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1.
Bragança; s.n; 20240000. tab..
Tese em Português | BDENF - Enfermagem | ID: biblio-1527123

RESUMO

A segurança dos doentes nos serviços de saúde, foi sempre uma preocupação dos gestores em saúde. Um dos aspetos que a pode comprometer, é a transferência de cuidados do doente entre os profissionais responsáveis por ele. Seja nas passagens de turno, ou transferências intra e inter-hospitalares. É essencial que seja estabelecida uma comunicação eficaz, de modo a assegurar a fluidez de assunção de cuidados e responsabilidades. Estes pressupostos evitam a ocorrência de efeitos adversos, de eventuais atrasos no diagnóstico e tratamentos, que podem dar origem a atrasos no restabelecimento da pessoa em situação crítica. Objetivos: Conhecer a perceção dos enfermeiros do Serviço de Urgência (SU), relativamente à informação transmitida durante as passagens de turno. Tornar mais eficaz a comunicação interpares, e garantir, como consequência, a segurança e a melhoria dos cuidados de enfermagem, nos momentos de transição de doentes, no SU. Metodologia: Trabalho realizado com base na metodologia investigação-ação, dividido em três processos metodológicos parcelares e consecutivos. Primeiramente, foi aplicado um questionário, a 59 enfermeiros em SU, com prestação direta de cuidados à pessoa em situação crítica. No segundo momento, foi realizado um diagnóstico de situação com a aplicação do Guia de Observação, durante os momentos de passagem de turno. No terceiro momento, após a análise dos resultados emergentes do Guia de Observação, foi criado, e implementado, o instrumento estruturado para aplicar nas passagens de turno, baseado na metodologia Identify, Situation, Background, Assessment e Recommendation (ISBAR), e aplicado novamente o Guia de Observação, para estudo de eficácia e/ou eficiência trazida por este instrumento. Resultados: A perceção dos enfermeiros sobre a comunicação durante as passagens de turno é favorável em relação à maioria dos aspetos abordados. Estes valorizaram a comunicação no contexto da equipa multidisciplinar, e aspetos relacionados com a importância da formação e da experiência profissional com a qualidade da comunicação. A perceção favorável do enfermeiro traduz-se no elevado nível de situações significativas (70 a 90%) que cerca de 80% enfermeiros reportam conseguir transmitir durante a passagem de turno. 36% dos participantes apontam a necessidade de melhorias, 65% relacionadas com a organização do processo de transição de cuidados e 45% com o problema das interrupções. Após a implementação da metodologia ISBAR nas passagens de turno, houve uma melhoria em vários aspetos, como se depreende da percentagem média de conformidade ser cerca de 69%, tendo melhorado cerca de 48%. O tempo de transmissão de informação aumentou, em média, 0,4 minutos por doente. Conclusão: Os resultados do presente trabalho apontam uma perspetiva favorável da perceção dos enfermeiros sobre a comunicação durante a passagem de turno, ainda que alguns aspetos tenham margem para melhoria, relacionados com a objetividade e pertinência da informação, e com a necessidade de ter um contexto calmo que favoreça a concentração, logo sem interrupções. Este contexto é, por sua vez, facilitador da mudança, como se veio a verificar ao comparar a qualidade da passagem de turno antes e depois de implementar a metodologia ISBAR, a certificação das melhorias demonstra o interesse e eficácia da sua utilização.


Patient safety in health services has always been a concern of health managers. One of the aspects that can compromise it is the transfer of the patient's care between the professionals responsible for it. Be it in handovers, or intra and inter-hospital transfers. It is essential that effective communication is established to ensure the fluidity of the assumption of care and responsibilities. These assumptions prevent the occurrence of adverse effects, possible delays in diagnosis and treatment, which can lead to delays in the recovery of the person in critical condition. Objectives: To know the nurses' perception in the Emergency Department (ED) regarding the information transmitted during handover. To make peer-to-peer communication more effective, and to ensure, consequently, the safety and improvement of nursing care, in moments of patient transition, in the ED. Methodology: This work was carried out based on the research-action methodology, divided into three partial and consecutive methodological processes. First, a questionnaire was applied to 59 nurses in the ED, with direct care provided to the critically ill person. In the second moment, a diagnosis of the situation was carried out with the application of the Observation Guide, during handovers. In the third moment, after the analysis of the results emerging from the Observation Guide, a structured instrument was created and implemented to be applied in handover, based on the Identify, Situation, Background, Assessment and Recommendation (ISBAR) methodology, and the Observation Guide was applied again to study the effectiveness and/or efficiency brought by this instrument. Results: Nurses' perception of communication during handover is favorable in relation to most of the aspects addressed. They valued communication in the context of the multidisciplinary team, and aspects related to the importance of training and professional experience with the quality of communication. The favorable nurses' perception translates into the high level of significant situations (70 to 90%) that about 80% of nurses report being able to transmit during handover. 36% of the participants point to the need for improvements, 65% related to the organization of the care transition process and 45% to the problem of interruptions. After the implementation of the ISBAR methodology in handovers, there was an improvement in several aspects, as can be seen from the average percentage of compliance being about 69%, having improved about 48%. The information transmission time increased by an average of 0.4 minutes per patient. Conclusion: The results of the present study point to a favorable perspective of nurses' perception of communication during handover, although some aspects have room for improvement, related to the objectivity and relevance of the information, and to the need to have a calm context that favors concentration, thus without interruptions. This context is a facilitator of change, as it turned out when comparing the quality of handovers before and after implementing the ISBAR methodology, the certification of improvements demonstrates the interest and effectiveness of its use.


Assuntos
Humanos , Comunicação , Serviço Hospitalar de Emergência , Enfermagem Médico-Cirúrgica
2.
Int J Pharm ; 647: 123552, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-37884216

RESUMO

Nanomaterials with near infrared light absorption can mediate an antitumoral photothermal-photodynamic response that is weakly affected by cancer cells' resistance mechanisms. Such nanosystems are commonly prepared by loading photosensitizers into nanomaterials displaying photothermal capacity, followed by functionalization to achieve biological compatibility. However, the translation of these multifunctional nanomaterials has been limited by the fact that many of the photosensitizers are not responsive to near infrared light. Furthermore, the reliance on poly(ethylene glycol) for functionalizing the nanomaterials is also not ideal due to some immunogenicity reports. Herein, a novel photoeffective near infrared light-responsive nanosystem for cancer photothermal-photodynamic therapy was assembled. For such, dopamine-reduced graphene oxide was, for the first time, functionalized with sulfobetaine methacrylate-brushes, and then loaded with IR780 (IR780/SB/DOPA-rGO). This hybrid system revealed a nanometric size distribution, optimal surface charge and colloidal stability. The interaction of IR780/SB/DOPA-rGO with near infrared light prompted a temperature increase (photothermal effect) and production of singlet oxygen (photodynamic effect). In in vitro studies, the IR780/SB/DOPA-rGO per se did not elicit cytotoxicity (viability > 78 %). In contrast, the combination of IR780/SB/DOPA-rGO with near infrared light decreased breast cancer cells' viability to just 21 %, at a very low nanomaterial dose, highlighting its potential for cancer photothermal-photodynamic therapy.


Assuntos
Neoplasias , Fotoquimioterapia , Fármacos Fotossensibilizantes , Di-Hidroxifenilalanina , Fototerapia , Linhagem Celular Tumoral , Neoplasias/terapia
3.
Biomater Sci ; 11(18): 6082-6108, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37539702

RESUMO

Progress in the nanotechnology field has led to the development of a new class of materials capable of producing a temperature increase triggered by near infrared light. These photothermal nanostructures have been extensively explored in the ablation of cancer cells. Nevertheless, the available data in the literature have exposed that systemically administered nanomaterials have a poor tumor-homing capacity, hindering their full therapeutic potential. This paradigm shift has propelled the development of new injectable hydrogels for the local delivery of nanomaterials aimed at cancer photothermal therapy. These hydrogels can be assembled at the tumor site after injection (in situ forming) or can undergo a gel-sol-gel transition during injection (shear-thinning/self-healing). Besides incorporating photothermal nanostructures, these injectable hydrogels can also incorporate or be combined with other agents, paving the way for an improved therapeutic outcome. This review analyses the application of injectable hydrogels for the local delivery of nanomaterials aimed at cancer photothermal therapy as well as their combination with photodynamic-, chemo-, immuno- and radio-therapies.


Assuntos
Nanoestruturas , Neoplasias , Humanos , Fototerapia , Hidrogéis/química , Terapia Fototérmica , Nanoestruturas/química , Neoplasias/tratamento farmacológico
4.
Nanomaterials (Basel) ; 13(11)2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37299655

RESUMO

Hospitals and nursing home wards are areas prone to the propagation of infections and are of particular concern regarding the spreading of dangerous viruses and multidrug-resistant bacteria (MDRB). MDRB infections comprise approximately 20% of cases in hospitals and nursing homes. Healthcare textiles, such as blankets, are ubiquitous in hospitals and nursing home wards and may be easily shared between patients/users without an adequate pre-cleaning process. Therefore, functionalizing these textiles with antimicrobial properties may considerably reduce the microbial load and prevent the propagation of infections, including MDRB. Blankets are mainly comprised of knitted cotton (CO), polyester (PES), and cotton-polyester (CO-PES). These fabrics were functionalized with novel gold-hydroxyapatite nanoparticles (AuNPs-HAp) that possess antimicrobial properties, due to the presence of the AuNPs' amine and carboxyl groups, and low propensity to display toxicity. For optimal functionalization of the knitted fabrics, two pre-treatments, four different surfactants, and two incorporation processes were evaluated. Furthermore, exhaustion parameters (time and temperature) were subjected to a design of experiments (DoE) optimization. The concentration of AuNPs-HAp in the fabrics and their washing fastness were critical factors assessed through color difference (ΔE). The best performing knitted fabric was half bleached CO, functionalized using a surfactant combination of Imerol® Jet-B (surfactant A) and Luprintol® Emulsifier PE New (surfactant D) through exhaustion at 70 °C for 10 min. This knitted CO displayed antibacterial properties even after 20 washing cycles, showing its potential to be used in comfort textiles within healthcare environments.

5.
Biomater Adv ; 151: 213443, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37146526

RESUMO

Photothermal therapy has emerged as a new promising strategy for the management of cancer, either alone or combined with other therapeutics, such as chemotherapy. The use of nanoparticles for multimodal therapy can improve treatment performance and reduce drug doses and associated side effects. Here we propose the development of a novel multifunctional nanosystem based on solid lipid nanoparticles co-loaded with gold nanorods and mitoxantrone and functionalized with folic acid for dual photothermal therapy and chemotherapy of breast cancer. Nanoparticles were produced using an economically affordable method and presented suitable physicochemical properties for tumor passive accumulation. Upon Near-Infrared irradiation (808 nm, 1.7 W cm-2, 5 min), nanoparticles could effectively mediate a temperature increase of >20 °C. Moreover, exposure to light resulted in an enhanced release of Mitoxantrone. Furthermore, nanoparticles were non-hemolytic and well tolerated by healthy cells even at high concentrations. The active targeting strategy was found to be successful, as shown by the greater accumulation of the functionalized nanoparticles in MCF-7 cells. Finally, the combined effects of chemotherapy, light-induced drug release and photothermal therapy significantly enhanced breast cancer cell death. Overall, these results demonstrate that the developed lipid nanosystem is an efficient vehicle for breast cancer multimodal therapy.


Assuntos
Neoplasias da Mama , Nanopartículas , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Mitoxantrona/uso terapêutico , Terapia Fototérmica , Nanopartículas/uso terapêutico , Nanopartículas/química
6.
Polymers (Basel) ; 15(7)2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37050344

RESUMO

Textiles are important components for the development of lightweight and flexible displays useful in smart materials. In particular, halochromic textiles are fibrous materials with a color-changing ability triggered by pH variations mainly based on pH-sensitive dye molecules. Recently, a novel class of 2-aminoimidazole azo dyes was developed with distinct substituent patterns. In this work, silk fabric was functionalized through exhaustion for the first time with one of these dyes (AzoIz.Pip). The halochromic properties of the dye were assessed in an aqueous solution and after silk functionalization. The solutions and the fabrics were thoroughly analyzed by ultraviolet-visible (UV-vis) spectra, color strength (K/S), color difference (∆E), CIE L*a*b* coordinates, and the ultraviolet protection factor (UPF). The dyeing process was optimized, and the halochromic performance (and reversibility) was assessed in universal Britton-Robinson buffers (ranging from pH 3 to 12) and artificial body fluids (acid and alkaline perspiration, and wound exudate). AzoIz.Pip showed vibrant colors and attractive halochromic properties with a hypsochromic shift from blue (557 nm) to magenta (536 nm) in aqueous buffered solutions. Similarly, the functionalized silk showed a shift in wavelength of the maximum K/S value from 590 nm to 560 nm when pH increases. The silk fabric showed a high affinity to AzoIz.Pip, and promoted additional color stabilization of the dye, avoiding color loss as observed when the dye is in solution at alkaline pH after 24 h. The color reversibility was effective up to the fourth cycle and the fastness tests denoted suitable results, except washing fastness. The cytotoxicity of the silk fabric extracts was assessed, depicting reduced viability of HaCaT cells to <70% only when the dye concentration in the fabric is higher or equal to 64 µg·mL-1. Nevertheless, lower concentrations were also very effective for the halochromic performance in silk. These materials can thus be a helpful tool for developing sensors in several sectors such as biomedicine, packaging, filtration, agriculture, protective apparel, sports, camouflage, architecture, and design.

7.
Cells ; 12(3)2023 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-36766724

RESUMO

Major depressive disorder (MDD) is a multidimensional psychiatric disorder that is estimated to affect around 350 million people worldwide. Generating valid and effective animal models of depression is critical and has been challenging for neuroscience researchers. For preclinical studies, models based on stress exposure, such as unpredictable chronic mild stress (uCMS), are amongst the most reliable and used, despite presenting concerns related to the standardization of protocols and time consumption for operators. To overcome these issues, we developed an automated system to expose rodents to a standard uCMS protocol. Here, we compared manual (uCMS) and automated (auCMS) stress-exposure protocols. The data shows that the impact of the uCMS exposure by both methods was similar in terms of behavioral (cognition, mood, and anxiety) and physiological (cell proliferation and endocrine variations) measurements. Given the advantages of time and standardization, this automated method represents a step forward in this field of preclinical research.


Assuntos
Transtorno Depressivo Maior , Ratos , Animais , Ansiedade , Cognição
8.
Int J Pharm ; 635: 122713, 2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-36764414

RESUMO

Nano-sized materials have been widely explored in the biomedicine field, especially due to their ability to encapsulate drugs intended to be delivered to cancer cells. However, systemically administered nanomaterials face several barriers that can hinder their tumor-homing capacity. In this way, researchers are now focusing their efforts in developing technologies that can deliver the nanoparticles directly into the tumor tissue. Particularly, hydrogels assembled using Thiol-Maleimide Michael type additions are emerging for this purpose due to their capacity to incorporate high nanoparticles' doses in a compact 3D structure as well as good chemical selectivity, biocompatibility, and straightforward preparation. Nevertheless, such hydrogels have been mostly prepared using synthetic polymers, which is not ideal due to their poor biodegradability. In this work, a novel natural polymer-based Thiol-Maleimide hydrogel was produced for application in breast cancer chemo-photothermal therapy. To obtain natural polymers compatible with this crosslinking chemistry, Hyaluronic acid was endowed with Thiol groups and deacetylated Chitosan was grafted with Maleimide groups. Parallelly, Doxorubicin loaded Dopamine-reduced graphene oxide (DOX/DOPA-rGO) was prepared for attaining Near Infrared (NIR) light responsive chemo-photothermal nanoagents. By simply mixing Hyaluronic Acid-Thiol, deacetylated Chitosan-Maleimide and DOX/DOPA-rGO, Thiol-Maleimide crosslinked hydrogels incorporating this nanomaterial could be assembled (DOX/DOPA-rGO@TMgel). When breast cancer cells were incubated with DOPA-rGO@TMgel and exposed to NIR light (photothermal therapy), their viability was reduced to about 59 %. On the other hand, DOX/DOPA-rGO@TMgel (chemotherapy) reduced cancer cells' viability to 50 %. In stark contrast, the combined action of DOX/DOPA-rGO@TMgel and NIR light decreased breast cancer cells' viability to just 21 %, highlighting its chemo-photothermal potential.


Assuntos
Neoplasias da Mama , Quitosana , Grafite , Hipertermia Induzida , Nanoestruturas , Humanos , Feminino , Grafite/química , Terapia Fototérmica , Hidrogéis/química , Compostos de Sulfidrila , Ácido Hialurônico/química , Doxorrubicina , Neoplasias da Mama/tratamento farmacológico , Polímeros/química , Maleimidas , Di-Hidroxifenilalanina , Fototerapia , Linhagem Celular Tumoral
9.
Eur J Pharm Biopharm ; 184: 7-15, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36682512

RESUMO

Near infrared (NIR) light-responsive nanomaterials hold potential to mediate combinatorial therapies targeting several cancer hallmarks. When irradiated, these nanomaterials produce reactive oxygen species (photodynamic therapy) and/or a temperature increase (photothermal therapy). These events can damage cancer cells and trigger the release of drugs from the nanomaterials' core. However, engineering nanomaterials for cancer chemo-photodynamic/photothermal therapy is a complex process. First, nanomaterials with photothermal capacity are synthesized, being then loaded with photosensitizers plus chemotherapeutics, and, finally functionalized with polymers for achieving suitable biological properties. To overcome this limitation, in this work, a novel straightforward approach to attain NIR light-responsive nanosystems for cancer chemo-photodynamic/photothermal therapy was established. Such was accomplished by synthesizing poly(2-ethyl-2-oxazoline)-IR780 amphiphilic conjugates, which can be assembled into nanoparticles with photodynamic/photothermal capabilities that simultaneously encapsulate Doxorubicin (DOX/PEtOx-IR NPs). The DOX/PEtOx-IR NPs presented a suitable size and surface charge for cancer-related applications. When irradiated with NIR light, the DOX/PEtOx-IR NPs produced singlet oxygen as well as a smaller thermic effect that boosted the release of DOX by 1.7-times. In the in vitro studies, the combination of DOX/PEtOx-IR NPs and NIR light could completely ablate breast cancer cells (viability ≈ 4 %), demonstrating the enhanced outcome arising from the nanomaterials' chemo-photodynamic/photothermal therapy.


Assuntos
Nanopartículas , Nanoestruturas , Neoplasias , Fotoquimioterapia , Doxorrubicina , Fármacos Fotossensibilizantes , Linhagem Celular Tumoral
10.
Nutrients ; 14(23)2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36500987

RESUMO

A parental child-centered feeding approach is likely to keep children's biological mechanisms activated while eating, protecting them in an obesogenic context. However, few feeding practice measures assess parents' behaviors to guide and prompt children to identify and respond appropriately to their signs of hunger and satiety. We aimed to develop and study the reliability, validity, and measurement invariance of a new scale to assess parental feeding practices to promote children's self-regulation of food intake. To pursue this aim, we conducted two descriptive, cross-sectional, online studies in Portugal in an online format; a total of 536 parents of 2- to 6-year-old children completed the evaluation protocol. Factorial analysis findings support the theoretical organization proposed for the scale. The confirmatory factorial analysis supported a first-order factor structure with two subscales, Prompting for eating self-regulation and Teaching about eating consequences, with eight items in total. Both scales presented good internal consistency and adequate temporal stability, with a significant, positive, and moderate relationship. The results showed metric invariance for the child's sex. Both types of practices were positively correlated with the child's enjoyment of food. Prompting for eating self-regulation showed negative associations with parents' emotional lack of control, children's satiety responsiveness, slowness in eating, and fussiness. Preliminary studies confirmed both the validity and reliability of the instrument and the adequacy of adopting a self-regulatory approach when assessing child-centered feeding practices. Combining this instrument with others that assess coercive practices can be beneficial to capture ineffective parents' behaviors on children's eating self-regulation.


Assuntos
Comportamento Infantil , Autocontrole , Humanos , Criança , Pré-Escolar , Comportamento Infantil/psicologia , Estudos Transversais , Reprodutibilidade dos Testes , Inquéritos e Questionários , Pais/psicologia , Comportamento Alimentar/psicologia , Poder Familiar , Ingestão de Alimentos/psicologia
11.
Pharmaceutics ; 14(5)2022 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-35631600

RESUMO

The development of strategies capable of eliminating metastasized cancer cells and preventing tumor recurrence is an exciting and extremely important area of research. In this regard, therapeutic approaches that explore the synergies between nanomaterial-mediated phototherapies and immunostimulants/immune checkpoint inhibitors have been yielding remarkable results in pre-clinical cancer models. These nanomaterials can accumulate in tumors and trigger, after irradiation of the primary tumor with near infrared light, a localized temperature increase and/or reactive oxygen species. These effects caused damage in cancer cells at the primary site and can also (i) relieve tumor hypoxia, (ii) release tumor-associated antigens and danger-associated molecular patterns, and (iii) induced a pro-inflammatory response. Such events will then synergize with the activity of immunostimulants and immune checkpoint inhibitors, paving the way for strong T cell responses against metastasized cancer cells and the creation of immune memory. Among the different nanomaterials aimed for cancer immuno-phototherapy, those incorporating near infrared-absorbing heptamethine cyanines (Indocyanine Green, IR775, IR780, IR797, IR820) have been showing promising results due to their multifunctionality, safety, and straightforward formulation. In this review, combined approaches based on phototherapies mediated by heptamethine cyanine-loaded nanomaterials and immunostimulants/immune checkpoint inhibitor actions are analyzed, focusing on their ability to modulate the action of the different immune system cells, eliminate metastasized cancer cells, and prevent tumor recurrence.

12.
Nanomaterials (Basel) ; 12(6)2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35335819

RESUMO

Nanotechnology is a powerful tool for engineering functional materials that has the potential to transform textiles into high-performance, value-added products. In recent years, there has been considerable interest in the development of functional textiles using metal nanoparticles (MNPs). The incorporation of MNPs in textiles allows for the obtention of multifunctional properties, such as ultraviolet (UV) protection, self-cleaning, and electrical conductivity, as well as antimicrobial, antistatic, antiwrinkle, and flame retardant properties, without compromising the inherent characteristics of the textile. Environmental sustainability is also one of the main motivations in development and innovation in the textile industry. Thus, the synthesis of MNPs using ecofriendly sources, such as polysaccharides, is of high importance. The main functions of polysaccharides in these processes are the reduction and stabilization of MNPs, as well as the adhesion of MNPs onto fabrics. This review covers the major research attempts to obtain textiles with different functional properties using polysaccharides and MNPs. The main polysaccharides reported include chitosan, alginate, starch, cyclodextrins, and cellulose, with silver, zinc, copper, and titanium being the most explored MNPs. The potential applications of these functionalized textiles are also reported, and they include healthcare (wound dressing, drug release), protection (antimicrobial activity, UV protection, flame retardant), and environmental remediation (catalysts).

13.
Nanomedicine (Lond) ; 17(27): 2057-2072, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36803049

RESUMO

Aims: To address the limitations of IR780 by preparing hydrophilic polymer-IR780 conjugates and to employ these conjugates in the assembly of nanoparticles (NPs) intended for cancer photothermal therapy. Materials & methods: The cyclohexenyl ring of IR780 was conjugated for the first time with thiol-terminated poly(2-ethyl-2-oxazoline) (PEtOx). This novel poly(2-ethyl-2-oxazoline)-IR780 (PEtOx-IR) conjugate was combined with D-α-tocopheryl succinate (TOS), leading to the assembly of mixed NPs (PEtOx-IR/TOS NPs). Results: PEtOx-IR/TOS NPs displayed optimal colloidal stability as well as cytocompatibility in healthy cells at doses within the therapeutic range. In turn, the combination of PEtOx-IR/TOS NPs and near-infrared light reduced heterotypic breast cancer spheroid viability to just 15%. Conclusion: PEtOx-IR/TOS NPs are promising agents for breast cancer photothermal therapy.


Conventional anticancer approaches are often associated with severe side effects. Herein, the authors assembled a novel nanoparticle whose therapeutic effect is triggered by laser light. In in vitro assays, the produced nanomaterial was able to, after interacting with laser light, reduce the viability of classic and advanced cancer models. In these conditions, but in the absence of laser light, no cytotoxicity was observed. In this way, the on-demand effect (triggered by laser light) may contribute to reduced side effects. Moreover, the produced nanoparticle revealed good stability, which is important for its future translation.


Assuntos
Neoplasias da Mama , Nanopartículas , Fotoquimioterapia , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Fototerapia , Nanopartículas/uso terapêutico , alfa-Tocoferol/uso terapêutico , Linhagem Celular Tumoral
14.
Mater Sci Eng C Mater Biol Appl ; 130: 112468, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34702543

RESUMO

The high near infrared (NIR) absorption displayed by reduced graphene oxide (rGO) nanostructures renders them a great potential for application in cancer photothermal therapy. However, the production of this material often relies on the use of hydrazine as a reductant, leading to poor biocompatibility and environmental-related issues. In addition, to improve rGO colloidal stability, this material has been functionalized with poly(ethylene glycol). However, recent studies have reported the immunogenicity of poly(ethylene glycol)-based coatings. In this work, the production of rGO, by using dopamine as the reducing agent, was optimized considering the size distribution and NIR absorption of the attained materials. The obtained results unveiled that the rGO produced by using a 1:5 graphene oxide:dopamine weight ratio and a reaction time of 4 h (termed as DOPA-rGO) displayed the highest NIR absorption while retaining its nanometric size distribution. Subsequently, the DOPA-rGO was functionalized with thiol-terminated poly(2-ethyl-2-oxazoline) (P-DOPA-rGO), revealing suitable physicochemical features, colloidal stability and cytocompatibility. When irradiated with NIR light, the P-DOPA-rGO could produce a temperature increase (ΔT) of 36 °C (75 µg/mL; 808 nm, 1.7 W/cm2, 5 min). The photothermal therapy mediated by P-DOPA-rGO was capable of ablating breast cancer cells monolayers (viability < 3%) and could reduce heterotypic breast cancer spheroids' viability to just 30%. Overall, P-DOPA-rGO holds a great potential for application in breast cancer photothermal therapy.


Assuntos
Grafite , Neoplasias , Dopamina , Neoplasias/tratamento farmacológico , Fototerapia , Terapia Fototérmica , Poliaminas
15.
Int J Pharm ; 607: 121044, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34450227

RESUMO

Breast cancer is the leading cause of cancer-related deaths among women worldwide. The conventional chemotherapeutic regimens used in the treatment of this disease often lead to severe side-effects and reduced efficacy. In this study, a novel drug delivery system for the chemotherapeutic drug mitoxantrone (Mito) was developed using solid lipid nanoparticles (SLN). The production of the SLN was carried out using an organic-solvent-free, low-cost method and optimized using a Box-Behnken design. SLN presented adequate size for cancer-related applications, more than 90% of EE% and remained stable for at least 6 months. A much higher drug release was obtained at acidic pH (mimicking the endosomal compartment) than plasmatic pH, highlighting the potential of the nanosystem for tumor drug delivery. Additionally, SLN were non-hemolytic and cytocompatible, even at high concentrations of lipid. A significantly higher anti-cancer efficacy was obtained for Mito-loaded SLN comparing to the free drug at different concentrations in MCF-7 2D models. Finally, the nanoformulation was evaluated in heterotypic breast cancer spheroids showing capacity to penetrate the tridimensional structure and ability to induce a high anti-tumoral effect, similarly to the free drug. Overall, these results support that the developed SLN are effective Mito nanocarriers for the treatment of breast cancer.


Assuntos
Antineoplásicos , Neoplasias da Mama , Nanopartículas , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Portadores de Fármacos/uso terapêutico , Feminino , Humanos , Lipídeos , Mitoxantrona , Tamanho da Partícula
16.
Int J Pharm ; 600: 120510, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33766636

RESUMO

Chemo-photothermal therapy (chemo-PTT) mediated by nanomaterials holds a great potential for cancer treatment. However, the tumor uptake of the systemically administered nanomaterials was recently found to be below 1%. To address this limitation, the development of injectable tridimensional polymeric matrices capable of delivering nanomaterials directly into the tumor site appears to be a promising approach. In this work, an injectable in situ forming ionotropically crosslinked chitosan-based hydrogel co-incorporating IR780 loaded nanoparticles (IR/BPN) and Doxorubicin (DOX) loaded nanoparticles (DOX/TPN) was developed for application in breast cancer chemo-PTT. The produced hydrogels (IR/BPN@Gel and IR/BPN+DOX/TPN@Gel) displayed suitable physicochemical properties and produced a temperature increase of about 9.1 °C upon exposure to Near Infrared (NIR) light. As importantly, the NIR-light exposure also increased the release of DOX from the hydrogel by 1.7-times. In the in vitro studies, the combination of IR/BPN@Gel with NIR light (photothermal therapy) led to a reduction in the viability of breast cancer cells to 35%. On the other hand, the non-irradiated IR/BPN+DOX/TPN@Gel (chemotherapy) only diminished cancer cells' viability to 85%. In contrast, the combined action of IR/BPN+DOX/TPN@Gel and NIR light reduced cancer cells' viability to about 9%, demonstrating its potential for breast cancer chemo-PTT.


Assuntos
Neoplasias da Mama , Hipertermia Induzida , Nanopartículas , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Doxorrubicina , Feminino , Humanos , Hidrogéis , Fototerapia , Terapia Fototérmica
17.
Nanomedicine (Lond) ; 16(6): 453-464, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33660547

RESUMO

Aim: Enhance the colloidal stability and photothermal capacity of graphene oxide (GO) by functionalizing it with sulfobetaine methacrylate (SBMA)-grafted bovine serum albumin (BSA; i.e., SBMA-g-BSA) and by loading IR780, respectively. Materials & methods: SBMA-g-BSA coating and IR780 loading into GO was achieved through a simple sonication process. Results: SBMA-g-BSA-functionalized GO (SBMA-BSA/GO) presented an adequate size distribution and cytocompatibility. When in contact with biologically relevant media, the size of the SBMA-BSA/GO only increased by 8%. By loading IR780 into SBMA-BSA/GO, its photothermal capacity increased by twofold. The combination of near infrared light with SBMA-BSA/GO did not induce photocytotoxicity on breast cancer cells. In contrast, the interaction of IR780-loaded SBMA-BSA/GO with near infrared light caused the ablation of cancer cells. Conclusion: IR780-loaded SBMA-BSA/GO displayed an improved colloidal stability and phototherapeutic capacity.


Assuntos
Neoplasias da Mama/terapia , Betaína/análogos & derivados , Grafite , Indóis , Metacrilatos , Fototerapia
18.
Biotechnol J ; 15(12): e2000219, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33063471

RESUMO

Combinatorial cancer therapies mediated by nanomaterials can potentially overcome the limitations of conventional treatments. These therapies are generally investigated using 2D in vitro cancer models, leading to an inaccurate screening. Recently, 3D in vitro spheroids have emerged in the preclinical testing stage of nanomedicines due to their ability to mimic key features of the in vivo solid tumors. Investigate the chemo-photothermal therapy mediated by Doxorubicin and IR780 loaded sulfobetaine methacrylate functionalized nanoparticles, for the first time, using monolayers of cancer cells and spheroids. In the 2D cancer models, the nanomaterials' mediated photothermal therapy, chemotherapy, and chemo-photothermal therapy reduced cancer cells' viability to about 58%, 29%, and 1%, respectively. Interestingly, when the nanomaterials' mediated photothermal therapy is tested on 3D spheroids, no cytotoxic effect is noticed. In contrast, the nanostructures' induced chemotherapy decreased spheroids' viability to 42%. On the other hand, nanomaterials' mediated chemo-photothermal therapy diminished spheroids' viability to 16%, being the most promising therapeutic modality. These results demonstrate the importance of using 3D spheroids during the in vitro screening of single/combinatorial therapies mediated by nanomaterials.


Assuntos
Nanopartículas , Neoplasias , Betaína/análogos & derivados , Humanos , Metacrilatos , Neoplasias/terapia , Fototerapia , Terapia Fototérmica
19.
Mater Sci Eng C Mater Biol Appl ; 117: 111294, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32919655

RESUMO

Functionalized graphene oxide (GO) and reduced GO (rGO) based nanomaterials hold a great potential for cancer photothermal therapy. However, their systemic administration has been associated with an accelerated blood clearance and/or with suboptimal tumor uptake. To address these limitations, the local delivery of GO/rGO to the tumor site by 3D matrices arises as a promising strategy. In this work, injectable chitosan-agarose in situ forming thermo-responsive hydrogels incorporating GO (thermogel-GO) or rGO (thermogel-rGO) were prepared for the first time. The hydrogels displayed suitable injectability and gelation time, as well as good physicochemical properties and cytocompatibility. When irradiated with near infrared (NIR) light, the thermogel-rGO produced a 3.8-times higher temperature increase than thermogel-GO, thus decreasing breast cancer cells' viability to 60%. By incorporating an optimized molar ratio of the Doxorubicin:Ibuprofen combination on thermogel-rGO, this formulation mediated a chemo-photothermal effect that further diminished cancer cells' viability to 34%. In addition, the hydrogels' antibacterial activity was further enhanced upon NIR laser irradiation, which is an important feature considering the possible risk of infection at the site of administration. Overall, thermogel-rGO is a promising injectable in situ forming hydrogel for combinatorial chemo-photothermal therapy of breast cancer cells and NIR light enhanced antibacterial applications.


Assuntos
Grafite , Neoplasias , Antibacterianos/farmacologia , Hidrogéis , Fototerapia , Terapia Fototérmica
20.
Nanomedicine (Lond) ; 15(15): 1513-1525, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32552537

RESUMO

The use of nanomedicines for cancer treatment holds a great potential due to their improved efficacy and safety. During the nanomedicine preclinical in vitro evaluation stage, these are mainly tested on cell culture monolayers. However, these 2D models are an unrealistic representation of the in vivo tumors, leading to an inaccurate screening of the candidate formulations. To address this problem, spheroids are emerging as an additional tool to validate the efficacy of new therapeutics due to the ability of these 3D in vitro cancer models to mimic the key features displayed by in vivo solid tumors. In this review, the application of spheroids for the evaluation of nanomedicines' physicochemical properties and therapeutic efficacy is discussed.


Assuntos
Nanomedicina , Neoplasias , Técnicas de Cultura de Células , Humanos , Neoplasias/tratamento farmacológico , Esferoides Celulares
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