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1.
J Hazard Mater ; 479: 135739, 2024 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-39243536

RESUMEN

Bioelectrochemical system (BES) is a promising technology for uranium recovery, which also enables simultaneous electricity generation. However, the bioelectrochemical recovery of uranium is hindered by its slow process due to the low reduction potential provided by microorganisms. Herein, we developed an innovative bioelectrochemical-photocatalytic system (BEPS) that combines the advantages of BES and photocatalysis, achieving enhanced uranium removal and recovery. The photogenerated electrons in BEPS possess a more negative reduction potential and stronger reduction capability than microbial electrons in BES, significantly accelerating uranium reduction and deposition on the electrode surface. Moreover, the electrons from the bioanode combine with photogenerated holes through the external circuit, effectively inhibiting the recombination of charge carriers. The BEPS significantly enhances uranium removal efficiency, kinetic, and electricity generation through a synergistic coupling mechanism between the bioanode and photocathode. Notably, the UO2 deposited on the electrode surface exhibited a recovery efficiency of 98.21 ± 1.37%, and the regenerated electrode sustained its photoelectric response and uranium removal capabilities. Our findings highlight the potential of the BEPS as an effective technology for uranium recovery and electricity generation.

2.
Front Oncol ; 14: 1385600, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39175479

RESUMEN

Background: With the widespread use of computed tomography (CT), the detection rate of pulmonary nodules in children has gradually increased. Due to the lack of epidemiological evidence and clinical guideline on pulmonary nodule treatment in children, we aimed to provide a reference for the clinical diagnosis and management of pediatirc pulmonary nodules. Methods: This retrospective study collected consecutive cases from April 2012 to July 2021 in the Shanghai Children's Medical Center. The sample included children with pulmonary nodules on chest CT scans and met the inclusion criteria. All patients were categorized into tumor and non-tumor groups by pre-CT clinical diagnosis. Nodule characteristics between groups were analyzed. To establish a clinical assessment model for the benign versus malignant pulmonary nodules, patients who have been followed-up for three months were detected and a decision tree model for nodule malignancy prediction was constructed and validated. Results: The sample comprised 1341 patients with an average age of 7.2 ± 4.6 years. More than half of them (51.7%) were diagnosed with malignancies before CT scan. 48.3% were diagnosed with non-tumor diseases or healthy. Compared to non-tumor group, children with tumor were more likely to have multiple nodules in both lungs, with larger size and often be accompanied by osteolytic or mass lesions. Based on the decision tree model, patients' history of malignancies, nodules diameter size≥5mm, and specific nodule distribution (multiple in both lungs, multiple in the right lung or solitary in the upper or middle right lobe) were important potential predictors for malignity. In the validation set, sensitivity, specificity and AUC were 0.855, 0.833 and 0.828 (95%CI: 0.712-0.909), respectively. Conclusion: This study conducted a clinical assessment model to differentiate benignity and malignancy of pediatric pulmonary nodules. We suggested that a nodule's diameter, distribution and patient's history of malignancies are predictable factors in benign or malignant determination.

3.
Mol Pharm ; 21(7): 3502-3512, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38861472

RESUMEN

Paclitaxel (PTX) is one of the first-line drugs for prostate cancer (PC) treatment. However, the poor water solubility, inadequate specific targeting ability, multidrug resistance, and severe neurotoxicity are far from being fully resolved, despite diverse PTX formulations in the market, such as the gold-standard PTX albumin nanoparticle (Abraxane) and polymer micelles (Genexol-PM). Some studies attempting to solve the multiple problems of chemotherapy delivery fall into the trap of an extremely complicated formulation design and sacrifice druggability. To better address these issues, this study designed an efficient, toxicity-reduced paclitaxel-ginsenoside polymeric micelle (RPM). With the aid of the inherent amphiphilic molecular structure and pharmacological effects of ginsenoside Rg5, the prepared RPM enhances the water solubility and active targeting of PTX, inhibiting chemotherapy resistance in cancer cells. Moreover, the polymeric micelles demonstrated favorable anti-inflammatory and neuroprotective effects, providing ideas for the development of new clinical anti-PC preparations.


Asunto(s)
Resistencia a Antineoplásicos , Ginsenósidos , Micelas , Paclitaxel , Ginsenósidos/química , Ginsenósidos/farmacología , Paclitaxel/farmacología , Paclitaxel/química , Humanos , Resistencia a Antineoplásicos/efectos de los fármacos , Animales , Masculino , Ratones , Línea Celular Tumoral , Neoplasias de la Próstata/tratamiento farmacológico , Portadores de Fármacos/química , Solubilidad , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química , Sistemas de Liberación de Medicamentos/métodos , Polímeros/química
4.
Bioresour Technol ; 406: 131046, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38936676

RESUMEN

Anaerobic ammonia oxidation (anammox) is a cost-effective technology but its performance can be seriously inhibited by high load stress. This study has created an innovative iron-rich encrustation layer (IEL) on the surface of anammox granules (AnGS) through the addition of a certain amount of nano zero-valent iron. The IEL was formed through the aggregation of a gel network and the binding of iron species with extracellular polymeric substances (EPS), resulting in a significant increase in settling ability, EPS secretion, and heme content. Metagenomic analysis indicated a notable rise in the functional genes associated with nitrogen andiron metabolism in IEL AnGS. Under high load stress, the ammonia removal performance of AnGS without IEL severely declined. In contrast, IEL AnGS exhibited excellent ammonia removal efficiency of over 90%. The IEL served as a protective barrier for AnGS, effectively mitigating the strong shear forces, thereby enhancing their resistance to high load stress.


Asunto(s)
Amoníaco , Hierro , Amoníaco/metabolismo , Hierro/química , Hierro/metabolismo , Oxidación-Reducción , Anaerobiosis , Reactores Biológicos , Matriz Extracelular de Sustancias Poliméricas/metabolismo
5.
Ultrason Sonochem ; 103: 106768, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38241945

RESUMEN

The blood-brain barrier (BBB) maintains brain homeostasis, regulates influx and efflux transport, and provides protection to the brain tissue. Ultrasound (US) and microbubble (MB)-mediated blood-brain barrier opening is an effective and safe technique for drug delivery in-vitro and in-vivo. However, the exact mechanism underlying this technique is still not fully elucidated. The aim of the study is to explore the contribution of transcytosis in the BBB transient opening using an in-vitro model of BBB. Utilizing a diverse set of techniques, including Ca2+ imaging, electron microscopy, and electrophysiological recordings, our results showed that the combined use of US and MBs triggers membrane deformation within the endothelial cell membrane, a phenomenon primarily observed in the US + MBs group. This deformation facilitates the vesicles transportation of 500 kDa fluorescent Dextran via dynamin-/caveolae-/clathrin- mediated transcytosis pathway. Simultaneously, we observed increase of cytosolic Ca2+ concentration, which is related with increased permeability of the 500 kDa fluorescent Dextran in-vitro. This was found to be associated with the Ca2+-protein kinase C (PKC) signaling pathway. The insights provided by the acoustically-mediated interaction between the microbubbles and the cells delineate potential mechanisms for macromolecular substance permeability.


Asunto(s)
Barrera Hematoencefálica , Dextranos , Barrera Hematoencefálica/metabolismo , Encéfalo/metabolismo , Acústica , Microburbujas , Colorantes , Sistemas de Liberación de Medicamentos/métodos , Comunicación Celular
6.
IEEE Trans Biomed Circuits Syst ; 16(5): 867-881, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36070274

RESUMEN

It has proved that the auscultation of respiratory sound has advantage in early respiratory diagnosis. Various methods have been raised to perform automatic respiratory sound analysis to reduce subjective diagnosis and physicians' workload. However, these methods highly rely on the quality of respiratory sound database. In this work, we have developed the first open-access paediatric respiratory sound database, SPRSound. The database consists of 2,683 records and 9,089 respiratory sound events from 292 participants. Accurate label is important to achieve a good prediction for adventitious respiratory sound classification problem. A custom-made sound label annotation software (SoundAnn) has been developed to perform sound editing, sound annotation, and quality assurance evaluation. A team of 11 experienced paediatric physicians is involved in the entire process to establish golden standard reference for the dataset. To verify the robustness and accuracy of the classification model, we have investigated the effects of different feature extraction methods and machine learning classifiers on the classification performance of our dataset. As such, we have achieved a score of 75.22%, 61.57%, 56.71%, and 37.84% for the four different classification challenges at the event level and record level.


Asunto(s)
Algoritmos , Ruidos Respiratorios , Humanos , Niño , Auscultación , Aprendizaje Automático , Bases de Datos Factuales
7.
Front Pediatr ; 10: 1043047, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36699301

RESUMEN

Objective: To follow up on the changes in pulmonary function phenotypes in children with asthma in the first year after diagnosis, and explore the risk factors of poor control in children with good treatment compliance. Methods: Children who were diagnosed with asthma in the Respiratory Department of Shanghai Children's Medical Center from January 1, 2019 to December 31, 2020 and were re-examined every 3 months after diagnosis for 1 year were continuously included, regardless of gender. We collected the clinical data, analyzed clinical characteristics of the different pulmonary function phenotypes at baseline and explored risk factors of poor asthma control after 1 year of standardized treatment. Results: A total of 142 children with asthma were included in this study, including 54 (38.0%) with normal pulmonary function phenotype (NPF), 75 (52.8%) with ventilation dysfunction phenotype (VD), and 13 (9.2%) with small airway dysfunction phenotype (SAD) in the baseline. Among them, there were statistically significant differences in all spirometry parameters, age, and course of disease before diagnosis (P < 0.05), and a negative correlation between age (r 2 = -0.33, P < 0.001), course of disease before diagnosis (r 2 = -0.23, P = 0.006) and FEV1/FVC. After 1-year follow-up, large airway function parameters and small airway function parameters were increased, fractional exhaled nitric oxide (FeNO) was decreased, the proportion of NPF was increased, the proportion of VD was decreased (P < 0.05), while there was no significant difference in the proportion of SAD. After 1 year of standardized treatment, 21 patients (14.8%) still had partly controlled or uncontrolled asthma. Our results showed that the more asthma attacks occurred within 1 year (OR = 6.249, 95% CI, 1.711-22.818, P = 0.006), the more times SAD presented at baseline and Assessment 1-4 (OR = 3.092, 95% CI, 1.222-7.825, P = 0.017), the higher the possibility of incomplete control of asthma. Conclusion: About 15% of the children with good treatment compliance were still not completely controlled after 1 year of treatment, which is closely associated with persistent small airway dysfunction.

8.
J Environ Sci (China) ; 110: 21-27, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34593191

RESUMEN

The redox state of arsenic controls its toxicity and mobility in the subsurface environment. Understanding the redox reactions of arsenic is particularly important for addressing its environmental behavior. Clay minerals are commonly found in soils and sediments, which are an important host for arsenic. However, limited information is known about the redox reactions between arsenic and structural Fe in clay minerals. In this study, the redox reactions between As(III)/As(V) and structural Fe in nontronite NAu-2 were investigated in anaerobic batch experiments. No oxidation of As(III) was observed by the native Fe(III)-NAu-2. Interestingly, anaerobic oxidation of As(III) to As(V) occurred after Fe(III)-NAu-2 was bioreduced. Furthermore, anaerobic oxidization of As(III) by bioreduced NAu-2 was significantly promoted by increasing Fe(III)-NAu-2 reduction extent and initial As(III) concentrations. Bioreduction of Fe(III)-NAu-2 generated reactive Fe(III)-O-Fe(II) moieties at clay mineral edge sites. Anaerobic oxidation of As(III) was attributed to the strong oxidation activity of the structural Fe(III) within the Fe(III)-O-Fe(II) moieties. Our results provide a potential explanation for the presence of As(V) in the anaerobic subsurface environment. Our findings also highlight that clay minerals can play an important role in controlling the redox state of arsenic in the natural environment.


Asunto(s)
Arsénico , Arsenitos , Anaerobiosis , Compuestos Férricos , Hierro , Minerales , Oxidación-Reducción
9.
J Environ Manage ; 288: 112333, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33823446

RESUMEN

Intensifying competition for water induces the growth of water markets in several countries for sharing water between rural communities and cities. While there is a growing recognition that adoption of market mechanisms in environmental governance relies on the state and different institutional arrangements, much less is known about how the interconnections among the state, market-tools, and the community work in practice. In China's distinctive political system, the central government has adopted a 'Two-Hands' approach () to water governance - a combination of strong central regulation and infrastructure development on the one hand, and adoption of market principles on the other to improve water reallocation. A recent study has explored the policy evolution underpinning this transition. However, no studies have systematically examined the implementation of the Two-Hands approach to reveal the underlying institutional hybrid patterns in environmental governance. This study fills this research gap by employing a Fuzzy Set Qualitative Comparative Analysis (fsQCA) to analyze how the interplay of the central government, market, and local governance shapes water rights trading patterns. A total of 29 water-scarce cities using water rights trading with 385 transactions were investigated for the period between 2000 and 2019 by combining evidence from fsQCA and qualitative case-studies. The implications drawn from interpreting the results are as follows: (1) the central government shapes the development of the market and its transactions but this is expressed in multiple ways through pilot projects and the national water exchange platform; (2) establishing water markets and investing in water infrastructure are mutually reinforcing, rather than mutually exclusive; and (3) local governments employ different property rights arrangements to adapt water markets in China's centralized politically institutional context.


Asunto(s)
Conservación de los Recursos Naturales , Política Ambiental , China , Ciudades , Agua
10.
Artículo en Inglés | MEDLINE | ID: mdl-33445697

RESUMEN

In the face of a public health crisis full of uncertainty, how should the community respond in order to effectively reduce the negative impact of the epidemic on public health? This article takes a Chinese rural community located near Wuhan City as an example to explore the mechanism of how collaborative leadership enhanced collective action in community governance against the COVID-19 pandemic. Early blockading to prevent transmission into the community, strict maintenance of social distance to prevent internal diffusion, timely elimination of public panic, and efficient guarantees of household supplies have proven effective in preventing the spread of the epidemic. Our research shows that collaborative leadership can achieve these goals mainly by effectively integrated local knowledge, modern information technology, and social self-organization, and then promoting the realization of collective action of community epidemic prevention and control. The lessons and implications for public health are discussed.


Asunto(s)
COVID-19 , Liderazgo , Política , Salud Pública , China , Humanos , Pandemias/prevención & control , Población Rural , SARS-CoV-2 , Incertidumbre
12.
IEEE Trans Biomed Eng ; 68(5): 1627-1637, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33001797

RESUMEN

OBJECTIVE: Arterial wall deformation, stiffness, and luminal pressure are well-recognized predictors of cardiovascular diseases but intertwined. Establishing a relationship among these three predictors is therefore important for comprehensive assessment of the circulatory system, but very few studies focused on this. METHODS: In this study, we first derived a mathematical description for localized luminal pressure change ( ∆p) as a function of arterial wall strains ( ε) and shear modulus ( µT) in the transverse plane; the arterial wall was modelled as a transversely isotropic and piecewise linearly-elastic material. Finite element simulations (FES) and in vitro fluid-driven inflation experiments were performed on arteries with both normal and abnormal geometries. ε and µT in the experimental study were estimated by an ultrasound elastographic imaging framework (UEIF). RESULTS: FES results showed good accuracy (percent errors ≤ 6.42%) of the proposed method for all simulated artery models. Experimental results showed good repeatability and reproducibility. Estimated ∆p pp values (average peak-to-peak pressure change) compared with pressure meter measurements in two normal geometry phantoms and an excised aorta were 65.95 ± 4.29 mmHg vs. 66.45 ± 3.80 mmHg, 60.49 ± 1.82 mmHg vs. 59.92 ± 2.69, and 36.03 ± 1.90 mmHg vs. 38.8 ± 3.21 mmHg, respectively. For the artery with abnormal geometry mimicking a simple plaque shape, the feasibility of the proposed method for ∆p estimation was also validated. CONCLUSION: Results demonstrated that UEIF with the proposed mathematical model, which lumped wall deformation, stiffness and luminal pressure, could estimate the localized dynamic luminal pressure change noninvasively and accurately.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Aorta , Arterias/diagnóstico por imagen , Fantasmas de Imagen , Reproducibilidad de los Resultados
13.
Sci Total Environ ; 763: 144613, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33383508

RESUMEN

Clay minerals are an important host for arsenic in many arsenic-affected areas. The role of bioreduction of structural Fe(III) in clay minerals in the mobilization of arsenic from clay minerals, however, still remains unclear. In this study, Fe(III) reducing bacterium, As(V) reducing bacterium, and Fe(III)-As(V) reducing bacterium were employed to investigate the possible bioreduction pathways for arsenic release from Nontronite NAu-2. Results demonstrated that microbial reduction controlled arsenic mobilization from NAu-2 through Fe(III), As(V), and simultaneous Fe(III)-As(V) reduction pathways. Although the bioreduction of structural Fe(III) led to a negligible dissolution of NAu-2, it triggered a significant release of arsenic from NAu-2. The bioreduction of tetrahedral Fe(III) initiated the release of As(V), and the further bioreduction of octahedral Fe(III) induced the release of As(III) in NAu-2. In addition, bioreduction of As(V) resulted in the desorption and transformation of As(V) from NAu-2. Simultaneous bioreduction of Fe(III) and As(V) led to an almost complete release of As(V) from NAu-2. These findings suggest that simultaneous Fe(III)-As(V) reduction was the dominant pathway governing As(V) release from NAu-2, while structural Fe(III) reduction controlled As(III) release from NAu-2. Therefore, the bioreduction of iron-bearing clay minerals has a great potential for arsenic mobilization in the subsurface environment.


Asunto(s)
Arsénico , Hierro , Arseniatos , Arcilla , Compuestos Férricos , Minerales , Oxidación-Reducción
14.
Int J Rheum Dis ; 23(10): 1288-1296, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32761870

RESUMEN

Psoriatic arthritis (PsA) is a common, chronic inflammatory disease with complex pathogenesis. In recent years, a number of susceptibility non-human leukocyte antigen (HLA) genes of PsA have been revealed, which also act as important factors in the pathogenesis of PsA as well as HLA genes. By searching the databases National Center for Biotechnology Information, Google and PubMed, 37 articles are included and 50 susceptibility non-HLA genes for PsA are presented, such as IL23A, TNIP1, TYK2, STAT4, IL12B, RUNX3 and TRAF3IP2. In these non-HLA genes, some are common genes shared with other diseases, whereas most of these susceptibility genes are related to the pathogenesis of PsA by activation or inhibition of the signaling pathways. Several signaling pathways possibly implicated in the pathogenesis of PsA are introduced in this paper, including the 2 mainly signaling pathways, IL23/Th17 signaling pathway and NF-κB signaling pathway, and the other involved signaling pathways, such as JAK-STAT signaling pathway and MAPK signaling pathway.


Asunto(s)
Inmunidad Adaptativa/genética , Artritis Psoriásica/genética , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo/métodos , Antígenos HLA/genética , Artritis Psoriásica/inmunología , Antígenos HLA/inmunología , Humanos , Transducción de Señal
15.
Ultrasound Med Biol ; 45(5): 1184-1196, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30876671

RESUMEN

Studies of non-destructive bidirectional ultrasound assessment of non-linear mechanical behavior of the artery are scarce in the literature. We hereby propose derivation of a strain-shear modulus relationship as a new graphical diagnostic index using an ultrasound elastographic imaging framework, which encompasses our in-house bidirectional vascular guided wave imaging (VGWI) and ultrasound strain imaging (USI). This framework is used to assess arterial non-linearity in two orthogonal (i.e., longitudinal and circumferential) directions in the absence of non-invasive pressure measurement. Bidirectional VGWI estimates longitudinal (µL) and transverse (µT) shear moduli, whereas USI estimates radial strain (ɛr). Vessel-mimicking phantoms (with and without longitudinal pre-stretch) and in vitro porcine aortas under static and/or dynamic physiologic intraluminal pressure loads were examined. ɛr was found to be a suitable alternative to intraluminal pressure for representation of cyclic loading on the artery wall. Results revealed that µT values of all samples examined increased non-linearly with εr magnitude and more drastically than µL, whereas µL values of only the pre-stretched phantoms and aortas increased with ɛr magnitude. As a new graphical representation of arterial non-linearity and function, strain-shear modulus loops derived by the proposed framework over two consecutive dynamic loading cycles differentiated sample pre-conditions and corroborated direction-dependent non-linear mechanical behaviors of the aorta with high estimation repeatability.


Asunto(s)
Aorta/diagnóstico por imagen , Aorta/fisiopatología , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/fisiopatología , Diagnóstico por Imagen de Elasticidad/métodos , Animales , Modelos Animales de Enfermedad , Módulo de Elasticidad/fisiología , Humanos , Fantasmas de Imagen , Resistencia al Corte/fisiología , Porcinos
16.
Ultrasound Med Biol ; 44(12): 2821-2837, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30241727

RESUMEN

Guided wave imaging for the artery remains in its infancy in clinical practice mainly because of complex arterial microstructure, hemodynamics and boundary conditions. Despite the theoretically known potential effect of the surrounding medium on guided wave propagation in thin media in non-destructive testing, experimental evidence pertaining to thin soft materials, such as the artery, is relatively scarce in the relevant literature. Therefore, this study first evaluated the propagating guided wave generated by acoustic radiation force in polyvinyl alcohol-based hydrogel plates differing in thickness and stiffness under various material coupling conditions (water and polyvinyl alcohol bulk). A thin-walled polyvinyl alcohol hollow cylindrical phantom coupled by softer gelatin-agar phantoms and an excised porcine aorta surrounded by water and pork belly were further examined. Guided waves in the thin structure and shear waves in the bulk media were captured by ultrafast ultrasound imaging, and guided wave dispersion as a function of the frequency-thickness product was analyzed using the zero-order anti-symmetric Lamb wave model to estimate the shear modulus of each thin medium studied. Results confirmed the deviated shear modulus estimates from the ground truth for thin plates, the thin-walled hollow cylindrical phantom and the porcine aorta bounded by stiffness-unmatched bulk medium. The findings indicated the need for (i) careful interpretation of estimated shear moduli of thin structure bounded by bulk media and (ii) a generalized guided wave model that takes into account the effect of coupling medium.


Asunto(s)
Aorta/diagnóstico por imagen , Diagnóstico por Imagen de Elasticidad/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Fantasmas de Imagen , Algoritmos , Animales , Hidrogel de Polietilenoglicol-Dimetacrilato , Modelos Animales , Modelos Biológicos , Polivinilos , Porcinos
17.
Zhongguo Zhong Yao Za Zhi ; 43(13): 2690-2696, 2018 Jul.
Artículo en Chino | MEDLINE | ID: mdl-30111018

RESUMEN

Hispidulin(HPDL) chitosan microspheres were prepared in this study to deliver HPDL to the lesion sitevia intravenous injection, and further evaluate their anticancer effects in vitro and the growth inhibition effect on A549 cells spheroids. HPDL chitosan microspheres were prepared by emulsion crosslinking method with chitosan as a drug carrier and the amount of HPDL was determined by high performance liquid chromatography (HPLC). The morphology of microspheres was observed under laser scanning confocal microscope. Additionally, the drug release amount of targeting microspheres was detected by dialysis method. Furthermore, the anti-proliferative effects against A549 lung cancer cells were tested by sulforhodamine B (SRB) method, and the effects of HPDL chitosan micrpsphereson early apoptosis of A549 cellswere determined by flow cytometry. A549 cells tumor spheroids were developed in vitro and then HPDL chitosan microspheres were added. On the 0, 1, 3, 7 d after adding the drugs, the inverted microscope was used to observe the mythologicaland volume changes of A549 cells spheroids. The encapsulation efficiency of HPDL chitosan microspheres was (75.32±0.52)%, and the drug loading amount was (7.76±0.67)%. Meanwhile, the microspheres were round shaped andhad smooth surface. The HPDL chitosan microspheres exhibited stronger inhibitory effects on A549 lung cancer cells. The results of flow cytometry indicated that, the early apoptosis rate of lung cancer A549 cells was (37.0±0.75)% at 24 h cells culture after drug administration. The volume of tumor spheroid was significantly inhibited, which had been shrunk by (50.09±11.06)% after the treatment by drug-loaded microsphere at day 7 as compared with blank group; meanwhile, the cells surface were obviously lysed. The preparation method in this research was simple and practicable, and the microspheres prepared with this method were round and smooth, with high encapsulation efficiency, which can significantly inhibit proliferation of lung adenocarcinoma A549 cells and induce cell apoptosis, and at the same time can cause lysisand death of A549 cell tumor spheroid.


Asunto(s)
Microesferas , Quitosano , Portadores de Fármacos , Flavonas
18.
Sci Total Environ ; 640-641: 591-598, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29870936

RESUMEN

Bioreduction of hexavalent chromium (Cr(VI)) to sparingly soluble trivalent chromium (Cr(III)) is a strategy for the remediation of Cr(VI) contaminated sites. However, its application is limited due to the slow bioreduction process. Here we explored the potential synergistic enhancement of iron(III) minerals (nontronite NAu-2, ferrihydrite, and goethite) and electron shuttle anthraquinone-2,6-disulfonate (AQDS) on the bioreduction of Cr(VI) by Shewanella oneidensis MR-1. AQDS alone increased the bioreduction rate of Cr(VI) by accelerating electron transfer from MR-1 to Cr(VI). Iron minerals alone did not increase the bioreduction rate of Cr(VI), where the electron transfer from MR-1 to Fe(III) minerals was inhibited due to the toxicity of Cr(VI) to MR-1. AQDS plus NAu-2 or ferrihydrite significantly enhanced the bioreduction rate of Cr(VI) as compared to AQDS or NAu-2/ferrihydrite alone, demonstrating that AQDS plus NAu-2/ferrihydrite had the synergistic effect on bioreduction of Cr(VI). Synergy factor (kcells+Fe+AQDS/(kcells+Fe + kcells+AQDS)) was used to quantify the synergistic effect of AQDS and iron minerals on the bioreduction of Cr(VI). The synergy factors of AQDS plus NAu-2 were 2.09-4.63 (three Cr(VI) spikes), and the synergy factors of AQDS plus ferrihydrite were 1.89-4.61 (two Cr(VI) spikes). In the presence of Cr(VI), AQDS served as the electron shuttle between MR-1 and iron minerals, facilitating the reduction of Fe(III) minerals to Fe(II). The synergistic enhancement of AQDS and NAu-2/ferrihydrite was attributed to the generated Fe(II), which could quickly reduce Cr(VI) to Cr(III). Our results provide an attractive strategy to strengthen the bio-immobilization of Cr(VI) at iron-rich contaminated sites through the synergistic enhancement of iron(III) minerals and electron shuttle.


Asunto(s)
Antraquinonas/química , Cromo/química , Hierro/química , Shewanella/fisiología , Antraquinonas/metabolismo , Cromo/metabolismo , Compuestos Férricos/química , Minerales , Oxidación-Reducción
19.
Ultrasound Med Biol ; 44(4): 884-896, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29402485

RESUMEN

We previously found that vascular guided wave imaging (VGWI) could non-invasively quantify transmural wall stiffness in both the longitudinal (r-z plane, 0°) and circumferential (r-θ plane, 90°) directions of soft hollow cylinders. Arterial stiffness estimation in multiple directions warrants further comprehensive characterization of arterial health, especially in the presence of asymmetric plaques, but is currently lacking. This study therefore investigated the multidirectional estimation of the arterial Young's modulus in a finite-element model, in vitro artery-mimicking phantoms and an excised porcine aorta. A longitudinal pre-stretch of 20% and/or lumen pressure (15 or 70 mm Hg) was additionally introduced to pre-condition the phantoms for emulating the intrinsic mechanical anisotropy of the real artery. The guided wave propagation was approximated by a zero-order antisymmetric Lamb wave model. Shape factor, which was defined as the ratio of inner radius to thickness, was calculated over the entire segment of each planar cross section of the hollow cylindrical structure at a full rotation (0°-360° at 10° increments) about the radial axis. The view-dependent geometry of the cross segment was found to affect the guided wave propagation, causing Young's modulus overestimation in four angular intervals along the propagation pathway, all of which corresponded to wall regions with low shape factors (<1.5). As validated by mechanical tensile testing, the results indicate not only that excluding the propagation pathway with low shape factors could correct the overestimation of Young's modulus, but also that VGWI could portray the anisotropy of hollow cylindrical structures and the porcine aorta based on the derived fractional anisotropy values from multidirectional modulus estimates. This study may serve as an important step toward 3-D assessment of the mechanical properties of the artery.


Asunto(s)
Diagnóstico por Imagen de Elasticidad/métodos , Interpretación de Imagen Asistida por Computador/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Fantasmas de Imagen , Rigidez Vascular , Animales , Modelos Animales , Porcinos
20.
Oncotarget ; 8(38): 64129-64142, 2017 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-28969057

RESUMEN

Brain gliomas, one of the most fatal tumors to human, severely threat the health and life of human. They are capable of extremely strong invasion ability. And invasive glioma cells could rapidly penetrate into normal brain tissues and break them. We prepared a kind of functional liposomes, which could be transported acrossing the blood-brain barrier (BBB) and afterwards induce the apoptosis of glioma stem cells. In this research, we chose ursolic acids (UA) as an anti-cancer drug to inhibit the growth of C6 glioma cells, while epigallocatechin 3-gallate(EGCG) as the agent that could induce the apoptosis of C6 glioma stem cells. With the targeting ability of MAN, the liposomes could be delivered through the BBB and finally were concentrated on the brain gliomas. Cell experiments in vitro demonstrated that the functional liposomes were able to significantly enhance the anti-cancer effects of the drugs due to promoting the apoptosis and endocytosis effects of C6 glioma cells and C6 glioma stem cells at the same time. Furthermore, the evaluations through animal models showed that the drugs could obviously prolong the survival period of brain glioma-bearing mice and inhibit the tumor growth. Consequently, multifunctional targeting ursolic acids liposomes could potentially improve the therapeutic effects on C6 glioma cells and C6 glioma stem cells.

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