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1.
J Agric Food Chem ; 67(38): 10587-10594, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31497957

RESUMO

Inefficient usage and overdosage of conventional pesticide formulations has resulted in large economic losses and environmental pollution due to their poor water solubility and weak adhesion to foliage. In order to develop a green and efficient pesticide formulation, a kind of alkyd resin (AR) based on vegetable oil was first synthesized and used to fabricate the lambda-cyhalothrin/AR (LC/AR) nanoemulsion via in situ phase inverse emulsification, and its properties were then investigated. Results showed that the particle size of the LC/AR nanoemulsion was 50-150 nm with maximum LC loading capacity of as much as 40.9 wt %, high encapsulation efficiency >90%, and great stability in multiple environments. The LC/AR nanoemulsion exhibited better controlled release characteristics compared with LC commercial formulations, and a stronger adhesion on the foliage of the resulted nanoemulsion was also observed, which was attributed to low surface tension and strong interactions with foliar surfaces.


Assuntos
Preparações de Ação Retardada/química , Composição de Medicamentos/métodos , Nitrilos/química , Praguicidas/química , Piretrinas/química , Emulsões/química , Tamanho da Partícula , Solubilidade
2.
Bioresour Technol ; 293: 122043, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31472406

RESUMO

The objective of this study was to investigate the effects of particle size reduction (20, 1, 0.15, and 0.075 mm) on biogas production from rice straw waste through batch anaerobic digestion experiments. To clarify the digestion mechanisms, the microbial community and rice straw properties including fractal dimension, dissolution abilities and the bio-liquefaction degree were determined. Particle size reduction of rice straw improved methane yield from 107 mL g-1 VS to 197 mL g-1 VS. The elevated digestion efficiency was attributed to the cellulose degradation (degradation rate from 27% to 93%) rather than hemicellulose or lignin. The comminution pretreatment improved the basic morphology, dissolution abilities and bio-liquefaction degree, which associated with the shifts in the bacterial community and the decreased bacterial diversity. These results suggested that particle size reduction of the rice straw in conjunction with optimized microbial growth could improve the methane yield in anaerobic digestion processes.


Assuntos
Oryza , Anaerobiose , Biocombustíveis , Metano , Tamanho da Partícula
3.
Top Curr Chem (Cham) ; 377(5): 25, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31529217

RESUMO

Metal-organic frameworks (MOFs) have gathered tremendous interest among researchers for their potential applications such as in storage and separation. While some progress has been made towards shaping of MOFs to realize industrial applications, the mechanical properties of MOFs remain more or less unexplored. Over the last decade, this area has witnessed a steady growth in terms of understanding the mechanical stability of MOFs and its consequence on their performance. In this review, the mechanical properties of the reported macroscopic shaped MOF structures (mainly granules, pellets, tablets, monoliths, and gels) are discussed. Conclusions are then drawn to determine which shapes and shaping techniques promise to meet industrial requirements on the basis of mechanical stability. Finally, future research directions are proposed to improve our understanding, and possibly enhance stability, by correlating the properties from microscopic single-crystalline level to the industrially relevant macroscopic polycrystalline scale.


Assuntos
Estruturas Metalorgânicas/química , Estrutura Molecular , Tamanho da Partícula , Porosidade , Propriedades de Superfície
4.
Top Curr Chem (Cham) ; 377(5): 27, 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31559502

RESUMO

The photocatalytic dehydrogenation of formic acid has recently emerged as an outstanding alternative to the traditional thermal catalysts widely applied in this reaction. The utilization of photocatalytic processes for the production of hydrogen is an appealing strategy that perfectly matches with the idea of a green and sustainable future energy scenario. However, it sounds easier than it is, and great efforts have been needed to design and develop highly efficient photocatalysts for the production of hydrogen from formic acid. In this work, some of the most representative strategies adopted for this application are reviewed, paying particular attention to systems based on TiO2, CdS and C3N4.


Assuntos
Formiatos/química , Hidrogênio/química , Catálise , Hidrogenação , Tamanho da Partícula , Processos Fotoquímicos
5.
Int J Nanomedicine ; 14: 4911-4929, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31456637

RESUMO

Background: Apocynin (APO) is a bioactive phytochemical with prominent anti-inflammatory and anti-oxidant activities. Designing a nano-delivery system targeted to potentiate the gastric antiulcerogenic activity of APO has not been investigated yet. Chitosan oligosaccharide (COS) is a low molecular weight chitosan and its oral nanoparticulate system for potentiating the antiulcerogenic activity of the loaded APO has been described here. Methods: COS-nanoparticles (NPs) loaded with APO (using tripolyphosphate [TPP] as a cross-linker) were prepared by ionic gelation method and fully characterized. The chosen formula was extensively evaluated regarding in vitro release profile, kinetic analysis, and stability at refrigerated and room temperatures. Ultimately, the in vivo antiulcerogenic activity against ketoprofen (KP)-induced gastric ulceration in rats was assessed by macroscopic parameters including Paul's index and antiulcerogenic activity, histopathological examination, immunohistochemical (IHC) evaluation of cyclooxygenase-2 (COX-2) expression level in ulcerated gastric tissue, and biochemical measurement of oxidative stress markers and nitric oxide (NO) levels. Results: The selected NPs formula with COS (0.5 % w/v) and TPP (0.1% w/v) was the most appropriate one with drug entrapment efficiency percentage of 35.06%, particle size of 436.20 nm, zeta potential of +38.20 mV, and mucoadhesive strength of 51.22%. It exhibited a biphasic in vitro release pattern as well as high stability at refrigerated temperature for a 6-month storage period. APO-loaded COS-NPs provoked marvelous antiulcerogenic activity against KP-induced gastric ulceration in rats compared with free APO treated group, which was emphasized by histopathological, IHC, and biochemical studies. Conclusion: In conclusion, APO-loaded COS-NPs could be considered as a promising oral phytopharmaceutical nanoparticulate system for management of gastric ulceration.


Assuntos
Acetofenonas/administração & dosagem , Acetofenonas/farmacologia , Quitosana/química , Mucosa Gástrica/efeitos dos fármacos , Nanopartículas/química , Oligossacarídeos/química , Compostos Fitoquímicos/administração & dosagem , Compostos Fitoquímicos/farmacologia , Acetofenonas/uso terapêutico , Administração através da Mucosa , Animais , Biomarcadores/metabolismo , Varredura Diferencial de Calorimetria , Ciclo-Oxigenase 2/metabolismo , Liberação Controlada de Fármacos , Cinética , Masculino , Nanopartículas/ultraestrutura , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Estômago/efeitos dos fármacos , Estômago/patologia , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/patologia , Suínos , Difração de Raios X
6.
Bioresour Technol ; 291: 121867, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31376671

RESUMO

Nitrous oxide (N2O) is a strong greenhouse gas that is produced in significant quantities through biological nitrogen removal processes in wastewater treatment plants; however, N2O generation within the internal micro-environment of activated sludge flocs (ASFs) is poorly understood. In this study, microelectrodes and molecular techniques were employed to investigate the concentrations of N2O and other chemicals and the composition and distribution of microbes within ASFs, respectively. The results showed that N2O generation was correlated with the ASF micro-environment, and was significantly influenced by the dissolved oxygen (DO) concentration of the bulk wastewater. Equal N2O, DO, NH4+-N, and NO3--N concentrations were found in small flocs (<100 µm). By contrast, higher N2O generation rates and lower DO, NH4+-N, and NO3--N concentrations were detected in the center of large flocs (>200 µm) compared with those at their surfaces. Microbial structures of varying particle sizes were distinct and depended on the micro-environmental characteristics.


Assuntos
Óxido Nitroso/metabolismo , Oxigênio/metabolismo , Esgotos , Nitrogênio/metabolismo , Tamanho da Partícula , Esgotos/química
7.
Chem Pharm Bull (Tokyo) ; 67(8): 801-809, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31366829

RESUMO

Granules prepared by a continuous twin screw granulator (TSG) were analyzed by X-ray micro-computed tomography (X-ray µCT) and the relationships between porosity of granules and granule properties were investigated. A model formulation containing ibuprofen, lactose monohydrate, microcrystalline cellulose, and hydroxypropyl cellulose was used. The porosity of granules was measured by X-ray µCT and mercury porosimetry. The data sets obtained by both methods showed linear correlation despite different values, which were attributed to the resolution of X-ray µCT and a low-signal-to-noise ratio of the original cross-sectional images. The porosity of granules measured by X-ray µCT decreased from 11-14 to 6-7% as liquid-to-solid ratio (L/S) increased, while the standard deviation (S.D.) of the porosity of individual granules decreased from 4-5 to 2%. L/S affected the porosity of granules. By contrast, the effect of screw speed was not significant. Pressure transmission, G, which indicates the liquid dispersion in wet kneaded masses, increased as the porosity of granules and the S.D. decreased. The cross-sectional images showed that granules were densified as L/S increased. Based on these results, the effect of L/S on the porosity of granules can be explained by liquid dispersion and densification of the wet granules. The porosity of granules measured by X-ray µCT showed good linear correlation with friability and drug dissolution rate (R2 = 0.9107 and 0.8834, respectively). This study revealed that the drug dissolution rate was regulated by a disintegration step in which the porosity of granules plays an important role.


Assuntos
Parafusos Ósseos , Tecnologia Farmacêutica , Microtomografia por Raio-X , Tamanho da Partícula , Porosidade , Propriedades de Superfície , Raios X
8.
J Agric Food Chem ; 67(33): 9371-9381, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31379162

RESUMO

A major obstacle to the clinical use of curcumin (CUR) is its reduced bioavailability because of the drug's hydrophobic nature, low intestinal absorption, and rapid metabolism. In this study, a novel oral drug delivery system was constructed for improving the stability and enhancing mucoadhesion of CUR in the gastrointestinal (GI) tract. First, CUR was encapsulated in the bovine serum albumin nanoparticles (CUR-BSA-NPs). Then, N-acetyl cysteine (NAC)-modified CUR-BSA-NPs (CUR-NBSA-NPs) were obtained. The average particle size and zeta potential of CUR-NBSA-NPs were 251.6 nm and -30.66 mV, respectively; encapsulation efficiency and drug loading were 85.79 and 10.9%, respectively. CUR-NBSA-NPs exhibited a sustained release property and prominently enhanced stability in simulated GI conditions. Additionally, enhanced mucoadhesion of CUR-NBSA-NPs was also observed. An MTT study showed that the CUR-NBSA-NPs were safe for oral administration. Overall, NAC-modified BSA-NPs may potentially serve as an oral vehicle for improving CUR stability in the GI tract and enhancing mucoadhesion.


Assuntos
Acetilcisteína/química , Curcumina/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/instrumentação , Trato Gastrointestinal/metabolismo , Nanopartículas/química , Soroalbumina Bovina/química , Animais , Células CACO-2 , Bovinos , Curcumina/metabolismo , Estabilidade de Medicamentos , Humanos , Tamanho da Partícula
9.
J Biomed Nanotechnol ; 15(10): 2121-2129, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31462376

RESUMO

To develop a vancomycin-loaded superparamagnetic chitosan nanoparticles (Vm-SPMCNs) system for the treatment of chronic pyogenic osteoarthrosis to avoid the critical side effects caused by the systemic administration of vancomycin, the preparation process of Vm-SPMCNs was optimized by the orthogonal array design method; the optimum parameters were 1.2 g of chitosan, 0.2 g of vancomycin, 0.3 g of magnetite (Fe3O4), 12 mL of glutaraldehyde and stirring at 400 rpm. The drug loading and encapsulation efficiencies of the optimum Vm-SPMCNs were 10.30 ± 0.42% and 79.02 ± 1.81%, respectively. The Fourier transform infrared spectra confirmed that vancomycin was successfully bound to the magnetic chitosan nanoparticles. The Vm-SPMCNs were superparamagnetic particles with a diameter of 207.2 nm. The results of in vitro release tests suggested that the Vm-SPMCNs could constantly release vancomycin to maintain the concentration above the minimum inhibitory concentration for ten days, and noninvasive external magnetic stimulation could modulate the release profile according to the actual therapeutic requirements.


Assuntos
Nanopartículas de Magnetita , Quitosana , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Vancomicina
10.
Pharm Res ; 36(10): 140, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31367876

RESUMO

PURPOSE: In order to overcome the obstacles and side effects of classical chemotherapy, numerous studies have been performed to develop the treatment based on targeted transport of active compounds directly to the site of action. Since tumor cells are featured with intensified glucose metabolism, we set out to develop innovative, glucose-modified PAMAM dendrimer for the delivery of doxorubicin to breast cancer cells. METHODS: PAMAM-dox-glc conjugate was synthesized and characterized by 1H NMR, FT-IR, size and zeta potential measurements. The drug release rate from conjugate was evaluated by dialysis under different pH conditions. The expression level of GLUT family receptors in cells cultured in full and glucose-deprived medium was evaluated by quantitative real-time RT-PCR and flow cytometry. The cytotoxicity of conjugate in presence or absence of GLUT1 inhibitors was determined by MTT assay. RESULTS: We showed that PAMAM-dox-glc conjugate exhibits pH-dependent drug release and increased cytotoxic activity compared to free drug in cells cultured in medium without glucose. Further, we proved that these cells overexpress transporters of GLUT family. The toxic effect of conjugate was eliminated by the application of specific GLUT1 inhibitors. CONCLUSION: Our findings revealed that the glucose moiety plays a crucial role in the recognition of cells with high expression of GLUT receptors. By selectively blocking GLUT1 transporter we showed its importance for the cytotoxic activity of PAMAM-dox-glc conjugate. These results suggest that PAMAM-glucose formulations may constitute an efficient platform for the specific delivery of anticancer drugs to tumor cells overexpressing transporters of GLUT family.


Assuntos
Antineoplásicos/farmacologia , Dendrímeros/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Transportador de Glucose Tipo 1/metabolismo , Glucose/efeitos adversos , Antineoplásicos/administração & dosagem , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Liberação Controlada de Fármacos , Regulação da Expressão Gênica , Glucose/química , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Tamanho da Partícula
11.
Pharm Res ; 36(10): 142, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31376020

RESUMO

BACKGROUND: With the recent approval of the first small interfering RNA (siRNA) therapeutic formulated as nanoparticles, there is increased incentive for establishing the factors of importance for the design of stable solid dosage forms of such complex nanomedicines. METHODS: The aims of this study were: (i) to identify factors of importance for the design of spray-dried siRNA-loaded lipidoid-poly(DL-lactic-co-glycolic acid) hybrid nanoparticles (LPNs), and (ii) to evaluate their influence on the resulting powders by using a quality-by-design approach. Critical formulation and process parameters were linked to critical quality attributes (CQAs) using design of experiments, and an optimal operating space (OOS) was identified. RESULTS: A series of CQAs were identified based on the quality target product profile. The loading (ratio of LPNs to the total solid content) and the feedstock concentration were determined as critical parameters, which were optimized systematically. Mannitol was chosen as stabilizing excipient due to the low water content of the resulting powders. The loading negatively affected the colloidal stability of the LPNs, whereas feedstock concentration correlated positively with the powder particle size. The optimal mannitol-based solid formulation, defined from the OOS, displayed a loading of 5% (w/w), mass median aerodynamic diameter of 3.3 ± 0.2 µm, yield of 60.6 ± 6.6%, and a size ratio of 1.15 ± 0.03. Dispersed micro-embedded LPNs had preserved physicochemical characteristics as well as in vitro siRNA release profile and gene silencing, as compared to non-spray-dried LPNs. CONCLUSION: The optimal solid dosage forms represent robust formulations suitable for higher scale-up manufacturing.


Assuntos
Dessecação/métodos , Lipídeos/química , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , RNA Interferente Pequeno/química , Administração por Inalação , Animais , Composição de Medicamentos , Excipientes/química , Inativação Gênica , Técnicas de Transferência de Genes , Manitol/química , Camundongos , Nanomedicina , Tamanho da Partícula , Pós , Células RAW 264.7 , RNA Interferente Pequeno/administração & dosagem , Solubilidade , Solventes/química
12.
Pharm Res ; 36(10): 143, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31385111

RESUMO

PURPOSE: Pancreatic Polypeptide-secreting tumor of the distal pancreas (PPoma) is a rare, difficult and indolent type of cancer with a survival rate of 5-year in only 10% of all cases. The PPoma is classified as a neuroendocrine tumor (NET) not functioning that overexpresses SSTR 2 (somatostatin receptor subtype 2). Thus, in order to improve the diagnosis of this type of tumor, we developed nanoparticulate drug carriers based on poly-lactic acid (PLA) polymer loaded with octreotide and radiolabeled with Technetium-99 m (99mTc). METHODS: PLA/PVA octreotide nanoparticles were developed by double-emulsion technique. These nanoparticles were characterized by Atomic Force Microscopy (AFM) and Dynamic Light Scattering (DLS) and radiolabeled with 99mTc by the direct via forming 99mTc-PLA/PVA octreotide nanoparticles. The safety of these nanosystems was evaluated by the MTT cell toxicity assay and their in vivo biodistribution was evaluated in xenografted inducted animals. RESULTS: The results showed that a 189 nm sized nanoparticle were formed with a PDI of 0,097, corroborating the monodispersive behavior. These nanoparticles were successfully radiolabeled with 99mTc showing uptake by the inducted tumor. The MTT assay corroborated the safety of the nanosystem for the cells. CONCLUSION: The results support the use of this nanosystem (99mTc-PLA/PVA octreotide nanoparticles) as imaging agent for PPoma. Graphical Abstract Polypeptide-Secreting Tumor of the Distal Pancreas (PPoma) Radiolabeled Nanoparticles for Imaging.


Assuntos
Carcinoma Ductal Pancreático/diagnóstico por imagem , Nanopartículas/química , Octreotida/química , Neoplasias Pancreáticas/diagnóstico por imagem , Polipeptídeo Pancreático/metabolismo , Poliésteres/química , Compostos Radiofarmacêuticos/química , Tecnécio/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/metabolismo , Octreotida/metabolismo , Pâncreas/diagnóstico por imagem , Pâncreas/metabolismo , Neoplasias Pancreáticas/metabolismo , Tamanho da Partícula , Cintilografia/métodos , Compostos Radiofarmacêuticos/metabolismo , Receptores de Somatostatina/genética , Receptores de Somatostatina/metabolismo , Distribuição Tecidual
13.
Pharm Res ; 36(10): 144, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31392417

RESUMO

PURPOSE: Boron neutron capture therapy (BNCT) has the potential to become a viable cancer treatment modality, but its clinical translation requires sufficient tumor boron delivery while minimizing nonspecific accumulation. METHODS: Thermal sensitive liposomes (TSLs) were designed to have a stable drug payload at physiological temperatures but engineered to have high permeability under mild hyperthermia. RESULTS: We found that TSLs improved the tumor-specific delivery of boronophenylalanine (BPA) and boronated 2-nitroimidazole derivative B-381 in D54 glioma cells. Uniquely, the 2-nitroimidazole moiety extended the tumor retention of boron content compared to BPA. CONCLUSION: This is the first study to show the delivery of boronated compounds using TSLs for BNCT, and these results will provide the basis of future clinical trials using TSLs for BNCT.


Assuntos
Compostos de Boro/química , Terapia por Captura de Nêutron de Boro , Lipossomos/química , Animais , Antineoplásicos/química , Compostos de Boro/administração & dosagem , Compostos de Boro/farmacocinética , Linhagem Celular Tumoral , Neoplasias do Sistema Nervoso Central/metabolismo , Doxorrubicina/química , Liberação Controlada de Fármacos , Feminino , Glioma/metabolismo , Humanos , Hipertermia Induzida , Camundongos Nus , Nitroimidazóis/administração & dosagem , Nitroimidazóis/química , Tamanho da Partícula , Fenilalanina/administração & dosagem , Fenilalanina/análogos & derivados , Fenilalanina/química , Fosfolipídeos/química , Temperatura Ambiente , Distribuição Tecidual
14.
J Biomed Nanotechnol ; 15(9): 1968-1981, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31387683

RESUMO

Primary open angle glaucoma (POAG) is the most common glaucoma type worldwide. The most significant risk factor of this type of glaucoma is the increased intraocular pressure (IOP) that may result in optic nerve damage and gradual but complete loss of vision. Reduction of IOP is the most important measure that should be taken into consideration during selection of glaucoma therapy. Several IOP-lowering medications are available in the drug market. Unfortunately, most of them associated with severe local and/or systemic adverse effects, short duration of action and poor patient compliance. In the current research we strive to develop a long acting, once daily, nanoparticle (NP)-based, ocular formulation loaded with R-801 (a newly discovered drug). Our NPs were prepared from carefully selected bioadhesive and biocompatible materials using double emulsification solvent diffusion method. This method of preparation was selected to obtain the highest encapsulation efficiency for our water-soluble drug and the smallest particle size for our NPs. Also, the NPs were incorporated in biocompatible and bioadhesive vehicles to achieve the required safety, biocompatibility and prolonged corneal contact time. Our formulations were subjected to various in vitro and in vivo evaluations that demonstrated their safety and ability to sustain the drug release, prolong corneal contact time, lower IOP in different animal models, and maintain the IOP at almost constant low value through the day without any fluctuation upon long-term daily application.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Nanopartículas , Animais , Humanos , Pressão Intraocular , Tamanho da Partícula
15.
J Agric Food Chem ; 67(37): 10432-10447, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31466447

RESUMO

A composite nanogel was developed for cyanidin-3-O-glucoside (C3G) delivery by combining Maillard reaction and heat gelation. The starting materials utilized were ovalbumin, dextran, and pectin. C3G-loaded nanogel was spherical with a diameter of ∼185 nm, which was maintained over a wide range of pH and NaCl concentrations. The composite nanogel enhanced the chemical stability of C3G under accelerated degradation models and a simulated gastrointestinal tract. Clathrin-mediated, caveolae-mediated, and macropinocytosis-related endocytosis contributed to the higher cellular uptake of nano-C3G than that of free-C3G. The apparent permeability coefficients of C3G increased 2.16 times after nanoencapsulation. The transcytosis of the C3G-bearing nanogel occurred primarily through the clathrin-related pathway and macropinocytosis and followed the "common recycling endosomes-endoplasmic reticulum-Golgi complex-basolateral plasma membrane" route. Moreover, nano-C3G was more efficient in restoring the viability of cells and activities of endogenous antioxidant enzymes than free-C3G in oxidative models, which may be attributed to the former's high cellular absorption.


Assuntos
Antocianinas/química , Antocianinas/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , Portadores de Fármacos/química , Glucosídeos/química , Glucosídeos/metabolismo , Células CACO-2 , Composição de Medicamentos , Estabilidade de Medicamentos , Trato Gastrointestinal/metabolismo , Géis/química , Géis/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Absorção Intestinal , Modelos Biológicos , Nanopartículas/química , Nanopartículas/metabolismo , Tamanho da Partícula
16.
J Agric Food Chem ; 67(37): 10470-10480, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31469565

RESUMO

Foodborne nanoparticles (FNPs) produced by roasting have attracted the attention of people, owing to their safety risk to body health. Herein, we reported the formation, physicochemical properties, elemental composition, biodistribution, and binding with human serum albumin (HSA) of FNPs extracted from roast squid. The results showed that the FNP size gradually decreased from 4.1 to 2.3 nm as the roasting temperature changed from 190 to 250 °C. The main component elements of FNPs are carbon, oxygen, and nitrogen, and the carbon and nitrogen contents of FNPs increased with the roasting temperature rising. The surface of FNPs contained hydroxyl, amino, and carboxyl functional groups. The FNPs can emit fluorescence in ultraviolet light and show excitation-dependent emission behavior. Furthermore, it was found that the FNPs derived from roast squid could be accumulated in the stomach, intestine, and brain of BALB/c mice after oral feeding. Static fluorescence quenching of HSA was found by the Stern-Volmer equation and ultraviolet-visible spectrum analysis after interaction with the FNPs. After the addition of FNPs, the α-helix content of HSA decreased and the morphological height of HSA increased, which indicated that the FNPs could cause structural changes in HSA. The atomic force microscopy characterization showed the formation of nanocorona between FNPs and HSA.


Assuntos
Decapodiformes/química , Nanopartículas/química , Nanopartículas/metabolismo , Albumina Sérica Humana/química , Animais , Culinária , Decapodiformes/metabolismo , Fluorescência , Temperatura Alta , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Microscopia de Força Atômica , Tamanho da Partícula , Ligação Proteica , Conformação Proteica , Albumina Sérica Humana/metabolismo , Distribuição Tecidual
17.
Toxicol Lett ; 315: 47-54, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31449845

RESUMO

Particulate matter with a diameter of less than 2.5 µm (PM2.5) easily deposits on lung alveoli and degrades human health. Surfactant protein A (SP-A) is the most abundant pulmonary surfactant protein stored in lamellar bodies (LBs) of alveolar epithelial type II cells. The impacts of PM2.5 on SP-A are multifaceted and intractable, and the underlying mechanism remains unclear. In this study, the expression and distribution of SP-A in Balb/c mice and A549 cells under PM2.5 exposure were investigated. The results showed that the low and medium concentration of PM2.5 gradually enhanced SP-A protein and mRNA expression, whereas the high concentration of PM2.5 conspicuously decreased SP-A protein but not its mRNA compared with the control. The trafficking of SP-A to LBs was gradually disturbed, and concomitantly, the lesions of LBs responsible for the transport and storage of SP-A protein were exacerbated with increased PM2.5 concentration. Reactive oxygen species production abundantly increased upon PM2.5 exposure, and it was antagonized by the oxidant inhibitor N-acetylcysteine. Subsequently, the injured LBs and the decrease in SP-A expression under exposure to the high concentration of PM2.5 were well rescued. The present study provides a new perspective to investigate the adverse effects of PM2.5 or diesel exhaust particles on other proteins transported to and stored in LBs.


Assuntos
Células Epiteliais Alveolares/metabolismo , Material Particulado/toxicidade , Alvéolos Pulmonares/fisiopatologia , Proteína A Associada a Surfactante Pulmonar/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Emissões de Veículos/toxicidade , Animais , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula
18.
N Engl J Med ; 381(8): 705-715, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31433918

RESUMO

BACKGROUND: The systematic evaluation of the results of time-series studies of air pollution is challenged by differences in model specification and publication bias. METHODS: We evaluated the associations of inhalable particulate matter (PM) with an aerodynamic diameter of 10 µm or less (PM10) and fine PM with an aerodynamic diameter of 2.5 µm or less (PM2.5) with daily all-cause, cardiovascular, and respiratory mortality across multiple countries or regions. Daily data on mortality and air pollution were collected from 652 cities in 24 countries or regions. We used overdispersed generalized additive models with random-effects meta-analysis to investigate the associations. Two-pollutant models were fitted to test the robustness of the associations. Concentration-response curves from each city were pooled to allow global estimates to be derived. RESULTS: On average, an increase of 10 µg per cubic meter in the 2-day moving average of PM10 concentration, which represents the average over the current and previous day, was associated with increases of 0.44% (95% confidence interval [CI], 0.39 to 0.50) in daily all-cause mortality, 0.36% (95% CI, 0.30 to 0.43) in daily cardiovascular mortality, and 0.47% (95% CI, 0.35 to 0.58) in daily respiratory mortality. The corresponding increases in daily mortality for the same change in PM2.5 concentration were 0.68% (95% CI, 0.59 to 0.77), 0.55% (95% CI, 0.45 to 0.66), and 0.74% (95% CI, 0.53 to 0.95). These associations remained significant after adjustment for gaseous pollutants. Associations were stronger in locations with lower annual mean PM concentrations and higher annual mean temperatures. The pooled concentration-response curves showed a consistent increase in daily mortality with increasing PM concentration, with steeper slopes at lower PM concentrations. CONCLUSIONS: Our data show independent associations between short-term exposure to PM10 and PM2.5 and daily all-cause, cardiovascular, and respiratory mortality in more than 600 cities across the globe. These data reinforce the evidence of a link between mortality and PM concentration established in regional and local studies. (Funded by the National Natural Science Foundation of China and others.).


Assuntos
Poluição do Ar/efeitos adversos , Exposição Ambiental/análise , Mortalidade , Material Particulado/efeitos adversos , Poluição do Ar/análise , Doenças Cardiovasculares/mortalidade , Causas de Morte , Exposição Ambiental/efeitos adversos , Exposição Ambiental/legislação & jurisprudência , Saúde Global , Humanos , Tamanho da Partícula , Material Particulado/análise , Doenças Respiratórias/mortalidade , Risco
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Pharm Res ; 36(11): 152, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31463609

RESUMO

PURPOSE: To develop an analytical platform for the estimation as well as characterization of aggregates over the complete size spectrum (from invisible monomer to visible precipitates). METHODS: Two mAb samples were incubated at 30°C in different buffer systems of protein A chromatography for observing degradation due to aggregation. The aggregation in these samples was quantified by size exclusion chromatography (SEC), dynamic light scattering (DLS), and micro flow imaging (MFI). RESULTS: The results obtained from various characterization tools were analysed in various size ranges - size exclusion chromatography (SEC) (1 nm - 25 nm), dynamic light scattering (DLS) (10 nm - 5 µm), and micro flow imaging (MFI) (2 µm - 300 µm). Since each characterization tool covers a particular size range, data from multiple tools was collected in the "handover" regions to demonstrate accuracy of the platform. CONCLUSIONS: Based on the observations from the experiments, an analytical platform has been proposed covering the whole size spectrum that would be of utility to those engaged in formulation development as well as other aspects related to stability of biotherapeutic products.


Assuntos
Anticorpos Monoclonais/análise , Tampões (Química) , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Difusão Dinâmica da Luz , Nanopartículas/química , Tamanho da Partícula , Multimerização Proteica , Estabilidade Proteica
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