The involvement of CDH1 in cancer angiogenesis

Dissertação para obtenção do Grau de Mestre em BiotecnologiaCancer is one of the leading causes of death worldwide. Biological hallmarks such as induced and sustained angiogenesis are implicated in tumour progression, as well as invasion and metastasis which are the major causes of cancer-related mortality. E-Cadherin impairment on the cell membrane is intimately related with invasion and metastasis. Also, increased levels of vascular endothelial growth factor (VEGF), an angiogenic marker, and its receptor on the plasma membrane can be implicated in tumour progression. This work was focused on how the inactivation of E-Cadherin, a molecule associated to an invasive phenotype can be related with angiogenesis, probably through VEGF-A expression. Two different cell lines without expression of E-Cadherin and stably transduced to express wild-type (WT) E-Cadherin were used to carry out this study: AGS Par/WT (from stomach) and MDA-435 Mock/WT (from breast). Immunohistochemical staining was performed to determine the cellular localization and western blot analysis was performed to assess the expression levels of E-Cadherin. VEGFA mRNA levels were assessed by quantitative Real-time PCR. Additionally, we determined the levels phosphorylated (phospho) ERK1/2, as well as the expression levels of total ERK1/2. To study the angiogenic role of E-cadherin the chick embryo Chorioallantoic Membrane (CAM) assay was used. We characterise in vivo the different cell lines concerning both angiogenic and tumorigenic responses dependent on E-Cadherin. Only cell lines stably expressing WT human E-Cadherin showed levels of expression of this protein at the cell membrane regardless of their tissue of origin. In vitro, AGS and MDA-435 cells expressing WT E-Cadherin revealed an increased expression of VEGFA in comparison to the control although not statically significant. In addition, both phospho-ERK1/2 and total ERK1/2 presented similar levels of expression regardless of the tissue of origin and E-Cadherin expression. Both angiogenic and tumorigenic responses in AGS WT was significantly increased in comparison to the control. The MDA-435 WT cells revealed increased tumorigenic response in comparison to the control. Overall, these results suggest that E-Cadherin expression is important for micro-tumour formation as well as for neovascularisation but this effect is dependent on the in vivo context

Population Structure and Reproduction of Pseudione elongata africana (Bopyridae, Isopoda)

The population structure and reproductive fitness of Pseudione elongata africana parasitizing the shrimp Palaemon concinnus were studied in two mangroves in Mozambique. About 100 host specimens were sampled every 15 days for 12 months at Costa do Sol, a peri-urban mangrove near Maputo, and at Saco, a near pristine mangrove at Inhaca Island. Parasites were removed from the branchiostegites of the shrimp and measured. Ovigerous females were selected and the eggs and embryos removed from the brood pouch and counted after staging their level of development. At Costa do Sol, the total length of female parasites (FPTL) was about 17% higher than at Saco. Ovigerous females were also more abundant at Costa do Sol in both the dry and wet seasons. The average brood size ranged from 89 to 207 eggs mm-1 FPTL in the Saco and 177 to 357 eggs mm-1 at Costa do Sol. These data provide baseline information on the population structure and reproduction of this parasite in east African mangroves. Comparative data on these parameters in peri-urban and more isolated mangroves may also lay the groundwork for the use of parasite reproduction as an indicator of anthropogenic pressure

Integrated biomimetic carbon nanotube composites for in vivo systems

CESAMAs interest in using carbon nanotubes for developing biologically compatible systems continues to grow, biological inspiration is stimulating new directions for in vivo approaches. The ability to integrate nanotechnology-based systems in the body will provide greater successes if the implanted material is made to mimic elements of the biological milieu especially through tuning physical and chemical characteristics. Here, we demonstrate the highly successful capacity for in vivo implantation of a new carbon nanotube-based composite that is, itself, integrated with a hydroxyapatite-polymethyl methacrylate to create a nanocomposite. The success of this approach is grounded in finely tailoring the physical and chemical properties of this composite for the critical demands of biological integration. This is accomplished through controlling the surface modification scheme, which affects the interactions between carbon nanotubes and the hydroxyapatite-polymethyl methacrylate. Furthermore, we carefully examine cellular response with respect to adhesion and proliferation to examine in vitro compatibility capacity. Our results indicate that this new composite accelerates cell maturation through providing a mechanically competent bone matrix; this likely facilitates osteointegration in vivo. We believe that these results will have applications in a diversity of areas including carbon nanotube, regeneration, chemistry, and engineering research.NANO/NMed-AT/0115/2007SFRH/BPD/14677/2003FC

TRATAMENTO ENDOVASCULAR DE SÍNDROME DA VEIA CAVA SUPERIOR POR DISPOSITIVO DE ACESSO VENOSO CENTRAL TOTALMENTE IMPLANTÁVEL — CASO CLÍNICO

Introdução: O síndrome da Veia Cava Superior (sVCS) benigno é raro e pode estar relacionado com um dispositivo de acesso venoso central totalmente implantável (DAVCTI). Nos últimos 20 anos, a dilatação com colocação de stent por via percutânea endovascular tem surgido como uma opção viável para a terapêutica do sVCS. Caso clínico: Apresentamos o caso de uma mulher de 42 anos com o diagnóstico de linfoma de Hodgkin clássico que desenvolveu sVCS um ano após a colocação de DAVCTI e em que, após falência da terapêutica conservadora, se colocou uma endoprótese auto-expansível pelo DAVCTI com bom resultado imagiológico e clínico. Conclusão: O tratamento endovascular do sVCS usando o lúmen do DAVCTI é seguro e pode ser considerada terapêutica de primeira linha

MAMMALS IN PORTUGAL : A data set of terrestrial, volant, and marine mammal occurrences in P ortugal

Mammals are threatened worldwide, with 26% of all species being includedin the IUCN threatened categories. This overall pattern is primarily associatedwith habitat loss or degradation, and human persecution for terrestrial mam-mals, and pollution, open net fishing, climate change, and prey depletion formarine mammals. Mammals play a key role in maintaining ecosystems func-tionality and resilience, and therefore information on their distribution is cru-cial to delineate and support conservation actions. MAMMALS INPORTUGAL is a publicly available data set compiling unpublishedgeoreferenced occurrence records of 92 terrestrial, volant, and marine mam-mals in mainland Portugal and archipelagos of the Azores and Madeira thatincludes 105,026 data entries between 1873 and 2021 (72% of the data occur-ring in 2000 and 2021). The methods used to collect the data were: live obser-vations/captures (43%), sign surveys (35%), camera trapping (16%),bioacoustics surveys (4%) and radiotracking, and inquiries that represent lessthan 1% of the records. The data set includes 13 types of records: (1) burrowsjsoil moundsjtunnel, (2) capture, (3) colony, (4) dead animaljhairjskullsjjaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8),observation in shelters, (9) photo trappingjvideo, (10) predators dietjpelletsjpine cones/nuts, (11) scatjtrackjditch, (12) telemetry and (13) vocalizationjecholocation. The spatial uncertainty of most records ranges between 0 and100 m (76%). Rodentia (n=31,573) has the highest number of records followedby Chiroptera (n=18,857), Carnivora (n=18,594), Lagomorpha (n=17,496),Cetartiodactyla (n=11,568) and Eulipotyphla (n=7008). The data setincludes records of species classified by the IUCN as threatened(e.g.,Oryctolagus cuniculus[n=12,159],Monachus monachus[n=1,512],andLynx pardinus[n=197]). We believe that this data set may stimulate thepublication of other European countries data sets that would certainly contrib-ute to ecology and conservation-related research, and therefore assisting onthe development of more accurate and tailored conservation managementstrategies for each species. There are no copyright restrictions; please cite thisdata paper when the data are used in publications.info:eu-repo/semantics/publishedVersio

Mammals in Portugal: a data set of terrestrial, volant, and marine mammal occurrences in Portugal

Mammals are threatened worldwide, with ~26% of all species being included in the IUCN threatened categories. This overall pattern is primarily associated with habitat loss or degradation, and human persecution for terrestrial mammals, and pollution, open net fishing, climate change, and prey depletion for marine mammals. Mammals play a key role in maintaining ecosystems functionality and resilience, and therefore information on their distribution is crucial to delineate and support conservation actions. MAMMALS IN PORTUGAL is a publicly available data set compiling unpublished georeferenced occurrence records of 92 terrestrial, volant, and marine mammals in mainland Portugal and archipelagos of the Azores and Madeira that includes 105,026 data entries between 1873 and 2021 (72% of the data occurring in 2000 and 2021). The methods used to collect the data were: live observations/captures (43%), sign surveys (35%), camera trapping (16%), bioacoustics surveys (4%) and radiotracking, and inquiries that represent less than 1% of the records. The data set includes 13 types of records: (1) burrows | soil mounds | tunnel, (2) capture, (3) colony, (4) dead animal | hair | skulls | jaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8), observation in shelters, (9) photo trapping | video, (10) predators diet | pellets | pine cones/nuts, (11) scat | track | ditch, (12) telemetry and (13) vocalization | echolocation. The spatial uncertainty of most records ranges between 0 and 100 m (76%). Rodentia (n =31,573) has the highest number of records followed by Chiroptera (n = 18,857), Carnivora (n = 18,594), Lagomorpha (n = 17,496), Cetartiodactyla (n = 11,568) and Eulipotyphla (n = 7008). The data set includes records of species classified by the IUCN as threatened (e.g., Oryctolagus cuniculus [n = 12,159], Monachus monachus [n = 1,512], and Lynx pardinus [n = 197]). We believe that this data set may stimulate the publication of other European countries data sets that would certainly contribute to ecology and conservation-related research, and therefore assisting on the development of more accurate and tailored conservation management strategies for each species. There are no copyright restrictions; please cite this data paper when the data are used in publications

Low doses of ionizing radiation induce angiogenesis : therapeutic implications

Angiogenesis is the de novo formation of blood vessels from pre-existing ones, and is a process regulated by a fine-tuned balance between molecules that either stimulate or inhibit vessel growth. When this balance is disrupted, vessel formation or regression occurs in an exacerbated manner, which can lead to angiogenesisdependent diseases, such as cancer and ischemia. We have previously demonstrated that doses of ionizing radiation lower than 0.8 Gy, defined here as low doses of ionizing radiation (LDIR), induce angiogenesis by activating endothelial cells. In physiological contexts, LDIR promote angiogenesis during zebrafish development and adult fin regeneration. Using experimental models, LDIR stimulated neovascularization after ischemia induction and promoted tumor growth and metastasis formation by enhancing angiogenesis. These LDIR effects are relevant since they are present during radiotherapy in the peritumoral tissues and for that reason, the main aim of this doctoral thesis was to determine if LDIR induce angiogenesis in human tissues. Material from parietal peritoneum, located in peritumoral tissues, was removed from patients diagnosed with locally advanced rectal cancer who underwent neoadjuvant radiotherapy. According to our data, LDIR activate endothelial cells in peritumoral tissues, which is associated with increased microvascular density. This effect should be considered in the treatment plan report for patient follow-up and in future studies to establish a correlation between these doses and tumor dissemination. Additionally, this work focused on the mechanisms through which LDIR induce angiogenesis. Since adipocytes secrete multiple angiogenic factors and adipokines that induce angiogenesis, the effect of LDIR in modulating the pro-angiogenic potential of adipocytes was investigated. An in vitro model of adipocyte differentiation was used, and our data show that LDIR enhance the angiogenic potential of adipocyte-conditioned medium in vitro and in vivo. Lastly, this work reveals that even though regeneration is often regarded as a recapitulation of post-embryonic development, LDIR accelerate post-embryonic development but not regeneration, suggesting that the physiological context could be a major determinant of the specific phenotype promoted by LDIR

Automated high-throughput screening of carbon nanotube-based bio-nanocomposites for bone cement applications

In this work we demonstrate the potential of using an automated cell viability analyzer for developing high-throughput screening of orthopedic bioactive materials. We used a biomaterial of carbon nanotubes (CNTs)-based composite integrated with hydroxyapatite/ polymethyl methacrylate (HA/PMMA) with controlled physical and chemical properties to evaluate the usefulness of morphometric analysis in conjunction with trypan blue dye exclusion assays in MG63 cell cultures. The MG63 cell line, derived from human bone osteo - sarcoma, is often used as a model for studying osteoblast-like cellular response to bioactive materials for orthopedic surgery. The viability analyzer, Vi-CELLTM XR, Beckman Coulter, was used with trypan blue dye exclusion method in cell suspensions obtained after trypsinization along with determining the distribution plots of cell diameter and circularity, which are critical cellular characteristics. In addition, the activity of alkaline phosphatase (ALP), a typical representation of osteogenic activity of osteoblasts, was also measured spectrophotometrically using p-nitrophenol phosphate as the substrate. Comparative analysis of the frequency histogram of average cell diameter and circularity allowed for the analyses of significant alterations in cell morphology not only over time in control cultures (spherical vs. a flat morphology) but also with respect to PMMA and HA nanocomposites. After cell exposure to HA/PMMA/CNTs, a shift toward loss of cell circularity was observed. The appearances of more differentiated morphologic features were well correlated with the increase of secreted ALP activity. In conclusion, the evaluation of material-induced changes of cell morphology could represent a valuable prescreening test for bioactive properties.International Iberian Laboratory of Nanotechnology - NANO/NMed- AT/0115/2007FCT - Program Compromise with Science (to M.K.S. and P.M.)SFRH/BPD/14677/2003 (to V.S.S.

An In Vitro Evaluation of the Potential Neuroprotective Effects of Intranasal Lipid Nanoparticles Containing Astaxanthin Obtained from Different Sources: Comparative Studies

The intranasal route has been suggested as a promising alternative to improve the direct transport of molecules to the brain, avoiding the need to cross the blood–brain barrier (BBB). In this area, the use of lipid nanoparticles, namely solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC), has been highlighted as a promising strategy to improve the treatment of neurodegenerative diseases. In this work, formulations containing SLN and NLC that were loaded with astaxanthin that was obtained from different sources (astaxanthin extract (AE) from the algae Haematococcus pluvialis and pure astaxanthin (PA) from the fungi Blakeslea trispora) were prepared for nose-to-brain administration, and comparative in vitro experiments were performed to evaluate the biocompatibility of the formulations with nasal (RPMI 2650) and neuronal (SH-SY5Y) cells. Afterwards, the antioxidant activity of the formulations was evaluated for its potential neuroprotective effects, using different chemical aggressors. Finally, the cellular uptake of the astaxanthin was evaluated for the formulations that showed the greatest neuroprotection of the neuronal cells against chemical-induced damage. On the production day, all the formulations showed a particle size, a high encapsulation efficiency (EE), the presence of nanoparticles with a typical spherical shape, and a polydispersity index (PDI) and zeta potential (ZP) that are suitable for nose-to-brain administration. After three months of storage at room temperature, no significant changes were observed in the characterization parameters, predicting a good long-term stability. Furthermore, these formulations were shown to be safe with concentrations of up to 100 µg/mL in differentiated SH-SY5Y and RPMI 2650 cells. Regarding neuroprotection studies, the PA-loaded SLN and NLC formulations showed an ability to counteract some mechanisms of neurodegeneration, including oxidative stress. Moreover, when compared with the PA-loaded SLN, the PA-loaded NLC showed greater neuroprotective effects against the cytotoxicity induced by aggressors. In contrast, the AE-loaded SLN and NLC formulations showed no significant neuroprotective effects. Although further studies are needed to confirm these neuroprotective effects, the results of this study suggest that the intranasal administration of PA-loaded NLC may be a promising alternative to improve the treatment of neurodegenerative diseases