The Doctor, the Smoking Patient and the Challenge of Electronic Cigarettes

Apesar dos esforços e das medidas de prevenção e controlo que vêm sendo adotadas desde a década de 80 do século passado, o tabagismo continua a ser, em Portugal e no mundo, um dos mais importantes fatores evitáveis de doença crónica e de mortalidade prematura. 1 A carga da doença atribuível ao tabaco em Portugal foi estimada por Borges et al 2 há mais de uma década. Nesse estudo 11,7% das mortes em Portugal foram atribuídas ao consumo de tabaco. Medida a carga da doença atra- vés dos anos de vida ajustados por incapacidade (disabi- lity adjusted life years — DALY) gerados pela mortalidade, a proporção da carga da doença atribuível ao tabaco foi de 11,2%. Baseados em dados disponíveis para Portugal, em 2005, os autores evidenciaram grande disparidade na análise de género, sendo o tabaco no homem responsável por 15,4% da carga da doença e 17,7% das mortes, e na mulher responsável por 4,9% da carga da doença e 5,2% das mortes. O estudo apresentava ainda estimativas sobre a carga da doença redutível, ou seja, a redução de mortali- dade e DALY que ocorreriam se os fumadores abandonas- sem o tabagismo e passassem a apresentar o risco médio das populações de ex-fumadores, caso em que a carga da doença se reduziria em 5,8% (7,8% dos homens e 2,8% das mulheres) e as mortes em 5,8% (8,5% dos homens e 2,9% das mulheres). Nos anos seguintes, muito foi feito em Portugal para melhorar o controlo do tabagismo. No entan- to, e apesar destes esforços, o consumo de tabaco é ainda crescente na mulher portuguesa 1 . Em 2007, a Direção-Geral de Saúde emitiu o Progra- ma-Tipo de Actuação em Cessação Tabágica 3 e em 2008, a Convenção-Quadro para o Controlo do Tabagismo da Organização Mundial de Saúde (OMS) propôs um conjunto de estratégias concertadas para ajudar os países a contro- lar a epidemia do tabaco e a reduzir o seu rasto mortífero. 4 O acrónimo MPOWER resume as seis políticas com mais impacto: M — Monitorizar a epidemia e as políticas de con- trolo; P — Proteger do fumo ambiental; O — Oferecer ajuda na cessação tabágica; W — (Warn) avisar sobre os male- fícios do tabaco; E — (Enforce bans) Impor a proibição da publicidade, promoção e patrocínio do tabaco; R — (Raise taxes) Aumentar os impostos sobre os produtos do taba- co. Estes pilares viriam a servir de referência para o Plano Nacional para a Prevenção e Controlo do Tabagismo (PNPCT) em Portugal, lançado em 2012. 5 Oferecer ajuda na cessação tabágica é uma das principais estratégias no controlo do tabagismo, mas as restantes medidas preconi- zadas pela OMS necessitam de implementação e desen- volvimento, para que o seu efeito sinérgico se faça sentir. Um enorme desafio surgiu, nos últimos anos, com o aparecimento de novos produtos de tabaco, entre os quais os cigarros electrónicos (CE), que podem colocar em cau- sa os esforços desenvolvidos nas últimas duas décadas. Em Portugal, este fenómeno é ainda menos expressivo do que o observado em muitos países, mas obriga o médico a estar bem informado sobre estes novos produtos e os seus riscos (já conhecidos ou potenciais). Apesar da população portuguesa ter aumentado a per- cepção de risco relacionado com estes produtos, 6 cerca de um terço da população europeia (29,1%) não sabe se são ou não prejudiciais. 6 Consequentemente, tem-se verificado um aumento crescente da sua experimentação e consumo diário, não só em Portugal 6 como na Europa em geral. 7 Habitualmente o médico não aborda o consumo de CE com o seu doente. Uma investigação recente 8 conclui que apenas uma minoria dos médicos o faz de acordo com as recomendações para a melhor prática da cessação tabági- ca. Um dos maiores problemas da ‘discussão sobre cigar- ros eletrónicos’ é o da ambivalência gerada pela incerteza e contradição da informação científica disponível.info:eu-repo/semantics/publishedVersio

Spherical and rod shaped mesoporous nanosilicas for cancer- targeted and photosensitizers delivery in photodynamic therapy

Mesoporous silica nanoparticles (MSNPs) have attracted much attention in many biomedical applications. One of the fields in which smart functional nanosystems have found wide application is cancer treatment. Here, we present new silica nanoparticle-based systems which have been explored as efficient vehicles to transport and deliver photosensitizers (PSs) into tumor tissues during photodynamic therapy (PDT). In this work, we report the preparation, characterization, and in vitro studies of distinct shaped MSNPs grafted with S-glycoside porphyrins (Pors). The ensuing nanomaterials were fully characterized, and their properties as third-generation PSs for PDT against two bladder cancer cell lines, HT-1376 and UM-UC-3, were examined. The best uptake results were obtained for MSNP-PS2, while MSNP-PS1 showed the lowest cellular uptake among the nanocarriers tested, but revealed the best phototoxicity in both cancer cells. Overall, the phototoxicity was higher with MSNPs than with mesoporous silica nanorods (MSNRs) and higher uptake and phototoxicity were consistently observed in UM-UC-3 rather than in HT-1376 cancer cellpublishe

Galactodendritic Phthalocyanine Targets Carbohydrate- Binding Proteins Enhancing Photodynamic Therapy

Photosensitizers (PSs) are of crucial importance in the effectiveness of photodynamic therapy (PDT) for cancer. Due to their high reactive oxygen species production and strong absorption in the wavelength range between 650 and 850 nm, where tissue light penetration is rather high, phthalocyanines (Pcs) have been studied as PSs of excellence. In this work, we report the evaluation of a phthalocyanine surrounded by a carbohydrate shell of sixteen galactose units distributed in a dendritic manner (PcGal16) as a new and efficient third generation PSs for PDT against two bladder cancer cell lines, HT-1376 and UMUC- 3. Here, we define the role of galacto-dendritic units in promoting the uptake of a Pc through interaction with GLUT1 and galectin-1. The photoactivation of PcGal16 induces cell death by generating oxidative stress. Although PDT with PcGal16 induces an increase on the activity of antioxidant enzymes immediately after PDT, bladder cancer cells are unable to recover from the PDT-induced damage effects for at least 72 h after treatment. PcGal16 co-localization with galectin-1 and GLUT1 and/or generation of oxidative stress after PcGal16 photoactivation induces changes in the levels of these proteins. Knockdown of galectin-1 and GLUT1, via small interfering RNA (siRNA), in bladder cancer cells decreases intracellular uptake and phototoxicity of PcGal16. The results reported herein show PcGal16 as a promising therapeutic agent for the treatment of bladder cancer, which is the fifth most common type of cancer with the highest rate of recurrence of any cancer

Antimicrobial Photodynamic Therapy: Study of Bacterial Recovery Viability and Potential Development of Resistance after Treatment

Antimicrobial photodynamic therapy (aPDT) has emerged in the clinical field as a potential alternative to antibiotics to treat microbial infections. No cases of microbial viability recovery or any resistance mechanisms against it are yet known. 5,10,15-tris(1-Methylpyridinium-4-yl)-20-(pentafluorophenyl)-porphyrin triiodide (Tri-Py+-Me-PF) was used as photosensitizer. Vibrio fischeri and recombinant Escherichia coli were the studied bacteria. To determine the bacterial recovery after treatment, Tri-Py+-Me-PF (5.0 μM) was added to bacterial suspensions and the samples were irradiated with white light (40 W m−2) for 270 minutes. Then, the samples were protected from light, aliquots collected at different intervals and the bioluminescence measured. To assess the development of resistance after treatment, bacterial suspensions were exposed to white light (25 minutes), in presence of 5.0 μM of Tri-Py+-Me-PF (99.99% of inactivation) and plated. After the first irradiation period, surviving colonies were collected from the plate and resuspended in PBS. Then, an identical protocol was used and repeated ten times for each bacterium. The results suggest that aPDT using Tri-Py+-Me-PF represents a promising approach to efficiently destroy bacteria since after a single treatment these microorganisms do not recover their viability and after ten generations of partially photosensitized cells neither of the bacteria develop resistance to the photodynamic process

Patterned Irradiation of YBa_2Cu_3O_(7-x) Thin Films

We present a new experiment on YBa_2Cu_3O_{7-x} (YBCO) thin films using spatially resolved heavy ion irradiation. Structures consisting of a periodic array of strong and weak pinning channels were created with the help of metal masks. The channels formed an angle of +/-45 Deg with respect to the symmetry axis of the photolithographically patterned structures. Investigations of the anisotropic transport properties of these structures were performed. We found striking resemblance to guided vortex motion as it was observed in YBCO single crystals containing an array of unidirected twin boundaries. The use of two additional test bridges allowed to determine in parallel the resistivities of the irradiated and unirradiated parts as well as the respective current-voltage characteristics. These measurements provided the input parameters for a numerical simulation of the potential distribution of the Hall patterning. In contrast to the unidirected twin boundaries in our experiment both strong and weak pinning regions are spatially extended. The interfaces between unirradiated and irradiated regions therefore form a Bose-glass contact. The experimentally observed magnetic field dependence of the transverse voltage vanishes faster than expected from the numerical simulation and we interpret this as a hydrodynamical interaction between a Bose-glass phase and a vortex liquid.Comment: 7 pages, 8 Eps figures included. Submitted to PR

Prototype of a nanostructured sensing contact lens for noninvasive intraocular pressure monitoring

To present the application of a new sensor based on a flexible, highly piezoresistive, nanocomposite, all-organic bilayer (BL) adapted to a contact lens (CL) for non-invasive monitoring intraocular pressure (IOP).Peer reviewe

The Pierre Auger Observatory III: Other Astrophysical Observations

Astrophysical observations of ultra-high-energy cosmic rays with the Pierre Auger ObservatoryComment: Contributions to the 32nd International Cosmic Ray Conference, Beijing, China, August 201

Measurement of the Depth of Maximum of Extensive Air Showers above 10^18 eV

We describe the measurement of the depth of maximum, Xmax, of the longitudinal development of air showers induced by cosmic rays. Almost four thousand events above 10^18 eV observed by the fluorescence detector of the Pierre Auger Observatory in coincidence with at least one surface detector station are selected for the analysis. The average shower maximum was found to evolve with energy at a rate of (106 +35/-21) g/cm^2/decade below 10^(18.24 +/- 0.05) eV and (24 +/- 3) g/cm^2/decade above this energy. The measured shower-to-shower fluctuations decrease from about 55 to 26 g/cm^2. The interpretation of these results in terms of the cosmic ray mass composition is briefly discussed.Comment: Accepted for publication by PR

A search for point sources of EeV photons

Measurements of air showers made using the hybrid technique developed with the fluorescence and surface detectors of the Pierre Auger Observatory allow a sensitive search for point sources of EeV photons anywhere in the exposed sky. A multivariate analysis reduces the background of hadronic cosmic rays. The search is sensitive to a declination band from -85{\deg} to +20{\deg}, in an energy range from 10^17.3 eV to 10^18.5 eV. No photon point source has been detected. An upper limit on the photon flux has been derived for every direction. The mean value of the energy flux limit that results from this, assuming a photon spectral index of -2, is 0.06 eV cm^-2 s^-1, and no celestial direction exceeds 0.25 eV cm^-2 s^-1. These upper limits constrain scenarios in which EeV cosmic ray protons are emitted by non-transient sources in the Galaxy.Comment: 28 pages, 10 figures, accepted for publication in The Astrophysical Journa

Reconstruction of inclined air showers detected with the Pierre Auger Observatory

We describe the method devised to reconstruct inclined cosmic-ray air showers with zenith angles greater than $60^\circ$ detected with the surface array of the Pierre Auger Observatory. The measured signals at the ground level are fitted to muon density distributions predicted with atmospheric cascade models to obtain the relative shower size as an overall normalization parameter. The method is evaluated using simulated showers to test its performance. The energy of the cosmic rays is calibrated using a sub-sample of events reconstructed with both the fluorescence and surface array techniques. The reconstruction method described here provides the basis of complementary analyses including an independent measurement of the energy spectrum of ultra-high energy cosmic rays using very inclined events collected by the Pierre Auger Observatory.Comment: 27 pages, 19 figures, accepted for publication in Journal of Cosmology and Astroparticle Physics (JCAP