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1.
Sci Total Environ ; 716: 137145, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32069696

RESUMO

This study evaluated a newly developed sensing device, AS-LUNG-O, against a research-grade GRIMM in laboratory and ambient conditions and used AS-LUNG-O to assess PM2.5 spatiotemporal variations at street levels of an Asian mountain community, which represented residents' exposure (at the interface of atmosphere and human bodies leading to potential health impacts). In laboratory, R2 of 1-min AS-LUNG-O and GRIMM was 0.95 ± 0.04 (n = 64,179 for 40 sets). After conversion with individual correction equations, their correlation in ambient tests was 0.93 ± 0.05, with absolute % difference of only 10 ± 9%. Ten AS-LUNG-O sets were installed at street sites with another one at 10 m above ground on July 1-28 and December 2-31, 2017 in Nantou, Taiwan. Important source contributions to PM2.5 were quantified with regression analysis. Temporal variation expressed as the daily max/mean of 5-min PM2.5 reached 13.7 in July and 12.2 in December. Spatial variation expressed as the percent coefficients of variance (%CV) across ten community locations was 22% ± 20% (max: 199%) in July and 19 ± 18% (max: 206%) in December. Incremental contribution from the stop-and-go traffic, market, temple, and fried-chicken vendor to PM2.5 at 3-5 m away were 4.38, 3.90, 2.72, and 1.80 µg/m3, respectively. Significant spatiotemporal variations and community source contributions revealed the importance of assessing neighborhood air quality for public health protection. For long-term air quality monitoring, the percentage of available power and signals of G-sensor provided indicative information of maintenance required. Advantages of low cost (USD 650), small size, light weight, solar power supply, backup data storage, waterproof housing, multiple-sensor flexibility, and high precision and accuracy (after correction) enable AS-LUNG-O to be widely applied in environmental studies.

2.
Development ; 147(1)2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31806662

RESUMO

Although cytokinesis has been intensely studied, the way it is executed during development is not well understood, despite a long-standing appreciation that various aspects of cytokinesis vary across cell and tissue types. To address this, we investigated cytokinesis during the invariant Caenorhabditis elegans embryonic divisions and found several parameters that are altered at different stages in a reproducible manner. During early divisions, furrow ingression asymmetry and midbody inheritance is consistent, suggesting specific regulation of these events. During morphogenesis, we found several unexpected alterations to cytokinesis, including apical midbody migration in polarizing epithelial cells of the gut, pharynx and sensory neurons. Aurora B kinase, which is essential for several aspects of cytokinesis, remains apically localized in each of these tissues after internalization of midbody ring components. Aurora B inactivation disrupts cytokinesis and causes defects in apical structures, even if inactivated post-mitotically. Therefore, we demonstrate that cytokinesis is implemented in a specialized way during epithelial polarization and that Aurora B has a role in the formation of the apical surface.

3.
Int J Mol Sci ; 21(1)2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861919

RESUMO

Akkermansia muciniphila can produce various mucin-degrading proteins. However, the functional characteristics of these proteins and their role in mucin degradation are unclear. Of the predicted protein-coding genes, Amuc_1434, which encodes for a hypothetical protein, is the focus in this study. A recombinant enzyme Amuc_1434 containing the 6× His-tag produced in Escherichia coli (hereinafter termed Amuc_1434*) was isolated to homogeneity and biochemically characterised. Results showed that the enzyme can hydrolyse hemoglobin with an activity of 17.21 U/µg. The optimal pH and temperature for hemoglobin hydrolysis of Amuc_1434* were found to be around 8.0 and 40 °C, respectively. Amuc_1434* is identified as a member of the aspartic protease family through the action of inhibitor pepstatin A. Amuc_1434* promotes the adhesion of colon cancer cell line LS174T, which can highly express Muc2. Significantly Amuc_1434* can degrade Muc2 of colon cancer cells. Amuc_1434 is mainly located in the colon of BALB/c mice. These results suggest that the presence of Amuc_1434 from Akkermansia muciniphila may be correlated with the restoration of gut barrier function by decreasing mucus layer thickness.


Assuntos
Ácido Aspártico Proteases/metabolismo , Proteínas de Bactérias/metabolismo , Mucina-2/metabolismo , Verrucomicrobia/metabolismo , Animais , Ácido Aspártico Proteases/isolamento & purificação , Linhagem Celular Tumoral , Células HeLa , Humanos , Camundongos Endogâmicos BALB C , Proteólise
4.
Mikrochim Acta ; 186(12): 827, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31754798

RESUMO

A core-shell structured magnetic covalent organic frameworks of the type Fe3O4@COFs was prepared by using the Fe3O4 nanoparticles as magnetic core, and 4,4"-diamino-p-terphenyl and 1,3,5-tris(p-formylphenyl)benzene as two building blocks. The Fe3O4@COFs were characterized by scanning electron microscopy, transmission electron microscopy, energy dispersive spectrum, Fourier transform infrared spectroscopy, zeta potentiometric analysis, X-ray diffraction, vibrating sample magnetometry, thermogravimetric analysis and the nitrogen adsorption-desorption isotherms. The Fe3O4@COFs have core-shell structure with average diameter of 200 ± 2.4 nm, a high specific surface area (124 m2·g-1), uniform pore size distribution (3.1 nm), good magnetic responsivity (36.8 emu·g-1), good thermal and chemical stability. They were applied as the sorbents for magnetic solid phase extraction (MSPE) for fluoroquinolones (FQs) ciprofloxacin, enrofloxacin, lomefloxacin, gatifloxacin, levofloxacin and pefloxacin. The effects of sorbent dosage, extraction time, p H value, ionic strength, desorption solvent and desorption time were investigated. By combining MSPE with HPLC-DAD analysis, a rapid and sensitive method was developed for the enrichment and determination of these FQs. The method had good linearity in the range of 2.5-1500 ng·g-1 FQ concentration range and low limits of detection (0.25-0.5 ng·g-1). The method was successfully applied to the extraction and determination of FQs in (spiked) pork, milk and human plasma samples. Recoveries ranged from 78.7-103.5% (with RSD<6.2%). Graphical abstract Schematic representation of the magnetic covalent organic frameworks which prepared by using the Fe3O4 nanoparticles as magnetic core, 4,4"-diamino-p-terphenyl and 1,3,5-tris(p-formylphenyl)benzene as two building blocks. The Fe3O4@COFs were applied as adsorbents for magnetic solid phase extraction of six fluoroquinolones (FQs) and HPLC-DAD was applied to analysis the extraction efficiencies.

5.
Nat Commun ; 10(1): 4762, 2019 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628310

RESUMO

Optical super-resolution microscopy allows nanoscale imaging of protein molecules in intact biological tissues. However, it is still challenging to perform large volume super-resolution imaging for entire animal organs. Here we develop a single-wavelength Bessel lightsheet method, optimized for refractive-index matching with clarified specimens to overcome the aberrations encountered in imaging thick tissues. Using spontaneous blinking fluorophores to label proteins of interest, we resolve the morphology of most, if not all, dopaminergic neurons in the whole adult brain (3.64 × 107 µm3) of Drosophila melanogaster at the nanometer scale with high imaging speed (436 µm3 per second) for localization. Quantitative single-molecule localization reveals the subcellular distribution of a monoamine transporter protein in the axons of a single, identified serotonergic Dorsal Paired Medial (DPM) neuron. Large datasets are obtained from imaging one brain per day to provide a robust statistical analysis of these imaging data.


Assuntos
Encéfalo/diagnóstico por imagem , Drosophila melanogaster/metabolismo , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Animais , Animais Geneticamente Modificados , Encéfalo/metabolismo , Drosophila melanogaster/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Microscopia Confocal/instrumentação , Microscopia de Fluorescência/instrumentação , Reprodutibilidade dos Testes
6.
Ecotoxicol Environ Saf ; 184: 109579, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31505405

RESUMO

DNA methylation have been suggested as possible mediators of long-term health effects of environmental stressors. This study aimed to evaluate the potential therapy of methylation of S-adenosyl-l-methionine (SAM) on PFOS induced trangeneral reproductive toxicity. In this study, postnatal 5d Sprague Dawley rats were randomly divided into four groups: control, PFOS, PFOS + SAM, and PFOS + Decitabine (DAC). The F0 rats were exposed to 5 mg/kg PFOS and SAM or DAC until PND60. The development of the offsprings were monitored without PFOS exposure. The fertility in F0, F1 rats, and change in F1 testes were observed. The results were as follows. The significant increase in F0 pregnancy rate, and survival rate in F1 offspring in PFOS + SAM relative to PFOS group were observed. Changes of birth weights and physical development in F1 offspring with SAM were approached as a corresponding variation of the control after the deparation period. No pregnant in F1 maternal rats in the PFOS and DAC groups were found, but pregnant in the SAM group. Significantly decrease in the percentage of abnormal seminiferous tubules and increase in expression of promyelocytic leukemia zinc finger (PLZF+) spermatogonial stem cells in F1 testis compared with the PFOS group. Taken together, Methyl donor SAM improve PLZF + spermatogonia stem cell proliferation, attenuate damage in testicular tissue structure, which subsequently improve the transgenerational growth retard and infertility induced by PFOS chronic stress.


Assuntos
Ácidos Alcanossulfônicos/toxicidade , Fluorcarbonetos/toxicidade , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Reprodução/efeitos dos fármacos , S-Adenosilmetionina/uso terapêutico , Animais , Peso ao Nascer , Decitabina/uso terapêutico , Feminino , Masculino , Gravidez , Taxa de Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/mortalidade , Efeitos Tardios da Exposição Pré-Natal/patologia , Ratos Sprague-Dawley , Espermatogônias/citologia , Espermatogônias/efeitos dos fármacos , Taxa de Sobrevida , Testículo/citologia , Testículo/efeitos dos fármacos
7.
Psychopharmacology (Berl) ; 236(11): 3301-3315, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31197433

RESUMO

RATIONALE: The volatile anesthetic isoflurane is suggested to produce a rapid and robust antidepressive effect in preliminary clinical trials. Recently, isoflurane was found to activate the tropomyosin receptor kinase B (TrkB) signaling which is the underlying mechanism of the rapid antidepressant ketamine. OBJECTIVE: Our study investigated the effect of isoflurane anesthesia on chronic unpredictable mild stressed (CUMS) model in mice and verified the role of brain-derived neurotrophic factor (BDNF)/TrkB/ the mammalian target of rapamycin (mTOR) signaling in the antidepressant effect of isoflurane. METHODS: We employed the CUMS model of depression to assess the rapid antidepressant effect of isoflurane by the forced swimming test (FST), the sucrose preference test (SPT), and the novelty suppressed feeding test (NSFT). The protein expression of BDNF and TrkB/protein kinase B (PKB or Akt)/mTOR was determined through Western blot. The dendritic spine density in the hippocampus and medial prefrontal cortex (PFC) was measured by the Golgi staining. RESULTS: A brief burst-suppressing isoflurane anesthesia rapidly reversed the behavioral deficits caused by CUMS procedure, normalized the expression of BDNF and further activated the TrkB signaling pathway in CUMS-induced stressed mice in both prefrontal cortex (PFC) and hippocampus (HC). All of those behavioral and proteomic effects were blocked by K252a, a selective receptor inhibitor of TrkB. Isoflurane significantly promoted the formation of dendritic spines in both medial prefrontal cortex (mPFC), CA1, CA3, and DG of the hippocampus. CONCLUSION: Our study indicates that isoflurane exerts a rapid antidepressant-like effect in CUMS depression animal model, and the activation of BDNF/TrkB signaling pathway plays an indispensable role in the biological and behavioral antidepressant effects of isoflurane. A single exposure to isoflurane could repair synaptic damage caused by chronic stimulation.


Assuntos
Antidepressivos/farmacologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Depressão/metabolismo , Isoflurano/farmacologia , Glicoproteínas de Membrana/metabolismo , Proteínas Tirosina Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Anestésicos Inalatórios/farmacologia , Anestésicos Inalatórios/uso terapêutico , Animais , Antidepressivos/uso terapêutico , Depressão/tratamento farmacológico , Depressão/psicologia , Relação Dose-Resposta a Droga , Isoflurano/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória , Transdução de Sinais/fisiologia , Estresse Psicológico/metabolismo
8.
Technol Cancer Res Treat ; 18: 1533033819854132, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31138033

RESUMO

PURPOSE: Glioma is identified as a broad category of brain and spinal cord tumors. MiR-32 is important in regulating the genesis of different cancers; however, the underlying mechanisms of miR-32 in glioma still largely unknown. This study aimed to elucidate pathobiological functions of miR-32 in glioma and verify its effect on the regulation of enhancer of zeste homolog 2. METHODS: The expression of miR-32 and enhancer of zeste homolog 2 was detected by quantitative real-time polymerase chain reaction and Western blot in glioma tissues and cells. Cell Counting Kit-8 (CCK-8) assay was used to examine the effects of miR-32 on human glioma cells proliferation. Transwell assay was used to examine cell metastasis, respectively. Two bioinformatics analysis software and luciferase reporter assay were chosen to confirm targeting association between miR-32 and enhancer of zeste homolog 2. RESULTS: MiR-32 was downregulated in glioma tissues and cells. Furthermore, enhancer of zeste homolog 2 expression was upregulated and negatively correlated with miR-32 in clinical tissues. Ectopic expression of miR-32 inhibited glioma cell proliferation, migration, and invasion. Enhancer of zeste homolog 2 was identified as direct target gene of miR-32 in glioma. Overexpression of enhancer of zeste homolog 2 ablated the inhibitory effects of miR-32. CONCLUSION: In summary, our finding suggests that miR-32 acts an important role in inhibiting glioma cell proliferation and metastasis and suppresses the expression of ABCC4 by directly targeting its 3'-untranslated region. The miR-32/enhancer of zeste homolog 2 axis may provide new insights to the treatment for glioma.


Assuntos
Proteína Potenciadora do Homólogo 2 de Zeste/genética , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/patologia , MicroRNAs/genética , Interferência de RNA , Regiões 3' não Traduzidas , Adulto , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Genes Reporter , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Adulto Jovem
9.
PLoS One ; 14(4): e0214539, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30947277

RESUMO

China's rapid urbanization and high traffic accident frequency have received many researchers' attention. It is important to reveal how urban infrastructures and other risk factors affects the traffic accident frequency. A growing amount of research has examined the local risk factors impact on traffic accident frequency at certain time. Some studies considered these spatial influences but overlooked the temporal correlation/heterogeneity of traffic accidents and related risk factors. This study explores risk factors' influence on urban traffic accidents frequency while considering both the spatial and temporal correlation/heterogeneity of traffic accidents. The study area is split into 100 equally sized rectangle traffic analysis zones (TAZs), and the urban traffic accident frequency and attributes in each TAZ are extracted. The linear regression model, spatial lag model (SLM), spatial error model (SEM) and time-fixed effects error model (T-FEEM) are established and compared respectively. The proposed methodologies are illustrated using ten-month traffic accident data from the urban area of Guiyang City, China. The results reveal that the time-fixed effects error model, which considers both spatial and temporal correlation/heterogeneity of traffic accidents, is superior to other models. More traffic accidents will happen in those TAZs that have more hospitals or schools. Moreover, hospitals have a greater influence on traffic accidents than schools. Because of the location in the margin of the city, those TAZs that have passenger stations have more traffic accidents. This study provides policy makers with more detailed characterization about the impact of related risk factors on traffic accident frequencies, and it is suggested that not only the spatial correlation/heterogeneity but also the temporal correlation/heterogeneity should be taken into account in guiding traffic accident control of urban area.


Assuntos
Acidentes de Trânsito , Transportes , Algoritmos , China , Cidades , Análise por Conglomerados , Hospitais , Humanos , Modelos Lineares , Análise de Regressão , Reprodutibilidade dos Testes , Fatores de Risco , Instituições Acadêmicas , Fatores de Tempo
10.
IEEE Trans Image Process ; 28(9): 4354-4363, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30872229

RESUMO

Texture filtering seeks to smooth out textured details in order to present structures prominently. To filter out multi-scale textured details while preserving structures, some methods propose to adjust the size of the filtering windows by handling the pixels near structures with small windows and the other pixels with large windows. Unfortunately, their adjustment measures are not very effective in treating complex situations. They may handle the pixels inside small structures with large windows, which overly smooths them, or they may be incapable of smoothing out large-scale textures. With regard to this, in this paper, we present a novel method that adjusts the window size for a pixel by checking similar pixels in its neighborhood. In general, pixels nearer structures have fewer similar pixels in their neighborhoods than the pixels that are farther away from structures. Thus, our adjustment can adaptively adjust window sizes by the distances from pixels to structures, which improves the potential to treat complex situations. The experimental results show that we can well filter out very large-scale textures while preserving small structures with high quality in a manner superior to the state-of-the-art methods. In addition, our method is very simple and efficient, and can be used easily in applications.

11.
Nanoscale Res Lett ; 13(1): 295, 2018 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-30242603

RESUMO

Titanium dioxide (TiO2) nanotube arrays coupled with a narrow gap semiconductor-bismuth selenide (Bi2Se3)-exhibited remarkable enhancement in the photocathodic protection property for 304 stainless steel under visible light. Bi2Se3/TiO2 nanocomposites were successfully synthesized using a simple two-step method, including an electrochemical anodization method for preparing pure TiO2 and a chemical bath deposition method for synthesizing Bi2Se3 nanoflowers. The morphology and structure of the composite films were studied by scanning electron microscopy, energy dispersion spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction. In addition, the influence of the Bi2Se3 content on the photoelectrochemical and photocathodic protection properties of the composite films was also studied. The photocurrent density of the Bi2Se3/TiO2 nanocomposites was significantly higher than that of pure TiO2 under visible light. The sensitizer Bi2Se3 enhanced the efficient separation of the photogenerated electron-hole pairs and the photocathodic protection properties of TiO2. Under visible light illumination, Bi2Se3/TiO2 nanocomposites synthesized by the chemical bath deposition method with Bi3+ (0.5 mmol/L) exhibited the optimal photogenerated cathodic protection performance for 304 stainless steel.

12.
Artigo em Inglês | MEDLINE | ID: mdl-29993979

RESUMO

Texture filtering depends on high-quality texture measurement to separate structures from textures. However, the existing methods employ axis-aligned box windows for texture measurement, which may cover different texture regions, and so lowering the measurement quality because structure edges are not always parallel to the axes. Additionally, the existing texture measurements consider intensity contrast at the pixel level and do not account for the linear characteristics of structure edges in filtering windows; thus, their measurement effectiveness is limited. This results in a dilemma for texture filtering. Large-scale textures are not smoothed using smaller windows, while small structures are removed using larger windows. In this paper, we present edge-aware measures to improve texture measurement. Edge-aware windows are constructed such that each window is inside a texture region to the greatest extent possible, and the linear characteristics of structure edges are accounted for in the texture measurement. Furthermore, we use large box windows for texture filtering and long and narrow edge-aware small windows for texture measurement to filter out large-scale textures while preserving small structures. The experimental results show improved texture filtering with our method compared with existing methods.

13.
J Int Med Res ; 46(1): 158-167, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28758851

RESUMO

Objective To identify potential genes that may be involved in lipid metabolism in rats after treatment with aqueous extract of Arctium lappa L (burdock). Methods Rats were randomly divided into six groups: (i) control (standard diet); (ii) model group (high-fat diet only); (iii) high-fat diet and low-dose aqueous burdock root extract (2 g/kg); (iv) high-fat diet and moderate-dose aqueous burdock root extract (4 g/kg); (v) high-fat diet and high-dose aqueous burdock root extract (8 g/kg); and (vi) a positive control group exposed to a high-fat diet and simvastatin (10 mg/kg). Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was performed to find the potential candidate genes involved in the modulation of blood lipids by treatment with aqueous burdock root extract. Results Burdock root extract reduced body weight and cholesterol levels in rats. KEGG analysis revealed 113 genes that were involved in metabolic pathways. Of these, 27 potential genes associated with blood lipid metabolism were identified. Conclusions Aqueous extract of burdock root reduced body weight and cholesterol in rats, possibly by modulating the differential expression of genes.


Assuntos
Arctium/química , Dieta Hiperlipídica , Regulação da Expressão Gênica , Hipolipemiantes/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Enciclopédias como Assunto , Perfilação da Expressão Gênica , Ontologia Genética , Hipolipemiantes/química , Metabolismo dos Lipídeos/genética , Masculino , Anotação de Sequência Molecular , Extratos Vegetais/química , Raízes de Plantas/química , Ratos , Ratos Sprague-Dawley , Sinvastatina/farmacologia , Solventes/química , Triglicerídeos/sangue , Água/química
14.
Physiol Plant ; 163(1): 45-58, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29055043

RESUMO

Salinity significantly limits leaf photosynthesis but the factors causing the limitation in salt-stressed leaves remain unclear. In the present work, photosynthetic and biochemical traits were investigated in four rice genotypes under two NaCl concentration (0 and 150 mM) to assess the stomatal, mesophyll and biochemical contributions to reduced photosynthetic rate (A) in salt-stressed leaves. Our results indicated that salinity led to a decrease in A, leaf osmotic potential, electron transport rate and CO2 concentrations in the chloroplasts (Cc ) of rice leaves. Decreased A in salt-stressed leaves was mainly attributable to low Cc , which was determined by stomatal and mesophyll conductance. The increased stomatal limitation was mainly related to the low leaf osmotic potential caused by soil salinity. However, the increased mesophyll limitation in salt-stressed leaves was related to both osmotic stress and ion stress. These findings highlight the importance of considering mesophyll conductance when developing salinity-tolerant rice cultivars.


Assuntos
Dióxido de Carbono/metabolismo , Oryza/fisiologia , Fotossíntese/fisiologia , Cloroplastos/fisiologia , Difusão , Células do Mesofilo/fisiologia , Osmose , Folhas de Planta/fisiologia , Estômatos de Plantas/fisiologia , Salinidade , Cloreto de Sódio/metabolismo , Solo/química , Estresse Fisiológico
15.
Front Plant Sci ; 8: 1369, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28848573

RESUMO

Remobilisation of non-structural carbohydrates (NSC) from leaves and stems and unloading into developing grains are essential for yield formation of rice. In present study, three recombinant inbred lines of rice, R91, R156 and R201 have been tested for source-flow-sink related attributes determining the nature of NSC accumulation and translocation at two nitrogen levels in the field. Compared to R91 and R156, R201 had lower grain filling percentage, harvest index, and grain yield. Meanwhile, R201 had significantly lower stem NSC translocation during grain filling stage. Grain filling percentage, harvest index, and grain yield showed the consistent trend with stem NSC translocation among the three lines. In comparison with R91 and R156, R201 had similarity in leaf area index, specific leaf weight, stem NSC concentration at heading, biomass, panicles m-2, spikelets per panicle, remobilization capability of assimilation in stems, sink capacity, sink activity, number and cross sectional area of small vascular bundles, greater number and cross sectional area of large vascular bundles, and higher SPAD, suggesting that source, flow, and sink were not the limiting factors for low stem NSC translocation and grain filling percentage of R201. However, R201 had significant higher stem and rachis NSC concentrations at maturity, which implied that unloading in the developing grains might result in low NSC translocation in R201. The results indicate that stem NSC translocation could be beneficial for enhancement of grain yield potential, and poor unloading into caryopsis may be the possible cause of low stem NSC translocation, poor grain filling and yield formation in R201.

16.
Int J Mol Sci ; 18(6)2017 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-28594376

RESUMO

Perfluorooctanoic acid (PFOA) is an environmental contaminant that could induce developmental cardiotoxicity in a chicken embryo, which may be alleviated by l-carnitine. To explore the roles of reactive oxygen species (ROS) and nitric oxide (NO) in such changes and the potential effects of l-carnitine, fertile chicken eggs were exposed to PFOA via an air cell injection, with or without l-carnitine co-treatment. The ROS and NO levels in chicken embryo hearts were determined with electron spin resonance (ESR), and the protein levels of the nuclear factor κ-light chain-enhancer of activated B cells (NF-κB) p65 and inducible nitric oxide synthase (iNOS) in chicken embryo hearts were assessed with western blotting. The results of ESR indicated that PFOA exposure induced an elevation in the ROS levels in ED19 chicken embryo hearts and hatchling chicken hearts, while l-carnitine could alleviate such changes. Meanwhile, increased NO levels were observed in ED19 embryo hearts and hatchling hearts following PFOA exposure, while l-carnitine co-treatment exerted modulatory effects. Western blotting revealed that p65 translocation in ED19 embryo hearts and hatchling hearts was enhanced by PFOA, while l-carnitine co-treatment alleviated such changes. iNOS expression levels in ED19 embryo hearts followed the same pattern as NO levels, while a suppression of expression was observed in hatchling hearts exposed to PFOA. ROS/NF-κB p65 and iNOS/NO seem to be involved in the late stage (ED19 and post hatch) of PFOA-induced developmental cardiotoxicity in a chicken embryo. l-carnitine could exert anti-oxidant and NO modulatory effects in the developing chicken embryo hearts, which likely contribute to its cardioprotective effects.


Assuntos
Caprilatos/efeitos adversos , Cardiotônicos/farmacologia , Cardiotoxicidade/etiologia , Cardiotoxicidade/metabolismo , Carnitina/farmacologia , Fluorcarbonetos/efeitos adversos , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Cardiotoxicidade/prevenção & controle , Embrião de Galinha , Coração/efeitos dos fármacos , Frequência Cardíaca , Óxido Nítrico Sintase Tipo II/metabolismo , Fator de Transcrição RelA/metabolismo
17.
J Hazard Mater ; 338: 66-75, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28531660

RESUMO

Carbon black nanoparticles (CBNs) have been associated with the progression of atherosclerosis. CBNs normally enter the bloodstream and crosslink together to form agglomerates. However, most studies have used nano-sized CB particles to clarify the involvement of CBN exposure in CBN-induced endothelial dysfunction. Herein, we studied endothelial toxicity of CBN aggregates (CBA) to human EA.hy926 vascular cells. Cell viability, lactate dehydrogenase leakage, and oxidative stress were affected by the highest concentration of CBA. Moreover, transmission electron microscopic results showed that CBA entered cells through membrane enclosed vesicles. Rho-associated kinase (ROCK) is involved in regulating vascular diseases. Thus, we co-treated with the of ROCK inhibitor Y-27632 to study whether other adverse effects caused by CBA are related to activating ROCK. As expected, co-treatment with Y-27632 attenuated CBA-induced cytoskeletal damage, dysfunction of the endothelial barrier, and expression of inflammatory factors. Taken together, these results demonstrate that aggregated CBNs can cause endothelial dysfunction possibly by activating ROCK.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Fuligem/toxicidade , Quinases Associadas a rho/metabolismo , Actinas/metabolismo , Amidas/toxicidade , Aterosclerose/patologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citoesqueleto/efeitos dos fármacos , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Ativação Enzimática , Humanos , L-Lactato Desidrogenase/metabolismo , Microscopia Eletrônica de Transmissão , Estresse Oxidativo , Inibidores de Proteínas Quinases/toxicidade , Piridinas/toxicidade , Cicatrização/efeitos dos fármacos
18.
Sci Total Environ ; 599-600: 1658-1666, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28535594

RESUMO

According to the Chinese Ministry of Health, industrial pollution-induced health impacts have been the leading cause of death in China. While industrial fine particulate matter (PM2.5) is associated with adverse health effects, the major action mechanisms of different compositions of PM2.5 are currently unclear. In this study, we treated normal human lung epithelial BEAS-2B cells with industrial organic and water-soluble PM2.5 extracts under daily alveolar deposition dose to elucidate the molecular mechanisms underlying adverse pulmonary effects induced by PM2.5, including oxidative damage, inflammatory response, lung epithelial barrier dysfunction, and the recruitment of macrophages. We found that water-soluble PM2.5 extracts caused more severe cytotoxic effects on BEAS-2B cells compared with that of organic extracts. Both organic and water-soluble PM2.5 extracts induced activation of the RhoA/ROCK pathway. Inflammatory response, epithelial barrier dysfunction, and the activation of NF-кB caused by both PM2.5 extracts were attenuated by ROCK inhibitor Y-27632. This indicated that both PM2.5 extracts could cause damage to epithelial cells through RhoA/ROCK-dependent NF-кB activation. Furthermore, the upregulation of macrophage adhesion induced by both PM2.5 extracts was also attenuated by Y-27632 in a co-culture model of macrophages and the epithelial cells. Therefore, our results support that industrial PM2.5 extracts-induced activation of the RhoA/ROCK-dependent NF-кB pathway induces pulmonary adverse effect. Thus, pharmacological inhibition of ROCK activation might have therapeutic potential in preventing lung disease associated with PM2.5.

19.
Front Plant Sci ; 8: 371, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28367158

RESUMO

Cytokinins (CTKs) regulate panicle size and mediate heat tolerance in crops. To investigate the effect of high temperature on panicle CTK expression and the role of such expression in panicle differentiation in rice, four rice varieties (Nagina22, N22; Huanghuazhan, HHZ; Liangyoupeijiu, LYPJ; and Shanyou63, SY63) were grown under normal conditions and subjected to three high temperature treatments and one control treatment in temperature-controlled greenhouses for 15 days during the early reproductive stage. The high temperature treatments significantly reduced panicle CTK abundance in heat-susceptible LYPJ, HHZ, and N22 varieties, which showed fewer spikelets per panicle in comparison with control plants. Exogenous 6-benzylaminopurine application mitigated the effect of heat injury on the number of spikelets per panicle. The high temperature treatments significantly decreased the xylem sap flow rate and CTK transportation rate, but enhanced cytokinin oxidase/dehydrogenase (CKX) activity in heat-susceptible varieties. In comparison with the heat-susceptible varieties, heat-tolerant variety SY63 showed less reduction in panicle CTK abundance, an enhanced xylem sap flow rate, an improved CTK transport rate, and stable CKX activity under the high temperature treatments. Enzymes involved in CTK synthesis (isopentenyltransferase, LONELY GUY, and cytochrome P450 monooxygenase) were inhibited by the high temperature treatments. Heat-induced changes in CTK transportation from root to shoot through xylem sap flow and panicle CTK degradation via CKX were closely associated with the effects of heat on panicle CTK abundance and panicle size. Heat-tolerant variety SY63 showed stable panicle size under the high temperature treatments because of enhanced transport of root-derived CTKs and stable panicle CKX activity. Our results provide insight into rice heat tolerance that will facilitate the development of rice varieties with tolerance to high temperature.

20.
Colloids Surf B Biointerfaces ; 153: 300-309, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28285061

RESUMO

The biocompatibilities of graphene-family nanomaterials (GFNs) should be thoroughly evaluated before their application in drug delivery and anticancer therapy. The present study aimed to consecutively assess the immunotoxicity of graphene oxide nanoplatelets (GONPs) and reduced GONPs (rGONPs) on THP-1 cells, a human acute monocytic leukemia cell line. GONPs induced the expression of antioxidative enzymes and inflammatory factors, whereas rGONPs had substantially higher cellular uptake rate, higher levels of NF-κB expression. These distinct toxic mechanisms were observed because the two nanomaterials differ in their oxidation state, which imparts different affinities for the cell membrane. Because GONPs have a higher cell membrane affinity and higher impact on membrane proteins compared with rGONPs, macrophages (THP-1a) derived from GONPs treated THP-1cells showed a severer effect on phagocytosis. By consecutive evaluation the effects of GONPs and rGONPs on THP-1 and THP-1a, we demonstrated that their surface oxidation states may cause GFNs to behave differently and cause different immunotoxic effects.


Assuntos
Materiais Biocompatíveis/farmacologia , Grafite/farmacologia , Monócitos/efeitos dos fármacos , Nanoestruturas/química , Óxidos/farmacologia , Materiais Biocompatíveis/química , Diferenciação Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Grafite/química , Humanos , Monócitos/imunologia , Monócitos/patologia , Oxirredução , Óxidos/química , Espécies Reativas de Oxigênio/imunologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
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