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1.
Biol Trace Elem Res ; 202(7): 3062-3072, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38273185

RESUMO

Chronic obstructive pulmonary disease (COPD) is now considered among the top three contributors to mortality globally. There is limited understanding surrounding the contribution of magnesium to the progression of COPD. This survey aims to evaluate the connection between dietary magnesium intake and both lung function and COPD prevalence among the US population. The research comprised 4865 participants in the National Health and Nutrition Examination Survey (NHANES) program conducted from 2007 to 2012. To evaluate the association between dietary magnesium intake and lung function as well as COPD, the study conducted multiple regression analyses, stratified analyses, and smoothed curves. In this study, we explored the relationship between higher magnesium intake and higher FEV1 [ß = 0.21 (95% CI 0.12, 0.30)] and FVC [ß = 0.25 (95% CI 0.14, 0.36)] after accounting for all potential confounding factors. We demonstrated a relationship between increased magnesium intake and reduced odds of developing COPD [OR = 0.9993 (95% CI 0.9987, 1.0000)]. The results of stratified analyses further indicated that the relationship between magnesium intake and the risk of COPD is more pronounced in the 40-60 age group and males. The study demonstrated positive associations between the intake of dietary magnesium and both FEV1 and FVC. Additionally, an adverse relationship between magnesium intake and the prevalence of COPD was also observed, suggesting that supplementation with magnesium may be a practical approach to preventing and managing COPD.


Assuntos
Magnésio , Doença Pulmonar Obstrutiva Crônica , Humanos , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Magnésio/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estudos Transversais , Feminino , Adulto , Estados Unidos/epidemiologia , Inquéritos Nutricionais , Pulmão/fisiopatologia , Pulmão/efeitos dos fármacos , Idoso , Dieta , Testes de Função Respiratória , Volume Expiratório Forçado
2.
Sci Total Environ ; 868: 161518, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-36642276

RESUMO

Cyanobacterial blooms are a major environmental problem in eutrophic reservoirs in China. Algal cells can migrate to the sediment surface in winter and maintain biological activity, which could further affect the cycling process of sediment phosphorus (P) and iron (Fe). In this study, a pilot simulation experiment was conducted to investigate the effect of overwintering cyanobacteria (Owc) on P and Fe regeneration across the sediment-water interface (SWI). Owc esterase activity ranged from 16.4 to 26.6 nmol (FDA)/(L·h), with a fluctuating increasing trend within the incubation time. Compared with the control (no Owc), Owc treatment increased the redox potential value (Eh) at the SWI but slightly decreased the pH during the first stage of this experiment (0-24 d); however, the Eh at the SWI under Owc treatment decreased to 50.9 % of that of the control on day 90. The Fe(II) could rapidly oxidized to Fe (oxyhydro)oxides and combine with phosphate in high Eh environments, and Owc inhibited P and Fe release at the SWI within 24 days; however, the continuous decrease in Eh resulted in the reduction of Fe(III). Thus, the Fe concentration measured via diffusive gradients in thin films in the Owc-treated interstitial water gradually increased to 1.92 times that of the control, promoting the release of Fe and P across the SWI. For 13 days after Owc addition, the amount of mobile P in the sediment was significantly higher than that in the control, and it gradually decreased from day 24 to 90, with the lowest being approximately 74.1 % of the amount in the control. The reactive Fe concentration in the sediment showed a similar variation trend. These results indicate that mobile P and reactive Fe in the sediment could be the main sources of regeneration across the SWI in the presence of Owc.


Assuntos
Cianobactérias , Poluentes Químicos da Água , Ferro/análise , Fósforo/análise , Eutrofização , Água , Poluentes Químicos da Água/análise , Sedimentos Geológicos , Lagos , Monitoramento Ambiental/métodos
3.
Sci Total Environ ; 806(Pt 4): 150925, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655638

RESUMO

HPLC-ICPMS was used to analyze the spatiotemporal variation of As species in different sections and tributaries of the Aha Reservoir over four seasons, and the migration and transformation mechanisms were clarified by combined analysis of hydrochemical parameters and microbial composition. The results showed that the internal release of As from the reservoir sediments is mainly due to the reduction of iron oxide and the release of adsorbed As(V). The average proportion of As(III) increased from 27.2% in autumn to 46.5% in summer, 68.9% in winter, and up to 70.8% in spring. In spring and summer, the high concentration of As(III) and organic arsenic in the epilimnion under phosphorus restriction was caused by the reductive metabolism of phytoplankton after intake of As(V). The arsenic species in the metalimnion were mainly affected by the oxidation-reduction potential (ORP). In summer and autumn, As-oxidizing bacteria used As(III) as an electron donor, and nitrate played an important role as an electron acceptor, maintaining the dominance of As(V) in the hypolimnion. However, in winter and spring, temperature-controlled ORP was the main process, which was dominated by As(III). In conclusion, As species show annual cycles in different layers of seasonally thermal stratified reservoirs. It provides a systematic mechanism of As species transformation in reservoirs, especially the effect of biological transformation mechanism.


Assuntos
Arsênio , Biotransformação , Fósforo , Fitoplâncton , Estações do Ano
4.
Environ Sci Pollut Res Int ; 29(2): 1937-1948, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34363164

RESUMO

The eutrophication of reservoirs can change the physicochemical parameters of water, thus affecting the migration and transformation of heavy metals. At present, there is insufficient research on the coupling mechanisms between nutrients and heavy metals, especially between heavy metals in suspended particles. In this paper, spatial and temporal distribution characteristics of nutrients dissolved heavy metals, and heavy metals in suspended particles were analyzed in a seasonally stratified reservoir. Combined with the nitrogen and phosphorus biogeochemical process, the coupling mechanisms between heavy metals and nutrients were discussed. The results showed that the Aha Reservoir had temperature and dissolved oxygen stratification in April and July. The reduction and dissolution of Fe and Mn oxide/hydroxide and the resuspension of sediments might result in a simultaneous increase in the concentrations of nutrients, dissolved heavy metals and heavy metals in suspended particles in hypolimnion in July and October. In the presence of dissimilatory iron-reducing bacteria (DRIB), the dissolution of iron-bound phosphorus in sediments and suspended particulate matter (SPM) might lead to the simultaneous release of iron and phosphorus into the water. The dissolution of metal sulfides in the sediments and SPM under the action of dissimilatory nitrate reduction to ammonium (DNRA) bacteria might lead to the simultaneous release of ammonia nitrogen and heavy metals into the water. Due to the coupling between nitrogen and phosphorus and heavy metals, seasonal stratified reservoir may face the risk of periodic simultaneous pollution of eutrophication and heavy metals in summer and autumn. This research provides theoretical support for the treatment of heavy metal and eutrophication combined pollution in karst areas.


Assuntos
Metais Pesados , Poluentes Químicos da Água , China , Monitoramento Ambiental , Sedimentos Geológicos , Metais Pesados/análise , Nutrientes , Fósforo/análise , Poluentes Químicos da Água/análise
5.
J Environ Manage ; 297: 113297, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34280863

RESUMO

Controlling the release of phosphorus (P) in sediments is important to prevent eutrophication and harmful algal blooms in water bodies. Here we explored the effect of mobile aerators on the control of P release from sediments in a eutrophic pond. The dissolved oxygen in the water body recovered significantly after six months of aeration, becoming 4.2-5.8 times higher than in the control. The pH and Eh values at the sediment-water interface considerably increased, while the concentration of soluble reactive phosphorus (SRP) in pore water significantly decreased, resulting in the alteration of SRP fluxes from 1.69 mg/m2 d to -53.49 mg/m2 d. Moreover, the inert P in sediments increased by 5.2% of the total P at the end of the study compared with the initial state, and the calcium-bound phosphorus (HCl-P) increased by 96.6%. However, although aeration reduced the concentration of SRP in the water column, the total P concentration was 2.45 times higher than that of the control, and the content of redox-sensitive P (BD-P) in the sediment also increased by 200%. Overall, although mobile aeration can maintain the microenvironment of the sediment interface and increase the inert P content in the sediment to reduce the P flux, it cannot reduce the risk of release of mobile P.


Assuntos
Fósforo , Poluentes Químicos da Água , Eutrofização , Sedimentos Geológicos , Proliferação Nociva de Algas , Lagos , Lagoas , Poluentes Químicos da Água/análise
6.
Environ Sci Pollut Res Int ; 27(21): 25861-25869, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31420838

RESUMO

Environmental sediment dredging is one of the most common methods for the remediation of contaminated sediments in lakes; however, debate continues as to whether the effectiveness of dredging methods contributes to this phenomenon. To determine sediment resuspension and nutrient release following dredging with a variety of dredging methods, four dredging treatments at wind speeds of 0-5.2 m/s were simulated in this study, namely suction dredging (SD), grab dredging (GD), ideal dredging with no residual sediments (ID), and non-dredging (ND). Field sediments from suction and grab dredging areas (including post-dredged and non-dredged sediments) of Lake Taihu were used to assess the release abilities of soluble reactive phosphorus (SRP) and ammonia nitrogen (NH4+-N) from the sediment-water interface. The effects of residual sediments on nutrient concentrations in water were also evaluated. The results reveal that inhibition of resuspension of particulate matter and nutrients released through sediment dredging decreases with increasing levels of residual sediment. Total suspended particulate matter content in the mean water columns of ID, SD, and GD under wind-induced disturbance (1.7-5.2 m/s) decreased by 67.5%, 56.8%, and 44.3%, respectively; total nitrogen and total phosphorus in ID (SD) treatments were 19.8% (12.9%) and 24.5% (11.2%) lower than that in ND treatment. However, there were ~ 1.6 and 1.5 times higher SRP and NH4+-N in the GD treatment compared with the ND treatment at the end of the resuspension experiment (0 m/s). A significant increase in the SRP and NH4+-N release rates at the sediment-water interface was also observed in field sediments from a grab dredging area, indicating that GD may pose a short-term risk of nutrient release to the water body. Hence, dredging methods with less residual sediments both during and after dredging improves the dredging quality.


Assuntos
Lagos , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental , Sedimentos Geológicos , Nutrientes , Fósforo/análise , Água
7.
Zhongguo Zhen Jiu ; 37(7): 705-709, 2017 Jul 12.
Artigo em Chinês | MEDLINE | ID: mdl-29231542

RESUMO

OBJECTIVE: To discuss the clinical therapeutic effects of electroacupuncture at Neimadian (Extra) and Neiguan (PC 6) on the analgesic effect of thoracic perioperative stage and its effect mechanism. METHODS: Sixty cases of esophageal cancer with elective radical resection under general anesthesia were divided into an observation group and a control group according to the operation sequence, 30 cases in each one. In the control group, the general anesthesia was simply applied and sufentanil was administered for patient controlled intravenous analgesia (PCIA) after operation. In the observation group, on the basis of the scheme as the control group, the electroacupuncture was used at Neimadian (Extra) and Neiguan (PC 6) 30 min before anesthesia induction and after operation, with continuous wave, tolerable intensity, lasting for 30 min. Separately, before acupuncture (T1) and 2h (T2), 12h (T3), 24h (T4) and 48h (T5) after operation, the plasma ß-endorphin (ß-EP), 5-hydroxytryptamine (5-HT) and prostaglandin E2 (PGE2) were determined. During operation, under the same state (from 50 to 60) of bispectrum of EEG (BIS), the intraoperative anesthetic dose was recorded. Using visual analogue scale (VAS), the pain degree was evaluated at T2, T3, T4 and T5 separately and the grade assessment of the therapeutic effects and safety were recorded at each time point. RESULTS: ①The total dosage of sufentanil in the observation group was less than that in the control group[(1.83±0.56) mg vs (2.54±0.62) mg, P<0.05]. ②VAS scores at T2, T3 and T4 in the patients of the observation group were all lower than those in the control group (all P<0.05). ③The levels of plasma ß-EP at T3, T4 and T5 in the observation group were increased significantly as compared with those in the control group (all P<0.05) and the levels of plasma 5-HT and PGE2 at T2, T3 and T4 were reduced significantly as compared with those in the control group (all P<0.05). ④ The excellent analgesia rates 2h、12h and 24h after operation in the observation group were better than those in the control group (all P<0.05). ⑤The rate of the A grade safety in the observation group was higher than that in the control group (P<0.05). CONCLUSIONS: Electroacupuncture at Neimadian (Extra) and Neiguan (PC 6) provides the safe and effective postoperative anesthesia of thoracic surgery and reduces the dosage of analgesics during the operation, which is possibly related to the increase of endogenous ß-EP and the inhibition on the release of 5-HT and PGE2.


Assuntos
Analgesia por Acupuntura , Eletroacupuntura/métodos , Neoplasias Esofágicas/cirurgia , Pontos de Acupuntura , Anestesia Geral , Anestésicos Intravenosos/administração & dosagem , Pesquisa Biomédica , Estudos de Casos e Controles , Dinoprostona/sangue , Humanos , Manejo da Dor , Medição da Dor , Serotonina/sangue , Sufentanil/administração & dosagem , beta-Endorfina/sangue
8.
Environ Monit Assess ; 188(1): 8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26631398

RESUMO

Nutrient transport and loss in farmlands are affected by factors such as land cover, fertilization, soil type, rainfall, and management practices. We investigated the temporal and spatial changes in macronutrient transport and loss after fertilization and precipitation in manure-fertilized eggplant farmland in an alluvial plain. Upon adding topical fertilizer, concentrations of most nutrients in runoff and groundwater increased, and nitrogen runoff increased from 22.11 to 35.81 kg/ha, although eggplant yield did not increase correspondingly. Incorporation of fertilizer by plowing reduced nutrient losses (nitrogen runoff/fertilizer decreased from 18.40 to 12.29 %). Measurements taken along the nutrient transport route (runoff, drainage ditch, groundwater, river water, and finally rainfall) revealed that concentrations of most nutrients declined at each stage. Nutrient characteristics varied by transport, and the forms of nitrogen and phosphorus differed greatly between runoff and groundwater (nitrate/nitrogen in runoff was ~43.49 %, while in groundwater ~5.41 %). Most nutrient concentrations in runoff decreased greatly during the planting season (total nitrogen decreased from 62.25 to 4.17 mg/L), correlated positively with temperature and stage of plant growth, but little temporal change was observed in groundwater. This field investigation during one planting season exemplifies the basic principles of nutrient loss and transport from manure-fertilized farmland in an alluvial plain.


Assuntos
Agricultura , Monitoramento Ambiental , Esterco/análise , Nitrogênio/análise , Fósforo/análise , Chuva , Poluentes do Solo/análise , Fertilizantes , Água Subterrânea , Solo/química , Movimentos da Água
9.
Zhongguo Zhong Yao Za Zhi ; 39(8): 1499-501, 2014 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-25039190

RESUMO

OBJECTIVE: To discuss the anti-tumor effect of Xihuang pill on tumor-bearing rats and its effect on the immune clearance function of tumor-bearing organisms. METHOD: Walker256 tumor cells were adopted to establish the tumor-bearing rat model. The rats were randomly divided into five groups: the normal control group, the model control group, the lentinan group and Xihuang pill low dose, middle dose and high dose groups, with 10 rats in each group, and continuously treated and given drugs for 14 d after modeling. Blood and tumors were collected from abdominal aorta to calculate the tumor inhibition rate. The content of CD3+, CD4+, CD8+ T cells and adhesion molecule B7-1 (CD80) in peripheral blood were detected by flow cytometry (FCM). The expressions of IL-2 and IFN-gamma in were determined by ELISA. RESULT: The tumor inhibition rate of the Xihuang pill high dose group was 33. 1 percent. Compared with the model group, the Xihuang pill large dose group showed significantly low IL-2, IFN-gamma, CD3+, CD4+, B7-1 in peripheral blood, with statistical significance in their differences (P < 0.05). CONCLUSION: Xihuang pill could show its anti-tumor effect by enhancing the immune clearance function and increasing IL-2, IFN-gamma, CD3+ T, CD4+ T, B7-1 in peripheral blood.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/imunologia , Medicamentos de Ervas Chinesas/administração & dosagem , Fatores Imunológicos/administração & dosagem , Animais , Antígeno B7-1/genética , Antígeno B7-1/imunologia , Neoplasias da Mama/genética , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Feminino , Citometria de Fluxo , Humanos , Sistema Imunitário/efeitos dos fármacos , Interferon gama/genética , Interferon gama/imunologia , Interleucina-2/genética , Interleucina-2/imunologia , Ratos , Ratos Wistar , Carga Tumoral/efeitos dos fármacos
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