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1.
IUBMB Life ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38838376

RESUMEN

Multiple sclerosis (MS) is a common autoimmune illness that is difficult to treat. The upregulation of Th17 cells is critical in the pathological process of MS. Hederagenol (Hed) has been shown to lower IL-17 levels, although its role in MS pathophysiology is uncertain. In this study, we explore whether Hed could ameliorate MS by modulating Th17 cell differentiation, with the goal of identifying new treatment targets for MS. The experimental autoimmune encephalomyelitis (EAE) mouse model was conducted and Hed was intraperitoneally injected into mice. The weight was recorded and the clinical symptom grade was assessed. Hematoxylin-eosin staining was carried out to determine the extent of inflammation in the spinal cord and liver. The luxol Fast Blue staining was performed to detect the pathological changes in the myelin sheath. Nerve damage was detected using NeuN immunofluorescence staining and terminal deoxynucleotidyl transferase dUTP nick-end labeling staining. Immunohistology approaches were used to study alterations in immune cells in the spinal cord. The proportions of T cell subsets in the spleens were analyzed by flow cytometry. RORγt levels were measured using quantitative real-time PCR or Western blot. The activity of the RORγt promoter was analyzed by Chromatin immunoprecipitation. Hed administration reduced the clinical symptom grade of EAE mice, as well as the inflammatory infiltration, demyelination, and cell disorder of the spinal cord, while having no discernible effect on the mouse weight. In addition, Hed treatment significantly reduced the number of T cells, particularly Th17 cells in the spinal cord and spleen-isolated CD4+ T cells. Hed lowered the RORγt levels in spleens and CD4+ T cells and overexpression of RORγt reversed the inhibitory effect of Hed on Th17 differentiation. Hed decreased nerve injury by modulating Th17 differentiation through the RORγt promoter. Hed regulates Th17 differentiation by reducing RORγt promoter activity, which reduces nerve injury and alleviates EAE.

2.
Acta Biochim Biophys Sin (Shanghai) ; 55(8): 1222-1233, 2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37431183

RESUMEN

The neuroprotective role of 5-hydroxymethyl-2-furfural (5-HMF) has been demonstrated in a variety of neurological diseases. The aim of this study is to investigate the effect of 5-HMF on multiple sclerosis (MS). IFN-γ-stimulated murine microglia (BV2 cells) are considered a cell model of MS. With 5-HMF treatment, microglial M1/2 polarization and cytokine levels are detected. The interaction of 5-HMF with migration inhibitory factor (MIF) is predicted using online databases. The experimental autoimmune encephalomyelitis (EAE) mouse model is established, followed by a 5-HMF injection. The results show that 5-HMF facilitates IFN-γ-stimulated microglial M2 polarization and attenuates the inflammatory response. According to the network pharmacology and molecular docking results, 5-HMF has a binding site for MIF. Further results show that blocking MIF activity or silencing CD74 enhances microglial M2 polarization, reduces inflammatory activity, and prevents ERK1/2 phosphorylation. 5-HMF inhibits the MIF-CD74 interaction by binding to MIF, thereby inhibiting microglial M1 polarization and enhancing the anti-inflammatory response. 5-HMF ameliorates EAE, inflammation, and demyelination in vivo. In conclusion, our research indicates that 5-HMF promotes microglial M2 polarization by inhibiting the MIF-CD74 interaction, thereby attenuating inflammation and demyelination in EAE mice.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Factores Inhibidores de la Migración de Macrófagos , Animales , Ratones , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Ratones Endogámicos C57BL , Microglía/metabolismo , Simulación del Acoplamiento Molecular
3.
J Environ Manage ; 232: 781-788, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30529865

RESUMEN

Subtropical forests function as important carbon sinks for atmospheric CO2. Nonetheless, there remain uncertainties about the effects of climate and topography on subtropical forest biomass-carbon stocks. A continuous biomass expansion factor (BEF) method was applied to forest inventory data to estimate biomass-carbon storage and carbon sink rate, and their changes along with abiotic and biotic factors in the Pearl River Delta (PRD) of South China. BEF equations were built using a set of field-based data. Biomass-carbon increased from 62.92 to 70.56 Mt along with forest growth and increasing forest area during the latest two periods of the national forest inventory (2004-8 and 2009-13). The PRD's forests continued to be net carbon sinks 0.51 t ha-1 yr-1. The PRD's forests have a high potential as biomass-carbon sinks in the future, because 46.75% of the forests are at the young or middle-aged stage. In addition, principal component analysis indicated that both biomass-carbon density and carbon sink rate were positively correlated with the area percentage of mature and over-mature forests, average annual precipitation and minimum temperature, but they were negatively correlated with average annual maximum temperature. Pearson correlation analysis demonstrated that biomass-carbon density and carbon sink rate affected by average altitude, while they were not related to the slope angle.


Asunto(s)
Carbono , Ríos , Biomasa , Secuestro de Carbono , China , Bosques , Árboles
4.
Phys Chem Chem Phys ; 19(7): 4956-4961, 2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-28155953

RESUMEN

The electron transport layer (ETL) plays a critical role in high efficiency perovskite solar cells. In this study, an anodic TiO2 nanotube film was transformed into a TiO2 nanotube network film, which maintained its advantage as an efficient ETL for perovskite solar cells. Compared with the mesoporous TiO2 nanoparticle ETL, the TiO2 nanotube network ETL can increase the efficiency of perovskite solar cells by 26.6%, which is attributed to its superior charge collection property and light trapping ability. The results confirm the importance of optimizing the electron collecting layer and suggest another way to design and fabricate novel perovskite solid state solar cells, potentially by using a TiO2 nanotube network film as an alternative high efficiency electrode.

5.
Phys Chem Chem Phys ; 18(6): 4643-51, 2016 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-26794602

RESUMEN

Band gap opening and modulating are critical in dictating the functionalities of single walled carbon nanotubes (SWCNTs) in a broad array of nano-devices. Using first-principles density functional theory calculations, a class of semiconducting armchair SWCNTs with a distinctive BN line defect are studied, showing a super capacity to open the band gap of (4, 4) SWCNT to as large as 0.86 eV, while the opened band gap are found decreasing with the increasing diameters of SWCNTs. The opened band gap of SWCNTs can also be successfully modulated through both mechanical and electrical approaches by applying compressive uniaxial strain and electric field. This study provides novel insights into the large band gap opening and modulating of SWCNTs and could be useful in facilitating future applications of SWCNTs in electronic, optical and thermoelectric devices.

6.
J Neurochem ; 134(3): 551-65, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25952107

RESUMEN

Hypoxia-mediated neurotoxicity contributes to various neurodegenerative disorders, including Alzheimer's disease and multiple sclerosis. Tetramethylpyrazine (TMP), a major bioactive component purified from Ligusticum wallichii Franchat, exhibited potent neuroprotective effect. However, the mechanism of TMP-exerted neuroprotective effect against hypoxia was not clear. In the study, we investigated the mechanism of the neuroprotective effect of TMP against hypoxia induced by CoCl2 in vitro and in vivo. The results showed that TMP could protect against CoCl2 -induced neurotoxicity in PC12 cells and in rats, as evidenced by enhancement of cell viability in PC12 cells and improvement of learning and memory ability in rats treated with CoCl2 . TMP could inhibit mitochondrial dysfunction, mitochondrial apoptotic molecular events, and thus apoptosis induced by CoCl2 . TMP inhibited CoCl2 -increased reactive oxygen species (ROS) level, which may contribute to hypoxia-related neurotoxicity induced by CoCl2 . The antioxidant and neuroprotective activities of TMP involved two pathways: one was the enhancement of nuclear factor erythroid 2-related factor 2 (Nrf2)/catalytic subunit of γ-glutamylcysteine ligase-mediated regulation of GSH and the other was the inhibition of hypoxia-inducible factor 1 α/NADPH oxidase 2 (NOX2)-mediated ROS generation. These two pathways contributed to improvement of oxidative stress and thus the amelioration of apoptosis under hypoxic conditions. These results have appointed a new path toward the understanding of pathogenesis and TMP-related therapy of hypoxia-related neurodegenerative diseases. We proposed two cascades for tetramethylpyrazine-exhibited protective effects against CoCl2 -induced neurotoxicity: One is enhancement of nuclear factor erythroid 2-related factor 2-catalytic subunit of γ-glutamylcysteine ligase-mediated regulation of glutathone and the other was the inhibition of hypoxia-inducible factor 1 α-NADPH oxidase-2-mediated ROS generation. We think these findings should provide a new understanding of pathogenesis and tetramethylpyrazine-related therapy of hypoxia-related neurodegenerative diseases.


Asunto(s)
Hipoxia de la Célula/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Pirazinas/farmacología , Transducción de Señal/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Western Blotting , Inmunoprecipitación de Cromatina , Cobalto/toxicidad , Glutamato-Cisteína Ligasa/metabolismo , Glutatión/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Masculino , Glicoproteínas de Membrana/metabolismo , NADPH Oxidasa 2 , NADPH Oxidasas/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Células PC12 , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Transfección
7.
J Nanosci Nanotechnol ; 14(6): 4541-50, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24738426

RESUMEN

Bamboo-type TiO2 nanotube arrays with high surface area can be synthesized by alternating voltage (AV) anodization for their important use as photocatalytic medium. Their morphologies are highly dependent on preparation parameters including anodization time and electrolyte composition. Minimum time of high-voltage steps required for forming desired bamboo ridge spacing on these nanotubes can be calculated from current-time profiles recorded during potentiostatic anodization at the voltage. Water content in NH4F-containing ethylene glycol (EG) electrolytes is optimized simply from analyses of current transients or current-voltage relations for anodization in EG electrolytes with different amount of water, in order to achieve efficient electrochemical growth of TiO2 nanotubes for large ridge density and long tube length. Two types of bamboo-type TiO2 nanotubes with the same length of 5.46 microm but different ridge spacing are synthesized for photocatalytic degradation of methylene blue (MB) under UV radiation. Both of the bamboo-type nanotube arrays show improved photo catalysis compared to smooth TiO2 nanotubes of the same length, due to their larger surface area favorable for heterogeneous catalytic processes. In particular, the apparent rate constant of photocatalytic degradation on bamboo-type nanotubes is up to 29.4% higher than that for degradation on smooth ones.


Asunto(s)
Azul de Metileno/química , Nanotubos/química , Sasa/ultraestructura , Titanio/química , Materiales Biomiméticos/síntesis química , Materiales Biomiméticos/química , Catálisis/efectos de la radiación , Luz , Ensayo de Materiales , Azul de Metileno/efectos de la radiación , Nanotubos/efectos de la radiación , Nanotubos/ultraestructura , Tamaño de la Partícula , Sasa/química
8.
World J Clin Cases ; 12(7): 1227-1234, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38524502

RESUMEN

BACKGROUND: Despite being one of the most prevalent sleep disorders, obstructive sleep apnea hypoventilation syndrome (OSAHS) has limited information on its immunologic foundation. The immunological underpinnings of certain major psychiatric diseases have been uncovered in recent years thanks to the extensive use of genome-wide association studies (GWAS) and genotyping techniques using high-density genetic markers (e.g., SNP or CNVs). But this tactic hasn't yet been applied to OSAHS. Using a Mendelian randomization analysis, we analyzed the causal link between immune cells and the illness in order to comprehend the immunological bases of OSAHS. AIM: To investigate the immune cells' association with OSAHS via genetic methods, guiding future clinical research. METHODS: A comprehensive two-sample mendelian randomization study was conducted to investigate the causal relationship between immune cell characteristics and OSAHS. Summary statistics for each immune cell feature were obtained from the GWAS catalog. Information on 731 immune cell properties, such as morphologic parameters, median fluorescence intensity, absolute cellular, and relative cellular, was compiled using publicly available genetic databases. The results' robustness, heterogeneity, and horizontal pleiotropy were confirmed using extensive sensitivity examination. RESULTS: Following false discovery rate (FDR) correction, no statistically significant effect of OSAHS on immunophenotypes was observed. However, two lymphocyte subsets were found to have a significant association with the risk of OSAHS: Basophil %CD33dim HLA DR- CD66b- (OR = 1.03, 95%CI = 1.01-1.03, P < 0.001); CD38 on IgD+ CD24- B cell (OR = 1.04, 95%CI = 1.02-1.04, P = 0.019). CONCLUSION: This study shows a strong link between immune cells and OSAHS through a gene approach, thus offering direction for potential future medical research.

9.
J Nanosci Nanotechnol ; 12(9): 7113-20, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23035441

RESUMEN

LiMn2O4 suffers from severe capacity degradation when used as a cathode material in rechargeable lithium-ion batteries, especially when cycled at high rates and elevated temperatures. To enhance its high-rate electrochemical performance at elevated temperature (55 degrees C), we use atomic layer deposition (ALD) to deposit ultrathin and highly conformal Al2O3 coatings (as thin as 0.72 nm) onto micron-sized and nano-sized LiMn2O4 with precise thickness-control at atomic scale. All ALD-modified electrodes exhibit significantly improved capacities and cycling stability compared to bare electrodes. In particular, the effect of ALD coating to improve electrochemical performance of LiMn2O4 is more distinct for nano-sized LiMn2O4 than for micron-sized LiMn2O4, and more distinct for electrochemical cycling at higher charge/discharge rates. For example, nano-LiMn2O4 electrode coated with 6 Al2O3 ALD layers delivers higher initial capacity (124.7 mA h/g) and final capacity (106.7 mA h/g) after 100 cycles than bare electrode with an initial capacity of 112.3 mA h/g and a final capacity of only 95.5 mA h/g, when cycled at a very high rate of 5 C at 55 degrees C. In addition, nano-LiMn2O4 electrodes show much better rate performance than micron-LiMn2O4 electrodes at 5 C. The enhanced electrochemical performance of ALD-modified LiMn2O4 is ascribed to high-quality ALD oxide coatings that are highly conformal, dense, complete, and thus protect active material from severe dissolution, and to a formed robust glass layer on the surface of LiMn2O4 that suppress its crystallographic transformation during electrochemical cycling. Surface modifications of LiMn2O4 are also carried out by either ALD coating directly onto the entire LiMn2O4/carbon/PVDF composite electrode or coating only on LiMn2O4 particles in electrode. The former results in more significantly improved electrochemical performance of cathode, possibly because ALD coating onto entire electrode provides better mechanical integrity and preserves contact between LiMn2O4 particles and carbon/poly-vinylidenefluoride network.

10.
Oxid Med Cell Longev ; 2022: 9399658, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35936221

RESUMEN

Oxidative stress, endoplasmic reticulum (ER) stress, and neuronal cell apoptosis have been considered as the main pathogenesis factors of brain injury after intracerebral hemorrhage (ICH). Chrysophanol (CHR) has been proved to have neuroprotective effects, but the role and underlying mechanisms of CHR in ICH remain unclear. HT22 cells were dealt with hemin to mimic an in vitro ICH model and then subjected to treatment with or without CHR. The cell viability, apoptosis, ER stress, and oxidative stress were evaluated by conducting the cell counting kit-8 (CCK-8), TdT-mediated dUTP nick end labeling (TUNEL) staining assays, western blot, and corresponding kit, respectively. Further, microRNA-sequencing, bioinformatic analysis, dual-luciferase reporter method, and rescue experiments were conducted to explore the molecular mechanisms of CHR alleviating hemin-induced ER in HT22 cell. Our data revealed that CHR increased cells viability, antiapoptosis, anti-ER stress, and antioxidative stress under conditions of hemin-induced HT22 cell injury. Mechanically, it was observed that Wnt3a was competitively sponged by miR-320-5p, and CHR activated ß-catenin pathway by regulating miR-320-5p/Wnt3a molecular axis. Finally, results from the rescue experiment suggested that CHR inhibited hemin-induced cells apoptosis, ER stress, and oxidative stress through regulating the miR-320-5p/Wnt3a axis in HT22 cells. In conclusion, CHR prevented hemin-induced apoptosis, ER stress, and oxidative stress via inhibiting the miR-320-5p/Wnt3a/ß-catenin pathway in HT22 cells. Our results certified that CHR could be served as a promising treatment for brain damage following ICH.


Asunto(s)
Lesiones Encefálicas , MicroARNs , Antraquinonas , Lesiones Encefálicas/metabolismo , Hemorragia Cerebral/metabolismo , Estrés del Retículo Endoplásmico , Hemina/farmacología , Humanos , MicroARNs/metabolismo , Neuronas/metabolismo , Estrés Oxidativo , Proteína Wnt3A/metabolismo , beta Catenina/metabolismo
11.
J Nanosci Nanotechnol ; 11(4): 3641-50, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21776749

RESUMEN

We have employed a simple process of anodizing Ti foils to prepare TiO2 nanotube arrays which show enhanced electrochemical properties for applications as Li-ion battery electrode materials. The lengths and pore diameters of TiO2 nanotubes can be finely tuned by varying voltage, electrolyte composition, or anodization time. The as-prepared nanotubes are amorphous and can be converted into anatase nanotubes with heat treatment at 480 degrees C. Rutile crystallites emerge in the anatase nanotube when the annealing temperature is increased to 580 degrees C, resulting in TiO2 nanotubes of mixed phases. The morphological features of nanotubes remain unchanged after annealing. Li-ion insertion performance has been studied for amorphous and crystalline TiO2 nanotube arrays. Amorphous nanotubes with a length of 3.0 microm and an outer diameter of 125 nm deliver a capacity of 91.2 microA h cm(-2) at a current density of 400 microA cm(-2), while those with a length of 25 microm and an outer diameter of 158 nm display a capacity of 533 microA h cm-2. When the 3-microm long nanotubes become crystalline, they deliver lower capacities: the anatase nanotubes and nanotubes of mixed phases show capacities of 53.8 microA h cm-2 and 63.1 microA h cm(-2), respectively at the same current density. The amorphous nanotubes show excellent capacity retention ability over 50 cycles. The cycled nanotubes show little change in morphology compared to the nanotubes before electrochemical cycling. All the TiO2 nanotubes demonstrate higher capacities than amorphous TiO2 compact layer reported in literature. The amorphous TiO2 nanotubes with a length of 1.9 microm exhibit a capacity five times higher than that of TiO2 compact layer even when the nanotube array is cycled at a current density 80 times higher than that for the compact layer. These results suggest that anodic TiO2 nanotube arrays are promising electrode materials for rechargeable Li-ion batteries.


Asunto(s)
Sustancias Intercalantes/química , Litio/química , Litio/aislamiento & purificación , Nanoestructuras/química , Nanoestructuras/ultraestructura , Titanio/química , Iones , Sustancias Macromoleculares/química , Ensayo de Materiales , Conformación Molecular , Propiedades de Superficie
12.
Sci Rep ; 10(1): 4735, 2020 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-32170188

RESUMEN

Surveying the quality and quantity of carbon stock in litter layer and woody debris of Eucalyptus and Acacia plantations is critical in understanding their carbon pools. Here, the focus of the present study was on a number of Eucalyptus and Acacia plantations of different stand aged in the Pearl River Delta region of southern China. The plantation type proved to be a crucial driver of the carbon concentration in litter layer and woody debris, with Acacia exhibiting a superior ability to Eucalyptus to accumulate carbon with stand age in both these materials. The relative contribution of the litter layer and woody debris to the carbon stock of the ecosystem was also significantly higher under mature Acacia (8% and 7%, respectively) than that under mature Eucalyptus (4% and 1%, respectively). Most of the carbon stock within the litter layer was present in the leaf debris. The carbon stock in woody debris was mainly contained in the components within the 10-20 cm diameter class during the primary decay stage, represented as snags in middle-aged and mature Acacia, and as logs for mature Eucalyptus, respectively. The results indicate that both plantation type and stand age influence the characteristics of carbon stored in litter layer and woody debris significantly.


Asunto(s)
Acacia/metabolismo , Biomasa , Carbono/análisis , Ecosistema , Eucalyptus/metabolismo , Carbono/metabolismo , China , Agricultura Forestal , Suelo/química
13.
Ann Transl Med ; 8(24): 1670, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33490182

RESUMEN

BACKGROUND: To explore the mechanisms of raw rhubarb and wine-processed rhubarb treatment in a rat model of intracerebral hemorrhage (ICH). METHODS: After adapting to their environment, 30 male Wistar rats were divided into 5 treatment groups: blank control group (CK) (normal saline), sham operation group (SICH) (normal saline), ICH model group (ICH) (normal saline), ICH + raw rhubarb enema group (RO) (raw rhubarb 3.60 g/kg), and ICH + wine-processed rhubarb enema group (WRO) (wine-processed rhubarb 3.60 g/kg). The rhubarb enema (once a day) was given since 3 days before ICH treatment, and was consistently given until 12 hours, 24 hours, 3 days, and 7 days post operation. Serum oxidative stress and inflammatory markers were detected by ELISA, and differences between raw rhubarb and wine-processed rhubarb treatment in ICH rats were screened by proteomics and metabolomics. RESULTS: Both rhubarb treatments effectively improved oxidative stress and inflammatory responses. After ICH, the proteins and metabolites in the brain tissue were significantly altered. Compared with raw rhubarb, wine-processed rhubarb had a better protective effect by dysregulating amino acid metabolism in the ICH model. CONCLUSIONS: Our study provides a basis for further research into the mechanisms of rhubarb treatment from different processing technologies, and promotes the application of rhubarb as a therapeutic approach to ICH.

14.
Environ Pollut ; 262: 114215, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32142975

RESUMEN

Microbial attributes have a great impact on soil heavy metal bioavailability, yet their influencing pathway on heavy metal accumulation in crop plants remains elusive. This study was aimed to analyze the influencing pathways of microbial attributes, including microbial biomass C and N (MBC and MBN), basal soil respiration (BSR) along with the activities of catalase, urease, and sucrase, on heavy metals (i.e., Cd, Cr, Cu, Ni, Pb, and Zn) accumulation by brassica leaves. Based upon a field investigation close to electroplating factory outlets, 45 pairs of soil and brassica samples were analyzed in the laboratory. Concentrations of heavy metals in brassica leaves declined with sampling distances downstream from the outlets. Redundancy analysis indicated that bioavailable concentrations of Cr, Cu, Ni, and MBC along with catalase activity were the major variables influencing heavy metal accumulation in brassica leaves and accounted for 83% of the accumulation. MBC and catalase activity accounted for 17% of the heavy metal accumulation in brassica leaves. Stepwise regression indicated that catalase activity, MBC, and BSR significantly affected heavy metal accumulation in brassica leaves. Based on structural equation modeling, the pathway coefficient of microbial activities-brassica heavy metals and the pathway coefficient of microbial biomass-brassica heavy metals are 0.122 (P < 0.05), suggesting that these microbial attributes (i.e. MBC along with catalase activities and SBR) could affect heavy metal accumulation in brassica leaves directly. The pathway coefficients of microbial activities-bioavailable heavy metals-brassica heavy metals and microbial biomass-bioavailable heavy metals-brassica heavy metal were -0.541 (P < 0.001) and 0.453 (P < 0.001), respectively, indicating that increase of microbial activities inhibited heavy metal accumulation while increase of microbial biomass promoted heavy metal accumulation, in brassica leaves. These results suggested that heavy metal bioavailability played a mediating role in the influencing pathways of soil microbial attributes on heavy metals in brassica leaves.


Asunto(s)
Brassica , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Hojas de la Planta/química , Suelo , Microbiología del Suelo
15.
Sci Total Environ ; 717: 137142, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32070894

RESUMEN

Carbon storage is one of the main objectives for mangrove afforestation. Planting of the exotic species Sonneratia apetala can rapidly increase the mangrove area and biomass. Here, we studied the change in vegetation and the soil carbon stocks along the chronosequence of S. apetala plantations in Qi'ao Island, China. Five sites, including rehabilitated S. apetala of different ages (1, 4, 9, and 15 years) and 40-year-old mature native Kandelia obovata forests were investigated. Vegetation biomass and the soil carbon content from 0 to 100 cm were analyzed. The ecosystem carbon density (vegetation and soil) was then calculated. A positive and linear relationship was observed between the vegetation carbon stocks and age of S. apetala. The 15-year-old S. apetala already had a similar biomass to 40-year-old K. obovata. However, its soil and ecosystem carbon densities remained lower than those of K. obovata. Different from K. obovata, the majority of the biomass of S. apetala was reserved within the stem. Mature K. obovata had a larger proportion of soil carbon stock to ecosystem carbon stock. S. apetala can accumulate biomass rapidly, but it had a lower ecosystem carbon stock than the native mature K. obovata.


Asunto(s)
Ecosistema , Biomasa , Carbono , China , Islas , Qi , Suelo
16.
Int J Biol Macromol ; 154: 1158-1165, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31756487

RESUMEN

OBJECTIVE: Fas is a positive regulator of Th17 cells differentiation in experimental autoimmune encephalomyelitis (EAE). However, its upstream regulators are still not fully determined. This study was designed to explore the upstream regulators of Fas in regulating Th17 cells differentiation in EAE. METHODS: The mouse model of EAE was established by myelin oligodendrocyte glycoprotein injection. Th17 cells differentiation was induced by IL-23, IL-6 and TGF-ß. RESULTS: Down-regulated Hsp70 and miR-374c and up-regulated Fas were observed in the spleen and brain of EAE mice. Hsp70 overexpression evidently reduced Fas protein level, but not mRNA level. The luciferase reporter assay indicated that miR-374c targets Fas. Overexpression of miR-374c down-regulated the mRNA and protein level of Fas. The concentration of IL-17A in CD4+ T-cells was reduced by miR-374c or Hsp70 overexpression, and Fas overexpression altered this trend. Hsp70 did not regulate the expression of miR-374c, and likewise, miR-374c did not regulate the expression of Hsp70. Further results suggested that Hsp70 and miR-374c regulated Fas expression through different ways to affect Th17 cells differentiation in EAE. CONCLUSIONS: This study suggested that down-regulated miR-374c and Hsp70 promote Th17 cell differentiation by inducing Fas expression in EAE.


Asunto(s)
Encefalomielitis Autoinmune Experimental/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , MicroARNs/genética , Células Th17/metabolismo , Receptor fas/genética , Animales , Diferenciación Celular , Células Cultivadas , Ratones , Ratones Endogámicos C57BL , Células Th17/patología
17.
Sci Total Environ ; 714: 136742, 2020 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-32018964

RESUMEN

Despite carbon sequestration being an important service of mangrove ecosystems, many mangrove reforestation projects have little consideration of the carbon sequestration capacity of species to be planted. Species selection is mostly based on growth rate and convenience in planting. In this study, to compare the quantity and quality of carbon stored in soil, four habitats were selected in Haijiang River Estuary, southern China to assess the contribution by different mangrove species to sediment carbon pool. Two 12-year-old mangrove forests of the exotic Sonneratia apetala and native Kandelia obovata, respectively, and the adjacent sandflat and mudflat as unvegetated referencing sites had been studied. The total sedimentary organic carbon and active sedimentary organic content in sediment suggested that after 12 years of growth, (1) mangrove forests significantly increased the organic carbon content of sediment; (2) total organic carbon in the K. obovata forest was higher than that of the S. apetala forest; but (3) the carbon pool of the K. obovata forest was less stable than that of the S. apetala forest. These results corroborated with other studies that the sediment carbon pool of S. apetala forests reached a stable state after 13 years of growth, while that of K. obovata forests gradually stabilised upon long-term (>13 years) growth. Our study confirms that K. obovata is more conducive to capture carbon in long-term mangrove reforestation projects, demonstrating that the provision of this service may not be directly related to apparently relevant plant traits such as growth rate.


Asunto(s)
Secuestro de Carbono , Carbono , China , Bosques , Rhizophoraceae , Humedales
18.
Nanotechnology ; 20(22): 225701, 2009 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-19436089

RESUMEN

Nanostructured amorphous and anatase TiO2 are both considered as high rate Li-insertion/extraction electrode materials. To clarify which phase is more desirable for lithium ion batteries with both high power and high density, we compare the electrochemical properties of anatase and amorphous TiO2 by using anodic TiO2 nanotube arrays (ATNTAs) as electrodes. With the same morphological features, the rate capacity of nanostructured amorphous TiO2 is higher than that of nanostructured anatase TiO2 due to the higher Li-diffusion coefficient of amorphous TiO2 as proved by the electrochemical impedance spectra of an amorphous and an anatase ATNTA electrode. The electrochemical impedance spectra also prove that the electronic conductivity of amorphous TiO2 is lower than that of anatase TiO2. These results are helpful in the structural and componential design of all TiO2 mesoporous structures as anode material in lithium ion batteries. Moreover, all the advantages of the amorphous ATNTA electrode including high rate capacity, desirable cycling performance and the simplicity of its fabrication process indicate that amorphous ATNTA is potentially useful as the anode for lithium ion batteries with both high power and high energy density.

19.
Biosci Rep ; 39(4)2019 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-30910847

RESUMEN

Using a case-control design, we assessed the association between single nucleotide polymorphisms of CYP3A4 gene rs4646437 polymorphism and the risk of hypertension in Chinese population. We recruited 450 hypertension patients from The First Clinical College, Henan University of Chinese Medicine between June 2017 and May 2018. There was a significant difference in genotype distribution between case group and control group (χ2 =18.169, P=0.000). The minor A allele was significantly higher in the case group than that in the control group (31.0 vs 24.8%, P=0.000, odds ratio [OR]=1.36, 95% confidence interval [95% CI]: 1.12-1.66). Significant differences were also observed in other gene models: the GA/AA genotype did not increase the risk of hypertension compared with GG genotype (OR=1.16, 95% CI: 0.90-1.49, P=0.259). Compared with GG/GA genotype, the AA genotype also increased the risk of hypertension (OR=2.34, 95% CI: 1.56-3.50, P=0.000). For additive model, the AA genotype was significantly associated with GG genotype (OR=2.25, 95% CI: 1.49-3.42, P=0.000). The same results were found for AA vs GA (OR=2.50, 95% CI: 1.60-3.89, P=0.000). For the allele genotype, the A allele frequency was significantly higher in the case group than that in the control group (31.0 vs 24.8%, P=0.002). The A allele of CYP3A4 rs4646437 was associated with an increased risk for hypertension (OR=1.36, 95% CI: 1.12-1.66, P=0.002). Our results revealed a possible genetic association between CYP3A4 gene rs4646437 and hypertension, and the AA genotype of rs4646437 increased the risk of hypertension in Chinese Han population, and this effect could be confirmed by multivariable analyses.


Asunto(s)
Citocromo P-450 CYP3A/genética , Hipertensión/genética , Polimorfismo de Nucleótido Simple , Adulto , Pueblo Asiatico/genética , Estudios de Casos y Controles , China/epidemiología , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Hipertensión/epidemiología , Masculino , Persona de Mediana Edad
20.
Biosci Rep ; 39(2)2019 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-30777926

RESUMEN

Using a case-control design, we assessed the association between single nucleotide polymorphisms (SNPs) of growth and differentiation factor 5 (GDF5)/rs143383 gene and interaction with environments and knee osteoarthritis (KOA). We recruited 288 KOA patients from the First Clinical College, Henan University of Chinese Medicine between June 2017 and May 2018. There was significant difference in genotype distribution between case group and control group (χ2 = 22.661, P=0.000). The minor C allele was significantly higher in the case group than that in the control group (20.5 vs 8.1%, P=0.000, odds ratio (OR) = 1.62, 95% confidence interval (CI): 1.29-2.03). Significant differences were also observed in other gene models. For age, all models show significant differences (P<0.05) for those whose age was more than 60 years, and no significant difference was observed for those under 60 years. For non-smoking group, there were significant differences between case group and control group, and for smoker, significance level was found in TT compared with CC and allele gene models. Patients with drinking and Bbody mass index (MI )≥ 24 also showed significant relationship between rs143383 and osteoarthritis (OA) under the following models: TT vs CC (P=0.000, P=0.018), TT/CT vs CC (P=0.043), TT vs CT/CC (P=0.000, P=0.009), and T vs C (P=0.024, P=0.000). Other gene models indicated no significance (P>0.05). Our results revealed a possible genetic association between GDF5 and KOA, and the TT genotype of rs143383 increased the risk of KOA in Chinese Han population. The interaction between GDF5 gene and drinking, smoking, and obesity further increased the risk of KOA.


Asunto(s)
Factor 5 de Diferenciación de Crecimiento/genética , Osteoartritis de la Rodilla/genética , Polimorfismo de Nucleótido Simple , Pueblo Asiatico/genética , Estudios de Casos y Controles , China/epidemiología , Femenino , Interacción Gen-Ambiente , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/epidemiología
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