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1.
J Environ Manage ; 354: 120323, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38417356

RESUMO

Accumulation of persistent organic pollutants polycyclic aromatic hydrocarbons (PAHs) in soil has become a global problem. Composting is considered one of the more economical methods of soil remediation and is important for the resourceful use of wastes. Agroforestry waste is produced in huge amounts and is utilized at low rates, hence there is an urgent need to manage it. Here, leaf (LVS) or rice straw (SVS) was co-composting with aged contaminated soil to investigate bacteria interaction to PAHs degradation and humus formation. The degradation rate of high molecular weight PAHs (HMW-PAHs) in LVS and SVS reached 58.9% and 52.5%, and the low molecular weight PAHs (LMW-PAHs) were 77.5% and 65%. Meanwhile, the humus increased by 44.8% and 60.5% in LVS and SVS at the end of co-composting. The topological characteristics and community assembly of the bacterial community showed that LVS had higher complexity and more keystones than SVS, suggesting that LVS might more beneficial for the degradation of PAHs. The stability of the co-occurrence network and stochastic processes (dispersal limitation) dominated community assembly made SVS beneficial for humus formation. Mantel test and structural equation models indicated that the transformation of organic matter was important for PAHs degradation and humus formation. Degradation of HMW-PAHs led to bacterial succession, which affected the formation of precursors and ultimately increased the humus content. This study provided potential technology support for improving the quality of agroforestry organic waste composting and degrading PAHs in aged contaminated soil.


Assuntos
Compostagem , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Biodegradação Ambiental , Poluentes do Solo/análise , Solo/química , Bactérias/metabolismo , Microbiologia do Solo
2.
J Environ Manage ; 326(Pt B): 116852, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36435124

RESUMO

To solve polycyclic aromatic hydrocarbons (PAHs) pollution, composting was chosen as a remediation method. During composting, the dissipation of PAHs was carried out by resource utilization of organic solid waste and its degradation by bacteria. This study was conducted by co-composting with contaminated soil and cow manure. The results showed that the degradation rates of naphthalene (Nap), phenanthrene (Phe), and benzo[α]pyrene (BaP) could reach 82.2%, 79.4%, and 59.6% respectively during composting. Cluster analysis indicated that polyphenol oxidase (PPO), laccase, and protease were important drivers of PAHs transformation. The content of humic substances (HS) was 106.67 g/kg in PAH treatment, which was significantly higher than that in the control group at 65 days. The phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) and network analysis was used to infer the degradation mechanism of PAHs by microorganisms. The degradation of PAHs by PPO was found to have a significant contribution to the formation of HS. It was shown that PAHs and metabolic intermediates were more inclined to be oxidized and decomposed by PPO to form quinone, which in turn condensed with amino acids to form HS. Composting could promote the degradation of PAHs while improving the quality of compost, achieving a win-win situation.


Assuntos
Compostagem , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Animais , Bovinos , Solo/química , Hidrocarbonetos Policíclicos Aromáticos/química , Esterco , Filogenia , Poluentes do Solo/análise , Biodegradação Ambiental , Bactérias/metabolismo , Substâncias Húmicas
3.
Ophthalmology ; 129(2): 209-219, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34536465

RESUMO

PURPOSE: This study attempted to estimate the impact of eye-preserving therapies for the long-term prognosis of patients with advanced retinoblastoma with regard to overall survival and ocular salvage. DESIGN: Retrospective cohort study covering all 31 provinces (38 retinoblastoma treating centers) of mainland China. PARTICIPANTS: One thousand six hundred seventy-eight patients diagnosed with group D or E retinoblastoma from January 2006 through May 2016. METHODS: Chart review was performed. The patients were divided into primary enucleation and eye-preserving groups, and they were followed up for survival status. The impact of initial treatment on survival was evaluated by Cox analyses. MAIN OUTCOME MEASURES: Overall survival and final eye preservation. RESULTS: After a median follow-up of 43.9 months, 196 patients (12%) died, and the 5-year overall survival was 86%. In total, the eyeball preservation rate was 48%. In this cohort, 1172 patients (70%) had unilateral retinoblastoma, whereas 506 patients (30%) had bilateral disease. For patients with unilateral disease, 570 eyes (49%) underwent primary enucleation, and 602 patients (51%) received eye-preserving therapies initially. During the follow-up (median, 45.6 months), 59 patients (10%) from the primary enucleation group and 56 patients (9.3%) from the eye-preserving group died. Multivariate Cox analyses indicated no significant difference in overall survival between the 2 groups (hazard ratio [HR], 1.25; 95% confidence interval [CI], 0.85-1.84; P = 0.250). For patients with bilateral disease, 95 eyes (19%) underwent primary enucleation, and 411 patients (81%) received eye-preserving therapies initially. During the follow-up (median, 40.1 months), 12 patients (13%) from the primary enucleation group and 69 patients (17%) from the eye-preserving group died. For bilateral retinoblastoma with the worse eye classified as group E, patients undergoing primary enucleation exhibited better overall survival (HR, 2.35; 95% CI, 1.10-5.01; P = 0.027); however, this survival advantage was not evident until passing 22.6 months after initial diagnosis. CONCLUSIONS: Eye-preserving therapies have been used widely for advanced retinoblastoma in China. Patients with bilateral disease whose worse eye was classified as group E and who initially underwent eye-preserving therapies exhibited a worse overall survival. The choice of primary treatment for advanced retinoblastoma should be weighed carefully.


Assuntos
Neoplasias da Retina/terapia , Retinoblastoma/terapia , Terapia de Salvação , Antineoplásicos/uso terapêutico , Braquiterapia , Pré-Escolar , China , Terapia Combinada , Crioterapia , Enucleação Ocular , Feminino , Seguimentos , Humanos , Lactente , Fotocoagulação a Laser , Masculino , Neoplasias da Retina/mortalidade , Neoplasias da Retina/patologia , Retinoblastoma/mortalidade , Retinoblastoma/patologia , Estudos Retrospectivos , Taxa de Sobrevida
4.
Phys Chem Chem Phys ; 23(45): 25590-25596, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34783799

RESUMO

The twinning plane of crystals with a face-centered-cubic (FCC) structure is usually the (111) plane, as found in FCC metals and oxides with FCC sublattices of oxygen, like rock-salt-type NiO and spinel-type Fe3O4. Surprisingly, we found in this work that the twinning plane of rock-salt-type CoO is the (112) plane, although Co is adjacent to Ni in the periodic table. The atomic and electronic structures of the CoO(112) twin boundary with in-plane shift vector 1/2[111] have been studied combining aberration-corrected scanning transmission electron microscopy (STEM), electron-energy-loss spectroscopy (EELS), and density functional theory (DFT) calculations. It was found that the atoms at the twin boundary have nominal oxidation states, and the twin boundary remains insulating and antiferromagnetically coupled. Importantly, through the electronic structures and the crystal orbital Hamilton population (COHP) analyses, the (112) twin boundary is found to be more stable than the (111) twin boundary.

5.
Sci Bull (Beijing) ; 69(4): 466-472, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38161093

RESUMO

Antiferromagnetic imaging is critical for understanding and optimizing the properties of antiferromagnetic materials and devices. Despite the widespread use of high-energy electrons for atomic-scale imaging, they have low sensitivity to spin textures. Typically, the magnetic contribution to the phase of a high-energy electron wave is weaker than one percent of the electrostatic potential. Here, we demonstrate direct imaging of antiferromagnetic lattice through precise phase retrieval via electron ptychography, paving the way for magnetic lattice imaging of antiferromagnetic materials and devices.

6.
Nat Nanotechnol ; 19(5): 612-617, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38286877

RESUMO

Technical advances paired with developments in methodology have enabled electron microscopy to reach atomic resolution. Further improving the information limit in microscopic imaging requires further improvements in methodology. Here we report a ptychographic method that describes the object as the sum of discrete atomic-orbital-like functions (for example, Gaussian functions) and the probe in terms of aberration functions. Using this method, we realize an improved information limit of microscopic imaging, reaching down to 14 pm. High-quality probes and objects contribute to superior signal-to-noise ratios at low electron doses, allowing for relaxation of the sample thickness restriction to 50 nm for dense materials. Additionally, our method has the capability to decompose the total phase into element components, revealing that the information limit is element dependent. With enhanced spatial resolution, signal-to-noise ratio and thickness threshold compared with conventional ptychography methods, our local-orbital ptychography may find applications in atomic-resolution imaging of metals, ceramics, electronic devices or beam-sensitive material.

7.
Nat Commun ; 15(1): 2605, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38521797

RESUMO

Nonlinear transport enabled by symmetry breaking in quantum materials has aroused considerable interest in condensed matter physics and interdisciplinary electronics. However, achieving a nonlinear optical response in centrosymmetric Dirac semimetals via defect engineering has remained a challenge. Here, we observe the helicity dependent terahertz emission in Dirac semimetal PtTe2 thin films via the circular photogalvanic effect under normal incidence. This is activated by a controllable out-of-plane Te-vacancy defect gradient, which we unambiguously evidence with electron ptychography. The defect gradient lowers the symmetry, which not only induces the band spin splitting but also generates the giant Berry curvature dipole responsible for the circular photogalvanic effect. We demonstrate that the THz emission can be manipulated by the Te-vacancy defect concentration. Furthermore, the temperature evolution of the THz emission features a minimum in the THz amplitude due to carrier compensation. Our work provides a universal strategy for symmetry breaking in centrosymmetric Dirac materials for efficient nonlinear transport.

8.
J Int Med Res ; 51(12): 3000605231218634, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38149433

RESUMO

Dermoid cysts are one of the most common benign orbital tumours in children and usually occur unilaterally. Bilateral dermoid cysts in the orbit are rare. We report here, a case of bilateral orbital dermoid cysts, in a 29-month-old baby girl. The patient's prognosis was favourable following surgical resection. Through this case report, we hope to increase the recognition and understanding of this condition.


Assuntos
Cisto Dermoide , Neoplasias Orbitárias , Criança , Lactente , Feminino , Humanos , Pré-Escolar , Cisto Dermoide/diagnóstico por imagem , Cisto Dermoide/cirurgia , Neoplasias Orbitárias/diagnóstico por imagem , Neoplasias Orbitárias/cirurgia , Neoplasias Orbitárias/patologia , Órbita/patologia
9.
Nat Commun ; 14(1): 162, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36631462

RESUMO

Defects in crystals play a fundamental role in modulating mechanical, electrical, luminescent, and magnetic behaviors of materials. However, accurate measurement of defect structures is hindered by symmetry breaking and the corresponding complex modifications in atomic configuration and/or crystal tilt at the defects. Here, we report the deep-sub-angstrom resolution imaging of dislocation cores via multislice electron ptychography with adaptive propagator, which allows sub-nanometer scale mapping of crystal tilt in the vicinity of dislocation cores and simultaneous recovery of depth-dependent atomic structure of dislocations. The realization of deep-sub-angstrom resolution and depth-dependent imaging of defects shows great potential in revealing microstructures and properties of real materials and devices.

10.
Adv Mater ; 35(13): e2209941, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36621778

RESUMO

Interstitial solutes, such as carbon in steels, are effective solid-solution hardening agents. These alloying elements are believed to occupy the octahedral interstices in body-centered-cubic (bcc) metals. Using deep-sub-angstrom-resolution electron ptychography, here the first experimental evidence to directly observe individual oxygen atoms in a highly concentrated bcc solid solution-the (TiNbZr)86 O12 C1 N1 medium-entropy alloy (MEA)-is provided, whereby the interstitial sites in which the oxygen atoms are located are discerned. In addition to oxygen interstitials residing in octahedral sites, the first unambiguous evidence of a switch in preference to the unusual tetrahedral sites at high oxygen concentrations is shown. This shift away from octahedral occupancy is explained as resulting from the extra cost of strain energy when the requisite displacement of the host atoms is deterred in the presence of nearby octahedral interstitials.

11.
Sci Adv ; 9(11): eadf1151, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36921047

RESUMO

Sub-angstrom resolution imaging of porous materials like zeolites is important to reveal their structure-property relationships involved in ion exchange, molecule adsorption and separation, and catalysis. Using multislice electron ptychography, we successfully measured the atomic structure of zeolite at sub-angstrom lateral resolution for 100-nanometer-thick samples. Both lateral and depth deformations of the straight channels are mapped, showing the three-dimensional structural inhomogeneity and flexibility. Since most zeolites in industrial applications are usually tens to hundreds of nanometers thick, the sub-angstrom resolution imaging and accurate measurements of depth-dependent local structures with electron ptychography at low-dose condition will find wide applications in porous materials close to their industrially relevant conditions.

12.
J Hazard Mater ; 458: 132032, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37451101

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are a cluster of highly hazardous organic pollutants that are widespread in ecosystems and threaten human health. Composting has been shown to be an effective strategy for PAHs degredation. Here, we used Comamonas testosteroni as an inoculant in composting and investigated the potential mechanisms of PAHs degradation by co-occurrence network and structural equation modelling analysis. The results showed that more than 60% of PAHs were removed and the bacterial community responded to the negative effects of PAHs by upgrading the network. Inoculation with C. testosteroni altered bacterial community succession, intensified bacterial response to PAHs, improved metabolic activity, and promoted the degradation of PAHs during co-composting. The increased in the positive cohesion index of the community suggested that agents increased the cooperative behaviour between bacteria and led to changes in keystones of the bacterial network. However, the topological values of C. testosteroni in the network were not elevated, which confirmed that C. testosteroni altered communities by affecting other bacterial growth rather than its own colonisation. This study strengthens our comprehension of the potential mechanisms for the degradation of PAHs in inoculated composting.


Assuntos
Comamonas testosteroni , Compostagem , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Comamonas testosteroni/metabolismo , Ecossistema , Biodegradação Ambiental , Bactérias/metabolismo , Poluentes do Solo/metabolismo , Solo/química , Microbiologia do Solo
13.
Sci Adv ; 8(19): eabn2275, 2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35559675

RESUMO

Superresolution imaging of solids is essential to explore local symmetry breaking and derived material properties. Electron ptychography is one of the most promising schemes to realize superresolution imaging beyond aberration correction. However, to reach both deep sub-angstrom resolution imaging and accurate measurement of atomic structures, it is still required for the electron beam to be nearly parallel to the zone axis of crystals. Here, we report an efficient and robust method to correct the specimen misorientation in electron ptychography, giving deep sub-angstrom resolution for specimens with large misorientations. The method largely reduces the experimental difficulties of electron ptychography and paves the way for widespread applications of ptychographic deep sub-angstrom resolution imaging.

14.
Environ Sci Pollut Res Int ; 29(54): 82351-82364, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35750914

RESUMO

Bioremediation is a promising method of treating polycyclic aromatic hydrocarbons (PAHs) in contaminated soil; however, the understanding of the efficiency and the way of microbial inoculants work in complex soil environments is limited. Comamonas testosteroni (Ct) strains could efficiently degrade PAHs, especially naphthalene (Nap) and phenanthrene (Phe). This study aimed to explore the functional role of Ct in soil indigenous microorganisms and analyze the effect of Ct addition on PAHs concentration in PAH-contaminated soil. The results showed that inoculation with Ct degraded naphthalene (Nap), phenanthrene (Phe), and benzo [α] pyrene (BaP) significantly; the degradation rates were 63.38%, 81.18%, and 37.98% on day 25, respectively, suggesting that the low molecular weights of Nap and Phe were more easily degraded by microorganisms than those of BaP. We speculated that BaP and Phe might be converted into Nap for further degradation, which is the main reason for the low degradation rate of Nap detected after 10-25 days. Network analysis showed that inoculation with Ct significantly increased bacteria community abundance closely related to PAHs. Structural equation models confirmed that Steroidobacter, as functional bacteria, could affect the degradation of Nap and BaP. Inoculated Ct effectively enhanced the synergy among indigenous bacteria to degrade PAHs. This finding will help understand the function of inoculated Ct strains in PAH-contaminated soil at the laboratory level.


Assuntos
Comamonas testosteroni , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Biodegradação Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Solo , Comamonas testosteroni/metabolismo , Microbiologia do Solo , Poluentes do Solo/análise , Bactérias/metabolismo , Fenantrenos/análise , Naftalenos/análise , Pirenos/análise
15.
Am J Ophthalmol ; 236: 193-203, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34626572

RESUMO

PURPOSE: To report three-decade changes of clinical characteristics, progress of treatments, and risk factors associated with mortality and enucleation in patients with retinoblastoma in China. DESIGN: Retrospective cohort study. METHODS: This multicenter study included 2552 patients diagnosed with retinoblastoma in 38 medical centers in 31 provinces in China from 1989 to 2017, with follow-up data. Kendall's tau-b value was used to describe correlation coefficients between the three eras (between 1989 and 2008, between 2009 and 2013, and between 2014 and 2017) and clinical or demographic features. Hazard ratios and odds ratios were applied to measure risk factors. RESULTS: A total of 324 (13%) patients died and 1414 (42%) eyes were removed. The 1-year, 3-year, and 5-year overall survival rates were 95%, 86%, and 83%, respectively. Patients were diagnosed at a better stage by International Classification for Retinoblastoma over time (Kendall's tau-b value = -0.084, P < .001). Pathological risk factors were also observed less in recent eras. New conservative therapies were adopted and used in more patients. The eye removal rate gradually decreased (Kendall's tau-b value = -0.167, P < .001). The overall survival rates were 81%, 83%, and 91% in the three eras. By multivariate Cox regression, bilateral tumors and extraocular extension were identified as risk factors for death. Among intraocular disease, Group E indicated higher risk of mortality. By multivariate logistics regression, unilateral tumors, earlier era of diagnosis, and extraocular extension were risk factors for eye salvage failure. Among intraocular retinoblastoma, Groups D and E had higher risk of eye salvage failure. CONCLUSIONS: Patients were diagnosed at an earlier stage in recent eras. Conservative therapies, including intra-arterial chemotherapy, were increasingly being used. The above changes may contribute to the decreasing enucleation rate. Although no significant impact was identified on the mortality by the three eras, a decreasing trend was shown.


Assuntos
Neoplasias da Retina , Retinoblastoma , Enucleação Ocular , Humanos , Lactente , Neoplasias da Retina/diagnóstico , Neoplasias da Retina/epidemiologia , Neoplasias da Retina/terapia , Retinoblastoma/diagnóstico , Retinoblastoma/epidemiologia , Retinoblastoma/terapia , Estudos Retrospectivos , Terapia de Salvação
16.
Exp Eye Res ; 90(2): 324-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19941853

RESUMO

Vascular peripheral resistance is increased during hypertension, and endothelium-derived hyperpolarizing factor (EDHF) is an important for regulating vasodilation in small arteries. Therefore we characterized the role of EDHF in regulating vascular resistance of ocular ciliary arteries from spontaneous hypertensive rats (SHR) and age-matched Wistar Kyoto rats (WKY). Isometric tension recordings were used in isolated ocular ciliary artery segments from SHR and WKY. Ocular ciliary arteries pre-contracted with 100 microM norepinephrine exhibited a concentration-dependent relaxation to acetylcholine, and the effect on SHR arteries was smaller than that on WKY arteries (P < 0.05). The EDHF-mediated component of this relaxation, determined in the presence of 100 microM l-NAME plus 10 microM indomethacin, was also smaller in SHR than in WKY arteries (P < 0.05). Apamin (1 microM), a blocker of small-conductance calcium-activated K(+) (K(Ca)) channels, had no effect on EDHF-mediated relaxation in either preparation. However, charybdotoxin (0.1 microM), which blocks intermediate- and large-conductance K(Ca) channels, and iberiotoxin (0.1 microM), which blocks large-conductance K(Ca) channels, almost completely suppressed EDHF-mediated relaxation in both preparations. The tension of ciliary arteries from both SHR and WKY was increased above baseline by 100 microM l-NAME plus 10 microM indomethacin. In these preparations, apamin had no effect on the tension in arteries from either SHR or WKY. However, both charybdotoxin and iberiotoxin further increased tension above that induced by l-NAME and indomethacin. The increase was smaller for SHR than WKY (P < 0.05). In summary, the ability of EDHF to relax ocular ciliary artery vascular tone in SHR is smaller than in WKY. The large-conductance calcium-activated K(+) channel is utilized in EDHF-signaling pathway.


Assuntos
Fatores Biológicos/fisiologia , Artérias Ciliares/fisiologia , Endotélio Vascular/fisiologia , Hipertensão/fisiopatologia , Músculo Liso Vascular/fisiologia , Acetilcolina/farmacologia , Animais , Pressão Sanguínea , Relação Dose-Resposta a Droga , Frequência Cardíaca , Contração Isométrica/efeitos dos fármacos , Masculino , Norepinefrina/farmacologia , Canais de Potássio Cálcio-Ativados/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Resistência Vascular/fisiologia , Vasodilatação/fisiologia
17.
Sheng Wu Gong Cheng Xue Bao ; 36(12): 2657-2673, 2020 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-33398962

RESUMO

To investigate the degradation of polycyclic aromatic hydrocarbons (PAHs) and the changes of rhizosphere microorganisms in the rhizosphere soil of Leymus chinensis during the remediation of PAHs contaminated soil by Comamonas testosteroni (C.t)-assisted Leymus chinensis, we evaluated the removal of PAHs in the rhizosphere of Leymus chinensis using gas chromatography-mass spectrometry (GC-MS), analyzed the bacterial community and the diversity in Leymus chinensis rhizosphere soil by high-throughput sequencing technology, characterized the correlation among PAHs degradation and bacterial community components performing redundancy analysis (RDA) and network analysis, and predicted PAHs degradation potential via PICRUSt software in this paper. The degradation of PAHs in the rhizosphere of Leymus chinensis was promoted, the abundance and diversity of bacteria and the correlation among bacteria and PAHs were changed, and the degradation potential of PAHs in Leymus chinensis rhizosphere soil was enhanced in the later stage of phytoremediation (60-120 d) due to the incorporation of C.t. The accelerated degradation of three PAHs (Nap, Phe, BaP) was accompanied by the differ abundance and correlation of Proteobacteria (Sphingomonas, MND1, Nordella), Actinomycetes (Rubrobacter, Gaiella), Acidobacteria (RB41) and Bacteroides (Flavobacterium) affected by C.t. The results provide new insight into the microorganism choices for microbial assisted plant remediation of soil PAHs and the mechanisms of enhanced PAHs degradation via the combination of Comamonas testosteroni engineering bacteria and plants.


Assuntos
Comamonas testosteroni , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Biodegradação Ambiental , Comamonas testosteroni/genética , Hidrocarbonetos Policíclicos Aromáticos/análise , Rizosfera , Solo , Microbiologia do Solo
18.
Int J Ophthalmol ; 12(3): 363-368, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30918801

RESUMO

AIM: To investigate the alterations in both structure and contractile responsiveness of ocular ciliary artery (OCA) in spontaneously hypertensive rat (SHR). METHODS: In this experiment, 20-week-old male SHR and Wistar Kyoto rat (WKY) were studied. The heart rate (HR), the blood pressure (BP; the systolic BP and the diastolic BP) of rats with an electronic sphygmomanometer were measured. Vascular morphometry and isometric tension measurement were used to investigate the alterations in structure and contractility of OCA. RESULTS: A general narrowing of OCAs was observed in SHR compared to the control WYK. In SHR, the media of OCAs were thicker, the luminal diameters were smaller, and the media-to-lumen ratios were higher when compared with WKY (P<0.05). The contractions of OCAs evoked by norepinephrine were smaller in SHR compared to control (P<0.05). Then, OCAs were pretreated with iberiotoxin, L-NAME, or indomethacin 30min before norepinephrine-induced contraction. Iberiotoxin (0.1 µmol/L) has not changed the norepinephrine-induced contractions in OCAs from both groups. However, L-NAME (100 µmol/L) increased the vasoconstrictions, the increased extents were similar in SHR and WKY (P>0.05). Indomethacin (10 µmol/L) decreased the contractions induced by norepinephrine in OCAs from WKY (P<0.05), but did not change those contractions in vessels from SHR (P>0.05). CONCLUSION: Our results demonstrate that the structure and function of OCAs are altered in hypertension. OCAs from SHR are remodeled with decreased lumen diameter and increased media-to-lumen ratio. Moreover, the contractile responsiveness of OCAs from SHR is diminished due to the disruption of vasoconstrictive effect of prostaglandins.

19.
Environ Sci Pollut Res Int ; 26(24): 25071-25083, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31250394

RESUMO

As the largest oil field in China, Daqing oil field has been developed in the past six decades. The objectives of this study were to measure the levels of polycyclic aromatic hydrocarbons (PAHs) and assess their ecological risk of PAHs in vegetation soil and bare soil near oil well in Daqing and surrounding soil. Ten sites were selected from two types of soil in grassland: vegetation soil (VS, n = 5) and bare soil (BS, n = 5). The mean concentration of 16 PAHs (∑16 PAHs) was 2240.2 µg/kg. The mean concentrations of eight carcinogenic PAHs (∑8c PAHs) was 1312.3 µg/kg which accounts for 59% of ∑16 PAHs. The sampling sites had higher proportions of high weight molecular ringed PAHs with higher proportions of benzo (a) pyren (BaP) and benzo (k) fluoranthene (BkF). The main source of PAHs was petroleum, coal/biomass combustion, and vehicular emission in these sampling sites. According to Canadian soil quality guidelines, 60% sites had a significant risk to human health. Moreover, 50% sites had high ecological risk and 30% sites were close to this critical value. Notably, PAH levels were significantly higher in VS than BS; moreover, VS had higher organic matter (OM) content, soil dehydrogenase (sDHA) activity, and lower pH and salt content. A structural equation model was established to explore the effects of soil properties on PAH concentration in VS. The result revealed that OM and sDHA were meaningful to enhance the adsorption and biological fixation of PAHs. This study will provide basic information on PAH level and potential application for phytoremediation.


Assuntos
Carvão Mineral/análise , Fluorenos/química , Campos de Petróleo e Gás/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Solo/química , Emissões de Veículos/análise , Canadá , China , Humanos , Hidrocarbonetos Policíclicos Aromáticos/química
20.
Zhonghua Yi Xue Za Zhi ; 88(24): 1711-4, 2008 Jun 24.
Artigo em Zh | MEDLINE | ID: mdl-19024545

RESUMO

OBJECTIVE: To investigate the neuroprotective effect of epigallocatechin gallate(EGCG), the main extract from green tea, on the oxidative-stress-injured retinal ganglion cells. METHODS: Rat retinal ganglion cells (RGC-5) were cultured into 3 groups (normal control; H2O2; H2O2 + EGCG or Trolox or NU1025). In-situ TUNEL was used to detect the apoptosis of the RGC-5 cells. Dihydroethidium (DHE) assay was used to observe the intracellular ROS generation. The activation of nuclear enzyme, PARP-1 was quantitatively detected by Western blot and the cell viability was measured by MT method. RESULTS: Hydrogen peroxide reduced RGC-5 cell viability in a time-concentration-dependent manner. The treatment of 500 micromol/L H2O2 for 24 hours reduced RGC-5 cell viability by about 50% of control. Hydrogen peraoxide caused apoptosis of the RGC-5 cell, obviously increased intracellular ROS generation and up-regulated the PARP-1 expression. The pretreatment with EGCG was able to markedly reduce the number of apoptotic cells, attenuate intracellular ROS generation. Furthermore, MTT assay showed that the pretreatment with EGCG (50 micromol/L) increased the most cell viability to 87% of control, but pretreatment with Trolox (100 micromol/L) and NU1025 (100 micromol/L, a PARP-1 inhibitor) recovered the most cell viability to 62% and 71% of control respectively. CONCLUSION: EGCG is able to effectively protect retinal ganglion cell against oxidative-stressed injury and can be used as a very potential neuroprotective drug.


Assuntos
Catequina/análogos & derivados , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Células Ganglionares da Retina/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Catequina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Peróxido de Hidrogênio/farmacologia , Marcação In Situ das Extremidades Cortadas , Ratos , Espécies Reativas de Oxigênio/metabolismo , Células Ganglionares da Retina/citologia , Células Ganglionares da Retina/metabolismo , Chá/química
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