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1.
Nat Commun ; 11(1): 4951, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009382

RESUMO

Immunogenic cell death (ICD) and tumour-infiltrating T lymphocytes are severely weakened by elevated reactive oxygen species (ROS) in the tumour microenvironment. It is therefore of critical importance to modulate the level of extracellular ROS for the reversal of immunosuppressive environment. Here, we present a tumour extracellular matrix (ECM) targeting ROS nanoscavenger masked by pH sensitive covalently crosslinked polyethylene glycol. The nanoscavenger anchors on the ECM to sweep away the ROS from tumour microenvironment to relieve the immunosuppressive ICD elicited by specific chemotherapy and prolong the survival of T cells for personalized cancer immunotherapy. In a breast cancer model, elimination of the ROS in tumour microenvironment elicited antitumour immunity and increased infiltration of T lymphocytes, resulting in highly potent antitumour effect. The study highlights a strategy to enhance the efficacy of cancer immunotherapy by scavenging extracellular ROS using advanced nanomaterials.


Assuntos
Antineoplásicos/farmacologia , Espaço Extracelular/metabolismo , Depuradores de Radicais Livres/metabolismo , Morte Celular Imunogênica , Espécies Reativas de Oxigênio/metabolismo , Animais , Linhagem Celular Tumoral , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Proteína HMGB1/metabolismo , Morte Celular Imunogênica/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Polietilenoglicóis/química , Microambiente Tumoral/efeitos dos fármacos
2.
J Environ Qual ; 49(5): 1384-1395, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33016445

RESUMO

Nutrients excreted from animals affect the nutritive value of manure as a soil amendment as well as the composition of gases emitted from manure storage facilities. There is a dearth of information, however, on how diet type in combination with dietary particle size affects nutrients deposited into manure storage facilities and how this affects manure composition and gas emissions. To fill this knowledge gap, an animal feeding trial was performed to evaluate potential interactive effects between feed particle size and diet composition on manure characteristics and manure-derived gaseous emissions. Forty-eight finishing pigs housed in individual metabolism crates that allowed for daily collection of urine and feces were fed diets differing in fiber content and particle size. Urine and feces were collected and stored in 446-L stainless steel containers for 49 d. There were no interactive effects between diet composition and feed particle size on any manure or gas emission parameter measured. In general, diets higher in fiber content increased manure nitrogen (N), carbon (C), and total volatile fatty acid (VFA) concentrations and increased manure VFA emissions but decreased manure ammonia emissions. Decreasing the particle size of the diet lowered manure N, C, VFAs, phenolics, and indole concentrations and decreased manure emissions of total VFAs. Neither diet composition nor particle size affected manure greenhouse gas emissions.


Assuntos
Dieta/veterinária , Esterco , Ração Animal/análise , Animais , Gases , Tamanho da Partícula , Suínos
3.
Cells ; 9(9)2020 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-32899484

RESUMO

Hybrid nanoparticles from lipidic and polymeric components were assembled to serve as vehicles for the transfection of messenger RNA (mRNA) using different portions of the cationic lipid DOTAP (1,2-Dioleoyl-3-trimethylammonium-propane) and the cationic biopolymer protamine as model systems. Two different sequential assembly approaches in comparison with a direct single-step protocol were applied, and molecular organization in correlation with biological activity of the resulting nanoparticle systems was investigated. Differences in the structure of the nanoparticles were revealed by thorough physicochemical characterization including small angle neutron scattering (SANS), small angle X-ray scattering (SAXS), and cryogenic transmission electron microscopy (cryo-TEM). All hybrid systems, combining lipid and polymer, displayed significantly increased transfection in comparison to lipid/mRNA and polymer/mRNA particles alone. For the hybrid nanoparticles, characteristic differences regarding the internal organization, release characteristics, and activity were determined depending on the assembly route. The systems with the highest transfection efficacy were characterized by a heterogenous internal organization, accompanied by facilitated release. Such a system could be best obtained by the single step protocol, starting with a lipid and polymer mixture for nanoparticle formation.


Assuntos
Biopolímeros/química , Lipídeos/química , Nanopartículas/química , RNA Mensageiro/metabolismo , Transfecção/métodos , Animais , Linhagem Celular , Ácidos Graxos Monoinsaturados/química , Feminino , Heparina/química , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Imagem Óptica , Tamanho da Partícula , Compostos de Amônio Quaternário/química , RNA Mensageiro/química
4.
Zhongguo Zhong Yao Za Zhi ; 45(15): 3672-3680, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32893557

RESUMO

In order to improve the supersaturation and maintenance time of drug dispersion in curcumin self-nanoemulsion(CUR-SNEDDS), precipitation inhibitors(PPIs) were introduced to prepare curcumin supersaturated self-emulsion(CUR-SSNEDDS). The composition of CUR-SNEDDS prescriptions was selected through the solubility test, the compatibility of oil phase and surfactant, the investigation of the emulsifying ability of the surfactant and the drawing of the pseudo-ternary phase diagram. Analytic hierarchy process was used in combination with central composite design-response surface method to optimize the prescription. The type and dosage of precipitation inhibitors(PPIs) were selected to maintain the supersaturated concentration and duration of CUR in artificial gastrointestinal fluids. At the same time, polarizing microscope was used to evaluate the crystallization inhibition effect and the quality and in vitro release behavior of CUR-SSNEDDS. The prepared CUR-SSNEDDS prescription was capryol 90-kolliphor RH40-transcutol HP-Soluplus(7.93∶66.71∶25.36∶5), with the drug loading of(65.12±1.25) mg·g~(-1). CUR-SSNEDDS was transparent yellow, and the nanoemulsion droplets were spherical with uniform distribution. The emulsification time was(21.02±0.13) s, the average particle size was(57.03±0.35) nm, the polydispersity index(PDI) was(0.23 ± 0.01), and the Zeta potential was(-18.10±1.30) mV. CUR-SSNEDDS significantly inhibited the generation and growth of crystals after in vitro dilution. The supersaturation could be maintained above 10 within 2 h, and the dissolution rate and degree of CUR in artificial gastrointestinal fluid were significantly increased. Soluplus could effectively maintain the supersaturated state of CUR and enhance CUR dissolution in vitro.


Assuntos
Curcumina , Nanopartículas , Disponibilidade Biológica , Emulsões , Tamanho da Partícula , Solubilidade , Tensoativos
5.
J Environ Sci (China) ; 97: 149-161, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32933730

RESUMO

Transboundary and domestic aerosol transport during 2018-2019 affecting Bangkok air quality has been investigated. Physicochemical characteristics of size-segregated ambient particles down to nano-particles collected during 2017 non-haze and 2018-2019 haze periods were analyzed. The average PM2.5 concentrations at KU and KMUTNB sites in Bangkok, Thailand during the haze periods were about 4 times higher than in non-haze periods. The highest average organic carbon and elemental carbon concentrations were 4.6 ± 2.1 µg/m3 and 1.0 ± 0.4 µg/m3, respectively, in PM0.5-1.0 range at KU site. The values of OC/EC and char-EC/soot-EC ratios in accumulation mode particles suggested the significant influence of biomass burning, while the nuclei and coarse mode particles were from mixed sources. PAH concentrations during 2018-2019 haze period at KU and KMUTNB were 3.4 ± 0.9 ng/m3 and 1.8 ± 0.2 ng/m3, respectively. The PAH diagnostic ratio of PM2.5 also suggested the main contributions were from biomass combustion. This is supported by the 48-hrs backward trajectory simulation. The higher PM2.5 concentrations during 2018-2019 haze period are also associated with the meteorological conditions that induce thermal inversions and weak winds in the morning and evening. Average values of benzo(a)pyrene toxic equivalency quotient during haze period were about 3-6 times higher than during non-haze period. This should raise a concern of potential human health risk in Bangkok and vicinity exposing to fine and ultrafine particulate matters in addition to regular exposure to traffic emission.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar , Aerossóis/análise , Biomassa , Carbono/análise , Monitoramento Ambiental , Humanos , Tamanho da Partícula , Material Particulado/análise , Estações do Ano , Tailândia
6.
Chemosphere ; 254: 126608, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957262

RESUMO

Al2O3 Nanoparticles (Al2O3-NPs) have been widely used because of their unique physical and chemical properties, and Al2O3-NPs can be released into the environment directly or indirectly. Our previous research found that 13 nm Al2O3-NPs can induce neural cell death and autophagy in primarily cultured neural cells in vitro. The aim of this study was to determine where Al2O3-NPs at 13 nm particle size can cause neural cells in vivo and assess related behavioural changes and involved potential mechanisms. Zebrafish from embryo to adult were selected as animal models. Learning and memory as functional indicators of neural cells in zebrafish were measured during the development from embryo to adult. Our results indicate that Al2O3-NPs treatment in zebrafish embryos stages can cause the accumulation of aluminium content in zebrafish brain tissue, leading to progressive impaired neurodevelopmental behaviours and latent learning and memory performance. Additionally, oxidative stress and disruption of dopaminergic transmission in zebrafish brain tissues are correlated with the dose-dependent and age-dependent accumulation of aluminium content. Moreover, the number of neural cells in the telencephalon tissue treated with Al2O3-NPs significantly declined, and the ultramicroscopic morphology indicated profound autophagy alternations. The results suggest that Al2O3-NPs has dose-dependent and time-dependent progressive damage on learning and memory performance in adult zebrafish when treated in embryos. This is the first study of the effects of Al2O3-NPs on learning and memory during the development of zebrafish from embryo to adult.


Assuntos
Óxido de Alumínio/toxicidade , Aprendizagem/efeitos dos fármacos , Memória/efeitos dos fármacos , Nanopartículas/toxicidade , Alumínio/farmacologia , Óxido de Alumínio/química , Animais , Embrião não Mamífero , Nanopartículas Metálicas , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Peixe-Zebra/embriologia
7.
Biomed Environ Sci ; 33(8): 583-592, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32933610

RESUMO

Objective: To screen the differentially expressed proteins (DEPs) in human bronchial epithelial cells (HBE) treated with atmospheric fine particulate matter (PM 2.5). Methods: HBE cells were treated with PM 2.5 samples from Shenzhen and Taiyuan for 24 h. To detect overall protein expression, the Q Exactive mass spectrometer was used. Gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG), and Perseus software were used to screen DEPs. Results: Overall, 67 DEPs were screened in the Shenzhen sample-treated group, of which 46 were upregulated and 21 were downregulated. In total, 252 DEPs were screened in the Taiyuan sample-treated group, of which 134 were upregulated and 118 were downregulated. KEGG analysis demonstrated that DEPs were mainly enriched in ubiquitin-mediated proteolysis and HIF-1 signal pathways in Shenzhen PM 2.5 samples-treated group. The GO analysis demonstrated that Shenzhen sample-induced DEPs were mainly involved in the biological process for absorption of various metal ions and cell components. The Taiyuan PM 2.5-induced DEPs were mainly involved in biological processes of protein aggregation regulation and molecular function of oxidase activity. Additionally, three important DEPs, including ANXA2, DIABLO, and AIMP1, were screened. Conclusion: Our findings provide a valuable basis for further evaluation of PM 2.5-associated carcinogenesis.


Assuntos
Poluentes Atmosféricos/análise , Brônquios/metabolismo , Células Epiteliais/metabolismo , Expressão Gênica/efeitos dos fármacos , Material Particulado/análise , Brônquios/efeitos dos fármacos , Biologia Computacional , Células Epiteliais/efeitos dos fármacos , Humanos , Espectrometria de Massas , Tamanho da Partícula , Proteômica
8.
Nat Commun ; 11(1): 4836, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32973157

RESUMO

From viruses to nanoparticles, constructs functionalized with multiple ligands display peculiar binding properties that only arise from multivalent effects. Using statistical mechanical modelling, we describe here how multivalency can be exploited to achieve what we dub range selectivity, that is, binding only to targets bearing a number of receptors within a specified range. We use our model to characterise the region in parameter space where one can expect range selective targeting to occur, and provide experimental support for this phenomenon. Overall, range selectivity represents a potential path to increase the targeting selectivity of multivalent constructs.


Assuntos
Entropia , Ligantes , Nanopartículas/química , Fenômenos Biofísicos , Modelos Teóricos , Tamanho da Partícula
9.
BMJ Open ; 10(8): e039454, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32753454

RESUMO

OBJECTIVE: There are widespread shortages of personal protective equipment as a result of the COVID-19 pandemic. Reprocessing filtering facepiece particle (FFP)-type respirators may provide an alternative solution in keeping healthcare professionals safe. DESIGN: Prospective, bench-to-bedside. SETTING: A primary care-based study using FFP-2 respirators without exhalation valve (3M Aura 1862+ (20 samples), Maco Pharma ZZM002 (14 samples)), FFP-2 respirators with valve (3M Aura 9322+ (six samples) and San Huei 2920V (16 samples)) and valved FFP type 3 respirators (Safe Worker 1016 (10 samples)). INTERVENTIONS: All masks were reprocessed using a medical autoclave (17 min at 121°C with 34 min total cycle time) and subsequently tested up to three times whether these respirators retained their integrity (seal check and pressure drop) and ability to filter small particles (0.3-5.0 µm) in the laboratory using a particle penetration test. RESULTS: We tested 33 respirators and 66 samples for filter capacity. All FFP-2 respirators retained their shape, whereas half of the decontaminated FFP-3 respirators showed deformities and failed the seal check. The filtering capacity of the 3M Aura 1862 was best retained after one, two and three decontamination cycles (0.3 µm: 99.3%±0.3% (new) vs 97.0±1.3, 94.2±1.3% or 94.4±1.6; p<0.001). Of the other FFP-2 respirators, the San Huei 2920 V had 95.5%±0.7% at baseline vs 92.3%±1.7% vs 90.0±0.7 after one-time and two-time decontaminations, respectively (p<0.001). The tested FFP-3 respirator (Safe Worker 1016) had a filter capacity of 96.5%±0.7% at baseline and 60.3%±5.7% after one-time decontamination (p<0.001). Breathing and pressure resistance tests indicated no relevant pressure changes between respirators that were used once, twice or thrice. CONCLUSION: This small single-centre study shows that selected FFP-2 respirators may be reprocessed for use in primary care, as the tested masks retain their shape, ability to retain particles and breathing comfort after decontamination using a medical autoclave.


Assuntos
Infecções por Coronavirus , Descontaminação/métodos , Reutilização de Equipamento , Segurança de Equipamentos , Máscaras/normas , Exposição Ocupacional/prevenção & controle , Pandemias , Pneumonia Viral , Dispositivos de Proteção Respiratória/normas , Filtros de Ar , Betacoronavirus , Infecções por Coronavirus/virologia , Pessoal de Saúde , Humanos , Tamanho da Partícula , Equipamento de Proteção Individual/normas , Pneumonia Viral/virologia , Atenção Primária à Saúde , Estudos Prospectivos , Ventiladores Mecânicos
10.
Sci Total Environ ; 737: 140100, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32783832

RESUMO

BACKGROUND: Fine particulate matter (PM2.5) air pollution has been associated with increased risks of acute myocardial infarction (AMI), but it remains unknown about the potentially differentiated effects of size-fractionated particulate matter on AMI risk. OBJECTIVE: To identify the specific size ranges that dominate the effects of particulate matter on AMI onset. METHODS: We conducted a time-series study in Shanghai, China from January 2014 to December 2018. We evaluated particle size distribution of 0.01 µm to 2.5 µm from an environmental supersite and AMI emergency hospitalizations from the largest cardiovascular hospital in Shanghai. We used over-dispersed generalized additive models to estimate the associations of size-fractionated particle number concentrations (PNC) with AMI and its types. RESULTS: We identified a total of 4720 AMI emergency hospitalizations. PM2.5 was significantly associated with increased AMI risk on the concurrent day. The associations were significant only for PNC < 0.3 µm. For an IQR increase of PNCs for size ranges 0.01-0.03 µm, 0.03-0.05 µm, 0.05-0.10 µm and 0.10-0.30 µm, AMI hospitalizations increased by 6.68% (95% CI: 2.77%, 10.74%), 6.53% (95% CI: 2.08%, 11.17%), 5.78% (95% CI: 0.92%, 10.88%) and 5.92% (95% CI: 1.31%, 10.74%), respectively. The associations of PNC < 0.05 µm remained significant when adjusting for other air pollutants. There were consistently much stronger associations of particles with ST-segment elevation AMI than those with non-ST-segment elevation AMI. CONCLUSIONS: This epidemiological investigation suggested that ultrafine particles, especially those <0.05 µm, may be mainly responsible for the acute AMI risk induced by PM2.5.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Infarto do Miocárdio , China , Hospitalização , Humanos , Tamanho da Partícula , Material Particulado/análise
11.
Int J Nanomedicine ; 15: 5671-5685, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32821096

RESUMO

Aim: The aim of the current work was to develop vardenafil hydrochloride (VRD)-loaded ethosome-derived invasomes as a possible transdermal system which could be used for patients suffering from pulmonary arterial hypertension. Methods: VRD-loaded ethosomes were developed at three concentrations of phosphatidylcholine (5, 10 and 15 mg/mL) and three percentages of ethanol (20%, 30% and 40%, v/v). The best achieved VRD-loaded ethosomes (ETH9) were optimized to invasomes via incorporation of terpenes (limonene, cineole and a 1:1 mixture) at three concentrations (0.5%, 1% and 2%, v/v). All systems were evaluated for vesicle size, zeta potential, drug entrapment efficiency (EE%), cumulative drug permeated percentages after 0.5hrs (Q0.5h) and 12hrs (Q12h) and steady-state flux (Jss). The optimized system (ETH9-INV8) was further characterized for morphology, histopathology and confocal laser scanning microscopy (CLSM). Physiologically based pharmacokinetic (PBPK) modeling was employed to estimate VRD pharmacokinetic parameters from the optimized transdermal system and an oral aqueous drug dispersion, in adults and geriatrics. Results: The optimized invasomal system (ETH9-INV8) was characterized with spherical vesicles (159.9 nm) possessing negative zeta potential (-20.3 mV), promising EE% (81.3%), low Q0.5h (25.4%), high Q12h (85.3%) and the largest steady-state flux (6.4 µg.cm-2h-1). Following a leave-on period of 12hrs in rats, it showed minor histopathologic changes. CLSM studies proved its ability to deeply permeate rat skin. Lower Cmax values, delayed Tmax estimates and greater AUC0-24h folds in adults and geriatrics (≈ 2.18 and 1.69, respectively) were estimated following the transdermal application of ETH9-INV8 system. Conclusion: ETH9-INV8 is a promising transdermal system for VRD.


Assuntos
Sistemas de Liberação de Medicamentos , Etanol/química , Geriatria , Modelos Biológicos , Dicloridrato de Vardenafila/administração & dosagem , Dicloridrato de Vardenafila/farmacocinética , Administração Cutânea , Animais , Lipossomos , Masculino , Microscopia Confocal , Tamanho da Partícula , Permeabilidade , Ratos Wistar , Absorção Cutânea , Eletricidade Estática
12.
Int J Nanomedicine ; 15: 5783-5802, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32821101

RESUMO

Nanoparticles (NPs) are highly potent tools for the diagnosis of diseases and specific delivery of therapeutic agents. Their development and application are scientifically and industrially important. The engineering of NPs and the modulation of their in vivo behavior have been extensively studied, and significant achievements have been made in the past decades. However, in vivo applications of NPs are often limited by several difficulties, including inflammatory responses and cellular toxicity, unexpected distribution and clearance from the body, and insufficient delivery to a specific target. These unfavorable phenomena may largely be related to the in vivo protein-NP interaction, termed "protein corona." The layer of adsorbed proteins on the surface of NPs affects the biological behavior of NPs and changes their functionality, occasionally resulting in loss-of-function or gain-of-function. The formation of a protein corona is an intricate process involving complex kinetics and dynamics between the two interacting entities. Structural changes in corona proteins have been reported in many cases after their adsorption on the surfaces of NPs that strongly influence the functions of NPs. Thus, understanding of the conformational changes and unfolding process of proteins is very important to accelerate the biomedical applications of NPs. Here, we describe several protein corona characteristics and specifically focus on the conformational fluctuations in corona proteins induced by NPs.


Assuntos
Nanopartículas/química , Conformação Proteica , Coroa de Proteína/química , Humanos , Tamanho da Partícula , Ligação Proteica , Propriedades de Superfície
14.
J Environ Manage ; 271: 111021, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32778302

RESUMO

Clarifiers integrating radial cartridge filtration (RCF) are a combined unit operation variant of millennia-old sedimentation-filtration systems. Similarly, RCF is a primarily horizontal flow variant with flow orthogonal to gravity and a radial velocity gradient, in contrast to traditional deep-bed vertical filtration. These granular filters function at lower finite granular Reynolds numbers. A proposed computational fluid dynamics framework, implementing the Navier-Stokes equations, couples a pore-scale filter model with a macroscopic scale sedimentation-filtration model to create a tool examining non-Brownian particle separation. Validation is conducted using previous physical testing from a full-scale sedimentation-filtration system under steady flow and particulate loads. Model results illustrate a two-zone filtration structure with respect to particle diameter, similar to vertical filtration. The computational tool predicts particulate matter separation of 86.1% compared to 87.8% for physical testing. The physical-based computational framework does not need high-level calibration as compared to analytical, lumped, or empirical models; conferring direct extensibility to similar unit operation systems. The novel multi-scale tool simulates particulate matter fate in a modern re-incarnation of a sedimentation-filtration unit operation. The tool functions as an adjuvant that complements regulatory or certification testing. The tool can provide guidance for design or maintenance as well as system management with respect to particle fate in, and breakthrough from, granular filters in a combined unit operation.


Assuntos
Filtração , Hidrodinâmica , Modelos Teóricos , Tamanho da Partícula , Material Particulado
16.
Int J Nanomedicine ; 15: 4825-4845, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32753868

RESUMO

Background: Nanosized drug delivery systems (NDDSs) have shown excellent prospects in tumor therapy. However, insufficient penetration of NDDSs has significantly impeded their development due to physiological instability and low passive penetration efficiency. Methods: Herein, we prepared a core cross-linked pullulan-modified nanosized system, fabricated by visible-light-induced diselenide bond cross-linked method for transporting ß-Lapachone and doxorubicin prodrug (boronate-DOX, BDOX), to improve the physiological stability of the NDDSs for efficient passive accumulation in tumor blood vessels (ß-Lapachone/BDOX-CCS). Additionally, ultrasound (US) was utilized to transfer ß-Lapachone/BDOX-CCS around the tumor vessel in a relay style to penetrate the tumor interstitium. Subsequently, ß-Lapachone enhanced ROS levels by overexpressing NQO1, resulting in the transformation of BDOX into DOX. DOX, together with abundant levels of ROS, achieved synergistic tumor therapy. Results: In vivo experiments demonstrated that ultrasound (US) + cross-linked nanosized drug delivery systems (ß-Lapachone/BDOX-CCS) group showed ten times higher DOX accumulation in the tumor interstitium than the non-cross-linked (ß-Lapachone/BDOX-NCS) group. Conclusion: Thus, this strategy could be a promising method to achieve deep penetration of NDDSs into the tumor.


Assuntos
Doxorrubicina/uso terapêutico , Nanopartículas/química , Naftoquinonas/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Pró-Fármacos/uso terapêutico , Ultrassonografia , Animais , Ácidos Borônicos/química , Permeabilidade Capilar/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Reagentes para Ligações Cruzadas/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Endocitose/efeitos dos fármacos , Feminino , Glucanos/química , Células Hep G2 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Naftoquinonas/farmacocinética , Tamanho da Partícula , Pró-Fármacos/farmacocinética , Espécies Reativas de Oxigênio/metabolismo , Distribuição Tecidual/efeitos dos fármacos
17.
Nat Commun ; 11(1): 4062, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32811826

RESUMO

Influenza viruses are presumed, but not conclusively known, to spread among humans by several possible routes. We provide evidence of a mode of transmission seldom considered for influenza: airborne virus transport on microscopic particles called "aerosolized fomites." In the guinea pig model of influenza virus transmission, we show that the airborne particulates produced by infected animals are mainly non-respiratory in origin. Surprisingly, we find that an uninfected, virus-immune guinea pig whose body is contaminated with influenza virus can transmit the virus through the air to a susceptible partner in a separate cage. We further demonstrate that aerosolized fomites can be generated from inanimate objects, such as by manually rubbing a paper tissue contaminated with influenza virus. Our data suggest that aerosolized fomites may contribute to influenza virus transmission in animal models of human influenza, if not among humans themselves, with important but understudied implications for public health.


Assuntos
Fômites , Vírus da Influenza A , Influenza Humana/transmissão , Influenza Humana/virologia , Material Particulado , Aerossóis , Animais , Modelos Animais de Doenças , Feminino , Cobaias , Humanos , Vírus da Influenza A Subtipo H3N2 , Infecções por Orthomyxoviridae/virologia , Tamanho da Partícula
18.
Environ Pollut ; 266(Pt 1): 115261, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32745902

RESUMO

Indoor plants can be used to monitor atmospheric particulates. Here, we report the label-free detection of combustion-derived particles (CDPs) on plants as a monitoring tool for indoor pollution. First, we measured the indoor CDP deposition on Atlantic ivy leaves (Hedera hibernica) using two-photon femtosecond microscopy. Subsequently, to prove its effectiveness for using it as a monitoring tool, ivy plants were placed near five different indoor sources. CDP particle area and number were used as output metrics. CDP values ranged between a median particle area of 0.45 × 102 to 1.35 × 104 µm2, and a median particle number of 0.10 × 102 to 1.42 × 10³ particles for the indoor sources: control (greenhouse) < milling machine < indoor smokers < wood stove < gas stove < laser printer. Our findings demonstrate that Atlantic ivy, combined with label-free detection, can be effectively used in indoor atmospheric monitoring studies.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Carvão Mineral , Monitoramento Ambiental , Tamanho da Partícula , Material Particulado/análise
19.
Environ Pollut ; 266(Pt 2): 115046, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32791467

RESUMO

Conducting studies on sharp particulate matter (PM) gradients in Asian residential communities is difficult due to their complex building arrangements and various emission sources, particularly road traffic. In this study, a synthetic methodology, combining numerical simulations and minor field observations, was set up to investigate the dispersion of traffic-related PM in a typical Asian residential community and its contribution to PM exposure. A Lagrangian particle model (GRAL) was applied to estimate the spatiotemporal variation of the traffic-related PM increments within the community. A detailed topography dataset with 5 m horizontal resolution was used to simulate a micro-scale flow field. The model performance was comprehensively validated using both in-situ and mobile observations. The coefficient of determination (R2) of the simulated vs. observed PM2.5 reached 0.81 by an artery road, and 0.85 in alleys without significant road traffic. The maximum increments of kerbside PM exposure concentration contributed by road traffic during rush hour were found to be 38% (PM10) and 40% (PM2.5). This synthetic method was used to assess the impact of synoptic wind and canyon orientation on residents' PM2.5 exposure related to traffic exhaust. Perfect exponential decay curves of traffic-related PM2.5 were found within canyons. The decrease of road-traffic PM2.5 on five different floor levels, compared with that on kerbside levels, ranged between 42% and 100%. The results demonstrated that in complex Asian communities, Lagrangian particle models such as GRAL can simulate the spatial distribution of PM10 and PM2.5 and assess the residents' outdoor exposure.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Tamanho da Partícula , Material Particulado/análise , Emissões de Veículos/análise , Vento
20.
Environ Pollut ; 266(Pt 3): 115271, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32814272

RESUMO

The ability of particulate matter (PM) to induce oxidative stress is frequently estimated by acellular oxidative potential (OP) assays, such as ascorbic acid (AA) and 1,4-dithiothreitol (DTT), used as proxy of reactive oxygen species (ROS) generation in biological systems, and particle-bound ROS measurement, such as 2',7'-dichlorodihydrofluorescein (DCFH) assay. In this study, we evaluated the spatial and size distribution of OP results obtained by three OP assays (OPAA, OPDCFH and OPDTT), to qualitative identify the relative relevance of single source contributions in building up OP values and to map the PM potential to induce oxidative stress in living organisms. To this aim, AA, DCFH and DTT assays were applied to size-segregated PM samples, collected by low-pressure cascade impactors, and to PM10 samples collected at 23 different sampling sites (about 1 km between each other) in Terni, an urban and industrial hot-spot of Central Italy, by using recently developed high spatial resolution samplers of PM, which worked in parallel during three monitoring periods (February, April and December 2017). The sampling sites were chosen for representing the main spatially disaggregated sources of PM (vehicular traffic, rail network, domestic heating, power plant for waste treatment, steel plant) present in the study area. The obtained results clearly showed a very different sensitivity of the three assays toward each local PM source. OPAA was particularly sensitive toward coarse particles released from the railway, OPDCFH was sensible to fine particles released from the steel plant and domestic biomass heating, and OPDTT was quite selectively sensitive toward the fine fraction of PM released by industrial and biomass burning sources.


Assuntos
Poluentes Atmosféricos/análise , Material Particulado/análise , Monitoramento Ambiental , Itália , Oxirredução , Estresse Oxidativo , Tamanho da Partícula
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