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1.
J Pharm Biomed Anal ; 248: 116326, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38959756

RESUMO

Antibiotic-associated diarrhea (AAD) is a common side effect of antibiotic therapy, characterized by intestinal inflammation which reduces the quality of life of patients. Xianglian Pill (XLP) has long been used to treat abdominal pain, diarrhea, bacillary dysentery and enteritis. Studies found that XLP has curative effect on AAD; however, the chemical constituents and mechanism of XLP have not been fully elucidated because of the lack of in vitro and in vivo studies. In this study, ultra-high performance liquid chromatography mass spectrometry method (UPLC-Q-Exactive-Orbitrap-HRMS) was used to examine the components of the XLP. Then, the binding between active compounds and the key targets was studied using network pharmacology and molecular docking. A comparative tissue distribution study was established for the simultaneous determination of the 10 active components in healthy and AAD mouse models. Forty-six components were characterized from XLP. According to the network pharmacology degree value, a prediction was made that encompassed 42 components and 14 core targets, which were intricately involved in crucial biological pathways, such as the AGE-RAGE signaling, cellular senescence, and MAPK signaling. Tissue distribution analysis showed that the 10 components were widely distributed in the heart, liver, spleen, lungs, kidneys, small intestine, and large intestine of mice, with varying concentrations in healthy and AAD mice. Molecular docking analysis also indicated that the active compounds in the tissue distribution could bind tightly to key targets of network pharmacological studies. This study provides a reference for further investigations of the relationships between the chemical components and pharmacological activities of XLP.

2.
Foods ; 13(13)2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38998640

RESUMO

The Russia-Ukraine conflict is a growing concern worldwide and poses serious threats to regional and global food security. Using monthly trade data for maize, rice, and wheat from 2016/1 to 2023/12, this paper constructs three international crop trade networks and an aggregate international food trade network. We aim to examine the structural changes following the occurrence of the Russia-Ukraine conflict. We find significant shifts in the number of edges, average in-degree, density, and efficiency in the third quarter of 2022, particularly in the international wheat trade network. Additionally, we have shown that political reasons have caused more pronounced changes in the trade connections between the economies of the North Atlantic Treaty Organization and Russia than with Ukraine. This paper could provide insights into the negative impact of geopolitical conflicts on the global food system and encourage a series of effective strategies to mitigate the negative impact of the conflict on global food trade.

3.
ACS Nano ; 18(19): 12453-12467, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38686995

RESUMO

Traditional magnetic resonance imaging (MRI) contrast agents (CAs) are a type of "always on" system that accelerates proton relaxation regardless of their enrichment region. This "always on" feature leads to a decrease in signal differences between lesions and normal tissues, hampering their applications in accurate and early diagnosis. Herein, we report a strategy to fabricate glutathione (GSH)-responsive one-dimensional (1-D) manganese oxide nanoparticles (MONPs) with improved T2 relaxivities and achieve effective T2/T1 switchable MRI imaging of tumors. Compared to traditional contrast agents with high saturation magnetization to enhance T2 relaxivities, 1-D MONPs with weak Ms effectively increase the inhomogeneity of the local magnetic field and exhibit obvious T2 contrast. The inhomogeneity of the local magnetic field of 1-D MONPs is highly dependent on their number of primary particles and surface roughness according to Landau-Lifshitz-Gilbert simulations and thus eventually determines their T2 relaxivities. Furthermore, the GSH responsiveness ensures 1-D MONPs with sensitive switching from the T2 to T1 mode in vitro and subcutaneous tumors to clearly delineate the boundary of glioma and metastasis margins, achieving precise histopathological-level MRI. This study provides a strategy to improve T2 relaxivity of magnetic nanoparticles and construct switchable MRI CAs, offering high tumor-to-normal tissue contrast signal for early and accurate diagnosis.


Assuntos
Meios de Contraste , Imageamento por Ressonância Magnética , Compostos de Manganês , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Animais , Camundongos , Meios de Contraste/química , Humanos , Campos Magnéticos , Glutationa/química , Óxidos/química , Linhagem Celular Tumoral , Glioma/diagnóstico por imagem , Glioma/patologia , Tamanho da Partícula , Nanopartículas de Magnetita/química
4.
Phys Rev E ; 109(1-1): 014126, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38366487

RESUMO

The temporal rich club (TRC) phenomenon is widespread in real systems, forming a tight and continuous collection of the prominent nodes that control the system. However, there is still a lack of sufficient understanding of the mechanisms of TRC formation. Here we use the international N-nutrient trade network as an example of an in-depth identification, analysis, and modeling of its TRC phenomenon. The system exhibits a statistically significant TRC phenomenon, with eight economies forming the cornerstone club. Our analysis reveals that node degree is the most influential factor in TRC formation compared to other variables. The mathematical evolution models we constructed propose that the TRC in the N-nutrient trade network arises from the coexistence of degree-homophily and path-dependence mechanisms. By comprehending these mechanisms, we introduce a different perspective on TRC formation. Although our analysis is limited to the international trade system, the methodology can be extended to analyze the mechanisms underlying TRC emergence in other systems.

5.
Environ Pollut ; 331(Pt 2): 121857, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37245791

RESUMO

Liver injury may cause many diseases, such as non-alcoholic fatty liver disease (NAFLD). Acetochlor is one of the representative chloroacetamide herbicides, and its metabolite 2-chloro-N-(2-ethyl-6-methyl phenyl) acetamide (CMEPA) is the main form of exposure in the environment. It has been shown that acetochlor can cause mitochondrial damage of HepG2 cells and induce apoptosis by activating Bcl/Bax pathway (Wang et al., 2021). But there has been less research on CMEPA. we explored the possibility of CMEPA and liver injury through biological experiments. In vivo, CMEPA (0-16 mg/L) induced liver damage in zebrafish larvae, including increased lipid droplets, changes in liver morphology (>1.3-fold) and increased TC/TG content (>2.5-fold). In vitro, we selected L02 (human normal liver cells) as the model, and explored its molecular mechanism. We found that CMEPA (0-160 mg/L) induced apoptosis (similar to 40%), mitochondrial damage and oxidative stress in L02 cells. CMEPA induced intracellular lipid accumulation by inhibiting AMPK/ACC/CPT-1A signaling pathway and activating SREBP-1c/FAS signaling pathway. Our study provides evidence of a link between CMEPA and liver injury. This raises concerns regarding the health risks of pesticide metabolites to liver health.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Animais , Humanos , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Peixe-Zebra , Fígado/metabolismo , Lipídeos , Metabolismo dos Lipídeos
6.
Heliyon ; 9(4): e14794, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37095958

RESUMO

Objective: In recent years, the introduction of immune checkpoint inhibitors (ICIs) has revolutionized the treatment of extensive-stage small cell lung carcinoma (ES-SCLC), but the optimal combination of ICI and standard chemotherapy strategy is yet to be established. The aim of this network meta-analysis (NMA) was to identify which first-line combination strategy is optimal for patients with ES-SCLC. Methods: PubMed, Embase, Cochrane Library, and the proceedings of international conferences, including American Society of Clinical Oncology and European Society for Medical Oncology meetings, were searched for randomized controlled trials (RCTs) published through October 31, 2022. The collected primary outcomes were overall survival (OS), progression-free survival (PFS), and grade 3-5 treatment-related adverse events (TRAEs). Results: Our NMA study included six phase 3 and three phase 2 RCTs including 4037 patients and 10 first-line regimens. Regarding effectiveness, the addition of programmed cell death 1 (PD-1) or programmed cell death ligand 1 (PD-L1) inhibitors to standard chemotherapy provided greater efficacy than chemotherapy alone. However, cytotoxic T lymphocyte-associated antigen-4 inhibitors were not associated with satisfactory prognoses. Serplulimab plus carboplatin-etoposide (vs. standard chemotherapy, hazard ratio [HR] = 0.63; 95% CI = 0.49-0.82) and nivolumab plus platinum-etoposide (HR = 0.65; 95% confidence interval [CI] = 0.46-0.91) displayed the greatest benefit regarding OS. In terms of PFS, serplulimab plus carboplatin-etoposide yielded the best benefit of all treatments (HR = 0.48; 95% CI = 0.39-0.6). The combination of ICIs and chemotherapy caused more toxicity in general, but durvalumab plus platinum-etoposide (odds ratio [OR] = 0.98; 95% CI = 0.68-1.4), atezolizumab plus carboplatin-etoposide (OR = 1.04; 95% CI = 0.68-1.6), and adebrelimab plus platinum-etoposide (OR = 1.02; 95% CI = 0.52-2) displayed similar safety as standard chemotherapy. Subgroup analysis by race illustrated that serplulimab plus carboplatin-etoposide was associated with the best OS in Asian patients. And in non-Asian patients, the combination of PD-1/PD-L1 inhibitors and chemotherapy (pembrolizumab plus platinum-etoposide, durvalumab plus platinum-etoposide, and durvalumab and tremelimumab plus platinum-etoposide) displayed superiority to standard chemotherapy. Conclusions: The results of our NMA study suggested that serplulimab plus carboplatin-etoposide and nivolumab plus platinum-etoposide are associated with the best OS as first-line treatments for patients with ES-SCLC. Serplulimab plus carboplatin-etoposide was associated with the best PFS. In Asian patients, serplulimab plus carboplatin-etoposide had the best OS. Systematic review registration: This study is registered with PROSPERO, number CRD42022345850.

7.
Adv Healthc Mater ; 12(5): e2202043, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36367363

RESUMO

Photosensitizer in photodynamic therapy (PDT)  accumulates in both tumor and adjacent normal tissue due to low selective biodistribution, results in undesirable side effect with limited clinic application. Herein, an intelligent nanoplatform is reported that selectively acts as reactive oxygen species (ROS) scavenger in normal tissue but as ROS generator in tumor microenvironment (TME) to differentially control ROS level in tumor and surrounding normal tissue during PDT. By down-regulating the produced ROS with dampened cytokine wave in normal tissue after PDT, the nanoplatform reduces the inflammatory response of normal tissue in PDT, minimizing the side effect and tumor metastasis in PDT. Alternatively, the nanoplatform switches from ROS scavenger to generator through the glutathione (GSH) responsive degradation in TME, which effectively improves the PDT efficacy with reduced GSH level and amplified oxidative stress in tumor. Simultaneously, the released Mn ions provide real-time and in situ signal change of magnetic resonance imaging (MRI) to monitor the reversal process of catalysis activity and achieve accurate tumor diagnosis. This TME-responsive ROS scavenger/generator with activable MRI contrast may provide a new dimension for design of next-generation PDT agents with precise diagnosis, high therapeutic efficacy, and low side effect.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio , Distribuição Tecidual , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Imageamento por Ressonância Magnética , Linhagem Celular Tumoral , Nanopartículas/uso terapêutico , Microambiente Tumoral
8.
Front Psychol ; 14: 1264207, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38264422

RESUMO

What is the impact of environmental management system certification on green innovation performance, and is it a futile endeavor or a profitable one? Grounded in the principles of ecological civilization construction and green development, this study embarks on a comprehensive examination. Initially, it investigates the varying impacts of environmental management system certification on both traditional innovation performance and green innovation performance. Subsequently, it dissects the underlying mechanisms and moderating factors influencing the latter, including an exploration of intermediary effects. The empirical findings of this study are as follows: (i) Environmental management system certification emerges as a catalyst for innovation performance, with the primary impact observed in the realm of green innovation performance. (ii) Social responsibility disclosure is identified as a mediating factor in the relationship between environmental management system certification and green innovation performance. (iii) Larger enterprises, those equipped with robust equity incentives, and those operating in less competitive markets are more prone to benefit from the impact of environmental management system certification on social responsibility disclosure. This, in turn, amplifies the promotion of green innovation performance. However, the moderating effect of property rights on the mediating path remains statistically insignificant. (iv) Environmental management system certification exerts a more pronounced influence on green innovation performance in regions characterized by lower economic development. Moreover, it particularly stimulates exploratory green innovation performance, surpassing its impact on exploitative green innovation performance.

9.
J Colloid Interface Sci ; 626: 364-373, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35797871

RESUMO

Doping Mn (II) ions into iron oxide (IO) as manganese ferrite (MnIO) has been proved to be an effective strategy to improve T1 relaxivity of IO nanoparticle in recent years; however, the high T2 relaxivity of MnIO nanoparticle hampers its T1 contrast efficiency and remains a hurdle when developing contrast agent for early and accurate diagnosis. Herein, we engineered the interfacial structure of IO nanoparticle coated with manganese ferrite shell (IO@MnIO) with tunable thicknesses. The Mn-doped shell significantly improve the T1 contrast of IO nanoparticle, especially with the thickness of ∼0.8 nm. Compared to pristine IO nanoparticle, IO@MnIO nanoparticle with thickness of ∼0.8 nm exhibits nearly 2 times higher T1 relaxivity of 9.1 mM-1s-1 at 3 T magnetic field. Moreover, exclusive engineering the interfacial structure significantly lower the T2 enhancing effect caused by doped Mn (II) ions, which further limits the impairing of increased T2 relaxivity to T1 contrast imaging. IO@MnIO nanoparticles with different shell thicknesses reveal comparable T1 relaxation rates but obvious lower T2 relaxivities and r2/r1 ratios to MnIO nanoparticles with similar sizes. The desirable T1 contrast endows IO@MnIO nanoparticle to provide sufficient signal difference between normal and tumor tissue in vivo. This work provides a detailed instance of interfacial engineering to improve IO-based T1 contrast and a new guidance for designing effective high-performance T1 contrast agent for early cancer diagnosis.


Assuntos
Meios de Contraste , Nanopartículas , Meios de Contraste/química , Compostos Férricos , Nanopartículas Magnéticas de Óxido de Ferro , Imageamento por Ressonância Magnética/métodos , Compostos de Manganês/química , Nanopartículas/química
10.
Bioact Mater ; 12: 214-245, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35310380

RESUMO

Iron oxide nanoparticle (IONP) with unique magnetic property and high biocompatibility have been widely used as magnetic resonance imaging (MRI) contrast agent (CA) for long time. However, a review which comprehensively summarizes the recent development of IONP as traditional T 2 CA and its new application for different modality of MRI, such as T 1 imaging, simultaneous T 2/T 1 or MRI/other imaging modality, and as environment responsive CA is rare. This review starts with an investigation of direction on the development of high-performance MRI CA in both T 2 and T 1 modal based on quantum mechanical outer sphere and Solomon-Bloembergen-Morgan (SBM) theory. Recent rational attempts to increase the MRI contrast of IONP by adjusting the key parameters, including magnetization, size, effective radius, inhomogeneity of surrounding generated magnetic field, crystal phase, coordination number of water, electronic relaxation time, and surface modification are summarized. Besides the strategies to improve r 2 or r 1 values, strategies to increase the in vivo contrast efficiency of IONP have been reviewed from three different aspects, those are introducing second imaging modality to increase the imaging accuracy, endowing IONP with environment response capacity to elevate the signal difference between lesion and normal tissue, and optimizing the interface structure to improve the accumulation amount of IONP in lesion. This detailed review provides a deep understanding of recent researches on the development of high-performance IONP based MRI CAs. It is hoped to trigger deep thinking for design of next generation MRI CAs for early and accurate diagnosis.

11.
Chem Commun (Camb) ; 58(3): 399-402, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34908049

RESUMO

A palladium-catalyzed stereoselective synthesis of alkenyl boronates from N-methyliminodiacetyl boronate (BMIDA)-substituted N-tosylhydrazone and benzyl bromides is developed. A range of trans-alkenyl MIDA boronates as single stereoisomers were obtained in moderate yields with good functional group compatibility. The resultant boronate products may be transformed to other boron-containing compounds and may also be directly used in cross-coupling reactions.

12.
Artigo em Inglês | MEDLINE | ID: mdl-32570750

RESUMO

Environmental regulations (ERs) that can stimulate technological innovation (TI) are the key to enabling a win-win strategy that benefits both economic development and environmental protection. This study seeks to analyze the impacts of ERs on TI. Previous literature highlighted that the black box of TI can be decomposed into technology investment and technology transformation, but empirical studies on such a decomposition have largely been ignored. Moreover, a detailed discussion of the links between ERs and the decomposed components of TI has not been conducted in developing countries such as China. Our study attempts to address these research gaps by (i) decomposing TI using a novel data envelopment analysis (DEA) procedure and further analyzing the impacts of ERs on the decomposed components of TI and (ii) applying this novel methodology to Chinese context. Accordingly, this study is conducted in two stages. First, a novel application of the slack-based measure Network DEA model is developed to uncover the black box of TI using Chinese data in order to estimate the overall efficiency of technological innovation (TIE) and to decompose it into the efficiency of technology investment (TVE) and the efficiency of technology transformation (TTE). Second, a random effect Tobit model is applied to (i) investigate both the linear and nonlinear impacts of ERs on TIE in all sectors and (ii) examine whether the impacts of ERs on TVE and TTE in different subprocesses are heterogeneous or not. Our results have showed the benefits of decomposing TI: while technology transformation in China closely follows the trend of TI, the trend of technology investment is somewhat different. The estimation results further indicate that the impacts of ERs on TIE are nonlinear. Besides, ERs have heterogeneous impacts on the decomposed components of TI. The impacts of ERs on TVE are nonlinear, whereas the impacts of ERs on TTE are statistically insignificant.


Assuntos
Conservação dos Recursos Naturais , Desenvolvimento Econômico , Invenções , China , Regulamentação Governamental , Investimentos em Saúde
13.
Front Immunol ; 10: 1803, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31447838

RESUMO

Cytokine-amplified functional CD8+ T cells ensure effective eradication of tumors. Interleukin 36α (IL-36α), IL-36ß, and IL-36γ share the same receptor complex, composed of the IL-36 receptor (IL-36R), and IL-1RAcP. Recently, we revealed that IL-36γ greatly promoted CD8+ T cell activation, contributing to antitumor immune responses. However, the underlying mechanism of IL-36-mediated CD8+ T cell activation remains understood. In the current study, we proved that IL-36ß had the same effect on CD8+ T cell as IL-36γ, and uncovered that IL-36ß significantly activated mammalian target of rapamycin complex 1 (mTORC1) of CD8+ T cells. When mTORC1 was inhibited by rapamycin, IL-36ß-stimulated CD8+ T cell activation and expansion was drastically downregulated. Further, we elucidated that IL-36ß-mediated mTORC1 activation was dependent on the pathway of phosphatidylinositol 3 kinase (PI3K)/Akt, IκB kinase (IKK) and myeloid differentiation factor 88 (MyD88). Inhibition of PI3K or IKK by inhibitor, or deficiency of MyD88, respectively, suppressed mTORC1 signal, causing arrest of CD8+ T cell activation. Additionally, it was validated that IL-36ß significantly promoted mTORC1 activation and antitumor function of CD8+ tumor-infiltrating lymphocytes (TILs) in vivo, resulting in inhibition of tumor growth and prolongation of survival of tumor-bearing mice. Taken together, we substantiated that IL-36ß could promote CD8+ T cell activation through activating mTORC1 dependent on PI3K/Akt, IKK and MyD88 pathways, leading to enhancement of antitumor immune responses, which laid the foundations for applying IL-36ß into tumor immunotherapy.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Interleucina-1/imunologia , Ativação Linfocitária/imunologia , Alvo Mecanístico do Complexo 1 de Rapamicina/imunologia , Melanoma Experimental/imunologia , Animais , Linfócitos do Interstício Tumoral/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/imunologia , Neoplasias Cutâneas/imunologia , Microambiente Tumoral/imunologia
14.
Conserv Physiol ; 7(1): coz031, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31249688

RESUMO

The value of biological samples collected in the field is compromised if storage conditions result in analyte degradation, especially in warmer climates like Thailand. We evaluated the effects of time and temperature on immunoactive steroid hormone stability in Asian elephant (Elephas maximus) blood stored with and without an anti-coagulant before centrifugation. For each elephant (5 male, 5 female), whole blood was aliquoted (n = 2 ml each) into 13 red top (without anticoagulant) or purple top (with anticoagulant) tubes. One tube from each treatment was centrifuged immediately and the serum or plasma frozen at -20°C (Time 0, T0). The remaining 12 aliquots were divided into stored temperature groups: 4°C, room temperature (RT, ~22°C), and 37°C, and centrifuged after 6, 24, 48 and 62 h of storage. Serum and plasma concentrations of progestagens in females, testosterone in males and cortisol in both sexes were quantified by validated enzyme immunoassays. Steroid concentration differences from T0 were determined by a randomized complete block ANOVA and Dunnett's tests. The only evidence of hormone degradation was cortisol and testosterone concentrations in serum stored at 37°C. Testosterone concentrations declined by 34% at 48 h and 52% at 62 h, cortisol was decreased by 19% after 48 h and 27% after 62 h at 37°C, respectively. None of the other aliquots displayed significant changes over time at any temperature. In conclusion, steroids appear to be stable in blood for nearly 3 days at room or refrigeration temperatures before centrifugation; steroids in samples with ethylenediaminetetraacetic acid were particularly stable. However, warmer temperatures may negatively affect steroids stored without anti-coagulant, perhaps due to red blood cell metabolism. Thus, under field conditions with no access to cold or freezer temperatures, collection of plasma is a better choice for elephants up to at least 62 h before centrifugation.

15.
Org Biomol Chem ; 15(22): 4731-4749, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28540374

RESUMO

N-Heterocyclic carbenes (NHCs) have emerged as powerful and elegant organocatalysts in a variety of newly developed and unprecedented enantioselective transformations due to their unique umpolung capacity. As a supplement to conventional enantioselective organocatalysis, NHC-induced non-asymmetric catalysis has gradually attracted much interest in recent years. Herein, this review aims to reveal the recent developments in NHC-promoted non-asymmetric umpolung transformations resulting in the expeditious construction of versatile achiral natural heterocycles, carbocycles and acylated products.

17.
Org Biomol Chem ; 15(6): 1329-1333, 2017 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-28106218

RESUMO

A convergent and efficient NHC-catalyzed enantioselective tandem Michael addition/lactonization sequence of ynals with 1,2-dione as the dual-nucleophile is disclosed. This straightforward strategy expeditiously assembles the synthetically and pharmaceutically valuable optically active fused dihydropyranones in good to high yields (70-88%) and with excellent enantioselectivities (92-99% ee).

18.
Air Qual Atmos Health ; 7(1): 59-70, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29430261

RESUMO

Diesel engine emissions are an important source of ultrafine particulate matter (PM) in both ambient air and many occupational settings. Biodiesel is a popular, 'green' alternative to petroleum diesel fuel, but little is known about the impact of 'real world' biodiesel combustion on workplace PM concentrations and particle characteristics including size, morphology, and composition; or on biological responses. The objectives of the present work were to characterize PM workplace concentrations and tailpipe emissions produced by the combustion of commercially purchased low sulfur petrodiesel and a waste grease B20 blend (20% biodiesel/80% petrodiesel by volume) in heavy duty diesel (HDD) nonroad equipment operating in a 'real world' rural recycling center. Furthermore, we assessed the in vitro responses of cell lines representing human lung epithelial cells (BEAS-2B) and macrophages (THP-1) after 24 h of exposure to these real-world particles. Compared to petroleum diesel, use of B20 in HDD equipment resulted in lower mass concentrations of PM2.5, PM<0.25 (particle diameter less than 2.5 and 0.25 micrometer, respectively), and elemental carbon. Transmission electron analysis of PM showed that primary particle size and morphology were similar between fuel types. Metals composition analysis revealed differences between fuels, with higher Fe, Al, V, and Se measured during B20 use, and higher As, Cd, Cu, Mn, Ni and Pb concentrations measured during petrodiesel use. In vitro responses varied between fuels but data supported that waste grease B20 particles elicited inflammatory responses in human macrophages and lung epithelial cells comparable to petrodiesel particles. However, the effects were more pronounced with B20 than petrodiesel at the same mass concentration. Since the primary particle size and morphology were similar between fuels, it is likely that the differential results seen in the in vitro assays points to differences in the composition of the PM. Future research should focus on the organic carbon and metals speciation and potential impact of real world particles on reactive oxygen species generation and mechanisms for differences in the cellular inflammatory responses.

19.
Environ Sci Technol ; 47(21): 12496-504, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24053625

RESUMO

Debate about the biological effects of biodiesel exhaust emissions exists due to variation in methods of exhaust generation and biological models used to assess responses. Because studies in cells do not necessarily reflect the integrated response of a whole animal, experiments were conducted in two human cell lines representing bronchial epithelial cells and macrophages and female mice using identical particle suspensions of raw exhaust generated by a Volkswagen light-duty diesel engine using petrodiesel (B0) and a biodiesel blend (B20: 20% soy biodiesel/80% B0 by volume). Tailpipe particle emissions measurement showed B0 generated two times more particle mass, larger ultrafine particle number distribution modes, and particles of more nonpolar organic composition than the B20 fuel. Biological assays (inflammatory mediators, oxidative stress biomarkers) demonstrated that particulate matter (PM) generated by combustion of the two fuels induced different responses in in vitro and in vivo models. Concentrations of inflammatory mediators (Interleukin-6, IL-6; Interferon-gamma-induced Protein 10, IP-10; Granulocyte-stimulating factor, G-CSF) in the medium of B20-treated cells and in bronchoalveolar lavage fluid of mice exposed to B20 were ∼20-30% higher than control or B0 PM, suggesting that addition of biodiesel to diesel fuels will reduce PM emissions but not necessarily adverse health outcomes.


Assuntos
Biocombustíveis , Gasolina/análise , Glycine max/química , Inflamação/patologia , Tamanho da Partícula , Emissões de Veículos/análise , Animais , Antioxidantes/metabolismo , Biocombustíveis/toxicidade , Líquido da Lavagem Broncoalveolar/citologia , Contagem de Células , Linhagem Celular , Quimiocinas/metabolismo , Feminino , Humanos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Material Particulado/análise , Material Particulado/toxicidade , Emissões de Veículos/toxicidade
20.
Cytokine ; 60(3): 718-30, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23017228

RESUMO

Inflammatory responses of THP-1 cells (macrophage cell line) exposed to chrysotile asbestos (Chry) and Libby six-mix (LIB) and the subsequent impact on bronchial epithelial cells were determined. Direct treatment of THP-1 cells with Chry caused cell death, activation of caspase-1 and release of IL-1ß, while the addition of caspase-1 inhibitor, Z-YVAD-FMK, reduced IL-1ß, suggesting that Chry activated the caspase-1 mediated Nod-like receptor protein 3 (NLRP3) inflammasome; by comparison, LIB had less effects on all of these parameters. Expression of antioxidant enzymes, protein oxidation and nitration, and lipid peroxides in THP-1 cells treated with the two particles suggest that LIB generated more reactive oxygen species (ROS) than the same dose of Chry. Differences in fiber length and surface area suggest a possible role for particulate size in the differential activation of the inflammasome. BEAS-2B cells, representing the bronchial epithelium, treated with supernatants of medium from Chry- or LIB-treated THP-1 cells (conditioned medium) activated the MAPK cascade, increased phosphorylation of ERK and Cot (MAP3K8), increased AP-1 binding activity and induced IL-6 release. To verify that IL-1ß from THP-1 cells was responsible for activation of BEAS-2B, conditioned medium with added IL-1Ra, an IL-1ß antagonist, was applied to BEAS-2B. Results show that IL-1Ra attenuated effects of conditioned medium, supporting a role of IL-1ß, as a secondary mediator, in the transduction of inflammatory signaling from the macrophage to epithelial cells. The effects of LIB-conditioned medium appeared to be less dependent on IL-1ß. In conclusion, Chry and LIB induce differential inflammatory responses in THP-1 cells that subsequently lead to differential effects in epithelial cells.


Assuntos
Amiantos Anfibólicos/toxicidade , Asbestos Serpentinas/toxicidade , Células Epiteliais/efeitos dos fármacos , Inflamassomos/imunologia , Macrófagos/imunologia , Clorometilcetonas de Aminoácidos/farmacologia , Brônquios/efeitos dos fármacos , Proteínas de Transporte/efeitos dos fármacos , Proteínas de Transporte/metabolismo , Caspase 1/metabolismo , Linhagem Celular , Meios de Cultivo Condicionados/farmacologia , Células Epiteliais/imunologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Proteína Antagonista do Receptor de Interleucina 1/farmacologia , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Fosforilação , Proteínas Proto-Oncogênicas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição AP-1/metabolismo
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