Adriana Oliveira Santos

Prof. Dr. Adriana Oliveira Santos

University of Beira Interior, Covilhã, Castelo Branco, Portugal
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Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2018 in Journal of Controlled Release
Verified
Journal Article
Closed access
PPPatrícia C. Pires
Patrícia C. Pires
ASAdriana Oliveira Santos
Adriana Oliveira Santos

8 March 2022 in Pharmaceutics
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Journal Article
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PPPatrícia C. Pires
Patrícia C. Pires
Márcio José de Abreu Marques RodriguesMárcio José de Abreu Marques Rodrigues
Márcio José de Abreu Marques Rodrigues
Gilberto AlvesGilberto Alves
Gilberto Alves
ASAdriana Oliveira Santos
Adriana Oliveira Santos
Intranasal administration is a promising route for brain drug delivery. However, it can be difficult to formulate drugs that have low water solubility into high strength intranasal solutions. Hence, the purpose of this work was to review the strategies that have been used to increase drug strength in intranasal liquid formulations. Three main groups of strategies are: the use of solubilizers (change in pH, complexation and the use cosolvents/surfactants); incorporation of the drugs into a carrier nanosystem; modifications of the molecules themselves (use of salts or hydrophilic prodrugs). The use of high amounts of cosolvents and/or surfactants and pH decrease below 4 usually lead to local adverse effects, such as nasal and upper respiratory tract irritation. Cyclodextrins and (many) different carrier nanosystems, on the other hand, could be safer for intranasal administration at reasonably high concentrations, depending on selected excipients and their dose. While added attributes such as enhanced permeation, sustained delivery, or increased direct brain transport could be achieved, a great effort of optimization will be required. On the other hand, hydrophilic prodrugs, whether co-administered with a converting enzyme or not, can be used at very high concentrations, and have resulted in a fast prodrug to parent drug conversion and led to high brain drug levels. Nevertheless, the choice of which strategy to use will always depend on the characteristics of the drug and must be a case-by-case approach.

1 May 2012 in Molecular Cancer Therapeutics
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GLGuénaëlle Levallet
Guénaëlle Levallet
EBEmmanuel Bergot
Emmanuel Bergot
MAMartine Antoine
Martine Antoine
CCChristian Creveuil
Christian Creveuil
ASAdriana Oliveira Santos
Adriana Oliveira Santos
I(Intergroupe Francophone De Cancérologie Thoracique (Ifct)
Intergroupe Francophone De Cancérologie Thoracique (Ifct)
We assessed the prognostic and predictive value of β-tubulin III (TUBB3) expression, as determined by immunohistochemistry, in 412 non–small cell lung cancer (NSCLC) specimens from early-stage patients who received neoadjuvant chemotherapy (paclitaxel- or gemcitabine-based) in a phase III trial (IFCT-0002). We also correlated TUBB3 expression with K-Ras and EGF receptor (EGFR) mutations in a subset of 208 cryopreserved specimens. High TUBB3 protein expression was associated with nonsquamous cell carcinomas (P < 0.001) and K-Ras mutation (P < 0.001). The 127 (30.8%) TUBB3-negative patients derived more than 1 year of overall survival advantage, with more than 84 months median overall survival versus 71.7 months for TUBB3-positive patients [HR, 1.58; 95% confidence interval (CI), 1.11–2.25)]. This prognostic value was confirmed in multivariate analysis (adjusted HR for death, 1.51; 95% CI, 1.04–2.21; P = 0.031) with a bootstrapping validation procedure. TUBB3 expression was associated with nonresponse to chemotherapy (adjusted HR, 1.31; 95% CI, 1.01–1.70; P = 0.044) but had no predictive value (taxane vs. gemcitabine). Taking account of these clinical findings, we further investigated TUBB3 expression in isogenic human bronchial cell lines only differing by K-Ras gene status and assessed the effect of K-Ras short interfering RNA (siRNA) mediated depletion, cell hypoxia, or pharmacologic inhibitors of K-Ras downstream effectors, on TUBB3 protein cell content. siRNA K-Ras knockdown, inhibition of RAF/MEK (MAP–ERK kinase) and phosphoinositide 3-kinase (PI3K)/AKT signaling, and hypoxia were shown to downregulate TUBB3 expression in bronchial cells. This study is the first one to identify K-Ras mutations as determinant of TUBB3 expression, a chemoresistance marker. Our in vitro data deserve studies combining standard chemotherapy with anti-MEK or anti-PI3K drugs in patients with TUBB3-overexpressing tumors. Mol Cancer Ther; 11(5); 1203–13. ©2012 AACR.

5 November 2018 in Nutrients
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Ana Carolina Almeida GonçalvesAna Carolina Almeida Gonçalves
Ana Carolina Almeida Gonçalves
Márcio José de Abreu Marques RodriguesMárcio José de Abreu Marques Rodrigues
Márcio José de Abreu Marques Rodrigues
ASAdriana Oliveira Santos
Adriana Oliveira Santos
Gilberto AlvesGilberto Alves
Gilberto Alves
Luís R. SilvaLuís R. Silva
Luís R. Silva
This study aimed to compare three different extracts of Saco sweet cherry, namely the non-colored fraction, colored fraction, and total extract concerning phenolic composition, antioxidant and antidiabetic potential, and erythrocytes’ protection and effects on Caco-2 cells. Twenty-two phenolic compounds were identified using high-performance liquid chromatography with diode-array detection. Hydroxycinnamic acids were the most predominant in both the non-colored fraction and total extract, while cyanidin-3-O-rutinoside was the main anthocyanin found in the colored fraction. The total extract was the most effective against 1,1-diphenyl-2-picrylhydrazyl, nitric oxide, and superoxide radicals, and in the inhibition of α-glucosidase enzyme. The colored fraction revealed the best activity against hemoglobin oxidation and hemolysis. Regarding to Caco-2 cells, the colored extract exhibited the highest cytotoxic effects, while the total extract was the most efficient in protecting these cells against oxidative damage induced by tert-butyl hydroperoxide.

18 July 2022 in Pharmaceutics
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SMSara Meirinho
Sara Meirinho
Márcio José de Abreu Marques RodriguesMárcio José de Abreu Marques Rodrigues
Márcio José de Abreu Marques Rodrigues
ASAdriana Oliveira Santos
Adriana Oliveira Santos
AFAmílcar Falcão
Amílcar Falcão
Gilberto AlvesGilberto Alves
Gilberto Alves
Efforts in discovering new and effective neurotherapeutics are made daily, although most fail to reach clinical trials. The main reason is their poor bioavailability, related to poor aqueous solubility, limited permeability through biological membranes, and the hepatic first-pass metabolism. Nevertheless, crossing the blood–brain barrier is the major drawback associated with brain drug delivery. To overcome it, intranasal administration has become more attractive, in some cases even surpassing the oral route. The unique anatomical features of the nasal cavity allow partial direct drug delivery to the brain, circumventing the blood–brain barrier. Systemic absorption through the nasal cavity also avoids the hepatic first-pass metabolism, increasing the systemic bioavailability of highly metabolized entities. Nevertheless, most neurotherapeutics present physicochemical characteristics that require them to be formulated in lipidic nanosystems as self-emulsifying drug delivery systems (SEDDS). These are isotropic mixtures of oils, surfactants, and co-surfactants that, after aqueous dilution, generate micro or nanoemulsions loading high concentrations of lipophilic drugs. SEDDS should overcome drug precipitation in absorption sites, increase their permeation through absorptive membranes, and enhance the stability of labile drugs against enzymatic activity. Thus, combining the advantages of SEDDS and those of the intranasal route for brain delivery, an increase in drugs’ brain targeting and bioavailability could be expected. This review deeply characterizes SEDDS as a lipidic nanosystem, gathering important information regarding the mechanisms associated with the intranasal delivery of drugs loaded in SEDDS. In the end, in vivo results after SEDDS intranasal or oral administration are discussed, globally revealing their efficacy in comparison with common solutions or suspensions.

1 September 2006 in Reviews on Recent Clinical Trials
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João Nuno MoreiraJoão Nuno Moreira
João Nuno Moreira
ASAdriana Oliveira Santos
Adriana Oliveira Santos
SSSergio Simoes
Sergio Simoes
The identification of activated oncogenes, such as the bcl-2, in several types of cancer has made it possible to consider such genes as targets for antitumor therapy. Bcl-2 is an anti-apoptotic protein, whose overexpression is associated with chemotherapy resistant cancer, aggressive clinical course and poor survival. The development of novel targeted gene-silencing strategies, such as those based on the use of antisense oligonucleotides, represents a renewed hope in the treatment of cancer. Within this scope, this review covers the main pre-clinical aspects and the most recent clinical data obtained with Oblimersen sodium (Genta Inc.). Oblimersen is a 18-mer phosphorothioate antisense oligonucleotide designed to bind to the first six codons of the human bcl-2 mRNA. Phase I/II trials indicate that infusion of Oblimersen provides biologically relevant plasma levels that lead to downregulation of target Bcl-2 protein. Moreover, the use of Oblimersen in combination with chemotherapy in a variety of cancers has shown promising response rates with good tolerability. Randomized phase III trials are currently underway to evaluate whether the combined use of Oblimersen with standard treatment is superior to standard treatment alone in chronic lymphocytic leukaemia, malignant melanoma and multiple myeloma. Overall, the enhanced efficacy of anticancer treatments of this bcl-2-targeted antisense therapy represents a promising new apoptosis-modulating strategy.