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1.
Sci Total Environ ; 935: 173430, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-38782273

RESUMO

The prevalence of pollen allergies is a pressing global issue, with projections suggesting that half of the world's population will be affected by 2050 according to the estimation of the World Health Organization (WHO). Accurately forecasting pollen allergy risks requires identifying key factors and their thresholds for aerosol pollen. To address this, we developed a technical framework combining advanced machine learning and SHapley Additive exPlanations (SHAP) technology, focusing on Beijing. By analyzing meteorological data and vegetation phenology, we identified the factors influencing next-day's pollen concentration (NDP) in Beijing and their thresholds. Our results highlight vegetation phenology data from Synthetic Aperture Radar (SAR), temperature, wind speed, and atmospheric pressure as crucial factors in spring. In contrast, the Normalized Difference Vegetation Index (NDVI), air temperature, and wind speed are significant in autumn. Leveraging SHAP technology, we established season-specific thresholds for these factors. Our study not only confirms previous research but also unveils seasonal variations in the relationship between radar-derived vegetation phenology data and NDP. Additionally, we observe seasonal fluctuations in the influence patterns and threshold values of daily air temperatures on NDP. These insights are pivotal for improving pollen concentration prediction accuracy and managing allergic risks effectively.


Assuntos
Poluentes Atmosféricos , Alérgenos , Monitoramento Ambiental , Aprendizado de Máquina , Pólen , Estações do Ano , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Alérgenos/análise , Pequim , Poluição do Ar/estatística & dados numéricos
2.
Physiol Plant ; 176(1): e14195, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38332400

RESUMO

This review aims to elucidate the intricate effects and mechanisms of terahertz (THz) wave stress on Pinellia ternata, providing valuable insights into plant responses. The primary objective is to highlight the imperative for future research dedicated to comprehending THz wave impacts across plant structures, with a specific focus on the molecular intricacies governing root system structure and function, from shoots to roots. Notably, this review highlights the accelerated plant growth induced by THz waves, especially in conjunction with other environmental stressors, and the subsequent alterations in cellular homeostasis, resulting in the generation of reactive oxygen species (ROS) and an increase in brassinosteroids. Brassinosteroids are explored for their dual role as toxic by-products of stress metabolism and vital signal transduction molecules in plant responses to abiotic stresses. The paper further investigates the spatio-temporal regulation and long-distance transport of phytohormones, including growth hormone, cytokinin, and abscisic acid (ABA), which significantly influence the growth and development of P. ternata under THz wave stress. With a comprehensive review of Reactive oxygen species (ROS) and Brassinosteroid Insensitive (BRI) homeostasis and signalling under THz wave stress, the article elucidates the current understanding of BRI involvement in stress perception, stress signalling, and domestication response regulation. Additionally, it underscores the importance of spatio-temporal regulation and long-distance transport of key plant hormones, such as growth hormone, cytokinin, and ABA, in determining root growth and development under THz wave stress. The study of how plants perceive and respond to environmental stresses holds fundamental biological significance, and enhancing plant stress tolerance is crucial for promoting sustainable agricultural practices and mitigating the environmental burdens associated with low-tolerance crop cultivation.


Assuntos
Brassinosteroides , Pinellia , Brassinosteroides/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Pinellia/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Ácido Abscísico/metabolismo , Estresse Fisiológico , Citocininas/metabolismo , Plantas/metabolismo , Hormônio do Crescimento/metabolismo , Hormônio do Crescimento/farmacologia
3.
Front Mol Neurosci ; 16: 1246842, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37840772

RESUMO

This study explores the implications of a novel germline missense mutation (R38C) in the succinate dehydrogenase (SDH) subunit B, which has been linked to neurodegenerative diseases. The mutation was identified from the SDH mutation database and corresponds to the SDH2R32C allele, mirroring the human SDHBR38C mutation. By subjecting the mutant yeast model to hydrogen peroxide (H2O2) stress, simulating oxidative stress, we observed heightened sensitivity to oxidative conditions. Quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) analysis revealed significant regulation (p < 0.05) of genes associated with antioxidant systems and energy metabolism. Through gas chromatography-mass spectrometry (GC-MS) analysis, we examined yeast cell metabolites under oxidative stress, uncovering insights into the potential protective role of o-vanillin. This study elucidates the biological mechanisms underlying cellular oxidative stress responses, offering valuable insights into its repercussions. These findings shed light on innovative avenues for addressing neurodegenerative diseases, potentially revolutionizing therapeutic strategies.

4.
Huan Jing Ke Xue ; 44(8): 4706-4716, 2023 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-37694663

RESUMO

It is important to understand the spatial distribution characteristics and health risks of soil heavy metals for the implementation of soil pollution control measures in different levels and regions. Based on the data of 706 core studies in the last 20 years, the spatial distribution characteristics, accumulation degree, and health risks of soil heavy metals in China were analyzed at the provincial level. The results showed that the soil heavy metals had obvious spatial differences on the provincial scale, with an overall trend of "high in the south and low in the north and high in the east and low in the west." The content of heavy metals in the soil of agricultural land and construction land was high, and the rate of exceeding the standard was higher than that of other land types. Soil heavy metal concentrations in most areas of China were higher than the regional background values and were highly cumulative. The accumulation indices were:Cd(1.80)>Pb(0.23)>Cu(0.17)>Zn(-0.05)>As(-0.56)>Cr(-0.69), with more than 85% of the provincial soils reaching moderate levels of Cd pollution. Non-ferrous metal resource-based provinces such as Yunnan, Guizhou, Guangxi, Hunan, and Jiangxi generally had higher soil heavy metal levels than those in other provinces, and local children faced higher cancer risks. Soil pollution in coastal areas such as Fujian, Zhejiang, Jiangsu, and Tianjin mainly originated from industrial production and urbanization construction. High intensity agricultural utilization was an important cause of soil heavy metal accumulation in Henan, Shandong, and Anhui.

5.
Sci Total Environ ; 873: 162371, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36828066

RESUMO

The accurate identification of pollution sources is essential for the prevention and control of possible pollution from soil heavy metals (SHMs). However, the positive matrix factorisation (PMF) model has been widely used as a conventional method for pollution source apportionment, and the classification of source apportionment results mainly relies on existing research and expert experience, which can result in high subjectivity in the source interpretation. To address this limitation, a comprehensive source apportionment framework was developed based on advanced machine learning techniques that combine self-organizing mapping and PMF with a gradient boosting decision tree (GBDT) model. Analysis of Cd, Pb, Zn, Cu, Cr, and Ni in 272 topsoils showed that the average contents of six heavy metals were 1.72-13.79 times greater than corresponding background values, among which Cd pollution was relatively serious, with 66.91 % of the sites having higher values than the specified soil risk screening values. The PMF results revealed that 79.43 % of Pb was related to vehicle emissions and atmospheric deposition, 79.32 % of Cd and 38.84 % of Zn were related to sewage irrigation, and 85.97 % of Cr and 85.50 % of Ni were from natural sources. Moreover, the GBDT detected that industrial network density, water network density, and Fe2O3 content were the major drivers influencing each pollution source. Overall, the novelty of this study lies in the development of an improved framework based on advanced machine learning techniques that led to the accurate identification of the sources of SHM pollution, which can provide more detailed support for environmental protection departments to propose targeted control measures for soil pollution.

6.
Sci Total Environ ; 857(Pt 3): 159636, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36280075

RESUMO

The accurate identification of pollution sources is important for controlling soil pollution. However, the widely used Positive matrix factorization (PMF) model generally relies on knowledge and experience to accurately identify pollution sources; thus, this method faces significant challenges in objectively identifying soil pollution sources. Herein, we established a comprehensive source analysis framework using factor identification and geospatial analysis, and revealed the factors contributing to trace metal(loid) (TM) pollution in soil in the Pearl River Delta (PRD), China. Using the PMF model, we initially considered that the PRD may be affected by natural, atmospheric, traffic and industrial, and agricultural sources. Moreover, Geodetector model detected the relationship between TMs and 12 environmental variables based on the strong spatial "source-sink" relationship of pollutants. The parent material and digital elevation model were the key factors predicting the accumulation of Cr, Ni, and Cu. Industries and roads were the most important determinants of Pb, Zn, and Cd, whereas atmospheric deposition was more important for Hg accumulation. The accumulation of As was found to be closely related to agricultural activities such as the application of chemical fertilizers and pesticides. The spatial autocorrelation between soil TM pollution and environmental variables further supports this hypothesis. Overall, the obtained results showed that proposed approach improved the accuracy of source apportionment and provided a basis for soil pollution control.


Assuntos
Metais Pesados , Poluentes do Solo , Oligoelementos , Metais Pesados/análise , Poluentes do Solo/análise , Monitoramento Ambiental , Poluição Ambiental/análise , Solo , Oligoelementos/análise , Análise Espacial , China , Medição de Risco
7.
Chemosphere ; 301: 134551, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35405191

RESUMO

Biochar can be effective in immobilizing soil cadmium (Cd), but the difference in its immobilization mechanisms for different levels of Cd-contaminated soils was overlooked. In this study, rice straw biochar (BC) was added to three Cd-contaminated soils following 180 days of incubation, in the process of which the dynamic changes of Cd speciation, soil properties and microbial community diversity were determined. BC could significantly reduce the ratio of acid-soluble in the three soils, especially in light and medium Cd-contaminated soils by more than 20%. The addition of biochar could significantly increase the soil pH, soil organic matter, cation exchange capacity, and the activities of catalase, but decrease the richness and diversity of bacterial communities in all soils. The associations between microbial communities were inhibited in light and medium Cd-contaminated soils, but promoted in heavy Cd-contaminated soils. Furthermore, the main pathway of BC effect on soil Cd availability was also analyzed by partial least squares model (PLS-PM), which indicated that BC indirectly reduced Cd availability mainly by regulating the microbial community in light Cd-contaminated soil, whereas BC directly reduced Cd availability primarily by its own adsorption in medium and heavy Cd-contaminated soils. This research deepened understanding of the mechanisms of stabilization of Cd by biochar for agricultural soils.


Assuntos
Microbiota , Oryza , Poluentes do Solo , Cádmio/análise , Carvão Vegetal/química , Oryza/química , Solo/química , Poluentes do Solo/análise
8.
Drug Deliv ; 25(1): 690-702, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29484910

RESUMO

Pingyangmycin (PYM) has been applied clinically for many years to treat vascular malformations (VM) in China. The major limitation of PYM injections is quick diffusion from the injection site, which increases side effects, especially the possibility of pulmonary injury. In this paper, chitosan/glycerophosphate disodium (CS/GP) thermogels containing liposomes for sustained and localized PYM delivery were prepared and optimized by a three-level three-factorial Box-Behnken experimental design to evaluate the effects of different variables (the PYM concentration, CS amount and GP content), on the selected responses (cumulative percentage PYM released in 1 day, 9 days and the rate constant k). The results revealed that the optimized PYM liposomal thermogels had a controlled PYM release for 14 days in vitro, which confirmed the validity of optimization. In vitro morphological observation, cell cycle and apoptosis analysis showed an effective anti-proliferation action of PYM liposomal thermogels on human vascular endothelial cells (EA.hy926). In vivo pharmacokinetics research in rabbits displayed that compared with PYM liposomes and PYM thermogels, PYM liposomal thermogels had a better controlled delivery of PYM. Histological examination of rabbit ear veins showed that after local application with PYM lipsomal thermogels for 21 days, obvious vein thrombosis and inflammatory reaction could be observed. The above results indicated that PYM-loaded lipsomal CS/GP thermogels might have a good prospect for the treatment of VM.


Assuntos
Bleomicina/análogos & derivados , Quitosana/química , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Lipossomos/química , Animais , Apoptose/efeitos dos fármacos , Bleomicina/administração & dosagem , Bleomicina/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Glicerofosfatos/química , Humanos , Coelhos
9.
Int J Pharm ; 486(1-2): 356-66, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25840274

RESUMO

The study was aimed to evaluate the antitumor potential of the Ala-Pro-Arg-Pro-Gly (APRPG)-modified angiogenic vessel targeting drug delivery system using paclitaxel (PTX) as a model drug. In this study, an angiogenesis homing peptide APRPG was conjugated to the amphipathic copolymer PLGA-PEG and the synthesized copolymer APRPG-PEG-PLGA was used to prepare PTX encapsulated micelles (APRPG-PEG-Mic). The micelles were uniform spherical and exhibited a unimodal particle size distribution and a slight negative zeta-potential. The in vitro drug release result demonstrated a significant sustained release property of APRPG-PEG-Mic. Compared to Taxol(®) and Cont-PEG-Mic, APRPG-PEG-Mic showed a stronger cytotoxicity against two cancerous cell lines. In the cell uptake studies, the APRPG-modified micelles enhanced intracellular fluorescent intensity in EA.hy926 cells. The biodistribution study revealed the accumulation of APRPG-PEG-Mic in tumor tissues as a result of passive accumulation and active targeting. In comparison with Taxol(®) and Cont-PEG-Mic, APRPG-PEG-Mic reduced the tumor volume more significantly and prolonged the survival time of tumor-bearing mice, indicating a higher antitumor efficacy and lower systematic side effects of APRPG-PEG-Mic. The results indicated that APRPG-modified micelles could be an efficient target-delivery method to angiogenic vessels and a highly promising therapeutic system in anticancer therapy.


Assuntos
Antineoplásicos Fitogênicos , Sistemas de Liberação de Medicamentos , Micelas , Oligopeptídeos , Paclitaxel , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacocinética , Transporte Biológico , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Humanos , Masculino , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Neovascularização Patológica/tratamento farmacológico , Oligopeptídeos/administração & dosagem , Oligopeptídeos/química , Oligopeptídeos/farmacocinética , Paclitaxel/administração & dosagem , Paclitaxel/química , Paclitaxel/farmacocinética , Polietilenoglicóis/química , Poliglactina 910/química , Distribuição Tecidual , Carga Tumoral/efeitos dos fármacos
10.
Zhonghua Nei Ke Za Zhi ; 52(9): 749-52, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24314165

RESUMO

OBJECTIVE: To evaluate the effect of aranidipine enteric-coated capsules on 24 h blood pressure and blood pressure variability (BPV) in patients with mild to moderate essential hypertension. METHODS: This was an open clinical trial with 2 weeks of placebo run-in period. A total of 74 patients with blood pressure (140-180/95-110 mm Hg (1 mm Hg = 0.133 kPa) were treated by aranidipine (5 mg/d) for 4 weeks.If clinical sitting blood pressure < 140/90 mm Hg at 4th week, aranidipine at 5 mg/d would be continued for another 8 weeks.If not, the dosage would be increased to 10 mg/d.If blood pressure <140/90 mm Hg at 8th week, aranidipine at 5 mg/d or 10 mg/d would be given constantly.If not, the dosage would be increased to 20 mg/d and given for another 4 weeks. All patients performed 24 h ambulatory blood pressure monitoring (ABPM) before and after the treatment with BPV evaluated by the average 24 h per unit time blood pressure standard deviation and morning blood pressure surge (MBPS). RESULTS: (1) After 12 weeks' treatment with aranidipine, the mean 24 h blood pressure was reduced significantly compared with the baseline [(14 ± 13)/(11 ± 9) mm Hg, both P < 0.05] with trough/peak (T/P) ratio of SBP and DBP in responders of 75.31% and 78.15%, respectively.(2) After 12 weeks' treatment, standard deviations of 24 h, daytime SBP/DBP and nighttime SBP/DBP were reduced significantly[(25 ± 3)/(14 ± 4) mm Hg vs (11 ± 3)/(8 ± 2) mm Hg, (24 ± 5)/(14 ± 4) mm Hg vs (11 ± 3)/(8 ± 2) mm Hg, (10 ± 3)/(8 ± 4) mm Hg vs (8 ± 3)/(6 ± 3) mm Hg], respectively with all P < 0.05.Significant decrease was shown in MBPS compared to the baseline [(27 ± 11) mm Hg vs (19 ± 9) mm Hg, P < 0.05]. (3) The incidence of adverse events was 13.4%, including mild dizziness, flushing and palpitation. CONCLUSION: Administration of aranidipine enteric-coated capsules can control 24 h blood pressure effectively and reduce BPV significantly in patients with mild to moderate essential hypertension with good safety profile.


Assuntos
Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Di-Hidropiridinas/uso terapêutico , Hipertensão/tratamento farmacológico , Adolescente , Adulto , Idoso , Anti-Hipertensivos/administração & dosagem , Monitorização Ambulatorial da Pressão Arterial , Di-Hidropiridinas/administração & dosagem , Hipertensão Essencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Zhonghua Yi Xue Za Zhi ; 93(39): 3104-10, 2013 Oct 22.
Artigo em Chinês | MEDLINE | ID: mdl-24417987

RESUMO

OBJECTIVE: To assess the efficacy and safety of aranidipine versus retard-released felodipine in Chinese patients with mild-to-moderate essential hypertension. METHODS: This was a multicenter, randomized, double-blind, placebo and active antihypertensive drug parallel-controlled study. After 2 weeks of placebo run-in period, 315 patients at 6 centers with diastolic blood pressure (DBP) between 95 to 109 mm Hg (1 mm Hg = 0.133 kPa) while systolic blood pressure (SBP) below 180 mm Hg were randomized to receive aranidipine 5-20 mg/d (n = 126) or retard-released felodipine 5-10 mg/d (n = 126) for 12 weeks. Others (n = 63) received placebo for 4 weeks. Their blood pressures were evaluated at baseline and the end of Weeks 4, 8 and 12. RESULTS: After a 12-week treatment, SBP decreased from 148.8 ± 10.7 mm Hg to (132.8 ± 11.2) mm Hg while DBP dropped from ( 98.4 ± 2.8) mm Hg to (83.9 ± 7.5) mm Hg. There were significant differences with the baseline values (P < 0.0001). After a 4-week treatment, the reductions of SBP in aranidipine and retard-released felodipine groups were (12.1 ± 11.0) mm Hg and (12.2 ± 11.2) mm Hg while the reductions of DBP in two groups (11.8 ± 6.9) mm Hg and (12.1 ± 7.9) mm Hg respectively. The reductions of SBP and DBP in two groups were (2.3 ± 8.4) mm Hg and (4.0 ± 5.1) mm Hg and they were significantly superior to that in placebo group (P < 0.0001). But no significant difference existed between aranidipine and retard-released felodipine groups. Also no significant differences were found between these two antihypertensive therapy groups at the end of Weeks 4, 8 and 12 in the reduction of blood pressure, total response rate and blood pressure control rate. But 20 mg daily aranidipine was significantly superior to 10 mg daily retard-released felodipine in the control rates of SBP and DBP. Adverse events occurred at 24.22% and 29.92% in aranidipine and retard-released felodipine groups respectively (P = 0.305). CONCLUSION: Administration of aranidipine 5-20 mg/d can effectively control blood pressure and is not inferior to retard-released felodipine 5-10 mg/d. The efficacy of 20 mg/d aranidipine is superior to that of retard-released felodipine 5-10 mg/d. And the effectiveness and safety of aranidipine are similar to those of retard-released felodipine.


Assuntos
Anti-Hipertensivos/uso terapêutico , Di-Hidropiridinas/uso terapêutico , Hipertensão/tratamento farmacológico , Di-Hidropiridinas/administração & dosagem , Método Duplo-Cego , Hipertensão Essencial , Felodipino/administração & dosagem , Felodipino/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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