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1.
Sci Rep ; 8(1): 10900, 2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-30006608

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

2.
Sci Rep ; 7(1): 13036, 2017 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-29026207

RESUMO

The repeated use of conventional synthetic pesticides in crop protection leads to resistance development by pests along with a negative impact on the environment, particularly non-target arthropods. Plant-derived active compounds, such as essential oils (EOs), play a key role in sustainably controlling pests. The lethal and sublethal activity of citrus peel EOs as emulsions and included in polyethylene glycol (PEG) nanoparticles (EO-NPs) was determined against the invasive tomato pest Tuta absoluta. Their effects on the plants were also assessed. The results showed an overall good insecticidal activity of the compounds tested, with a higher mortality through contact on eggs and larvae by EO emulsions and through ingestion on larvae by EO-NPs. The nanoformulation also significantly reduced the visible toxic effects on the plants. The data collected suggest that these natural compounds, especially when nanoformulated, could be successfully used in integrated pest management programs for T. absoluta.


Assuntos
Citrus/química , Composição de Medicamentos , Lepidópteros/efeitos dos fármacos , Nanopartículas/química , Óleos Voláteis/farmacologia , Controle Biológico de Vetores , Solanum lycopersicum/parasitologia , Animais , Bioensaio , Larva/efeitos dos fármacos , Óleos Voláteis/toxicidade , Tamanho da Partícula
3.
J Colloid Interface Sci ; 506: 532-542, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-28756320

RESUMO

The actual surface termination and lateral size of a nanomaterial is crucial in its interaction with biomolecules at the aqueous interface. Graphene oxide (GO) nanosheets have been demonstrated as promising nanoplatform for both diagnostic and therapeutic applications. To this respect, 'smart' GO nanocarriers have been obtained by the surface functionalisation with polymers sensitive, e.g., to pH, as the polyacrylate (PAA) case. In this work, hybrid GO/PAA samples prepared respectively at low (GOPAAthin) or high (GOPAAthick) monomer grafting ratio, were scrutinised both theoretically, by molecular dynamic calculations, and experimentally by a multitechnique approach, including spectroscopic (UV-visible, fluorescence, Raman, Attenuated-total reflectance-Fourier transformed infrared and X-ray photoelectron spectroscopies), spectrometric (time-of-flight secondary ion and electrospray ionisation mass spectrometries) and microscopic (atomic force and confocal microscopies) methods. The actual surface termination, evaluated in terms of the relative ratio between polar and dispersive groups at the surface of the GO/polymer systems, was found to correlate with the average orientation of hydrophilic/hydrophobic domains of albumin, used as model protein. Moreover, the comparison among GO, GO-PAAthin and GO-PAAthick in the optical response at the interface with aqueous solutions, both at acid and at physiological pH, showed that the hybrid GO-polymer platform could be suitable not only to exploit a pH-triggered drug release but also for a modulation of the GO intrinsic emission properties. Energy transfer experiments on the GO/polymer oxide/fluorescein-labelled albumin/doxorubicin assembly showed significant differences for GO and GO-PAA samples, thus demonstrating the occurrence of different electronic processes at the hybrid nano-bio-interfaces. Confocal microscopy studies of cellular uptake in neuroblastoma cells confirmed the promising potentialities of the developed nanoplatform for applications at the biointerface.


Assuntos
Resinas Acrílicas/química , Portadores de Fármacos/química , Grafite/química , Nanoestruturas/química , Óxidos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Fluoresceína/química , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Polimerização , Propriedades de Superfície
4.
ACS Omega ; 2(8): 4071-4079, 2017 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31457708

RESUMO

Neurotrophins are essential proteins for the development and maintenance of neural functions as well as promising drugs in neurodegenerative disorders. Current limits in their effective clinical applications can be overwhelmed by the combined use of peptidomimetic and nanomedicine approaches. Indeed, neurotrophin-mimicking peptides may allow minimizing the adverse side effects of the whole protein drug. Moreover, the immobilization of such peptides on nanomaterials may offer additional advantages, including protection against degradation, enhanced permeability of barrier membranes, and intrinsic therapeutic properties of the nanoparticles (e.g., antiangiogenic and plasmonic features of gold nanoparticles (AuNPs)). In the present article, we scrutinize the functionalization of spherical AuNPs of diameter 12 nm by peptides because of the N-terminal domains of the nerve growth factor (NGF) and the brain-derived neurotrophic factor (BDNF), NGF1-14 and BDNF1-12, respectively. The hybrid gold-peptide nanobiointerface was investigated, both in the direct physisorption and in the lipid-bilayer-mediated adsorption processes, by a multitechnique study that included UV-vis and X-ray photoelectron spectroscopies, dynamic light scattering, zeta-potential analyses, and atomic force microscopy. Both peptide- and lipid-dependent features were identified, to have a modulation in the peptide coverage of nanoparticles as well as in the cellular uptake of NGF and BDNF peptides, as investigated by confocal microscopy. The promising potentials of the neurotrophins to cross the blood-brain barrier were demonstrated.

5.
Eur J Med Chem ; 57: 149-61, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23047231

RESUMO

Newly synthesized sulfonilamidothiopyrimidone derivatives and a subset of 14 sulfonilamidothiopyrimidones and thiopyrimidones selected by an MTT assays cell viability guided selection from an in house collection were evaluated to determine the inhibitory effect on the PGE(2) formation in human peripheral blood lymphocytes (PBLs) using commercial ELISA. The newly synthesized sulfonilamidothiopyrimidone derivatives showed interesting pharmacological activities. Preliminary in vitro assays showed that compounds 2-5 are endowed with very high activity. Compound 2 was the most active as hCOX-2 inhibitor. The observed effects were not due to an inhibition of cell proliferation as proved by the BrdU assay. Western blot of COX-2 confirmed the inhibition on the PGE(2) secretion. Further evidence on the inhibitory potential and selectivity as COX-2 inhibitors of the selected compounds came from the in vitro screening. In order to better rationalize the action and the binding mode of these compounds, docking studies were carried out. These studies were in agreement with the biological data. Compounds 2-5 were able to fit into the active site of COX-2 with highest scores and interaction energies. Furthermore, compound 2, which showed an inhibition of around 50% on PGE(2) production, was the best scored in all the docking calculations carried out.


Assuntos
Inibidores de Ciclo-Oxigenase 2/síntese química , Ciclo-Oxigenase 2/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Pirimidinonas/síntese química , Sulfonamidas/síntese química , Tiadiazóis/síntese química , Western Blotting , Bromodesoxiuridina , Domínio Catalítico , Morte Celular/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase 2/farmacologia , Dinoprostona/antagonistas & inibidores , Dinoprostona/biossíntese , Humanos , Interleucina-2/farmacologia , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Simulação de Acoplamento Molecular , Pirimidinonas/farmacologia , Relação Estrutura-Atividade , Sulfonamidas/farmacologia , Termodinâmica , Tiadiazóis/farmacologia
6.
Vet Res Commun ; 35(8): 521-30, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21881904

RESUMO

The aim of this study was to provide basal values of phospholipid (PL) composition in different animal species by 31P NMR analysis using detergents. This fast and accurate method allowed a quantitative analysis of PLs without any previous separation. Plasma and erythrocyte membrane PLs were investigated in mammals (pig, cow, horse). Moreover, for the first time, the composition of plasma PLs in avian (chicken and ostrich) was performed by 31P NMR. Significant qualitative and quantitative interspecies differences in plasma PL levels were found. Phosphatidilcholine (PC) and sphingomyelin (SPH) levels were significantly higher (P < 0.001) in chicken plasma than all the other species tested. In erythrocytes, cow PC and phosphatidylcholine diarachidoyl were significantly lower (P < 0.001) than for pigs and horses, whereas pig PC presented intermediate values among cows and horses. Inorganic phosphate and 2,3-diphosphoglycerate levels were also significantly different between the species under investigation. The [SPH/total PLs] molar ratios in erythrocytes confirmed interspecies differences in phospholipid composition while the PC/SPH molar ratios could be related to a distinct erythrocyte flexibility and aggregability. Diet and nutrition may contribute primarily to the interspecies differences in plasma PL amounts detected. Significant differences between chicken plasma PC and SPH levels and those of the other animal species could be ascribed to a fat metabolism specific to egg production.


Assuntos
Membrana Celular/química , Eritrócitos/química , Fosfolipídeos/química , Fósforo/química , Animais , Galinhas , Espectroscopia de Ressonância Magnética , Mamíferos , Especificidade da Espécie , Struthioniformes
7.
Arch Virol ; 156(8): 1371-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21503642

RESUMO

Threatening sporadic outbreaks of avian influenza and the H1N1 pandemic of 2009 highlight the need for rapid and accurate detection and typing of influenza viruses. In this paper, we describe the validation of the VereFlu™ Lab-on-Chip Influenza Assay, which is based on the integration of two technologies: multiplex reverse transcription (RT)-PCR followed by microarray amplicon detection. This assay simultaneously detects five influenza virus subtypes, including the 2009 pandemic influenza A (H1N1), seasonal H1N1, H3N2, H5N1 and influenza B virus. The VereFlu™ assay was clinically validated in Singapore and compared against reference methods of real-time PCR, virus detection by immunofluorescence of cell cultures and sequencing. A sensitivity and specificity of 96.8% and 92.8%, respectively, was demonstrated for pandemic H1N1; 95.7% and 100%, respectively, for seasonal H1N1; 91.2% and 97.6%, respectively, for seasonal H3N2; 95.2% and 100%, respectively, for influenza B. Additional evaluations carried out at the World Health Organization (WHO) Collaborating Centre, Melbourne, Australia, confirmed that the test was able to reliably detect H5N1. This portable, fast time-to-answer (3 hours) device is particularly suited for diagnostic applications of detection, differentiation and identification of human influenza virus subtypes.


Assuntos
Vírus da Influenza A/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Análise Serial de Proteínas/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Humanos , Vírus da Influenza A/classificação , Dispositivos Lab-On-A-Chip , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
Clin Chem Lab Med ; 48(3): 329-36, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20020819

RESUMO

BACKGROUND: Several microdevices have been developed to perform only a single step of a genotyping process, such as PCR or detection by probe hybridization. Here, we describe a Lab-on-Chip (LoC) platform integrating a PCR amplification microreactor with a customable microarray for the detection of sequence variations on human genomic DNA. METHODS: Preliminary work was focused on developing the single analytical steps including PCR and labeling strategies of the amplified product by conventional reference systems. The optimized protocols included a 1:4 forward:reverse primer ratio for asymmetric PCR, and Cy5-dCTP multiple incorporation for the generation of a labeled PCR product to be hybridized to complementary probes bound to the chip surface. RESULTS: Final conditions were applied to the fully integrated LoC platform for the detection of the IVSI-110 G > A mutation in the human beta-globin (HBB) gene associated with beta-thalassemia, used as a model of genetic application, allowing for correct genotyping of 25 samples that were heterozygous, homozygous or wild-type for this mutation. CONCLUSIONS: The overall results show that the present platform is very promising for rapid identification of DNA sequence variations in an integrated, cost effective and convenient silicon chip format.


Assuntos
Dispositivos Lab-On-A-Chip , Técnicas de Diagnóstico Molecular/instrumentação , Reação em Cadeia da Polimerase , Carbocianinas/química , Carbocianinas/metabolismo , Nucleotídeos de Desoxicitosina/química , Nucleotídeos de Desoxicitosina/metabolismo , Variação Genética , Genoma Humano , Genótipo , Humanos , Técnicas de Diagnóstico Molecular/métodos , Análise de Sequência com Séries de Oligonucleotídeos , Talassemia/genética , Globinas beta/genética
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