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1.
Ying Yong Sheng Tai Xue Bao ; 34(10): 2757-2766, 2023 Oct.
Artículo en Chino | MEDLINE | ID: mdl-37897283

RESUMEN

Rational delineation of ecological functional areas and clarification of their driving factors are of significance for maintaining regional ecosystem stability. We assessed six ecosystem services of Sihu Lake Basin located in Jianghan Plain using InVEST and RUSLE models and recreational scoring methods. By using K-means clustering, we identified the ecosystem service bundles, and delineated the ecological functional areas in combination with ecological sensitivity and ecosystem service bundles. The dominant driving factors of different ecological functional areas were analyzed by Geodetector. The results showed that the spatial distributions of habitat quality and carbon sequestration services were similar, with high values being mainly concentrated in Changhu Lake Basin and Honghu Lake Basin. However, the spatial distributions of crop production and soil conservation services were different, with high-value areas concentrated in the northwest area with mountains. The high values of water production service were mainly concentrated in the eastern part of Honghu Lake Basin, while the high-value areas of ecological recreation service were mainly concentrated in the northwest area and the southern part of Honghu Lake Basin. The Sihu Lake Basin could be classified into crop production bundle, habitat quality bundle, and urban living bundle according to cluster analysis. The low ecological sensitivity areas accounted for 59.0% of the Sihu Lake Basin. We classified the study area into ecological restoration areas, ecological conservation areas, ecological transition areas, ecological development areas, and comprehensive use areas by combination of ecological sensitivity and ecosystem service bundles. The geodetector results indicated that the driving factors of each ecological function zone were significantly different. The natural factors significantly influenced the ecological restoration zone, while the normalized vegetation index and population density were the main influencing factors in the ecological conservation zone and the ecological development zone, respectively. Land use type was the main influencing factor in the ecological transition zone and the comprehensive use zone. The results could provide important support for coordinated regional social development and environmental protection.


Asunto(s)
Ecosistema , Lagos , China , Suelo , Conservación de los Recursos Naturales
2.
Environ Res ; 209: 112732, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35077715

RESUMEN

Decomposing cyanobacterial bloom-induced black blooms been seen as an issue in the management of freshwater ecosystems, but its effect on sulfate-reducing bacteria (SRB) in shallow freshwater lakes is not clear. The objective of this study is to present an in-depth investigation of black bloom effects on the activities and composition of SRB, as well as the interactions between SRB and other bacteria. Water and surface sediments samples were collected from a shallow freshwater lake during black and non-black blooms. Sulfate reduction rates (SRRs) in the water column were determined from the linear regression of sulfate depletion with time. Quantitative real-time polymerase chain reactions (qPCRs), targeting the dsrA gene and Illumina sequencing of 16S rDNA, were used to estimate the SRB population and SRB community structures, respectively. Our data indicate that although a higher abundance of SRB was responsible for the higher SRR in the bottom water (34.09 ±â€¯2.37 nmol mL-1 day-1) than in the surface water (14.57 ±â€¯2.91 nmol mL-1 day-1) during black blooms, cell-specific sulfate reduction rates (csSRRs) in the distinct water layers were not significantly different (P = 0.95), with the value of approximately 0.017 fmol cell-1 day-1. Additionally, Desulfomicrobium and Desulfovibrio were the two main genera of SRB in the water column during black bloom season, while Desulfobulbus, Desulfobacca and Desulfatiglans genera were identified in the sediments of both the black and non-black blooms in genera pools. Each SRB genus preferentially associated with bacteria for specific functions in the bacterial co-occurrence network, regardless of whether black booms occurred or not. These results extend our knowledge on the importance of SRB during black blooms and the adaptation of SRB to environmental changes in freshwater lakes.


Asunto(s)
Cianobacterias , Lagos , Ecosistema , Eutrofización , Lagos/química , Sulfatos
3.
Environ Sci Pollut Res Int ; 28(38): 53594-53604, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34036494

RESUMEN

The mechanism of Cu tolerance in plants and its control measures are of considerable significance for the remediation of Cu-contaminated soils. Gibberellic acid (GA3) is involved in plant growth and development and in the response to heavy metal stress. In the present study, changes in the biomass, oxidative stress response responses, and photosynthesis of spinach seedlings were examined under Cu stress with exogenous GA3 applied at concentrations of 0, 3, 5, 10, 20, 40, 60, or 80 mg L-1. Under Cu stress, the plant Cu concentration and oxidative damage were greater, photosynthetic parameters and biomass declined, and antioxidant enzyme activities and the proline concentration increased. However, spinach growth did not terminate, indicating that spinach seedlings had strong Cu tolerance. When low concentrations of GA3 (3-5 mg L-1) were added to Cu-stressed spinach seedlings, the damage caused by Cu stress to spinach seedlings was reduced, and the Cu tolerance of spinach seedlings was enhanced, which mainly manifested as reduced oxidation damage, an increased proline concentration, elevated antioxidant enzyme activities, decreased Cu concentration in leaves, and increased Cu concentration in roots, increased photosynthetic parameters, and an increased in the total biomass. In contrast, additions of GA3 at concentrations higher than 40 mg L-1 intensified oxidative damage and decreased the activities of antioxidant enzymes, photosynthetic parameters, and biomass. Additionally, the Cu concentration increased in leaves and decreased Cu concentration in roots, indicating that high concentrations of GA3 aggravated stress damage and severely influenced physiological functions in spinach seedlings. In summary, the application of 3-5 mg L-1 GA3 to spinach seedlings in Cu-contaminated soil can be used to reduce Cu toxicity to plants and increase Cu tolerance.


Asunto(s)
Plantones , Contaminantes del Suelo , Biomasa , Cobre/análisis , Cobre/toxicidad , Giberelinas , Estrés Oxidativo , Fotosíntesis , Hojas de la Planta/química , Raíces de Plantas/química , Plantones/química , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad , Spinacia oleracea
4.
Chemosphere ; 256: 127101, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32450355

RESUMEN

Previous studies of the dynamics of sulfate-reducing bacteria (SRB) and sulfur-oxidizing bacteria (SOB) have focused on deep stratified lakes. The objective of this study is to present an in-depth investigation of the structure and dynamics of sulfur bacteria (including SRB and SOB) in the water column of shallow freshwater lakes. A cyanobacterial bloom biomass (CBB)-amended mesocosm experiment was conducted in this study, in which water was taken from a shallow eutrophic lake with sulfate levels near 40 mg L-1. Illumina sequencing was used to investigate SRB and SOB species involved in CBB decomposition and the effects of the increases in sulfate input on the water column microbial community structure. The accumulation of dissolved sulfide (∑H2S) produced by SRB during CBB decomposition stimulated the growth of SOB, and ∑H2S was then oxidized back to sulfate by SOB in the water column. Chlorobaculum sequences (the main SOB species in the study) were significantly influenced by increases in sulfate input, with relative abundance increasing approximately four-fold in treatments amended with 40 mg L-1 sulfate (referred to as 40S) when compared to the treatment without additional sulfate addition (referred to as CU). Additionally, an increase in SOB number was observed from day 26-37, concurrent with the decrease in SRB number, indicating the succession of sulfur bacteria. These findings suggest that biological sulfur oxidation and succession of sulfur bacteria occur in the water column during CBB decomposition in shallow freshwater ecosystems, and the increases in sulfate input stimulate microbial sulfur oxidation.


Asunto(s)
Cianobacterias/crecimiento & desarrollo , Lagos/microbiología , Biomasa , Chlorobi , Ecosistema , Oxidación-Reducción , Sulfatos , Sulfuros , Azufre/química
5.
Ying Yong Sheng Tai Xue Bao ; 31(6): 2057-2066, 2020 Jun.
Artículo en Chino | MEDLINE | ID: mdl-34494760

RESUMEN

Understanding the response of water quality in lake to landscape pattern at different spatial scales in agricultural watershed is of great significance to water quality management. In this study, we classified seven riparian buffer zones of lakeside zone by ArcGIS and RS in the Honghu Lake, according to the five functional areas. The landscape metrics were analyzed at multiple buffer widths using Fragstats software. Mathematical statistical methods and models such as redundancy analysis were used to explore spatial relationship between water quality and landscape patterns. Results showed that: 1) The effect of landscape patterns on water quality was scale-dependent at multiple buffer widths. The highest total explanatory power between landscape characteristics and water quality was found at the 200 m buffer width, accounting for 86.1% of the total, which was the most effective spatial scale affecting water quality. 2) The landscape configuration (e.g., largest patch index, patch density) was more associated with water quality than landscape composition (e.g., the percent of landscape and evenness index). 3) The impacts of different landscape types on water quality varied. Agriculture land, affected by topography and cultivation mode, was the main influencing factor on the degradation of water quality at smaller buffer widths from 100 m to 500 m. Forests with higher density and area had more purification effect on water pollutants at the wider buffer widths from 1000 m to 5000 m. The impacts of grassland on water quality was similar with that of forests, but densely distributed urban land contributed to water quality degradation at the same buffer widths. This study could provide scientific reference for water quality management and landscape planning of lake basin in agricultural areas.


Asunto(s)
Lagos , Calidad del Agua , Agricultura , China , Monitoreo del Ambiente , Ríos
6.
Clin Exp Rheumatol ; 38(1): 58-66, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31074719

RESUMEN

OBJECTIVES: Regulatory T (Treg) cells are crucial players in the prevention of autoimmunity. Mechanistic target of rapamycin (mTOR) signalling negatively controls the development and function of Treg cells. The aim of the present study was to evaluate the effects of rapamycin, under the generic name sirolimus, on CD4+CD25+FoxP3+ Treg cells in rheumatoid arthritis (RA) patients with low disease activity or in DAS28 remission. METHODS: Fifty-five RA patients and 60 healthy controls were enrolled in this study. All patients had previously received conventional disease-modifying anti-rheumatic drugs (DMARDs) and were considered to have a low DAS28 score (≤3.2). Peripheral blood samples and clinical information were obtained at baseline and following 6 and 12 weeks of sirolimus treatment, or after 12 weeks of conventional treatment. Peripheral blood samples were also obtained from the healthy controls. The circulating levels of lymphocyte subpopulations were assessed by flow cytometry. RESULTS: Thirty-five patients received sirolimus and 20 patients continued treatment with conventional DMARDs. The absolute counts and proportions of CD4+CD25+FoxP3+ Treg cells were significantly lower in all RA patients with DAS28 ≤ 3.2 as compared with those in healthy controls. By contrast, the difference in circulating Th17 cell numbers was not significant. Sirolimus administration resulted in elevations in circulating Treg cell numbers and significant reductions in the Th17/Treg cell ratio, whereas the circulating level of Treg cells and the Th17/Treg cell ratio in patients under conventional treatment both showed a tendency of reduction. Furthermore, a greater proportion of patients under sirolimus treatment achieved DAS28-based remission at 12 weeks. CONCLUSIONS: Sirolimus can favourably expand Treg cells in RA patients with DAS28 ≤3.2, consequently restoring a healthy balance of Th17/Treg cells, which might improve the likelihood of long-term and sustained clinical remission and reduce the probability of disease flare-ups in RA.


Asunto(s)
Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Sirolimus/uso terapéutico , Linfocitos T Reguladores/citología , Células Th17/citología , Artritis Reumatoide/inmunología , Estudios de Casos y Controles , Recuento de Células , Humanos
7.
Ying Yong Sheng Tai Xue Bao ; 30(3): 941-950, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30912387

RESUMEN

The accumulation of heavy metals in soil has serious influence on plant growth and ecosystem balance. It is of great importance to explore the mechanism of plant tolerance to heavy me-tals. Although spinach is supposed to have strong Cu tolerance, the effects of Cu on mineral element absorption and cell ultrastructure are still unclear. In this study, the growth of spinach seedlings, the absorption of mineral elements and the ultrastructure of leaf cells were examined in a pot experiment. The results showed that Cu2+ accumulation in the root of spinach seedling was less than that in the shoot when CuSO4 concentration was 100 mg·L-1, with root growth being increased and shoot growth being slightly decreased. When copper concentration continued to increase, the growth parameters continuously declined. When the CuSO4 concentrations were less than 400 mg·L-1, the foliar N, K, Ca, Mg and Fe concentrations of spinach seedling increased, and that of P decreased. The concentrations of N, P and K in roots went down and that of Ca, Mg and Fe went up. All organelles in leaf cells were clearly visible. The basal granule layer was arranged orderly, and the inner and outer membranes of chloroplasts were intact. When the CuSO4 concentrations exceeded 600 mg·L-1, foliar N concentration increased while that of P, K, Ca, Mg and Fe decreased. The concentrations of N, P, K, Ca, Mg and Fe in roots declined. The cell ultrastructure of spinach seedlings substantially changed with the increases of CuSO4 treated concentrations. The chloroplast in leaf cells became rounder, the chloroplast membrane became thinner, the stroma and basal granule layer became less, and the layer accumulation height decreased. The nucleus was broken up and small black spots were found in vacuoles and cell walls, which might be attributed to the enhancement of intracellular swelling pressure caused by high accumulation of Cu2+. In conclusion, low concentration of CuSO4 had little negative effect on the life activities of spinach seedlings, and the high concentrations of CuSO4 did not terminate their growth, indicating that spinach seedlings had strong copper resistance.


Asunto(s)
Plantones , Spinacia oleracea , Cobre , Minerales , Nutrientes , Raíces de Plantas
8.
J Cancer Res Ther ; 14(Supplement): S46-S53, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29578149

RESUMEN

OBJECTIVE: We used a meta-analysis framework to examine the correlation between HIF-1α gene polymorphisms and the susceptibility to digestive cancers. METHODS: Cochrane Library Database, EMBASE, MEDLINE, Pubmed, CINAHL, Chinese Biomedical Database and Web of Science were searched without language restrictions to identify relevant case-control studies reporting data on HIF-1α gene polymorphisms in digestive cancers. Data was extracted from the selected studies and meta-analysis was carried out using STATA 12.0 and Comprehensive Meta-analysis 2.0 softwares. Relative risk (RR) and its 95% confidence interval (95%CI) were calculated. A total of 8 eligible case-control studies were included. These 8 studies contained a combined total of 1,276 patients diagnosed with various digestive cancers and 3,392 healthy controls. Two functional HIF-1α polymorphisms (rs11549465 C>T and rs11549467 G>A) were examined in these 8 studies. RESULTS: Our findings demonstrated that both rs11549465 C>T and rs11549467 G>A HIF-1α polymorphisms conferred significantly increased risk of digestive cancers. However, ethnicity-stratified analysis revealed that HIF-1α rs11549465 C>T and rs11549467 G>A polymorphisms were associated with an elevated risk of digestive cancer in Asians, but not in Caucasians. These two polymorphisms also conferred different degrees of susceptibility to various digestive cancer types. CONCLUSION: Our meta-analysis suggests that HIF-1α rs11549465 C>T and rs11549467 G>A polymorphisms influence the pathogenesis of digestive cancers in Asians.


Asunto(s)
Pueblo Asiatico/genética , Neoplasias del Sistema Digestivo/epidemiología , Neoplasias del Sistema Digestivo/genética , Predisposición Genética a la Enfermedad , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Polimorfismo de Nucleótido Simple , Alelos , Genotipo , Humanos , Vigilancia de la Población , Medición de Riesgo , Factores de Riesgo
9.
Biomed Pharmacother ; 97: 1397-1408, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29156529

RESUMEN

The non-alcoholic fatty liver disease (NAFLD) has become a serious medical problem and an increasing threat to public health. It is characterized by the abnormal fat accumulation in liver without excessive alcohol intake. The concurrent NAFLD might up-regulate the risk of chronic kidney disease as well as the mortality rate. Though various drugs have been investigated to attenuate NAFLD, further study is still necessary to find new therapeutic strategy and to reveal the underlying molecular mechanism. In the present study, NAFLD animal models were induced by feeding with high fat (HF) diet for 8 weeks. Alpinetin (ALP) was given to mice for another 8 weeks together with HF. Hepatic and renal function, oxidative stress, inflammatory response and lipid metabolism were calculated. And human liver cells of HL-7702 were cultured with high fructose (5mM) with or without ALP. The findings indicated that ALP down-regulated lipid accumulation in liver tissue samples. The higher inflammatory score induced by HF in liver and renal were reduced by ALP. HF-triggered oxidative stress was inhibited in ALP-treated groups, as evidenced by enhanced SOD1/HO-1/Nrf-2 expressions and reduced thioredoxin-interacting protein (TXNIP)/xanthine oxidase (XO) levels. ALP also suppressed inflammatory response by decreasing pro-inflammatory cytokines through inactivating toll-like receptor 4-nuclear factor kappa B (TLR4-NF-κB) pathway. The anti-oxidant and anti-inflammatory effects of ALP were confirmed in HL-7702 cells. Further, abnormal lipid metabolism caused by HF was alleviated by ALP, which was associated with the decreased Stearoyl-CoA desaturase 1 (SCD1), fatty acid synthase (FAS), sterol element regulatory binding protein 1c (SREBP-1c), Liver X Receptor (LXR)-α, elongases of very long-chain fatty acids (Elovl)-2, p-insulin receptor substrate 1 (IRS1) expressions, and increased PPARα levels. Taken together, the results above indicated that ALP could suppress oxidative stress, reduce inflammatory response and attenuate lipid metabolism, preventing NAFLD.


Asunto(s)
Flavanonas/farmacología , Inflamación/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Animales , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Línea Celular , Citocinas/metabolismo , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Humanos , Inflamación/patología , Mediadores de Inflamación/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL
10.
Huan Jing Ke Xue ; 36(4): 1285-92, 2015 Apr.
Artículo en Chino | MEDLINE | ID: mdl-26164902

RESUMEN

Based on the high-density analysis of 139 monitoring points and samples in water of honghu lake with different degrees of eutrophication during the high water-level period, we could get the figures of spatial variability characteristics of pollution factors, the biomass of aquatic plants and water quality in Honghu Lake using the GIS interpolation methods. The result showed that the concentrations of TN, TP, NH4(+) -N, permanganate index gradually increased from south to north during this period, the trend of water pollution degree in Honghu Lake was the region of inflowing rivers > enclosure culture area > open water area > the lake protection area > region of the Yangtze river into the lake; and the contribution rate of water quality parameters was in the order of TN > TP > permanganate index > NH4(+), -N > DO; under the influence of industrial sewage, agricultural sewage, domestic sewage, bait, aquatic plants and water exchange, 59% of TN, 35.2% of TP, 13.7% of permanganate index, 4.3% of NH4(+)-N exceeded the water quality targets, respectively, accordingly, 66.2% of the water quality also exceeded the water quality target. Nonetheless, DO reached the water quality target due to the influences of monsoon climate and other environment factors. The spatial variation analysis could directly reflect the mutual interaction among human activity, land-use types and environment factors which had an enormous impact on Honghu Lake water environment. In order to ensure that the lake water environment is beneficial for human productions and livings, it is necessary for us to control the discharge of industrial sewage, agricultural sewage and domestic sewage, as well as the expanding area of aquaculture, all the above measures would be significant for gradually resuming the self-purification capacity of water body and finally achieving the ecological sustainable development of Honghu Lake water environment.


Asunto(s)
Agua Dulce/química , Lagos/química , Calidad del Agua , Agricultura , China , Conservación de los Recursos Naturales , Monitoreo del Ambiente , Contaminación Ambiental , Eutrofización , Nitrógeno , Fósforo , Ríos , Aguas del Alcantarillado , Contaminantes Químicos del Agua , Contaminación del Agua
11.
Zhonghua Yi Shi Za Zhi ; 41(1): 18-22, 2011 Jan.
Artículo en Chino | MEDLINE | ID: mdl-21569695

RESUMEN

Zheng Xu Yi Qie Jing Yin Yi is great synthesis writing on pronunciation and meaning of Buddhist Scriptures and it conserves a large number of syndrome names and explanatory notes in ancient books. It is worth studying it for its important reference value for syndrome manifestation, pathogeny, source of the words, title in dialect, the words used contemporaneaously, vernacular, etc. Also explanatory notes of some syndrome names in current dictionaries could also be supplemented and corrected according to the book.

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