Monteiro L.S.,Instituto Superior Of Ciencias Da Saude Norte |
Antunes L.,Portuguese Institute of Oncology IPO Porto |
Bento M.J.,Portuguese Institute of Oncology IPO Porto |
Warnakulasuriya S.,Kings College London
Journal of Oral Pathology and Medicine | Year: 2013
Objectives: To analyse the trends and patterns of lip, oral and oro-pharyngeal cancer incidence in Portugal between 1998 and 2007. Patients and Methods: Data on lip, oral and oro-pharyngeal cancers was collected from the databases maintained at the three main Regional Cancer Registries of Portugal (1998-2007). The data were analysed by gender, age and by site. Incidence rates were age standardized by the direct method, and joinpoint regression was used to estimate trends in incidence. Results: During this 10-year period, a total of 9623 cases of lip, oral and oropharynx cancers were reported, 7565 (78.6%) in males and 2058 (21.4%) in females. There was an increase in the age-standardized incidence of oral cancers by 1.96% per year for both sexes grouped together and an increase of 4.34% per year for the female group. Oro-pharyngeal cancer showed an increase incidence trend of 3.49% per year for both sexes grouped together and an increase of 3.49% per year for male group among the sites analysed. Lip cancer showed a decrease in its incidence rate. Conclusion: In view of rising trends, it is necessary to implement policies on oral cancer control by initiating campaigns on oral cancer awareness and screening and to harness political measures on tobacco and alcohol control for the Portuguese population. © 2012 John Wiley & Sons A/S.
das Neves J.,University of Porto |
Amiji M.,Northeastern University |
Sarmento B.,University of Porto |
Sarmento B.,Instituto Superior Of Ciencias Da Saude Norte
Wiley Interdisciplinary Reviews: Nanomedicine and Nanobiotechnology | Year: 2011
Topical microbicides are a promising strategy in the prevention of vaginal and rectal HIV transmission as well as other sexually transmitted pathogens. The perspective of developing nanotechnology-based systems for topical microbicides seems to be useful because important features such as enhanced drug release, targeting, and epithelial penetration can be achieved. However, the interaction of nanoparticles with the mucus fluids that cover the cervicovaginal mucosal epithelium, which can work either as a docking point or as a barrier for diffusion, has been frequently neglected. In this review, we discuss the principles of nanosystems' adhesion to the mucosal tissue and how this relates to the development of optimized microbicide formulations. © 2011 John Wiley & Sons, Inc.
Fonte P.,Instituto Superior Of Ciencias Da Saude Norte
Biomatter | Year: 2012
PLGA nanoparticles are useful to protect and deliver proteins in a localized or targeted manner, with a long-term systemic delivery pattern intended to last for a period of time, depending on polymer bioerosion and biodegradability. However, the principal concern regarding these carriers is the hydrolytic instability of polymer in aqueous suspension. Freeze-drying is a commonly used method to stabilize nanoparticles, and cryoprotectants may be also used, to even increase its physical stability. The aim of the present work was to analyze the influence of cryoprotectants on nanoparticle stability and porosity after freeze-drying, which may influence protein release and stability. It was verified that freeze-drying significantly increased the number of pores on PLGA-NP surface, being more evident when cryoprotectants are added. The presence of pores is important in a lyophilizate to facilitate its reconstitution in water, although this may have consequences to protein release and stability. The release profile of insulin encapsulated into PLGA-NP showed an initial burst in the first 2 h and a sustained release up to 48 h. After nanoparticles freeze-drying the insulin release increased about 18% in the first 2 h due to the formation of pores, maintaining a sustained release during time. After freeze-drying with cryoprotectants, the amount of insulin released was higher for trehalose and lower for sucrose, glucose, fructose and sorbitol comparatively to freeze-dried PLGA-NP with no cryoprotectant added. Besides the porosity, the ability of cryoprotectants to be adsorbed on the nanoparticles surface may also play an important role on insulin release and stability.
Mendes R.A.,University of Porto |
Mendes R.A.,Instituto Superior Of Ciencias Da Saude Norte |
Carvalho J.F.,University of Porto |
Waal I.v.d.,VU University Amsterdam
Oral Oncology | Year: 2010
In the classification of Head and Neck Tumors, published in 2005 by the World Health Organization Classification, the odontogenic keratocyst has been reclassified as a benign intraosseous neoplasm, calling it "keratocystic odontogenic tumor" (KCOT). Significant differences on the molecular level between KCOT and other odontogenic cystic lesions suggest a different biological origin. Genetic and molecular research regarding odontogenic tumors, and KCOTs in particular, has led to an increasing amount of knowledge and understanding of their physiopathological pathways. A review of the biological behavior of this recognized aggressive pathological entity of the jaws and a contemporary outline of the molecular (growth factors, p53, PCNA and Ki-67, bcl-2) and genetic (PTCH, SHH) alterations associated with this odontogenic neoplasm provides a better understanding of the mechanisms involved in its development and strengthen the current concept that the KCOT should, indeed, be regarded as a neoplasm. Furthermore, markers known to be rapidly induced in response to growth factors, tumor promoters, cytokines, bacterial endotoxins, oncogenes, hormones and shear stress, such as COX-2, may also shed new light on the biological mechanisms involved in the development of these benign but sometimes aggressive neoplasms of the jaws. © 2009 Elsevier Ltd. All rights reserved.
Martins S.M.,University of Porto |
Martins S.M.,University of Southern Denmark |
Sarmento B.,University of Porto |
Sarmento B.,Instituto Superior Of Ciencias Da Saude Norte |
And 4 more authors.
European Journal of Pharmaceutics and Biopharmaceutics | Year: 2013
This study intended to investigate the ability of solid lipid nanoparticles (SLN) to deliver camptothecin into the brain parenchyma after crossing the blood-brain barrier. For that purpose, camptothecin-loaded SLN with mean size below 200 nm, low polydispersity index (<0.25), negative surface charge (-20 mV), and high camptothecin association efficiency (>94%) were produced. Synchrotron small and wide angle X-ray scattering (SAXS/WAXS) analysis indicates that SLN maintain their physical stability in contact with DMPC membrane, whereas SLN change the lamellar structure of DMPC into a cubic phase, which is associated with efficient release of the incorporated drugs. Cytotoxicity studies against glioma and macrophage human cell lines revealed that camptothecin-loaded SLN induced cell death with the lowest maximal inhibitory concentration (IC50) values, revealing higher antitumour activity of camptothecin-loaded SLN against gliomas. Furthermore, in vivo biodistribution studies of intravenous camptothecin-loaded SLN performed in rats proved the positive role of SLN on the brain targeting since significant higher brain accumulation of camptothecin was observed, compared to non-encapsulated drug. Pharmacokinetic studies further demonstrated lower deposition of camptothecin in peripheral organs, when encapsulated into SLN, with consequent decrease in potential side toxicological effects. These results confirmed the potential of camptothecin-loaded SLN for antitumour brain treatments.