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2.
Huan Jing Ke Xue ; 45(2): 1090-1097, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471946

RESUMO

A farmland area in Zhaotong City was taken as the research object, and the method of point-to-point collaborative sampling was used to collect farmland soil and vegetables in Zhaotong and test the content of six heavy metals, namely As, Pb, Cu, Zn, Cd, and Cr. The geo-accumulation index and potential ecological risk index were used to evaluate the heavy metal pollution of soil. The health risk model was used to evaluate the risk to the human body imposed by vegetables. The results showed that Cu, Zn, Pb, Cd, and Cr pollution existed in the research area. Compared with the risk screening value of farmland, the over-standard rates were 34.35%, 6.87%, 2.29%, 80.15%, and 6.11%, respectively; Pb, Cd, and Cr were found in vegetables. Compared with the pollutant limit in food, the over-standard rates were 6.87%, 15.27%, and 36.64%, respectively. According to the soil pollution evaluation, Cd in the soil showed a strong ecological risk, and other heavy metals in the soil showed a mild ecological risk. The human health risk evaluation model showed that both non-carcinogenic risk and carcinogenic risk were out of the acceptable range and had a greater influence on children. Correlation analysis showed that As in the soil had an antagonistic effect on Cu and Zn absorption by vegetables, whereas Cr in the soil could promote Cu and Zn absorption by vegetables.


Assuntos
Metais Pesados , Poluentes do Solo , Criança , Humanos , Solo , Fazendas , Verduras , Cádmio , Chumbo , Monitoramento Ambiental/métodos , Poluentes do Solo/análise , Metais Pesados/análise , Poluição Ambiental , Medição de Risco , China
3.
Sci Total Environ ; 874: 162624, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-36878300

RESUMO

As a major component of the cryosphere, permafrost plays important roles in the climate system and land surface processes of the Earth. Owing to the rapidly warming climate, permafrost over the globe has degraded in recent decades. However, quantifying the distribution and temporal changes in permafrost is challenging. In this study, we modified the widely used surface frost number model by considering the spatial distribution of soil hydrothermal properties and then revisited the spatiotemporal patterns of permafrost distribution and its changes during the past decades (1961-2017) in China. We found that the modified surface frost number model performs well in simulating permafrost extent in China, with the overall accuracy and kappa coefficients being 0.92 and 0.78 in the calibration (1980s) and 0.94 and 0.77 in the validation period (2000s). Based on the modified model, we also found that permafrost extent in China demonstrated a significant decreasing trend over the past decades, especially on the Qinghai-Tibet Plateau (QTP), with a trend of -1.15 × 104 km2/yr (P < 0.01). Moreover, there is a significant relationship between ground surface temperature and permafrost distribution area, with the R2 being 0.41, 0.42, and 0.77 in NE and NW China and on the QTP. The sensitivity of permafrost extent to ground surface temperature in NE China, NW China, and the QTP, respectively, was -8.56 × 104, -1.97 × 104, and -34.60 × 104 km2/°C, respectively. Permafrost degradation has accelerated since the late 1980s, possibly due to increased climate warming. This study is of great significance for improving permafrost distribution simulation at large spatial scales (trans-regional) and for offering vital information for adapting to climate change in cold regions.

4.
Toxics ; 11(3)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36977033

RESUMO

Arable soils are crucial for national development and food security; therefore, contamination of agricultural soils from potentially toxic elements (PTEs) is a global concern. In this study, we collected 152 soil samples for evaluation. Considering the contamination factors and using the cumulative index and geostatistical methods, we investigated the contamination levels of PTEs in Baoshan City, China. Using principal component analysis, absolute principal component score-multivariate linear regression, positive matrix factorization, and UNMIX, we analyzed the sources and quantitatively estimated their contributions. The average Cd, As, Pb, Cu, and Zn concentrations were 0.28, 31.42, 47.59, 100.46, and 12.36 mg/kg, respectively. The Cd, Cu, and Zn concentrations exceeded the corresponding background values for Yunnan Province. The combined receptor models showed that natural and agricultural sources contributed primarily to Cd and Cu and As and Pb inputs, accounting for 35.23 and 7.67% pollution, respectively. Industrial and traffic sources contributed primarily to Pb and Zn inputs (47.12%). Anthropogenic activities and natural causes accounted for 64.76 and 35.23% of soil pollution, respectively. Industrial and traffic sources contributed 47.12% to pollution from anthropogenic activities. Accordingly, the control of industrial PTE pollution emissions should be strengthened, and awareness should be raised to protect arable land around roads.

5.
Environ Manage ; 71(5): 965-980, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36414689

RESUMO

The Hawaiian Islands have been identified as a global biodiversity hotspot. We examine the Normalized Difference Vegetation Index (NDVI) using Climate Data Records products (0.05 × 0.05°) to identify significant differences in NDVI between neutral El Niño-Southern Oscillation years (1984, 2019) and significant long-term changes over the entire time series (1982-2019) for the Hawaiian Islands and six land cover classes. Overall, there has been a significant decline in NDVI (i.e., browning) across the Hawaiian Islands from 1982 to 2019 with the islands of Lana'i and Hawai'i experiencing the greatest decreases in NDVI (≥44%). All land cover classes significantly decreased in NDVI for most months, especially during the wet season month of March. Native vegetation cover across all islands also experienced significant declines in NDVI, with the leeward, southwestern side of the island of Hawai'i experiencing the greatest declines. The long-term trends in the annual total precipitation and annual mean Palmer Drought Severity Index (PDSI) for 1982-2019 on the Hawaiian Islands show significant concurrent declines. Primarily positive correlations between the native ecosystem NDVI and precipitation imply that significant decreases in precipitation may exacerbate the decrease in NDVI of native ecosystems. NDVI-PDSI correlations were primarily negative on the windward side of the islands and positive on the leeward sides, suggesting a higher sensitivity to drought for leeward native ecosystems. Multi-decadal time series and spatially explicit data for native landscapes provide natural resource managers with long-term trends and monthly changes associated with vegetation health and stability.


Assuntos
Clima , Ecossistema , Havaí , Fatores de Tempo , Ilhas , Mudança Climática , Temperatura
6.
Front Immunol ; 12: 713001, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34733272

RESUMO

Background: IL27 has been reported to play dual roles in cancer; however, its effects on the tumor microenvironment (TME), immunotherapy, and prognosis in melanoma remain largely unclear. This study was aimed to uncover the effects of IL27 on TME, immunotherapy and prognosis in patients with melanoma. Methods: RNA-seq data, drug sensitivity data, and clinical data were obtained from TCGA, GEO, CCLE, and CTRP. Log-rank test was used to determine the survival value of IL27. Univariate and multivariate Cox regression analyses were employed to determine the independent predictors of survival outcomes. DAVID and GSEA were used to perform gene set functional annotations. ssGSEA was used to explore the association between IL27 and immune infiltrates. ConsensusClusterPlus was used to classify melanoma tissues into hot tumors or cold tumors. Results: Clinically, IL27 was negatively correlated with Breslow depth (P = 0.00042) and positively associated with response to radiotherapy (P = 0.038). High IL27 expression showed an improved survival outcome (P = 0.00016), and could serve as an independent predictor of survival outcomes (hazard ratio: 0.32 - 0.88, P = 0.015). Functionally, elevated IL27 expression could induce an enhanced immune response and pyroptosis (R = 0.64, P = 1.2e-55), autophagy (R = 0.37, P = 7.1e-17) and apoptosis (R = 0.47, P = 1.1e-27) in patients with melanoma. Mechanistically, elevated IL27 expression was positively correlated with cytotoxic cytokines (including INFG and GZMB), enhanced immune infiltrates, and elevated CD8/Treg ratio (R = 0.14, P = 0.02), possibly driving CD8+ T cell infiltration by suppressing ß-catenin signaling in the TME. Furthermore, IL27 was significantly associated with hot tumor state, multiple predictors of response to immunotherapy, and improved drug response in patients with melanoma. Conclusions: IL27 was correlated with enriched CD8+ T cells, desirable therapeutic response and improved prognosis. It thus can be utilized as a promising modulator in the development of cytokine-based immunotherapy for melanoma.


Assuntos
Biologia Computacional , Suscetibilidade a Doenças , Interleucina-27/metabolismo , Melanoma/etiologia , Melanoma/metabolismo , Biomarcadores , Terapia Combinada , Biologia Computacional/métodos , Bases de Dados Genéticas , Gerenciamento Clínico , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Interleucina-27/genética , Melanoma/patologia , Melanoma/terapia , Anotação de Sequência Molecular , Prognóstico , Análise de Sobrevida , Resultado do Tratamento
7.
Zhen Ci Yan Jiu ; 32(4): 285-8, 2007 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17907396

RESUMO

In the present paper, the authors review the current development of studies on mechanisms of acupuncture treatment of acute ischemic cerebral apoplexy from (1) blood rheology, (2) cerebral microcirculation, 3) metabolism of cerebral tissue, (4) cerebral electrical activity, (5) free radicals and lipid peroxidation reaction, (6) excitatory aminoacid, (7) calcium overload, (8) nitrogen monoxidum, and (9) cerebral apoptosis. Cerebral stroke includes ischemic stroke and hemorrhagic stroke. Ischemic cerebral stroke accounted for about 60%-70% of all the stroke cases. At present, the main remedies for treating acute ischemic cerebral stroke includes thrombolysis, anti-platelet aggregation, improving microcirculation and symptomatic therapy. In stroke, highlighting the efficacy of acupuncture therapy in the treatment of stroke.


Assuntos
Terapia por Acupuntura , Isquemia Encefálica/terapia , Acidente Vascular Cerebral/terapia , Doença Aguda , Apoptose , Cálcio/metabolismo , Radicais Livres , Humanos , Peroxidação de Lipídeos , Óxido Nítrico/toxicidade
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