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1.
Clin Proteomics ; 20(1): 35, 2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37689639

RESUMO

OBJECTIVE: Lymph node metastasis (LNM) and lymphatic vasculature space infiltration (LVSI) in cervical cancer patients indicate a poor prognosis, but satisfactory methods for diagnosing these phenotypes are lacking. This study aimed to find new effective plasma biomarkers of LNM and LVSI as well as possible mechanisms underlying LNM and LVSI through data-independent acquisition (DIA) proteome sequencing. METHODS: A total of 20 cervical cancer plasma samples, including 7 LNM-/LVSI-(NC), 4 LNM-/LVSI + (LVSI) and 9 LNM + /LVSI + (LNM) samples from a cohort, were subjected to DIA to identify differentially expressed proteins (DEPs) for LVSI and LNM. Subsequently, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed for DEP functional annotation. Protein-protein interaction (PPI) and weighted gene coexpression network analysis (WGCNA) were used to detect new effective plasma biomarkers and possible mechanisms. RESULTS: A total of 79 DEPs were identified in the cohort. GO and KEGG analyses showed that DEPs were mainly enriched in the complement and coagulation pathway, lipid and atherosclerosis pathway, HIF-1 signal transduction pathway and phagosome and autophagy. WGCNA showed that the enrichment of the green module differed greatly between groups. Six interesting core DEPs (SPARC, HPX, VCAM1, TFRC, ERN1 and APMAP) were confirmed to be potential plasma diagnostic markers for LVSI and LNM in cervical cancer patients. CONCLUSION: Proteomic signatures developed in this study reflected the potential plasma diagnostic markers and new possible pathogenesis mechanisms in the LVSI and LNM of cervical cancer.

2.
J Environ Manage ; 340: 118002, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37119631

RESUMO

Water diverted from rivers for irrigation areas often contains large amounts of nitrogen (N), which is frequently overlooked and its role in contributing to N pollution is unknown. To investigate the influence of water diversion on N in different systems within irrigation areas, we developed and optimized the N footprint model, taking into account the N carried by irrigation water diversion and drainage in irrigated areas. This optimized model can serve as a reference for evaluating N pollution in other irrigated areas. By analyzing 29 years (1991-2019) of statistical data from a diverted irrigation area in Ningxia Hui Autonomous Region (Ningxia), China, the study assessed the contribution of water diversion to N in agriculture, animal husbandry, and human domestic activities. The results demonstrated that water diversion and drainage accounted for 10.3% and 13.8% in whole system, of the total N input and output in Ningxia, highlighting the potential N pollution risks associated with these activities. Additionally, the use of fertilizers in the plant subsystem, feed in the animal subsystem, and sanitary sewage in the human subsystem represented the main sources of N pollution in each subsystem. On a temporal scale, the study found that N loss increased year by year before reaching a stable level, indicating that N loss had reached its peak in Ningxia. The correlation analysis suggested that rainfall could regulate N input and output in irrigated areas by showing a negative correlation with water diversion, agricultural water consumption, and N from irrigated areas. Moreover, the study revealed that the amount of N brought by water diverted from rivers for irrigation should be taken into account when calculating the amount of fertilizer N required in the irrigation area.


Assuntos
Irrigação Agrícola , Nitrogênio , Humanos , Animais , Nitrogênio/análise , Irrigação Agrícola/métodos , Poluição Ambiental/análise , Agricultura/métodos , Água/análise , China , Fertilizantes/análise
3.
Front Bioeng Biotechnol ; 10: 1053679, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36338115

RESUMO

Background: Recent studies have reported that the incidence of sensitive skin is increasing. Skin sensitivity and skin barrier functions were related to many skin diseases including atopic dermatitis, psoriasis, rosacea, and so on. Mesenchymal stem cell (MSC)-derived exosomes (hMSC) might be considered as a new effective therapeutic scheme. Aims: This study aims to investigate the safety and efficacy of hMSC exosomes as a novel topical treatment for sensitive skin. Patients/Methods: Exosomes were extracted from primary hMSC via ultracentrifugation method. The morphology of hMSC exosomes was studied via transmission electron microscope. Expression of exosome specific surface marker was detected via Western blot. 22 subjects (female, aged 18-55) diagnosed with sensitive skin were enrolled. Follow-up was conducted before, 7-day, 14-day, and 28-day after hMSC exosomes use. Transepidermal water loss (TEWL), surface hydration, sebum secretion, and L*a*b* value were simultaneously tested at the same time point in an environment-controlled room. Results: Under transmission electron microscopy, the extracted hMSC exosomes were circular or elliptical with intact membrane structure, and their diameters ranged mainly from 40 to 80 nm. Western blot showed that the expression of markers CD63, CD9, and Tsg101 was positive. Brownian motion based nanoparticle trajectory analysis (NTA) showed that the main peak of particle size distribution occurred around 96 nm, the average particle size was 122 nm, and the main peak accounted for 96.7%. All this conformed to the biological characteristics of exosomes standardized by the International Society for Extracellular Vesicles. In the clinical trial, scores of objective symptoms including roughness, scales, erythema, and subjective symptoms including tension, burning, or itching, were improved after 7-, 14-, and 28- day using hMSC-exosomes. TEWL, hydration, sebum, pH, and a* values were tended to return to the level of healthy skin. Conclusion: The hMSC-exosomes, with the advantages of biocompatibility and biodegradability, could improve clinical symptoms and eruptions in sensitive skin patients, and might be as an MSC cell-free novel therapy in sensitive skin-related disease treatment.

4.
Bioorg Chem ; 128: 106116, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36063753

RESUMO

Carnosic acid could disrupt the ß-catenin/BCL9 protein-protein interaction and inhibit ß-catenin dependent transcription, thereby reduce the incidence of colorectal cancer induced by abnormal activation of Wnt/ß-catenin signalling pathway. However, its activity was weak (IC50 for SW480: 28.2 ± 2.05 µM) and total synthesis was difficult. During the structural simplification of natural products, S0 was revealed to be the basic pharmacophore of carnosic acid. Subsequent structural optimization of S0 led to the discovery of S11 as a possible anticancer agent with prominent proliferation inhibition effect (IC50 for SW480: 9.56 ± 0.91 µM) and best selectivity index (SI = 3.0) against Wnt hyperactive cancer cells. Futher mechanism investigation through TOP/FOP dual luciferase reporter assay, immunofluorescence, co-immunoprecipitation, microscale thermophoresis, downstream oncoprotein expression and cell apoptosis showed that compound S11 could significantly inhibit the proliferation of SW480 cells via obvioudsly decreasing the nucleus translocation of ß-catenin and effectively disrupting ß-catenin/BCL9 protein-protein interaction. Additionally, cell migration, molecule docking, in vitro stability and solubility assays were also conducted. Overall, S11 was worthy of in-depth study as a potential inhibitor for the Wnt/ß-catenin pathway and its discovery also proved that the structural simplification of natural products was still one of the effective methods to find new lead compounds or candidate drugs.


Assuntos
Produtos Biológicos , beta Catenina , Androstenóis , Produtos Biológicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Hidroxibenzoatos , Via de Sinalização Wnt , beta Catenina/metabolismo
5.
Sci Total Environ ; 805: 150441, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34818792

RESUMO

Excess phosphorus (P) leached from high fertiliser input cropping systems in northern China is having detrimental effects on water quality. Before improved management can be directed at specific soils and cropping system types estimates of P leached loss apportionment and mitigation potentials across the main soil (fluvo-aquic soil, FAS; cinnamon soil, CS; black soil, BS) areas and cropping systems (protected vegetable fields, PVFs; open vegetable fields, OVFs; cereal fields, CFs) are needed. The present study designed and implemented conventional fertilisation and low input system trials at 75 sites inclusive of these main soils and cropping system types in northern China. At all sites, a uniform lysimeter design (to 0.9 m depth) enabled the collection and analysis of leachate samples from 7578 individual events between 2008 and 2018. In addition, site-specific static and dynamic activity data were recorded. Results showed that annual total phosphorus (TP) leached losses across the main soil areas and cropping systems were 4.99 × 106 kg in northern China. A major finding was PVFs contributed to 48.5% of the TP leached losses but only accounted for 5.7% of the total cropping areas. The CFs and OVFs accounted for 40.3% and 11.2% of the TP leached losses, respectively. Across northern China, the TP leached losses in PVFs and OVFs were greatest in FAS areas followed by CS and BS areas. The higher TP leached losses in FAS areas were closely correlated with greater P fertiliser inputs and irrigation practices. From a management perspective in PVFs and OVFs systems, a decrease of P inputs by 10-30% would not negatively affect yields while protecting water quality. The present study highlights the importance of decreasing P inputs in PVFs and OVFs and supporting soil P nutrient advocacy for farmers in China.


Assuntos
Fósforo , Solo , Agricultura , China , Fertilizantes/análise , Nitrogênio/análise , Fósforo/análise , Verduras , Qualidade da Água
6.
Environ Pollut ; 266(Pt 2): 115304, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32805596

RESUMO

The excessive application of manure has caused a high load of phosphorus (P) in the North China Plain. Having an understanding of how manure application affects soil P changes and its transport between different soil layers is crucial to reasonably apply manure P and reduce the associated loss. Based on our 28-year field experiments, the compositions and changes of P species and the risk of P loss under excessive manure treatments were investigated, i.e., no fertilizer (CK), mineral fertilizer NPK (NPK), NPK plus 22.5 t ha-1 yr-1 swine manure (LMNPK), and NPK plus 33.75 t ha-1 yr-1 swine manure (HMNPK). Manure application increased the content of orthophosphate and myo-inositol hexaphosphate (myo-IHP), especially the orthophosphate content exceeded 95%. The amount of orthophosphate in manure and the conversion of organic P to inorganic P in soil were the main reasons for the increased soil orthophosphate. Compared with NPK treatment, soil microbial biomass phosphorus and alkaline phosphatase activity in LMNPK and HMNPK treatments significantly increased. Compared with NPK treatment, a high manure application rate under HMNPK treatment could increase the abundance of organic P-mineralization gene phoD by 60.0% and decrease the abundance of inorganic P-solubilization gene pqqC by 45.9%. Due to the continuous additional manure application, soil P stocks significantly increased under LMNPK and HMNPK treatments. Furthermore, part of the P has been leached to the 60-80 cm soil layer. Segmented regression analysis indicated that CaCl2-P increased sharply when Olsen-P was higher than 25.1 mg kg-1, however the content of Olsen-P did not exceed this value until 10 years after consecutive excessive manure application. In order to improve soil P availability and decrease the risk of P loss, the manure application rate should vary over time based on soil physicochemical conditions, plants requirements, and P stocks from previous years.


Assuntos
Esterco , Solo , Agricultura , Animais , China , Fertilizantes , Nitrogênio/análise , Fósforo/análise , Suínos
7.
Biomed Pharmacother ; 130: 110537, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32717630

RESUMO

Rhizoma Bletillae, the tubes of Bletilla striata, has been traditionally used in China as a hemostatic agent. In preliminary studies, the major active fraction responsible for its hemostatic effect have been confirmed to be Rhizoma Bletillae polysaccharide (RBp), but the hemostatic mechanism of action of RBp is still unknown.The main aim of this study was to clarify its mechanism of hemostatic effect. RBp was prepared by 80 % ethanol precipitation of the water extract of Rhizoma Bletillae followed by the Sevag method to remove proteins. The average molecular weight (Mw) of the crude RBp maintained at a range of 30.06-200 KDa. The hemostatic effects of RBp were evaluated by testing its effect on the platelet aggregation of rat platelet-rich plasma (PRP). PRP was dealt with different concentrations of RBp and platelet aggregation was measured by the turbidimetric method. The hemostatic mechanism of RBp was investigated by examining its effect on platelet shape, platelet secretion, and activation of related receptors (P2Y1, P2Y12 and TXA2) by electron microscopy and the turbidimetric method. RBp significantly enhanced the platelet aggregations at concentrations of 50-200 mg/L in a concentration-dependent manner. The inhibitory rate of platelet aggregation was significantly increased by apyrase and Ro31-8220 in a concentration-dependent manner, while RBp-induced platelet aggregation was completely inhibited by P2Y1, P2Y12 and the PKC receptor antagonists. However, the aggregation was not sensitive to TXA2. RBp, the active ingredients of Rhizoma Bletillae responsible for its hemostatic effect, could significantly accelerate the platelet aggregation and shape change. The hemostatic mechanism may involve activation of the P2Y1, P2Y12, and PKC receptors in the adenosine diphosphate (ADP) receptor signaling pathway.


Assuntos
Hemostáticos/farmacologia , Plasma Rico em Plaquetas/efeitos dos fármacos , Polissacarídeos/farmacologia , Receptores Purinérgicos P2/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Técnicas In Vitro , Peso Molecular , Extratos Vegetais/farmacologia , Tubérculos/química , Agregação Plaquetária/efeitos dos fármacos , Proteína Quinase C/efeitos dos fármacos , Ratos , Receptores Purinérgicos P2Y1/efeitos dos fármacos , Receptores Purinérgicos P2Y12/efeitos dos fármacos
8.
Water Res ; 177: 115767, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32283435

RESUMO

The curve number (CN) method developed by the United States Department of Agriculture (USDA) in 1954 is the most common adopted method to estimate surface runoff. For years, applicability of the CN method is a conundrum when implementing to other countries. Specifically, countries with more complex natural environment may require more dedicated adjustments. Therefore, the current CN look-up table provided by USDA might not be appropriate and could be questionable to be applied directly to regions elsewhere. Some studies have been conducted to modify CN values according to specified natural characteristics in scattered regions of mainland China. However, an integral and representative work is still not available to address potential concerns in general matters. In this study, a large set of rainfall-runoff monitoring data were collected to adjust CN values in 55 study sites across China. The results showed that the revised CN values are largely different from CN look-up table provided by USDA, which would lead to huge errors in runoff estimation. In this study, the revised CN (dubbed CN-China) provides better reference guidelines that are suitable for most natural conditions in China. In addition, scientists and engineers from other parts of the world can take advantage of the proposed work to enhance the quality of future programs related to surface runoff estimation.


Assuntos
Chuva , Movimentos da Água , China , Monitoramento Ambiental
9.
Glob Chang Biol ; 26(6): 3356-3367, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32281177

RESUMO

Plastic pollution is a global concern given its prevalence in aquatic and terrestrial ecosystems. Studies have been conducted on the distribution and impact of plastic pollution in marine ecosystems, but little is known on terrestrial ecosystems. Plastic mulch has been widely used to increase crop yields worldwide, yet the impact of plastic residues in cropland soils to soil health and crop production in the long term remained unclear. In this paper, using a global meta-analysis, we found that the use of plastic mulch can indeed increase crop yields on average by 25%-42% in the immediate season due to the increase of soil temperature (+8%) and moisture (+17%). However, the unabated accumulation of film residues in the field negatively impacts its physicochemical properties linked to healthy soil and threatens food production in the long term. It has multiple negative impacts on plant growth including crop yield (at the mean rate of -3% for every additional 100 kg/ha of film residue), plant height (-2%) and root weight (-5%), and soil properties including soil water evaporation capacity (-2%), soil water infiltration rate (-8%), soil organic matter (-0.8%) and soil available phosphorus (-5%) based on meta-regression. Using a nationwide field survey of China, the largest user of plastic mulch worldwide, we found that plastic residue accumulation in cropland soils has reached 550,800 tonnes, with an estimated 6%-10% reduction in cotton yield in some polluted sites based on current level of plastic residue content. Immediate actions should be taken to ensure the recovery of plastic film mulch and limit further increase in film residue loading to maintain the sustainability of these croplands.


Assuntos
Agricultura , Plásticos , China , Produtos Agrícolas , Ecossistema , Abastecimento de Alimentos , Solo
10.
Sci Rep ; 10(1): 5907, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32245982

RESUMO

In the wheat-maize rotation cultivation system in northern China, excessive irrigation and over-fertilization have depleted groundwater and increased nitrogen (N) losses. These problems can be addressed by optimized N fertilization and water-saving irrigation. We evaluated the effects of these practices on greenhouse gas emissions (GHG), net profit, and soil carbon (C) sequestration. We conducted a field experiment with flood irrigation (FN0, 0 kg N ha-1 yr-1, FN600, 600 kg N ha-1 yr-1) and drip fertigation treatments (DN0, 0 kg N ha-1 yr-1; DN420, 420 kg N ha-1 yr-1; DN600, 600 kg N ha-1 yr-1) in 2015-2017. Compared with FN600, DN600 decreased direct GHGs (N2O + CH4) emissions by 21%, and increased the net GHG balance, GHG intensity, irrigation water-use efficiency (IWUE), and soil organic C content (ΔSOC) by 13%, 12%, 88%, and 89.8%, respectively. Higher costs in DN600 (for electricity, labour, polyethylene) led to a 33.8% lower net profit than in FN600. Compared with FN600, DN420 reduced N and irrigation water by 30% and 46%, respectively, which increased partial factor productivity and IWUE (by 49% and 94%, respectively), but DN420 did not affect GHG mitigation or net profit. Because lower profit is the key factor limiting the technical extension of fertigation, financial subsidies should be made available for farmers to install fertigation technology.


Assuntos
Irrigação Agrícola/métodos , Produção Agrícola/métodos , Fertilizantes , Efeito Estufa/prevenção & controle , Óxido Nitroso/metabolismo , Sequestro de Carbono , China , Gases de Efeito Estufa/metabolismo , Nitrogênio/química , Solo/química , Triticum/metabolismo , Zea mays/metabolismo
11.
Sci Total Environ ; 720: 137558, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32135283

RESUMO

The use of livestock manure as a substitution for synthetic nitrogen (N) fertilizers is recommended to improve the sustainable use of manure nutrients and alleviate the adverse impacts of synthetic N fertilizers on the environment. A thorough understanding of how such substitutions affect reactive N losses and greenhouse gas (GHG) emissions in cereal production systems in the North China Plain (a main livestock production region in China), is needed to achieve an environmental friendly and sustainable production. Based on a long-term field experiment, different manure/chemical fertilizer treatments were designed, i.e., non-fertilization control (CK), chemical fertilizers alone (NPK), and manure substitution for chemical N fertilizers (with equivalent N rate; NPKP, 50% N from pig manure; NPKC, 50% N from chicken manure). Crop yield, nitrogen use efficiency (NUE), soil fertility, N losses, and GHG emissions were chosen as prominent indicators to evaluate the consequences of manure substitutions for N-based fertilizers. The replacement of synthetic fertilizers by livestock manure decreased NO3-N leaching and NH3 volatilization by 46.2% and 5.61-22.2%, respectively, while sustained the crop yields and improved NUE. However, both NPKP and NPKC treatments did not have any impact on N2O and CO2 mitigation. Compared with NPK, NPKC and NPKP meaningfully increased SOC by 9.56% and 19.6%, respectively. More specifically, NPKC increased TN content by 14.7% (P < 0.05) compared to NPK treatment. The results showed that 50% substitution of manure for synthetic N fertilizers is a potential option in maize production systems to decrease N losses (including NH3, N2O emissions and N leaching) by approximately 45% (42.8-48.1%). However, only 1.81% of the total farmers surveyed (i.e., 16,595) have being applied livestock manure for maize cultivation in the North China Plain. Therefore, famers in this plain should be encouraged to use manure to improve ecological aspects of cereal cultivation and decrease the associated environmental pollutions.


Assuntos
Esterco , Agricultura , Animais , China , Fertilizantes , Gases de Efeito Estufa , Gado , Nitrogênio , Solo , Suínos , Zea mays
12.
Sci Total Environ ; 714: 136851, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32018984

RESUMO

The net anthropogenic phosphorus inputs (NAPI) model has been used extensively to assess changes in phosphorus (P) inputs and cycling in the environment. However, temporary populations have generally been unconsidered in these assessments. In this study, the NAPI model was used to estimate P loads from the 16 towns and villages in the Erhai Lake Basin (ELB), Southwest China and to evaluate the potential impact from temporary residents (tourism). The results showed that the average value P inputs in the basin (estimated at 2384 kg P km-2 year-1) were 5 times the national average level, and that temporary residents contributed 1%. Agriculture accounted for most of the net P, with chemical fertilizers (55% of the inputs) as the main source, followed by food and animal feed. Only 9.54% of the P inputs to the basin were exported. River water quality and NAPI were significantly correlated (P < 0.01). Tourism industry contributes significantly to regional economic growth and prosperity, but its beneficial effects on the economy does not equate with the adverse impact on environment. This study illustrates what is happening in Southwest China and provides scientific evidence that shows we need to find novel ways to reduce nutrients.

13.
Huan Jing Ke Xue ; 40(12): 5375-5383, 2019 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854609

RESUMO

The runoff formed by rainfall carrying various land surface materials into rivers and lakes is an important factor leading to a change in water quality, and the characteristics of nitrogen and phosphorus output of rivers under different rainfall intensities are different. This study explores the impact of rainfall intensity on the water quality of the Fengyu River Watershed in the plateau agricultural region, based on the water quality monitoring data of the export section of the Fengyu River Watershed from 2011 to 2013, combined with local rainfall monitoring. The effects of four rainfall intensities (light rain, moderate rain, heavy rain, and torrential rain) on the content of different nitrogen and phosphorus components in water were analyzed. The results show that the rainfall intensity has a significant effect on the nitrogen and phosphorus emissions of the Fengyu River Watershed. The average nitrogen and phosphorus concentrations of all components are lower in light rain (<10 mm) and moderate rain (10-25 mm), and higher in heavy rain (25-50 mm) and torrential rain (50-100 mm). The percentage of NH4+-N (57.14%-76.85%) to TN is larger than that of PN (23.15%-42.86%), and the percentage of TDP (22.73%-28.00%) to TP is smaller than that of PP (72.00%-77.27%). The nitrogen concentration of different forms is:TN > NH4+-N > PN; the phosphorus concentration of different forms is:TP > PP > TDP.

14.
PeerJ ; 7: e7738, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31592347

RESUMO

Information on the homogeneity and distribution of 13carbon (13C) and nitrogen (15N) labeling in winter wheat (Triticum aestivum L.) is limited. We conducted a dual labeling experiment to evaluate the variability of 13C and 15N enrichment in aboveground parts of labeled winter wheat plants. Labeling with 13C and 15N was performed on non-nitrogen fertilized (-N) and nitrogen fertilized (+N, 250 kg N ha-1) plants at the elongation and grain filling stages. Aboveground parts of wheat were destructively sampled at 28 days after labeling. As winter wheat growth progressed, δ 13C values of wheat ears increased significantly, whereas those of leaves and stems decreased significantly. At the elongation stage, N addition tended to reduce the aboveground δ 13C values through dilution of C uptake. At the two stages, upper (newly developed) leaves were more highly enriched with 13C compared with that of lower (aged) leaves. Variability between individual wheat plants and among pots at the grain filling stage was smaller than that at the elongation stage, especially for the -N treatment. Compared with those of 13C labeling, differences in 15N excess between aboveground components (leaves and stems) under 15N labeling conditions were much smaller. We conclude that non-N fertilization and labeling at the grain filling stage may produce more uniformly 13C-labeled wheat materials, whereas the materials were more highly 13C-enriched at the elongation stage, although the δ 13C values were more variable. The 15N-enriched straw tissues via urea fertilization were more uniformly labeled at the grain filling stage compared with that at the elongation stage.

15.
Sci Total Environ ; 650(Pt 2): 2251-2259, 2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30292118

RESUMO

The effects of long-term animal manure application and crop straw incorporation on the migration of carbon (C) and nitrogen (N) deep into the soil profile and the associated N leaching risk in particular have not been thoroughly elucidated to date. Soil profile samples were collected from depths of up to 200 cm from the following four treatments in a 27-year field experiment on the North China Plain: N + phosphorus (P) + potassium (K) fertilizers (NPK), NPK + 22.5 t ha-1 swine manure (NPKM), NPK + 33.7 t ha-1 swine manure (NPKM+) and NPK + straw incorporation (NPKS). The results revealed that long-term manure application and straw incorporation significantly enhanced the soil organic C (SOC) and total N (TN) contents in the upper 20 cm and that this effect was weaker in the deeper soil layers (P < 0.05). Residual nitrate-N (NO3--N) contents at 0 to 40 cm and 120 to 200 cm in the NPKM and NPKM+ were 4-16 and 2-9 times higher than those in the NPK and NPKS, respectively. These results indicated a greater potential for N leaching from manure addition and a higher propensity for NO3--N leaching out of the 40-100 cm soil layer. Pearson relationship analysis demonstrated that NO3--N content was clearly affected by SOC and dissolved organic N (DON) contents along the soil profile (20-200 cm), implying that the higher residual NO3--N contents in the deeper soil from manure addition were partially attributable to the mineralization and nitrification of the downward SOC and DON. Interestingly, a low level of residual NO3--N combined with negative mineralization in the 120-200 cm soil layers of the NPKS treatment was observed, suggesting that straw incorporation promotes soil NO3--N retention. Thus, we concluded that long-term manure application is beneficial for soil NO3--N content retention, whereas long-term straw incorporation benefits NO3--N retention.

16.
Sci Total Environ ; 633: 230-239, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29574366

RESUMO

The impacts of manure application on soil ammonia (NH3) volatilization and greenhouse gas (GHG) emissions are of interest for both agronomic and environmental reasons. However, how the swine manure addition affects greenhouse gas and N emissions in North China Plain wheat fields is still unknown. A long-term fertilization experiment was carried out on a maize-wheat rotation system in Northern China (Zea mays L-Triticum aestivum L.) from 1990 to 2017. The experiment included four treatments: (1) No fertilizer (CK), (2) single application of chemical fertilizers (NPK), (3) NPK plus 22.5t/ha swine manure (NPKM), (4) NPK plus 33.7t/ha swine manure (NPKM+). A short-term fertilization experiment was conducted from 2016 to 2017 using the same treatments in a field that had been abandoned for decades. The emissions of NH3 and GHGs were measured during the wheat season from 2016 to 2017. Results showed that after long-term fertilization the wheat yields for NPKM treatment were 7105kg/ha, which were higher than NPK (3880kg/ha) and NPKM+ treatments (5518kg/ha). The wheat yields were similar after short-term fertilization (6098-6887kg/ha). The NH3-N emission factors (EFamm) for NPKM and NPKM+ treatments (1.1 and 1.1-1.4%, respectively) were lower than NPK treatment (2.2%) in both the long and short-term fertilization treatments. In the long- and short-term experiments the nitrous oxide (N2O) emission factors (EFnit) for NPKM+ treatment were 4.2% and 3.7%, respectively, which were higher than for the NPK treatment (3.5% and 2.5%, respectively) and the NPKM treatment (3.6% and 2.2%, respectively). In addition, under long and short-term fertilization, the greenhouse gas intensities for the NPKM+ treatment were 33.7 and 27.0kg CO2-eq/kg yield, respectively, which were higher than for the NPKM treatment (22.8 and 21.1kg CO2-eq/kg yield, respectively). These results imply that excessive swine manure application does not increase yield but increases GHG emissions.

17.
Sci Total Environ ; 618: 1173-1183, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29054672

RESUMO

Optimizing the nitrogen (N) application rate can increase crop yield while reducing the environmental risks. However, the optimal N rates vary substantially when different targets such as maximum yield or maximum economic benefit are considered. Taking the wheat-maize rotation cropping system on the North China Plain as a case study, we quantified the variation of N application rates when targeting constraints on yield, economic performance, N uptake and N utilization, by conducting field experiments between 2011 and 2013. Results showed that the optimal N application rate was highest when targeting N uptake (240kgha-1 for maize, and 326kgha-1 for wheat), followed by crop yield (208kgha-1 for maize, and 277kgha-1 for wheat) and economic income (191kgha-1 for maize, and 253kgha-1 for wheat). If environmental costs were considered, the optimal N application rates were further reduced by 20-30% compared to those when targeting maximum economic income. However, the optimal N rate, with environmental cost included, may result in soil nutrient mining under maize, and an extra input of 43kgNha-1 was needed to make the soil N balanced and maintain soil fertility in the long term. To obtain a win-win situation for both yield and environment, the optimal N rate should be controlled at 179kgha-1 for maize, which could achieve above 99.5% of maximum yield and have a favorable N balance, and at 202kgha-1 for wheat to achieve 97.4% of maximum yield, which was about 20kgNha-1 higher than that when N surplus was nil. Although these optimal N rates vary on spatial and temporal scales, they are still effective for the North China Plain where 32% of China's total maize and 45% of China's total wheat are produced. More experiments are still needed to determine the optimal N application rates in other regions. Use of these different optimal N rates would contribute to improving the sustainability of agricultural development in China.

18.
Mol Med Rep ; 15(3): 1393-1400, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28138695

RESUMO

5-Aminolevulinic acid-mediated photodynamic therapy (ALA­PDT) is an effective treatment option for cervical intraepithelial neoplasia, the precancerous lesion of cervical cancer, and early cervical cancer, particularly for young or nulliparous women who want to remain fertile. A previous report described the involvement of histone deacetylases (HDAC) during ALA­PDT mediated apoptosis in the cerebral cortex of a mouse model. Retinoblastoma­associated protein 48 (RbAp48), a highly abundant component of HDACs, is a critical mediator that controls the transforming activity of human papillomavirus 16 in cervical cancer cells. The aim of the present study was to investigate the involvement of RbAp48 in ALA­PDT­induced cell death in cervical cancer cells. RbAp48 was significantly upregulated in cervical cancer cell lines treated with ALA­PDT, including SiHa and HeLa cells. To establish the relevance of RbAp48 and the efficacy of ALA­PDT in cervical cancer cells, the effect of ALA­PDT was investigated in SiHa or HeLa cells following the depletion of RbAp48 by small interfering RNA (siRNA). Reduction of RbAp48 led to the reduced suppression of proliferation and apoptosis induced by ALA­PDT in cervical cancer cells, which was associated with a reduction in tumor suppressor protein 53 (p53), retinoblastoma (Rb), apoptosis­related enzyme caspase­3, and increased levels of the oncogenic genes, human papillomavirus E6 and E7. These results provide evidence that RbAp48 is an important contributor to the efficacy of ALA­PDT in cervical cancer cells. RbAp48 may be a therapeutic target that may help to improve the treatment of cervical cancer.


Assuntos
Luz , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Proteína 4 de Ligação ao Retinoblastoma/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Inativação Gênica , Células HeLa , Humanos , Camundongos , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno , Proteína 4 de Ligação ao Retinoblastoma/metabolismo
19.
Huan Jing Ke Xue ; 38(12): 5047-5055, 2017 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964563

RESUMO

Based on monitoring data of the water quality in the Wuxi port estuary of Taihu Lake from 2010 to 2015, we studied the temporal variation characteristics of nitrogen and its response to rainfall in Wuxi port. The results showed that the pollution level in Wuxi port is serious, with an average annual total nitrogen (TN) concentration of (4.41-5.92 mg·L-1), worse than the water environment quality grade Ⅴ standard (2 mg·L-1). The ammonia nitrogen (NH4+-N) concentration was 1.09-1.72 mg·L-1. The concentrations of TN and NH4+-N showed obvious seasonal variations, with the concentration of TN and NH4+-N in summer and autumn higher than in spring and winter. The concentration of TN in 2015, 2012, and 2011 was 5.92, 5.82, and 5.47 mg·L-1, respectively, which was significantly higher than in 2013 and 2014. The concentration of NH4+-N in 2011 (1.72 mg·L-1) was higher than in 2013 and 2015. With the increase of rainfall intensity, the TN concentration showed an increase after the first downward trend and then a decrease, while the NH4+-N concentration increased first and then decreased. In addition, the nitrogen concentration in the non-flood season was higher than in the flood season.

20.
Huan Jing Ke Xue ; 38(9): 3657-3665, 2017 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965244

RESUMO

The source of pollutants in the Tai Lake basin and the characteristics of spatiotemporal variations were studied by conducting water quality monitoring in the Lihe River watershed to the west of Tai Lake in 2014. The dynamic changes in total phosphorus (TP), ammonia nitrogen (NH4+-N), and chemical oxygen demand (COD) were studied in flood and non-flood seasons at five monitoring points from upstream to downstream. The average concentrations of TP, NH4+-N, and COD were 0.176 mg·L-1, 1.075 mg·L-1, and 10.626 mg·L-1 respectively, and the water quality was lower than the grade Ⅳ standard. From upstream to downstream, the concentrations of TP and NH4+-N gradually increased. The water quality downstream was poor, worse than the gradeⅤstandard; however, COD was low and met the grade Ⅳ standard. During the non-flood season, the pollutant concentrations gradually increased from upstream to downstream. There was no obvious trend in flood season. Concentrations of pollutants gradually increased with the increase in the area of inhabited land and decrease in the area of forest land. The population density, livestock, and poultry production were significantly correlated with the concentrations of pollutants in the river. The pollutants in the Lihe River watershed mainly originated from human activities, and livestock and poultry breeding activities.

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