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1.
J Am Chem Soc ; 146(12): 8335-8342, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38487863

RESUMEN

The inherent inertness and striking physicochemical similarities of krypton and xenon pose significant challenges to their separation. Reported herein is the efficient xenon capture and xenon/krypton adsorptive separation by transition metal-free zeolites under ambient conditions. The polarized environment of zeolite, denoted as local polarity, can be tuned by changing the topology, framework composition, and counter-cations, which in turn correlates with the guest-host interaction and separation performance. Chabazite zeolite with a framework Si/Al ratio of 2.5 and Ca2+ as the counter-cations, namely, Ca-CHA-2.5, is developed as a state-of-the-art zeolite adsorbent, showing remarkable performance, i.e., high dynamic xenon uptake, high xenon/krypton separation selectivity, and good recyclability, in the adsorptive separation of the xenon/krypton mixture. Grand Canonical Monte Carlo simulation reveals that extraframework Ca2+ cations act as the primary binding sites for xenon and can stabilize xenon molecules together with the chabazite framework, whereas krypton molecules are stabilized by weak guest-host interaction with the zeolite framework.

2.
Small ; 20(16): e2308603, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38009482

RESUMEN

The shuttle effect of lithium polysulfides (LiPSs) severely hinders the development and commercialization of lithium-sulfur batteries, and the design of high-conductive carbon fiber-host material has become a key solution to suppress the shuttle effect. In this work, a unique Co/CoN-carbon nanocages@TiO2-carbon nanotubes structure (NC@TiO2-CNTs) is constructed using an electrospinning and nitriding process. Lithium-sulfur batteries using NC@TiO2-CNTs as cathode host materials exhibit high sulfur utilization (1527 mAh g-1 at 0.2 C) and can still maintain a discharge capacity of 663 mAh g-1 at a high current density of 5 C, and the capacity loss is only 0.056% per cycle during 500 cycles at 1 C. It is worth noting that even under extreme conditions (sulfur-loading = 90%, surface-loading = 5.0 mg cm-2 (S), and E/S = 6.63 µL mg-1), the lithium-sulfur batteries can still provide a reversible capacity of 4 mAh cm-2. Throughdensity functional theory calculations, it has been found that the Co/CoN heterostructures can adsorb and catalyze LiPSs conversion effectively. Simultaneously, the TiO2 can adsorb LiPSs and transfer Li+ selectively, achieving dual confinement for the shuttle effect of LiPSs (nanocages and nanotubes). The new findings provide a new performance enhancement strategy for the commercialization of lithium-sulfur batteries.

3.
Int J Obes (Lond) ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38926462

RESUMEN

BACKGROUND: The obesity paradox has been reported among older adults. However, whether the favorable effect of obesity is dependent on metabolic status remains largely unknown. We aimed to explore the association of metabolic obesity phenotypes and their changes with all-cause mortality among the Chinese oldest-old population. METHODS: This prospective cohort study included 1207 Chinese oldest old (mean age: 91.8 years). Metabolic obesity phenotypes were determined by central obesity and metabolic status, and participants were classified into metabolically healthy obesity (MHO), metabolically unhealthy obesity (MUO), metabolically healthy non-obesity (MHN), and metabolically unhealthy non-obesity (MUN). The hazard ratios (HRs) and 95% confidence intervals (95% CIs) were estimated by Cox regression models. RESULTS: During 5.3 years of follow-up, 640 deaths were documented. Compared with non-obesity, obesity was associated with a decreased mortality risk among participants with metabolically healthy (HR, 0.75; 95% CI, 0.63-0.91) while this association was insignificant among metabolically unhealthy. Compared to MHO, MHN (HR, 1.27; 95% CI, 1.06-1.53) and MUN (HR, 1.49; 95% CI, 1.10-2.02) were significantly associated with an increased mortality risk. Compared to those with stable MHO, those transited from MHO to MUO demonstrated a higher mortality risk (HR, 1.81; 95% CI, 1.06-3.11). CONCLUSIONS: MHO predicts better survival among the Chinese oldest-old population. These findings suggest that ensuring optimal management of metabolic health is beneficial and taking caution in weight loss based on the individual body weight for the metabolically healthy oldest-old adults.

4.
Inorg Chem ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38957956

RESUMEN

The separation of high-octane dibranched alkanes from naphtha is critical in the refining of gasoline. To date, research on the membrane-based separation of alkane isomers has been limited, with a particular paucity of investigations into mixed-matrix membranes. Herein, the continuous and dense UiO-66/PIM-1 mixed-matrix membrane, which was prepared through precise control of the interfacial structure, was first applied to the differentiation of C6 alkane isomers. Due to the synergistic combination of UiO-66 with differential adsorption capabilities for alkanes and PIM-1 that possesses a cross-linkable structure, the resulting UiO-66/PIM-1-(20) membrane demonstrated remarkable separation performance and high stability. Pervaporation measurements showed that the mass fraction of 2,2-dimethylbutane in the feed side was increased from 50.0 to 75.8 wt % while an excellent flux of 1700 g m-2 h-1 was maintained over a continuous 40 h period. The UiO-66/PIM-1-(20) membrane, characterized by its facile replication and processing, shows potential for large-scale fabrication. This study offers a new approach to the membrane separation of alkane isomers.

5.
Philos Trans A Math Phys Eng Sci ; 382(2271): 20230094, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38522461

RESUMEN

At the Royal Society meeting in 2023, we have mainly presented our lunar orbit array concept called DSL, and also briefly introduced a concept of a lunar surface array, LARAF. As the DSL concept had been presented before, in this article, we introduce the LARAF. We propose to build an array in the far side of the Moon, with a master station which handles the data collection and processing, and 20 stations with maximum baseline of 10 km. Each station consists of 12 membrane antenna units, and the stations are connected to the master station by power line and optical fibre. The array will make interferometric observation in the 0.1-50 MHz band during the lunar night, powered by regenerated fuel cells. The whole array can be carried to the lunar surface with a heavy rocket mission, and deployed with a rover in eight months. Such an array would be an important step in the long-term development of lunar-based ultralong wavelength radio astronomy. It has a sufficiently high sensitivity to observe many radio sources in the sky, though still short of the dark age fluctuations. We discuss the possible options in the power supply, data communication, deployment etc. This article is part of a discussion meeting issue 'Astronomy from the Moon: the next decades (part 2)'.

6.
Alzheimers Dement ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38946708

RESUMEN

INTRODUCTION: The study aimed to investigate the associations of changes in social isolation, loneliness, or both, with cognitive function. METHODS: Data were from 7299 older adults in the Chinese Longitudinal Healthy Longevity Survey. We defined four change patterns (no, incident, transient, and persistent) for social isolation and loneliness, and created nine-category variable to represent the joint changes. Tobit regression models and Cox models were performed. RESULTS: Incident, transient, and persistent social isolation or loneliness may accelerate cognitive decline (p < 0.05). Incident, transient, and persistent social isolation were associated with higher cognitive impairment risk, while only persistent loneliness was associated with higher cognitive impairment risk (p < 0.001). Notably, short-term or persistent social isolation was associated with accelerated cognitive decline and incident cognitive impairment, regardless of different loneliness change status (p < 0.05). DISCUSSION: Short-term or persistent social isolation and persistent loneliness may be a salient risk factor for cognitive decline and cognitive impairment. HIGHLIGHTS: Incident, transient, and persistent social isolation were associated with accelerated cognitive decline and higher cognitive impairment risk. Persistent loneliness was associated with accelerated cognitive decline and higher cognitive impairment risk. Short-term or persistent social isolation with concurrent different loneliness change status accelerated cognitive decline and higher cognitive impairment risk.

7.
Zhongguo Zhong Yao Za Zhi ; 48(12): 3207-3214, 2023 Jun.
Artículo en Zh | MEDLINE | ID: mdl-37382004

RESUMEN

The present study aimed to investigate the protective role of Shaofu Zhuyu Decoction(SFZY) against endometriosis fibrosis in mice, and decipher the underlying mechanism through the phosphatase and tensin homolog deleted on chromosome ten(PTEN)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR) pathway. Eighty-five BALB/c female mice were randomly assigned into a blank group, a model group, high-, medium, and low-dose SFZY(SFZY-H, SFZY-M, and SFZY-L, respectively) groups, and a gestrinone suspension(YT) group. The model of endometriosis was induced by intraperitoneal injection of uterine fragments. The mice in different groups were administrated with corresponding groups by gavage 14 days after modeling, and the blank group and model group with equal volume of distilled water by gavage. The treatment lasted for 14 days. The body weight, paw withdrawal latency caused by heat stimuli, and total weight of dissected ectopic focus were compared between different groups. The pathological changes of the ectopic tissue were observed via hematoxylin-eosin(HE) and Masson staining. Real-time PCR was employed to measure the mRNA levels of α-smooth muscle actin(α-SMA) and collagen type Ⅰ(collagen-Ⅰ) in the ectopic tissue. The protein levels of PTEN, Akt, mTOR, p-Akt, and p-mTOR in the ectopic tissue were determined by Western blot. Compared with the blank group, the modeling first decreased and then increased the body weight of mice, increased the total weight of ectopic focus, and shortened the paw withdrawal latency. Compared with the model group, SFZY and YT increased the body weight, prolonged the paw withdrawal latency, and decreased the weight of ectopic focus. Furthermore, the drug administration, especially SFZY-H and YT(P<0.01), recovered the pathological and reduced the area of collagen deposition. Compared with the blank group, the modeling up-regulated the mRNA levels of α-SMA and collagen-Ⅰ in the ectopic focus, and such up-regulation was attenuated after drug intervention, especially in the SFZY-H and YT groups(P<0.05,P<0.01). Compared with the blank group, the modeling down-regulated the protein level of PTEN and up-regulated the protein levels of Akt, mTOR, p-Akt, and p-mTOR(P<0.01, P<0.001). Drug administration, especially SFZY-H and YT, restored such changes(P<0.01). SFZY may significantly attenuate the focal fibrosis in the mouse model of endometriosis by regulating the PTEN/Akt/mTOR signaling pathway.


Asunto(s)
Coristoma , Endometriosis , Femenino , Animales , Ratones , Humanos , Proteínas Proto-Oncogénicas c-akt/genética , Endometriosis/tratamiento farmacológico , Endometriosis/genética , Serina-Treonina Quinasas TOR/genética , ARN Mensajero , Transducción de Señal , Peso Corporal , Mamíferos , Fosfohidrolasa PTEN/genética
8.
Chemistry ; 28(50): e202201659, 2022 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-35726763

RESUMEN

The development of cost-effective sorbents for direct capture of trace CO2 (<1 %) from the atmosphere is an important and challenging task. Natural or commercial zeolites are promising sorbents, but their performance in adsorption of trace CO2 has been poorly explored to date. A systematic study on capture of trace CO2 by commercial faujasite zeolites reveals that the extra-framework cations play a key role on their performance. Under dry conditions, Ba-X displays high dynamic uptake of 1.79 and 0.69 mmol g-1 at CO2 concentrations of 10000 and 1000 ppm, respectively, and shows excellent recyclability in the temperature-swing adsorption processes. K-X exhibits perfect moisture resistance, and >95 % dry CO2 uptake can be preserved under relative humidity of 74 %. In situ solid-state NMR spectroscopy, synchrotron X-ray diffraction and neutron diffraction reveal two binding sites for CO2 in these zeolites, namely the basic framework oxygen atoms and the divalent alkaline earth metal ions. This study unlocks the potential of low-cost natural zeolites for applications in direct air capture.

9.
Exp Lung Res ; 48(2): 53-60, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35075953

RESUMEN

BACKGROUND: Excessive macrophage-mediated inflammation participates in the development of Staphylococcus aureus (S. aureus)-induced pneumonia. Checkpoint kinase 2 (Chek2) was screened out as macrophage-related infantile pneumonia gene after the differentially expressed analysis of RNAseq data derived from pam3CSK4 stimulated bone marrow-derived macrophages (BMDMs). METHODS: RAW264.7 macrophage cells were transfected with Chek2-specific gRNA, which were further overexpressed with wide-type Chek2 or Chek2 kinase activity mutant (Chek2 KD, D368N). At the same time, the relative protein and mRNA expression of inflammatory cytokines were determined. C57BL/6J WT mice were intranasally infected with S. aureus to induce S. aureus-induced pneumonia, which was treated with BML-277, an inhibitor of Chek2. The symptoms of pneumonia mice and inflammatory cytokines associated with the nuclear factor kappa B (NF-κB) signaling pathways were further examined. RESULTS: In vivo, BML-277 significantly promoted pneumonia symptoms, including mortality, lung infiltration of immune cells, and the abundance of lung pro-inflammatory cytokines. Mechanically, BML-277 did not affect BMDMs survival but up-regulated the mRNA expression of tumor necrosis factor (Tnf), nitric oxide synthase 2 (Nos2), interleukin (Il)23a, and the secretion of Tnf-α and Il-23a. At the same time, genetic complementation experiment testified that Chek2 KD did not inhibit NF-κB and relevant inflammatory cytokines expression. CONCLUSION: Chek2 functions through the kinase mechanism to down-regulate the NF-κB pathway in macrophages to alleviate S. aureus-induced pneumonia in mice.


Asunto(s)
FN-kappa B , Neumonía , Animales , Ratones , FN-kappa B/metabolismo , Staphylococcus aureus , Quinasa de Punto de Control 2/metabolismo , Ratones Endogámicos C57BL , Macrófagos/metabolismo , Citocinas/metabolismo , Neumonía/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Ciclo Celular , ARN Mensajero/metabolismo , Lipopolisacáridos/farmacología
10.
Acta Pharmacol Sin ; 43(1): 133-145, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33758354

RESUMEN

N-n-Butyl haloperidol iodide (F2) is a novel compound that has antiproliferative and antifibrogenic activities. In this study we investigated the therapeutic potential of F2 against liver fibrosis in mice and the underlying mechanisms. Two widely used mouse models of fibrosis was established in mice by injection of either carbon tetrachloride (CCl4) or thioacetamide (TAA). The mice received F2 (0.75, 1.5 or 3 mg·kg-1·d-1, ip) for 4 weeks of fibrosis induction. We showed that F2 administration dose-dependently ameliorated CCl4- or TAA-induced liver fibrosis, evidenced by significant decreases in collagen deposition and c-Jun, TGF-ß receptor II (TGFBR2), α-smooth muscle actin (α-SMA), and collagen I expression in the liver. In transforming growth factor beta 1 (TGF-ß1)-stimulated LX-2 cells (a human hepatic stellate cell line) and primary mouse hepatic stellate cells, treatment with F2 (0.1, 1, 10 µM) concentration-dependently inhibited the expression of α-SMA, and collagen I. In LX-2 cells, F2 inhibited TGF-ß/Smad signaling through reducing the levels of TGFBR2; pretreatment with LY2109761 (TGF-ß signaling inhibitor) or SP600125 (c-Jun signaling inhibitor) markedly inhibited TGF-ß1-induced induction of α-SMA and collagen I. Knockdown of c-Jun decreased TGF-ß signaling genes, including TGFBR2 levels. We revealed that c-Jun was bound to the TGFBR2 promoter, whereas F2 suppressed the binding of c-Jun to the TGFBR2 promoter to restrain TGF-ß signaling and inhibit α-SMA and collagen I upregulation. In conclusion, the therapeutic benefit of F2 against liver fibrosis results from inhibition of c-Jun expression to reduce TGFBR2 and concomitant reduction of the responsiveness of hepatic stellate cells to TGF-ß1. F2 may thus be a potentially new effective pharmacotherapy for human liver fibrosis.


Asunto(s)
Haloperidol/análogos & derivados , Células Estrelladas Hepáticas/efectos de los fármacos , Cirrosis Hepática/tratamiento farmacológico , Animales , Tetracloruro de Carbono/administración & dosificación , Relación Dosis-Respuesta a Droga , Haloperidol/administración & dosificación , Haloperidol/farmacología , Células Estrelladas Hepáticas/metabolismo , Inyecciones Intraperitoneales , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Relación Estructura-Actividad , Tioacetamida/administración & dosificación , Factor de Crecimiento Transformador beta1/antagonistas & inhibidores , Factor de Crecimiento Transformador beta1/metabolismo
11.
Opt Express ; 29(11): 17246-17257, 2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-34154270

RESUMEN

The coherent Doppler wind lidar (CDL) shows capability in precipitation detection. Retrieval of the raindrop size distribution (DSD) using CDL is still challenging work, as both accurate backscattering cross section at the working wavelength and reflectivity spectrum of raindrop are required. Firstly, the Mie theory and the vectorial complex ray model (VCRM) are applied to calculate backscattering cross section for small spheric raindrops and large oblate raindrops, respectively. Secondly, an iterative deconvolution method is proposed to separate the reflectivity spectrum of raindrop from the lidar power spectrum, which is a superposition of rain and aerosol components. An accompanying aerosol signal model considering the effect of temporal window, from the same height and time, is used to improve the accuracy and robustness of the iteration. In experiment, a co-located micro rain radar (MRR) is used for comparison. Good agreements are obtained despite tremendous differences in wavelength and scattering characteristics. As an example, at 600 m height, the R2 of linear fitting to the mean rain velocity and mean raindrop diameter between CDL and MRR are 0.96 and 0.93, respectively.

12.
Public Health Nutr ; 24(15): 5081-5089, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33634772

RESUMEN

OBJECTIVE: Previous studies have reported inverse associations between certain healthy lifestyle factors and non-alcoholic fatty liver disease (NAFLD), but limited evidence showed the synergistic effect of those lifestyles. This study examined the relationship of a combination of lifestyles, expressed as Healthy Lifestyle Score (HLS), with NAFLD. DESIGN: A community-based cross-sectional study. Questionnaires and body assessments were used to collect data on the six-item HLS (ranging from 0 to 6, where higher scores indicate better health). The HLS consists of non-smoking (no active or passive smoking), normal BMI (18·5-23·9 kg/m2), physical activity (moderate or vigorous physical activity ≥ 150 min/week), healthy diet pattern, good sleep (no insomnia or <6 months) and no anxiety (Self-rating Anxiety Scale < 50), one point each. NAFLD was diagnosed by ultrasonography. SETTING: Guangzhou, China. PARTICIPANTS: Two thousand nine hundred and eighty-one participants aged 40-75 years. RESULTS: The overall prevalence of NAFLD was 50·8 %. After adjusting for potential covariates, HLS was associated with lower presence of NAFLD. The OR of NAFLD for subjects with higher HLS (3, 4, 5-6 v. 0-1 points) were 0·68 (95 % CI 0·51, 0·91), 0·58 (95 % CI 0·43, 0·78) and 0·35 (95 % CI 0·25, 0·51), respectively (P-values < 0·05). Among the six items, BMI and physical activity were the strongest contributors. Sensitivity analyses showed that the association was more significant after weighting the HLS. The beneficial association remained after excluding any one of the six components or replacing BMI with waist circumference. CONCLUSIONS: Higher HLS was associated with lower presence of NAFLD, suggesting that a healthy lifestyle pattern might be beneficial to liver health.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Adulto , Anciano , China/epidemiología , Estudios Transversales , Estilo de Vida Saludable , Humanos , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Factores de Riesgo , Circunferencia de la Cintura
13.
Ann Rheum Dis ; 79(6): 829-836, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32253185

RESUMEN

OBJECTIVES: To evaluate the associations of regular glucosamine use with all-cause and cause-specific mortality in a large prospective cohort. METHODS: This population-based prospective cohort study included 495 077 women and men (mean (SD) age, 56.6 (8.1) years) from the UK Biobank study. Participants were recruited from 2006 to 2010 and were followed up through 2018. We evaluated all-cause mortality and mortality due to cardiovascular disease (CVD), cancer, respiratory and digestive disease. HRs and 95% CIs for all-cause and cause-specific mortality were calculated using Cox proportional hazards models with adjustment for potential confounding variables. RESULTS: At baseline, 19.1% of the participants reported regular use of glucosamine supplements. During a median follow-up of 8.9 years (IQR 8.3-9.7 years), 19 882 all-cause deaths were recorded, including 3802 CVD deaths, 8090 cancer deaths, 3380 respiratory disease deaths and 1061 digestive disease deaths. In multivariable adjusted analyses, the HRs associated with glucosamine use were 0.85 (95% CI 0.82 to 0.89) for all-cause mortality, 0.82 (95% CI 0.74 to 0.90) for CVD mortality, 0.94 (95% CI 0.88 to 0.99) for cancer mortality, 0.73 (95% CI 0.66 to 0.81) for respiratory mortality and 0.74 (95% CI 0.62 to 0.90) for digestive mortality. The inverse associations of glucosamine use with all-cause mortality seemed to be somewhat stronger among current than non-current smokers (p for interaction=0.00080). CONCLUSIONS: Regular glucosamine supplementation was associated with lower mortality due to all causes, cancer, CVD, respiratory and digestive diseases.


Asunto(s)
Enfermedades Cardiovasculares/mortalidad , Enfermedades del Sistema Digestivo/mortalidad , Glucosamina/uso terapéutico , Neoplasias/mortalidad , Enfermedades Respiratorias/mortalidad , Suplementos Dietéticos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mortalidad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Reino Unido/epidemiología
14.
Opt Express ; 28(25): 37406-37418, 2020 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-33379576

RESUMEN

Researches on the atmospheric boundary layer (ABL) need accurate measurements with high temporal and spatial resolutions from a series of different instruments. Here, a method for identifying cloud, precipitation, windshear, and turbulence in the ABL using a single coherent Doppler wind lidar (CDWL) is proposed and demonstrated. Based on deep analysis of the power spectrum of the backscattering signal, multiple lidar products, such as carrier-to-noise (CNR), spectrum width, spectrum skewness, turbulent kinetic energy dissipation rate (TKEDR), and shear intensity are derived for weather identification. Firstly, the cloud is extracted by Haar wavelet covariance transform (HWCT) algorithm based on the CNR after range correction. Secondly, since the spectrum broadening may be due to turbulence, windshear or precipitation, the spectrum skewness is introduced to distinguish the precipitation from two other conditions. Whereas wind velocity is obtained by single peak fitting in clear weather condition, the double-peak fitting is used to retrieve wind and rainfall velocities simultaneously in the precipitation condition. Thirdly, judging from shear intensity and TKEDR, turbulence and windshear are classified. As a double check, the temporal continuity is used. Stable wind variances conditions such as low-level jets are identified as windshear, while arbitrary wind variances conditions are categorized as turbulence. In the field experiment, the method is implemented on a micro-pulse CDWL to provide meteorological services for the 70th anniversary of the China's National Day, in Inner Mongolia, China (43°54'N, 115°58'E). All weather conditions are successfully classified. By comparing lidar results to that of microwave radiometer (MWR), the spectrum skewness is found be more accurate to indicate precipitation than spectrum width or vertical speed. Finally, the parameter relationships and distributions are analyzed statistically in different weather conditions.

15.
Respir Res ; 21(1): 144, 2020 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-32522221

RESUMEN

Acute lung injury (ALI) is a highly lethal pulmonary disease that causes edema, hypoxemia and respiratory failure. Recent evidence indicates that nuclear factor-kappa B (NF-κB) plays a crucial role in ALI development. However, the regulatory mechanism of NF-κB on ALI remains enigmatic. In this study, we investigated potential molecular mechanism of NF-κB on ALI induced by lipopolysaccharide (LPS). BALB/c mice were subjected to intratracheal spraying of LPS to generate an ALI mode, with the activity of NF-κB in mice tissues being detected by enzyme linked immunosorbent assay (ELISA), and the number of inflammatory cells in bronchoalveolar lavage fluid being counted. Then, the macrophage cell line RAW264.7 exposed to LPS were treated with ammonium pyrrolidinedithiocarbamate (PDTC) (inhibitor of NF-κB), miR-194 mimic, or oe-chemokine receptor type 4 (CXCR4) separately or in combination. After that, ELISA and reverse transcription quantitative polymerase chain reaction (RT-qPCR) were used to detect the expression level of IL-1ß, IL-6, TNF-α, miR-194 and CXCR4, respectively. In addition, the targeting relationship between miR-194 and CXCR4 was verified by dual-luciferase reporter gene assay. The dry/wet ratio of lung and the MPO activity were also measured to assess the inflammatory response in mice. Activation of NF-κB down-regulated the miR-194 expression in LPS-induced ALI. Overexpression of miR-194 alleviated LPS-induced ALI and reduced the expression of inflammatory factors IL-1ß, IL-6 and TNF-α via targeting CXCR4. In LPS-induced ALI, NF-κB mediates the CXCR4 expression by inhibiting the expression of miR-194, thus promoting the inflammatory injury of lung.


Asunto(s)
Lesión Pulmonar Aguda/genética , Regulación hacia Abajo , Regulación de la Expresión Génica , MicroARNs/genética , FN-kappa B/genética , Lesión Pulmonar Aguda/metabolismo , Lesión Pulmonar Aguda/patología , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Femenino , Ratones , Ratones Endogámicos BALB C , MicroARNs/biosíntesis , FN-kappa B/biosíntesis , Transducción de Señal
16.
BMC Geriatr ; 20(1): 29, 2020 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-31992221

RESUMEN

BACKGROUND: Cognitive impairment is a major contributor to mortality among the elderly. However, the relationship between cognitive impairment evaluated by educational levels and mortality and the trend between cognitive impairment and mortality with time are unclear. We aim to evaluate the differences in associations of cognitive impairment, taking the stratification by educational levels into account, with all-cause mortality and further explore the relationship of cognitive impairment with mortality in different age and sex groups in two cohorts ascertained 6 years apart in China. METHODS: A total of 13,906 and 13,873 Chinese elderly aged 65 years and older were included in the 2002-2008 and 2008-2014 cohorts from the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Mortality data was ascertained from interviews with family members or relatives of participants. Cognitive function, evaluated by the Mini-Mental State Examination (MMSE), were defined by different cut-offs taking educational background into account. Cox models were used to explore the relationship of cognitive impairment with mortality. RESULTS: For the 2002-2008 and 2008-2014 cohorts, 55,277 and 53,267 person-years were followed up, and the mean (SD) age were 86.5 (11.6) and 87.2 (11.3) years, respectively. Compared to normal cognition, cognitive impairment was independently associated with higher mortality risk after controlling for potential confounders, with hazard ratios (HRs) of 1.32 (95% confidence interval [CI], 1.25-1.39) in 2002-2008 cohort and 1.26 (95% CI, 1.19-1.32) in 2008-2014 cohort, stratified by educational levels. The trend of cognitive impairment with all-cause mortality risk decreased from 2002 to 2008 to 2008-2014 cohort, while no significant interaction of cognitive impairment with cohort for all-cause mortality was observed. The associations of cognitive impairment and mortality were decreased with age in the two cohorts. CONCLUSIONS: Cognitive impairment evaluated by different cut-offs were associated with increased risk of mortality, especially among those aged 65-79 years in the two cohorts; this advocates that periodic screening for cognitive impairment among the elderly is warranted.


Asunto(s)
Disfunción Cognitiva/mortalidad , Disfunción Cognitiva/psicología , Pruebas de Estado Mental y Demencia , Anciano , Anciano de 80 o más Años , China/epidemiología , Cognición/fisiología , Disfunción Cognitiva/diagnóstico , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Longevidad/fisiología , Estudios Longitudinales , Masculino , Mortalidad/tendencias , Estudios Prospectivos , Factores de Tiempo
17.
Can Assoc Radiol J ; 71(1): 92-99, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32062994

RESUMEN

PURPOSE: To evaluate the efficacy of the semiquantitative and quantitative parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in differentiating between benign and malignant soft-tissue tumors. METHODS: A total of 45 patients with pathologically confirmed soft-tissue tumors (15 benign and 30 malignant tumors) underwent DCE-MRI. The semiquantitative parameters assessed were as follows: time to peak (TTP), maximum concentration (MAX Conc), area under the curve of time-concentration curve (AUC-TC), and maximum rise slope (MAX Slope). Quantitative DCE-MRI was analyzed with the extended Tofts-Kety model to assess the following quantitative parameters: volume transfer constant (Ktrans), microvascular permeability reflux constant (Kep), and distribute volume per unit tissue volume (Ve). Data were evaluated using the independent t test or Mann-Whitney U test and receiver operating characteristic (ROC) curves. RESULTS: The TTP (P = .0035), MAX Conc (P = .0018), AUC-TC (P = .0018), MAX Slope (P = .0018), Ktrans (P = .0018), and Kep (P = .0035) were significantly different between the benign and malignant soft-tissue tumors. The AUC of the ROC curve demonstrated the diagnostic potential of TTP (0.778), MAX Conc (0.849), AUC-TC (0.831), MAX Slope (0.847), Ktrans (0.836), Kep (0.778), and Ve (0.638). CONCLUSIONS: The use of semiquantitative and quantitative parameters of DCE-MRI enabled differentiation between benign and malignant soft-tissue tumors. The values of TTP were lower, while those of MAX Conc, AUC-TC, MAX Slope, Ktrans, and Kep were higher in malignant than in benign tumors.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Neoplasias de los Tejidos Blandos/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Diagnóstico Diferencial , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Neoplasias de los Tejidos Blandos/patología
18.
BMC Oral Health ; 20(1): 100, 2020 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-32276615

RESUMEN

BACKGROUND: The associations between the number of natural teeth/denture use and all-cause mortality remain unclear due to lake of investigation for the potential interaction between tooth loss and denture use and for the potential changes in these exposures over time in older adults. We undertake this study to evaluate the associations of the number of natural teeth and/or denture use with mortality in Chinese elderly. METHODS: This is a prospective cohort study of 36,283 older adults (median age: 90). The number of natural teeth and denture use were collected with structured questionnaire. We evaluated hazard ratios (HRs) and confidence intervals (CIs) using a Cox proportional hazards model adjusting for demographic factors, education, income, lifestyle factors, and comorbidities. RESULTS: We documented 25,857 deaths during 145,947 person-years of observation. Compared to those with 20+ teeth, tooth loss was associated with a gradual increase in mortality, with an adjusted HR of 1.14 (95% CI, 1.06 to 1.23) for those with 10-19 teeth, 1.23 (95% CI, 1.15 to 1.31) for those with 1-9 teeth, and 1.35 (95% CI, 1.26 to 1.44) for those without natural teeth. Denture use was associated with lower risk of mortality (adjusted HR 0.81; 95% CI, 0.77 to 0.84). Subgroup analyses indicated that the benefit of denture use was greater in men than in women (P = 0.02) and tended to decrease with age (P < 0.001). The effects of denture use did not differ among various degrees of tooth loss (P = 0.17). CONCLUSIONS: Tooth loss was associated with an increased risk of mortality in older adults. Denture use provided a protective effect against death for all degrees of tooth loss however, this effect appeared to be modified by sex and age.


Asunto(s)
Dentaduras/estadística & datos numéricos , Mortalidad , Boca Edéntula , Vigilancia de la Población/métodos , Pérdida de Diente/epidemiología , Anciano , Anciano de 80 o más Años , Pueblo Asiatico , Estudios de Cohortes , Femenino , Humanos , Masculino , Estudios Prospectivos , Factores de Riesgo
19.
Chemistry ; 25(65): 14771-14774, 2019 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-31529655

RESUMEN

Cuprous oxide microcrystals with {111}, {111}/{100}, and {100} exposed facets were synthesized. 31 P MAS NMR using trimethylphosphine as the probe molecule was employed to study the acidic properties of samples. It was found that the total acidic density of samples increases evidently after sulfation compared with the pristine cuprous oxide microcrystals. During sulfation, new {100} facets are formed at the expense of {111} facets and lead to the generation of two Lewis acid sites due to the different binding states of SO4 2- on {111} and {100} facets. Moreover, DFT calculation was used to illustrate the binding models of SO4 2- on {111} and {100} facets. Also, a Pechmann condensation reaction was applied to study the acidic catalytic activity of these samples. It was found that the sulfated {111} facet has better activity due to its higher Lewis acid density compared with the sulfated {100} facet.

20.
J Nutr ; 149(6): 1056-1064, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30949685

RESUMEN

BACKGROUND: High concentrations of plasma 25-hydroxyvitamin D [25(OH)D], a marker of circulating vitamin D, have been associated with a lower risk of mortality in epidemiologic studies of multiple populations, but the association for Chinese adults aged ≥80 y (oldest old) remains unclear. OBJECTIVE: We investigated the association between plasma [25(OH)D] concentration and all-cause mortality among Chinese adults aged ≥80 y. DESIGN: The present study is a prospective cohort study of 2185 Chinese older adults (median age: 93 y). Prospective all-cause mortality data were analyzed for survival in relation to plasma 25(OH)D using Cox proportional hazards regression models, with adjustments for potential sociodemographic and lifestyle confounders and biomarkers. The associations were measured with HR and 95% CIs. RESULTS: The median plasma 25(OH)D concentration was 34.4 nmol/L at baseline. Over the 5466 person-year follow-up period, 1100 deaths were identified. Men and women were analyzed together as no effect modification by sex was found. After adjusting for multiple potential confounders, the risk of all-cause mortality decreased as the plasma 25(OH)D concentration increased (P-trend <0.01). Compared with the lowest age-specific quartile of plasma 25(OH)D, the adjusted HRs for mortality for the second, third, and fourth age-specific quartiles were 0.72 (95% CI: 0.57, 0.90), 0.73 (95% CI: 0.58, 0.93), and 0.61 (95% CI: 0.47, 0.81), respectively. The observed associations were broadly consistent across age and other subgroups. Sensitivity analyses generated similar results after excluding participants who died within 2 y of follow-up or after further adjustment for ethnicity and chronic diseases. CONCLUSIONS: A higher plasma 25-hydroxyvitamin D concentration was associated with a reduced risk of all-cause mortality among Chinese adults aged ≥80 y. This observed inverse association warrants further investigation in randomized controlled trials testing vitamin D supplementation in this age group.


Asunto(s)
Mortalidad , Vitamina D/análogos & derivados , Factores de Edad , Anciano de 80 o más Años , Envejecimiento/sangre , Pueblo Asiatico/estadística & datos numéricos , Biomarcadores/sangre , China/epidemiología , Estudios de Cohortes , Femenino , Humanos , Longevidad/fisiología , Estudios Longitudinales , Masculino , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo , Vitamina D/sangre
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