Combinatory approach for developing silk fibroin-based scaffolds seeded with human adipose-derived stem cells for a cartilage tissue engineering applications

Several processing technologies have been combined to create scaffolds for different tissue engineering (TE) applications. Hydrogels have been extensively used for cartilage TE applications, presenting several structural similarities to the natural extracellular matrix of cartilage tissue environment[1]. From the different biodegradable materials proposed as matrices for cartilage scaffolding[2], silk fibroin (SF) presents high versatility, processability and tailored mechanical properties, which make this protein attractive for the development of innovative matrices for cartilage TE purposes[3]. In a previous study, we proposed fast formed SF hydrogels produced through a horseradish peroxidase (HRP) and hydrogen peroxide (H2O2) crosslinking reaction, taking advantage of the presence of tyrosine groups[4]. In this work, macro-/micro-porous SF scaffolds derived from enzymatically cross- linked SF hydrogels by a HRP/H2O2 complex were produced in combination with salt-leaching and freeze-drying methodologies. The scaffolds morphology, mechanical properties and chemical characterization were assessed by mean of different characterization techniques (SEM, micro-CT, Instron, FTIR and XRD). The scaffolds structural integrity was evaluated by swelling ratio and degradation profile studies. The in vitro ability to support the adhesion, proliferation and differentiation into the chondrogenic lineage was tested using human adipose-derived stem cells (hASCs) cultured over 28 days in basal and chondrogenic conditions. Cell behaviour in the presence of the SF scaffolds was evaluated through different quantitative (GAGs/DNA and RT-PCR) and qualitative (live/dead, SEM, histology and immunocytochemistry) assays. The in vivo biocompatibility of the SF-based scaffolds was also assessed by subcutaneous implantation in mice for 2 and 4 weeks and analysed by means of hematoxylin & eosin (H&E) staining and immunohistochemical analysis of CD31 angiogenic marker. The results showed highly porous and interconnected SF structures that allowed cell adhesion and infiltration into the scaffolds. In vitro cell viability and proliferation were also observed over the 28 days of culturing in basal conditions and a significant increase of GAGs content was detected on constructs cultured in chondrogenic differentiation medium. In vivo results showed that the implanted scaffolds allowed tissue ingrowthâ s and blood vessels formation/infiltration. The obtained results demonstrated that the innovative approach of combining enzymatically cross-linked SF hydrogels with the salt- leaching and freeze-drying methodologies allowed to produce more versatile scaffold architectures with appropriate mechanical properties and large swelling ability. The positive influence over in vitro chondrogenic differentiation and in vivo response, revealed by the new tissue formation and angiogenesis within the porous scaffolds, validates the proposed macro-/micro-porous SF scaffolds for being used in cartilage TE applications. Moreover, the versatility of these combinatory approach can allow for further applications in other musculoskeletal TE strategies.Investigator FCT program IF/00423/2012 and IF/00411/2013 are also greatly acknowledged. Financial support from FCT/MCTES (Fundação para a Ciência e a Tecnologia/ Ministério da Ciência, Tecnologia, e Ensino Superior) and Fundo Social Europeu através do Programa Operacional do Capital Humano (FSE/POCH), PD/59/2013, PD/BD/113806/2015.info:eu-repo/semantics/publishedVersio

Expression of receptor activator of NFkB (RANK) drives stemness and resistance to therapy in ER+HER2- breast cancer

© Gomes et al. Copyright: Gomes et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License 3.0 (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.The role of RANKL-RANK pathway in progesterone-driven mammary carcinogenesis and triple negative breast cancer tumorigenesis has been well characterized. However, and despite evidences of the existence of RANK-positive hormone receptor (HR)-positive breast tumors, the implication of RANK expression in HR-positive breast cancers has not been addressed before. Here, we report that RANK pathway affects the expression of cell cycle regulators and decreases sensitivity to fulvestrant of estrogen receptor (ER)-positive (ER+)/HER2- breast cancer cells, MCF-7 and T47D. Moreover, RANK overexpressing cells had a staminal and mesenchymal phenotype, with decreased proliferation rate and decreased susceptibility to chemotherapy, but were more invasive in vivo. In silico analysis of the transcriptome of human breast tumors, confirmed the association between RANK expression and stem cell and mesenchymal markers in ER+HER2- tumors. Importantly, exposure of ER+HER2- cells to continuous RANK pathway activation by exogenous RANKL, in vitro and in vivo, induced a negative feedback effect, independent of RANK levels, leading to the downregulation of HR and increased resistance to hormone therapy. These results suggest that ER+HER2- RANK-positive cells may constitute an important reservoir of slow cycling, therapy-resistance cancer cells; and that RANK pathway activation is deleterious in all ER+HER2- breast cancer cells, independently of RANK levels.This project was funded by the research project PTDC/MED-ONC/28636/2017 from Fundação para a Ciência e a Tecnologia (FCT)/Ministério da Ciência, Tecnologia e Ensino Superior (MCTES) through Fundos do Orçamento de Estado. IG is supported by the FCT PhD grant SFRH/BD/139178/2018info:eu-repo/semantics/publishedVersio

Study about eating habits of higher education students

Introduction: The transition from secondary school to university is associated with many changes, at the social and surrounding influences’ levels, which may be a risk factor for unhealthy lifestyles. It is known that the years spent at the university may be associated with poor eating habits, with levels of fast-food consumption higher than desirable, possibly low intake of fruits and vegetables and breakfast skipping, among others. Objective: This study investigated some eating habits in a sample of students frequenting higher education establishments in the Centre of Portugal. Methods: It was carried out a questionnaire survey of self-response to investigate some of the eating habits of the participants. The questionnaire was applied after all ethical issues were guaranteed and after approval by the ethical committee. The number of valid questionnaires obtained was 670. Results: In the sample evaluated, most of the students revealed satisfactory eating habits, with significant differences between age groups, the area of studies and the practice of high competition sport. A considerable percentage of the participants, 40.8%, ate 5 meals per day and only 0.6% ate less than 3 meals per day. Only 6.6% of the participants indicated that usually do not eat breakfast. In general, the participants’ breakfast included milk (54.0% of positive answers), bread (45.8% of positive answers), cereals (32.7% of positive answers) and coffee (23.9% of positive answers). Regarding lunch, 30.1% of the participants ate soup, 28.4% consumed vegetables, 28.2% ate pasta, 21.6% fish, 16.0% potatoes, 2.5% yoghurt, 15.5% soft juices, 4.3% juices, 23.6% salad, 10.4% chips, 58.2% meat, 38.5% rice, 27.8% fruit, 9.4% a sweet desert and 44.9% drank water. Conclusions: The results pointed to the necessity of improving educational programs which can contribute to improve university students’ eating habits.info:eu-repo/semantics/publishedVersio

Genome-wide diversity and differentiation in New World populations of the human malaria parasite Plasmodium vivax.

BACKGROUND: The Americas were the last continent colonized by humans carrying malaria parasites. Plasmodium falciparum from the New World shows very little genetic diversity and greater linkage disequilibrium, compared with its African counterparts, and is clearly subdivided into local, highly divergent populations. However, limited available data have revealed extensive genetic diversity in American populations of another major human malaria parasite, P. vivax. METHODS: We used an improved sample preparation strategy and next-generation sequencing to characterize 9 high-quality P. vivax genome sequences from northwestern Brazil. These new data were compared with publicly available sequences from recently sampled clinical P. vivax isolates from Brazil (BRA, total n = 11 sequences), Peru (PER, n = 23), Colombia (COL, n = 31), and Mexico (MEX, n = 19). PRINCIPAL FINDINGS/CONCLUSIONS: We found that New World populations of P. vivax are as diverse (nucleotide diversity π between 5.2 × 10-4 and 6.2 × 10-4) as P. vivax populations from Southeast Asia, where malaria transmission is substantially more intense. They display several non-synonymous nucleotide substitutions (some of them previously undescribed) in genes known or suspected to be involved in antimalarial drug resistance, such as dhfr, dhps, mdr1, mrp1, and mrp-2, but not in the chloroquine resistance transporter ortholog (crt-o) gene. Moreover, P. vivax in the Americas is much less geographically substructured than local P. falciparum populations, with relatively little between-population genome-wide differentiation (pairwise FST values ranging between 0.025 and 0.092). Finally, P. vivax populations show a rapid decline in linkage disequilibrium with increasing distance between pairs of polymorphic sites, consistent with very frequent outcrossing. We hypothesize that the high diversity of present-day P. vivax lineages in the Americas originated from successive migratory waves and subsequent admixture between parasite lineages from geographically diverse sites. Further genome-wide analyses are required to test the demographic scenario suggested by our data

East Asia Today

East Asia attracts growing interest in the West. Th e region is the world’s hotbed of economic growth, led by burgeoning China aided by more advanced Asian economies investing heavily in manufacturing and trading networks involving China. Western entrepreneurs clamor to join the China wave

An shRNA-Based Screen of Splicing Regulators Identifies SFRS3 as a Negative Regulator of IL-1β Secretion

The generation of diversity and plasticity of transcriptional programs are key components of effective vertebrate immune responses. The role of Alternative Splicing has been recognized, but it is underappreciated and poorly understood as a critical mechanism for the regulation and fine-tuning of physiological immune responses. Here we report the generation of loss-of-function phenotypes for a large collection of genes known or predicted to be involved in the splicing reaction and the identification of 19 novel regulators of IL-1β secretion in response to E. coli challenge of THP-1 cells. Twelve of these genes are required for IL-1β secretion, while seven are negative regulators of this process. Silencing of SFRS3 increased IL-1β secretion due to elevation of IL-1β and caspase-1 mRNA in addition to active caspase-1 levels. This study points to the relevance of splicing in the regulation of auto-inflammatory diseases

A complex scenario of tuberculosis transmission is revealed through genetic and epidemiological surveys in Porto

Tuberculosis (TB) incidence is decreasing worldwide and eradication is becoming plausible. In low-incidence countries, intervention on migrant populations is considered one of the most important strategies for elimination. However, such measures are inappropriate in European areas where TB is largely endemic, such as Porto in Portugal. We aim to understand transmission chains in Porto through a genetic characterization of Mycobacterium tuberculosis strains and through a detailed epidemiological evaluation of cases.This work was developed under the scope of the project NORTE-01-0145-FEDER-000013, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER), and supported by contributions from Iceland, Liechtenstein and Norway through the European Economic Area Grants under the Public Health Initiative programme, (PT06, Project 000138DT1). TR is supported by the Portuguese Foundation for Science and Technology (FCT) through a post-doctoral grant (SFRH/BPD/108126/2015)info:eu-repo/semantics/publishedVersio

Spatial and Temporal Variations in the Annual Pollen Index Recorded by Sites Belonging to the Portuguese Aerobiology Network

This study presents the findings of a 10-year survey carried out by the Portuguese Aerobiology Network (RPA) at seven pollen-monitoring stations: five mainland stations (Oporto, Coimbra, Lisbon, Évora and Portimão) and two insular stations [Funchal (Madeira archipelago) and Ponta Delgada (Azores archipelago)]. The main aim of the study was to examine spatial and temporal variations in the Annual Pollen Index (API) with particular focus on the most frequently recorded pollen types. Pollen monitoring (2003–2012) was carried out using Hirst-type volumetric spore traps, following the minimum recommendations proposed by the European Aerobiology Society Working Group on Quality Control. Daily pollen data were examined for similarities using the Kruskal–Wallis nonparametric test and multivariate regression trees. Simple linear regression analysis was used to describe trends in API. The airborne pollen spectrum at RPA stations is dominated by important allergenic pollen types such as Poaceae, Olea and Urticaceae. Statistically significant differences were witnessed in the API recorded at the seven stations. Mean API is higher in the southern mainland cities, e.g. Évora, Lisbon and Portimão, and lower in insular and littoral cities. There were also a number of significant trends in API during the 10-year study. This report identifies spatial and temporal variations in the amount of airborne pollen recorded annually in the Portuguese territory. There were also a number of significant changes in API, but no general increases in the amount of airborne pollen