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1.
Food Chem ; 454: 139796, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38797102

RESUMO

This study aimed to present a selective and effective method for analyzing quinolones (QNs) in food matrix. Herein, a NiFe2O4-based magnetic sodium disulfonate covalent organic framework (NiFe2O4/COF) was prepared using a simple solvent-free grinding method, and was adopted as a selective adsorbent for magnetic solid phase extraction of QNs. Coupled with UHPLC-Q-Orbitrap HRMS, an efficient method for simultaneous detection of 18 kinds of QNs was established. The method exhibited good linearity (0.01-100 ng g-1), high sensitivity (LODs ranging from 0.0011 to 0.0652 ng g-1) and precision (RSDs below 9.5%). Successful extraction of QNs from liver and kidney samples was achieved with satisfactory recoveries ranging from 82.2% to 108.4%. The abundant sulfonate functional groups on NiFe2O4/COF facilitated strong affinity to QNs through electrostatic and hydrogen bonding interactions. The proposed method provides a new idea for the extraction of contaminants with target selectivity.


Assuntos
Compostos Férricos , Contaminação de Alimentos , Estruturas Metalorgânicas , Quinolonas , Extração em Fase Sólida , Extração em Fase Sólida/métodos , Extração em Fase Sólida/instrumentação , Quinolonas/análise , Quinolonas/isolamento & purificação , Quinolonas/química , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/análise , Animais , Estruturas Metalorgânicas/química , Compostos Férricos/química , Níquel/química , Níquel/análise , Níquel/isolamento & purificação , Espectrometria de Massas , Adsorção , Fígado/química
2.
ACS Appl Bio Mater ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38556979

RESUMO

Recent advances have been made in second near-infrared (NIR-II) fluorescence bioimaging and many related applications because of its advantages of deep penetration, high resolution, minimal invasiveness, and good dynamic visualization. To achieve high-performance NIR-II fluorescence bioimaging, various materials and probes with bright NIR-II emission have been extensively explored in the past few years. Among these NIR-II emissive materials, conjugated polymers and conjugated small molecules have attracted wide interest due to their native biosafety and tunable optical performance. This review summarizes the brightness strategies available for NIR-II emissive conjugated materials and highlights the recent developments in NIR-II fluorescence bioimaging. A concise, detailed overview of the molecular design and regulatory approaches is provided in terms of their high brightness, long wavelengths, and superior imaging performance. Then, various typical cases in which bright conjugated materials are used as NIR-II probes are introduced by providing step-by-step examples. Finally, the current problems and challenges associated with accessing NIR-II emissive conjugated materials for bright NIR-II fluorescence bioimaging are briefly discussed, and the significance and future prospects of these materials are proposed to offer helpful guidance for the development of NIR-II emissive materials.

3.
Nanoscale ; 16(7): 3422-3429, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38284457

RESUMO

Bacterial biosynthesis of nanomaterials has several advantages (e.g., reduced energy inputs, lower cost, negligible environmental pollution) compared with traditional approaches. Various nanomaterials have been produced by bacteria. However, reports on using the bacterial biosynthesis of nanomaterials for applications with solar-thermal agents are scarce due to their narrow optical absorption. Herein, for the first time, we proposed a bacterial biosynthesis of broad-absorbing tellurium nanoneedles and demonstrated their effectiveness for solar-thermal evaporation and antibacterial applications. By simple biosynthesis within bacteria (Shewanella oneidensis MR-1), tellurium nanoneedles achieved a superfine configuration with a length-to-diameter ratio of nearly 20 and broad-spectrum absorbance. After integrating tellurium nanoneedles into a porous polyvinyl-alcohol scaffold, a solar-thermal still named TSAS-3 realized a high evaporation rate of 2.25 kg m-2 h-1 and solar-thermal conversion efficiency of 81% upon 1-Sun illumination. Based on these unique properties, the scaffold displayed good performances in seawater desalination, multiple wastewater treatment, and antibacterial applications. This work provides a simple and feasible strategy for the use of microbial-synthesized nanomaterials in solar-driven water purification and antibacterial applications.


Assuntos
Nanoestruturas , Purificação da Água , Telúrio , Antibacterianos/farmacologia , Álcool de Polivinil , Água
4.
Nanomicro Lett ; 16(1): 21, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37982963

RESUMO

Massive efforts have been concentrated on the advance of eminent near-infrared (NIR) photothermal materials (PTMs) in the NIR-II window (1000-1700 nm), especially organic PTMs because of their intrinsic biological safety compared with inorganic PTMs. However, so far, only a few NIR-II-responsive organic PTMs was explored, and their photothermal conversion efficiencies (PCEs) still remain relatively low. Herein, donor-acceptor conjugated diradical polymers with open-shell characteristics are explored for synergistically photothermal immunotherapy of metastatic tumors in the NIR-II window. By employing side-chain regulation, the conjugated diradical polymer TTB-2 with obvious NIR-II absorption was developed, and its nanoparticles realize a record-breaking PCE of 87.7% upon NIR-II light illustration. In vitro and in vivo experiments demonstrate that TTB-2 nanoparticles show good tumor photoablation with navigation of photoacoustic imaging in the NIR-II window, without any side-effect. Moreover, by combining with PD-1 antibody, the pulmonary metastasis of breast cancer is high-effectively prevented by the efficient photo-immunity effect. Thus, this study explores superior PTMs for cancer metastasis theranostics in the NIR-II window, offering a new horizon in developing radical-characteristic NIR-II photothermal materials.

5.
JMIR Public Health Surveill ; 9: e44647, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37252771

RESUMO

BACKGROUND: Multimorbidity is characterized by the co-occurrence of 2 or more chronic diseases and has been a focus of the health care sector and health policy makers due to its severe adverse effects. OBJECTIVE: This paper aims to use the latest 2 decades of national health data in Brazil to analyze the effects of demographic factors and predict the impact of various risk factors on multimorbidity. METHODS: Data analysis methods include descriptive analysis, logistic regression, and nomogram prediction. The study makes use of a set of national cross-sectional data with a sample size of 877,032. The study used data from 1998, 2003, and 2008 from the Brazilian National Household Sample Survey, and from 2013 and 2019 from the Brazilian National Health Survey. We developed a logistic regression model to assess the influence of risk factors on multimorbidity and predict the influence of the key risk factors in the future, based on the prevalence of multimorbidity in Brazil. RESULTS: Overall, females were 1.7 times more likely to experience multimorbidity than males (odds ratio [OR] 1.72, 95% CI 1.69-1.74). The prevalence of multimorbidity among unemployed individuals was 1.5 times that of employed individuals (OR 1.51, 95% CI 1.49-1.53). Multimorbidity prevalence increased significantly with age. People over 60 years of age were about 20 times more likely to have multiple chronic diseases than those between 18 and 29 years of age (OR 19.6, 95% CI 19.15-20.07). The prevalence of multimorbidity in illiterate individuals was 1.2 times that in literate ones (OR 1.26, 95% CI 1.24-1.28). The subjective well-being of seniors without multimorbidity was 15 times that among people with multimorbidity (OR 15.29, 95% CI 14.97-15.63). Adults with multimorbidity were more than 1.5 times more likely to be hospitalized than those without (OR 1.53, 95% CI 1.50-1.56) and 1.9 times more likely need medical care (OR 1.94, 95% CI 1.91-1.97). These patterns were similar in all 5 cohort studies and remained stable for over 21 years. A nomogram model was used to predict multimorbidity prevalence under the influence of various risk factors. The prediction results were consistent with the effects of logistic regression; older age and poorer participant well-being had the strongest correlation with multimorbidity. CONCLUSIONS: Our study shows that multimorbidity prevalence varied little in the past 2 decades but varies widely across social groups. Identifying populations with higher rates of multimorbidity prevalence may improve policy making around multimorbidity prevention and management. The Brazilian government can create public health policies targeting these groups, and provide more medical treatment and health services to support and protect the multimorbidity population.


Assuntos
Multimorbidade , Adulto , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Comorbidade , Brasil/epidemiologia , Estudos Transversais , Doença Crônica
6.
J Environ Manage ; 321: 115919, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36001914

RESUMO

Plant and soil microbial community composition play a central role in maintaining ecosystem functioning. Most studies have focused on soil microbes in the bulk soil, the rhizosphere and inside plant roots, however, less is known about the soil community that exists within soil aggregates, and how these soil communities influence plant biomass production. Here, using field-conditioned soil collected from experimental ungrazed and grazed grasslands in Inner Mongolia, China, we examined the composition of microbiomes inside soil aggregates of various size classes, and determined their roles in plant-soil feedbacks (PSFs), diversity-productivity relationships, and diversity-dependent overyielding. We found that grazing induced significantly positive PSF effects, which appeared to be mediated by mycorrhizal fungi, particularly under plant monocultures. Despite this, non-additive effects of microbiomes within different soil aggregates enhanced the strength of PSF under ungrazed grassland, but decreased PSF strength under intensively grazed grassland. Plant mixture-related increases in PSF effects markedly enhanced diversity-dependent overyielding, primarily due to complementary effects. Selection effects played far less of a role. Our work suggests that PSF contributes to diversity-dependent overyielding in grasslands via non-additive effects of microbiomes within different soil aggregates. The implication of our work is that assessing the effectiveness of sustainable grassland restoration and management on soil properties requires inspection of soil aggregate size-specific microbiomes, as these are relevant determinants of the feedback interactions between soil and plant performance.


Assuntos
Microbiota , Solo , Biomassa , Ecossistema , Pradaria , Plantas , Microbiologia do Solo
7.
Front Plant Sci ; 12: 684503, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34421941

RESUMO

Shoot defoliation by grazers or mowing can affect root traits of grassland species, which may subsequently affect its aboveground traits and ecosystem functioning (e.g., aboveground primary production). However, experimental evidence for such reciprocal feedback between shoots and roots is limited. We grew the perennial grass Leymus chinensis-common across the eastern Eurasian steppe-as model species in a controlled-hydroponics experiment, and then removed half of its shoots, half of its roots, or a combination of both. We measured a range of plant aboveground and belowground traits (e.g., phenotypic characteristics, photosynthetic traits, root architecture) in response to the shoot and/or root removal treatments. We found the regenerated biomass was less than the lost biomass under both shoot defoliation and root severance, generating a under-compensatory growth. Root biomass was reduced by 60.11% in the defoliation treatment, while root severance indirectly reduced shoot biomass by 40.49%, indicating a feedback loop between shoot and root growth. This defoliation-induced shoot-root feedback was mediated by the disproportionate response and allometry of plant traits. Further, the effect of shoot defoliation and root severance on trait plasticity of L. chinensis was sub-additive. That is, the combined effects of the two treatments were less than the sum of their independent effects, resulting in a buffering effect on the existing negative influences on plant persistence by increased photosynthesis. Our results highlight the key role of trait plasticity in driving shoot-root reciprocal feedbacks and growth persistence in grassland plants, especially perennial species. This knowledge adds to earlier findings of legacy effects and can be used to determine the resilience of grasslands.

8.
Front Plant Sci ; 12: 640789, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34381466

RESUMO

Grazing exclusion is an effective management practice to restore grassland ecosystem functioning. However, little is known about the role of soil microbial communities in regulating grassland ecosystem functioning during long-term ecosystem restorations. We evaluated the recovery of a degraded semiarid grassland ecosystem in northern China by investigating plant and soil characteristics and the role of soil microbial communities in ecosystem functioning after 22 years of grazing exclusion. Grazing exclusion significantly increased the alpha diversity and changed the community structure of bacteria, but did not significantly affect the alpha diversity or community structure of fungi. The higher abundance of copiotrophic Proteobacteria and Bacteroidetes with grazing exclusion was due to the higher carbon and nutrient concentrations in the soil, whereas the high abundance of Acidobacteria in overgrazed soils was likely an adaptation to the poor environmental conditions. Bacteria of the Sphingomonadaceae family were associated with C cycling under grazing exclusion. Bacteria of the Nitrospiraceae family, and especially of the Nitrospira genus, played an important role in changes to the N cycle under long-term exclusion of grazing. Quantitative PCR further revealed that grazing exclusion significantly increased the abundance of nitrogen fixing bacteria (nifH), ammonia oxidizers (AOA and AOB), and denitrifying bacteria (nirK and nosZ1). Denitrifying enzyme activity (DEA) was positively correlated with abundance of denitrifying bacteria. The increase in DEA under grazing exclusion suggests that the dependence of DEA on the availability of NO3 - produced is due to the combined activity of ammonia oxidizers and denitrifiers. Our findings indicate that decades-long grazing exclusion can trigger changes in the soil bacterial diversity and composition, thus modulating the restoration of grassland ecosystem functions, carbon sequestration and soil fertility.

9.
PeerJ ; 8: e9915, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32999765

RESUMO

Nutrient resorption from senesced leaves is an important mechanism for nutrient conservation in plants. However, little is known about the effect of grazing on plant nutrient resorption from senesced leaves, especially in semiarid ecosystems. Here, we evaluated the effects of grazing on N and P resorption in the three most dominant grass species in a typical steppe in northern China. We identified the key pathways of grazing-induced effects on N and P resorption efficiency. Grazing increased N and P concentrations in the green leaves of Leymus chinensis and Stipa grandis but not in Cleistogenes squarossa. Both L. chinensis and S. grandis exhibited an increasing trend of leaf N resorption, whereas C. squarrosa recorded a decline in both leaf N and P resorption efficiency under grazing. Structural equation models showed that grazing is the primary driver of the changes in N resorption efficiency of the three dominant grass species. For L. chinensis, the P concentration in green and senesced leaves increased the P resorption efficiency, whereas the senesced leaf P concentration played an important role in the P resorption efficiency of C. squarrosa. Grazing directly drove the change in P resorption efficiency of S. grandis. Our results suggest that large variations in nutrient resorption patterns among plant species depend on leaf nutritional status and nutrient-use strategies under overgrazing, and indicate that overgrazing may have indirect effects on plant-mediated nutrient cycling via inducing shifts in the dominance of the three plant species.

10.
PeerJ ; 8: e10116, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33083144

RESUMO

There is growing evidence that herbivory-induced legacy effects permit plants to cope with herbivory. However, herbivory-induced defense strategies in plants against grazing mammals have received little attention. To further understand the grazing-induced legacy effects on plants, we conducted a greenhouse experiment with Leymus chinensis experiencing different grazing histories. We focused on grazing-induced legacy effects on above-ground spatial avoidance and below-ground biomass allocation. Our results showed that L. chinensis collected from the continuous overgrazing plot (OG) exhibited higher performance under simulated grazing in terms of growth, cloning and colonizing ability than those collected from the 35-year no-grazing plot (NG). The enhanced adaptability of OG was attributed to increased above-ground spatial avoidance, which was mediated by larger leaf angle and shorter height (reduced vertical height and increased leaf angle contributed to the above-ground spatial avoidance at a lower herbivory stubble height, while reduced tiller natural height contributed to above-ground spatial avoidance at a higher herbivory stubble height). Contrary to our prediction, OG pre-allocated less biomass to the rhizome, which does not benefit the herbivory tolerance and avoidance of L. chinensis; however, this also may reflect a tolerance strategy where reduced allocation to rhizomes is associated with increased production of ramets.

11.
PeerJ ; 8: e9266, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32596041

RESUMO

Grazing, one of the primary utilization modes of grassland, is the main cause of grassland degradation. Historical overgrazing results in dwarf phenotype and decreased photosynthesis of perennial plants. However, it remains unknown what the mechanism underlying of this legacy effect is, and the role of stomata in the resulting decreased photosynthesis also remains unclear. To address these questions, differences in stomatal density, length and width on both adaxial and abaxial epidermis were compared between overgrazing and ungrazed Leymus chinensis offspring by using rhizome buds cultivated in a greenhouse, and the correlation between photosynthetic capacity and stomatal behavior was also investigated. Our results showed that historical grazing significantly impacted phenotype, photosynthesis and stomatal traits of L. chinensis. The offspring plants taken from overgrazed parents were dwarfed compared to those taken from ungrazed parents, and the photosynthesis and stomatal conductance of plants with a grazing history decreased by 28.6% and 21.3%, respectively. In addition, stomatal density and length on adaxial and abaxial leaf surfaces were significantly increased; however, stomatal width on abaxial leaf surfaces of overgrazed L. chinensis was significantly decreased compared with ungrazed individuals. Moreover, the expression patterns of eight genes related to stomatal regulation were tested: seven were down-regulated (2-18 times) and one was up-regulated (three times). Genes, involved in ABC transporter and receptor-like serine/threonine protein kinase were down-regulated. These results suggest that legacy effects of historical grazing affect the stomatal conductance by decreasing the stomatal width in progeny plants, which thus results in lower photosynthesis. Furthermore, changes of stomatal traits and function were regulated by the inhibition of ABC transporter and serine/threonine protein kinase. These findings are helpful for future exploration of the possible mechanisms underlying the response of grassland plants to long-term overgrazing.

12.
Chem Commun (Camb) ; 55(63): 9279-9282, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31287458

RESUMO

Ni2P@C facilely prepared by microwave assisted combustion with phytic acid and nickel nitrate followed by reduction at 650 °C exhibits even higher activity for the hydrodechlorination of HCFC-22 than Pd/C. This method is also applicable for the synthesis of other metal phosphides, providing a versatile method for the fabrication of carbon encapsulated metal phosphide particles.

13.
PeerJ ; 7: e7047, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31218124

RESUMO

BACKGROUND: Vegetation succession is one of the major driving processes of grassland degradation. Stoichiometry significantly contributes to vegetation dynamics. However, a knowledge gap exists in how soil nutrients and root enzymes influence the stoichiometric ratio to affect vegetation dynamics. METHODS: To address these questions, we selected a dominant species (Leymus chinensis (Trin.) Tzvel.) and a degraded-dominant species (Artemisia frigida Willd.) under different management regimes (enclosure and grazing) on the Inner Mongolia steppe. We measured (i) plant nutrient concentrations, (ii) root enzymes and (iii) soil nutrients to investigate how the selected plant species responded to grazing. RESULTS: The results show that: (i) N and P concentrations and the C:N:P ratio in different organs are significantly affected by grazing, and there is variation in the plant species' response. Grazing significantly increased N and P in the leaves and stems of L. chinensis and the stems and roots of A. frigida. (ii) Grazing significantly increased the activities of glutamine synthase but decreased the activities of acid phosphatase in L. chinensis. The nitrate reductase and acid phosphatase activities significantly increased in A. frigida under grazing conditions. (iii) Grazing decreased the total nitrogen, total phosphorus, and available nitrogen, but increased the available phosphorus in the soil. CONCLUSION: We conclude that A. frigida is better adapted to grazing than L. chinensis, possibly because of its relatively increased stem and root growth, which enhance population expansion following grazing. Conversely, L. chinensis showed increased leaf and stem growth, but suffered nutrient and biomass loss as a result of excessive foraging by livestock, which severely affected its ability to colonize. Root enzymes coupled with soil nutrients can regulate plant nutrients and stoichiometric ratios as an adaptive response to grazing. Thus, we demonstrated that stoichiometric ratios allow species to better withstand grazing disturbances. This study provides a new understanding of the mechanisms involved in grazing-resistance within a plant-soil system.

14.
BMC Plant Biol ; 19(1): 205, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31109303

RESUMO

BACKGROUND: Fall dormancy and freezing tolerance characterized as two important phenotypic traits, have great effects on productivity and persistence of alfalfa (Medicago sativa L.). Despite the fact that one of the most limiting traits for alfalfa freezing tolerance in winter is fall dormancy, the interplay between fall dormancy and cold acclimation processes of alfalfa remains largely unknown. We compared the plant regrowth, winter survival, raffinose and amino acids accumulation, and genome-wide differentially expressed genes of fall-dormant cultivar with non-dormant cultivar under cold acclimation. RESULTS: Averaged over both years, the non-dormant alfalfa exhibited largely rapid regrowth compared with fall dormant alfalfa after last cutting in autumn, but the winter survival rate of fall dormant alfalfa was about 34-fold higher than that of non-dormant alfalfa. The accumulation of raffinose and amino acids were significantly increased in fall dormant alfalfa, whereas were decreased in non-dormant alfalfa under cold acclimation. Expressions of candidate genes encoding raffinose biosynthesis genes were highly up-regulated in fall dormant alfalfa, but down-regulated in non-dormant alfalfa under cold acclimation. In fall dormant alfalfa, there was a significantly down-regulated expression of candidate genes encoding the glutamine synthase, which is indirectly involved in the proline metabolism. A total of eight significantly differentially expressed transcription factors (TFs) related to CBF and ABRE-BFs were identified. The most up-regulated TFs in fall dormant alfalfa cultivar were ABF4 and DREB1C. CONCLUSIONS: Fall dormant alfalfa drastically increased raffinose and amino acids accumulation under cold acclimation. Raffinose-associated and amino acid-associated genes involved in metabolic pathways were more highly expressed in fall dormant alfalfa than non-dormant alfalfa under cold acclimation. This global survey of transcriptome profiles provides new insights into the interplay between fall dormancy and cold acclimation in alfalfa.


Assuntos
Regulação da Expressão Gênica de Plantas/fisiologia , Medicago sativa/fisiologia , Dormência de Plantas/genética , Proteínas de Plantas/genética , Transcriptoma/fisiologia , Perfilação da Expressão Gênica , Longevidade , Medicago sativa/genética , Estações do Ano
15.
Molecules ; 24(2)2019 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-30669524

RESUMO

Cr2O3 nanoparticles were prepared by solution combustion synthesis (SCS) with chromium nitrate as the precursor and glycine as the fuel. Commercial Cr2O3 and Cr2O3 prepared by a precipitation method were also included for comparison. The morphology, structure, acidity and particle size of fresh and spent Cr2O3 catalysts were investigated by techniques such as XRD, SEM, TEM, BET and NH3-TPD. In addition, catalytic performance was evaluated for the dehydrofluorination of 1,1,1,3,3-pentafluoropropane (CF3CH2CHF2, HFC-245fa) to 1,3,3,3-tetra-fluoropropene (CF3CH=CHF, HFO-1234ze). The catalytic reaction rate of Cr2O3 prepared by SCS method is as high as 6 mmol/h/g, which is about 1.5 times and 2 times higher than that of precipitated Cr2O3 and commercial Cr2O3, respectively. The selectivity to HFO-1234ze for all the catalysts maintains at about 80%. Compared with commercial and precipitated Cr2O3, Cr2O3-SCS prepared by SCS possesses higher specific surface area and acid amount. Furthermore, significant change in the crystal size of Cr2O3 prepared by SCS after reaction was not detected, indicating high resistance to sintering.


Assuntos
Compostos de Cromo/síntese química , Fluorocarbonos/química , Hidrocarbonetos Fluorados/química , Nanopartículas/química , Catálise , Halogenação , Concentração de Íons de Hidrogênio , Oxirredução , Tamanho da Partícula , Soluções , Propriedades de Superfície
16.
Ecotoxicol Environ Saf ; 170: 166-171, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30529615

RESUMO

PM2.5 particles were collected to study the distribution, accumulation and health risk assessment of metal pollutants. The concentrations of 11 kinds of metal elements in PM2.5 during heating period and non-heating period were analyzed. Based on the American health risk assessment model as well as the human exposure parameters in China, the human health risk was assessed. The concentrations of metal components in PM2.5 during the heating period were, in descending order, Pb, Mn, Cr, As, Sb, Se, Ni, Cd, Tl, Hg, and Be, while during the non-heating period, they were basically in the same order, except Cd and Ni, as the concentration of the former was a little higher than that of the latter. The concentrations of As, Cd, Hg, Ni, Se, and Tl were quite different in the heating period and non-heating period. The non-carcinogenic risks caused by metal elements were lower than the minimum acceptance 10-6 per year during both the heating period and non-heating period. The non-carcinogenic results of a descending order were Pb, Mn, Sb, Tl, Se, and Hg. The carcinogenic risks of a descending order were Cr, As, Cd, Ni, and Be. The risks of As and Cr to children were over 10-6. Hence, As and Cr should be considered as priorities.


Assuntos
Poluentes Ambientais/análise , Poluição Ambiental , Metais Pesados/análise , Material Particulado/análise , Adulto , Calibragem , Carcinógenos/toxicidade , Criança , China , Feminino , Humanos , Masculino , Modelos Teóricos , Medição de Risco , Estações do Ano
17.
Mol Biol Rep ; 45(6): 2609-2614, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30357585

RESUMO

The germination and growth of seedlings are not only essential stages in plant growth but also indicator of environmental stress. Evaluation of seed germination and early seedling in order to improve the understanding of influential processes of exogenic substances. This study aimed to reveal the possible toxicity of antimony (Sb) using Raphanus sativus L. Radish (radish) and Brassica napus L. (rape) seeds as the experimental materials. With Sb concentrations ranging from 2 to 100 mg/L, the seed germination and seedlings growth were investigated by calculating the germination rate, germinative energy, germination index, vitality index and root elongation. The results indicated that Sb exhibited different levels of toxicity to different plants. The low concentration of Sb increased the germination rate and germination index of rape seeds, whereas high concentrations of Sb sharply decreased the germination rate and germination index when the Sb was greater than 10 mg/L. The radish seeds remained almost constant. The germinative energy of both seeds exhibited the same change. In addition, the root elongation was more sensitive to the antimony pollution than the germination rate was. The vitality index decayed exponentially as the Sb concentration increased for both species of seed. These results have significant ecological meaning in assessing the toxicity of Sb.


Assuntos
Antimônio/toxicidade , Brassica napus/efeitos dos fármacos , Raphanus/efeitos dos fármacos , Germinação/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Plântula/efeitos dos fármacos , Sementes/efeitos dos fármacos
18.
Zhongguo Zhen Jiu ; 38(8): 853-6, 2018 Aug 12.
Artigo em Chinês | MEDLINE | ID: mdl-30141296

RESUMO

To summarize professor SUN Xuequan's own experience on the acupuncture sensation. Professor SUN Xuequan puts forward his opinion through the sensation of acupuncture on himself, from the aspects of the expression, the material basis, the distinction and the clinical significance of acupuncture sensation, etc. Professor SUN thinks that the production and conduction direction of acupuncture sensation have their material basis and objectively exist, based on which, professor SUN puts forward the amount of acupuncture stimulation and the total amount of acupuncture stimulation. Professor SUN believes that the amount of acupuncture stimulation is the main basis for the individual reinforcing and reducing of acupuncture. The amount of acupuncture stimulation is related to the depth and intensity of acupuncture, the time of the needle retention, the number of needles, etc. The reinforcing and reducing of acupuncture are relative to the deficiency and excess of the disease, and they are the reaction of acupuncture for body. The tolerance degree of the individual to the stimulation of acupuncture is also the main factor affecting the reinforcing and reducing.


Assuntos
Terapia por Acupuntura , Agulhas , Sensação
19.
BMC Plant Biol ; 18(1): 81, 2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-29739327

RESUMO

BACKGROUND: This study was designed to reveal potential molecular mechanisms of long-term overgrazing-induced dwarfism in sheepgrass (Leymus chinensis). METHODS: An electrospray ionisation mass spectrometry system was used to generate proteomic data of dwarf sheepgrass from a long-term overgrazed rangeland and normal sheepgrass from a long-term enclosed rangeland. Differentially expressed proteins (DEPs) between dwarf and normal sheepgrass were identified, after which their potential functions and interactions with each other were predicted. The expression of key DEPs was confirmed by high-performance liquid chromatography mass spectrometry (HPLC-MS) using a multiple reaction monitoring method. RESULTS: Compared with normal sheepgrass, a total of 51 upregulated and 53 downregulated proteins were identified in dwarf sheepgrass. The amino acids biosynthesis pathway was differentially enriched between the two conditions presenting DEPs, such as SAT5_ARATH and DAPA_MAIZE. The protein-protein interaction (PPI) network revealed a possible interaction between RPOB2_LEPTE, A0A023H9M8_9STRA, ATPB_DIOEL, RBL_AMOTI and DNAK_GRATL. Four modules were also extracted from the PPI network. The HPLC-MS analysis confirmed the upregulation and downregulation of ATPB_DIOEL and DNAK_GRATL, respectively in dwarf samples compared with in the controls. CONCLUSIONS: The upregulated ATPB_DIOEL and downregulated DNAK_GRATL as well as proteins that interact with them, such as RPOB2_LEPTE, A0A023H9M8_9STRA and RBL_AMOTI, may be associated with the long-term overgrazing-induced dwarfism in sheepgrass.


Assuntos
Proteínas de Plantas/metabolismo , Poaceae/crescimento & desenvolvimento , Aminoácidos/metabolismo , Criação de Animais Domésticos , Cromatografia Líquida de Alta Pressão , Regulação da Expressão Gênica de Plantas , Espectrometria de Massas , Redes e Vias Metabólicas , Proteínas de Plantas/fisiologia , Poaceae/metabolismo , Poaceae/fisiologia , Proteômica , Espectrometria de Massas por Ionização por Electrospray
20.
Microscopy (Oxf) ; 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29750255

RESUMO

Nucleolus structure alters as the cell cycle is progressing. It is established in telophase, maintained throughout the entire interphase and disassembled in metaphase. Fibrillar centers (FCs), dense fibrillar components (DFCs) and granular components (GCs) are essential nucleolar organizations where rRNA transcription and processing and ribosome assembly take place. Hitherto, little is known about the cell cycle-dependent reorganization of these structures. In this study, we followed the nucleolus structure during the cell cycle by electron microscopy (EM). We found the nucleolus experienced multiple rounds of structural reorganization within a single cell cycle: (1) when nucleoli are formed during the transition from late M to G1 phase, FCs, DFCs and GCs are constructed, leading to the establishment of tripartite nucleolus; (2) as FC/DFCs are disrupted at mid-G1, tripartite nucleolus is gradually changed into a bipartite organization; (3) at late G1, the reassembly of FC/DFCs results in a structural transition from bipartite nucleolus towards tripartite nucleolus; (4) as cells enter S phase, FC/DFCs are disassembled again and tripartite nucleolus is thus changed into a bipartite organization. Of note, FC/DFCs were not observed until late S phase; (5) FC/DFCs experience structural disruption and restoration during G2 and (6) when cells are at mitotic stage, FC/DFCs disappear before nucleolus structure is disassembled. These results also suggest that bipartite nucleolus can exist in higher eukaryotes at certain period of the cell cycle. As structures are the fundamental basis of diverse cell activities, unveiling the structural reorganization of nucleolar FCs and DFCs may bring insights into the spatial-temporal compartmentalization of relevant cellular functions.

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