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1.
Bioinformatics ; 40(1)2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38134424

RESUMO

MOTIVATION: Drug-target interaction (DTI) prediction is a relevant but challenging task in the drug repurposing field. In-silico approaches have drawn particular attention as they can reduce associated costs and time commitment of traditional methodologies. Yet, current state-of-the-art methods present several limitations: existing DTI prediction approaches are computationally expensive, thereby hindering the ability to use large networks and exploit available datasets and, the generalization to unseen datasets of DTI prediction methods remains unexplored, which could potentially improve the development processes of DTI inferring approaches in terms of accuracy and robustness. RESULTS: In this work, we introduce GeNNius (Graph Embedding Neural Network Interaction Uncovering System), a Graph Neural Network (GNN)-based method that outperforms state-of-the-art models in terms of both accuracy and time efficiency across a variety of datasets. We also demonstrated its prediction power to uncover new interactions by evaluating not previously known DTIs for each dataset. We further assessed the generalization capability of GeNNius by training and testing it on different datasets, showing that this framework can potentially improve the DTI prediction task by training on large datasets and testing on smaller ones. Finally, we investigated qualitatively the embeddings generated by GeNNius, revealing that the GNN encoder maintains biological information after the graph convolutions while diffusing this information through nodes, eventually distinguishing protein families in the node embedding space. AVAILABILITY AND IMPLEMENTATION: GeNNius code is available at https://github.com/ubioinformat/GeNNius.


Assuntos
Sistemas de Liberação de Medicamentos , Reposicionamento de Medicamentos , Interações Medicamentosas , Difusão , Redes Neurais de Computação
2.
J Sci Food Agric ; 104(6): 3487-3497, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38133882

RESUMO

BACKGROUND: Some environmental enrichment methods, such as occupational enrichment (OE), can improve fish growth, but little is known about its effects on fillet quality. In this study, we evaluated the effects of OE using underwater currents on different aspects of fillet quality and muscle metabolism in rainbow trout (Oncorhynchus mykiss), before and after a handling procedure (fasting). The trout were placed in groups of 30 in separate tanks in three treatments for 30 days: no artificial currents (CON), randomly fired underwater currents (RFC), and continuous underwater currents (CUC). Additionally, half of the individuals in each treatment were fasted (5 days, 45.2 °C days). RESULTS: Slaughter weight, condition factor, and relative growth were lower in CON fish, indicating a positive effect of OE on growth. Rigor mortis, muscle pH, and muscle glycogen levels were similar among treatments, indicating no effect of OE on classical measures of fillet quality. However, significant differences were found regarding fillet colour and muscle enzymes. The fillets of RFC fish were more salmon-pink in colour, which is favoured by consumers. Also, activity levels of pyruvate kinase and glycogen phosphorylase in muscle were significantly higher in CUC fish, probably due to increased energy demands, as pumps were on continually in that treatment. CONCLUSION: Overall, RFC fish seemed to have received enough stimulation to improve growth while not being excessive in terms of exhausting the animals (avoiding negative effects on muscle metabolism), whereas OE may have provided a hormetic effect, allowing fish to better adjust to fasting. © 2023 Society of Chemical Industry.


Assuntos
Oncorhynchus mykiss , Animais , Oncorhynchus mykiss/metabolismo , Alimentos Marinhos/análise , Rigor Mortis
3.
Fish Physiol Biochem ; 50(2): 463-475, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38060080

RESUMO

This study investigated the effects of occupational enrichment, specifically underwater currents, on the stress status of rainbow trout (Oncorhynchus mykiss). A total of 540 fish were divided into three groups: control tanks without artificial currents (CO), tanks with randomly fired underwater currents (RFC), and tanks with continuous current throughout the day (CT). After 30 days, half of the fish in each group underwent a 5-day pre-slaughter fasting (5D), while the others were fed until the day before slaughter (0D). Fish in the RFC group exhibited lower levels of plasma cortisol and acetylcholinesterase enzyme activity in hypothalamus and optic tract than other groups, suggesting an improved stress status. RFC group also showed higher levels of non-esterified fatty acids (NEFA) in 5D fish and higher liver glycogen stores, suggesting improved energy reserves. In comparison, the CT group had higher LDH levels, possibly due to their increased swimming activity. The CO group had significantly lower NEFA levels at 5D compared to the RFC group, suggesting lower energy reserves. The RFC fish had darker and yellow-reddish skin and liver color, suggesting an improved stress status and lower lipid reserves, respectively. Overall, although a significant stress response was not observed in fasted individuals, possibly due to the relatively short fasting period, the study suggests that providing occupational enrichment using randomly fired underwater currents for 1 month helped to improve stress status in rainbow trout, indicating that occupational enrichment during the grow-out phase can positively impact the welfare of rainbow trout during routine handling procedures.


Assuntos
Oncorhynchus mykiss , Animais , Oncorhynchus mykiss/fisiologia , Ácidos Graxos não Esterificados/farmacologia , Acetilcolinesterase , Fígado , Jejum/fisiologia
4.
Bioconjug Chem ; 34(12): 2275-2292, 2023 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-37882455

RESUMO

Oriented and covalent immobilization of proteins on magnetic nanoparticles (MNPs) is particularly challenging as it requires both the functionality of the protein and the colloidal stability of the MNPs to be preserved. Here, we describe a simple, straightforward, and efficient strategy for MNP functionalization with proteins using metal affinity binding. Our method involves a single-step process where MNPs are functionalized using a preformed, ready-to-use nitrilotriacetic acid-divalent metal cation (NTA-M2+) complex and polyethylene glycol (PEG) molecules. As a proof-of-concept, we demonstrate the oriented immobilization of a recombinant cadherin fragment engineered with a hexahistidine tag (6His-tag) onto the MNPs. Our developed methodology is simple and direct, enabling the oriented bioconjugation of His-tagged cadherins to MNPs while preserving protein functionality and the colloidal stability of the MNPs, and could be extended to other proteins expressing a polyhistidine tag. When compared to the traditional method where NTA is first conjugated to the MNPs and afterward free metal ions are added to form the complex, this novel strategy results in a higher functionalization efficiency while avoiding MNP aggregation. Additionally, our method allows for covalent bonding of the cadherin fragments to the MNP surface while preserving functionality, making it highly versatile. Finally, our strategy not only ensures the correct orientation of the protein fragments on the MNPs but also allows for the precise control of their density. This feature enables the selective targeting of E-cadherin-expressing cells only when MNPs are decorated with a high density of cadherin fragments.


Assuntos
Nanopartículas de Magnetita , Nanopartículas de Magnetita/química , Indicadores e Reagentes , Quelantes , Ácido Nitrilotriacético/química , Caderinas/química , Metais
5.
Br J Cancer ; 126(3): 331-350, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34811504

RESUMO

Prostate cancer is a global cancer burden and considerable effort has been made through the years to identify biomarkers for the disease. Approximately a decade ago, the potential of analysing extracellular vesicles in liquid biopsies started to be envisaged. This was the beginning of a new exciting area of research investigating the rich molecular treasure found in extracellular vesicles to identify biomarkers for a variety of diseases. Vesicles released from prostate cancer cells and cells of the tumour microenvironment carry molecular information about the disease that can be analysed in several biological fluids. Numerous studies document the interest of researchers in this field of research. However, methodological issues such as the isolation of vesicles have been challenging. Remarkably, novel technologies, including those based on nanotechnology, show promise for the further development and clinical use of extracellular vesicles as liquid biomarkers. Development of biomarkers is a long and complicated process, and there are still not many biomarkers based on extracellular vesicles in clinical use. However, the knowledge acquired during the last decade constitutes a solid basis for the future development of liquid biopsy tests for prostate cancer. These are urgently needed to bring prostate cancer treatment to the next level in precision medicine.


Assuntos
Biomarcadores Tumorais/análise , Ácidos Nucleicos Livres/análise , Detecção Precoce de Câncer/métodos , Vesículas Extracelulares/metabolismo , Biópsia Líquida/métodos , Células Neoplásicas Circulantes/patologia , Neoplasias da Próstata/diagnóstico , Animais , Ácidos Nucleicos Livres/genética , Ácidos Nucleicos Livres/metabolismo , Vesículas Extracelulares/genética , Humanos , Masculino , Medicina de Precisão , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo
6.
Bioconjug Chem ; 33(9): 1620-1633, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-35857350

RESUMO

In this work, we report the use of bioorthogonal chemistry, specifically the strain-promoted click azide-alkyne cycloaddition (SPAAC) for the covalent attachment of magnetic nanoparticles (MNPs) on living cell membranes. Four types of MNPs were prepared, functionalized with two different stabilizing/passivation agents (a polyethylene glycol derivative and a glucopyranoside derivative, respectively) and two types of strained alkynes with different reactivities: a cyclooctyne (CO) derivative and a dibenzocyclooctyne (DBCO) derivative. The MNPs were extensively characterized in terms of physicochemical characteristics, colloidal stability, and click reactivity in suspension. Then, the reactivity of the MNPs toward azide-modified surfaces was evaluated as a closer approach to their final application in a living cell scenario. Finally, the DBCO-modified MNPs, showing superior reactivity in suspension and on surfaces, were selected for cell membrane immobilization via the SPAAC reaction on the membranes of cells engineered to express azide artificial reporters. Overall, our work provides useful insights into the appropriate surface engineering of nanoparticles to ensure a high performance in terms of bioorthogonal reactivity for biological applications.


Assuntos
Azidas , Nanopartículas de Magnetita , Alcinos/química , Azidas/química , Membrana Celular , Química Click , Reação de Cicloadição , Polietilenoglicóis/química
7.
Nano Lett ; 21(17): 7213-7220, 2021 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-34410726

RESUMO

The contactless heating capacity of magnetic nanoparticles (MNPs) has been exploited in fields such as hyperthermia cancer therapy, catalysis, and enzymatic thermal regulation. Herein, we propose an advanced technology to generate multiple local temperatures in a single-pot reactor by exploiting the unique nanoheating features of iron oxide MNPs exposed to alternating magnetic fields (AMFs). The heating power of the MNPs depends on their magnetic features but also on the intensity and frequency conditions of the AMF. Using a mixture of diluted colloids of MNPs we were able to generate a multi-hot-spot reactor in which each population of MNPs can be selectively activated by adjusting the AMF conditions. The maximum temperature reached at the surface of each MNP was registered using independent fluorescent thermometers that mimic the molecular link between enzymes and MNPs. This technology paves the path for the implementation of a selective regulation of multienzymatic reactions.


Assuntos
Hipertermia Induzida , Nanopartículas de Magnetita , Nanopartículas , Campos Magnéticos , Nanopartículas Magnéticas de Óxido de Ferro , Magnetismo
8.
Int J Mol Sci ; 23(23)2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36499587

RESUMO

SARS-CoV-2, a positive-strand RNA virus has caused devastating effects. The standard method for COVID diagnosis is based on polymerase chain reaction (PCR). The method needs expensive reagents and equipment and well-trained personnel and takes a few hours to be completed. The search for faster solutions has led to the development of immunological assays based on antibodies that recognize the viral proteins that are faster and do not require any special equipment. Here, we explore an innovative analytical approach based on the sandwich oligonucleotide hybridization which can be adapted to several biosensing devices including thermal lateral flow and electrochemical devices, as well as fluorescent microarrays. Polypurine reverse-Hoogsteen hairpins (PPRHs) oligonucleotides that form high-affinity triplexes with the polypyrimidine target sequences are used for the efficient capture of the viral genome. Then, a second labeled oligonucleotide is used to detect the formation of a trimolecular complex in a similar way to antigen tests. The reached limit of detection is around 0.01 nM (a few femtomoles) without the use of any amplification steps. The triplex enhanced nucleic acid detection assay (TENADA) can be readily adapted for the detection of any pathogen requiring only the knowledge of the pathogen genome sequence.


Assuntos
COVID-19 , Ácidos Nucleicos , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Oligonucleotídeos/química , Reação em Cadeia da Polimerase , RNA Viral/genética , RNA Viral/análise , Técnicas de Amplificação de Ácido Nucleico/métodos
9.
J Obstet Gynaecol ; 42(7): 3397-3399, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35658728

RESUMO

This brief report evaluates the early effect of ultra-low dose 0.005% oestriol vaginal gel on dyspareunia in postmenopausal women within the first 2 weeks of treatment. This was a prospective and multicentre single-arm pilot study and the effect of the treatment on dyspareunia was evaluated by using a diary. In total 23 women and 150 coitus were studied. 8 coitus were painless in the first week and 42 during the second week (p < .0001). A reduction in pain from the baseline was seen in 116 (77.3%) out of the 150 coitus. 0.005% oestriol vaginal gel produced a rapid and progressive improvement in dyspareunia from the very first days of treatment in postmenopausal women.IMPACT STATEMENTWhat is already known on this subject? Local oestrogen therapy has shown efficacy in the treatment of genitourinary syndrome of menopause (GSM) and dyspareunia when used for a duration of greater than 3 weeks.What do the results of this study add? This study shows that the use of oestriol gel produces clinical effects from the beginning of its use, decreasing dyspareunia in postmenopausal women within just 14 days of daily use.What are the implications of these findings for clinical practice and/or further research? In cases of dyspareunia in relation to menopause, therapy with local oestrogens, in our case oestriol gel, produces an improvement from the beginning of its use. This information is clinically relevant when evaluating therapeutic options.


Assuntos
Dispareunia , Doenças Vaginais , Feminino , Humanos , Dispareunia/tratamento farmacológico , Dispareunia/etiologia , Pós-Menopausa , Projetos Piloto , Doenças Vaginais/terapia , Vagina , Estudos Prospectivos , Cremes, Espumas e Géis Vaginais , Estriol
10.
Inorg Chem ; 60(1): 152-160, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33201695

RESUMO

We describe a wet chemical method for the synthesis of uniform and well-dispersed dysprosium vanadate (DyVO4) and holmium vanadate (HoVO4) nanoparticles with an almost spherical shape and a mean size of ∼60 nm and their functionalization with poly(acrylic acid). The transverse magnetic relaxivity of both systems at 9.4 T is analyzed on the basis of magnetic susceptibility and magnetization measurements in order to evaluate their potential for application as high-field MRI contrast agents. In addition, the X-ray attenuation properties of these systems are also studied to determine their capabilities as computed tomography contrast agent. Finally, the colloidal stability under physiological pH conditions and the cytotoxicity of the functionalized NPs are also addressed to assess their suitability for bioimaging applications.


Assuntos
Meios de Contraste/química , Disprósio/química , Hólmio/química , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Vanadatos/química , Resinas Acrílicas/química , Sobrevivência Celular/efeitos dos fármacos , Meios de Contraste/farmacologia , Disprósio/farmacologia , Hólmio/farmacologia , Humanos , Campos Magnéticos , Nanopartículas/química , Células PC-3 , Tamanho da Partícula , Vanadatos/farmacologia
11.
J Nanobiotechnology ; 19(1): 54, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33627152

RESUMO

BACKGROUND: Gene and chemical therapy has become one of the rising stars in the field of molecular medicine during the last two decades. However, there are still numerous challenges in the development of efficient, targeted, and safe delivery systems that can avoid siRNA degradation and reduce the toxicity and adverse effects of chemotherapy medicine. RESULTS: In this paper, a highly efficient AS1411 aptamer modified, dsDNA and MMP-2 cleavable peptide-fabricated gold nanocage vehicle, which could load doxorubicin hydrochloride (DOX) and siRNAs to achieve a combination of tumor responsive genetic therapy, chemotherapy, and photothermal treatment is presented. Our results show that this combined treatment achieved targeted gene silencing and tumor inhibition. After nearly one month of treatment with DOX-loaded Au-siRNA-PAA-AS1411 nanoparticles with one dose every three days in mice, a synergistic effect promoting the eradication of long-lived tumors was observed along with an increased survival rate of mice. The combined genetic, chemotherapeutic, and photothermal treatment group exhibited more than 90% tumor inhibition ratio (tumor signal) and a ~ 67% survival rate compared with a 30% tumor inhibition ratio and a 0% survival rate in the passive genetic treatment group. CONCLUSIONS: The development of nanocarriers with double-stranded DNA and MMP-2 cleavable peptides provides a new strategy for the combined delivery of gene and chemotherapy medicine. Au-siRNA-PAA-AS1411 exerts high anticancer activities on lung cancer, indicating immense potentials for clinical application.


Assuntos
Técnicas de Transferência de Genes , Ouro/química , Ouro/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas Metálicas/química , RNA Interferente Pequeno/farmacologia , Animais , Aptâmeros de Nucleotídeos , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Portadores de Fármacos , Sistemas de Liberação de Medicamentos/métodos , Pulmão , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Oligodesoxirribonucleotídeos , Tamanho da Partícula , Taxa de Sobrevida
12.
J Low Genit Tract Dis ; 25(2): 130-136, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33746195

RESUMO

OBJECTIVE: The aim of the study was to evaluate the efficacy of Papilocare, a Coriolus versicolor-based vaginal gel, in repairing human papillomavirus (HPV)-related low-grade cervical lesions. METHODS: The study is a multicenter, open-label, randomized, parallel-group, watchful waiting approach-controlled trial involving 91 HPV-positive women with low-grade Pap smear alterations and consistent colposcopy. RESULTS: The percentage of patients with normal Pap smear and concordant colposcopy 3 and 6 months after receiving treatment (78.0% and 84.9%) was significantly higher than without treatment (54.8% and 64.5%), especially in high-risk HPV patients (79.5% and 87.8% vs 52.0% and 56.0%). At 6-month visit, overall HPV clearance was achieved by a greater number of patients receiving treatment (59.6%) compared with those without treatment (41.9%), especially high-risk HPV ones (62.5% vs 40.0%). The cervical re-epithelization score was significantly higher with treatment (mean = 4.5) than without (mean = 4.1). Compared with baseline, perceived stress decreased in the treatment group (from 21.1 to 19.0) and increased in the control group (from 17.7 to 20.7). A total of 7 possible or probable treatment-related adverse events were reported, most of them (n = 6) being mild or moderate in severity. CONCLUSIONS: Treatment with Papilocare has demonstrated a better clinical benefit than the conventional watchful waiting approach in clinical practice for total and high-risk HPV patients in terms of its efficacy to treat HPV-related cervical lesions and to clear all HPV strains after a single 6-month period. It has demonstrated an adequate safety and tolerability and confers additional benefits such as higher re-epithelization, stress reduction, and high treatment adherence.


Assuntos
Papillomaviridae/efeitos dos fármacos , Infecções por Papillomavirus/tratamento farmacológico , Polyporaceae , Displasia do Colo do Útero/tratamento farmacológico , Displasia do Colo do Útero/virologia , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/virologia , Cremes, Espumas e Géis Vaginais/farmacologia , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Espanha , Resultado do Tratamento , Neoplasias do Colo do Útero/patologia , Adulto Jovem , Displasia do Colo do Útero/patologia
13.
Angew Chem Int Ed Engl ; 60(7): 3449-3453, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33283392

RESUMO

The ring-opening polymerisation of α-amino acid N-carboxyanhydrides (NCAs) offers a simple and scalable route to polypeptides with predicted and narrow molecular weight distributions. Here we show how polyoxometalates (POMs)-redox-active molecular metal-oxide anions-can serve as inorganic scaffold initiators for such NCA polymerisations. This "On-POM polymerisation" strategy serves as an innovative platform to design hybrid materials with additive or synergistic properties stemming from the inorganic and polypeptide component parts. We have used this synthetic approach to synthesise a library of bactericidal poly(lysine)-POM hybrid derivatives that can be used to prevent biofilm formation. This versatile "On-POM polymerisation" method provides a flexible synthetic approach for combining inorganic scaffolds with amino acids, and the potential to tailor and improve the specificity and performance of hybrid antimicrobial materials.

14.
Small ; 16(36): e2003303, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32700469

RESUMO

Nanotechnologies have reached maturity and market penetration that require nano-specific changes in legislation and harmonization among legislation domains, such as the amendments to REACH for nanomaterials (NMs) which came into force in 2020. Thus, an assessment of the components and regulatory boundaries of NMs risk governance is timely, alongside related methods and tools, as part of the global efforts to optimise nanosafety and integrate it into product design processes, via Safe(r)-by-Design (SbD) concepts. This paper provides an overview of the state-of-the-art regarding risk governance of NMs and lays out the theoretical basis for the development and implementation of an effective, trustworthy and transparent risk governance framework for NMs. The proposed framework enables continuous integration of the evolving state of the science, leverages best practice from contiguous disciplines and facilitates responsive re-thinking of nanosafety governance to meet future needs. To achieve and operationalise such framework, a science-based Risk Governance Council (RGC) for NMs is being developed. The framework will provide a toolkit for independent NMs' risk governance and integrates needs and views of stakeholders. An extension of this framework to relevant advanced materials and emerging technologies is also envisaged, in view of future foundations of risk research in Europe and globally.


Assuntos
Nanoestruturas , Nanotecnologia , Medição de Risco , Nanoestruturas/toxicidade , Nanotecnologia/normas , Nanotecnologia/tendências , Medição de Risco/normas
15.
Nanotechnology ; 30(11): 112001, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30609414

RESUMO

Magnetic nanoparticles (MNPs), and in particular iron oxide nanoparticles (mainly magnetite and maghemite), are being widely used in the form of aqueous colloids for biomedical applications. In such colloids, nanoparticles tend to form assemblies, either aggregates, if the union is permanent, or agglomerates, if it is reversible. These clustering processes have a strong impact on the MNPs' properties that are often not well understood. In this review, the causes and consequences of MNPs aggregation/agglomeration are reviewed and discussed. Special attention has been paid to the impact of the MNPs aggregation/agglomeration on their magnetic properties and heating properties, when exposed to an alternating magnetic field in the frame of magnetic hyperthermia. In addition, a model system with MNPs of two different sizes coated with three different molecules oleic acid, meso-2, 3-dimercaptosuccinic acid and poly(maleic anhydride-alt-1-octadecene) has been characterized and the results used to support the ideas reviewed.

16.
Anal Bioanal Chem ; 411(9): 1873-1885, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30155701

RESUMO

Here we describe a simple approach for the simultaneous detection of multiple microRNAs (miRNAs) using a single nanostructured reagent as surface plasmon resonance imaging (SPRi) enhancer and without using enzymatic reactions, sequence specific enhancers or multiple enhancing steps as normally reported in similar studies. The strategy involves the preparation and optimisation of neutravidin-coated gold nanospheres (nGNSs) functionalised with a previously biotinylated antibody (Ab) against DNA/RNA hybrids. The Ab guarantees the recognition of any miRNA sequence adsorbed on a surface properly functionalised with different DNA probes; at the same time, gold nanoparticles permit to detect this interaction, thus producing enough SPRi signal even at a low ligand concentration. After a careful optimisation of the nanoenhancer and after its characterisation, the final assay allowed the simultaneous detection of four miRNAs with a limit of detection (LOD) of up to 0.5 pM (equal to 275 attomoles in 500 µL) by performing a single enhancing injection. The proposed strategy shows good signal specificity and permits to discriminate wild-type, single- and triple-mutated sequences much better than non-enhanced SPRi. Finally, the method works properly in complex samples (total RNA extracted from blood) as demonstrated by the detection of four miRNAs potentially related to multiple sclerosis used as case study. This proof-of-concept study confirms that the approach provides the possibility to detect a theoretically unlimited number of miRNAs using a simple protocol and an easily prepared enhancing reagent, and may further facilitate the development of affordable multiplexing miRNA screening for clinical purposes.


Assuntos
MicroRNAs/análise , Ressonância de Plasmônio de Superfície/métodos , Adsorção , DNA/química , Enzimas/química , Indicadores e Reagentes/química , Dispositivos Lab-On-A-Chip , Ligantes , Limite de Detecção , MicroRNAs/química , Microscopia Eletrônica de Varredura , Hibridização de Ácido Nucleico , Estudo de Prova de Conceito , Propriedades de Superfície
17.
J Nanobiotechnology ; 17(1): 15, 2019 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-30683129

RESUMO

BACKGROUND: Infectious diseases are still a leading cause of death and, with the emergence of drug resistance, pose a great threat to human health. New drugs and strategies are thus urgently needed to improve treatment efficacy and limit drug-associated side effects. Nanotechnology-based drug delivery systems are promising approaches, offering hope in the fight against drug resistant bacteria. However, how nanocarriers influence the response of innate immune cells to bacterial infection is mostly unknown. RESULTS: Here, we used Mycobacterium tuberculosis as a model of bacterial infection to examine the impact of mannose functionalization of chitosan nanocarriers (CS-NCs) on the human macrophage response. Both ungrafted and grafted CS-NCs were similarly internalized by macrophages, via an actin cytoskeleton-dependent process. Although tri-mannose ligands did not modify the capacity of CS-NCs to escape lysosomal degradation, they profoundly remodeled the response of M. tuberculosis-infected macrophages. mRNA sequencing showed nearly 900 genes to be differentially expressed due to tri-mannose grafting. Unexpectedly, the set of modulated genes was enriched for pathways involved in cell metabolism, particularly oxidative phosphorylation and sugar metabolism. CONCLUSIONS: The ability to modulate cell metabolism by grafting ligands at the surface of nanoparticles may thus be a promising strategy to reprogram immune cells and improve the efficacy of encapsulated drugs.


Assuntos
Infecções Bacterianas/imunologia , Quitosana/química , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Imunidade Inata/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Manose/química , Infecções Bacterianas/microbiologia , Células Cultivadas , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Macrófagos/metabolismo , Macrófagos/microbiologia , Redes e Vias Metabólicas/efeitos dos fármacos , Mycobacterium tuberculosis/fisiologia , Nanopartículas/química , Nanopartículas/metabolismo , Fagocitose , Transcriptoma/efeitos dos fármacos
18.
Molecules ; 24(14)2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31311176

RESUMO

Natural polysaccharides are frequently used in the design of drug delivery systems due to their biocompatibility, biodegradability, and low toxicity. Moreover, they are diverse in structure, size, and charge, and their chemical functional groups can be easily modified to match the needs of the final application and mode of administration. This review focuses on polysaccharidic nanocarriers based on chitosan and hyaluronic acid for small interfering RNA (siRNA) delivery, which are highly positively and negatively charged, respectively. The key properties, strengths, and drawbacks of each polysaccharide are discussed. In addition, their use as efficient nanodelivery systems for gene silencing applications is put into context using the most recent examples from the literature. The latest advances in this field illustrate effectively how chitosan and hyaluronic acid can be modified or associated with other molecules in order to overcome their limitations to produce optimized siRNA delivery systems with promising in vitro and in vivo results.


Assuntos
Quitosana/química , Ácido Hialurônico/química , Polissacarídeos/química , RNA Interferente Pequeno/administração & dosagem , Produtos Biológicos/química , Sistemas de Liberação de Medicamentos , Inativação Gênica , Humanos , Estrutura Molecular , Nanopartículas , RNA Interferente Pequeno/química
19.
Fish Physiol Biochem ; 45(1): 253-265, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30140961

RESUMO

Fish normally undergo periods of food deprivation that are longer than non-hibernating mammals. In aquacultured rainbow trout (Oncorhynchus mykiss), it is unclear how fasting may affect their physiological adaptative response, especially when they are normally fed daily. In addition, that response may vary with temperature, making it necessary to express fasting duration in terms of degree days. In the current study, trout were fasted for 5, 10, and 20 days (55, 107, and 200 degree days (°C d), respectively). To assess the physiological response of fish to fasting, different biometric, blood, plasma, and metabolic parameters were measured, as well as liver fatty acid composition. The fish weight, condition factor, and the hepato-somatic index of 5-day fasted trout were not significantly different from those of control fish. Gastric pH increased as fasting progressed while plasma concentrations of glucose, triglycerides, and total proteins decreased significantly after 10 days of fasting, while the percentage of non-esterified fatty acids increased. There were no significant differences in plasma ions (sodium, potassium, and calcium), except for chloride ion which decreased after 5 days of fasting. Liver glycogen decreased after 5 days of fasting while glycogen concentration in muscle did not decrease until 20 days of fasting. Liver color presented a higher chroma after 5 days of fasting, suggesting a mobilization of reserves. Finally, acetylcholinesterase activity in the brain was not affected by food deprivation but increased after 10 days of fasting in liver and muscle, suggesting the mobilization of body reserves, but without severely affecting basal metabolism.


Assuntos
Privação de Alimentos , Oncorhynchus mykiss/fisiologia , Estresse Fisiológico , Animais , Conteúdo Gastrointestinal , Concentração de Íons de Hidrogênio , Estômago/fisiologia
20.
J Nanobiotechnology ; 16(1): 33, 2018 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-29602307

RESUMO

BACKGROUND: Dynein is a cytoskeletal molecular motor protein that transports cellular cargoes along microtubules. Biomimetic synthetic peptides designed to bind dynein have been shown to acquire dynamic properties such as cell accumulation and active intra- and inter-cellular motion through cell-to-cell contacts and projections to distant cells. On the basis of these properties dynein-binding peptides could be used to functionalize nanoparticles for drug delivery applications. RESULTS: Here, we show that gold nanoparticles modified with dynein-binding delivery sequences become mobile, powered by molecular motor proteins. Modified nanoparticles showed dynamic properties, such as travelling the cytosol, crossing intracellular barriers and shuttling the nuclear membrane. Furthermore, nanoparticles were transported from one cell to another through cell-to-cell contacts and quickly spread to distant cells through cell projections. CONCLUSIONS: The capacity of these motor-bound nanoparticles to spread to many cells and increasing cellular retention, thus avoiding losses and allowing lower dosage, could make them candidate carriers for drug delivery.


Assuntos
Sistemas de Liberação de Medicamentos , Dineínas/metabolismo , Nanopartículas Metálicas/química , Nanotecnologia/métodos , Sequência de Aminoácidos , Animais , Linhagem Celular , Ouro/química , Humanos , Nanopartículas Metálicas/ultraestrutura , Microtúbulos/metabolismo , Peso Molecular , Membrana Nuclear/metabolismo , Peptídeos/química , Peptídeos/metabolismo , Ligação Proteica
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