Browsing by Author "Dias, Diana Rodrigues"
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- Desenvolvimento de nanopartículas inorgânicas para aplicações terapêuticasPublication . Dias, Diana Rodrigues; Correia, Ilídio Joaquim Sobreira; Moreira, André FerreiraNowadays, cancer is a leading cause of mortality among the worldwide population, for which the currently available treatments display a limited efficacy. Chemotherapy, the main therapeutic approach used for the treatment of this disease, has a sub-optimal effect due to the weak selectivity for cancer cells and rapid degradation of chemotherapeutic agents. Motivated by this alarming scenario, Nanotechnology applied to cancer-related topics has been growing for improving cancer diagnosis and survival rates. In this field, the design of nanoparticles is a promising approach, since these platforms can provide protection to drugs and decrease their interaction with healthy tissues. Among the several materials studied, gold nanoparticles with a mesoporous silica shell are promising hybrid nanostructures for cancer therapy. In this thesis, nanoparticles composed of a gold core and a silica shell (Au-MSSs) with spherical or rod-like shape were produced, in order to disclose the effect of nanomaterials shape on the nanoparticle properties, such as their drug loading capacity and release profile, biocompatibility, cellular uptake and cytotoxic effect towards cancer cells. Both Au-MSS nanoparticles showed adequate sizes for a possible passive accumulation in tumor tissues. Moreover, the optical properties displayed by Au-MSS rods allowed their application in photothermal therapy. Furthermore, the spherical nanoparticles presented an improved Dox drug encapsulation efficiency (80%) when compared to that of rod-shaped (52%). However, despite the lower Dox loaded in the Au-MSS rods, these particles delivered a higher quantity of drug to cancer cells, which indicates that Au-MSS rods are more uptaken by cancer cells. In addition, the in vitro experiments also revealed that both Au-MSSs demonstrated a higher cytotoxic effect against cancer cells than free Dox, which is crucial for cancer therapy. Moreover, the Dox loaded rod-shaped nanoparticles irradiated with near-infrared light produced an increased therapeutic effect on cancer cells, when compared to the spherical particles, which results from the rods capacity to combine chemo- and photothermal therapeutic actions. In summary, the results presented in this thesis confirm the effect of nanoparticle shape on its performance on cancer therapy. Further, depending on the desired application, the shape and the type of nanoparticle should be taken into account towards the development of a more personalized and effective therapy.
- RIT Evolution - Career Management PlatformPublication . Dias, Diana Rodrigues; Neves, João Carlos Raposo; Inácio, Pedro Ricardo Morais; Almeida, Miguel RisoBusiness world experiences a continuous evolution, so it is also needed an adjustment in enterprise career. This way, ReadinessIT developed a new career model, arising the need of a suitable platform to management the model, the Evolution platform. Thus, the main goal of this internship is the development of Evolution platform and its availability to ReadinessIT community. The Evolution is developed in Outsystems technology, and displays two main components, the Backoffice to support the model management and configuration, and also, the End User component, available to all employees. The platform supports all the included flows in the model, such as appraisals, recognitions, trainings and approvals. All the tasks related to planning, design, definition, implementation, testing and deployment of the application were carried out during this project, and are presented and discussed in this document. Currently, some functionalities are in used by all ReadinessIT collaborators according to its priorities, and the remaining are completed developed.
- Stimuli-responsive mesoporous silica nanoparticles for cancer therapy: A reviewPublication . Moreira, André; Dias, Diana Rodrigues; Correia, Ilídio Joaquim SobreiraThe application of nanocarriers as selective drug delivery platforms, as imaging or as diagnostic agents has been evaluated in several studies in the area of biomedicine, namely for cancer therapy. Such systems have the potential to perform a controlled and site-specific delivery of therapeutic agents leading to a reduction of side effects and, ultimately, to an improved therapeutic outcome. Among the different nanocarriers developed so far, mesoporous silica nanoparticles have attracted the attention of the scientific community for being applied as drug delivery systems that are capable of controlling, both in space and time, the drug release. In this review, the modifications performed, so far, on mesoporous silica nanoparticles to imprint them a stimulus responsive behavior (namely, pH, redox potential, adenosine triphosphate, enzyme or temperature) in order to allow their application in cancer therapy are highlighted.
- Strategies to Improve Cancer Photothermal Therapy Mediated by NanomaterialsPublication . Diogo, Duarte Miguel de Melo; Silva, Cleide Isabel Pais; Dias, Diana Rodrigues; Moreira, André; Correia, Ilídio Joaquim SobreiraThe deployment of hyperthermia‐based treatments for cancer therapy has captured the attention of different researchers worldwide. In particular, the application of light‐responsive nanomaterials to mediate hyperthermia has revealed promising results in several pre‐clinical assays. Unlike conventional therapies, these nanostructures can display a preferential tumor accumulation and thus mediate, upon irradiation with near‐infrared light, a selective hyperthermic effect with temporal resolution. Different types of nanomaterials such as those based on gold, carbon, copper, molybdenum, tungsten, iron, palladium and conjugated polymers have been used for this photothermal modality. This progress report summarizes the different strategies that have been applied so far for increasing the efficacy of the photothermal therapeutic effect mediated by nanomaterials, namely those that improve the accumulation of nanomaterials in tumors (e.g. by changing the corona composition or through the functionalization with targeting ligands), increase nanomaterials' intrinsic capacity to generate photoinduced heat (e.g. by synthesizing new nanomaterials or assembling nanostructures) or by optimizing the parameters related to the laser light used in the irradiation process (e.g. by modulating the radiation wavelength). Overall, the development of new strategies or the optimization and combination of the existing ones will surely give a major contribution for the application of nanomaterials in cancer PTT.
- The effect of the shape of gold core-mesoporous silica shell nanoparticles on the cellular behavior and tumor spheroid penetrationPublication . Dias, Diana Rodrigues; Moreira, André; Correia, Ilídio Joaquim SobreiraSize, surface charge, and shape have a huge influence on the behavior, cellular uptake, and cytotoxic profile of nanoparticles. Herein, gold core and silica shell based nanoparticles (Au–MSSs) with spherical or rod-like shape were produced, in order to disclose the effect of the shape of nanomaterials on the cellular uptake, reactive oxygen species (ROS) production, 3D tumor spheroid penetration and cytotoxicity towards cancer cells. The Au–MSS spheres induced greater reduction of the ROS content of cancer cells and also displayed a more homogeneous distribution and penetration in 3D tumor spheroids. However, the Au–MSS rods show enhanced cellular migration and uptake in 2D cell cultures, which results in a higher drug delivering capacity. Furthermore, the Au–MSS rods displayed an enhanced cellular cytotoxicity upon laser irradiation (808 nm, 1.7 W cm−2, 10 min), where less than 10% of cells remained viable. In addition, both Au–MSSs have the potential to be used as imaging agents, which further expands their applicability as theranostic agents in the biomedical area. In summary, the obtained results show that the shape of Au–MSSs is crucial for their biological performance, which will have a great influence on their therapeutic outcome. Therefore, our findings may provide useful information for the development and design of new drug delivery systems towards a more effective therapy.
- Thermo- and pH-responsive nano-in-micro particles for combinatorial drug delivery to cancer cellsPublication . Moreira, André; Dias, Diana Rodrigues; Costa, Elisabete C.; Correia, Ilídio Joaquim SobreiraDrug combinatorial therapy has been gaining the scientific community attention as a suitable approach to increase treatments efficacy and promote cancer eradication. In this study, a new pH- and thermo- responsive carrier was developed by combining doxorubicin-loaded gold-core silica shell nanorods with salicylic acid loaded poly (lactic-co-glycolic acid) based microparticles (NIMPS). The obtained results showed that the drugs and nanorods release could be triggered by the near-infrared (NIR) laser irradiation or by the exposition to an acidic environment. The in vitro 2D cell studies showed that the NIMPS are biocompatible and easily uptaken by HeLa cells. In addition, 3D cell culture models revealed that the NIMPS administration, combined with the NIR laser irradiation, was capable of reducing the size of the HeLa spheroids up to 48%. Overall, the attained data support the application of the nano-in-micro spheres as a dual stimuli responsive drug carrier system for the local administration of combined therapies to cervical cancer cells.