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1.
Adv Healthc Mater ; : e2400946, 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38736024

RESUMO

Current research in cancer therapy focuses on personalized therapies, through nanotechnology-based targeted drug delivery systems. Particularly, controlled drug release with nanoparticles (NPs) can be designed to safely transport various active agents, optimizing delivery to specific organs and tumors, minimizing side effects. The use of microfluidics (MFs) in this field has stood out against conventional methods by allowing precise control over parameters like size, structure, composition, and mechanical/biological properties of nanoscale carriers. This review compiles applications of microfluidics in the production of core-shell NPs (CSNPs) for cancer therapy, discussing the versatility inherent in various microchannel and/or micromixer setups and showcasing how these setups can be utilized individually or in combination, as well as how this technology allows the development of new advances in more efficient and controlled fabrication of core-shell nanoformulations. Recent biological studies have achieved an effective, safe, and controlled delivery of otherwise unreliable encapsulants such as small interfering RNA (siRNA), plasmid DNA (pDNA), and cisplatin as a result of precisely tuned fabrication of nanocarriers, showing that this technology is paving the way for innovative strategies in cancer therapy nanofabrication, characterized by continuous production and high reproducibility. Finally, this review analyzes the technical, biological, and technological limitations that currently prevent this technology from becoming the standard.

2.
Gels ; 10(4)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38667693

RESUMO

Biopolymeric nanoparticles (NPs) have gained significant attention in several areas as an alternative to synthetic polymeric NPs due to growing environmental and immunological concerns. Among the most promising biopolymers is poly(lactic acid) (PLA), with a reported high degree of biocompatibility and biodegradability. In this work, PLA NPs were synthesized according to a controlled gelation process using a combination of single-emulsion and nanoprecipitation methods. This study evaluated the influence of several experimental parameters for accurate control of the PLA NPs' size distribution and aggregation. Tip sonication (as the stirring method), a PLA concentration of 10 mg/mL, a PVA concentration of 2.5 mg/mL, and low-molecular-weight PLA (Mw = 5000) were established as the best experimental conditions to obtain monodisperse PLA NPs. After gelification process optimization, flutamide (FLU) was used as a model drug to evaluate the encapsulation capability of the PLA NPs. The results showed an encapsulation efficiency of 44% for this cytostatic compound. Furthermore, preliminary cell viability tests showed that the FLU@PLA NPs allowed cell viabilities above 90% up to a concentration of 20 mg/L. The comprehensive findings showcase that the PLA NPs fabricated using this straightforward gelification method hold promise for encapsulating cytostatic compounds, offering a novel avenue for precise drug delivery in cancer therapy.

3.
Front Immunol ; 14: 1168607, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37153579

RESUMO

Introduction: Osteopenia has been associated to several inflammatory conditions, including mycobacterial infections. How mycobacteria cause bone loss remains elusive, but direct bone infection may not be required. Methods: Genetically engineered mice and morphometric, transcriptomic, and functional analyses were used. Additionally, inflammatory mediators and bone turnover markers were measured in the serum of healthy controls, individuals with latent tuberculosis and patients with active tuberculosis. Results and discussion: We found that infection with Mycobacterium avium impacts bone turnover by decreasing bone formation and increasing bone resorption, in an IFNγ- and TNFα-dependent manner. IFNγ produced during infection enhanced macrophage TNFα secretion, which in turn increased the production of serum amyloid A (SAA) 3. Saa3 expression was upregulated in the bone of both M. avium- and M. tuberculosis-infected mice and SAA1 and 2 proteins (that share a high homology with murine SAA3 protein) were increased in the serum of patients with active tuberculosis. Furthermore, the increased SAA levels seen in active tuberculosis patients correlated with altered serum bone turnover markers. Additionally, human SAA proteins impaired bone matrix deposition and increased osteoclastogenesis in vitro. Overall, we report a novel crosstalk between the cytokine-SAA network operating in macrophages and bone homeostasis. These findings contribute to a better understanding of the mechanisms of bone loss during infection and open the way to pharmacological intervention. Additionally, our data and disclose SAA proteins as potential biomarkers of bone loss during infection by mycobacteria.


Assuntos
Mycobacterium tuberculosis , Proteína Amiloide A Sérica , Humanos , Camundongos , Animais , Proteína Amiloide A Sérica/genética , Proteína Amiloide A Sérica/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Osso e Ossos/metabolismo , Macrófagos/metabolismo , Citocinas/metabolismo , Mycobacterium tuberculosis/metabolismo
4.
Adv Mater ; 33(40): e2007761, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34382257

RESUMO

Polyoxometalates are an emerging class of molecular clusters, with well-defined structures and chemical compositions that are produced through simple, low-cost, and highly reproducible methods. In particular, the wheel-shaped cluster {Mo154 } is a promising photothermal agent due to its intervalence charge transfer transitions. However, its toxicity hinders its systemic administration, being the development of a localized delivery system still incipient. Herein, an injectable and self-healing hydrogel of easy preparation and administration is developed, incorporating both {Mo154 } and doxorubicin for synergistic photothermal and chemotherapy applications. The hydrogel is composed of benzylaldehyde functionalized polyethylene glycol, poly(N-isopropylacrylamide) functionalized chitosan and {Mo154 }. The gelation occurs within 60 s at room temperature, and the dual crosslinking by Schiff base and electrostatic interactions generates a dynamic network, which enables self-healing after injection. Moreover, the hydrogel delivers chemotherapeutic drugs, with a release triggered by dual near infra-red (NIR) radiation and pH changes. This stimuli-responsive release system along with the photothermal conversion ability of the hydrogel allows the simultaneous combination of photothermal and chemotherapy. This synergic system efficiently ablates the cancer tumor in vivo with no systemic toxicity. Overall, this work paves the way for the development of novel {Mo154 }-based systems, incorporated in self-healing and injectable hydrogels for dual chemo-photothermal therapy.


Assuntos
Portadores de Fármacos/química , Hidrogéis/química , Raios Infravermelhos , Terapia Fototérmica/métodos , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Doxorrubicina/química , Doxorrubicina/uso terapêutico , Humanos , Hidrogéis/farmacologia , Concentração de Íons de Hidrogênio , Camundongos Endogâmicos C57BL , Neoplasias/tratamento farmacológico , Polietilenoglicóis/química , Transplante Heterólogo
5.
Nanomaterials (Basel) ; 11(8)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34443888

RESUMO

Cellulose nanocrystals (CNCs) are elongated biobased nanostructures with unique characteristics that can be explored as nanosystems in cancer treatment. Herein, the synthesis, characterization, and cellular uptake on folate receptor (FR)-positive breast cancer cells of nanosystems based on CNCs and a chitosan (CS) derivative are investigated. The physical adsorption of the CS derivative, containing a targeting ligand (folic acid, FA) and an imaging agent (fluorescein isothiocyanate, FITC), on the surface of the CNCs was studied as an eco-friendly methodology to functionalize CNCs. The fluorescent CNCs/FA-CS-FITC nanosystems with a rod-like morphology showed good stability in simulated physiological and non-physiological conditions and non-cytotoxicity towards MDA-MB-231 breast cancer cells. These functionalized CNCs presented a concentration-dependent cellular internalization with a 5-fold increase in the fluorescence intensity for the nanosystem with the higher FA content. Furthermore, the exometabolic profile of the MDA-MB-231 cells exposed to the CNCs/FA-CS-FITC nanosystems disclosed a moderate impact on the cells' metabolic activity, limited to decreased choline uptake and increased acetate release, which implies an anti-proliferative effect. The overall results demonstrate that the CNCs/FA-CS-FITC nanosystems, prepared by an eco-friendly approach, have a high affinity towards FR-positive cancer cells and thus might be applied as nanocarriers with imaging properties for active targeted therapy.

6.
Hum Mol Genet ; 30(R1): R138-R145, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-33461217

RESUMO

Sub-Saharan Africa is the most promising region of the world to conduct high-throughput studies to unveil adaptations to infectious diseases due to several reasons, namely, the longest evolving time-depth in the Homo sapiens phylogenetic tree (at least two-third older than any other worldwide region); the continuous burden of infectious diseases (still number one in health/life threat); and the coexistence of populations practising diverse subsistence modes (nomadic or seminomadic hunter-gatherers and agropastoralists, and sedentary agriculturalists, small urban and megacity groups). In this review, we will present the most up-to-date results that shed light on three main hypotheses related with this adaptation. One is the hypothesis of coevolution between host and pathogen, given enough time for the establishment of this highly dynamic relationship. The second hypothesis enunciates that the agricultural transition was responsible for the increase of the infectious disease burden, due to the huge expansion of the sedentary human population and the cohabitation with domesticates as main reservoirs of pathogens. The third hypothesis states that the boosting of our immune system against pathogens by past selection may have resulted in maladaptation of the developed hygienic societies, leading to an increase of allergic, inflammatory and autoimmune disorders. Further work will enlighten the biological mechanisms behind these main adaptations, which can be insightful for translation into diagnosis, prognosis and treatment interventions.


Assuntos
Adaptação Fisiológica , População Negra/genética , Doenças Transmissíveis/genética , África Subsaariana , Agricultura , Humanos , Filogenia , Seleção Genética
7.
Carbohydr Polym ; 238: 116197, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32299546

RESUMO

This work focuses on exploring combinations of disintegrated bacterial cellulose nanofibres (BC) with graphene oxide (GO) (reduced and non-reduced) and phase change materials (PCMs) prepared in the form of foam-like structures. The presence of GO remarkable improves the fire-retardancy and provides dimensional stability to the foams while PCMs gives thermal energy storage capacity. The foams were exposed to methyltrimethoxysilane (MTMS) vapour to become hydrophobic which was confirmed by measuring water absorption capacity and water contact angle. To extend the multifunctionality of these nanocomposite foams, a selected composition was impregnated into an open-cell aluminium foam creating a hybrid structure (Al-BC/GO) with higher mechanical properties (increase in stress of 100 times) and high sound absorption coefficient (near 1 between 1000-4000 Hz). The low thermal conductivity confirms that this hybrid structure is a thermal insulator. These advantages highlight the potential applications of the proposed materials e.g. construction, automotive and aeronautical sectors.

8.
Materials (Basel) ; 13(5)2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32121128

RESUMO

Gold nanoparticles (AuNPs) are one of the most studied nanosystems with great potential for biomedical applications, including cancer therapy. Although some gold-based systems have been described, the use of green and faster methods that allow the control of their properties is of prime importance. Thus, the present study reports a one-minute microwave-assisted synthesis of fucoidan-coated AuNPs with controllable size and high antitumoral activity. The NPs were synthesized using a fucoidan-enriched fraction extracted from Fucus vesiculosus, as the reducing and capping agent. The ensuing monodispersed and spherical NPs exhibit tiny diameters between 5.8 and 13.4 nm for concentrations of fucoidan between 0.5 and 0.05% (w/v), respectively, as excellent colloidal stability in distinct solutions and culture media. Furthermore, the NPs present antitumoral activity against three human tumor cell lines (MNT-1, HepG2, and MG-63), and flow cytometry in combination with dark-field imaging confirmed the cellular uptake of NPs by MG-63 cell line.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31284473

RESUMO

The etiology of diseases is multifactorial, involving genetic, environmental, and lifestyle-related behaviors. Considering the pathway that involves behavioral processes, a huge body of empirical evidence has shown that some healthy behaviors such as non-smoking, any or moderate alcohol consumption, a healthy diet, (e.g., fruit and vegetable intake), and physical activity, decrease the risk of disease and mortality. This study aimed to explore the potential mediating effect of combined health behaviors on the association between interpersonal relationships and physical health in a Brazilian adult worker population from the Occupational Health Service within the oil industry in Bahia, Brazil. The sample included 611 workers, of which 567 (92.8%) were males and 44 (7.2%) females, age ranging from 18 to 73 years (M = 41.95; SD = 8.88). The significant predictors of physical health were interpersonal relationships and health behaviors. Health behaviors contributed significantly to a reduction in the effect of interpersonal relationships on physical health outcomes. As far as it is known, there has been no prior work in Brazil that simultaneously examined the best predictors of physical health in oil workers using this conceptual model. Interventions in the workplace environment need to consider health behavior as a mediator between interpersonal relationships and physical health, aligned in a global psychosocial approach to health at work.


Assuntos
Comportamentos Relacionados com a Saúde , Relações Interpessoais , Saúde Ocupacional/estatística & dados numéricos , Indústria de Petróleo e Gás , Adulto , Idoso , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
J Proteome Res ; 17(4): 1636-1646, 2018 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-29498529

RESUMO

The expansion of biomedical and therapeutic applications of silver nanoparticles (AgNPs) raises the need to further understand their biological effects on human cells. In this work, NMR metabolomics has been applied to reveal the metabolic effects of AgNPs toward human hepatoma (HepG2) cells, which are relevant with respect to nanoparticle accumulation and detoxification. Cellular responses to widely disseminated citrate-coated AgNPs (Cit30) and to emergent biogenic AgNPs prepared using an aqueous plant extract as reducing and stabilizing agent (GS30) have been compared with a view to assess the influence of nanoparticle coating on the metabolic effects produced. Subtoxic concentrations (IC5 and IC20) of both nanoparticle types caused profound changes in the cellular metabolome, suggesting adaptations in energy production processes (glucose metabolism and the phosphocreatine system), antioxidant defenses, protein degradation and lipid metabolism. These signatures were proposed to reflect mainly metabolism-mediated protective mechanisms and were found to be largely common to Cit30 and GS30 AgNPs, although differences in the magnitude of response, not captured by conventional cytotoxicity assessment, were detected. Overall, this study highlights the value of NMR metabolomics for revealing subtoxic biological effects and helping to understand cell-nanomaterial interactions.


Assuntos
Fígado/metabolismo , Metaboloma/efeitos dos fármacos , Metabolômica/métodos , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Ácido Cítrico/farmacologia , Excipientes/farmacologia , Células Hep G2 , Humanos , Fígado/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Substâncias Redutoras/farmacologia
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