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1.
Environ Pollut ; 343: 123204, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38142807

RESUMEN

Colloid-facilitated phosphorus (P) migration plays an important role in P loss from farmland to adjacent water bodies. However, the dynamics of colloidal P (Pcoll) release as influenced by irrigation in alkaline calcareous soil remains a knowledge gap. The present study, monitored the dynamic change of Pcoll under different water management strategies: 1) control, 2) flooding, and 3) alternating flooding and drying cycles. Soil water-dispersible colloids (0.6 nm-1 µm) were extracted by combining filtration and ultrafiltration methods. The contents of P, cation and organic carbon in the water-dispersible colloids were determined and the stability and mineral composition of colloidal fractions were characterized. The results showed that Pcoll ranged from 16.5 to 25.5 mg kg-1 and represented 42.8%-64.9% of the water-extracted P in the control. Flooding significantly decreased the Pcoll content by 16.0%-62.1% (mean 32.7%) and it may be attributed to the dissolution of colloidal iron (Fe) bound P. The alternating flooding and drying treatment significantly reduced the Pcoll content by 11.6%-88.0% (mean 67.6%). The Pcoll content of the flooding event was always greater than the Pcoll content of the drying event during flooding and drying cycles. Redundancy analysis and random forest modeling showed that the colloidal calcium (Ca) and ionic strength in soil solutions had negative correlations with the Pcoll content, and pH, ionic strength and truly dissolved P were the critical factors affecting Pcoll. Drying of the flooded soil led to the decrease of pH and the increase of ionic strength, colloidal Ca content and positive charges of colloid surfaces, which promoted colloid aggregation and enhanced soil P sorption capacity. This restricted the loss potential of Pcoll. In summary, controlled flooding and drainage when managed correctly have a role to play in mitigating Pcoll loss from P-enriched calcareous soils.


Asunto(s)
Fósforo , Suelo , Fósforo/análisis , Suelo/química , Agua/química , Inundaciones , Coloides/química
2.
Rheumatol Int ; 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37750894

RESUMEN

We aimed to investigate the factors associated with vitamin D deficiency and changes in 25 (OH)D levels, as well as the impact of those changes on disease activity and renal function among SLE patients. This retrospective cohort study was based on the medical records of SLE patients hospitalized between 2010 and 2021. We collected relevant information from this patient population. Logistic regression analysis was employed to determine the factors associated with vitamin D deficiency and increased 25 (OH)D levels, and we calculated the odds ratios (ORs) and 95% confidence intervals (CIs) accordingly. At baseline, among the 1257 SLE patients, the median and interquartile range of 25 (OH)D levels were 14 (9, 20) ng/ml, with 953 (75.8%) patients exhibiting 25 (OH)D deficiency (< 20 ng/ml). The presence of 25 (OH)D deficiency was found to be associated with renal involvement and a high glucocorticoid (GC) maintenance dose. Among the 383 patients who were followed up for an average of 18 months, an increase of at least 100% in 25 (OH)D levels was positively associated with a decreased GC maintenance dose and vitamin D3 supplementation, with adjusted odds ratios(OR) (95% confidence interval [CI]) of 2.16 (1.02, 4.59) and 1300 (70, 22300), respectively. Furthermore, an increased level of 25 (OH)D was significantly associated with a decrease in the Disease Activity Index 2000 score and the urinary protein/creatinine ratio. Patients with SLE have low vitamin D levels, especially those with impaired kidney function. Increased 25 (OH)D levels can be achieved through supplementation with high doses of vitamin D3 and are associated with improvements in disease activity and the urinary protein/creatinine ratio.

3.
Environ Res ; 229: 115960, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37116675

RESUMEN

Globally, red mud is a solid waste from the aluminum industry, which is rich in iron oxides. It is an effective soil amendment in agriculture that protects connected waters from legacy diffuse phosphorus (P) soil losses. However, other management practices such as flooding and drying and/or organic carbon inputs could potentially alter P fixation in these red mud-amended soils thereby releasing P to waters. The present study was designed and conducted to monitor the mobilization of P in a red mud-amended acidic soil subjected to periodic flooding-drying, straw incorporation, and a mix of both management practices. Sequential extraction and K edge X-ray absorption near-edge structure spectroscopy (k-XANES) were employed to distinguish P fractions/species and the Langmuir model was fitted to evaluate soil P sorption capacity. The content of labile P indicated by CaCl2-P was increased significantly by 101% and 28.7% in the straw incorporation and periodic flooding-drying treatments, while it decreased significantly by 22.3% in the combined periodic flooding-drying with straw incorporation treatment, compared with Control. The inherent phosphate contained in sorghum straw, and the enhanced iron (Fe) reduction and dissolution of Calcium (Ca)-bound P induced by straw addition contributed to mobilization of P in the straw incorporation treatment. In contrast, the increased poorly crystalline Al/Fe oxides-bound P and occluded Fe-bound P fraction in the combined periodic flooding-drying with straw incorporation treatment explains the decrease in CaCl2-P. Furthermore, the increased soil P sorption capacity and the decreased P desorption rate were also responsible for the reduced P loss risk in the treatment. The results of structural equation modelling (SEM) indicated that organically complexed Fe and Fe-bound P were directly affecting P mobilization in the amended soil. Overall, the present study shows that appropriate flooding-drying events coupled with straw incorporation could be a mitigation practice for stabilizing P in red mud-amended soil. However, before it can be applied on a wide scale, multi-point and field trials should be carried out to further evaluate actual environmental implications.


Asunto(s)
Contaminantes del Suelo , Suelo , Suelo/química , Fósforo , Cloruro de Calcio , Óxidos , Contaminantes del Suelo/análisis , Hierro
4.
Water Res ; 236: 119937, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37054612

RESUMEN

Long-term anthropogenic nitrogen (N) and phosphorus (P) inputs have led to lake eutrophication and decreased environmental quality. However, the imbalance in nutrient cycling caused by ecosystem transformation during lake eutrophication is still unclear. The N, P, organic matter (OM) and their extractable forms in the sediment core of Dianchi Lake were investigated. Combining ecological data and geochronological techniques, a coupling relationship between the evolution of lake ecosystems and nutrient retention was established. The results show that the evolution of lake ecosystems promotes the accumulation and mobilization of N and P in sediments, leading to an imbalance in nutrient cycling in the lake system. From the "macrophyte-dominated" period to the "algae-dominated" period, the accumulation rates of potential mobile N and P (PMN, PMP) in sediments have significantly increased, and the retention efficiency of total N and P (TN, TP) has decreased. The increased TN/TP ratio (5.38 ± 1.52 ‒ 10.19 ± 2.94) and PMN/PMP ratio (4.34 ± 0.41 ‒ 8.85 ± 4.16), as well as the reduced humic-like/protein-like ratio (H/P, 11.18 ± 4.43 ‒ 5.97 ± 3.67), indicated an imbalance in nutrient retention during sedimentary diagenesis. Our results show that eutrophication has resulted in the potential mobilization of N in sediments exceeding P, providing new insights for further understanding the nutrient cycle in the lake system and strengthening lake management.


Asunto(s)
Monitoreo del Ambiente , Lagos , Monitoreo del Ambiente/métodos , Ecosistema , Sedimentos Geológicos , Eutrofización , Nutrientes , Fósforo/análisis , Nitrógeno/análisis , China
5.
J Environ Manage ; 339: 117800, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37030239

RESUMEN

The use of calcined sediments (CS) for thin-layer capping is an environment-friendly technology for controlling nitrogen (N) or phosphorus (P) release. However, the effects of CS derived materials and efficiency in controlling the sedimentary N/P ratio have not been thoroughly investigated. While zeolite-based materials have been proven efficient to remove ammonia, it is limited by the low adsorption capacity of PO43-. Herein, CS co-modified with zeolite and hydrophilic organic matter (HIM) was synthesized to simultaneously immobilize ammonium-N (NH4+-N) and remove P, due to the superior ecological security of natural HIM. Studies on the influences of calcination temperature and composition ratio indicated that 600 °C and 40% zeolite were the optimal parameters leading to the highest adsorption capacity and lowest equilibrium concentration. Compared with doping with polyaluminum chloride, doping with HIM not only enhanced P removal but also achieved higher NH4+-N immobilization efficacy. The efficiency of zeolite/CS/HIM capping and amendment in prohibiting the discharge of N/P from sediments was assessed via simulation experiments, and the relevant control mechanism was studied at the molecular level. The results indicated that zeolite/CS/HIM can reduce 49.98% and 72.27% of the N flux and 32.10% and 76.47% of the P flux in slightly and highly polluted sediments, respectively. Capping and incubation with zeolite/CS/HIM simultaneously resulted in substantial reductions in NH4+-N and dissolved total P in overlying water and pore water. Chemical state analysis indicated that HIM enhanced the NH4+-N adsorption ability of CS owing to its abundant carbonyl groups and indirectly increased P adsorption by protonating mineral surface groups. This research provides a novel strategy to control sedimentary nutrient release by adopting an efficient and ecologically secure remediation method to rehabilitate eutrophic lake systems.


Asunto(s)
Contaminantes Químicos del Agua , Zeolitas , Amoníaco/análisis , Zeolitas/química , Sedimentos Geológicos/química , Contaminantes Químicos del Agua/química , Fósforo/química , Lagos , Agua/análisis , Nitrógeno/análisis
6.
J Environ Manage ; 330: 117103, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36603249

RESUMEN

Dredged sediments derived from eutrophicated lakes poses hardness of sludge disposal and ecological risks. The proper pretreatment and utilization of dredged sediments presented a challenge. In this study, Dianchi Lake sediments were dredged, thermally treated and utilized as particle capping material in batch experiments. The effects of calcination on phosphorus speciation and sediment-water interface environment as well as P immobility mechanism were predominantly explored. The microstructures and chemical compositions of calcined sediments were investigated, indicating the porosity and mineralization components were greatly enhanced. The fractional analysis of phosphorus revealed that the calcination process reduced the percentage of unsteady phosphorus, transforming into stable inert phosphorus fractions (Al-P, Ca-P and Res-P), respectively, thereby minimized its mobility and eutrophication risk. Interestingly, calcination temperatures of 700 °C and 800 °C resulted in smaller releasing potentials and equilibrium phosphorus concentrations, despite having lower adsorption capacities than 550 °C. Furthermore, the results of redox potential monitoring showed that the thermally treated Dianchi Lake sediments could enhance the redox potential and dissolved oxygen in the surface sediment, indicating the amelioration of interfacial environment. The practical monitoring experiments confirmed the capping depressed the DTP to 0.031 mg L-1. The investigation of this study provided explicit evidence of Ca coupled P and aerobic Fe bound P strengthened the immobilization effects, and the development of sediment calcination demonstrates a promising strategy for alleviating the burden of endogenous pollution and improving aerobic environment, which are of great significance for lake ecological remediation.


Asunto(s)
Fósforo , Contaminantes Químicos del Agua , Fósforo/análisis , Sedimentos Geológicos/química , Contaminantes Químicos del Agua/análisis , Lagos/química , Eutrofización , Monitoreo del Ambiente , China
7.
Environ Pollut ; 314: 120240, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36152715

RESUMEN

Organic phosphorus (Po) plays a very important role in the process of lake eutrophication, but there is still a lack of knowledge about the internal cycle of Po in suspended particulate matter (SPM) dominated by algal debris. In this study, the characterization of bioavailable Po by sequential extraction and enzymatic hydrolysis showed that 45% of extracted TP was Po in SPM of Lake Dianchi, and 43-98% of total Po in H2O, NaHCO3 and NaOH fractions was enzymatically hydrolyzable Po (EHP, H2O-EHP: 31-53%). Importantly, labile monoester P was the main organic form (68%) of EHP, and its potential bioavailability was higher than that of diester P and phytate-like P. According to the estimation of P pools in SPM of the whole lake, the total load of Pi plus EHP in the H2O extract of SPM was 74.9 t and had great potential risk to enhance eutrophication in the lake water environment. Accordingly, reducing the amount of SPM in the water during the algal blooming period is likely to be a necessary measure that can successfully interfere with or block the continuous stress of unhealthy levels of P on the aquatic ecosystem.


Asunto(s)
Lagos , Contaminantes Químicos del Agua , China , Polvo , Ecosistema , Monitoreo del Ambiente , Eutrofización , Sedimentos Geológicos/química , Lagos/química , Material Particulado , Fósforo/análisis , Ácido Fítico , Hidróxido de Sodio , Contaminantes Químicos del Agua/análisis
8.
Chemosphere ; 307(Pt 3): 135903, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35952785

RESUMEN

In the early stage of eutrophication, the coexistence of "grass and algae" in lakes is obvious. Understanding the P sorption-desorption behavior in natural sediments during the ecologically sensitive transition period has important scientific value for predicting the deterioration of lake ecosystems and formulating restoration measures, but the related mechanisms are still unclear. In this study, the analysis results of sedimentary dissolved organic matter (DOM) fractions, extractable Fe (hydr)oxide fractions and P adsorption experiments showed that sedimentary DOM fractions, especially the tyrosine-like protein fractions and microbial humic-like fractions, played a part in determining the EPC0 and Kd values of sediments in the plateau lake environment. The compound effect of amorphous Fe (hydr)oxides and sedimentary OM affected the increase of sedimentary P adsorption. Interestingly, these phenomena were strongly correlated with water depth. Furthermore, the distribution of water depth to aquatic plants indirectly regulated the values of sedimentary EPC0 and Kd. Meanwhile, the ability of submerged plants to control the sedimentary EPC0andKd values will be forced to shift shallowly, thereby forcing a significant reduction of areas with low EPC0 and high Kd values. This not only enhanced the risk of endogenous P release in lakes, but also accelerated the further deterioration of aquatic ecosystems. Therefore, studying the long-term scale changes of sedimentary EPC0 and Kd values can help to understand the duration of the lake ecological transition period and prevent the transitional deterioration of ecosystem.


Asunto(s)
Fósforo , Contaminantes Químicos del Agua , Adsorción , China , Ecosistema , Monitoreo del Ambiente , Eutrofización , Sedimentos Geológicos , Óxidos , Fósforo/análisis , Poaceae , Tirosina , Agua , Contaminantes Químicos del Agua/análisis
9.
Front Pharmacol ; 13: 963506, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36034791

RESUMEN

Objectives: Osteoarthritis (OA) is a joint disease characterized by degeneration of joint cartilage and is a significant cause of severe joint pain, physical disability, and impaired quality of life in the aging population. Celastrol, a Chinese herbal medicine, has attracted wide interests because of its anti-inflammatory effects on a variety of diseases. This study aimed to investigate the effect of celastrol on OA as well as the mechanisms in vivo and in vitro. Methods: A rat knee OA model was established using "medial collateral ligament transection (MCLT) + partial meniscectomy (pMMT)". Eight weeks after surgery, the OA rats started to receive intra-articular injection of celastrol (1 mg/kg) once a week. Safranin O-fast green (S&F) and hematoxylin and eosin (H&E) staining were used to estimate histopathological changes. Micro-CT was used to evaluate bone volume of the subchondral bone of the knee joint. Chondrocytes were isolated from the knee cartilage of rats and OA patients. Enzyme linked immunosorbent assay (ELISA), Western Blot (WB), Polymerase Chain Reaction (PCR), and Immunohistochemistry (IHC) were used to detect the expression of inflammatory factors and stromal proteins, respectively. Results: We found that celastrol treatment significantly delayed the progression of cartilage damage with a significant reduction in osteophyte formation and bone resorption in OA rat model. In IL-1ß-stimulated rat chondrocytes, celastrol significantly suppressed the production of inflammatory factors such as cyclooxygenase-2 (COX2), interleukin-6 (IL-6), and prostaglandin E2 (PEG2), and reduced IL-1ß-induced matrix degradation by down-regulating the expression of matrix metalloproteinase 13 (MMP13). In addition, we found that toll-like receptor 2 (TLR2) was up-regulated in OA patients and rat knee OA models, while celastrol inhibited TLR2 signal and its downstream nuclear factor-kappa B (NF-κB) phosphorylation. Conclusion: In summary, celastrol may improve OA by inhibiting the TLR2/NF-κB signaling pathway, which provides innovative strategies for the treatment of OA.

10.
Water Res ; 219: 118550, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35567845

RESUMEN

Shallow lakes are more susceptible to eutrophication than deep lakes. The geochemical and biogeochemical mechanisms controlling the vulnerability to eutrophication for deep lakes and shallow lakes remain unknown. Therefore, we investigated the combined Phosphorus (P) retention mechanism with P fractions, water depth, distribution of P-binding metal elements, and macrophytes coverage in a degrading ecosystem of Erhai Lake. We concluded that different mechanisms control the P retention in deep-water areas and shallow-water areas. In shallow areas covered by macrophytes, the biogeochemical process manipulates the P retention by changing the total organic carbon (TOC), calcium (Ca) distributions and turbulence. In deep areas without macrophyte coverage, the aluminum (Al) and iron (Fe) distributions control the P retention by a physicochemical process. Manganese (Mn) was found to be a potential proxy in tracking the kinetic release and readsorb of redox-sensitive P (BD-P) in deep areas. The historical record and core sample indicate that the hydrological engineering induced water depth variation is a vital factor changing the ecosystem of Erhai Lake by forming a large area of intermediate area where macrophytes could only survive at low water level. The uplift of water level in the 1990s gradually changed the ecosystem of Erhai Lake from macrophyte-dominated to algal-macrophyte concomitant that reduced the accumulation of stable P fractions and their binding metals. Macrophytes were capable to preserve P in biomass in the macrophyte-dominated ecosystem, which released 150% and 72% of more labile organic P (NaOH25-nrP) and BD-P in the sediment after the deterioration than before, respectively. Therefore, water depth is a prerequisite to restoring the P preservation capacity of sediment and the macrophyte ecosystem. Further hydraulic engineering projects should consider the effect of water-level-variation-induced ecosystem transition.


Asunto(s)
Ecosistema , Fósforo , China , Eutrofización , Sedimentos Geológicos , Lagos , Metales , Fósforo/análisis , Agua
11.
Environ Pollut ; 305: 119275, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35413405

RESUMEN

Sedimentary nitrogen (N) in lakes significantly influenced by eutrophication plays a detrimental role on the ecological sustainability of aquatic ecosystems. Here, we conducted a thorough analysis of the importance of N potentially released from sediments during the shift of "grass-algae" ecosystem in plateau lakes. From 1964 to 2013, the average total amount of sedimentary potential mineralizable organic nitrogen (PMON) and exchangeable N in whole Lake Dianchi were 5.50 × 103 t and 3.44 × 103 t, respectively. NH4+-N was the main product (>90%) of sedimentary PMON mineralization. The PMON in sediments had great release potential, which tended to regulate the distribution of aquatic plants and phytoplankton in Lake Dianchi and facilitated the replacement of dominant populations. Moreover, NH4+-N produced by sedimentary PMON mineralization and exchangeable NH4+-N have increased the difficulty and complexity of ecological restoration in Lake Dianchi to a certain extent. This study highlights the importance of sedimentary N in lake ecosystem degradation, showing the urgent need to reduce the continuous eutrophication of lakes and restore the water ecology.


Asunto(s)
Ecosistema , Lagos , Amoníaco , China , Eutrofización , Sedimentos Geológicos , Nitrógeno/análisis , Fósforo/análisis
12.
Se Pu ; 40(5): 488-495, 2022 May 08.
Artículo en Chino | MEDLINE | ID: mdl-35478008

RESUMEN

In the field of oil and gas exploration and development, the quick identification of reservoir crude oil properties has a guiding significance for engineers and technicians. Geochemical logging technology is a conventional method to evaluate the properties of crude oil in reservoirs, and it can provide professional knowledge for comprehensive evaluation of reservoirs. In this study, the principles of rock pyrolysis and gas chromatographic analyses in geochemical logging are studied. Moreover, a new method for quantitative analysis of crude oil density by chromatogram is proposed. Combined with the division standard of crude oil property density, the properties of reservoir crude oil can be quickly evaluated. In the experiment, first, the chromatogram was standardized and normalized using computer image processing software. The curve characteristic law of rock pyrolysis gas chromatogram was analyzed, and the corresponding characteristic parameter extraction method was proposed. The chromatogram was converted into a characteristic parameter matrix. Second, three types of artificial intelligence prediction and classification models were studied. The latest meta-heuristic optimization algorithm (sparrow search optimization algorithm) was used to optimize the hyperparameters of the generalized regression neural network, and the accuracy and convergence speed of the model were improved. To study the influence of different positions of rock samples on the experimental results, two groups of samples were utilized: cuttings samples and wall core samples. Based on a comprehensive comparison of the prediction results of the three models, it was found that the generalized regression neural network prediction model optimized by sparrow search algorithm provided the best effect, being a stable model, with small prediction density error, and strong generalization ability. The prediction error coincidence rate (absolute error < 0.02) of this model for cuttings and wall core samples was 95% and 100%, respectively. The root mean square errors were 0.0079 and 0.0069 respectively. The classification accuracy of crude oil properties was 95%. The analysis of the two groups of parallel experimental data indicated that the rock samples from the wall center can more accurately reflect the crude oil properties of the reservoir. Therefore, the method proposed in this study can provide reliable data support for reservoir comprehensive evaluation and on-site construction.


Asunto(s)
Petróleo , Algoritmos , Inteligencia Artificial , Cromatografía de Gases , Redes Neurales de la Computación
13.
Zhongguo Zhen Jiu ; 41(11): 1283-90, 2021 Nov 12.
Artículo en Chino | MEDLINE | ID: mdl-34762385

RESUMEN

By searching the randomized controlled trials (RCTs) of acupuncture and moxibustion from CNKI since its inception date to december 31 of 2019, the development status and hot trend of RCTs of acupuncture and moxibustion in China were summarized. The CiteSpace and VOSviewer software were used to perform keyword co-occurrence analysis, clustering analysis, time-zone analysis and citation-burst analysis, and visual map was drawn. As a result, a total of 60 995 articles were included, which were published in 1027 academic journals with 1787 keywords. The publication date was from 1975 to 2019. During the past 45 years, the publications of RCTs on acupuncture and moxibustion had shown an overall growth trend with characteristics of the times. The RCTs of manual acupuncture ranked the top, and its proportion of publications every 5 years was stable in the past 30 years. Since 1994, the hot words such as electroacupuncture, warming needling, auricular point sticking and various acupoint therapies had emerged; meanwhile, the spectrum of diseases had broadened, and an evolutionary trend corresponding to therapies and disease systems had been formed. In recent decade, the RCTs using moxibustion therapy have increased significantly, and the hot words such as "sub-health" "winter diseases being treated in summer" and "acupoint application/ moxibustion during the dog days" had indicated that acupuncture clinical research was further inclined to the field of chronic disease prevention and health services, which was in line with social development and the needs of the times.


Asunto(s)
Terapia por Acupuntura , Acupuntura , Moxibustión , Puntos de Acupuntura , Ensayos Clínicos Controlados Aleatorios como Asunto
14.
Water Res ; 204: 117604, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34517265

RESUMEN

With the transformation of lake ecosystem from "clear water" to "turbid water", the residual phosphorus (P) accumulated in sediments may slow down the process of aquatic ecological restoration, and the related mechanisms are complex and need to be better understood. In this study, high-resolution systematic investigation and analysis of P-binding forms in the sediments showed that Lake Dianchi, the largest plateau lake in Southwest China, was enriched with NaOH-rP, HCl-P and Res-P, but depleted in NH4Cl-P, BD-P and NaOH-nrP. The BD-P, NaOH-nrP and NaOH-rP were the main contributors to potential P release from sediments, while the release potential of NH4Cl-P was relatively weak (<1%). When the external P loading gradually decreased, the internal P loading of Lake Dianchi was estimated to be 522 mg P/(m2•a) in the past 30 years. The succession of "grass-algae" type in Lake Dianchi coincided with reduced absorption and transformation of potential mobile P and decreased accumulation of stable P, especially the Res-P. Meanwhile, the temporal variation of potential mobile P was a good predictor of ecological degradation and reduced ecosystem sustainability in Lake Dianchi.


Asunto(s)
Lagos , Poaceae , Ecosistema , Fósforo , Agua
15.
Int J Hyperthermia ; 38(1): 13-21, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33491511

RESUMEN

Aim: Magnetic hydrogels (MHGs) have been proposed to avoid the redistribution and loss of magnetic nanoparticles (MNPs) when administrated by intratumoral injection. However, the requirement of complex cooling systems and temperature monitoring systems still hinder the clinical application of MHGs. This study investigates the feasibility of developing an MHG to realize the self-regulation of hyperthermia temperature. Methods: The MHG was developed by dispersing the MNPs with self-regulating temperature property into the temperature-sensitive hydrogel through physical crosslinking. The MHG's gelation temperature was tested by measuring the storage modulus and loss modulus on a rotational rheometer. The biocompatibility of the MHG and MNPs was characterized by CCK-8 assay against HaCaT cells. The in vivo magnetic heating property was examined through monitoring the temperature in the MHG on mice back upon the application of the alternating magnetic field (400 ± 5 Oe, 100 ± 5 kHz) every week for successive six weeks. Results: The gelation temperature of the MHG falls in 28.4°C-37.4°C. At in vivo applied concentration of 80 mg/mL, the MHG exhibits over 80% cell viability after 72 h, significantly higher than 50% cell viability of the MNPs (p<0.001). The MHG's stable magnetic hyperthermia temperatures in vivo are in the range of 43.4°C-43.8°C. Conclusions: The developed MHG can be injected using a syringe and will solidify upon body temperature. The biocompatibility is improved after the MNPs being made into MHG. The MHG can self-regulate the temperature for six weeks, exhibiting application potential for self-regulating temperature hyperthermia.


Asunto(s)
Hipertermia Inducida , Nanopartículas de Magnetita , Animales , Hidrogeles , Hipertermia , Campos Magnéticos , Ratones , Temperatura
16.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 36(4): 434-6, 2016 Apr.
Artículo en Chino | MEDLINE | ID: mdl-27323615

RESUMEN

OBJECTIVE: To observe effects of Ligustrazine on serum S100p protein and neuron-specific enolase (NSE) in elderly patients undergoing orthopedics operations. METHODS: Totally 60 patients undergoing selective total hip replacement, 65-80 years old, who were in line with American Society of Anesthesiologists (ASA) grade I or II, were randomly assigned to the Ligustrazine group (Group L) and the normal saline control group (Group S). The right internal jugular vein catheters were placedcephalad and ensured theirs tips in jugular venous bulbs after anesthesia induction and tracheal intubation. Patients in Group L received 2 mg/kg Ligustrazine Injection (40 drops within one minute) and those inGroup S received equal volume of normal saline via central veins before operations. Other medicines were the same for all patients during and after operation. Five millimeter blood sample was collected frominternal jugular venous bulbs before operation (T0), 24 h (T1), 72 h (T2), 168 h (7th day, T3) after operation. Serum was collected after centrifuge. S100ß protein and NSE concentration were analyzed usingELISA. Mini-mental state examinations (MMSE) were scored by the same doctor at T0, T1, T2, and T3,respectively. RESULTS: There was no statistical difference in MMSE scores, serum S1000 protein, or NSE at TO (P > 0.05). Compared with TO, S100 P protein and NSE concentration increased and MMSE scores decreased at T1, T2, and T3 in the two groups. All indices except S100P protein and NSE at T3 were statistically different between Group L and Group S (P < 0.05). CONCLUSION: Serum S100P protein and NSE could be changed by pre-operation injecting Ligustrazine at certain dose in elderly patients undergoing orthopedics operations.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Fosfopiruvato Hidratasa/sangre , Pirazinas/uso terapéutico , Subunidad beta de la Proteína de Unión al Calcio S100/sangre , Anciano , Anciano de 80 o más Años , Humanos
17.
Huan Jing Ke Xue ; 37(10): 3828-3834, 2016 Oct 08.
Artículo en Chino | MEDLINE | ID: mdl-29964415

RESUMEN

In order to reveal the effect of aquatic plants distribution on the mass concentration of phosphorus in sediment interstitial water, the mass concentrations of Dissolved Total Phosphorus (DTP), Soluble Reactive Phosphorus (SRP) and Dissolved Organic Phosphorus (DOP) in the sediment interstitial water and overlying water from areas with or without plants in the same site of Dianchi were studied. The vertical variation characteristics of phosphorus forms in sediment interstitial water were analyzed to explore the effect of aquatic plants on the phosphorus forms in sediment interstitial water. The results showed: ①Aquatic plants had an significant effect on the phosphorus mass concentration of the sediment interstitial water in different Dianchi lakes. However, they varied with different distribution sites and depth. ②Aquatic plants significantly decreased the percentage of DOP contribution in the sediment interstitial water. The average contribution of DOP with aquatic plants was 32.87%, while that without plants reached 57.68%; ③Aquatic plants significantly inhibited the release of inorganic phosphorus in sediments and promoted the transformation of DOP. The SRP diffusion flux at sediment-water interface with aquatic plants was increased by 39.99% as compared with that without plants; ④The growth of aquatic plants significantly reduced the concentration of phosphorus in sediment interstitial water, especially DOP, and the reduction rate of the sediment interstitial water DOP was from 38.02% to 85.49%. Therefore, the analysis of the contribution and reduction rate of aquatic plants on the sediment interstitial water DOP was of great importance in understanding the relationship between aquatic plants and DOP, as well as the mineralization of organic phosphorus in sediments.


Asunto(s)
Sedimentos Geológicos/química , Lagos , Fósforo/análisis , Plantas , Contaminantes Químicos del Agua/análisis , China , Agua
18.
BMC Musculoskelet Disord ; 12: 215, 2011 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-21958301

RESUMEN

BACKGROUND: Pulsed electromagnetic fields (PEMF) stimulation has been used successfully to treat nonunion fractures and femoral head osteonecrosis, but relatively little is known about its effects on preventing steroid-induced osteonecrosis. The purpose of the study was to investigate the effects of PEMF stimulation on the prevention of steroid-induced osteonecrosis in rats and explore the underlying mechanisms. METHODS: Seventy-two male adult Wistar rats were divided into three groups and treated as follows. (1) PEMF stimulation group (PEMF group, n = 24): intravenously injected with lipopolysaccharide (LPS, 10 µg/kg) on day 0 and intramuscularly injected with methylprednisolone acetate (MPSL, 20 mg/kg) on days 1, 2 and 3, then subjected to PEMF stimulation 4 h per day for 1 to 8 weeks. (2) Methylprednisolone-treated group (MPSL group, n = 24): injected the same dose of LPS and MPSL as the PEMF group but without exposure to PEMF. (3) Control group (PS group, n = 24): injected 0.9% saline in the same mode at the same time points. The incidence of osteonecrosis, serum lipid levels and the mRNA and protein expression of transforming growth factor ß1 (TGF-ß1) in the proximal femur were measured 1, 2, 4 and 8 weeks after the last MPSL (or saline) injection. RESULTS: The incidence of osteonecrosis in the PEMF group (29%) was significantly lower than that observed in the MPSL group (75%), while no osteonecrosis was observed in the PS group. The serum lipid levels were significantly lower in the PEMF and PS groups than in the MPSL group. Compared with the MPSL and PS groups, the mRNA expression of TGF-ß1 increased, reaching a peak 1 week after PEMF treatment, and remained high for 4 weeks, then declined at 8 weeks, whereas the protein expression of TGF-ß1 increased, reaching a peak at 2 weeks after PEMF treatment, and remained high for 8 weeks. CONCLUSIONS: PEMF stimulation can prevent steroid-induced osteonecrosis in rats, and the underlying mechanisms involve decreased serum lipid levels and increased expression of TGF-ß1.


Asunto(s)
Campos Electromagnéticos , Magnetoterapia/métodos , Osteonecrosis/radioterapia , Animales , Modelos Animales de Enfermedad , Expresión Génica/efectos de la radiación , Glucocorticoides/farmacología , Inyecciones Intravenosas , Lípidos/sangre , Lipopolisacáridos/farmacología , Masculino , Metilprednisolona/análogos & derivados , Metilprednisolona/farmacología , Acetato de Metilprednisolona , Osteonecrosis/inducido químicamente , Osteonecrosis/metabolismo , Tratamiento de Radiofrecuencia Pulsada , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Factor de Crecimiento Transformador beta1/genética , Factor de Crecimiento Transformador beta1/metabolismo
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