AT displayed an antagonistic effect on the acute lethal toxicity. After 14 days post fertilization (dpf) with exposure to individual pesticides at sub-lethal concentrations of, no effects were observed on the catalase (CAT) and peroxidase (POD) activities, while the binary mixtures (except for the 7.2 × 10-3 µmol L-1 BF + 1.2 × 10-2 µmol L-1 AT exposure group) significantly induced the CAT activity. The superoxide dismutase (SOD) activity and triiodothyronine (T3) level were significantly increased in all exposure groups. The thyroxine (T4) level remained unchanged after exposure to individual pesticides, but significantly increased in the 7.2 × 10-3 µmol L-1 BF + 1.2 × 10-2 µmol L-1 AT group. The expressions of the genes Dio2, TRa, TSHß and CRH in the thyroid hormone (TH) axis were significantly up-regulated in the 7.2 × 10-3 µmol L-1 BF + 0.4 × 10-2 µmol L-1 AT group. Our data indicated that the binary mixture of BF + AT significantly altered the antioxidant enzyme activities and gene expressions in the hypothalamic-pituitary-thyroid (HPT) axis and changed the TH levels.


Asunto(s)
Herbicidas/toxicidad , Piretrinas/toxicidad , Hormonas Tiroideas/metabolismo , Toluidinas/toxicidad , Pez Cebra/fisiología , Animales , Embrión no Mamífero/efectos de los fármacos , Glándula Tiroides/efectos de los fármacos , Hormonas Tiroideas/genética , Pruebas de Toxicidad Aguda
20.
J Am Chem Soc ; 141(43): 17431-17440, 2019 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-31608638

RESUMEN

Fabricating ultrathin two-dimensional (2D) covalent organic framework (COF) nanosheets (NSs) in large scale and high yield still remains a great challenge. This limits the exploration of the unique functionalities and wide range of application potentials of such materials. Herein, we develop a scalable general bottom-up approach to facilely synthesize ultrathin (<2.1 nm) imine-based 2D COF NSs (including COF-366 NSs, COF-367 NSs, COF-367-Co NSs, TAPB-PDA COF NSs, and TAPB-BPDA COF NSs) in large scale (>100 mg) and high yield (>55%), via an imine-exchange synthesis strategy through adding large excess amounts of 2,4,6-trimethylbenzaldehyde into the reaction system under solvothermal conditions. Impressively, visualization of the periodic pore lattice for COF-367 NSs by a scanning tunneling microscope (STM) clearly discloses the ultrathin 2D COF nature. In particular, the ultrathin COF-367-Co NSs isolated are subject to the heterogeneous photocatalyst for CO2-to-CO conversion, showing excellent efficiency with a CO production rate as high as 10 162 µmol g-1 h-1 and a selectivity of ca. 78% in aqueous media under visible-light irradiation, far superior to corresponding bulk materials and comparable with the thus far reported state-of-the-art visible-light driven heterocatalysts.

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