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1.
RSC Adv ; 14(4): 2264-2276, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38213965

RESUMEN

Conventional cerium-based denitrification catalysts show good catalytic activity at moderate and high temperatures, but their denitrification performance may be decreased due to poisoning by SO2 in the flue gas. In this paper, V was introduced into Ce-La/TiO2 catalysts by a ball-milling method, and the effects of the V content on catalyst denitrification performance and SO2 resistance were investigated. Fourier-transform diffuse reflectance in situ infrared spectroscopy was used to examine the denitrification mechanism and evaluate the catalysts for surface acidity, redox characteristics, and SO2 adsorption. After introducing V, Brønsted acids played the dominant role in the catalytic reaction by increasing the number of acidic sites on the catalyst surface, adsorbing NH3 to participate in the reaction, and improving the sulfur resistance by inhibiting SO2 poisoning. The Ce3+ and O ratio on the catalyst surface were also enhanced by V doping, which reduced interactions between SO2 and the primary metal oxide active ingredients. The modified catalyst inhibited the formation of sulfate species on the catalyst surface and prevented the generation of additional nitrate species on the surface, which protected the main active sites. After V doping, the NH3-SCR reaction on the catalyst surface followed the Langmuir-Hinshelwood mechanism.

2.
J Org Chem ; 89(1): 565-575, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38115769

RESUMEN

An array of biologically interesting tri/difluoromethylated chromones and their heteroatom analogues were conveniently synthesized from the reaction of chromones and their heteroatom analogues with CF3SO2Na or HCF2SO2Na in the presence of tert-butyl hydroperoxide under mild conditions. A mechanistic pathway involving the generation of the electrophilic tri/difluoromethyl radical, followed with the radical substitution of chromones and their heteroatom analogues, was postulated.

3.
Front Plant Sci ; 14: 1281373, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38053762

RESUMEN

Tobacco black shank induced by Phytophthora nicotianae causes significant yield losses in tobacco plants. MicroRNAs (miRNAs) play a pivotal role in plant biotic stress responses and have great potential in tobacco breeding for disease resistance. However, the roles of miRNAs in tobacco plants in response to P. nicotianae infection has not been well characterized. In this study, we found that Nta-miR6155, a miRNA specific to Solanaceae crops, was significantly induced in P. nicotianae infected tobacco. Some of predicted target genes of Nta-miR6155 were also observed to be involved in disease resistance. To further investigate the function of miR6155 in tobacco during P. nicotianae infection, Nta-miR6155 overexpression plants (miR6155-OE) were generated in the Honghua Dajinyuan tobacco variety (HD, the main cultivated tobacco variety in China). We found that the Nta-miR6155 overexpression enhanced the resistance in tobacco towards P. nicotianae infections. The level of reactive oxygen species (ROS) was significantly lower and antioxidant enzyme activities were significantly higher in miR6155-OE plants than those in control HD plants during P. nicotianae infection. In addition, we found that the accumulation of salicylic acid and the expression of salicylic acid biosynthesis and signal transduction-related genes is significantly higher in miR6155-OE plants in comparison to the control HD plants. Furthermore, we found that Nta-miR6155 cleaved target genes NtCIPK18 to modulate resistance towards P. nicotianae in tobacco plants. Additionally, phenotypic analysis of miR6155-OE plants showed that Nta-miR6155 could inhibit the growth of tobacco by suppressing nitrogen uptake and photosynthesis. In conclusion, our findings indicated that miR6155 plays a crucial role in the regulation of growth and resistance against P. nicotianae infections in tobacco plants.

4.
J Org Chem ; 88(15): 11083-11095, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37450647

RESUMEN

A metal-free synthesis of a series of fluoroalkyl-containing oxazoles from ß-monosubstituted enamines was developed. This fluoroacyloxylation/cyclization cascade process was mediated by fluoroalkyl-containing hypervalent iodine(III) species formed in situ from the reaction of phenyliodine(III) diacetate (PIDA) and RCF2CO2H (R = H, Cl, Br, F, CF3, CH3, Ph, SAr, OAr).

5.
BMC Public Health ; 23(1): 877, 2023 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-37173657

RESUMEN

BACKGROUND: As populations age, cancer burden becomes increasingly conspicuous. This study quantified the cancer burden of the elderly (≥ 60 years) in China, based on the China Cancer Registry Annual Report to provide epidemiological evidence for cancer prevention and control. METHODS: Data on cancer cases and deaths among the elderly aged ≥ 60 years were collected from the China Cancer Registry Annual Report, 2008-2019. Potential years of life lost (PYLL) and disability-adjusted life years (DALY) were calculated to analyze fatalities and the non-fatal burden. The time trend was analyzed using the Joinpoint model. RESULTS: From 2005 to 2016, the PYLL rate of cancer in the elderly was stable between 45.34‰ and 47.62‰, but the DALY rate for cancer decreased at an average annual rate of 1.18% (95% CI: 0.84-1.52%). The non-fatal cancer burden in the rural elderly was higher than that of the urban elderly. Lung, gastric, liver, esophageal, and colorectal cancers were the main cancers causing the cancer burden in the elderly, and accounted for 74.3% of DALYs. The DALY rate of lung cancer in females in the 60-64 age group increased (annual percentage change [APC] = 1.14%, 95% CI: 0.10-1.82%). Female breast cancer was one of the top five cancers in the 60-64 age group, with DALY rates that also increased (APC = 2.17%, 95% CI: 1.35-3.01%). With increasing age, the burden of liver cancer decreased, while that of colorectal cancer rose. CONCLUSIONS: From 2005 to 2016, the cancer burden in the elderly in China decreased, mainly reflected in the non-fatal burden. Female breast and liver cancer were a more serious burden in the younger elderly, while colorectal cancer burden was mainly observed in the older elderly.


Asunto(s)
Neoplasias de la Mama , Neoplasias Colorrectales , Neoplasias Hepáticas , Anciano , Humanos , Femenino , Persona de Mediana Edad , China/epidemiología , Sistema de Registros , Neoplasias Colorrectales/epidemiología , Años de Vida Ajustados por Calidad de Vida
6.
J Cell Mol Med ; 27(11): 1465-1476, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37078407

RESUMEN

There is a growing body of evidence that innate immunity also plays an important role in the progression of hepatitis B virus (HBV) infection. However, there is less study on systematically elucidating the characteristics of innate immunity in HBV-infected pregnant women. We compared the features of peripheral blood mononuclear cells in three healthy pregnant women and three HBV-infected pregnant women by single-cell RNA sequencing. 10 DEGs were detected between groups and monocytes were the main expression source of most of the DEGs, which involved in the inflammatory response, apoptosis and immune regulation. Meanwhile, qPCR and ELISA were performed to verify above genes. Monocytes displayed immune response defect, reflecting poor ability of response to IFN. In addition, eight clusters were identified in monocytes. We identified molecular drivers in monocytes subpopulations.TNFSF10+ monocytes, MT1G+ monocytes and TUBB1+ monocytes were featured with different gene expression pattern and biological function.TNFSF10+ monocytes and MT1G+ monocytes were characterized by high levels of inflammation response.TNFSF10+ monocytes, MT1G+ monocytes and TUBB1+ monocytes showed decreased response to IFN. Our results dissects alterations in monocytes related to the immune response of HBV-infected pregnant women and provides a rich resource for fully understanding immunopathogenesis and developing effective preventing HBV intrauterine infection strategies.


Asunto(s)
Hepatitis B , Complicaciones Infecciosas del Embarazo , Humanos , Embarazo , Femenino , Virus de la Hepatitis B/genética , Monocitos , Mujeres Embarazadas , Leucocitos Mononucleares/metabolismo , Antígenos de Superficie de la Hepatitis B , Complicaciones Infecciosas del Embarazo/genética , Hepatitis B/genética , Hepatitis B/metabolismo , Análisis de Secuencia de ARN
7.
Vet Microbiol ; 278: 109663, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36680971

RESUMEN

Coinfection of Porcine circovirus type 2 (PCV2) and Glaesserella parasuis type 4 (GPS4) is widespread clinically, resulting in high morbidity and mortality, however, interactions between the two pathogens during coinfection and the coinfection pathogenesis are poorly understood. In this study, a piglet model coinfected with PCV2 and GPS4 was established; coinfection of the piglets' group showed more obvious symptoms, such as high fever and emaciation, and more severe histological lesions appeared in various organs. Importantly, piglets in the coinfection group produced lower levels of PCV2 and GPS4 antibodies, and showed high levels of inflammatory cytokines, TLR2, and TLR4, while the levels of CD4, CD8, MHC II, costimulatory molecules, and IL-12p40 were decreased. In addition, a model of macrophage 3D4/21 cells coinfection with PCV2 and GPS4 was established, coinfected cells exhibited increased expression of the cytokines IL-6, IL-8, TNF-α, IL-1ß, and the receptors TLR2, TLR4, while decreased MHC II. We further demonstrate that cytokine production is associated with the activation of NF-κB and NLRP3 inflammasome signaling pathways, and TLR4 is also involved. Altogether, our findings suggest that coinfection with PCV2 and GPS4 exacerbates the inflammatory response, resulting in severe tissue damage, and probably impaired macrophage antigen presentation and T cell activation, resulting in immune dysregulation, aggravating host infection.


Asunto(s)
Infecciones por Circoviridae , Circovirus , Coinfección , Enfermedades de los Porcinos , Animales , Porcinos , Infecciones por Circoviridae/complicaciones , Infecciones por Circoviridae/veterinaria , Coinfección/veterinaria , Virulencia , Serogrupo , Receptor Toll-Like 2 , Receptor Toll-Like 4 , Citocinas
8.
Nucleic Acids Res ; 51(D1): D870-D876, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36300619

RESUMEN

CellMarker 2.0 (http://bio-bigdata.hrbmu.edu.cn/CellMarker or http://117.50.127.228/CellMarker/) is an updated database that provides a manually curated collection of experimentally supported markers of various cell types in different tissues of human and mouse. In addition, web tools for analyzing single cell sequencing data are described. We have updated CellMarker 2.0 with more data and several new features, including (i) Appending 36 300 tissue-cell type-maker entries, 474 tissues, 1901 cell types and 4566 markers over the previous version. The current release recruits 26 915 cell markers, 2578 cell types and 656 tissues, resulting in a total of 83 361 tissue-cell type-maker entries. (ii) There is new marker information from 48 sequencing technology sources, including 10X Chromium, Smart-Seq2 and Drop-seq, etc. (iii) Adding 29 types of cell markers, including protein-coding gene lncRNA and processed pseudogene, etc. Additionally, six flexible web tools, including cell annotation, cell clustering, cell malignancy, cell differentiation, cell feature and cell communication, were developed to analysis and visualization of single cell sequencing data. CellMarker 2.0 is a valuable resource for exploring markers of various cell types in different tissues of human and mouse.


Asunto(s)
Células , Bases de Datos Genéticas , Análisis de Expresión Génica de una Sola Célula , Animales , Humanos , Ratones , Bases de Datos de Ácidos Nucleicos , Neoplasias/genética , Análisis de Secuencia , Células/citología
9.
Front Public Health ; 10: 1023276, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36330120

RESUMEN

Background: To study the corresponding strategies for controlling cancer in older adults aged 60 and above in China, a comprehensive assessment of disease burden is required. Therefore, we will introduce the cancer epidemiological characteristics of older adults in China over a recent 12 year period. Methods: The age-period-cohort model was constructed using the cancer incidence data from the Chinese Cancer Registry Annual Report published in 2008-2019. The annual change percentage (APC) was estimated by log-linear regression to reflect the time trend. The data from the GLOBOCAN 2020 database was selected for worldwide comparative analysis. Results: The cancer incidence in older adults aged 60 and above in China showed a decreasing trend (APC = -0.73%, P = 0.009). The urban/rural ratio of cancer incidence increased from 0.94 to 1.07 (t = 3.52, P < 0.05), while the sex ratio (male/female) showed a significant decreasing trend only in rural areas (t = -6.77, P < 0.05), and the ratio decreased from 2.02 to 1.72. The results of the age-period-cohort model showed that the cancer incidence increased with age in both males and females, urban and rural areas. The RR of period effect increased from 2005 to 2010, then decreased from 2010 to 2015, and the downward trend was more obvious. The RR of the later-born cohort was lower than that of the earlier-born cohort in rural areas. Lung, gastric, colorectal, esophageal, liver, and breast cancers were common cancers in Chinese older adults. Lung cancer incidence ranked first in males, and it decreased with time in the 75-79 and 80-84 age groups (APC75 - 79 = -1.10%, APC80 - 84 = -0.88%, all P < 0.05). Breast cancer incidence ranked first among female in the 60-64 age group and showed an increasing trend (APC60 - 64 = 1.52%, P < 0.05). Conclusions: The cancer incidence in Chinese older adults aged 60 and above showed a decreasing trend, but it was still at a relatively high level. The key targets of prevention and treatment should be males, urban areas, younger people, older adults aged 60-69, lung, gastrointestinal, and breast cancers in the future.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Masculino , Anciano , Persona de Mediana Edad , Incidencia , Modelos Lineales , China/epidemiología , Estudios de Cohortes
10.
ACS Appl Mater Interfaces ; 14(46): 52402-52410, 2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36256442

RESUMEN

Artificial intelligence (AI) has become increasingly popular along with the development of the bionic neural system. Ionic conductors play an important role in the AI system due to the ability of bionic sensing and signal transporting. Traditional low-polarity elastomers possess outstanding mechanical strength and stability, such as polyurethane, which is difficult to be directly endowed with ionic conductivity without impairing its properties. Herein, we have first put forward a new approach to synthesize a liquid-free ionic conductive polyurethane (CPU) through one-step copolymerization between a green deep eutectic solvent (DES) and a prepolymer of polyurethane. The as-prepared CPU can retain the native properties of the traditional polyurethane (PU) such as the homogeneous phase, ease of molding, high transparency (about 93.3%), and excellent mechanical properties. By introducing the DES as the covalent cross-linking agent and ionic conductor at the same time, the CPU also has fine ionic conductivity (3.78 × 10-5 S cm-1), environmental resistance like anti-freezing (-20 °C), and solvent resistance. Based on the excellent conductivity and mechanical strength, the flexible CPU can be applied as a sensing element in pressure sensors. The CPU-based sensor has presented long-term stability, high sensitivity, and wide-ranging response (0.17-3.28 MPa) to the applied pressure, which will be suitable for the industrial demands for practical applications.

11.
Org Lett ; 24(23): 4187-4191, 2022 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-35670516

RESUMEN

The construction of 2-amino-1,3-selenazole skeleton was realized via the PhICl2/KSeCN-enabled electrophilic selenocyanation of ß-enaminones and ß-enamino esters followed by intramolecular cyclization under basic conditions. Compared to the classical Hantzsch strategy that utilizes selenourea or its analogues as starting materials or crucial intermediates, this method might represent an alternative approach for the assembly of 1,3-selenazole framework through a different pathway.


Asunto(s)
Ésteres , Esqueleto , Ciclización
12.
Ecol Evol ; 9(9): 5407-5419, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31110689

RESUMEN

BACKGROUND AND AIMS: Research into the variability of fine-root decomposition and nutrient cycling processes in arid and semiarid ecosystems is highly significant not only for investigations of regional and global carbon and nitrogen cycling but also for offering a theoretical basis for vegetation restoration and reconstruction. In particular, information is limited on fine-root decomposition processes and nutrient releasing characteristics in the high-altitude Qinghai Gonghe basin, which has different tree species and variable fine-root diameters. MATERIALS AND METHODS: Four types of Salicaceae and Caragana shrubs were selected at the Qinghai Gonghe desert ecosystem research station. The litterbag method was adopted to measure decomposition rates of fine-roots with three diameter classes (1-2 mm, 0.5-1 mm, and 0-0.5 mm). Chemical analysis was performed to determine nutrient (C, N, P, and K) concentrations of fine-root, and nutrient release rates were compared among fine-roots with different diameters during different decomposition periods. The differences in mass residual ratio and nutrient release rate among different diameter classes were studied with one-way ANOVA. RESULTS: Fine-root decomposition rates were in the order Caragana intermedia > Caragana korshinskii > Salix psammophila > Salix cheilophila. Fine-root decomposition showed a trend of "fast-slow-fast" variation, and decomposition rate increased as the diameter of fine-roots increased, irrespective of tree species. During the decomposition process, the nutrients C, N, and P of fine-root were in a release state for the four shrubs with different fine-root diameters, and the corresponding release rates of Caragana shrubs were higher than those of Salicaceae shrubs. Release rates of nutrients C and N accelerated as fine-root diameter increased, whereas release rates of nutrients P and K had no observed relation with fine-root diameter. Fine-root decomposition ratio was significantly correlated with initial values of N, P, C/N, C/P, and N/P of fine-root. Fine-root mass loss ratio was significantly correlated with initial concentration of soil nutrient K, and the correlation was positive for fine-roots with diameters of 0-0.5 mm and 0.5-1 mm; however, no other significant correlation was observed between fine-root mass loss ratio and initial soil environmental factors within this study. CONCLUSIONS: Our study showed that tree species and fine-root diameter strongly affected decomposition rates, whereas diameter class exerted little effect on nutrient release rates.

13.
Sci Rep ; 8(1): 12432, 2018 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-30127413

RESUMEN

Considering the variations in carbon concentrations among different plant components can significantly improve carbon storage estimates. The aim of this study was to estimate the biomass and carbon storage and sequestration in Caragana intermedia Kuang et H. C. Fu plantations for six different ages. The biomass and carbon sequestration in shrub biomass were quantified using a destructive method that involved analysing the carbon concentrations in the leaves, branches, stem bark, stem wood, roots > 5 mm, 2 mm < roots ≤ 5 mm, and roots ≤ 2 mm. The biomass and biomass carbon density of the C. intermedia plantations increased with the age of the stands. The biomass carbon density of the woody components was at its maximum in the 30-year-old plantation (14.27 ± 2.71 t·ha-1), indicating that C. intermedia plantations in alpine sandy land are an important carbon pool. The carbon accumulation rate of the woody components was higher during the early stages of plantation development. The carbon concentrations differed significantly among the components but changed only slightly with the stand age. The weighted mean carbon concentration of the woody components, which was found to be 44%, must be considered when estimating the long-term carbon pools in C. intermedia plantations.


Asunto(s)
Caragana/crecimiento & desarrollo , Caragana/fisiología , Secuestro de Carbono/fisiología , Carbono/metabolismo , Biomasa , China , Ecosistema , Suelo , Temperatura , Árboles/crecimiento & desarrollo , Árboles/fisiología
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